tag:blogger.com,1999:blog-23749971657925288222024-03-14T06:25:24.426-07:00TexnoteBy Nikhil Bhosale and Bajirao JadhavUnknownnoreply@blogger.comBlogger86125tag:blogger.com,1999:blog-2374997165792528822.post-80150533274256751742017-03-24T05:08:00.000-07:002017-03-24T05:08:03.097-07:00Cutting<div dir="ltr" style="text-align: left;" trbidi="on">
<div>
<div>
<b>Cutting</b></div>
<div>
<b><br /></b></div>
<div>
The cutting of fully cut knitted goods covers the full spectrum of techniques available to producers of woven fabric garments, from hand shears to fully automatic systems.</div>
</div>
<div>
<br /></div>
<div>
<div>
Cutting systems can be categorised according to the cutting device used. The usual classification is:</div>
<div>
<br /></div>
<div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>hand shears;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>hand held power cutters;</div>
<div>
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>fixed location band knives;</div>
<div>
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span>die cutter systems;</div>
<div>
(5)<span class="Apple-tab-span" style="white-space: pre;"> </span>fully automatic cutter.</div>
<div>
<br /></div>
<div>
<i><b>Hand shears</b></i></div>
<div>
<i><b><br /></b></i></div>
<div>
These are a widely used tool, extensively used even in fully automated cutting rooms. They are used for the following purposes:</div>
<div>
<br /></div>
<div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>cutting exclusive garments in small quantities;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>cutting sample and prototype garments;</div>
<div>
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>cutting shortfalls in orders through miscalculation and rejection during production.</div>
<div>
<br /></div>
<div>
Hand shears vary in weight and blade length and can be designed for right hand or left hand operations. A typical pair of knitted fabric shears will have an overall length of between 20 cm and 30 cm.</div>
<div>
<br /></div>
<div>
In use the lower blade remains in contact with the cutting table surface underneath the fabric, while the upper blade operates above the fabric. The blades, while shearing along a line or curve, are never depressed hilly until the end of a cut, otherwise jagged cutting results. In cutting more than one layer of knitted fabric, great care must be taken to avoid distortion of the lower layer or layers. The more layers, the greater the risk of distortion. Most cutters treat two layers as the maximum that can be cut.</div>
</div>
<div>
<br /></div>
<div>
<div>
<b><i>Hand held power cutters</i></b></div>
<div>
<b><i><br /></i></b></div>
<div>
These essentially take two forms: the straight knife and the circular knife.</div>
<div>
<br /></div>
<div>
The straight knife is completely self contained except for its connecting electrical cable. An electric motor, and its associated gearing, drive a vertical blade in a vibrating manner rather like a woodworking jig-saw.</div>
<div>
The motor is mounted at the top, with a support column below on a flat plate base. The blade is mounted in front of the support column, the leading edge of which provides a slide track to guide the blade. The column is extremely thin to enable it to - pass through the fabric layers after the cut. The support base rests on the cutting table surface under the fabric and its underneath surface must be made of a low friction material. Roller balls can also be mounted on the base to aid ease of movement, and at least one manufacturer (Bullmerwerk) offers a knife with blown air lift, like a hovercraft.</div>
<div>
<br /></div>
<div>
For safety purposes a vertical guard is mounted in front of the length of the blade exposed above the lay. Also for safety purposes some cutters wear chain mail gloves on their free hand. Sharpening is carried out automatically on the machine when it is clear of the fabric.</div>
<div>
<br /></div>
<div>
Lengths of exposed blade, and thus cutting height, can vary from 12 to 25 cm. The operative manipulates and guides the machine through the fabric layers, along cutting lines, by grasping a centre mounted handle. Sometimes with heavier, taller machines a further handle is mounted on top of the motor.</div>
<div>
<br /></div>
<div>
In many cutting rooms in the underwear and leisurewear industry the straight knife is the tool used to cut multiple layers of fabric into garment portions. It is highly productive; the speed has proved difficult to verify, with different sources giving different figures, but an average consensus suggests<br />
5 m/min. The limitation on speed is the heating of the blade through friction. With some synthetic and with cotton this can be a problem.</div>
<div>
<br /></div>
<div>
With some wide widths of knitted fabric, the ability to get into the centre of a lay may present problems. Often two cutters work as a team one either side of the table. Having cut and removed the edge sections the centre can be repositioned nearer to the edge.<br />
<br /></div>
<div>
<b><i>Circular knives</i></b><br />
<b><i><br /></i></b></div>
<div>
The circular knife machines vary more widely in size than the straight knives. Their construction is similar, with the motor mounted on a support column and base plate. This time, however, the support column contains the axle and drive of a circular rotating blade. It is guarded at the rear and exposed on the front of the machine. Again, a centrally mounted handle is gripped by the operative to support and guide the machine through the work. On the smaller machines the motor itself forms the handle.<br />
<br /></div>
<div>
Circular cutters are available to cut through layer heights from under 2 mm up to 12 cm. The smaller cutters are, in reality, mechanical shears and are used for that purpose, either cutting single or double plys or cutting across fabric at the end of each layer (ply) to align them.<br />
<br /></div>
</div>
<div>
The larger cutters are used for cutting lays of from 6 cm to 12 cm. Because the blade is essentially cutting on the lower quadrant of the leading edge, when cutting on the maximum depth the upper layers are being cut in advance of the lowest layer by a length equal to the radius of the blade. This is immaterial when the cut is straight, but when a curve is attempted the lower edge is following a different curve from the top. For this reason circular cutters are generally used for splitting a lay up into portions, by cutting straight lines across and, where possible, down the fabric. The portions containing several parts of the garment are then dealt with by straight knife, band knife or die press.<br />
<br />
The circular knife cutters can operate at higher cutting speeds than the straight knives, having greater blade mass to absorb friction heat. Straight knives are heavy to push around and cutters soon tire and are prone to repetitive strain injury. Systems are available to support the weight of the cutter while retaining 360° rotation in the plane of cutting. In one example a two piece hinged arm is mounted on a vertical column at the side of the cutting table. The arm has freedom of movement above the cutting table. The arm supports the cutter and carries the majority of its weight while the cutting operative can move the straight knife freely within the reach of the arm without strain. The column can be moved along the edge of the table.<br />
<br />
Yet another system uses a pivoted counter-balanced arm mounted on a gantry that spans the cutting table. The weight of the cutter is reduced by the counter-balanced weight, without reducing the freedom of movement.<br />
<br />
<b><i>Band knife</i></b><br />
<br />
Portions of a lay can be moved from the cutting table to a secondary cutting area, where they are dealt with either by a band knife or a template cutter. This is generally only worth doing for relatively small items and items with intricate detail.<br />
<br />
The band knife employs a thin continuous blade that is driven and guided by pulleys in a 'C' frame. A portion of the blade is exposed as it passes through a flat working table on which the work is manipulated. The work itself is moved while the cutting blade remains stationary, so there is a limit to the weight/dimensions of the fabric to be sub-divided.<br />
<br />
The table surrounding the blade should have enough space around it to accommodate the sub-divided portions without impeding the work being manipulated. As the work is moved and presented to the blade by hand, band knife cutting is a particularly hazardous task and chain mail gloves should always be used.<br />
<br />
Fig. 3.3 shows a manual cutting system with automatic fabric laying up machine (spreader) cutting by straight knife marking with a fabric drill, and finally a band knife for the smaller and intricate pieces.</div>
<div>
<br /></div>
<div>
<div>
<b><i>Die cutting</i></b></div>
<div>
<b><i><br /></i></b></div>
<div>
Template or die cutters are popular with knitted fabric garment producers, particularly those making underwear. The template knives are embedded in compressible foam plastic. The foam/knife composite covers the whole lay and eliminates the need for a marker. The fabric lay is</div>
<div>
ed over the composite at the end of the cutting table away from position the spreading zone. The 'sandwich' passes through a hydraulic press that compresses the layers so that the knives cut through the fabric as the foam is deformed under pressure. Typical presses of this type are those made by Samco-Strong of Leicester.</div>
<div>
<br /></div>
<div>
Die cutting is quick, very accurate and excellent for small components. Because the preparation of the die cutters is slow and elaborate, this is not a Quick Response process and is used for the mass production of slow change items such as underwear.</div>
<div>
<br /></div>
<div>
Fig. 3.7 shows a fully automatic system with cloth roll magazine for changing fabric, automatic spreading, lay storage on pallets, air cushion table, and a die cutting machine.</div>
<div>
<br /></div>
<div>
<b><i>Automatic cutting</i></b></div>
<div>
<br /></div>
<div>
Automatic cutters are being introduced into firms making fully cut knitted garments. They are a natural consequence of the computerised pattern making, grading and marker making. Marker information can pass directly to the local computer controlling the cutting machine, or can be conveyed via stored' instructions on disk.</div>
<div>
<br /></div>
<div>
Despite experiments with water jets, laser beams and plasma beams, most auto cutters depend on vibrating straight knives. The knife is carried in a cutting head mounted on a gantry that straddles the cutting table. The knife can rotate through 360° below the head; the head can move freely across the gantry; and the gantry can move on rails along the length of the cutting table. Cutting can therefore take place in any direction over the whole surface of the table (Fig. 3.4).</div>
<div>
<br /></div>
<div>
The tables themselves are specially constructed so that the surface will support the lay and yet allow penetration by the knife through all the layers. Usually such tables have a surface of closely packed nylon or similar plastic bristles (Fig. 3.4).</div>
<div>
<br /></div>
<div>
Spreading is invariably carried out on another table or tables, but sometimes the spreading table is an extension of the cutting table so that a flow pattern is established.</div>
<div>
<br /></div>
<div>
Fig. 3.4 shows an automatic cutting line with cloth roll magazine changer and automatic spreading on to an air cushion table to aid the movement of the lay on to the bristle vacuum cutting table. Cutting is with a CNC-system 2000 auto cutter. The cut portions are assembled into bundles from an end work table.</div>
<div>
<br /></div>
<div>
On one of the Bullmerwerk System 2000 versions, the bristle mat is itself a conveyor.</div>
<div>
<br /></div>
<div>
Essential to the operation of automatic cutters is that the lay remains compact and undisturbed by the progress of the knife at high speed, and by the current of air associated with motor cooling etc. To this end an important feature of automatic cutting tables is that the lay is controlled by an under-table vacuum, maintained by very high powered air pumps.</div>
</div>
<div>
<br /></div>
<div>
<div>
For example, on Gerbers S-95 table for low and medium ply cutting (up to 10 mm), maintaining the vacuum on a working surface of up to 2 m by 3.6 m requires 30 KVA (kilo volt amperes). On the Gerber 5-91 for plys up to 76 mm on a similar area 70 KVA is required to maintain the vacuum.</div>
<div>
<br /></div>
<div>
The surface of the lay is covered with a plastic film or special paper to contain the vacuum. The lay itself compresses under the vacuum and any movement between plys is eliminated completely. </div>
<div>
Cutting speeds are high. Different makers of machines quote up to 20-30 m/min. Such speeds refer to low ply heights or even single layer cutting. On maximum heights with difficult fabrics cutting speeds are reduced and on knitted fabrics are more realistically between 8 and 16 m/min.</div>
<div>
<br /></div>
<div>
Blade heating is the limitation on cutting speed and must be avoided to reduce the risk of fusing or scorching. The cutting heads incorporate automatic blade sharpening.</div>
<div>
<br /></div>
<div>
It can be argued that cutting speeds are irrelevant, and that the gains of automatic cutting lie in the ability to eliminate marker making and to change cutting, fabric type, height of lay, length and width of fabric, etc., to enable a manufacturer to engage in Quick Response.</div>
<div>
<br /></div>
<div>
Some manufacturers producing 'high return' articles in jersey fabrics find it economical to cut single or double layers of fabric automatically and claim that the cost is lower than hand cutting.</div>
<div>
<br /></div>
<div>
Table dimensions of automatic systems are relatively small: 2 m, 2.4 m,</div>
<div>
3 m and 3.6 m are common lengths, and 1 or 2 m widths are usual.</div>
<div>
<br /></div>
<div>
Knitted fabrics, like wide woven fabrics, need subdividing longitudinally. Systems are available to carry this out during the spreading process. </div>
<div>
<br /></div>
<div>
<b>Summary</b></div>
<div>
<b><br /></b></div>
<div>
All the cutting methods discussed are used in the fully cut knitted garment industry. All have a valid role to play in particular situations and are tools by which cutting room managers can respond to the ever varying demands of the market.</div>
<div>
<br /></div>
<div>
The balance between low capital cost/high labour cost and high capital cost/low labour cost is complicated by the demands of Quick Response. In this section of production in particular, high output potential associated with high capital cost, is not linked inextricably with mass production.</div>
</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-29882008690030232302017-02-10T22:04:00.003-08:002017-03-01T03:24:34.644-08:00Integral Garments<div dir="ltr" style="text-align: left;" trbidi="on">
Right from the beginning of knitting by hand, garments were generated and constructed 'in the round'. Some of the earliest garments known are socks produced in Egypt during the Coptic era of the 4th and 5th centuries AD. These are constructed without seams, of closed loops, and display all the techniques of the integral garment. Some are very complex in the manner in which the heel pouch is generated and in the inclusion of separately knitted toes (digital socks) (Fig. 6.1).<br />
<br />
Dorothy K. Burnham in Textile History analyses several socks that form part of the Walter Massey collection in the Royal Ontario Museum, Toronto. She convincingly reasons that such articles were formed using a stitching technique, i.e. single needle knitting. Because they are formed of loops they are truly knitting but do not prove the existence of the two needle hand knitting technique contemporaneously, nor do they shed light on when two needle knitting started.<br />
<br />
Medieval caps, gloves, socks and hose were all knitted without seams and to approximate the shape of the human body, allowing for stretching of the fabric to provide exact fit where required. Later the upper body garments knitted by fishermen and their womenfolk on the northern coastlines were also produced without apparent seams.<br />
<br />
Michael Pearson in Traditional Knitting repeats the advice given to him by Shetland Island knitters: 'Never ever sew when you can knit. After all most people hate stitching the knitted pieces together. Knitting in the round, together with the grafting of seams, does away with this tiresome chore'.<br />
<br />
In terms of the techniques used in sock, glove and hat knitting, the ganzey knitters cheated. Their technique involved knitting the body of the garment in the round from the bottom up. At the yoke the knitting was either split into front and back knitting, or continued in the round to te shoulder, reserving the front neck and the underarm gusset stitches on the way. The back and front shoulders were brought together and knitted off (cast off), and the sleeves were knitted by picking up the gusset stitches and walewise loops down the selvedge around the armhole.<br />
<br />
Where the yoke is knitted in the round, the armhole apart from the gusset is cut and stitches picked up rather further in from the edge. Michael Pearson describes such a jumper as a classic Fair Isle pullover, where the extra yarn is generated and stored at the cutting line and subsequently worked into the arm join of the finished garment.<br />
<br />
Variations of these techniques include the 'grafting' of shoulder seams, and of sleeves knitted in the round in the conventional way from cuff upwards, to the armhole of the body.<br />
<br />
Grafting is a sewing technique in which a row, or course, of loops is generated by stitching two raw edges together. Frances Hinchcliffe, describes the construction of a child's jacket in Crafts magazine, July/ August 1982. The jacket is of 17th century English origin and has been constructed in an almost identical manner to the ganzey tee hr previously described, except that it has no underarm gussets and the sleeves ate 'set-in' but do not have any sleeve head shaping.<br />
<div>
<br />
Hand knitting became extremely popular towards the end of the 19th century and continued into the early 20th century. It is probably true to say that this period represented the zenith of the craft. During this period Weldon's Practical Needlework magazine was published. This was very influential and in its knitting series contained complete practical instructions to produce any knitted article from Smyrna rugs to knitted garters for ladies. The vast majority of the garments illustrated are integrally knitted and display all the techniques that can he used to generate shape and avoid seams and cutting.<br />
<br />
<b>Basic techniques</b><br />
<br />
The basic techniques of integral knitting are:<br />
<br />
<ol style="text-align: left;">
<li>course shaping (flechage); </li>
<li>wale shaping;</li>
<li>tubular knitting;</li>
<li>running-on;</li>
<li>change of stitch type;</li>
<li>casting off.</li>
</ol>
<b>Course shaping</b><br />
<br />
In machine knitting the term flechage (French for arrow or wedge) has been recently adopted to describe course shaping. It has also been known as the 'beret' principle of knitting. The principle is simple in that the length of the courses being knitted is diminished or extended successively. This usually takes place on one side of the knitting but can occur on either side, both sides, or indeed partial courses can he produced-anywhere on the width being knitted, or the construction can occur within a tube. No loops are lost by casting off or pressing off (dropping); all loops are stored (held) to knit at a later stage. The technique in fact can be alternatively described as knitting in which wales contain differing numbers of loops. Most of the knitting contains the same number of wales throughout.<br />
<br />
There are two alternative methods of construction (Fig. 6.2):<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>The number of loops knitted diminishes in every row. This gives a smoother, unstepped line, but where diminution is by more than one loop small floats occur.<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>The course diminishes every two rows. No floats occur but the construction has steps, and small holes can result when knitting on all wales is recommenced.<br />
<br />
<b>Wale shaping</b><br />
<b><br /></b>
Wale shaping describes knitting in which the number of wales is reduced or increased internally within a flat piece of fabric or a tube of knitting. The number of courses essentially remains the same (Fig. 6.3).<br />
<br />
<b>Tubular knitting</b><br />
<b><br /></b>
Tubular knitting is created when the constituent thread or threads of the fabric knit spirally. Tubes are particularly useful for clothing the human body as it is made up essentially of cylinders. Tubes feature prominently in integral garments.<br />
<br />
<b>Running-on (picking up)</b><br />
<b><br /></b>
This describes the process whereby knitting is commenced on the edges of previously formed knitted fabric. Mostly the edges involved are selvedges, but one of the common uses of this technique is in fully fashioned knitted panels which are commenced on the course-wise edge of previous knitted ribs.<br />
Running-on describes the machine knitting process of placing course loops or selvedge loops on to the needles of a knitting machine. Portions of knitting can be created perpendicular to previously formed Portions, or with a different number of wales from one another.<br />
<br />
<b>Change of stitch type</b><br />
<b><br /></b>
This process has already been described in cut stitch-shaped knitting. Essentially changes of fabric type between adjacent portions of a garment can generate shape. Such shapes can he horizontally, vertically or otherwise disposed to the garment.<br />
<br />
<b>Casting off (knitting off)</b><br />
<b><br /></b>
This describes the process of structure sealing the last knitted course of a piece of fabric. Up until recently this technique had been limited to hand knitting with pins or hand operated knitting machines, but the Shima Seiki company have introduced a mechanism for their model that performs this function.<br />
<br />
<b>Machine knitted integral garments</b><br />
<b><br /></b>
All the techniques discussed above are available to the machine knitter, but unfortunately not all on the same type of machinery. Some garments have traditionally been produced as essentially integral garments: half hose, hose, berets and gloves. It is only relatively recently that machinery capable of knitting upper body garments in one piece has been introduced.<br />
<br />
William Lee's hand frame produced essentially flat fabric, and its component product, hose, was fully fashioned and seamed. However it was capable of knitting three dimensional shapes by course shaping aided by selective pressing, or by wale shaping using loop transfer techniques: It is not known whether early frames used either of these methods, although gloves and hats were produced from early times.<br />
<br />
<b>Berets</b><br />
<b><br /></b>
The traditional beret is an apparently seamless floppy hat made of wool or wool with other animal hairs. The shape varies little between sizes and different makes, the overall concept being bag-like with a close fitting head-band broadening out to a larger diameter before closing shallowly to the crown. The beret resembles in form and shape the medieval caps mentioned at the beginning of this chapter. The modern machine knitted version originated in France but has spread world-wide, being particularly Popular as military headwear.<br />
<br />
The beret shape is knitted on specialist single needle bed flat machinery, with latch needles selected by a peg drum. Above the needles are mounted sinkers to control the loops during knitting of the complex shapes.<br />
<br />
The beret is knitted in plain fabric, its three dimensional shape formed by the consecutive knitting of up to 20 course shaped wedges. commences on the full width required and after two courses the length course diminishes by a fixed number of loops every two courses. When only a predetermined small number of loops arc being formed the cycle, is repeated by knitting on the full width again. With each succeeding wedge the form of the knitting bends round through an arc, but with the head hand side restricted into a cylindrical shape.<br />
<br />
After the last course is knitted the fabric is linked to the first course knitted. Both single chain stitch and double chain stitch are used. The blank is then milled, dyed, dried and blocked. The latter process k common in millinery and involves steaming the shape of the hat using a form. Sometimes a brushing is given to the finished form. In recent times a wide range of millinery has been produced using the beret principle combined with thermoplastic fibres. It is difficult to distinguish hats produced by three dimensional knitting from those produced by conventional means, including three dimensional weaving.<br />
<br />
<b>Half hose or sock</b><br />
<b><br /></b>
The sock is now a ubiquitous product world-wide and is worn by both sexes and all ages. Because of the nature of the production machinery the construction varies little, particularly in terms of the generation of shape. Socks very in leg length considerably, from just below the knee (true half hose) to ankle length. The small diameter circular knitting machines that produce socks impose a limitation on their structure in that it is not possible to increase the total size/number of wales of the tube of the sock. This means that there is no facility for wale shaping. The shape of the sock is created by stitch-shaping and course-shaping.<br />
<br />
The sock is commenced at the ankle/leg opening with a welt and rib construction designed to grip the leg and prevent the collapse of the sock to a loose bundle around the ankle (often unsuccessful). Most modern socks also contain elastomeric threads in the rib to aid the grip.<br />
<br />
After the 1 x 1 or 2 x 2 rib the structure is changed to either plain fabric or a broad rib. This section of the sock is often decorated with jacquard, semi-intarsia, wrap stripe embroidery or structural design. At the level of the heel the instep half of the knitted tube is held while knitting is continued on the heel half reciprocally. The length of the course is reduced by one loop on each side every two courses.<br />
<br />
When the length of the course is 1/16th of the circumference of the tube the process is reversed and the length of the course is increased by one loop on each side every two courses, picking up the reserved loops in the process. When the course reaches half the circumference of the tube, reciprocal knitting ceases and the spiral of the tube is recommenced.<br />
<br />
Fig.6.4 shows a course by course account of this process, albeit in the flat, with the structure exploded along the turning lines of the heel pouch.<br />
<br />
After the knitting of the foot tube the toe is generated in the same manner as the heel pouch. The sock is completed by a single seam joining the two half circumferences of the tube together.<br />
<br />
Recently the Shima Seiki flat machines of the type that make gloves have been adapted to produce half hose. The socks produced on the Shima Seiki SPF are entirely seam free and can be produced in conventional form, fully digital (five toes) or partially digital.<br />
<br />
<b>Upper and lower body garments</b><br />
<b><br /></b>
The arguments for and against integrally knitted garments were aired in Chapter 1, where it was pointed out that most of the resistance to the introduction of raw material and labour saving garment forms lay in the socio-economic objections rather than the technical.<br />
<br />
There are technical limitations to what can be achieved; not every garment type/shape currently produced by cutting and sewing can be achieved in three dimensional knitting. But within the known possibilities only the surface has been scratched so far.<br />
<br />
Much work has been carried out by the manufacturers of flat knitting machines into the three dimensional generation of garments. Here mention must be made of work carried out in the early 1980s by Michael<br />
<br />
Dicks, Michael O'Brien and others at the Dubied Knitting Machinery Co in Leicester, and of the work currently being undertaken by the Shima Seiki Co.<br />
<br />
To illustrate some of these possibilities several garments are discussed here and some historical background given.<br />
<br />
<b>Garment 1</b><br />
<b><br /></b>
The first garment is an intermediate one, intermediate that is between fully fashioned and integral. It certainly saves cutting waste and reduces sewing labour but is knitted in a flat form.<br />
<br />
The garment is a short ladies jacket knitted in a half cardigan rib construction with fronts and back knitted together and with neck revers and armholes shaped by fashioning (Fig. 6.5). The garment is a development design of the Shima Seiki Company and is produced on a seven gauge model SEC 202 FF M type. I do not propose to examine the details of the machine knitting program that achieved this article, although a brief description of the techniques involved is appropriate.<br />
<br />
To fully fashion on a V-bed flat machine, loops are transferred selectively at the extremities of the knitting from the bed they have been knitted on to the needles on the opposite bed. The beds then move laterally to one another (racking) and the loops are transferred back, this time to different needles, either reducing or expanding the knitting width. Fig. 6.6 illustrates this figuratively.<br />
<br />
Such movements are simple when the fabric is being knitted on one bed only but become more difficult when knitting rib constructions on both beds because there are no empty needles, other than the single ones at the outer edge of the knitting width, to which to transfer. The usual way of overcoming this problem is by knitting on only alternate needles on each bed, thus freeing needles to be used as temporary parking places for loops. This is known as half gauging. On simple fully fashioned rib garments, often only the outer three or four needles are arranged in this way, but on this garment with its internal armhole fashioning the whole knitting width is half gauged.<br />
<br />
The only waste generated with this garment is the roving courses at the top of the shoulder portions. The only seaming required is:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>overlocking and taping of the shoulders;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>sealing of the back neck with double chain stitch;<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>button holding and button sewing.<br />
<br />
Further development of this garment could involve auto casting off of part or all of the shoulder and back neck on completion; and the retention of the loops of the underarm shaping while continuing to knit the front and back yokes, with subsequent knitting of sleeves. Such sleeves would require partial seaming of the head into the armhole and a top sleeve seam. Development into a raglan could eliminate the head seam. I will leave the reader to imagine the innumerable possibilities that this particular garment idea presents.<br />
<br />
<b>Garment 2<span class="Apple-tab-span" style="white-space: pre;"> </span></b><br />
This garment was the invention of the late Harry Wignall, Head of the department the of Textile Technology, Leicester Polytechnic. The concept is very simple, that of knitting a tube of fabric with part way along it two opposing heel type pouches. The fabric is cut in a wale line from one end of the tube to the centre of each pouch, the cut portions lowered to a position at 90° to the tube, and the basic shape of a raglan sleeved jumper is created (Fig. 6.7).<br />
<br /></div>
<div>
<div>
The subsequent shape requires cutting at the neck and top arm with top arm/shoulder seaming, neck finishing and rib attachments at waist and cuff. There is some saving of cutting waste with this garment but the extra seaming operations probably equal, if not exceed, those involved in a conventional cut garment of this type.</div>
<div>
<br /></div>
<div>
Bentley Engineering constructed a machine to this pattern and several were sold for the production of school jumpers. It is rather a dead end concept in that little if any pattern and shape development is possible; nevertheless it can be argued that this is an important link in the chain of integral garment ideas in that it uses course shaping in a very novel way and while it shows that integral garments are possible on circular machinery it is not a versatile route.</div>
<div>
<br /></div>
<div>
<b>Garment 3</b></div>
<div>
<b><br /></b></div>
<div>
This concept is one of the most promising methods of knitting integral garments on V-bed flat machines. The principle is relatively simple: tubes are knitted simultaneously for the body and sleeves of a garment. These</div>
<div>
<br /></div>
<div>
are spaced appropriately on the needle bed: sleeve—body—sleeve (Fig.6.8) the knitting of the body and sleeves progresses these needles are introduced in the sleeve sections one at a time to form the underarm widenings. Eventually the sleeves meet with three tubes is merged into one.</div>
</div>
<div>
<br /></div>
<div>
<div>
Narrowing now commences, involving the sections of knitting f associated with the sleeve tubes. The whole of the sleeve sections are moved over progressively to form a raglan sleeve head on each side of the body. Eventually the diameter of the tube diminishes to neck size. It is possible to shape the front neck during the knitting process, retaining the loops for subsequent knitting of a neck rib when the ac neck has been pressed off. Such a collar requires turning in at a fold and attaching to the back neck and inside front neck with mock linking.</div>
<div>
<br /></div>
<div>
Waistbands and cuffs can be formed by turning welts with Hind overlock or linking seams, or ribs can be overlocked or linked on. it possible to preform ribs on the knitting machine by knitting first the front ribs on alternate needles, i.e. half gauged, then transferring loops from the back bed to the front where they are stored on say odd needles while the back rib is knitted on even needles and eventually transferred to the hack bed. When both back and front ribs have been knitted, the tubular knitting is commenced.</div>
<div>
<br /></div>
<div>
It is not necessary to commence knitting body and sleeves at the same time; body and sleeves are rarely of the same length. It has been suggested that ribs be pre-formed and run on to the needles of machines in much the same way as ribs on to a fully fashioned machine using a point bar. While this presents manipulative difficulties with the current designs of flat machines, it would enable a wider range of rib types to be attached to the garment.</div>
<div>
<br /></div>
<div>
Because of the manner of fashioning by loop transference between beds, already described for Garment 1, garments of this type are essentially produced on half gauged machine set-outs. There is another machine type, however, where this is potentially unnecessary. Such machines have a loop transfer bar or bars situated above the needles, capable of lifting loops off the needles, racking, and replacing them in a changed position. The machine builders ABRIL make such a machine currently and several builders, including Stoll and Universal, have previously made such machinery. It is not known whether they actually used them for seamless garments but the potential is there for future development.</div>
<div>
<br /></div>
<div>
The production of tubular seamless garments was patented in the name of Robinson and Chell for Courtaulds Ltd in 1965. Courtaulds themselves did not use this idea to produce commercial garments and the patent inhibited others from developing the concept.</div>
<div>
<br /></div>
<div>
While the garments are basically knitted in plain fabric it is possible to decorate the fabric with a wide range of structural and colour possibilities using knitting, missing, tucking and striping as well as intarsia. The garment described has raglan sleeves but it is possible to generate a wide range of different sleeve heads of the set-in type.</div>
<div>
<br /></div>
<div>
While this type of garment can be made on present day machinery, it would probably be best exploited if special machinery were designed to iron out some of the problems that arise.</div>
</div>
<div>
<br /></div>
<div>
<div>
<b>Panty-hose</b></div>
<div>
<b><br /></b></div>
<div>
Panty-hose have been the subject of several efforts to produce integrally knitted versions. The Pretty Polly 'Banana' type (Fig. 6.9) was an early introduction (1960s) of moderate success. The garment was knitted as a single tube from toe to toe, with the centre sections of the tube forming the panty part of the garment. A split was made in the widened panty section on one side along a single wale. This slit opened out to form the waistband but had to be finished with an elastic insertion seam. The toes were of the 'closed' variety and so required no seaming. Because of the limitations of the size of the panty section satisfactory fit could only be achieved on smaller sizes, and the idea never became fully exploited.</div>
<div>
<br /></div>
<div>
A more recent development by the Italian machine builder Saveo-Matec produces a whole panty hose in a novel manner (Fig. 6.10). Two open top, small diameter hose machine cylinders are mounted on the same machine frame. The upper cylinder is inverted over the lower one, in a similar configuration to a double cylinder 1/2 hose machine. Both cylinders knit simultaneously, each producing one leg of the panty hose. Knitting commences at the waistband of the panty portion, each cylinder knitting an elastomeric turned welt. The two tubes, one inside the other, are slit at the position down a single wale, starting from the first course. On either side of the slit, selected needles share the yarn on some of the courses, splicing the two tubes together and forming a 'knit seam'. This splicing continues for a small number of courses after the slitting, to form the lower extremity of the seam. The legs. are knitted one inside the other and have open toes that are sealed with an Overlock seam as a post-knitting operation. All sizes are possible on this most unusual garment, which must be turned to draw the inner leg out of the outer.</div>
</div>
<div>
<br /></div>
<div>
<div>
For a much fuller account of the knitting process, and the ultra/ assembler machine read Modig (1988).</div>
</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-62990587097918238102017-02-03T23:38:00.003-08:002017-03-01T03:24:34.679-08:00Fully Fashioned Garments<div dir="ltr" style="text-align: left;" trbidi="on">
Shaping by fully fashioning involves the movement of a small number of loops at the selvedge of the fabric. Such movement reduces or increases the total number of loops being knitted. The terms used in the industry for such movements are narrowing and widening, and collectively fashioning.<br />
<br />
When narrowing, the innermost loop of the group being moved combines with the loop adjacent to it. Fig. 5.1 represents two loops being moved by one loop space, thus losing one loop at the edge. It is possible on plain fabric to move the edge loops more than one needle space, losing more than one loop at the edge. In the fully fashioned industry these are known as 'needle narrowings' e.g. two needle narrowings where the outer group are moved in two needles. Such multi-loop narrowings produce small puckers where the loops combine. The number of loops in the group being moved varies from three to seven, with finer fabrics tending to involve more loops than coarser fabrics.<br />
<br />
With successive fashioning the wales at the outer edge of the fabric follow the shape of the selvedge, giving the characteristic signature of fully fashioned garments. There is a utilitarian reason for the movement of several loops rather than just one: it allows seaming to follow a wale line throughout the garment, giving neatness of assembly.<br />
<br />
In widening, the movement outwards creates a space adjacent to the innermost needle of the group, where a new wale may start (Fig. 5.2). The empty space, followed by the tuck loop formed at the next knitted course, leaves a hole in the fabric. It is usual in commercial practice to fill this hole by moving a previously knitted loop to commence the new wale. Such holes restrict the widenings to single needle only (Fig. 5.3).<br />
<br />
Fashioning is not restricted to plain fabric only; rib fabrics are increasingly the subject of fully fashioning. Particularly suitable for shaping in this way are the cardigan fabrics containing tuck loops and broad ribs.<br />
<br />
<div>
<div>
<b>Shape Generation</b></div>
<div>
<b><br /></b></div>
<div>
As already explained, fashioning involves the progressive narrowing or widening of a piece of fabric at the edges while maintaining perfect selvedges. The shape generated depends on the number and size of the loop movements, and their frequency in relation to the loop density of the fabric involved.</div>
<div>
<br /></div>
<div>
Loop density of fabric is measured in terms of number of wales/unit length, and number of courses/unit length. In plain fabric a normal ratio for each is 1 : 1.3. However, as particular fabrics vary around that, it is usual to calculate it more accurately.</div>
<div>
<br /></div>
<div>
The best approach to calculating fully fashioning is to regard all shapes, including curves, as right angled triangles with a vertical dimension of the number of courses involved, and a horizontal dimension equal to the number of loops lost or gained by fashionings. The hypotenuse represents the line taken by the selvedge of the fabric.</div>
<div>
<br /></div>
<div>
Fig. 5.4 shows three fashioning situations represented on graph paper, the first involving a narrowing by one loop every two courses (Fig. 5.4 a), the second a narrowing by one loop every course (Fig. 5.4 b). The graph paper is ruled in the ratio 1 : 1.3 so that the angles generated are near to reality. In present day commercial practice narrowing is rarely carried out On'every course. A one loop narrowing every course is translated into a two loop narrowing every two courses (Fig. 5.4 c).</div>
</div>
<div>
<br /></div>
<div>
<div>
The fashioning frequency of two loops every two courses is considered to be the maximum and therefore represents the lowest angle achievable by the fully fashioned process. Even at this frequency the edge of the fabric, the hypotenuse, is distorted because in reality it is formed out of the same number of courses as the vertical side of the triangle. R.W. Mills (1965) has shown that fashioning angles can be expressed mathematically, and further that the minimum angle that can be achieved is that on plain fabric produced by an effective fashioning (narrowing) of one loop every row. Apart from the practical difficulties of achieving angles below this, it must be borne in mind that the hypotenuse of the triangle formed is a distortion of the 'opposite side'. A piece of fabric narrowed by one loop every course will form at its edge a right angled triangle, the opposite side of which is in line with the wales, and the adjacent side in line with the courses (Fig. 5.5).</div>
<div>
<br /></div>
<div>
As the narrowing is effectively one loop every row, the adjacent side will contain the same number of wale loops as the opposite side contains course loops. As the normal ratio for courses/unit length to wales/unit length in a relaxed plain fabric is in the order of 1:1.3, the adjacent side can be given a dimension of 1.3, and the opposite a dimension of 1.</div>
<div>
The fashioning angle can be determined trigonometrically:</div>
<div>
<br /></div>
<div>
1 </div>
<div>
______ = tan θ</div>
<div>
1.3</div>
</div>
<div>
<br /></div>
<div>
0.76932 = tan θ</div>
<div>
<div>
0 = 37°34'</div>
<div>
<br /></div>
<div>
This angle is for all practical purposes the lowest that can be achieved and sets the limitations for shape generation by fully fashioning.</div>
<div>
<br /></div>
<div>
The angles of other fashioning frequencies on plain fabric can be similarly calculated using the general formula:</div>
<div>
<br /></div>
<div>
Fashioning frequency</div>
<div>
_____________________ = tan θ</div>
<div>
1.3</div>
<div>
<br /></div>
<div>
<br /></div>
<div>
<i>Example</i></div>
<div>
<br /></div>
<div>
Let fashioning frequency be one loop every four courses, then:</div>
<div>
<br /></div>
<div>
4</div>
<div>
— = tan θ = 3.077</div>
<div>
1.3</div>
<div>
<br /></div>
<div>
θ = 72°</div>
<div>
<br /></div>
<div>
A common usage of the two loops by two course narrowing is to generate the shoulder slope on the body portions of a classic set-in sleeve garment (Fig. 5.6).</div>
<div>
<br /></div>
<div>
If both front and back shoulders were fashioned the resulting slope would be too great, so only the back is fashioned, the front remaining straight and terminating in a course. This throws the shoulder line seam to the back of the garment and fortuitously produces a very smooth profile.</div>
<div>
<br /></div>
<div>
While it is possible to work out angles from frequencies, and vice versa, most 'statements' (knitting instructions) are in fact worked out from paper patterns prepared to achieve a particular design, the fashioning frequencies being calculated directly from dimensions of the pattern and known fabric 'qualities' (wales/cm, courses/cm).</div>
<div>
<br /></div>
<div>
Calculating a fashioning frequency from given dimensions involves the following simple formula (Fig. 5.7):<br />
A x w.p.cm</div>
<div>
F = _____________ 1.</div>
<div>
D<br />
<br /></div>
<div>
C = B x c.p.cm 2.<br />
<br /></div>
<div>
A = horizontal dimension of loss of loops, in centimetres.</div>
<div>
B = vertical dimension of loss of loops, in centimetres.</div>
<div>
C = number of courses in B centimetres.</div>
<div>
D = number of loops narrowed or widened by, at one fashioning.<br />
(Widening is inevitably by one loo p only.)</div>
<div>
F = number of fashionings.</div>
<div>
c.p.cm = courses per centimetre.</div>
<div>
w.p.cm = wales per centimetre.</div>
<div>
The fashioning frequency is determined thus:</div>
</div>
<div>
<br />
<br />
Freq. = C/F <br />
<span class="Apple-tab-span" style="white-space: pre;"> </span> 3.<br />
or<br />
<br />
Freq. = C/ F + 1 4.<br />
<br />
Formula 4 allows the shaped section to begin by knitting before a fashioning, and end with knitting after a fashioning. Formula 3 is appropriate when the fashioning sequence is followed by further knitting.<br />
<br />
Example (Fig. 5.8)<br />
<br />
The fashioned portion of the piece of fabric in Fig. 5.8 can be represented by the triangle in Fig. 5.9;</div>
<div>
<br /></div>
<div>
c.p.cm = 6.<br />
w.p.cm = 5.<br />
<br />
Number of courses = 10 x 6<br />
= 60<br />
3 x 5<br />
Number of fashionings = ______<br />
1<br />
= 15<br />
<br />
60<br />
Frequency of fashioning = ______ = 4<br />
15<br />
<br />
The whole of the piece of fabric can be represented by a 'statement':<br />
<br />
Number of loops at start = 15 x 5 = 75<br />
<br />
Fashioning on RH side<span class="Apple-tab-span" style="white-space: pre;"> </span>= 15 times at four course intervals, over one<br />
needle space, or 15 x 4 x 1<br />
<br />
Number of loops at finish = 12 x 5 = 60<br />
<br />
These simple formulae deal with whole numbers only as neither a knitted course nor a wale can be subdivided. Where C is not exactly divisible by F a remainder is created. This remainder of a number of courses can be distributed so that a proportion of the fashioning intervals are increased by one.<br />
<br />
<i>Example</i><br />
<i><br /></i>
Number of courses = 33<br />
Number of fashionings = 6<br />
Using formulae 3 frequency = 33/6<br />
= 5 remainder 3 courses<br />
Distributing these remaining courses produces two differing fashioning frequencies:<br />
<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>3 fashionings @ S course intervals.<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>3 fashionings @ 6 course intervals.<br />
<br />
Usually designers of fully fashioned garments avoid such situations by simplifying shapes to contain whole number frequencies.<br />
<br />
<b>Shapes</b><br />
<b><br /></b>
Commercial garments produced by the industry using straight bar knitting machinery tend to be of few types and of relatively simple shapes. This may reflect a continuing market demand for 'classical' knitwear, but there is little doubt that the full scope of shaping is not exploited in Practice. There is also a built in conservatism within the fully fashioned industry which maintains convention fairly rigidly. Most straight bar knitting machinery is built with a limited product in mind, in contrast with V-bed knitting machinery that is built for versatility.<br />
<br /></div>
<div>
<div>
There are three basic upper body styles in general production: raglan sleeve, set in sleeve and saddle shoulder. Both cardigans and jumpers are produced in all three, with variations of the neck lines (Fig. 5.10) into round neck, V-neck, turtle neck, polo neck, shirt neck, and occasionally halter neck and slash neck. Both jumper and cardigan styles are produced in all the variations.</div>
<div>
<br /></div>
<div>
The other variable in the shape of garment produced is the treatment of waistbands and cuffs. Because of the limitation of most straight bar knitting machinery in producing fully fashioned garments in plain fabric, rib waistbands are produced on separate V-bed knitting machines. This poses a production disadvantage but is a very definite design advantage: not only can ribs of varying types of construction — 1 x 1, 2 x 2, 3 x 3, 2 x 1 etc. — be attached, but the width of rib attached, and therefore the balance of rib to body, can be varied by a device known as doubling. This, is the Malting of two rib loops on one transfer point at a predetermined frequency, when preparing the ribs for transfer to the straight bar</div>
</div>
<div>
<br /></div>
<div>
<br />
<br />
<br />
<br />
<br />
<br />
Fully Fashioned Garments<br />
machine when beginning the knittin<br />
73<br />
g of a panel. This merging two rib wales into one bod <span class="Apple-tab-span" style="white-space: pre;"> </span>s has the effect of<br />
Another method of producin louswe.daiestiblel or cuff <span class="Apple-tab-span" style="white-space: pre;"> </span>I<br />
rib construction at all. 'Turned wgealeffis the term used when the extreom.viteieas of the garment waistband and/or • are turned back on themselves. This is done at the start of knittin thceu panel and involves turning back the first two or three inches of fabgric and running the sinker loops of the first knitted course on to the needles of thee machine so that they arc construction does not pull in the fabric<br />
incorporated into the fabric on the f einxhtanctymwrsacy ra)fndknisitttiisnegci oSnucshhirat styled garments or at the hems of full fashioned skirts.<br />
<br />
As already mentioned, most <br />
possible to produce as are very stereotyped in their most garmye:<br />
construction. It is<br />
g rments that are unconventional but they are rarely seen in commercial prlod uction. The fully fashioned industry used to produce garments of similar complexity for underwear, shaping them to fit the contours of the body closely. Included in such garments were techniques that moved the product towards integral knitting, such as running on the wale selvedges so that the knitting changed direction, and internal fashioning.<br />
<br />
Fully fashioning has long been used on garments other than the ones described as being the products of the present industry with its straight bar bearded needle machinery. Most other fully fashioned garments are prodticed on hand flat knitting machinery, either V-bed or 'domestic' single bed machines of various sorts. Classifications include:<br />
<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>Ladies suits, jackets and coats knitted in milano rib in fine gauges The materials used are high quality wool yarns and mercerised cotton. Styles are very classical, appealing to the older woman, with great attention to detailing. This section of the industry is in decline.<br />
<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>Fully fashioned men's sweaters It has long been most economical to produce coarse gauge men's sweaters on hand flat machines. Such sweaters range from simple raglan sleeve styles in half cardigan, to complex sweaters involving loop transfer designs or cables. Particular, specialist lines include cricketing sweaters and 'ganzies' (fishermen's sweaters).<br />
<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>Fashion knitwear Since the introduction of low priced domestic knitting machines in the early 1960s, many small industries have established themselves in the production of garments of all types but with the common characteristics of high fashion content, Quick Response and small production runs. Most of the products of this industry fall into the fully fashioned category. Again this is an area where the new technology V-bed knitting machines are able to produce similar articles, and these will increasingly be available.<br />
<br /></div>
<div>
<div>
<b>Modern V-bed machinery</b></div>
<div>
<b><br /></b></div>
<div>
The introduction of computer controlled V-bed knitting machinery, its recent times is responsible for a widening of the range of fully-fashioned knitted garments, as well as the transfer of production of certain types of garment from traditional methods to the new technology.</div>
<div>
<br /></div>
<div>
Among new types of fully fashioned garments produced on this type of machinery are a full range of colour patterned and structurally patterned rib garments. Types borrowed from other production methods include Intarsia patterned garments of a complexity previously only achieved on hand flat machinery, and fair isle patterned garments only produceable by hand-knitting or on domestic knitting machines. The transfer of normal production from straight bar machinery is also taking place, particularly where the production is of garments containing expensive fibres such as cashmere. Arguments used for such transfer include quick response, little raw material tied up, short, economical runs, and capital costs not forming a major proportion of the cost of a garment.</div>
</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-85959414732327172762017-02-03T23:09:00.002-08:002017-03-01T03:24:34.721-08:00Cut Stitch-Shaped Garments<div dir="ltr" style="text-align: left;" trbidi="on">
In Chapter 2 the general principles of the production of cut stitch-shaped garments are outlined. Most cut stitch-shaped garments are upper body garments of the knitwear variety. Within this category a large variety of men's, ladies', and children's garments are produced in the form of jumpers, slipovers, cardigans, jackets and waistcoats. Most fashion knitwear falls in this category. The term fashion in this sense describes designs that are up to the minute, short-lived, appealing to younger age groups and mostly women's wear but including some men's wear. The term implies the opposite of classical.<br />
<br />
Other garments made by cut stitch-shaped techniques are some forms of ladies' vests, dresses and skirts. Knitted dresses in particular are very fashion dependent and appear on the market infrequently.<br />
<br />
The widest variety of stitch forms and colour pattern work also occurs in this classification, and these in fact form the main basis of a particular design. The shape of the garments is relatively simple, and while overall form in terms of the length of the garment and the relative looseness or tightness of fit are important, the main appeals are in the textile design content.<br />
<br />
Garments tend to be classified according to neck opening style and sleeve head attachment. The latter is more important as it determines the size of the knitted blanks and the economics in terms of raw material utilization. Neck openings are regarded as a variable option that can be carried out on a standardized overall body shape. Popular neck openings/ treatment styles for jumpers include round neck, V-neck, turtle neck, polo neck and shirt collar types (see Glossary). Most cardigans are given a simple facing that varies with the nature of the ribbing or stalling used. Other designs are achieved by rolled revers and collars.<br />
<br />
Economic considerations tend to impose limitations on the type of sleeve head shape used. With cut knitwear this limitation is mainly in the variations of set-in sleeve heads and drop shoulders. The sleeves for such shapes can be produced from smaller blanks than raglan or saddle shoulder types. Fig. 4.1 shows a comparison of blank sizes and the relative wastage levels for a set-in sleeve garment and raglan sleeved garment of similar size, shape and overall weight.<br />
<br />
While percentage wastage levels are useful in comparing garments made from different cut processes with those fully fashioned, they are of little use in assessing garments cut from the same sizes of blanks. The raw material cost of a cut stitch-shaped garment is solely dependent on the size/weight of the blanks from which it is cut. Within the blank it is quite irrelevant whether the waste is 25% or 35%, except from a moral standpoint. The shapes themselves are usually very simple for cut stitch-shaped garments. Side body line is invariably straight below the underarm, with constriction caused by rib waistbands at the lower end; length is variable and the 'waist' can be in any position from just below the bust to below crotch level. Sometimes, when fashion demands tight fitting knitwear, some shaping from underarm to waist is inserted.<br />
<br />
Sleeve heads are invariably symmetrical, as are front and back armholes on the body portions. The general fit of the garment over the contours of the body, and the articulations of the arms, depend almost wholly on the elastic deformation of the fabric. Darts are not generally used to generate bust shapes or upper back shoulder shaping.<br />
<br />
Important dimensions in determining the overall appearance of knitwear garments are (Fig. 4.2):<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>bust width, measured underarm;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>length, measured back neck to extremity;<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>sleeve head depth;<br />
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span>sleeve width;<br />
(5)<span class="Apple-tab-span" style="white-space: pre;"> </span>underarm sleeve length.<br />
<br />
Also of major importance to the overall fit, comfort and appearance is the angle that the sleeve makes with the body (Fig. 4.3). At 90° the sleeve/ body junction is very full and drapes, tending to pull the shoulder line downwards. At 75° the sleeve/body join is beginning to feel constricted. Most shoulder/sleeve slopes are of the order of 80° to 850.<br />
<br />
This angle can also be expressed as shoulder slope. That is the angle formed between a line projected from the neck, perpendicular to the centre body line, and the upper edge of the sleeve.<br />
<br />
Shoulder slope = 900 — body/sleeve angle<br />
<br />
The above measurements are the ones that are the most important in quality control procedures and are the basis for specification.<br />
<br />
If this so far appears restrictive of shape and fashion styles, that is not the intention. It is simply that this section caters for Quick Response fashion and almost anything goes in terms of garment definition and shape detail.<br />
<br />
<b>Cutting</b><br />
<b><br /></b>
Prior to making and cutting it is normal to subject the garment blanks to an open bed steam treatment. This has two objectives:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>to relax the blank and stabilize its surface;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>to regulate its size and shape.<br />
<br />
To ensure the second objective metal forms are often used, inserted into the tube formed by two flat blanks temporarily seamed together, or one wide flat blank folded and seamed, or the tubular blank from a circular machine. The blanks are then steamed with the forms in place. In the main, most cut knitwear is produced from acrylic yarns, it being generally uneconomic to cut wool, cotton or other natural fibres to waste.<br />
<br />
<div>
<div>
Acrylic fibres are very thermoplastic and great cart is needed, when the blanks are on the steam bed and hot, to avoid distorting them by undue handling. After steaming and cooling, acrylic fabrics are very stable and do not exhibit the dimensional instability of, say, cotton. When wool or cotton is used for cut knitwear it is often given an actual press at this stage to neaten and stabilize it.</div>
<div>
<br /></div>
<div>
Cutting is still mostly done by hand with shears on individual garment pieces. Cardboard pattern shapes are used and the cutting lines are chalked on to the fabric. Often such chalk lines are only approximate guides, it being more important to cut to a particular structural or pattern feature. It is also normal practice to cut along the wale line of the rib cuffs, waistbands or hems. Sometimes a tight specification demands that this is in a precise position, and the ribs are actually counted to achieve this.</div>
<div>
<br /></div>
<div>
Sometimes negative pattern shapes are used, i.e. the shape of the portion to be cut away rather than the shape of the garment. V-necks are commonly treated in this way, it being easier to align a small piece of card on what is quite an unstable surface.</div>
<div>
<br /></div>
<div>
The actual cutting takes place on a flat table of sufficient height that the cutter, who stands, feels comfortable and does not suffer back stress. Two body blanks are usually cut together, i.e. a front and back, or two sleeves. As already outlined these may already be in tubular form, or, if flat, tacked together. The body front and back are cut together for the sleeve insert and back neck; the body front is then cut for the neckline. If there is side body excess or length excess this is cut off initially.</div>
<div>
<br /></div>
<div>
To speed production, template or die cutters are used for large orders or when standardized shapes are used.</div>
<div>
<br /></div>
<div>
This involves two beds. On the lower one the garment portions are assembled, accurately aligned. The lower bed usually contains the cutting template, although it can be in the upper bed. The cutter itself consists of thin steel strips, razor sharp on one edge, embedded in a deformable plastic substrate. The steel strips define the outline of the garment and are specially made and assembled for each size and type of garment.</div>
<div>
<br /></div>
<div>
When the garment pile is ready to cut, the beds are aligned and pressure applied to force the template knives through the pile of gar¬ments. Safety is of prime importance and guards and two handed switches are fitted to prevent accidents. The device can handle up to eight pieces at a time. Front necks are usually cut out afterwards by hand. Separate machines are required to handle bodies and sleeves, and only one size can be cut at once.</div>
<div>
<br /></div>
<div>
Some firms use die cutters to cut single pieces of garments from blanks, i.e. front or back or sleeve. The usual practice is to fold the blank vertically down a centre line which is placed accurately on a mark on the lower bed. It is claimed that a dozen garments can be cut in seven minutes, not counting the time to change the knives. This is quick and simple as the knives merely slide off a plastic sheet, to be replaced with others.</div>
</div>
<div>
<br /></div>
<div>
<div>
The claim made for single garment piece cutting is high accuracy; there is a tendency for piles of fabric to distort under the pressure between the two beds.</div>
<div>
<br /></div>
<div>
<b>Hybrid cut/fully fashioned garments</b></div>
<div>
<b><br /></b></div>
<div>
Mention should be made of hybrids between cut knitwear and fully fashioned knitwear. There are two sorts, varying only in the method of shaping on the V-bed flat knitting machines: press-off shaping and held-stitch shaping. The end results are the same: eliminating the cutting stage and saving raw materials.</div>
<div>
<br /></div>
<div>
Modern computer-controlled V-bed flat knitting machines equipped with presser feet (stitch pressers) or with loop holding sinkers are capable of knitting without imposing take-down load on the fabric being formed. This allows loops to be dropped off needles at the edge of the fabric without the fabric disintegrating into ladders and holes. Such pressing-off can be used to generate a sleeve head shape, or a sleeve insertion hole, or to form raglan sleeves which otherwise, as already outlined, are uneconomic. The pressing-off can be done gradually, loop by loop or in steps. Trimming is usually left to the knives of the overlock machine.</div>
<div>
<br /></div>
<div>
The held-stitch technique involves holding the loops at the edge of the knitting and reducing in stages the of the course being knitted. No pressing-off takes place until the shape is completed and two or three edge rows have been knitted. This technique is particularly useful for set-in sleeve heads and shoulder slopes.</div>
<div>
<br /></div>
<div>
Such narrowing techniques can be combined with needle introduction widening for sleeves, and very large savings can be made. In spite of the obvious advantages of such techniques in economic terms, with the saving of raw material and cutting time, and little or no increase in knitting time, they are still not widely practised.</div>
</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-72474706972533848362017-02-03T21:44:00.002-08:002017-03-24T05:07:48.806-07:00Fully-Cut Garments<div dir="ltr" style="text-align: left;" trbidi="on">
On the whole the component shapes of knitted garments are simpler than those made of woven fabrics. This applies even when the garments are made of jersey fabrics and are intended to occupy the same role as woven fabric garments, e.g. jersey dresses.<span class="Apple-tab-span" style="white-space: pre;"> </span><br />
<br />
This simplicity of shape arises out of the natural extensibility of knitted fabrics that enables three dimensional forms to he generated by deformation. Such forms in woven fabric are obtained by darts, tucks, gores etc. To illustrate this, Fig. 3.1 shows a raglan sleeve head where the shape of the shoulder is generated in woven fabric by cutting, whereas in knitted fabric in a fully fashioned jumper, the wearer creates the shoulder shape by deformation of the fabric.<br />
<br />
Not all knitted fabrics, nor garment types, respond to this approach and this chapter examines some of the principles of generating shape in the fully cut classes of knitted garments already outlined. The production methods applicable to the cutting stages will also be outlined.<br />
<br />
The process of cutting knitted fabric varies considerably depending on the particular branch of the industry. Practices range from the single garment handling of fully fashioned — where a cardigan front is slit or a V-neckline is cut out by hand on each garment individually, when the garment is already in an advanced state of make up — through to the enormous scale of cutting underwear from multiple lays.<br />
<br />
<b>Production</b><br />
<br />
Included in fully cut garments is a wide range of differing types of garment, including men's, women's and children's underwear, swimwear, sportswear and leisurewear. This range is generally regarded as within the scope of one type of company which differ largely in the definition of the market place in which they operate. A different sort of company is involved with the product range covered by the term jersey fabric.<br />
<br />
The companies producing the fully cut garment product range are usually characterised by being vertical in organisation. The company will knit its own fabric, often wet finish and dye it, cut, make-up and market the finished product. The specific product will decide the scale of operations and the organisation of production. At one end the making of men's or children's underwear is very much mass production, with a small variation in product design and size range. At the other extreme some leisurewear is now highly stylized and subject to the vagaries of fashion. The production is organised on small production runs, quick response, a large range of designs and multiple variations within a style.<br />
<br />
Jersey dresses, suits and other ladies outerwear garments are largely made by firms organized on a similar basis to firms making similar products in woven fabric. Some companies produce both jersey articles and the woven equivalent, although the cutting patterns are somewhat different and the making up techniques very different.<br />
<br />
The cutting process for fully cut knitted garments is largely the same as for woven garments. The garment itself is built up of two dimensional shaped portions of fabric, which are, after cutting, assembled by seams into a three dimensional shape to fit the human body. The shapes themselves are evolved from an interpretation of the design of the garment by a process known as pattern cutting. The pattern cutter is a highly skilled person who uses a mixture of geometry, experience and creative inspiration to arrive at the forms of individual pieces that make up a garment to look like the design. Often the pattern cutter and the designer is the same person.<br />
<br />
The pattern cutter may start with a 'basic block' which represents a simple interpretation of, say, an upper body outerwear garment and contains the correct sizing dimensions and a particular type of sleeve insertion. The geometry of the block is manipulated to generate details of shape, seam locations etc.<br />
<br />
Trials (toiles) of the garment are produced until the correct fit is obtained. The initial garment is of course only in one size, usually an intermediate size in the range that form the market for that particular garment.<br />
<br />
For example, in a normal womenswear size range the prototype would be designed in size 10 or 12. Other sizes would be generated by a process known as grading. This is another mixture of geometry and creativity, the object being to increase the sizes of each portion of the pattern while maintaining the general feel of the design on a variety of human body shapes. The pattern grader applies 'grade rules' that stretch or contract each portion of the pattern to a pre-determined formula.<br />
<br />
Such stretching or contraction is not uniform in all dimensions. A given increase in body width will not be accompanied by the same proportionate increase in length of sleeves. Important details like maintaining a fit between sleevehead and armhole require particular attention.<br />
<br />
This process of pattern making and grading results in a series of shaped pieces for each size of a particular style. Such shapes exist either as a series of strong cardboard or plastic cut-outs, or increasingly as shapes within a computer memory. It is from these shapes that a 'marker' is planned and a cutting order assembled.<br />
<br />
<b>The marker</b><br />
<br />
A marker portrays the way in which pieces of a garment are laid out on the fabric for cutting. The marker is laid out to a particular width of fabric and within an optimum length, and may represent only one size or a mixture of two or more sizes.<span class="Apple-tab-span" style="white-space: pre;"> </span><br />
<br />
<div>
<div>
The following factors are taken into account when planning the marker:</div>
<div>
<br /></div>
<div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>the width of the fabric from which the garments are to he cut;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>in knitted fabric, whether it is tubular, flat open width or folded on one side;</div>
<div>
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>the normal length of the lay, which is connected to the type and length of the cutting table;</div>
<div>
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span>the need to minimise the amount of waste between the marked out garment portions;</div>
<div>
(5)<span class="Apple-tab-span" style="white-space: pre;"> </span>the need to ease the path of the cutter blade without it getting into impossible corners;</div>
<div>
(6)<span class="Apple-tab-span" style="white-space: pre;"> </span>the need at all times to maintain the grain and directionality of the fabric;</div>
<div>
(7)<span class="Apple-tab-span" style="white-space: pre;"> </span>the alignment of patterns and checks etc.</div>
<div>
<br /></div>
<div>
Sometimes it is convenient to make a particular marker for a specific order, although it is more usual to standardize the marker/markers and vary the number of layers in the lays and the number of lays assembled.</div>
<div>
<br /></div>
<div>
The marker itself can be prepared in a number of different ways. At the most primitive the individual portions of the garments are represented by cardboard cut-outs. These are assembled on the top layer of fabric and the outline drawn round using a piece of tailors chalk. This method is very time consuming, requires a high level of skill and is open to errors through movement of the pieces and deformation of the fabric. The chalk needs to be kept sharp at all times to aid accuracy. This system is used for highly patterned fabrics that have to align within the garment, and also for short runs and prototype garments.</div>
<div>
<br /></div>
<div>
The hand marking system is advanced one stage further by being carried out on a sheet of paper duplicated by various methods to form repeats of the marker which can be laid on top of the fabric and cut along with it.</div>
<div>
<br /></div>
<div>
The marker maker lays out the pattern pieces on the paper according to a pre-determined plan. The width of the paper is the same as the fabric to be subsequently cut. The outline of the pattern pieces is drawn using a pencil or pen. To duplicate the marker several methods are available. The paper may be the top of several pieces interleaved with carbon paper, or it may be made of the type of paper that produces a line in response to localised pressure on its own surface. Carbon copies are of course limited due to the number of copies that can be obtained legibly from such a process.</div>
<div>
<br /></div>
<div>
In other processes the first marker is a master copy which is duplicated. Similar methods are used to those in office type duplicators, such as spirit duplicating, xerographic duplicating and pressure transfer. A form of photographic process using ultra-violet light sensitive paper has also been used. Clarity of line and accuracy are very important factors which, assessing these systems, as well as the cost factor. Increasingly computers are taking over the task of producing the master .copy of the marker, or are bypassing the processes completely with the aid of automatic cutters. </div>
</div>
<div>
<br />
<b>Marker making by computer</b><br />
<b><br /></b>
The past 15 years have seen a revolution in pattern making, grading and marker making in the form of computer systems. Such systems are produced by several manufacturers including Gerber, Investronica, Lectra and Cybrid.<br />
<br />
Early systems were characterized by their high initial cost, often out of reach of all but the largest manufacturers. In the past four years another revolution has taken place with the introduction of the first low cost system, Ormus, of the British company Concept II. This system also has the advantage of being, it is claimed, designer friendly, allowing a creative approach to pattern making. Gerber have responded to this challenge with their own low cost system, the Acumark 300, and Investronica with the lnvesmark DS. Such computer systems do much more than marker making. Lectra, for example, claim that their systems will perform the following tasks:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>digitising and storage of master patterns;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>independent input and storage of grade rules;<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>modification of master pattern via digitizer or colour graphic screen;<br />
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span>creation of new styles via digitizer or colour graphic screen;<br />
(5)<span class="Apple-tab-span" style="white-space: pre;"> </span>interactive logical lay planning;<br />
(6)<span class="Apple-tab-span" style="white-space: pre;"> </span>plotting and storage of markers;<br />
(7)<span class="Apple-tab-span" style="white-space: pre;"> </span>plotting of single or nested shapes;<br />
(8)<span class="Apple-tab-span" style="white-space: pre;"> </span>automatic lay planning;<br />
(9)<span class="Apple-tab-span" style="white-space: pre;"> </span>automatic digitizing and grading utilizing scanners;<br />
(10)<span class="Apple-tab-span" style="white-space: pre;"> </span>automatic laser cutting of card pattern;<br />
(11)<span class="Apple-tab-span" style="white-space: pre;"> </span>automatic knife cutting of multi-ply lays;<br />
(12)<span class="Apple-tab-span" style="white-space: pre;"> </span>automatic laser cutting of single-ply fabric.<br />
<br />
Such a list covers a range of several differently configured systems; not all systems are teamed with autocutters for example.<br />
<br />
Lectra's list could be matched in full or in part by the other principal manufacturers.<br />
<br />
Markers are produced using computer systems as follows:<br />
<br />
The garment portions themselves are established within the memory of the computer, either by creating them via the keyboard, digitizer and VDU screen, or by inputting existing pattern shapes using a full scale digitizer and reading off points around the pattern, or by scanning devices<br />
that 'read' the shape of pattern pieces placed on a special table. The latter system is the speciality of Cybrid Ltd.<br />
<br />
The garment. pieces can be graded within the computer system. Grade rules are provided by the system manufacturers but companies often prefer to use their own particular formulae. Markers can be planned within the computer systems via a display of a miniature length of the fabric on the VDU, and the placement of called-up, scaled portions of the garment on to it. Endless manipulation of the pieces is possible to achieve the most economical marker either by the operative or automatically by the computer working ceaselessly to achieve the best fit and to produce the minimum of waste.<br />
<br />
<b>Hardware and software</b><br />
<b><br /></b>
The minimum for a clothing computer system consists of the following items of computing equipment, interlinked and controlled by a series of software programs:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>The computer itself provides the facility to manipulate information input and provide rapid output. The computer also provides memory capacity to retain a certain amount of information placed into it or generated during its activities. Information can also be output in a transferable form, usually a floppy disc.<br />
<br />
Computers are classified according to their memory handling capacity and their speed of activity. Most of those used in clothing application are classed as micro or mini.<br />
<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>Inputs into the computer are of two sorts: keyboard symbols; or two dimensional special, e.g. digitizer or scanner. The keyboard is used to type in command functions and information in the form of words, numbers and symbols. It can also be used interactively to generate new software programmes or sub routines. The digitizer is an essential part of a graphic design system. It consists of a magnetic board which can sense the position of a pen or stylus and change that information instantly to co-ordinates that the computer can understand, locate and store.<br />
<br />
The same function can be carried out by a 'mouse' — a small box with control buttons and a small protruding window engraved with a cross. The mouse is held in the hand, glides easily over a smooth surface via a roller in its base and transmits the co-ordinate locations of the cross to the computer without the need for a digitizer board.<br />
<br />
Some systems, e.g. Ormus, combine the function of the keyboard with the digitizing pad so that most of the commands can be given without changing devices during working. Such a facility makes the system more user friendly and particularly designer friendly.<br />
<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>The interaction with the computer is displayed to the user stage by stage on VDUs (visual display units), otherwise known as monitors. These are television-like screens, monochrome (black and white) or colour. Most clothing systems use two monitors, one largely displaying commands and the other largely displaying graphical representations in miniature of the manipulated two dimensional shapes.<br />
<br /></div>
<div>
<div>
(4) The output device of a graphic clothing system is the 'plotter'. Individual pattern pieces, nests of graded pieces or full size markers are produced by a two dimensionally controlled pen tracing the outlines on a piece of paper whose movement is also controlled. Plotters fall into two</div>
<div>
categories:</div>
<div>
<br /></div>
<div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>flat bed plotters where the paper is on a large table and moves in one direction when required, with the pen moving in two dimensions over the whole surface of the paper;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>roller plotters where the paper is stretched over a roller and moves backwards and forwards over the roller, while the pen moves in one dimension only from side to side.</div>
<div>
<br /></div>
<div>
Plotting speeds can be very fast. Gerber plotters, for example, can draw at 2.3 m per second.</div>
</div>
<div>
<br /></div>
<div>
<div>
<i><b>Scanners</b></i></div>
<div>
<i><b><br /></b></i></div>
<div>
Some systems employ large scanners to imput patterns or block patterns into the computer system. A British firm, Cybrid, specialises in such systems, arguing that digitizing a series of existing pattern pieces is unnecessary and time wasting.</div>
<div>
<br /></div>
<div>
Their scanner is a box-like table 1 m x 1.7 m. On to this up to 15 pattern pieces can be laid, forming the basis of a lay plan. The individual pieces are aligned along the length of the box, as with the fabric grain. More than one arrangement of pieces can be scanned if the lay consists of more than 15 pieces or if the scanner table cannot accommodate the size of the pieces.</div>
<div>
<br /></div>
<div>
When the pieces have been arranged on the scanner bed, the lid is lowered and the pieces scanned optically/electronically so that they appear within a computer memory and can be displayed on a VDU screen. The individual pieces can then be reproduced in mirror image or multiplied.</div>
<div>
<br /></div>
<div>
Lay planning is now carried out automatically by the Cybrid computer, which is capable of working away, literally overnight, generating 'best fit' solutions that can be 'dumped' on to a disc and printed out on a miniature plotter for consideration before marker making on a full size plotter is carried out. Such a system has distinct appeal to firms that start with a stored pattern in full size on paper card.</div>
<div>
<br /></div>
<div>
Fig. 3.2 gives a summary of the possible outputs and inputs of a design/manufacture computer as used in the clothing industry. Not all the items listed are necessarily used on the same system.</div>
<div>
<br /></div>
<div>
<b>Spreading</b></div>
<div>
<br /></div>
<div>
The scale of production of fully cut knitted garments is such that, with one or two 'exclusive' exceptions, cutting is carried out on multiple layers of fabric. To arrive at a 'lay' a process of spreading is carried out.</div>
</div>
<div>
<br /></div>
<div>
<div>
Spreading a lay of knitted fabric involves similar technology to that of woven fabric spreading, with one large exception. Knitted fabric is extensible and is readily distorted in width and length. Great care must be exercised in handling the fabric at all stages, whether the spreading is carried out manually or by machine. The fabric must finish on the table in as relaxed a state as possible.</div>
<div>
<br /></div>
<div>
Knitted fabric before spreading may itself be deformed and thus have potential shrinkage. This is a particular problem with fabrics knitted from cotton and usually manifests itself in high shrinkage by length (along the wale) in garments after their first washing. These fabrics have in fact been distorted during dyeing and finishing and have not found it possible to relax with time, or to relax in the roll form in which most knitted fabric is presented. Very stringent quality control procedures are required both to sample fabric prior to spreading and to assess degrees of distortion during spreading.</div>
</div>
<div>
<br /></div>
<div>
<div>
<b>The Starfish project</b></div>
<div>
<b><br /></b></div>
<div>
The International Institute for Cotton in 1984 introduced to the industry the results of an extensive research programme into the shrinkage of knitted cotton fabrics that has 'led to a practical system for reliably predicting the shrinkage and dimensional properties of finished knitted cotton fabrics'.</div>
<div>
<br /></div>
<div>
This research project was given the code-name Starfish. In this research the establishment of a stable state (i.e. fully relaxed and reproducible) was extremely important. This stable state was called reference state and was achieved on all the samples by the following procedure:</div>
<div>
<br /></div>
<div>
<ol style="text-align: left;">
<li>wash in automatic machine at 60°C;</li>
<li>tumble dry to constant weight;</li>
<li>wet Out in a washing machine (rinse cycle);</li>
<li>tumble dry to constant weight;</li>
<li>repeat steps 3 and 4 three more times, making a total of five cycles; </li>
<li>condition to normal regain, i.e. allow the sample to adapt to its normal moisture content in a standard atmosphere.</li>
</ol>
</div>
<div>
Further work showed that distortion of fabrics occurred during wet finishing and subsequent drying, and that differing treatments resulted in different reference states. Factors that need to be controlled during the knitting process are loop length and yarn count. In finishing, the beneficial effects of tumble drying or pseudo tumble drying, where the fabric is maintained in a state of unstressed agitation during the drying cycle, are noted.</div>
<div>
<br /></div>
<div>
Finally, the model relates the fabric finished state to the performance of the garment during wear and subsequent to laundering processes.</div>
<div>
<br /></div>
<div>
The package is marketed as a computer program and a hand held slide rule calculator. These arc prescriptive and predictive, forming valuable tools for all manufacturers of fully cut knitted goods made from cotton fibres.</div>
<div>
<br /></div>
<div>
<b>Hand spreading</b></div>
<div>
<b><br /></b></div>
<div>
Spreading can be effected by hand or machine. Cutting tables for knitted fabrics must be particularly wide. Slit fabric from 30 in diameter knitting machines can commonly be 90 in (2.28 m) wide and this is by no means the largest diameter. Hand spreading requires at least two people standing on opposite sides of the table. They not only unroll the fabric but constantly vibrate or shake the fabric to position it. Any localised pulling will distort the fabric which will he prevented from recovery by friction with the adjacent layers. Inevitably with knitted fabric the edges of the fabric within the lay are less well aligned than with lays of woven fabric, and there is greater edge cutting loss. The overall width and length of the lay must also be constantly checked, as distortions of dimensions tend to be cumulative and once induced may affect every layer and be very difficult to eliminate once the lay is built up. As already mentioned, knitted fabric is often processed in circular form or in slit/folded form. Both these of their own handling problems in maintaining the alignment of the two layers.<br />
<br /></div>
</div>
<div>
Most knitted fabric is uni-directional — there is a definite top and bottom to the fabric. (Only plain fabric of the simplest type can be treated as hi-directional.) Fabric that is uni-directional must have each layer of the lay going in the same direction; fabric must be processed from the same end of the cutting table for every layer. For plain fabric that is bi-directional, building the layers can take place from each end of the table alternately. This is of particular advantage when spreading with automatic or semi-automatic machinery.<br />
<br />
Knitted fabric is usually different in appearance front to back, with one of the surfaces being selected to he the effect side. With fabric finished in tubular or folded form within the lay, fabric can be positioned effect side up or reverse side up. This can also occur with spreading by machine where the uppermost side changes according to which end each traverse is made from.<br />
<br />
This is relatively unimportant with most of the common garment portions that are either width symmetrical in themselves or occur in mirror image form, left and right. But where garments are constructed asymmetrically the fabric must be the same side up in the lay and of open width finish. Such garments are, however, extremely rare.<br />
<br />
Knitted fabric can be patterned either in colour or structurally. Stripes, prints and knitted colour designs present alignment problems both in terms of the layers of fabric within the lay and in terms of the marker in relation to the lay. Inevitably extra care must be taken and a high degree of handling skills are required to spread such a lay.<br />
<br />
Increasingly printed pattern alignment is ignored in leisure garments and underwear, much to the relief of production managers. There is also increasing use of printing processes applied to finished garments.<br />
<br />
<b>Machine spreading</b><br />
<br />
A spreading machine consists basically of a frame that bridges the table on which the lay is to be formed. The frame, mounted on rollers, supports and carries the fabric in roll or folded form, and the fabric is delivered as the frame passes along the length of the table (Fig. 3.3). Spreading machines vary considerably in their size and complexity ranging from simple hand-manipulated machines that contain one roll of fabric and are trundled by hand backwards and forwards along the length of the lay, to large, fully automatic, programmed machines that change rolls from a magazine and produce the correct sequence and number of different colours or fabrics in the lay (Fig. 3.4). There is a bewildering array of machines in between these extremes, with individual firms producing their own specification for machines to be made for them.<br />
<br /></div>
<div>
<div>
The machines vary in their manner of traversing the length of the table. In the simplest system the .frame, or carriage, is mounted on wheels that fit on to rails on either side of the table. As the machines advance in complexity and automation the wheels become driven, or become gear engaging with a rack replacing the rail. Location of the carriage relative to the length of the table becomes important, as also does delivery of the fabric with the machine positively driving the roll either on its surface or axially.</div>
<div>
<br /></div>
<div>
With all machine spreading it is impossible to remove the human element required to supervise the machine. Human tasks involve dealing with observed fabric faults, with rolls of fabric that run out in the middle of the lay, and, with knitted fabric in particular, undesirable stretching and skewing of the fabric.</div>
<div>
<br /></div>
<div>
All knitted fabrics need to be spread with the minimum of applied tension, and while machine makers claim that all their machines do this, there are some specialist machines particularly designed to handle knitted fabrics. CRA (Cutting Room Appliances Corporation) are one manufacturer of these. Their Systema series offers the ability to handle widths up to 3 m (120 in) with a load capacity of 182 kg (400 lb) on the roll. Synchronized feed rollers work in conjunction with the self adjusting dividers to compensate automatically for variations in the tension and width of the fabric. One version of the machine will handle folded fabric (cuttled or flopped).</div>
<div>
<br /></div>
<div>
<b>Spirality</b></div>
<div>
<b><br /></b></div>
<div>
There is at least one other fabric distortion besides stretching, that occurs in knitted fabric and results in spreading difficulties. `Spirality' arises from twist stress in the constituent yarns of plain fabric, causing all loops to distort and throwing the fabric wales and courses into an angular relationship other than 90°. If the fabric is retained as a tube, the spirality throws the vertical alignment of the fabric awry so that the wales lie at an angle to the edges of the fabric and slowly spiral around the fabric. Garment portions cut from the fabric show obvious distortion and are worthless (Fig. 3.5).</div>
<div>
<br /></div>
<div>
If the fabric is slit along a wale line during the knitting process or immediately prior to finishing, the distortion still takes place but appears as a course distortion, with the courses lying at an angle to the cut edges of the fabric. Fabrics with this problem often appear in low cost underwear and tee shirts, angled courses appearing to the consumer to be much less of a fault than angled wales.</div>
<div>
<br /></div>
<div>
Plain knitted fabrics made from single cotton yarn are most prone to spirality, the degree being related to the number of twists/unit length in the yarn. Such yarn is said to be 'twist lively' and, unlike similarly constructed yarns produced from thermoplastic fibres, cannot be heat set in yarn or fabric form to eliminate spirality.</div>
<div>
<br /></div>
<div>
Spirality is measured by the number of degrees of distortion that the fabric is away from a 90° relationship of wale to course. Fabrics of around 10° spirality are commonly processed, although acceptability varies with the quality, price bracket, and end use of the particular goods.</div>
</div>
<div>
<br /></div>
<div>
<div>
Resin treatment known as cross linking is sometimes used to reduce the degree of distortion due to spirality. The resin is applied to the fabric in aqueous solution and is set by passing the fabric once through a high temperature stenter (see Glossary). Besides eliminating some or all of the spirality, improved dimensional stability, appearance and handle are claimed for the process. Its main drawback is a general weakening of the cotton fabric.</div>
<div>
<br /></div>
<div>
Spirality is minimised by the use of doubled (two-fold) yarns, but this pushes up the price prohibitively in all but the most expensive garments.</div>
<div>
<br /></div>
<div>
Spirality does not occur in 1 x 1 rib and interlock fabrics, the loops formed in opposite directions cancelling out the distortions.</div>
<div>
<br /></div>
<div>
Another mild form of spirality occurs in fabrics produced on multi-feeder circular machines, because the number of courses knitted in one revolution of the machine distorts the wale/course relationship (Fig. 3.6). For example, a 30 in diameter machine with 90 feeders of 20 gauge will knit approximately 3 in of fabric every revolution. This will produce, if the fabric is finished 90 open width, 2° of spirality.</div>
<div>
<br /></div>
<div>
Usually open width finishing with the fabric passing through a stenter will correct this. Finishing the fabric in tubular form will not.</div>
</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-2270277788408593292017-01-27T01:57:00.002-08:002017-03-01T03:24:34.632-08:00Weft Knitted Fabrics<div dir="ltr" style="text-align: left;" trbidi="on">
It is not possible to discuss the technology of knitted garment manufacture without describing the constituent fabrics that influence the construction and properties of garments made from them. At the same time it must be stated that this is not intended to be a comprehensive treatise on knitted fabric.<br />
<br />
<b>Looped fabrics</b><br />
<br />
There are three recognised looped constructions: warp knitting, weft knitting and crochet (Fig. 2.1).<br />
Warp knitting is characterised by the structural threads of the fabric running along the length of the fabric approximately parallel with the selvedge. One horizontal row of loops, or course, is made from many threads.<br />
<br />
Weft knitted fabrics are characterised by the structural threads being perpendicular to the selvedge of the fabric. One horizontal row of loops (course) is made from one or very few threads.<br />
<br />
Crochet, unlike the other two constructions, is solely hand-made. One thread is used which chains upon itself, and cross links are formed with previously formed chain to generate fabric.<br />
This book is solely concerned with weft knitting.<br />
<br />
<b>Weft knitting</b><br />
<br />
Knitted fabrics are formed from loops. The constituent loop of weft knitting is of the general shape shown in Fig. 2.2. It is said to have length (€), i.e. the length of the thread forming it from a to b. This is its most important dimension and in fact decides the area the loop covers and its width and height within a construction.<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-0bOGKwhhqn0qz8QT-n-IV1rqao3K-5Mq6ue9pwmVJvharR9NwJ2hWSQzVey4uvd2frPwyeBROf-sltAzTjFCD7GXaBxxkA4aIQUcNyg_g6aYJ__dHQ9E3purDVCIFKwgIRUb4y_Lpxk/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-0bOGKwhhqn0qz8QT-n-IV1rqao3K-5Mq6ue9pwmVJvharR9NwJ2hWSQzVey4uvd2frPwyeBROf-sltAzTjFCD7GXaBxxkA4aIQUcNyg_g6aYJ__dHQ9E3purDVCIFKwgIRUb4y_Lpxk/s1600/Untitled.jpg" /></a></div>
<br />
<div>
<br />
The loop in fact consists of two bends, an upper one and a lower one, half of which is on either side of the overall construction. The loop can vary in size, that is its length (€) can alter. It is rather obvious that as the loop length increases the area the loop occupies gets larger. Such a relationship is independent of the diameter of the constituent yarn, although usually within a knitted construction the yarn size increases commensurate with the loop size (Fig. 2.3).<br />
<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcN_Ds54V_3wtjRH7xHF376RrL1wmq0UZU1CXtGqx1A4uk6bxGA2Va3a3MU_eBR4Tt-ppysFxacHlXnMdoL3R6Vo_-7MzehoJK_MUymZqIsxncEPDcM4oi756pctfdIgv1uPis1y_0P-A/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcN_Ds54V_3wtjRH7xHF376RrL1wmq0UZU1CXtGqx1A4uk6bxGA2Va3a3MU_eBR4Tt-ppysFxacHlXnMdoL3R6Vo_-7MzehoJK_MUymZqIsxncEPDcM4oi756pctfdIgv1uPis1y_0P-A/s1600/Untitled.jpg" /></a></div>
<br />
We can describe such loops by relating them to familiar articles, so that the small loop represents the constituent part of a ladies hose or tights fabric, (loop length 0.2 cm), the medium loop the constituent part of a ladies fully fashioned classic sweater (loop length 0.55 cm) and the coarse loop a man's heavy outerwear sweater (loop length 3 cm).<br />
<br />
Loops can be related to one another and can be intermeshed with one another to form fabrics. In a horizontal direction the relationship is a simple one of a series of loops formed by the same thread diagram (Fig. 2.4). In the vertical direction loops can be joined together by intermeshing (Fig. 2.5), whereby individual loops are connected by drawing subsequent loops through previously formed loops. The result is a fabric of matrix-like construction, having vertical and horizontal series of loops (Fig. 2.6).<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhc5kVoJME2KZi7n_lbhRg7BvC8ROlpFm4DsWZjO8lt8ljsu3ugFA4oX2KujEDYS7nCJDG_JO6GfV2qMzGrtpMdYqn8anGbPp8i5u2VSIoZttly4orXRLJ0LWJHfrLanZhwnSi3smOw6Qg/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhc5kVoJME2KZi7n_lbhRg7BvC8ROlpFm4DsWZjO8lt8ljsu3ugFA4oX2KujEDYS7nCJDG_JO6GfV2qMzGrtpMdYqn8anGbPp8i5u2VSIoZttly4orXRLJ0LWJHfrLanZhwnSi3smOw6Qg/s1600/Untitled.jpg" /></a></div>
<br />
<i>Course </i>A horizontal row of loops is known as a course.<br />
<i>Wale </i>A vertical row of loops is known as a wale.<br />
<br />
<b>Plain fabric</b><br />
In the simplest fabric construction all the units are of the same sort, i.e. each loop is the same shape and is pulled through the previously knitted loop in the same manner or direction. This simplest fabric is called plain weft knitted fabric, usually abbreviated to plain fabric (Fig. 2.7). Because all the loops intermesh in the same direction the fabric has a different appearance on each side. The side to which the loops appear pulled through is known as the 'face' or 'technical face'. The side from which the loops appear pushed away is known as the 'back' or 'technical back'.<br />
<br />
Another characteristic of constructional appearance is that it is impossible to differentiate between the top of the fabric and the bottom.<br />
<div class="separator" style="clear: both; text-align: center;">
<img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjr4Q465S804b1NNuU11AwD7R5qFVRxyXxjpXkIURDZPYGpwK78kzS1jcdEghgbLvaO6T7sLBXcOr4bm6tR3Gia4Rq1Znpns7-qj4CJqTCaAERJupWFKH8rQiMHvGgWSQ3w_0rB08RNCmE/s1600/Untitled.jpg" /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEilcswEkM8MajCvnR7PyOEnT5TErqcpzoiDltixDHoowWugE7v3Iivkd_1bxkXK6Eo-UtPe_Ok7wxrfW6bIWNShM0RLO9xM8Sd1VxQpVnIytSP-4tr0ymTEyynHQL9TPEbJHKGr9NHNEJs/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEilcswEkM8MajCvnR7PyOEnT5TErqcpzoiDltixDHoowWugE7v3Iivkd_1bxkXK6Eo-UtPe_Ok7wxrfW6bIWNShM0RLO9xM8Sd1VxQpVnIytSP-4tr0ymTEyynHQL9TPEbJHKGr9NHNEJs/s1600/Untitled.jpg" /></a></div>
<div class="separator" style="clear: both; text-align: center;">
<br /></div>
<br />
<b>Properties</b><br />
<b><br /></b>
The fabric is extensible in a course-wise direction and in a wale-wise direction. However, the degree of extensibility is different when pulled top to bottom from when pulled side to side. The course-wise extension is approximately twice that of the wale-wise extension due to the degree of constraint imposed on each loop by ifs intermeshing.<br />
<br />
The loop pulled vertically extends by half its length<span class="Apple-tab-span" style="white-space: pre;"> </span>while the loop pulled horizontally extends by its whole length, € (Fig. 2.8). The degree of recovery from stretch is not a property of the construction but depends on the nature of the raw material and yarn construction.<br />
<br />
This is the first of the properties related to the Hsu-al and historical use of the fabric; garments made from plain fabric are constructed so that the minimum stretch is placed vertically on the human body and arms, and maximum stretch around the body. Present and past fashions usually demand garments that do not sag readily. Periodically there have been exceptions to this usage where the wales of the fabric have run from side to side of the garment. The Dolman sweater of the 1950s and more recently is one such usage.<br />
<br />
The Dolman fashion was essentially draped, with folds developing under. the arms and around the tightly constrained waist. The draping was aided by another differential property of plain fabric: that the ease of bending the fabric is dependent on which side the bend is occurring, and whether the bend is wale wise or course wise (Fig. 2.9).<br />
<br />
On the face of the fabric, bending takes place most readily along the wale outwards. On the back of the fabric bending takes place more readily along the course outwards. These subtleties of mechanical performance are very important in dictating the overall appearance of a garment. In a piece of unprocessed, unpressed plain fabric, the outer edges curl vigorously. The top and bottom curl in towards the face of the fabric and the sides towards the back of the fabric. Curling towards the face tends to diminish the forces causing the curling at the sides; likewise curling towards the back diminishes the tendency to curl towards the face. A few seconds play with a piece of fabric will show this to be true. In fact in the literal sense the fabric can be said to be most in a state of equilibrium when it is in a roll or sausage form.<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEic2GIl36_-n9xV4-flB76TxOvoIzgesSOrtwP9doYab7o2fsUFPLxU8wNz-AFEUKAyJxGHBauB1v-SNr4bNWaF-YeJfKpRhz6WOKF5xz5DDtN0eRvY1yGtAiQOUbf99ropP3AoE4x2kVs/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEic2GIl36_-n9xV4-flB76TxOvoIzgesSOrtwP9doYab7o2fsUFPLxU8wNz-AFEUKAyJxGHBauB1v-SNr4bNWaF-YeJfKpRhz6WOKF5xz5DDtN0eRvY1yGtAiQOUbf99ropP3AoE4x2kVs/s1600/Untitled.jpg" /></a></div>
<br />
<div>
<div>
Pressing or other heat/water processes are used to minimize or eliminate such curling which is caused by the directionality of the loop . formation. A cross section of the fabric cut vertically between wales (Fig. 2.10) shows that each loop bends in the same direction, towards the face, and is constrained in that form by being intermeshed with the loop below. However, the loop at the top is not constrained and is free to straighten, releasing the next loop, and so on, the guiding principle being that no loop or portion of yarn wishes to remain strained by bending.</div>
<div>
<br /></div>
<div>
A cross section through the fabric along the course (Fig. 2.11) shows a similar situation, all loops being curved towards the back. Again a release of the bending forces on the loops results in them straightening and curling towards the back of the fabric.</div>
<div>
<br /></div>
<div>
This property has a major influence on the design and construction of garments made from plain fabric. Obviously all the edges must be constrained in some way unless curling is deliberately desired. This is achieved by seams, welts and the use of other fabrics of a more stable</div>
<div>
nature, especially ribs.</div>
<div>
<br /></div>
<div>
In addition, almost all garments made from plain fabric are constructed with the face outwards as the 'effect side', with the back inwards as the `reverse side'. This is primarily because of the difficulties of constructing side seams from pieces of unprocessed fabric. It is much more difficult to uncurl the edges of fabric when they are trapped between two layers, than when they are on the outside (Fig. 2.12). Neatness of appearance also plays a part in this choice.</div>
</div>
<div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjooudW6pysoWW75BE0XW_OruibRvm7sbUsJe8dlAi4oux8EYFJnSqHZf1lrRa6fjnzcSqOYARgD261qMsK4LkwkfsARJVlAZ2M_t6pfeXTrPvrv8_dmmbZo9QqNqQFv3ENm73b_lLwQyI/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjooudW6pysoWW75BE0XW_OruibRvm7sbUsJe8dlAi4oux8EYFJnSqHZf1lrRa6fjnzcSqOYARgD261qMsK4LkwkfsARJVlAZ2M_t6pfeXTrPvrv8_dmmbZo9QqNqQFv3ENm73b_lLwQyI/s1600/Untitled.jpg" /></a></div>
<br /></div>
<div>
<div>
The constituent loops of plain fabric can readily be disconnected from the structure, course by course, by merely pulling at the most exposed thread. This can take place either from the end first knitted or the end last knitted and is known as unroving. A related disconnection of loops leading to a breakdown of the structure is caused by a series of loops being sequentially unmeshed down one or a group of wales. The resulting fault is known as a ladder. Plain fabric incorporated into garments must be firmly locked into seams, or the structure changed into a different non/laddering, non/unroving form, such as the rib of a waistband or cuff of a sweater.</div>
<div>
<br /></div>
<div>
All knitted fabrics, including plain fabric, are relatively thick compared to the diameter of their constituent yarns, and are composed largely of air space. Because of this, knitted fabrics have excellent heat insulating properties. However their openness leads them to being very air/ water permeable, and therefore neither waterproof nor heat retentive under conditions involving air movement.</div>
</div>
<div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjM-8nDcN-Czylj4cH5Cn_wx0KBWM12MaL8nMqvfB_fKTTxUR4wW04xTplmiAjW_3SSE9nTiUmN4-654ZzUjJYq1bfc7gUOQYQ7etqB9VwzKtC14tlySFCixW7ld3amJqY_6_UjhOtgWRQ/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjM-8nDcN-Czylj4cH5Cn_wx0KBWM12MaL8nMqvfB_fKTTxUR4wW04xTplmiAjW_3SSE9nTiUmN4-654ZzUjJYq1bfc7gUOQYQ7etqB9VwzKtC14tlySFCixW7ld3amJqY_6_UjhOtgWRQ/s1600/Untitled.jpg" /></a></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhcloRT6R38ptzF8l6QFTWzI7IYzIl4gVMTuIeDcdd1OcEvSSBfv3HbBmaez9I4Q91bv6SbCDA3nsMYneJ5khnOatE9OWxzwzwYiY0aM5unbdJkSsKU2vDF51kRZs9kiscHOwaHHdv_CMw/s1600/Untitled.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" height="372" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhcloRT6R38ptzF8l6QFTWzI7IYzIl4gVMTuIeDcdd1OcEvSSBfv3HbBmaez9I4Q91bv6SbCDA3nsMYneJ5khnOatE9OWxzwzwYiY0aM5unbdJkSsKU2vDF51kRZs9kiscHOwaHHdv_CMw/s640/Untitled.jpg" width="640" /></a></div>
</div>
<div>
<div>
Plain fabric is the commonest weft knitted fabric and is produced by widely different sorts of knitting machinery in all forms from circular fabric piece goods to fully fashioned panels. Other structures are covered here using the same terms and concepts as in the discussion of plain</div>
<div>
fabric.</div>
<div>
<br /></div>
<div>
<b>Rib fabrics</b></div>
<div>
<b><br /></b></div>
<div>
Rib fabrics are composed of loops formed in opposite directions, so when viewed from one side both hack and face loops are apparent. All the loops of any one wale are of the same sort, either hack or face. The name rib is derived from the ribs of animals, whose contours rib fabrics resemble.</div>
<div>
<br /></div>
<div>
The simplest rib fabric is the 1 x 1 (one by one or one and one). This is formed by alternating wales of back and face loops. (Fig. 2.13a) is purely schematic and does not show the fabric in its normal relaxed form. When the fabric is relaxed (Fig. 2.13b) and under no strain in the direction of the courses, it collapses to a situation of alternate wales touching one another. The wales in between are hidden but show on the opposite side of the fabric.</div>
<div>
<br /></div>
<div>
The fabric therefore looks the same on both sides and appears to casual viewing to be composed solely of face loops. This collapse of the fabric is caused by the portion of the loops that bridges the face loops and the back loops within the structure. When the fabric is placed under strain by stretching along the course, the bridging portions are twisted into an S form by the legs of the loops. This twisting forms a storage of energy and the structure acts like a spring, quickly regaining its collapsed form when the strain is released.</div>
<div>
<br /></div>
<div>
Because of this, rib fabrics are used where portions of garments are expected to cling to the shape of the human form and yet be capable of stretching when required. Waistbands, cuffs and collars are typical applications, together with whole garments of a fitting nature.<br />
<br /></div>
<div>
Extensions of up to 120% can be obtained along the course, with normal constructions. Along the wale, rib fabric behaves very much like plain fabric, with very limited extensibility. As already mentioned, the fabric has no back or front, the appearance being similar on both sides. The fabric is also stable as a plane structure with no tendency to curl.<br />
<br /></div>
<div>
Other constructions of rib are possible and are widely used, such as two wales of face loops alternating with two wales of back loops to form</div>
<div>
2 x 2 rib (Fig. 2.14). On the same basis there are 3 x 3, 2 x 1, 3 x 2 etc.<br />
<br /></div>
<div>
As the number of wales in each rib increases, the elasticity decreases </div>
<div>
because the number of change overs from back to front diminishes. Over</div>
<div>
3 x 3 rib the fabric more and more behaves like plain fabric, even curling in favour of the dominant rib. Such structures are known as 'broad ribs' (Fig. 2.15).<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgL8a7ZCdINxZZFJOGWlf6VKysVsoQeA0kSRhMYQEnXk06R4LMzv5xKeVQ6B0AzZr694s38BtNxqgs_PAgoYMHKOO_AHe74i6-4RiibFeBBCK_WR0ASTwKVxSsxzFGTalx6MJnrezFuSzk/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgL8a7ZCdINxZZFJOGWlf6VKysVsoQeA0kSRhMYQEnXk06R4LMzv5xKeVQ6B0AzZr694s38BtNxqgs_PAgoYMHKOO_AHe74i6-4RiibFeBBCK_WR0ASTwKVxSsxzFGTalx6MJnrezFuSzk/s1600/Untitled.jpg" /></a></div>
<br />
Rib fabrics will only unrove from the end last knitted and l x 1 rib will only ladder from the end last knitted (Fig. 2. 16). All other rib constructions will ladder from the end first knitted. Such a property reinforces the argument for using ribs on the extremities of garments.<br />
<br />
<b>Purl fabrics</b><br />
The simplest type of purl fabric consists of courses of face loops alternating with courses of back loops. This is known as 1 x l purl (Fig. 2.17). This, like 1 x 1 rib fabric, is balanced: for every face loop there is a back loop generating equal and opposite forces. The fabric is stable with no tendency to curl. It does, however, have a relaxed and extended form, collapsing in a vertical dimension so that each course lies at an angle to the plane of the fabric. Looked at from the side, the fabric, and indeed each wale, appears like a concertina. The fabric therefore has a large vertical extensibility which is largely elastic, depending on the fibre used and the yarn construction. The fabric is very bulky and has excellent thermal insulation properties.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzanwy2pBvLsEJc2fRtSlQ23bLlN2hAoE851LUS5yoFJSHhDIJPkM5WBWq-RL1IR1xLHyQ6dAKlYDD4RBkPuMV-_yMIpXx7uYTQ6z68eDh00DJwvPBmLHNbsypWMz8Y_C9qaxP7EtlhQE/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhzanwy2pBvLsEJc2fRtSlQ23bLlN2hAoE851LUS5yoFJSHhDIJPkM5WBWq-RL1IR1xLHyQ6dAKlYDD4RBkPuMV-_yMIpXx7uYTQ6z68eDh00DJwvPBmLHNbsypWMz8Y_C9qaxP7EtlhQE/s1600/Untitled.jpg" /></a></div>
<br />
<br /></div>
</div>
<div>
As with rib fabrics there are other combinations of simple purls, such as 2 x 2, 3 x 3 etc. These are uncommon, however, and not particularly useful.<br />
<br />
Unlike the rib fabric however, the classification 'purl' covers any fabric with face and back loops in the same wale. This covers a vast range of fabrics with designs in back and face loops, known as 'fancy purls'. Another term used, particularly in the USA is 'links-links'.<br />
<br />
The three classifications discussed in this chapter — plain, rib and purl — are absolute ones and all weft knitted fabrics can be categorised into one of these classes. To summarise:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>Plain — all the loops in the fabric are of the same sort, face or back, depending on which side is looked at.<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>Rib --the loops are of two sorts, face and back, but in any wale all the loops are of the same sort.<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>Purl — some if not all the wales contain loops of both sorts, front and back.<br />
<br />
It is of course possible to manipulate, modify and displace the loops in a fabric, but this does not alter the basis of the above classification.<br />
<br />
Within the classification it is possible to modify the structures by various means. It is also possible to introduce design into a fabric without changing the structure, by such means as yarn type, colour, lustre etc., or by striping and plating (see Glossary). Some structures can be described as hybrids with, in particular, combinations of rib and plain to form milano ribs or ripple (bourelet) fabrics.<br />
<br />
Others are unique structures like interlock and eightlock which fall into the rib category. Interlock consists of two 1 x 1 rib fabrics knitted in so that they are locked together. Eightlock is similar in construction but involves 2 x 2 rib. Interlock fabric is extremely stable; knitted in soft cotton yarns it is widely used in men's underwear, and leisurewear.<br />
<br />
The main modifications used to alter knitted structures fall into three categories: tuck stitches, miss stitches, and transferred and displaced loops. It is not the purpose of this book to be a knitted fabric manual, but brief descriptions of these three categories are given here with mention of their significance in garment construction.<br />
<br />
<b>Tuck stitches</b><br />
<b><br /></b>
A tuck loop is a loop that is incorporated into a knitted structure without actually passing through or intermeshing with the loop immediately below it, but is intermeshed with the succeeding loop. Because the tuck loop is missing from the structure, the loop below it is stretched slightly to bridge the gaps. This loop is known as the held loop (Fig. 2.18). When a series of tuck loops are formed one after another in one wale, the structure distorts and a `knop' occurs (Fig. 2.19). When a series of tuck loops are formed adjacent to one another in a course, they form a float on the back of the fabric (Fig. 2.20).</div>
</div>
<div>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi6VHBOfCD9lRa8KGvUCjWs_e2QWVyZVrVHziV1kMyRyYkwAGFBChkBFRRpG7sR8fl6-Kn2894zbmS-cT6Qq-Zr9t5Hu_dELpfs_VoFWYiuSKUypR9xWsy8TBSku-9Wd30OeG2d5ZDA5jc/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi6VHBOfCD9lRa8KGvUCjWs_e2QWVyZVrVHziV1kMyRyYkwAGFBChkBFRRpG7sR8fl6-Kn2894zbmS-cT6Qq-Zr9t5Hu_dELpfs_VoFWYiuSKUypR9xWsy8TBSku-9Wd30OeG2d5ZDA5jc/s1600/Untitled.jpg" /></a></div>
<br />
<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg06d6-RfZpyu_3TZ_1W4p5XUBHgUHW6r4hCK0PVskjke4ibdAgIG8RyvxK4_CpOprcZFJf9klIlFQ1yUXhr1sXKlkOCFbdja5QOSRuOpNsUoChukr4hU7MHjekoGQN5alSrAOvLrTviIE/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg06d6-RfZpyu_3TZ_1W4p5XUBHgUHW6r4hCK0PVskjke4ibdAgIG8RyvxK4_CpOprcZFJf9klIlFQ1yUXhr1sXKlkOCFbdja5QOSRuOpNsUoChukr4hU7MHjekoGQN5alSrAOvLrTviIE/s1600/Untitled.jpg" /></a></div>
</div>
<div>
<div>
<br />
One of the most interesting consequences of incorporating tuck loops into a knitted structure of any classification is the widening of that fabric. The more tuck loops the more the fabric widens relative to a similar structure containing no tuck loops. This is caused by the sides of the tuck loop, which would normally be constrained by the previously knitted loop, straightening out and exerting outward pressure on the neighbouring loops. The widening effect can be used in garments to 'stitch-shape' portions of the garment where extra width is required.</div>
<div>
<br /></div>
<div>
Common constructions include 1 x 1 cross tuck in plain fabric with its variations, and half and full cardigan in 1 x 1 rib fabric. Tucking can also be a colour pattern method, particularly in plain fabric fully fashioned outerwear. The colour patterning is based on the premise that tuck loops side by side in a course generate a float which is not seen on the face side of the fabric.</div>
<div>
<br /></div>
<div>
<b>Miss stitches</b></div>
<div>
<b><br /></b></div>
<div>
A miss loop is generated when a loop is missed out of a knitted structure altogether, and does not pass through the loop below nor intermesh with the subsequent loop. The yarn that would have formed the loop lies as a float across the back of plain fabric (Fig. 2.21). As in the tuck stitch, the loop that stretches across the gap is known as the held loop.</div>
<div>
<br /></div>
<div>
Miss stitches can be used for generating structural interest as floats on the technical back of plain fabric, or as held stitch designs on the face, or to create 'relief' effects on rib fabrics. Their main use, however, is as the colour patterning medium of knitted fabrics, both plain and rib. In the simplest situation two threads form complementary loops; where one knits the other misses, and vice versa (Fig. 2.22).</div>
<div>
<br /></div>
<div>
More complex variations of this simple structure are used to generate rib jacquards, in which one side of the fabric contains the pattern, and the other — the reverse side — has various structures to create balance or imbalance with the face. Some of the structures can be so imbalanced (i.e. more loops on one side than the other) as to cause the surface of the fabric to bubble within a pattern. Such fabrics are known as 'relief'.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgMjnEk0zfRKdSjhOVDv5j652LkIRIgvNeGQK8doQJnltoNU8V9WIz_xbUXjerKdYrxxvEokJenzRo020-zsdGcXQn-WuapRybJR3zMaLlUb-UClmO0M2n7TSQN5cHY3Bll64XP_Fjr94M/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgMjnEk0zfRKdSjhOVDv5j652LkIRIgvNeGQK8doQJnltoNU8V9WIz_xbUXjerKdYrxxvEokJenzRo020-zsdGcXQn-WuapRybJR3zMaLlUb-UClmO0M2n7TSQN5cHY3Bll64XP_Fjr94M/s1600/Untitled.jpg" /></a></div>
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh1Ho0vMUY9LsG619QJQJ9hcGJ_Y3yYSm3UM8Mn1yx6UKMKd28LdbT2CM-rsB5A_RsM1505bw79EeIjLFyGhN8-41lDDMHGOapR_tZgqvLGJId3TpOq67tBBKNEpvvh6WnXpp7YpqjSvqw/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh1Ho0vMUY9LsG619QJQJ9hcGJ_Y3yYSm3UM8Mn1yx6UKMKd28LdbT2CM-rsB5A_RsM1505bw79EeIjLFyGhN8-41lDDMHGOapR_tZgqvLGJId3TpOq67tBBKNEpvvh6WnXpp7YpqjSvqw/s1600/Untitled.jpg" /></a></div>
<br /></div>
</div>
<div>
The extensibility of fabrics is reduced but not eliminated by the introduction of miss stitches. Such reduction is considered desirable in jersey fabrics used as alternatives to woven fabrics in outerwear garments.<br />
<br />
<b>Transferred loops</b><br />
<b><br /></b>
A loop that is displaced after being formed so that it combines with an adjacent loop, or so that it appears in a different wale, is said to have been transferred.<br />
<br />
Transferring is used to generate holes in fabric to form lace-like effects. Fig. 2.23 shows a structure and draft of a typical lace fabric, formed by transferring loops on a plain fabric. Transferring can be used to produce structural effects by inclining wales of both plain and rib fabrics. Fig. 2.24 shows a structure and draft of an inclined wale plain fabric. This is also used to produce cables by exchanging two or more groups of wales with one another.<br />
<br /></div>
<div>
Most structural and colour designs in weft knitted fabric fall into the above three categories of modification. These influence the nature of the garments subsequently produced from them, largely because they modify the physical properties of the basic fabrics. They also give a wealth of visual interest to the fabrics.<br />
<br />
Other factors contribute to the complexity of knitted fabrics and to the appearance and properties that characterise them. The following is by no means a comprehensive list:<br />
<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>fibre type, size, colour, lustre, cross-sectional shape etc.;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>yarn type, size, colour, surface nature, contrived irregularities (fancy yarns etc.);<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>loop size;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>constructional details generating colour patterns or structural patterns;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>making a construction with specific properties of weight, insulation, abrasive or washing capabilities etc;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>wet finishes applied to fabrics, e.g. shrink resist, softening, stiffening, anti-creasing, moth proofing etc;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>dry finishes such as pressing, brushing, calendering, setting etc.</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-12341239884094055462017-01-12T02:05:00.001-08:002017-03-01T03:24:34.619-08:00Knitted Garments<div dir="ltr" style="text-align: left;" trbidi="on">
The principal feature of garments made from knitted fabric is that the nature of the final garment and the processing it goes through are affected in a major way by the primary knitting process. It is possible to have four knitted garments which look superficially similar but have been produced by four differing processes (Fig. 1.1). This chapter defines these processes and discusses the relative methods and use of them.<br />
<br />
All knitted garments can be classified into four categories according to general production methods:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>fully cut;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>stitch shaped cut;<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>fully fashioned;<br />
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span>integral.<br />
<br />
<b>Fully cut (Fig. 1.2)</b><br />
<b><br /></b>
The term 'fully cut' describes the processes most akin to making garments from woven fabric. Garments are cut from piece goods fabric, laid up (spread) on to cutting tables. All parts of the garments other than the trims are cut from the ray. Each garment piece has all edges cut, hence the term fully cut.<br />
<br />
The garments are assembled by seaming machines, often of a specialist nature, and trims are added where appropriate. The fabric for this process is invariably knitted on circular knitting machines. Such machines come in a wide range of types but are mostly classified under two headings:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>single jersey or plain web machine;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>double jersey or rib machine.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjL8B3wRDBnrpvmVsQaFYUfMFHta5aHqCGlAFoAMzq8pQou93MGv4RFQG_bVcj1_IDwtwNuLwookVz7nCCI8ysxLXdfc6xEtGc6sSu3qZ_C8uo2N659xPZ0ARXlJhUikwhCQdLy3mXDIbY/s1600/dd.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjL8B3wRDBnrpvmVsQaFYUfMFHta5aHqCGlAFoAMzq8pQou93MGv4RFQG_bVcj1_IDwtwNuLwookVz7nCCI8ysxLXdfc6xEtGc6sSu3qZ_C8uo2N659xPZ0ARXlJhUikwhCQdLy3mXDIbY/s1600/dd.jpg" /></a></div>
<br />
<br />
<div style="text-align: center;">
<u>FULLY CUT GARMENTS , PRODUCTION SEQUENCE.</u></div>
<div style="text-align: center;">
<u><br /></u></div>
<div style="text-align: center;">
Circular knitting of fabric </div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Scouring, bleaching and/or dyeing</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Pressing, calendering or decatizing </div>
<div style="text-align: center;">
or stentering</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Laying up (spreading) of fabric </div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Marking and cutting </div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Assembly</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Examine and mend</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Finish press</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: center;">
Fig. 1.2 Production sequence of fully cut garments</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: left;">
These machines vary in diameter, the number of needles per inch/ centimetre (gauge), the number of courses they can knit in one revolution (number of feeders), and their fabric patterning capabilities. Modern circular machines are capable of extremely high production rates (300 m<sup><span style="font-family: "times new roman" , serif; font-size: 12pt; letter-spacing: -0.1pt;">2</span></sup>/hour).</div>
The fabric varies according to the type of garment to be made and the knitting machinery is usually designed specifically for a particular class of garment: specialist sports clothes and leisure activity clothes, jersey dresses, suits, slacks and other outerwear. Exceptionally 'knitwear' is sometimes produced.<br />
<br />
As already suggested, fully cut is analogous to the processing of woven fabrics but there is one important distinction that influences the whole range of processing. All knitted fabrics and the garments made from them are extensible. Care must be taken with the wet and dry finishing processes to avoid stretching and thus inducing shrinkage potential into the fabric. Care must also be taken with laying up, cutting and finally the making up processes, to avoid distortions.<br />
<br />
Making up of the garments is usually carried out with a three thread overlock stitch (BS stitch type 504), although multi thread chain stitch seams are increasingly being used on underwear, swimwear and leisure-wear.<br />
<div>
<br /></div>
<div>
<div>
<div style="text-align: center;">
<u>CUT STITCH- SHAPED GARMENTS,</u></div>
</div>
<div>
<div style="text-align: center;">
<u>PRODUCTION SEQUENCE</u></div>
<div style="text-align: center;">
<u><br /></u></div>
</div>
<div style="text-align: center;">
flat or circular knitting of blanks</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
rough press</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
cutting</div>
<div style="text-align: center;">
↓ </div>
<div style="text-align: center;">
assembly</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
examine and mend</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
finish press</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: center;">
Fig. 1.3 Production sequence of cut stitch-shaped garments</div>
</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: left;">
<div>
Sewing machine attachments are of major importance for speeding work times. There are general and specific attachments to seaming machines for hemming, binding, elasticating and other seam forms.<br />
<br /></div>
<div>
The attractions of fully cut processes are:<br />
<br /></div>
<div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>the relatively low costs of the fabric produced at high speeds with low labour input;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>the opportunity for scale of production which particularly shows benefits at the cutting stage.<br />
<br /></div>
<div>
The disadvantages are:<br />
<br /></div>
<div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>the relatively high waste factors that occur even with small garment pieces. Such wastage ranges from 17% to 50% and is a significant cost burden on the garments produced;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>the high labour cost of assembly of the garment.<br />
<br /></div>
<div>
<b>Cut stitch shaped (Fig. 1.3)</b><br />
<b><br /></b></div>
<div>
The majority of knitwear is produced by this method, together with a very small production of ladies vests. The general method involves knitting rectangles of fabric relating to the size of the portions of the garment to be made. The pieces, known as 'blanks', have the lower edge of the fabric sealed with a structure known as a 'welt' that prevents laddering and distortions of waistbands and cuffs.<br />
<br /></div>
<div>
The term 'stitch shaped' derives from different stitch structures within the length of the blank that distort it from the rectangle into a shape associated with the human body. Commonly such shaping involves engineered rib waistbands and cuffs that restrict the lower extremity of the garment but are extensible. In ladies vests such waistbands Occur in the middle of the garment blank.<br />
<br /></div>
<div>
<div>
These blanks require minimal preparation for seaming. Cutting involves trimming for length and sometimes for width, followed by cutting neckholes and armholes, lower arms and shoulder shaping.Cutting is still largely carried out by hand, using shears on individual or doubled pieces. Template press cutters capable of dealing with up eight blanks at a time are also employed. Such labour intensive operations are offset by the low wastage figures achieved — 10-20%.<br />
<br /></div>
<div>
It pays to make the blank as near as possible to the exact size of the garment portion, or a width multiple of the garment portions. The knitting machinery employed to produce the blanks is in its mechanised form the most complex of all, although it must he admitted that simple hand flat knitting machines can produce highly complex blanks, with the `programme' being in the brain of the operative.<br />
<br /></div>
<div>
There are two types of knitting machine employed: flat and circular. Both are usually rib machines, with two knitting beds and two sets of needles. Some are purl type, with two beds sharing one set of needles. Flat knitting machines knit blanks with selvedges on the side of the fabric. The blank can be any width up to the total width of the machine bed. Two or more blanks can be knitted at the same time.<br />
<br /></div>
<div>
Flat machines are relatively slow and even with five knitting systems the most advanced machinery makes very few blanks in an hour — 24 maximum and 12 normally. The labour of machine minding and the high capital cost of the machines feature significantly in the cost of a garment.</div>
<div>
Flat machines vary in their complexity with the simple types being used for relatively simple garments. Most machines now are computer controlled and programmed and are built for prodigious versatility of fabric type and patterning. Other mechanical developments of this type of machinery also allow the production of fully fashioned and integral garments, although at the expense of the production rate.<br />
<br /></div>
<div>
The circular machines produce blanks in the form of tubes, the circumference of the tube being related to the diameter of the machine. A particular size of tube may be used to produce a certain size of garment, with minimal waste on the side seams. Various diameters of machines are assembled in a plant to produce a range of garment sizes.<br />
<br /></div>
<div>
Production management of such a plant is extremely difficult as changes of structure in the fabric of the blanks change the circumference of the fabric produced. An 18 in diameter machine may produce a 44 in (112 cm) width of one fabric type and a 38 in (96 cm) width of another. Inevitably either some of the plant remains idle or the plant is fully employed with added wastage of raw materials when cutting small garments from large blanks.<br />
<br /></div>
<div>
The approach now employed to minimise the problems is to have very large diameter machines producing large circumference tubes that are split down the side, opened out and cut into a series of</div>
</div>
</div>
and sleeves to fit the production requirements and mini f widths mise waste. Such bodies a<br />
machine is the Jumberca TLJ-5E, produced in a diameter of 33 in and producing fabrics from 2.5 m to 3 m wide.<br />
<br />
Yet a further approach is the variable circumference machine. This type still knits in a continuous revolving manner but some of the needles around the circumference do not knit. The number of these can vary and they are situated in a block on either side of a space 60° in circumference, that contains no needles. In each revolution of the machine, yarn is cut and trapped when it reaches the gap and knitting recommences on the other side of the gap. Thus the fabric is produced not as a circle but as an open width blank, the width of which can be varied to suit the production requirements, with minimal waste. The patents for this machine type are held by Mecmor who produce the Varitex garment length machine, TEJ 180, with a 33 in diameter and 12 feeders, and the TEJ 2500 with a diameter of 40 in (101 cm), 18 feeders and a maximum knitting width of 110 in (280 cm).<br />
<br />
Like the flat machines, circular garment length machines have been subject to electronic development; computer controls have been fitted to them to handle the complexity of information required to knit a garment blank. Separate programming computers with a Computer Aided Design (CAD) facility are used to produce the tape or disk that is 'read' by the knitting machine.<br />
<br />
The garments are assembled almost entirely by the .use of three and four thread overlock machines (BS stitch types 504 and 506). Seam covering stitches (BS 602) are sometimes used on the facings or 'stoning' of cardigan and back neck seams. Collars are often attached by linked, or increasingly, mock linked seams (BS 101 or 401). Lockstitch seams are used when attaching inextensible trims such as ribbon facings, plackets, leather and woven fabric decorative portions, and tabs and labels.<br />
<br />
Often, in the initial stages of production prior to cutting, the blanks are steamed on an open bed — in the case of acrylics — or pressed — in the case of wool and cotton. To facilitate ease of handling and maintenance of size, two similar blanks are often seamed together temporarily with chain stitch before the steaming. Heavy, rectangular, wire frames are sometimes used to. hold the blanks to prescribed dimensions.<br />
<br />
<b>Fully fashioned (Fig. 1.4)</b><br />
<b><br /></b>
Fully fashioning is the process whereby portions of a garment are shaped at the selvedges by progressively increasing or decreasing the number of loops in the width of the fabric. Such narrowing and widening produces the shape of a piece of garment that would otherwise be generated by<br />
cutting.<br />
<br />
<div style="text-align: center;">
<u>FULLY FASHIONED GARMENTS, PRODUCTION SEQUENCE</u></div>
<div style="text-align: center;">
<u><br /></u></div>
<div style="text-align: center;">
Knitting ribs and garment portions</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Rough assembly</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Scour, dye, mill, shrink-resist finish</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Press</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Cut, neckholes etc.</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Attach collar</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Examine and mend</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Finish press</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: center;">
Fig. 1.4 Production sequence of fully fashioned garments.</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: left;">
Fashioning has two obvious advantages over the two previously described categories of garment making:</div>
<div style="text-align: left;">
<br /></div>
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>there is little or no cutting waste;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>the edges of the garment pieces are sealed and not liable to fraying, so can be joined by simple non-bulky seams.<br />
<br />
Fully fashioned garments are usually associated with knitted outerwear of a particular classical type and with a particular type of machinery: the `straight bar' or 'Cotton's Patent' knitting machine. However, knitted underwear is made on a fully fashioned basis, although the quantity is now very small compared to that made in the 19th century. A similar situation applies to ladies hose which suffered a dramatic eclipse in the early 1960s when a fashion change wiped out an enormous industry virtually overnight.<br />
<br />
Men's heavy rib sweaters are also fully fashioned on hand flat knitting machines, as are fine gauge ladies suits and dresses.<br />
<br />
Increasingly the fashioning capabilities of modern electronically con¬trolled V-bed flat machines are being used for making fully fashioned garments with scope for embellishment using a wide range of patternings. Such a use, with savings of material and making up costs, Will increasingly feature as a development of the stitch shaped industry.<br />
<div style="text-align: center;">
<u><br /></u></div>
<div style="text-align: center;">
<u>INTEGRAL GARMENT (1/2-HOSE) PRODUCTION SEQUENCE</u></div>
<div style="text-align: center;">
<u><br /></u></div>
<div style="text-align: center;">
Knit half hose</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Seam toes</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Wet finish, scour, dye</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Examine and mend</div>
<div style="text-align: center;">
↓</div>
<div style="text-align: center;">
Finish press, set</div>
<div style="text-align: center;">
<br /></div>
<div style="text-align: center;">
Fig. 1.5 Production sequence of integral garment (half hose).</div>
<div style="text-align: center;">
<br /></div>
Making up traditional classical fully fashioned garments takes place in two stages:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>rough making up;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>finished making.<br />
<br />
The rough making up is carried out to join the basic portions of the garment together: front, back and sleeves along the selvedge. Cup seamers are used to provide a single or double chain stitch for these seams. With some styles — saddle shoulders and set-in sleeve jumpers — linking is used to join the shoulder seams, loop for loop.<br />
<br />
The rough made up garment can at this stage be wet processed. This is carried out on the majority of garments that are single coloured, and on some that are multi-coloured. Wet processing involves some or all of the following: scouring, milling, shrink resist and dyeing.<br />
<br />
After drying, hoarding and pressing the finishing making up is carried out, including cutting of necklines, fronts of cardigans and shirts, attaching collars, facings, stollings and buttons, buttonholing etc. Linkers, mock linkers and lockstitch machinery are used.<br />
<br />
Fully fashioned garments made on V-bed machinery are not normally wet processed, and making up is usually by cup seamers, linkers and mock linkers.<br />
<br />
<b>Integral garments (Fig. 1.5)</b><br />
<b><br /></b>
Integrally knitted garments are those that are essentially knitted in one piece with little or no seam. The archetypal example is the beret, which is knitted sequentially in a series of triangles, leaving the beginning and the end to be joined into a three dimensional shape. This principle has also been used to make skirts and jumpers and is used to produce a large proportion of ladies and gents millinery.<br />
<br />
Another integral garment using a combination of tubular knitting and shaping is the men's sock or half hose. To shape the heel and toe of a sock, pouches are formed from extra rows of knitting.<br />
<br />
The third common type of integral garment consists principally of joined tubes — the glove. Tubes are constructed for each of the digits, sometimes with shaped tips, and merge together into the palm portion, (also a tube). Such gloves can now he knitted fully automatically (Shim, Seiki) with no subsequent making up procedures.<br />
<br />
Integral concepts are proposed from time to time for upper body outer-wear garments, and have been the subject of patents. Inhibitory factors to their introduction include lack of competent designers and development technicians, and sheer conservatism on the part of producers.<br />
<br />
The rewards could be considerable, saving both raw material anti labour costs at the expense of lower machine output. There is little question that the electronic V-bed knitting machines in their present state of development, with presser foot or holding sinkers, are easily capable of producing garments in all the integral garment categories.</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-15941521098758567162017-01-06T21:24:00.001-08:002017-03-01T03:24:34.623-08:00Introduction<div dir="ltr" style="text-align: left;" trbidi="on">
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxwOPkaPdeok000vky6qXa53NRJxI_IqqjAlzlf4MZCxOUQJAaiEPvhVGbljYAMJau2hBKICWrtfmL9ZbvzPInVNg3o0SQx5YhExVKITx2osMc8gMvtYONfqfyHKHLprTN6jTXeS0IPTw/s1600/Untitled.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="313" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgxwOPkaPdeok000vky6qXa53NRJxI_IqqjAlzlf4MZCxOUQJAaiEPvhVGbljYAMJau2hBKICWrtfmL9ZbvzPInVNg3o0SQx5YhExVKITx2osMc8gMvtYONfqfyHKHLprTN6jTXeS0IPTw/s400/Untitled.jpg" width="400" /></a></div>
<br />
<br />
When most people. arc confronted with the term 'knitting' they immediately think of Aunt Agatha's Christmas jumpers, in excruciating colours, the necks of which will not stretch over the head. This book is not about Aunt Agatha's jumpers. Knitting is one of the most important processes for producing garments and world wide represents a considerable and increasing percentage of the population's apparel.<br />
<br />
Knitting is used to produce garments that cover every part of the human body, in a wide range of garment types from socks, caps, gloves and underwear to upper and lower body garments varying from T-shirts to formal jackets. In spite of this range, the treatment of the fabric to produce various garments and the properties of the garments produced have a great deal in common, and it is the intention of this book to explore that commonality.<br />
<br />
This common theme is connected with the knitted fabric property of extensibility. This is in sharp contrast to the general rigidity of most woven fabrics. The industries dealing with the production of knitted garments remain separate from those dealing with woven garments, except for the overlap occurring with dresses, suits and other outerwear garments produced from jersey fabrics.<br />
<br />
Within Government industrial statistics the firms producing knitted " garments are not classified as part of the clothing industry but as part of the textile industry. Nevertheless, in spite of the separateness of the knitted garments industry, within the fully cut sections there is a considerable sharing of production technique with the industry using woven fabrics, in pattern generation, lay planning, cutting, and production planning and organisation. Many hooks have been written about woven fabric clothing technology; a few mention some of the areas of overlap between woven and knitted fabric, but there are no books dealing with the particular and general. techniques of producing clothes from knitted fabric. It is the intention of this book to begin to redress the balance.<br />
<br />
There are indeed very few books dealing with the industrial aspects of-knitting (see bibliography) and these tend to deal primarily with knitting machines and their 'products, not the subsequent processes that create garments. The primary production of knitted fabric is not dealt within this book, although an introductory chapter on knitted fabric structures is included.<br />
<br />
There are many books covering hand-knitting techniques and the production instructions for creating garments. This is to be expected, for hand knitting is one of the oldest of man's construction techniques, and is also one of the world's most popular pastimes.<br />
<div>
<br /></div>
<div>
<div>
<b>Hand knitting</b></div>
<div>
<b><br /></b></div>
<div>
Hand knitting precedes machine knitting as a technique by many hundreds, if not thousands, of years. Its area of origin and time of invention are unknown. There is conjecture that the mountainous areas of Persia, now Iraq, Iran and Afghanistan were the origin. Similar claims have been made for the Holy Land, Israel, Jordan, Syria and Lebanon; also the Atlas mountains of North Africa provide a likely site. These are all areas associated with the domestication of sheep, and the likely connection between wool fibre and knitting. Wool fibre, which is composed of protein, would decay rapidly in the sorts of climate associated with mountain areas. This would help explain the lack of early examples of knitting. Archeological investigation in these areas has tended to concentrate on the great civilisations, not peasant culture. It is also possible that references to knitting in early writings have been missed or misinterpreted.</div>
<div>
<br /></div>
<div>
In medieval Europe hand knitting was an important industry and socks, caps and knitted gloves were common products. Hand knitting had many obvious advantages, i.e. the simplicity and portability of the production apparatus, the lack of a cutting and making up process needed to complete a garment, knitted in the round (integral), the lack of complex finishing techniques, the simplicity of fit, and the stretch allowing various shapes and sizes of people to be able to wear one size of garment.</div>
<div>
<br /></div>
<div>
By the second half of the 16th century hand knitting had developed into an advanced craft, with stockings for the gentry and nobility being knitted from extremely fine silk threads on pins that were little more than fine wire. These stockings were usually richly embroidered and embellished with threads of coloured silk, gold and silver. The prices were very high and and the hose were regarded as the most important part of a gentleman's wardrobe. The lower orders wore stockings of worsted sun</div>
<div>
wool or linen or hemp, knitted or bias cut from woven fabric.</div>
<div>
<br /></div>
<div>
<b>Knitting machines</b></div>
<div>
<b><br /></b></div>
<div>
In 1589, in the reign of Queen Elizabeth I, the Reverend William Lee, a curate of Calverton in Nottinghamshire, presented himself at the Court of the Queen with a request for Letters Patent for his newly invented knitting machine. This machine was remarkable in many ways: it was the product of lateral thinking in that it used an entirely different method to produce a familiar product; it employed complex interacting motions unlike any other machine in existence; and it was arguably the first machine to concentrate on increasing the productivity of a process for its own sake (i.e. the start of the Industrial Revolution).</div>
<div>
<br /></div>
<div>
<div>
This first machine produced coarse knitting — peasant hose — and although it reportedly caused a sensation at Court and was the object of marvel, Elizabeth dismissed the application with the following words:</div>
<div>
<br /></div>
<div>
'My Lord I have too much love for my poor people who obtain their bread by the employment of knitting, to give my money to forward an invention, that will tend to their ruin by depriving them of employment, and thus make them beggars. Had Mr Lee made a machine that would have made silk stockings I think 1 should have been somewhat justified in granting him a patent for that monopoly, which would have affected only a small number of my Subjects; but to enjoy the exclusive privilege of making stockings for the whole of my Subjects, is too important to be granted to any individual'.</div>
<div>
<br /></div>
<div>
Under the patronage of Lord Hunsdon, Lee persisted and produced in 1598 a refined version of his frame, able to produce silk stockings. This machine contained, it is thought, 20 needles to the inch rather than the 8 needles per inch of the original. He still did not acquire the desired document from Elizabeth, or James I, and, enticed by the French envoy the Marquis de Rosny, he moved to France with his brother James, six frames and nine knitters. The frames were set up in Rouen and succesfully operated as a small industry.<br />
<br /></div>
<div>
William Lee stayed in Paris, where, after the murder of Henry IV, he was declared <i>persnnna non grata</i>. He died in Paris in 1610, destitute and in low spirits before his brother James could rescue him.</div>
</div>
<div>
<br /></div>
<div>
</div>
</div>
<div>
<b>Knitting industry</b><br />
<b><br /></b>
James, on learning of the death of his brother in such lowly circumstances, removed the machines back to London where the changed economic and political climate enabled an active industry to be started, with people clamouring to be apprentices to the new pursuit. James made a modest profit from the sale of the machines, returned to Nottinghamshire and with Aston, a miller of Thornton, produced frames improved with Aston's invention of a fixed additional sinker bar.<br />
<br />
The industry was now set for rapid and consistent expansion, lasting for 200 years until the slump initiated by the French Revolution and subsequent Napoleonic wars produced the first experiences of industrial recession (Thomis 1969.)<br />
<br />
Such was the completeness of the frames conception that frames of virtually identical construction were still used in a productive capacity in Nottinghamshire in the 1970s, to produce shawls.<br />
<br />
The industry during the 17th century developed as a typical Guild-organised cottage industry. The Framework Knitters Company, established by Royal Charter and based in London, regulated the industry in England and Wales but not in Ireland and Scotland.<br />
<br />
The restrictive nature of the Guild system in respect of knitting become intolerable by the beginning of the 18th century, and moves were made to escape its strictures. Initially such moves were confined to the establishment of branches of the industry in Dublin and the Scottish Borders, but eventually they led to the breakdown of the Guild authority in the Midlands, aided by a Parliamentary sanction of 1753. During this period the Framework Knitters Company took legal action to attempt to control<br />
the trade and move it back to London.<br />
<br />
By 1750 the distribution of frames in the country was:<br />
<br />
London<span class="Apple-tab-span" style="white-space: pre;"> </span> 1000<br />
Surrey<span class="Apple-tab-span" style="white-space: pre;"> </span> 350<br />
Nottingham<span class="Apple-tab-span" style="white-space: pre;"> </span> 1500<br />
Leicester<span class="Apple-tab-span" style="white-space: pre;"> </span> 1000<br />
Derby<span class="Apple-tab-span" style="white-space: pre;"> </span> 200<br />
East Midlands rural sites<span class="Apple-tab-span" style="white-space: pre;"> </span> 7300<br />
Other English towns and Scotland<span class="Apple-tab-span" style="white-space: pre;"> </span> 1850<br />
Ireland<span class="Apple-tab-span" style="white-space: pre;"> </span> 800<br />
<br />
A total of 14 000 - a considerable industry.<br />
<br />
The 18th century represented two interconnected revolutions for the knitting industry, with a subsequent effect on the whole of the textile industry. The first was a spate of inventiveness that modified the frame. The second was the diversification of the product into articles other than hose. Both these trends led to rapid expansion of the industry.<br />
<br />
<b>Modifications to frames</b><br />
<b><br /></b>
The modifications of the frames were numerous and many inventions were aimed at circumventing the inventions of others. Most of the modifications and inventions occurred in or near Nottingham town.<br />
Among the most important modifications were:<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>the rib frame;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>selection devices to aid patterned loop transfers, including pin drums and jacquard's;<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>the warp frame;<br />
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span>selection devices to produce tucked fabrics.<br />
These led ultimately to the evolution of warp knitting and of true twisted lace. Such expansion led to a shortage of yarn, particularly of the newly introduced short staple cotton. (The first cotton, from India, was knitted in Nottingham in 1730.)<br />
<br /></div>
<div>
<div>
First Hargreaves (1767)„ind then Arkwright (1769/72) set up their spinning mills in Nottingham. Both men were from Lancashire but were attracted to the Nottingham area by the demand for yarn, the availability of capital, the skill of local engineers and the theoretical availability of a workforce used to working with machines. What was lacking, however, was power. Watts' steam engine was invented in 1769 and was not available to Arkwright until much later. His Nottingham frames were driven by horse or mules: Hargreaves' machines were powered by hand. Felkin (1967) is of the opinion that, if the steam engine had preceded Arkwright's frame, the cotton industry would have been located in the East Midlands.</div>
<div>
<br /></div>
<div>
Arkwright moved to Derbyshire for water power and eventually hack to Lancashire where calico and Fustian weaving expanded rapidly.</div>
<div>
<br /></div>
<div>
<b>Diversification of product</b></div>
<div>
<b><br /></b></div>
<div>
The diversification of the product was connected to the inventions: sometimes an invention suggested a product and sometimes a perceived market led to an invention. Such see-sawing was to become the characteristic of knitting industry development up to the present time.</div>
<div>
<br /></div>
<div>
The other associated characteristic, which is not exclusive to knitting but is more exaggerated than in any other industry, is the tendency to produce multiple solutions to one problem. This can best be explained in an example. At the height of the double-jersey/jacquard fabric boom of the 1960s, every knitting machine builder produced an exclusive, patented, needle selection mechanism to carry out the function of lifting needles to knit or leaving them down to miss. There were possibly over 20 different mechanisms available at the same time to carry out the same function.</div>
<div>
<br /></div>
<div>
Examples of this can still be found in electronically controlled V-bed knitwear machinery, where every machine builder has progressed along separate lines and produced different machines, computers and, most important, languages to deal with the same problems and functions.</div>
<div>
This dates back to the mechanics and engineers in Nottingham (and Saxony) all trying to circumvent one another's mechanisms to produce the same product. It is said that Nottingham was the largest outlet in Europe for powerful telescopes and can lay claim to another first in industrial development industrial espionage! In no other industry is it possible to make a seemingly identical product by so many alternative routes.</div>
<div>
<br /></div>
<div>
The original purpose of the frames was to take advantage of the demand for hose. The wearing of hose (defined here as tight fitting leg covering) by men became firmly entrenched in Italy during the Renaissance, and rapidly spread to the rest of Europe. This fashion during the 15th century involved the wearing of what we would recognise as tights - close fitting garments enveloping the whole of the lower body from the waist downwards. Such garments were constructed from bias cut woven fabrics, or leather, but it is not impossible that sonic were knitted. They were called `breeches' and were often worn with `hosen' - short socks or lightweight hoots worn over the tights.<br />
<br />
Later, as the fashion progressed into the 16th century, the hoses covered most of the leg and the breeches became ballooned shorts. This fashion was to dominate men's dress of all classes up to the start of the 19th century.<br />
<br />
From approximately 1540 the hose were almost exclusively knitted. During the reign of Elizabeth 1, richly embellished hose became one of the most important items of men's dress. Contemporary accounts speak of men spending half their annual income on J single pair of hose.<br />
<br />
I am sure that such commercial implications were not lost on William Lee, although he was not to benefit personally. William Lee's frame was flat and could therefore only produce flat pieces of fabric. These could he shaped at the edges and garments could he built up of several pieces to produce complexity of shape, or to remove seams from awkward places such as the soles of the feet. Essentially, however, the hose were seamed together by hand and were of the type that we now know as fully fashioned, with a main seam down the back of the leg. The hand knitters were not restricted to the flat form and could produce hose in the round<br />
(integral garments).<br />
<br />
After the wide introduction of Lee's frame, from 1620 onwards, hand knitting of hose diminished except for the very coarsest of articles. Nevertheless, hand knitting was still used to produce items like hats and gloves and possibly seamen's jumpers.<br />
<br />
Tradition has it that with the break-up of the Spanish Armada, and the subsequent blockade of the English Channel, ships of the Armada headed northwards to round Scotland and head back for home via the Atlantic ocean. This part of the story is undoubtedly true as wrecks and founderings are reported all along the route.<br />
<br />
The Spanish sailors carried their knitting skills with them and there are highly developed patterned knitting skills in all the seaboard places where the Armada ships could have called or foundered, including the Scottish east coast, Orkneys, Shetlands, Faroes, Norway, Iceland and the Irish Aran Islands. In the coastal ports of the North sea and North Atlantic, the upper body garments that we now know of as knitwear developed. They never became fashion in the widely worn sense of the word and were not, until recently, the objects of commerce, but they produced for fishermen and seamen essential items of protective clothing.<br />
<br />
The product of the frame, i.e. the major output of knitting, was one type of garment - hose - until early in the 18th century when some diversification's took place; other garments, normally the province of hand knitting, were produced such as gloves, hats, scarves and shawls. These were essentially shaped garments made like the hose, either fully fashioned or integral.<br />
<br />
There were other interesting developments. After the introduction of cotton into Nottingham in 1730 frame-work knitters began knitting lengths of simulated lacework using loop transfer techniques. Such 'point lace' created a boom, both in the commercial sense and in a spur to inventiveness.<br />
<br /></div>
</div>
<div>
Also over the same period other garments were made from knitted fabric, which was cut and treated in a similar way to woven fabric. Jackets, breeches and waistcoats are all items produced during this period of which there are examples in existence.<br />
<br />
Later, in the period 1790 to 1820, such cut techniques when applied to hose to cheapen them were a major factor in the Luddite Rebellion in the Nottingham area. The knitters strongly objected to the implied productivity improvements, the subsequent lowering of reward to themselves and the lowering of the quality of the goods produced. A copy of their petition has recently been published (Knitting International) and provides a remarkable insight into the problems of the day.<br />
<br />
The industry was also experiencing another unique event — a major change in fashion for men, away from the weaving of full hose to the wearing of trousers.<br />
<br />
In the 19th century power was applied to the knitting machine, the first circular machines appeared, William Cotton's patent revolutionised fully fashioned hosiery production, and Matthew Townsend's latch needle enabled consecutive knitting and selection to knit and miss to take place.<br />
<br />
The product diversified still further during this period and knitted underwear became a reality, followed at the end of the century by sportswear and swimwear (exposed underwear) followed closely by knitted outer garments (knitwear).<br />
<br />
During the period 1880 to 1910 knitwear became established as an item of female fashion. The basic methods and division of production were established during this period and are still with us today. These basic methods are:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span><i>Fully fashioned Knitting</i> shaped portions of fabric in the flat;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span><i>Cut stitch shaped Knitting</i> of made to size portions of fabric, with some shaping introduced by changing of stitches;<br />
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span><i>Fully cut knitted</i> <i>piece goods</i> Lengths of fabric from which garments are cut in masses;<br />
(4)<span class="Apple-tab-span" style="white-space: pre;"> </span><i>Integrally knitted</i> The shape is generated in the round during knitting, leaving little or no seaming.<br />
<br />
<b>Twentieth century developments</b><br />
<b><br /></b>
Development in the 20th century has largely involved increasing the productivity of knitting machines and making them more versatile in their patterning scope. The knitted garment is now established as part of everyday dress and most people, irrespective of age or gender, are usually wearing two or more knitted garments most of the time.<br />
<br />
Fashion or society in its cycles sometimes decrees that knitted garments are the main form of clothing for females. The polyester clothes of the 1960s and early 1970s are an example, and the knitwear-dominated late 1970s and early 1980s are another. Such cycles in fashion prove concerting, if not plain disastrous, to the knitting industry. The industry contributes to its vulnerability by divisions into specialist sectors. Such sectors tend not to respond to fashion changes readily, either because of technical limitations and lack of expertise in technical and design development, or a complete failure to recognise market opportunity.<br />
<br />
Some sectors remain aloof from fashion directly for long periods of time, but are subject to other trends. The manufacture of basic under-wear, for example, trades on the basis of a utilitarian necessity but is subject to pressure from alternative production sources, being ideally located in areas of low labour costs.<br />
<br />
Even basic underwear is slowly subject to fashion changes and some-times itself evolves into fashionable items of clothing. The T-shirt that is currently ubiquitous wear all over the world evolved from vests.<br />
<br />
There is currently a discernible trend in production techniques that may, over a long period, have important consequences for the knitting industry and its products. There has always been concern over the waste of raw material that results from cutting garment shapes out of flat materials. This can, in extreme cases, represent 40-50% of the whole.<br />
<br />
It is recognised that knitting in the fully fashioned or integral modes enables the waste of value-added raw material to be largely eliminated. For a long time, however, the technology of knitting machinery has limited the range of garments that can be produced by these methods. Fully fashioned outerwear, for example, has long been confined to plain fabric with embellishments of stripes, loop transfer, tuck stitches and intarsia.<br />
<br />
The advent of computer controlled V-bed knitting machines has changed the situation dramatically. The ability to fully fashion on a wide range of fabric types is now possible. Inhibitory factors, however, are:<br />
<br />
(1)<span class="Apple-tab-span" style="white-space: pre;"> </span>the added skills needed on the part of the designer and machine programmers to cope with the complexities;<br />
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>the increase in machine production time involved in making fully fashioned garments as opposed to cut stitch shaped.<br />
<br />
This second factor is seen by most manufacturers as the biggest stumbling block because such decreases in productivity raise the proportion of the cost of the garment that is involved with the high capital value of the knitting machines and the fixed overheads. This is a highly debatable subject, balancing the savings on raw material and making-up labour costs against the loss of overall production.<br />
<br />
The next step in this progression is to begin to lower the seaming content of the garment. Again, development of the latest computer con¬trolled V-bed knitting machines to include fabric controlling sinkers (Stoll SMC and Shima Seiki SES) allows garments to be integrally shaped by a wide variety of methods. Such developments have potentially more savings than fully fashioned. But there are inhibitory factors:<br />
<br /></div>
<div>
<div>
(1) the added skills needed of the designers and programmers;</div>
<div>
(2)<span class="Apple-tab-span" style="white-space: pre;"> </span>the consequent decrease of production from capital invested;</div>
<div>
(3)<span class="Apple-tab-span" style="white-space: pre;"> </span>the argument that a fault occurring during knitting damages a whole garment.</div>
<div>
It is my contention, however, that production will move strongly in a progression, initially for knitwear but ultimately for all knitted articles, of:</div>
<div>
<br /></div>
<div>
Fully cut →<span style="background-color: white; font-family: "arial" , sans-serif; font-size: x-small;"> </span>stitch shaped cut →<span style="background-color: white; font-family: "arial" , sans-serif; font-size: x-small;"> </span>fully fashioned → integral</div>
<div>
<br /></div>
<div>
I am strengthened in my argument in that three garment types have moved along this progression successfully. These are half hose and hose, gloves and hats.</div>
<div>
<br /></div>
<div>
These principles will be looked at in a separate chapter devoted to integrally knitted garments.</div>
</div>
</div>
Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-41713048408181877862014-06-09T00:33:00.000-07:002017-03-01T03:24:34.656-08:00New levelling agent concept for polyamide<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Abstract</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dyeing PA fibres and their blends is a real challenge to textile manufacturers! In practical use it is known that for sophisticated PA dyeings the following becomes essential during the whole dyeing process: an accurate pH value and temperature control. For producing high-quality fabrics, levellers are required that have affinity to the dye or to the fibre, depending on their task.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Products with dye affinity are used as levelling agents and have a pseudo-cationic character; fatty amine ethoxylates are very frequently used. They form a dye-auxiliary complex, dissociating bit by bit in the dye bath with increasing temperature, facilitating the exhaustion of the dyes onto the PA fibre.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Auxiliaries with fibre affinity are often based on sulphonic acids and thus are anionic. They are normally applied for preventing streakiness on PA fabrics, since they exhaust on to the fabric instead of the dyes in the dye bath. For achieving good dyeing results on streaky-dyeing fabrics, even with a critical dye trichromate, the right auxiliary combination has to be found. In this article such an auxiliary system is presented, with SARABID IPD and IPF, which also facilitates the even dyeing of very critical dyeings without any problems.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Introduction</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Today’s market puts high demands on modern textiles made of polyamide. The new CHT levelling-agent concept can fulfil these demands. Our innovative product system, consisting of SARABID IPD and SARABID IPF, accurately regulates the dyestuff exhaustion and helps guarantee level dyeing results, even on barré dyed polyamide articles.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Module Component 1: SARABID IPD</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Influence on the levelling capacity</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">SARABID IPD has affinity for the dye and forms a dye-auxiliary-complex with the anionic dyes, which dissociates bit by bit in the dye bath with increasing temperature, enabling the dyes to exhaust evenly on to the PA fibre. SARABID IPD promotes the exhaustion behaviour of the individual dye components throughout the complete temperature profile and provides optimum bath exhaustion. For demonstrating the efficiency of SARABID IPD, some test methods are described in the following chapters. The levelling capacity of a levelling agent is illustrated by means of a step test, verifying both the levelling effect (mobility of dyes on the fibre) and the synchronisation effect (adjustment of dye exhaustion speed).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Test Description</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In a step test, individual dyeings are removed at different temperature intervals during the dyeing process and replaced by an undyed sample. For the test series, polyamide material of the kinetic fibre type 3-4 was used, ie. a PA fibre type with normal exhaustion (kinetic fibre type 1-5 is determined with a simple dyeing test, which may be requested separately).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Acid dyes from the BEMACID N range were selected as test dyes. BEMACID N dyes are acid dyes of medium size with one sulpho group. The migration capacity of this dye class is moderate but can be clearly improved by adding a leveller with dye affinity. This is shown in the comparative dyeing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The test was carried out on the laboratory dyeing machine Mathis- Labomat:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">100 % PA 6.6 knitwear, ready for dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">LR 1:10</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Initial dyeing temperature: 30°C</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Heating rate: 1°C/min</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">pH 5.5 with NEUTRACID BO 45 (buffer system)</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">0.25% BEMACID Yellow N-TF</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">0.50% BEMACID Red N-TF</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">0.75% BEMACID Blue N-TF</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The result of the step test (Figure 1)</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMCxGIWzbHu3CobmLi75ENx3ZBZMa6NTR4A5L940VfevWGqHhLKKo-NArDOvxqAlsgIWc4Qe91-ept0CSqIDQhvuIOOBUscFBPVwTd1GZ9iPR4-QORayVDx2AyZ1TqAnENatcwiD18OD0/s1600/articleImage-4551.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMCxGIWzbHu3CobmLi75ENx3ZBZMa6NTR4A5L940VfevWGqHhLKKo-NArDOvxqAlsgIWc4Qe91-ept0CSqIDQhvuIOOBUscFBPVwTd1GZ9iPR4-QORayVDx2AyZ1TqAnENatcwiD18OD0/s1600/articleImage-4551.jpeg" height="320" width="286" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> shows both an even as well as a synchronous dyestuff exhaustion with SARABID IPD: In combination dyeings, SARABID IPD aligns the exhaustion behaviour of individual dye components, since it controls the exhaustion speed of the dyes in the heating phase and promotes an even dye distribution at boiling temperature in the migration phase. The same applies for 1:2 metalcomplex dyes. Besides the levelling capacity, the migration capacity of a levelling agent is also of major importance in PA dyeing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Influence on the migration capacity</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">SARABID IPD increases the migration capacity of the dyes by reducing the dye affinity to the fibre. This is tested by a migration test.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Test Description</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In a first step a dyeing, using a poorly migrating acid dye, is produced in the exhaust process on a 100 % PA 6.6 ready for dyeing knitwear (fibre kinetic type 3-4, normal exhaustion). In a second step a blank dyeing is simulated at a 1:1 ratio with the undyed PA 6.6 knitwear ready for dyeing. Afterwards the levelling between the originally dyed and undyed part is evaluated. The closer the colour sample is adapted to the colour depth of the undyed sample, the better the migrating effect of the auxiliary. The levelling capacity can also be evaluated in this test, due to the total visual evaluation of the dyeing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Step 1: Original dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The dyeing was carried out on the laboratory dyeing machine Mathis-Labomat:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">100 % PA 6.6 knitwear, ready for dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">LR 1:10</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Initial dyeing temperature 40°C</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Heating rate 1°C/min</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Constant pH 5.5 with NEUTRACID BO 45</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">0.70 % BEMACID Navy N-5R</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">98°C, 45 min</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Then rinse warm and cold</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Step 2: Levelling test</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The dyed PA fabric is treated blank at a 1:1 ratio with the undyed PA fabric using constant process parameters in the following way:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">LR 1:10</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Initial dyeing temperature 40°C</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Heating rate 1°C/min</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Constant pH 5.5 with NEUTRACID BO 45</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">x % SARABID IPD</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">98°C 45 min</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Then rinse warm and cold</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Step 3: Visual evaluation of the migrating and levelling effect of the dyeing without auxiliary in comparison with the dyeing with SARABID IPD.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In the migration phase SARABID IPD promotes an even distribution of the dyes at boiling temperature (Figure 2).</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDlHIAvT4L3xDmsA5GAL6AWVrqt2XiQqooS34uFV0Gv_nyty3nrFGJ6iLjm1SDjY9YSA-g7MrNHABx6puOj73qOZgf0C3SFV9ISTqzx1lbmGkpdtVDHiQ5p0btvDk74_NgLUu9TV1dOkI/s1600/articleImage-4561.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjDlHIAvT4L3xDmsA5GAL6AWVrqt2XiQqooS34uFV0Gv_nyty3nrFGJ6iLjm1SDjY9YSA-g7MrNHABx6puOj73qOZgf0C3SFV9ISTqzx1lbmGkpdtVDHiQ5p0btvDk74_NgLUu9TV1dOkI/s1600/articleImage-4561.jpeg" height="320" width="297" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Product Properties of SARABID IPD</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">General properties: promotes surface evenness </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Low foaming, environmentally friendly levelling agent for acid and 1:2 metal complex dyes</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">GOTS-listed for PA blends</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Improves the combination behaviour of acid dyes </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Excellent suitability for DD carpets to achieve high contrasts </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Reduces the dye’s strike rate on quickly absorbing polyamide fibre types, in particular in the carpet and automotive sector providing thus an even application of dyes throughout the complete dyeing process </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Does not contribute to fogging</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dyes polyamide/wool blends for improving the tone-in-tone dyeing with selected acid dyes</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Ensures a level dyeing, even on unlevel dyed articles.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Preferred Application of SARABID IPD in polyamide dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Clothing: hosiery, socks, outdoor, sportswear and swimwear, underwear, etc </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Home textiles: residential and commercial carpets (eg. differential dyeing, high contrasts), upholstery and furnishing fabrics, etc</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Technical textiles: tapes, straps, sewing threads, ropes, filters, etc.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Module Component 2: SARABID IPF</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">SARABID IPF is the anionic component and has affinity for the fibre. It levels differences in affinity caused by the material because the components with fibre affinity stick to the cationic charges of the polyamide fibres before the dye can exhaust unevenly onto the fibre. The component with pure fibre affinity shows no synchronisation effect and has no influence on the exhaustion behaviour of the dyes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">To achieve optimum efficiency SARABID IPF is added prior to the dye.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Influence of the pH value and temperature on the exhaustion capacity</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The best exhaustion capacity of SARABID IPF is in the acid pH range and at boiling temperature. The exhaustion capacity is demonstrated with the example of 2.0 % SARABID IPF on a PA 6.6. knitwear (normal exhaustion), LR 1:10, heating rate 1°C/min. The exhaustion curve shows the following:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The exhaustion capacity decreases towards the neutral range; with a higher temperature the percentage of bath exhaustion of SARABID IPF increases.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Thus, the exhaustion curves demand the following dyeing process parameters: if affinity differences caused by the material are to be efficiently prevented in polyamide materials, SARABID IPF is to be added to the dyeing liquor at the beginning, the pH value is adjusted to approx. pH 4.5 and the dyeing material is pretreated with the stated additives at boiling temperature for 10 - 15 min. Then, the material is cooled down to the required initial dyeing temperature in accordance with the polyamide fibre quality in use. Only then is the pH value corrected depending on the dye selection, and the dye and the levelling agent with dye affinity – SARABID IPD – are added. SARABID IPD reduces the exhaustion speed of the dyes and thus has a levelling effect. This complex dyeing process is well known as the so-called ‘pre-boiling method’ (Figure 3).</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEil9x9C8joJiDCDLZxEMe8hi5blQgmKR2u2kBhWcjNCH7wAfcnGPDyFjbARpRN00KTTxc5zaopl2KmsOyaANq96m62T1z32FjNedqf74Ri6IXZD19sCijeo7Ba-cYusoI_dCU8HpvWQXj4/s1600/articleImage-4571.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEil9x9C8joJiDCDLZxEMe8hi5blQgmKR2u2kBhWcjNCH7wAfcnGPDyFjbARpRN00KTTxc5zaopl2KmsOyaANq96m62T1z32FjNedqf74Ri6IXZD19sCijeo7Ba-cYusoI_dCU8HpvWQXj4/s1600/articleImage-4571.jpeg" height="230" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Elimination of streakiness caused by the material: influence of the exhaustion degree of dyes with the presence of SARABID IPF in the dye bath</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">SARABID IPF shows the best exhaustion behaviour on to the polyamide fibre at a pH value of 4.5 and a temperature of 98°C. But how do dyes behave in the dye bath? The dye-exhaustion capacity is demonstrated with the example of C.I. Acid Red 199 (0.3 % application amount) together with different application amounts of SARABID IPF in the dye bath on a PA 6.6. knitwear (normal exhaustion), LR 1:10, heating rate 1°C/min, pH 4.5. The exhaustion curve shows the following (Figure 4):</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZ6mukio3DAqeBRj2zqqErEh3cIizh63YxV5cMlnT7jjlWru8jfPFZMrBxL8zFlm896WYPcaBIf5FtGSXrf83Fqf02VkbIkgka7pkZY_h4aiQgy6U8xE8AXQP-DEVgoC7eVmJMq_GNf5Q/s1600/articleImage-4581.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZ6mukio3DAqeBRj2zqqErEh3cIizh63YxV5cMlnT7jjlWru8jfPFZMrBxL8zFlm896WYPcaBIf5FtGSXrf83Fqf02VkbIkgka7pkZY_h4aiQgy6U8xE8AXQP-DEVgoC7eVmJMq_GNf5Q/s1600/articleImage-4581.jpeg" height="226" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The exhaustion degree of the dye is clearly slowed down with the presence of SARABID IPF. The higher the application amounts of SARABID IPF, the more strongly is the dye held back in the bath. A positive effect is that these properties level out differences in shade.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">SARABID IPF particularly eliminates streaks that are caused by structural differences in the PA fibre. Dyeings with an even surface are produced. The dyeing example shown in Figure 5, dyed with 1:2 metal-complex dye, shows the </span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgkWJjfJqgZIIePXzGHhs_x4BovtaDjoWSEsJQvx-43F7BzaVt1jKV8-w4f0wfjIU4zW0I4GGrDDABEybeeEjfZnoRlwHiA_PCIwh-s1Pgp2JDr2fe4X_j5sZrDUGSUxfOK8g_uF-Bd3Dc/s1600/articleImage-4591.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgkWJjfJqgZIIePXzGHhs_x4BovtaDjoWSEsJQvx-43F7BzaVt1jKV8-w4f0wfjIU4zW0I4GGrDDABEybeeEjfZnoRlwHiA_PCIwh-s1Pgp2JDr2fe4X_j5sZrDUGSUxfOK8g_uF-Bd3Dc/s1600/articleImage-4591.jpeg" height="320" width="227" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">comparison:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Compatibility with a levelling agent with dye affinity</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">SARABID IPF is compatible with SARABID IPD. Both products have a good migrating and levelling effect if used together in the dye bath. Product properties of SARABID IPF General properties: covers streakiness; levels differences in affinity caused by the material when dyeing PA with 1:2 metal complex and acid dyes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Low foaming, environmentally friendly</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">GOTS-listed for PA-blends</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Efficient as an anionic retarder. SARABID IPF slows down and homogenises the exhaustion of dyes in the heating phase promoting thus their evenness</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Reduce or minimise contrasts for PA DD-carpets with acid dyes</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">When dyeing fabrics with strong affinity differences we recommend either carrying out the known but time-consuming ‘pre-boiling method’ or carrying out a special dyeing process together with MEROPAN LS. This is a special acid donor being added without moving the pH value abruptly into the acid dyeing range (more details can be taken from the separate CHT information brochures on this special dyeing process)</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">No impact on the colour and light fastnesses</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Preferred application of SARABID IPF in polyamide dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Clothing: above all sportswear, swimwear, etc</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Home textiles: residential and commercial carpets and carpets for personal transport (eg. for differential dyeing carpet fibres in order to prevent contrasts)</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Is There a Simpler Alternative?</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Many dyers, particularly commission dyers, presently work with varying polyamide qualities. The fabric is delivered to the company in the morning and in some cases needs to be finished and ready for delivery by the next day. They do not have the time to examine individual polyamide qualities in terms of their kinetic fibre-dyeing behaviour and material differences caused by the structure by means of pretrials in their own laboratory.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For facilitating just-intime finishes we additionally developed a combination product, consisting of SARABID IPD and SARABID IPF, which levels out and prevents streakiness, particularly on varying PA qualities and in general for an easier handling and lower storage cost. SARABID IPM unifies the product properties of SARABID IPD and SARABID IPF.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Product properties of SARABID IPM</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">General properties: promotes surface evenness and levels out streakiness caused by the material. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Multifunctional leveller for dyeing polyamide</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">User-friendly</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Low foaming, environmentally friendly</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">GOTS-listed for PA-blends</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Preferred application of SARABID IPM in polyamide dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> For varying polyamide qualities</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Conclusion</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">CHT offers textile finishers a new attractive package of innovative levelling agents for polyamide. The system is based on modules for highest flexibility and the new product range is designed to help textile finishers meet top quality requirements.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-8297907012566963252014-06-09T00:26:00.000-07:002017-03-01T03:24:34.718-08:00Development of Composite Textile Structures for Wound Dressing Applications<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Abstract</span></strong></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The paper discusses the development of novel and responsive nonwoven composite structures containing gelling materials for wound management. The study mainly focused on the development of novel ‘all-in-one’ collagen-booster therapeutic nonwoven wound dressings that also provide essential functional properties such as high absorption, vertical and lateral wicking, antibacterial and acidic pH properties.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The developed composite wound dressing consists of carboxymethylcellulose (CMC) fibre and also it was reinforced with polylactic acid (PLA) fibre. The composite structures were engineered and produced by making use of the needlepunching technique. The machine settings were optimised during nonwoven production in order to obtain a simulated 3D fabric structure. The simulated 3D fabric structure is expected to have an increased surface area for higher absorption. The produced composite wound dressings were treated with two different collagen boosters at 4% (w/v) by using the spray method.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The details of the collagen boosters have not been disclosed in this paper due to the Intellectual Property Rights (IPR) issues. The selection of collagen boosters have been based on previous studies. They were selected after screening the collagen enhancing property of the various individual chemicals in the literature.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">It is evident from the literature that the selected collagen boosters are essential for collagen synthesis. Another important benefit of using collagen booster treatment is that it allows the maintenance of an acidic pH environment at the wound area. It is well known that acidic pH reduces the wound healing time and enhances the wound healing process. Furthermore, one of the collagen boosters promotes not only the proliferation of the epithelial cells in wounds but also can provide antibacterial action.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The results demonstrate that the PLA fibre reinforced CMC composite dressing has enhanced wicking properties which help to minimise the pooling of exudate on the wound bed and as a result maceration is prevented. The PLA fibre reinforcement also enhances the integrity of the dressing and minimises the contamination of the wounds due to loose fibres and provides enough mechanical strength for painless dressing removal. The results also demonstrate that collagen boosters treated dressings maintain the wound bed in an acidic pH condition which also improves the wound healing process. In addition to the above stated properties, the collagen booster treatment imparts antimicrobial activity against Gram-positive and Gram-negative bacteria, thus resulting in the reduction in the propensity for wound infection.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Ultimately, the research has proved that the 4% collagen booster treatment enhances the antimicrobial activity and the acidic pH characteristics of the developed CMC/PLA composite wound dressings.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Introduction<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The wound healing is influenced by both intrinsic and extrinsic factors. There is a considerable global variation in the treatment of acute and chronic wounds; therefore, establishing a standardised, best way to manage wounds may not be possible.<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">Complete wound healing, which includes restoration of function, is hardly ever achieved in those disfigured by wounds especially when one includes the appearance of the skin or absence of an appendage (1; 2; 3). The wound maceration (pooling) usually describes the results of excess and retention of moisture, which can delay the wound healing.<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The wound desiccation can also delay the wound healing. An optimal moist environment is crucial for wound healing process. Comprehensive wound assessment, which includes wound classification, colour, depth, shape, size, amount of exudate, wound location, and the environment of care will all influence the choice of the wound dressing (4). The dressings can achieve the maximum absorption when they are applied on heavily exudating wounds. The optimum level of moisture has to be provided for reducing the wound healing time, conversely, the high levels of exudate combined with the pro-inflammatory mediators result in a detrimental effect on healing, including wound enlargement and damage to the periwound skin such as maceration and excoriation. It has been shown that when the wound exudate is absorbed and retained by the dressing, the maceration has been decreased (5). However the dressing will make sure that pooling of exudate cannot take place at one point.<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">In other words, enhanced lateral wicking will minimise the pooling of exudate at one point. The basic requirements of wound management are maintaining a moist environment at the wound surface and the removal of excess fluid from wound skin to prevent maceration or erosion of the wounds. The ability of a dressing to manage exudate and prevent maceration during healing is one of the most desirable properties for the cavity wound dressings (6). It is established that maceration causes wound infection and the wound infection can delay the wound healing (7).<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">It has been demonstrated that pH has an essential role to play during the healing process and an acidic environment is more beneficial for the wound healing process (8; 9; 10). The pH value within the wound environment directly and indirectly influences all of the biochemical reactions that take place during the healing process.<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The pH value is also a key determinant for the metabolism during wound healing and, therefore, is an important parameter for therapeutic interventions in woundcare due to pH and biochemical reaction speed interaction (9). Decreasing pH value of the wound surface is one of the essential requirements of the wound dressing material, although there has not been much research into this interaction. In previous studies, acetic acid in 1% and 5% solutions has been applied as a topical agent to reduce the pH of the wound surface (11; 12). Using acetic acid to reduce the pH was not an effective method, as the acetic acid can only decrease the pH for 1-hour period and, after that, the wound pH returns to the untreated pH value (13).<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">Another problem with using acetic acid is its availability; there is now no licensed sterile acetic acid agent for use in wound management (14). The innovative aspects of this study principally consist of: a) developing suitable structures by using appropriate fibres for wound management; b) selection and optimisation of collagen boosting chemicals to enhance wound healing; c) integration of collagen boosters into the optimised textile structures that contain different composites; and d) testing and characterisation of collagen booster treated novel composites. The CMC and PLA fibres combination was chosen for this study. The developed novel composite dressing consists of two layers, the first layer is of CMC fibres which absorbs high amount of wound fluid and the second layer is of PLA fibres which diffuses the absorbed fluid around the wound dressing. The developed CMC/PLA composite wound dressing was treated with 4% collagen booster (CB) solution.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Materials and Methods<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></strong></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The carboxymethylcellulose (CMC) staple fibres were kindly supplied by ConvaTec, UK. Polylactic acid (PLA) fibres were kindly provided by Dorte Logemann, Bremen, <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Germany. The properties of the above fibres were tested and analysed (Table 1).</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">Prior to producing nonwoven structures, the fibres were conditioned for 48 hours in <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">65 ±2% relative humidity and 20±2°C temperature. The fibre linear density values </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">were determined by using Vibromat M Tester (Textechno Company, Germany).</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The single-fibre CMC, 75/25% CMC/PLA and 50/50% CMC/PLA composite fabrics <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">were produced by using the Automatex Laboratory Nonwoven Line, Nuova </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Automatex, Italy at the University of Bolton and their absorbency, wicking, pH and antibacterial activity were tested and analysed. Two different collagen boosting (CB) agents were blended with ratio of 3% (w/v) CB-1 and 1% (w/v) CB-2. This 4% CB solution was prepared by dissolving powders with a magnetic stirrer in 1% (w/v) acetic acid solution until the solution turns to transparent. The 4% CB solution temperature was 50<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">o</span>C during the solution formation. The mixture was stirred for 30 minutes at this temperature. After complete dissolution, the solution had varying pH values from 4.0 to 5.0. The solution treatment of fabrics was done mainly by the spray coating technique at the room temperature. The test solution A, which was prepared by dissolving 2.298g sodium chloride and 0.368g calcium chloride </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">dihydrate in 1 litre of distilled water, was used to simulate serum and wound fluid.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 1" height="134" src="http://www.wtin.com/media/16082/table-1.jpg" style="border: 0px; display: block; line-height: normal; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="455" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Results and Discussion<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The area density, thickness and bulk density of the fabrics are given in Table 2.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">According to Table 2, the area densities of untreated fabrics were found to be much higher than the coated fabrics. The thickness of fabrics ranged from 3.6 mm to 4.4 mm. The most obvious finding to emerge from the physical characterisation of the <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">fabrics is that the fabric properties were affected by the spray coating process.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 2" height="318" src="http://www.wtin.com/media/16083/table-2_740x318.jpg" style="border: 0px; display: block; line-height: normal; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="740" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: normal; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Absorbency and wicking properties</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;"><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The absorbency, vertical and lateral wicking, and the rate of absorption results are shown in Table 3. It was observed that 50/50% CMC/PLA fabric had the lowest </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">absorbency value with 75/25% CMC/PLA fabric showing a better absorbency value.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">This study confirms that PLA containing fabric had somewhat decreased absorbency as compared to single-fibre CMC fabric. On the other hand, PLA fibres helped to increase the vertical and lateral wicking properties significantly, which is one of the most important objectives of this research work. It is also worth mentioning that the treatment did not affect other properties tested considerably. The wicking properties of the single-fibre CMC dressing have been enhanced by using PLA fibre reinforcement. This will help in stopping the pooling of the exudate in one specific area of the wound dressing. The enhanced wicking can reduce the risk of maceration.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 3" height="311" src="http://www.wtin.com/media/16084/table-3_734x311.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="734" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: normal; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">pH and antimicrobial properties of treated fabrics</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The mean values from day 1 to day 7 for each fabric in solution A are given in Table <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">4. In all cases, the pH values of solution A decreased with the immersion of fabrics in it. The pH value of treated fabric immersed in solution A gradually decreased over time. The most important result to emerge from the data is that 4% solution treated fabrics had considerably lower pH value as compared to their untreated counterparts. It can be concluded from these results that the 4% solution treatment can provide the desired acidic pH of ≤ 4.0 which helps to enhance the wound healing process.</span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 4" height="326" src="http://www.wtin.com/media/16085/table-4_739x326.jpg" style="border: 0px; display: block; line-height: normal; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="739" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;"><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The Staphylococcus aureus bacteria at 10-1 dilution and the Escherichia coli bacteria at 10-3 dilution were studied to determine the antibacterial activity of 4% CB treated fabrics. The zone of inhibition values are tabulated in Table 4 and are depicted in Figure 1. The untreated fabrics did not show any zone of inhibition. It is clear from Figure 1 that all 4% CB treated fabrics demonstrate promising zone </span><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">of inhibition. It can thus be concluded that the blend of collagen boosting agents at acidic pH can be effectively employed for achieving the antibacterial activity of the developed wound dressings which is one of the main objectives of this study. </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Figure 1" height="500" src="http://www.wtin.com/media/16087/figure-1_740x500.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="740" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="background-color: #f3f3f3; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Conclusions<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">The overall functional properties of the single-fibre CMC dressing have been enhanced by using PLA reinforcement. The enhanced wicking can reduce the risk of maceration and infection. It needs to be stressed that the PLA reinforcement has not influenced the higher absorbency properties of the CMC dressings considerably. The <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">CMC/PLA dressing still has a higher absorbency than alginate dressing (15), which is one of the well-known high absorbent wound dressings. The developed PLA containing novel dressing possesses the desired fluid absorption and wicking properties which make the PLA fibres an ideal reinforcement to be incorporated into </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">the CMC fibres. The incorporation of PLA fibres in composite structures for wound dressing application can also be considered as an ecologically friendly combination mainly because of easy biodegradability. In addition, PLA fibres provide biocompatibility, non-toxic, high absorption and wicking properties. </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">After achieving the intended major structural properties, the developed novel </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">CMC/PLA composite structures were treated with collagen boosting agents.</span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">One of the major objectives of this research paper was to incorporate suitable collagenboosting agents onto the novel composite dressings. Two different collagen boosting agents have been successfully applied on the developed fabrics. The results suggest that 4 % CB (w/v) solution can produce the desirable attributes in the wound dressings. The 4% (w/v) collagen boosting solution treated fabrics exhibit the desired properties related to the acidic pH and antibacterial performance. The two major objectives of the study have been successfully achieved by collagen booster agents, one collagen booster provides acidic pH and the other provides antibacterial property. The two collagen boosters, contained in 4% solution, treated dressings delivered desired acidic pH and antibacterial in addition to enhancing the growth of collagen during wound healing. In general, these findings have important implications for developing ‘all-in-one’ therapeutic nonwoven wound dressings.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">Finally, the best combination for achieving the desired properties have been observed from the 4% (w/v) collagen boosting solution treated 75/25% CMC/PLA composite dressing. The findings of this study have a number of important implications for future practices in wound care; however, the in vitro observations need to be supported and confirmed by in vivo and clinical evaluations.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">References</span></strong><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">1. Krasner, D.L., Rodeheaver, G.T. and Sibbald, R.G. Chronic Wound Care: A <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Clinical Source Book for Healthcare Professionals (4th edn). New Jersey : HMP </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Communications, 2007.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">2. Macdonald, J.M. and Geyer, M.J. Wound and Lymphoedema Management. s.l.:<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">World Health Organization, 2010. ISBN 978 92 4 1599139.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">3. Gethin, G. The significance of surface pH in chronic wounds. Wounds UK. 2007, <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Vol. 3, 3, pp. 52-54.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">4. Ovington, L.G., Pierce, B. and Wayne, K. Wound dressings: form, function, <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">feasibility, and facts, Chronic wound care: A clinical Sourcebook for Healthcare </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Professionals. London : Health Management Publications Inc, 2001. pp. 311-319.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">5. Sharp, C. Managing the Wound with Hydration Response Technology. Wound <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">UK. 2010, Vol. 6, pp. 112-115.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">6. Thomas, S. Exudate-Handling Mechanism of the Cutimed Cavity Range of Foam <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Dressings: Laboratory Report 2. London : BSN Medical: www.medetec.co.uk, 2009.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">7. Seo, S.Y., et al. Alginate-based composite sponge containing silver nanoparticles <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">synthesized in situ. Carbohydrate Polymers. 2012, Vol. 90, pp. 109-115. </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">8. Tsukada, K., et al. The pH changes of pressure ulcers related to the healing <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">process of wounds. Wounds. 1992, Vol. 4, 1, pp. 16-20.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">9. Schneider, L.A., Korber, A. and Grabbe, S.Dissemond, J. Influence of pH on <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">wound-healing: a new perspective for wound-therapy? Arch Dermatol Res. 2007, </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Vol. 298, 9, pp. 413-420.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">10. Schreml, S., et al. Wound healing In the 21st century. J Acad Dermatol. 2010, <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Vol. 63, 5, pp. 866-880.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">11. Leveen, H., et al. Chemical acidification of wounds. An adjuvant to healing and <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">the unfavourable action of alkalinity and ammonia. Ann Surgery. 1973, Vol. 178, 6, </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">pp. 745-750.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">12. Leung, D., et al. Use of distilled white vinegar dressing supplement to oral <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">antibiotics in the management of Pseudomonas aeruginosa exit site infection in </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">continues ambulatory peritoneal dialysis patient. Hong Kong J Nephrology. 2001, </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Vol. 3, 1, pp. 38-40.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">13. Milner, S.M. Acetic acid to treat Pseudomonas aeruginosa in superficial wounds <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">and burns. Lancet. 1992, Vol. 4, 3, pp. 340-361.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">14. Poulter, N., et al. Plasma deposited metal Schiff-base compounds as <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">antimicrobials. New J Chemst. 2011, 7.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: #f3f3f3;">15. Uzun, M., Anand, S.C., Shah T., Study of the pH and Physical Performance <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Characteristics of Silver Treated Absorbent Wound Dressings” Journal of Industrial </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Textiles, 2012: DOI: 10.1177/1528083711435183.</span></span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-32126119989907177942014-06-09T00:24:00.000-07:002017-03-01T03:24:34.648-08:00Transforming Textile Printing<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In our recent InfoTrends study called ‘Transforming Textile Printing’ our team took an in-depth look at opportunities for digital printing in the textile market. The potential for digital printing to influence the printed-textile market has long been promised, yet less than 1.5% of printed textiles are digitally printed today.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The textile market is a vast business, easily surpassing $1 trillion in annual revenue on a worldwide basis. Encapsulated in this number is the ‘printed’ textile volume, which is more than $165 billion, and yet nested within that is a digital-textile printing segment which InfoTrends believes is valued at more than $10 billion worldwide.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The global nature of this market is extremely important, because the textile business is critical to some of the world’s largest and fastest growing economies. In fact, adoption of digital-textile printing systems is a global phenomenon, as none of the major printed-textile regions can afford to be left behind in terms of their ability to meet the changing demands of the market. The market is led by the Europeans, where many of the top fashion centres and leading brands reside, but there are growing markets for digital-textile printing systems worldwide. What we learned as a result of this study is that changing <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">dynamics in brand management, as well as retail go-to-market, </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">present an enormous potential for high-speed digital textile </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">printing systems over and beyond the forecast period. These </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">changes include: increasing number of fashion seasons and t</span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">he resulting demand for faster cycle times; a trend to shorter </span><span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">run lengths; and the desire to mitigate risks for unused/unsold textile-based products.</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="2102 Digital Textile" height="209" src="http://www.wtin.com/media/15761/2102-digital-textile.jpg" style="border: 0px; display: block; line-height: normal; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="387" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">At the same time, on the technology side, there has been a generational leap forward with the recent introduction of high-speed systems that are more competitive with screen and gravure textile printing both in terms of production speeds and costs. The use of high-quality, high-speed inkjet print-head technology in these high-end systems enables production of hundreds, and even thousands of square metres per hour that are robust enough to run 24 hours a day, 7 days a week.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The combination of all of these factors will lead to a rapid adoption of digital-textile printing systems. InfoTrends is forecasting an overall compound annual growth rate of more than 28%, and more than 42% among the production-oriented high-end digital-textile printing systems.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="2102 Shipments" height="225" src="http://www.wtin.com/media/15762/2102-shipments.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="385" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This confluence of factors is driving change in the textile market and is expected to drive investment in digital-textile printing systems and usage through the present forecast period. The increasing ability of textile producers to respond to demand for faster cycle times is provided by digital printing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">While many traditional textile-printing companies are adopting digital printing, the developments cited in this InfoTrends research also have enabled the emergence of web-based companies, which specialise in short-run digital-textile production and provide these services to global businesses and consumers by employing digital-textile production workflows that are more efficient and faster than the traditional textile supply chain could offer.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-76183699769589584462014-06-09T00:23:00.000-07:002017-03-01T03:24:34.713-08:00ANALYSIS: Efficient workflow in digital textile printing<div dir="ltr" style="text-align: left;" trbidi="on"><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhECtaDMNBtFSIvbQUDtu9Svge_3xDA15Hzl-uyq2KvV2WqnUgOLV8vbZ5Ep6eiwZFQO7lhUxkYQhnpHQ5h8qsPD1cqsSHw6wnJqs6m8yXflguhKsg-eTbCF7z26X8pTc7IrinoqEbtOLY/s1600/Print_heads_compared_-_more_nozzles_in_bigger_print_heads_enables_higher_speeds.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhECtaDMNBtFSIvbQUDtu9Svge_3xDA15Hzl-uyq2KvV2WqnUgOLV8vbZ5Ep6eiwZFQO7lhUxkYQhnpHQ5h8qsPD1cqsSHw6wnJqs6m8yXflguhKsg-eTbCF7z26X8pTc7IrinoqEbtOLY/s1600/Print_heads_compared_-_more_nozzles_in_bigger_print_heads_enables_higher_speeds.jpg" height="237" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Digital workflows are not new and, in the wide-format inkjet industry in general, users work with different types of equipment, various profiles and RIP procedures, plus a wide range of media on the jobs they produce.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">There is a learning curve for every print-service provider or display specialist when making the move to textile printing, but confusion arises because of the perceived workflow complexity and the way in which some machine manufacturers tend to over-simplify the methodology needed. With the right guidance, however, it is not that difficult to achieve a profitable and efficient workflow in digital textile printing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Economics vs. Capacity</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In visual communication, soft signage for retail and branding is increasing its influence thanks to improvements in both quality and speed. New print heads, ink formulations and fabrics have been the base for a growth in direct-to-textile printing. Here, too, nozzle count has increased and speed has gone up.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">But, regardless of the specific market, speed in itself doesn’t count for much if the process is not offering the right economic model. In the end, it has to be commercially feasible to invest in a system that enables making a margin on the sales of the end product coming out of the factory.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The economic model of any printer relates to the cost of investment, running cost, going down to cost per square metre, and finally, to the profit per square metre. Speed isn’t in this equation; neither is relative quality. Speed may be achieved by either laying down less ink in fewer numbers of passes, resulting in lower quality, or by adding more print-heads, resulting in the need for more nozzles to jet the required ink volume on the fabric.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The greater the number of nozzles, the higher the initial purchase price of the printer. And, even though the higher speed may seem to be the biggest denominator for a purchase decision, it all comes down to the capacity and throughput expectations of the company making the investment. There is no financial benefit in having too much capability without a return on investment, regardless of print speed per hour.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It is not only the maximum amount of printed media in an hour that counts, although many print-shop owners and printer manufacturers alike focus on this single parameter; it is the total throughput as an end-product which must be assessed. This applies on a per-job basis as well as the average square metres generated from start to finish in any given time.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">With variable applications and fast job change-over being paramount reasons for adopting digital inkjet printing, the time and cost savings are generated by consistency in machine performance and in the set-up and use of all equipment on the shop floor. This is particularly relevant when it concerns printing on to textile; most of the time, another process follows the printing, which is only one aspect of the entire workflow. As such, a focus just on print speed omits the more important balance between economics and capacity.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Ignored Potential</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In some cases, lack of cohesion is forgivable and understandable because the print-shop owner literally grew into the situation of having different types of equipment over time or as a legacy. A quick assessment shows that some machines or operators are standing still and idly waiting for another process to finish before they can run the next step of the production flow. Additionally, because of incompatible systems, considerable amounts of time can be wasted on converting or changing media, rolls or processes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Another common problem concerns the colour reproduction and matching across systems. An issue often mentioned is the inability to catch mistakes before they happen. Operators who have grown to accept a certain system or method might be stuck with what they are accustomed to, and never research new or better options that can lead to greater efficiency and improved workflow overall.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Logically, running different types of machinery will cause variations in output. Different inks produce a different colour gamut, and different media will have had different treatments. Different print processes feature different resolutions and inkdroplet shapes and sizes. Some inherent differences can’t be circumvented but, in pursuing optimisation, there is a key factor that can greatly improve end results.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In a single print shop, many manufacturers and suppliers will have delivered equipment with their own methodology and their own ideas on how to approach a production flow. If one supplier suggests optimising a specific machine in a certain way to get better results, this can result in adverse effects along the way with other processes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">An example of this is a material that is developed with a coating for dye-sub transfer used in a calender heat-press system; it may not be suited for vibrant output when printing disperse direct ink and fixating it with an infra-red system. While one production method can work well, in another it might result in lower quality or, worse, slow down overall production.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Manufacturers and suppliers can be criticised justly for not providing adequate advice to their potential customers, who react typically by deciding not to invest in a technology because it appears to be too complicated or too different from what they already have installed. Similarly, although there are print-service providers working with digital textile, they are often not educating their specifiers – end customers, designers, agencies and brand owners – about the additional potential of using fabrics. An optimised workflow and an investment in a seamless production process can enable hitherto unconsidered opportunities to increase margin and provide new end products.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Learning Curve</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The key principles employed in digital-textile printing require a learning curve and investment, yet this is a practical step so that anyone can generate innovative fabric alternatives that supersede conventionally output counterparts. This type of production also results in higher quality, higher margins and higher uptime, particularly if workflow is optimised.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Workflow is surprisingly competent with digital-textile systems but there is a myth surrounding its efficacy and the way in which overall efficiency is quantified purely in terms of the speed of the actual printing device. Instead, other elements need to be taken into account when assessing a true throughput rate, including logistics, manageability and, of course, the number of operators on the print-shop floor.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For the majority of inkjet technologies in use today, each element is independent from the next, so that the printing machines and finishing stations are not related by manufacturer. And, even where one supplier provides a bundle or combination, it is often based on equipment coming from different sources. This means a slightly different machine width and media-handling technique, a varied approach to optimising speeds or developing interfaces and no relation between what happens at the beginning of the process and what can influence it at the end. It doesn’t mean that any single component is bad in itself, but the combination makes it less efficient.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It would be encouraging to know that equipment can effectively be put in one production flow without too many disturbances. For example, were the media-handling system to be the same across different machines, then it would be straightforward to load 2.3m media on a 3.2m-wide machine, as the handling is familiar, logical and fast. Likewise, being able to adjust ink volume precisely at the artwork-processing stage, to optimise the parameters that are essential for efficient printing, fixation, wash-off and media penetration, results in a more competent system. When all elements come from one dedicated manufacturer, with an eye for the details in the overall development, the combined compatibility should eradicate any problems when setting up a production workflow.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This type of set-up, where individual units come together to make a total system, means that operators can add to overall productivity by planning each job within set parameters. They know that their workflow is tailored to the solutions being used and the people who are using them, without unwanted or unexpected interference or disruption.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Good workflow also involves generating efficient practices across all production areas. Many of these might appear to be based on common sense, but this approach normally only becomes apparent when a system manufacturer is aware of all the processes involved in daily working, from start to finish.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In an ideal world, a truly efficient and reliable workflow needs to be based on compatible elements which, together, provide seamless production in a harmonious environment. There would be no nasty surprises likely to spring up from any part of the processing procedure, from file generation, colour management, printing and finishing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Particularly in the area of textile printing, application-driven solutions offer tailor-made processes which are beneficial in specialised production environments such as working with fabrics for soft signs, flags, banners, garments, décor and industrial end products. System efficiency and ergonomics also play a vital part in the economics and logistics of running an effective production line. Similarly, true compatibility between software, printing, fixation, washing and finishing ensures that a 24/7 operation flows smoothly and economically.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">As witnessed in the past few years, the markets for digitaltextile printing include sampling and proofing, outdoor and indoor advertising, retail and point-of-sale, plus in-store and commercial and residential decoration. Industrial applications include transport and clothing, and commercial and domestic applications offer tremendous potential for fabrics.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A manufacturer that typically focuses on converting an existing print engine, so that it can be used to print on to textile, doesn’t take all these application examples into account or put them into the right context of making sure that the fabric and the machine work together in precise harmony. Just as often a standard is set from limitations, and not from possibilities, which leaves the agency, the brand owner, the designer and the print-service provider with a misunderstanding about potential and capabilities.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This poses an interesting question, albeit based on rhetoric. Is print speed still the most important factor when concerning the overall production process? For instance, if an in-line fixation process limits print speeds, the maximum throughput rate might not count for much. If loading media or preparing and RIPping artwork for print is slowing down the printing process, how does that relate to the overall production speed? The obvious, and practical, answer is that workflow efficiency does not come from print speed alone.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-64088799325340434062014-06-09T00:18:00.000-07:002017-03-01T03:24:34.683-08:00TECHNICAL FEATURE: Eco-friendly dyeing of silk with Croton<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Abstract</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The great appeal of textiles lies in their colours and the way that colour is used to create patterned effects. Colour is applied by the process of dyeing, which in its simplest form involves the immersion of a fabric in a solution of a dyestuff in water.</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjiDGzJsHz0umLcZb_397fsj2B6mPVuqMS7jhcdHodTJqIpGU7brlHubgMFOHRH-nvFACK9Uh7-DoAUuhiGsqTlqN3bAAzGABF6jO-hk1EHj9nDSxsjxKfMbyoanl16e1n8fXZtOG_YMNY/s1600/ID_1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjiDGzJsHz0umLcZb_397fsj2B6mPVuqMS7jhcdHodTJqIpGU7brlHubgMFOHRH-nvFACK9Uh7-DoAUuhiGsqTlqN3bAAzGABF6jO-hk1EHj9nDSxsjxKfMbyoanl16e1n8fXZtOG_YMNY/s1600/ID_1.jpg" height="170" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The amount of dyestuff required is very small, but its production and application require considerable skill. Changes in the ways of producing dyes during the nineteenth century heralded modern science. The uses of natural dye on textile materials are now being popularised globally by the continuous efforts of nature lovers. The problems caused by synthetic dye in human lives and environments, since the introduction of synthetic dye more than a century ago, has come to an alarming level today. Hence there is an urgent need to for an alternative to the hazards of synthetic dyes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">To explore the use of natural dyes is one such immediate solution. However, the limitations with the natural dye are their poor fastness properties, limited shades, low brilliancy, etc. To some extent, adding selected mordants/chemicals in natural dyeing is accepted, provided the character of the natural dye is unaltered and the eco-system is not damaged.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The present study explored the development of a process for the extraction of natural dyes from abundantly occurring plants, flowers namely Croton (Croton species) leaves. The study showed that this source can produce different shades of brown and peach colour. A series of experiments was conducted to optimise the different variables for dyeing. Acidic medium was optimised for dye extraction. For Croton dye, 8% dye concentration, 60 minutes extraction time and 75 minutes dyeing time were optimised.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Test of colour fastness to light, washing, perspiration and crocking were also carried out. The results concluded that the light fastness, washing, fastness, perspiration and crocking fastness of the Croton dye were good and samples that were mordanted showed better fastness properties as compared to control. This dye source is abundantly available throughout the year and does not cause environmental depletion. Experiments proved that the Croton dye is the good source for dyeing silk in shades of brown and peach. Thus it can be concluded that this dye has a lot of commercial potential.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Introduction </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The use of natural dyes has attracted increasing worldwide attention as the carcinogenicity and environmental pollution problem of synthetic pigments are becomes a great concern.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Increased environmental awareness and health hazards associated with the use of synthetic dyes have led to the revival of natural dyes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Natural dyes are eco-friendly and promote the green revolution. It is the need of the day to exploit the forest wealth that can be a source of colour for textiles.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Natural dyes are deep and soft in colour, and many of these have antibacterial, insecticidal and medicinal properties, due to their natural origin, from herbal plants. Most of the natural dyes are non-substantive dyes, as they require the aid of mordants to penetrate the yarn/fibres.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Croton (Croton species) leaves come from one of the most colourful evergreen shrubs that we grow indoors. Also known as Codiaeum, this plant has its origin in Malaysia and the larger islands in the West Pacific. It is grown for its decorative foliage. The leaves are alternate, linear to broadly ovate, simple or shallowly to deeply lobed, and often variegated. They reach all the possible colours that a leaf can be, from the brightest green and yellow to the deepest green and red. Foliage colours change as the plant matures. There are never two leaves that look the same on a plant, and this is why Croton is so attractive.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In the present era the revival of natural dyes has created opportunities for researcher to explore for alternative sources that can compete with synthetic dyes in brilliant colour fastness.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Keeping these points in mind, an attempt was made through this study to optimise various dyeing variables for dyeing of silk fabric with Croton dye and also to test the colour fastness of dyed samples.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Experimental Procedure</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Selection of Fabric</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Silk (garad) fabric was selected for the study, as this fabric gave brilliant shades with selected dyes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Pretreatment of Silk</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A mild detergent (genteel) solution containing 0.5 ml of genteel/100 ml of water was prepared and heated to 50°C. Silk fabric was dipped in to this solution and stirred gently for about 30 min, then it was rinsed under tap water and dried in shade and ironed when half wet.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Selection of Dye</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Croton (Croton species) leaves were selected for the study. The leaves were dried in shade.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Selection of Mordants</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Three metallic mordants, viz. potassium aluminium sulphate (alum), copper sulphate and ferrous sulphate, and three natural mordants, namely bahera, pomegranate rind and tea leaves, were taken for study.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For each mordant, four concentrations – ie.0.5, 0.10, 0.15 and 0.20gm for alum; 0.1, 0.2, 0.3 and 0.4gm for copper sulphate and ferrous sulphate; and 1, 2, 3 and 4gm for bahera, pomegranate rind and tea leaves – were used. Three methods of mordanting, viz. pre-, simultaneous and post-mordanting were used for the study.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Optimisation of Dyeing Variables</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A series of following experiments were conducted to determine the dyeing variables such as extraction medium, optimum concentration of dye material, extraction time, and dyeing time, concentration of mordants and methods of mordanting.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Medium of Extraction for Dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dye from Croton was extracted in alkaline, acidic and aqueous medium. Acidic medium was prepared by adding 1ml of hydrochloric acid in 100ml of water and alkaline medium was prepared by adding 1gm of sodium carbonate in 100ml of water. The dye material was then entered in each solution and boiled at 60°C for 1 hour. For aqueous medium only dye material was added in 100ml of water. To each dye extract, a known amount of silk fabric introduced and dyeing was carried out for 60 minutes. The method that gave the best colour on the silk was selected for further study.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Concentration of Dye Material</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Five different concentration of dye material were prepared separately by heating 2, 4, 6, 8 and10gm of dye material in 100ml of water at 80°C for 1 hour. The solution were filtered and cooled.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The optical density (OD) of the dye solution before and after dyeing was recorded and the percent absorption was calculated by using following formula:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Percent absorption = Optical density before dyeing - optical density after dyeing/Optical density before dyeing X100</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The concentration that showed the highest percent absorption was selected as the optimum concentration for further study.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Time for Extraction of Dye</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The selected concentration of dye material was taken in five beakers, each containing 100ml of acidic water and boiled for 30, 45, 60, 75 and 90min respectively. To each extracted solution, known weights of silk fabric were introduced and dyed for 60 minutes. The dyed fabrics were removed from the dye liquor, and dried in shade. Percent absorption was calculated for each sample and, on the basis of results, time for dye extraction was optimised.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dyeing Time</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Five dye solutions of Croton leaves were prepared by extracting dye using the optimum dye concentration and extraction time in 100ml of water. Dyeing of pre-soaked silk samples was carried out for 30, 45, 60, 75 and 90 minutes respectively.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Percent absorption by each sample at different dying times was calculated. Based on maximum percent absorption, the best dying time was optimised.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Preparation of Blank Sample</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">After optimising the dying variables, a known amount of silk fabric was dyed with the optimum concentration of dye, extraction time and dying time.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Colour Fastness Testing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Each dyed sample was tested for colour fastness against light, washing, rubbing and perspiration. Light fastness testing was carried out according to the ISI: 971-1156 Test method; the washing fastness test was carried out as per recommendations of ISI test no.3; fastness against rubbing was determined using AATCC test method; perspiration fastness testing was carried out according to ISI: 971-1156 test method.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Results and Discussion</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Medium of Extraction of Croton Dye</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Among three media of dye extraction, ie. acidic, alkaline and aqueous, acidic medium was selected as the best. Dye extracted with 1% hydrochloric acid was selected for dye extraction.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dye Concentration</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Silk fabric was dyed with five different concentrations of Croton dye, ie. 2, 4, 6, 8 and 10%. The maximum percent absorption was obtained with 8gm dye material/100ml of water/2gm of silk. Results are shown in Table 1.</span></div><div class="separator" style="clear: both; text-align: center;"></div><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhoSULTDSXC-Trew7_GoEHZbcPX7xg40UXICLSKB5n89GZNM93_uICiicMtT820vxceBIotRFlyBolNtceFN-bReUEcLYdqCB8wITvmtakpqquXPSCejEa-0qadG8LpemeDh6I2nxxXDLg/s1600/ID_2.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhoSULTDSXC-Trew7_GoEHZbcPX7xg40UXICLSKB5n89GZNM93_uICiicMtT820vxceBIotRFlyBolNtceFN-bReUEcLYdqCB8wITvmtakpqquXPSCejEa-0qadG8LpemeDh6I2nxxXDLg/s1600/ID_2.jpg" height="233" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dye Extraction and Dyeing Time</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The dye was extracted and dyed at 30, 45, 60, 75 and 90 min. Maximum percent absorption was obtained at 60 minutes for extraction and 75 minutes for dyeing. Therefore 60 and 75 minutes were selected as optimum for extraction and dyeing time respectively. Results are shown in Table 2.</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgo8Dq8LhiGLVO4edViMs10kyk0YDsZsTtJSoNQSDmYP02ECXht6pNzcnEsRtLbbXvAJdn86By7Q2R3GkmgW22RWG7go-ajFpdDjCekxHzPvG2ltomOoOEW1R-Wc16HlwR3WZ6PwhZOUiA/s1600/ID_3.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgo8Dq8LhiGLVO4edViMs10kyk0YDsZsTtJSoNQSDmYP02ECXht6pNzcnEsRtLbbXvAJdn86By7Q2R3GkmgW22RWG7go-ajFpdDjCekxHzPvG2ltomOoOEW1R-Wc16HlwR3WZ6PwhZOUiA/s1600/ID_3.jpg" height="234" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Concentration of Mordants</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Synthetic Mordants</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It was found that out of the various concentration of mordants used with Croton dye, best shades of colour were obtained by using 0.05gm (pre-mordanting), 0.10gm (simultaneous mordanting) and 0.15gm (post-mordanting) of alum; 0.02gm (premordanting), 0.01gm (simultaneous mordanting) and 0.04gm (post-mordanting) of copper sulphate; and 0.02gm (pre- and postmordanting) and 0.01gm (simultaneous mordanting) of ferrous sulphate.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Natural Mordants</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For Croton dye the concentration found best for different natural mordants were: bahera 01gm (pre-mordanting) and 03gm (simultaneous and post-mordanting); pomegranate rind 04gm (pre-mordanting), 01gm (simultaneous mordanting) and 04gm (post-mordanting); and tea leaves, 02gm (pre-mordanting and simultaneous mordanting) and 01gm (post-mordanting). (Table 3)</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjnCP4u75GQXx68ia3iMlEsGGNkWMZ4D_Yg7lFQnDOIBlfIDs5RP_Xq9fFDadYe_hUihOQ3u0M3rP8RQGRJSS0eTsbdF_E2Euspp2HzjGVv5gxa_3WaPHhUlvIKWz_4tJpkhHHw-sQUU9A/s1600/ID_4.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjnCP4u75GQXx68ia3iMlEsGGNkWMZ4D_Yg7lFQnDOIBlfIDs5RP_Xq9fFDadYe_hUihOQ3u0M3rP8RQGRJSS0eTsbdF_E2Euspp2HzjGVv5gxa_3WaPHhUlvIKWz_4tJpkhHHw-sQUU9A/s1600/ID_4.jpg" height="320" width="210" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Colour Fastness</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Colour fastness grades of silk samples dyed with Croton dye using different concentration of each mordants and three mordanting methods are given in Table 4.</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiSnqaQ8B1tiNvtNCMLzBeq2Elv0WHNYGUBnRpN3D_MRK1g_GN_938bzrcaqinaJiQtR4J5-KLiebMl9_nKbm5dlVXbZCQ2s0wu_PXobCQMx1K5BQV-LemIVNhB2Qo_JNYvDsIx5moMifY/s1600/ID_5.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiSnqaQ8B1tiNvtNCMLzBeq2Elv0WHNYGUBnRpN3D_MRK1g_GN_938bzrcaqinaJiQtR4J5-KLiebMl9_nKbm5dlVXbZCQ2s0wu_PXobCQMx1K5BQV-LemIVNhB2Qo_JNYvDsIx5moMifY/s1600/ID_5.jpg" height="216" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> The results given in the table reveal that the light-fastness grade ranged between poor (2) and good (5).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Washing fastness tests revealed that silk samples dyed with Croton dye showed considerable to slight colour change (2-4) and slight to no staining (4-5). Colour fastness grades were maximum in the case of all mordants. Ferrous sulphate and tea leaves gave better washing fastness.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Perspiration fastness grades for all the mordants were showed slight to negligible colour change (4-5) in acidic medium, whereas considerable to slight change (2-4) in colour was found in alkaline medium. Metallic mordants showed better perspiration fastness than natural mordants.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In crocking fastness, it was found that wet crocking ranged from slight to no staining (4-5) for samples mordanted with metallic mordants. In the case of natural mordants it ranged from noticeable to no staining (3-5). There was no change in colour in both dry and wet crocking.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Conclusion</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Croton dye is a good source of pinkish brown (peach) colour and it creates a number of fast shades, ranging from brown, grey, green and khaki, on silk by using different natural and metallic mordants.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Researchers and scientists have a good opportunity to make a pollution-free environment by using this source on textile material, as the processing of these dyes involved no toxic chemical.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A wide range of colours and satisfactory fastness to light, washing, perspiration and crocking were obtained on silk.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Finally, it can be concluded that the application of Croton-leaf dye for dying of silk can be considered as an effective eco-option for protection of our environment and can be commercialised.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">References</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">1. Bello, K.A and Defeng, Z.1999 Dye and intermediate. The Indian Textile journal 10(10) : 42</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">2. Das, S. 1992. Application of natural dye on silk, Colourage, 32 (9) 152</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">3. Gulrajani M.L 1993 Mordant compendium of inter regional workshop on natural dyes. Lucknow NHDC Ltd; pp 96-103.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">4. Patra, S.K.; Nayak, A. and Das, N.B.2000. Yellow dye from debarked jack fruit wood. Colourage, 17 (8): 17</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">5. Paliwal, J. 2001. Effects of mordants on henna dyed cotton and silk fabric. Textile Magazine, 42 (11): 79.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">http://www.chemistryexplained.com/Di-Fa/Dyes.html</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">http://houseplants-care.blogspot.com/2006/05/ croton-plant-care.html</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-70429757531716313742014-06-09T00:15:00.000-07:002017-03-01T03:24:34.690-08:00Innovations in knitting technology<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Stoll has applied for a patent for a knitted article, such as a cardigan or a pullover, which has a waist-band followed by a base fabric which contains a knitted pocket. The invention aims to alter the conventional pocket placing above the waistband in order to deepen the former substantially.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This is achieved by starting the knitted-in pocket part (4) in the waist-band (2) and extending the former into the main part of the garment (3), producing a deeper pocket to prevent stored items from falling out and to enable the wearer to put their hands into the enlarged pockets.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A distinctive knitting linkage of the pocket part is adapted in the waist-band region with regard to its appearance and elasticity. The patent application also includes an independent claim for a method of producing a knitted garment piece with a knitted-in pocket section.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: DE102008051993 Publication date: 22 April 2010 Applicant: Stoll</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Circular knitting</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patterning method</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - The German Research Institute, SIPRA has applied for a patent for a knitting machine with a newly designed needle cylinder to produce patterned knitted goods. The needle cylinder accommodates movable knitting elements which may be either latch or compound needles.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Cams can select needle butts to pass through one or another cam track in accordance with the pattern. The patterning device is designed so that in each selection step at least two knitting elements lying adjacent in the needle cylinder are simultaneously selected and controlled in one or other of the two cam tracks or the same cam track.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: WO2010066219 Publication date: 17 June 2010 Applicant: SIPRA</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Warp knitting</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Tension setting</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Karl Mayer has recently published three patent applications. The first is a device for tension setting of individual threads during the warping operation for a warp-beam. The operation involves winding the warp threads on to a warping drum under a predetermined tension. The invention aims to set the tension of the warp threads to the required level at low operational cost by using an energy back-feeding unit.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The break energy needed to set warp thread tension is not transferred into heat but fed back into a net or energy storage facility.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Fed back energy can be used to drive other machines or installations, whilst the reduction of heat makes it possible to carry out warping operations in halls which do not need expensive climatising plants.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The device has a rotary body partially wrapped by a yarn, where the former is connected to an electric machine which acts as a generator. This is connected to an energy recycling device, a four quadrant adjustor. The recycling device has a transformer, rectifier and multi-phase structure inverter and is connected to an energy supply device. An independent claim is also included for a warping device.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: EP2192072 (A1) Publication date: 2 June 2010 Applicant: Karl Mayer</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Knotting device</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Karl Mayer’s second patent application concerns a knotting device used during the warping process. Much conventional warping for warp knitting machines uses yarn package creels which can only hold a limited number of yarn packages. These are insufficient to supply threads for the warp’s full width so the warping process involves a great deal of knotting.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The invention aims to simplify the yarn change operation by combining the advantages of a manual knitting tool with those of a fully automatic knotter, which also saves cost. The knotting device (1) has a carrier (2) connected to a handle (3) for movement control by an operator.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A suction device (17) is provided on the chassis where a thread-catch mechanism (15) and a knotter (16) are arranged. A support unit (11) is mounted on the carrier where the thread catch mechanism and knotter are fitted in a height-adjustable manner. The operator pulls or pushes the carrier to individual knotting points on the creel and the yarn catch unit substantially shortens knotting time.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: EP2196424 Publication date: 16 June 2010 Applicant: Karl Mayer</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Needle-bar design</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - The third patent application by Karl Mayer concerns needlebar design for very fine gauge warp knitting machines. The invention facilitates use of filler elements in the needlebar between neighbouring needles.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Simply reducing needle thickness brings the danger that a warp knitting machine needle will lose its sideways stability, creating a risk that it will collide with the guidebar guides.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The arrangement has a needle-bar which contains tricks or grooves to accommodate, in a removable manner, a section of knitting needles. The filling elements are arranged between adjacent needles in the region between the holding and working-end needle sections. An independent claim is included for a method of forming the knitting needle arrangement.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: ES2341372 Publication date: 18 June 2010 Applicant: Karl Mayer</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Carbon fibre</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">China - Changzhou Diba Textile Machine company has applied for a patent concerning a multiple axial warp knitting machine for knitting carbon fibre.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The machine consists of a pan-head device, a head component, a head frontend working mechanism and a weft laying-in mechanism. The head component is connected between the head front-end working mechanism and a weft laying-in mechanism.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A weft laying-in frame is connected with a separation device, a press roller and a 0- degree warp delivery device of a 0-degree of a warpheating transition wherein the separation device contains carbon fibre stocks and release paper.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The press-roller is arranged between the separation device and the 0-degree warp heating transition roller device. The position of the pan-head device can be adjusted.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The invention has the advantage that carbon-fibre warps are fully widened, the fibres are laid on the warps and the latter are delivered into the machine head to be knitted in a smooth and clean way.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The technical configuration of the 0-degree warp knitting of carbon fibres is fully achieved and the defects which have occurred when using carbon fibre warp knitting machines in China are said to have disappeared.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: CN10166 0244 Publication date: 3 March 2010 Applicant: Changzhou Diba Textile Machine</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Support shaft</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Karl Mayer has recently applied for a patent concerning a warp knitting machine with a section containing at least one support shaft for levers for the knitting elements which is able to turn and is fixed in an axial direction.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The section of the machine also includes a patterning installation. The knitting elements (needles and warp thread guides), working together, have, depending on the machine gauge, little distance from each other. To prevent collision of needles and guides during knitting, precise positioning of knitting elements is essential.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">On conventional warp knitting machines it is necessary to support the shafts which promote movement of knitting elements by a number of frames within the machine frame, making it difficult to ensure precise positioning of the elements.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Furthermore, patterning facilities determining axial movement guide-bar guides extend the full width of the machine, whilst necessitating an additional machine frame.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The invention aims to increase precision of positioning of the support shafts of the knitting elements and to reduce the machine’s frame width.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: CH700191 Publication date: 15 July 2010 Applicant: Karl Mayer</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Hosiery knitting</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Hosiery machine</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Italy - Lonati has applied for a patent for a new circular knitting machine for producing hosiery articles. The machine has a needle cylinder with a vertical axis and multiple number of tricks on the cylinder for accommodating needles and a needle actuating element.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Each actuating element has one connecting element with a radially extractable, movable butt that engages the connecting element actuation cams which face the cylinder surface. The cams comprise at least one extraction cam or one retraction cam with a portion whose profile is inclined with respect to an ideal plane perpendicular to the cylinder axis.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The knitting machine comprises means for extracting the movable butt of the connecting elements and keeping the butts in an extracted position over the entire extension of the cam portion which has an inclined profile, namely the extraction-cam or the retraction-cam.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: US2010011816 Publication date: 3 June 2010 Applicant: Lonati</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Loop transfer</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Italy - Lonati has also applied for a patent for a needle for transferring loops to adjacent needles on circular knitting machines for producing hosiery articles. The new needle comprises a shank, the upper end of which has a latch pivoted to it in order to open and close the needle head.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The needle comprises one elastic element formed on the shank’s opposite sides below the latch. There are thus two receptacles, one for each side of the shank. An adjacent needle head can be inserted in each of the receptacles in order to transfer the loop from the knitting needle to the adjacent needle.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: US2010043498 Publication date: 25 February 2010 Applicant: Lonati</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Knitted garments</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Underwear method</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">France - Euralis has filed a patent for a knitted undergarment and manufacturing method (Fig 3). </span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEglPbP85S8TbTeMpX1wUx8CriWcDCQCtfMwpnSJa9dFteRUpVX-Te_-N4Bgn-scYLWx2D41L45u6qfpRzcIdHgPEHmOTMTs7sN2nd4FvWrjTeuhsUqRiLNQ_Nv7hRGopkXFvoKyGzeGx_M/s1600/articleImage-1262.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEglPbP85S8TbTeMpX1wUx8CriWcDCQCtfMwpnSJa9dFteRUpVX-Te_-N4Bgn-scYLWx2D41L45u6qfpRzcIdHgPEHmOTMTs7sN2nd4FvWrjTeuhsUqRiLNQ_Nv7hRGopkXFvoKyGzeGx_M/s1600/articleImage-1262.jpeg" height="320" width="175" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The underwear garment, e.g. panties, (1) has a body (2) which forms the main part and comprises an upper peripheral edge (3) and lateral peripheral edges (4, 5).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The body is knitted in a jersey structure. Bands (6, 7, 8) comprise longitudinal edges (9, 10) and are assembled at the body by a seam in a nonsuperimposed position, in which one of the longitudinal edges of the bands is greater than 5mm.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The bands are knitted from spandex. An independent claim is also included for a method for producing the underwear.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: EP2141347 (A1) Publication date: 13 January 2010 Applicant: Euralis</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Sport’s garment</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Switzerland - A Swiss inventor has recently applied for a patent for a pair of sport’s trousers. These have an airtight outer skin made of an elastic material and a distancing layer arranged under the outer layer, made of a knitted fabric using mono-filament yarns.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The sealing edges are produced by wrapping the outer skin over the knitted distancing layer. A vacuum tube is connected to a connection piece. A portable vacuum pump produces a medically and advantageously indexed negative differential pressure in relation to atmospheric pressure which extends into the article of clothing as a result of the distancing layer, knitted in an open-work structure.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The vacuum pump is fastened to a strip which can be worn on an operator’s shoulders or other appropriate position. The invention aims to produce a spacer garment that makes it possible to simplify overall design of the clothing and corresponding pump unit while simultaneously lowering the costs substantially.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: US2010145237 Publication date: 10 June 2010 Applicant: Egli Wendelin</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Crotch closure</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Czechoslovakia - A Czech inventor has applied for a patent for knitted articles such as briefs, knickers and tights including the body part and leg parts which are closed in the crotch area by extra courses in opposition (Fig 4).</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjV8o71IjW1NVjnpM-FYxeIXKFIjNfezcXImWP6ioyZWFn_QiP8wL0uIvoVyMyyrx4QJZLb4lRXa_n6Db_vBZ4zPIqrTAiHzx1htviel2KwS_lhHO30X42IXhtniL6oF4k4iP7BdUH2w2s/s1600/articleImage-1272.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjV8o71IjW1NVjnpM-FYxeIXKFIjNfezcXImWP6ioyZWFn_QiP8wL0uIvoVyMyyrx4QJZLb4lRXa_n6Db_vBZ4zPIqrTAiHzx1htviel2KwS_lhHO30X42IXhtniL6oF4k4iP7BdUH2w2s/s1600/articleImage-1272.jpeg" height="280" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> Extra courses are (7.1, 7.2, 7.3, 7.4), at least one of which is created in the direction of the top (V1, V2, V3, V4) at first by the extending part (7.1A, 7.2A, 7.3A, 7.4A) and then by the narrowing part (7.1B, 7.2B, 7.3B, 7.4B).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Using the method, briefs, knickers and tights are closed in the crotch area by at least one pair of opposite extra courses knitted by reversing runs. The extra courses for leg parts have their edge links of the extending part knitted together with the links of the last continuous line of the leg part. The extra body part courses, on the other hand, have the edge links in the extending parts knitted together with the links of the first continuous body part line.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: US2010132411 (A1) Publication date: 3 June 2010 Applicant: Ando Jan</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Ancillary</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Cam assembly</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Groz-Beckert has recently applied for a patent for a cam assembly part for a circular knitting machine set with slider needles (Fig 5).</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgEDwoFb527o_jwlMR0kjoID7SCVrEzE5jNFVEiuwCZpEB7LQFvLvawkyNhzCvwYsW_anouJvriqJ-QnU6Q66iQotPmpgi2L-Qj-xoxWXCYrNuEC17GHgapacicMxzYgH_Q-pkz6TIn0sI/s1600/articleImage-1282.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgEDwoFb527o_jwlMR0kjoID7SCVrEzE5jNFVEiuwCZpEB7LQFvLvawkyNhzCvwYsW_anouJvriqJ-QnU6Q66iQotPmpgi2L-Qj-xoxWXCYrNuEC17GHgapacicMxzYgH_Q-pkz6TIn0sI/s1600/articleImage-1282.jpeg" height="320" width="168" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The aim is to offer a new cam assembly to control slider butt movement. According to the patent application, the cam assembly can also be adapted for use on flat knitting machine carriages.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The invention allows adjustment of one cam assembly part (22) with respect to another (27) meaning timing of closing and opening of the slider needle hook inside can be adjusted relative to slider needle retraction timing and set as needed.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The invention aims to increase knitting quality and operational safety of a knitting machine set out with compound needles. When the invention is adapted for use on flat knitting machines set up with compound needles the knitting cam assembly path is linear.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: US2010147034 (Al) Publication date: 17 June 2010 Applicant: Groz-Beckert</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Thread guide</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Another new patent application filed by Groz-Beckert concerns a knitting machine without holding-down sinkers. Instead, the circular knitting machine has a thread-guide associated with a runner.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The runner holds open the latches of the rising needles of a first group, while needles of a second group are driven out. Due to time staggered driving out of the latch needles by way of a first and second group and alternating arrangement of the needle groups, rising of the cast off loops on the needle stems is prevented, making use of knock-over and holding down sinkers unnecessary. The runner, separate from the thread-guide, is used to hold open the needle latches and can be adjusted independently from the thread-guide position.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: US201014735 (A1) Publication date: 17 June 2010 Applicant: Groz-Beckert</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Needle monitoring</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Memminger has applied for a patent for a new method and apparatus for monitoring knitting machine needles. The invention is based on a system of optical supervision where individual signal impulses are produced when a needle or its hook passes through the inspection field of an optical sensor.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Time intervals between individual signal impulses are registered and if the interval between signal impulses is larger or smaller than that occuring between two previous signal impulses an alarm signal occurs. The alarm signal is activated when a needle is broken or bent. Memminger states that the invention results in a dependable, robust and reliable needle monitoring method.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: AT469256 Publication date: 15 June 2010 Applicant: Memminger IRO</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Yarn feeder</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Germany - Another patent application filed by Memminger concerns a new yarn feeder for circular knitting machines with an overload-protected anchoring clip (Fig 6). </span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJFA-Up2G_SxTW3KhSRoqEdmXrHChtsQ3VWjU8l2bhRmnJReZiqFwz8nLi-f2Gu5tzPkJK-ekTrtfdNj5lHQk1IkHndmhhCcVF_10C8C-JTAevC9A10xhmQsndjTh9dEHJNDJDJ9f_Q90/s1600/articleImage-1292.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJFA-Up2G_SxTW3KhSRoqEdmXrHChtsQ3VWjU8l2bhRmnJReZiqFwz8nLi-f2Gu5tzPkJK-ekTrtfdNj5lHQk1IkHndmhhCcVF_10C8C-JTAevC9A10xhmQsndjTh9dEHJNDJDJ9f_Q90/s1600/articleImage-1292.jpeg" height="294" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The aim is to improve handling security of the yarn-feed installation.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">According to the invention, the new yarn feeder has a clip (14) with overload protection in the form of a force limiting element (25) comprising a sheet-metal piece (24) with an attachment screw (18). The sheet-metal piece is dimensioned with respect to its flexural strength so it permits reliable tightening of the clip (14) preventing damage, in particular expansion.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Patent number: DE112007003544 Applicant: Memminger IRO Publication date: 15 July 2010</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-44796716252961462842014-06-09T00:10:00.001-07:002017-03-01T03:24:34.660-08:00TECHNOLOGY: Stoll creates a method for producing patterned knitted fabric<div dir="ltr" style="text-align: left;" trbidi="on"><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhi9Q4F8Ar0V4zdhvyKpmLdgjh1-GsnYlJICt6wRATffdOeYRXu9U7x5gDu68g77LnqVmQGo8EQCBs0aUUuQ27ta27rddR5Dl7bYNI1nRz0trLMECRyQr8Zq4oQ1OGyfOQLK6u44FDD2g0/s1600/Figure_1_-_Stoll_has_invented_a_new_method_for_producing_a_patterned_knitted_fabric.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhi9Q4F8Ar0V4zdhvyKpmLdgjh1-GsnYlJICt6wRATffdOeYRXu9U7x5gDu68g77LnqVmQGo8EQCBs0aUUuQ27ta27rddR5Dl7bYNI1nRz0trLMECRyQr8Zq4oQ1OGyfOQLK6u44FDD2g0/s1600/Figure_1_-_Stoll_has_invented_a_new_method_for_producing_a_patterned_knitted_fabric.jpg" height="320" width="249" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Stoll has applied for patent protection for a new method for producing a patterned knitted fabric (Fig 1). The production of a patterned knitted fabric with a course of stitches of base threads and patterned threads on a flat bed knitting machine with two opposing needle-beds involves (a) forming a course of base thread loops and inserting pattern thread loops on free needles of the other bed; (b) forming a base thread course using base thread needles; (c) wrapping caught loops of the other bed around pattern thread needles of one bed and slipping the wrapped loops with the stitches on the receiving needles; and (d) repeating steps (b) and (c).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Production of a patterned knitted article with courses of stitches consisting of a base thread (BT) and at least one pattern thread (PT) on a flat bed knitting machine with at least two opposing needle-beds involves a) at the start of the pattern repetition forming a course of stitches with the base thread and inserting catching loops with the pattern thread into free needles of the opposite needle-bed; b) forming a course of stitches with the base thread using the needles to be charged with the base thread to produce the pattern; wrapping the catching loops of the opposite needle-bed round the needles of the first bed to be charged with the pattern thread located on the receiving needle; repeating threads (b) and (c) until all catching loops for the pattern thread are wrapped and bonded into the article. An independent claim is included for a knitted article (specifically a flat or tubular article) formed by the process.</span></div><br /></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-74692895135739209522014-06-09T00:10:00.000-07:002017-03-01T03:24:34.708-08:00TECHNOLOGY: Groz-Beckert making installation or removal of circular knitting cylinders easier<div dir="ltr" style="text-align: left;" trbidi="on"><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgBM1MFzmQT3RY9zUt3fgxq0vi6w_Ik3O4bTZGHee4-HOh0DQRf5jsJWihzDTdaozHgLGmvNLqXcNKMj8N3WgiuIasxFbAj4btVQfg0qaupjJAZCmrVK_eGZNfXrjMtl9Utl2IGmZsWcm0/s1600/Figure_1_Groz-Beckert_has_invented_a_method_for_removing_circular_knitting_machine_cylinder_heads.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgBM1MFzmQT3RY9zUt3fgxq0vi6w_Ik3O4bTZGHee4-HOh0DQRf5jsJWihzDTdaozHgLGmvNLqXcNKMj8N3WgiuIasxFbAj4btVQfg0qaupjJAZCmrVK_eGZNfXrjMtl9Utl2IGmZsWcm0/s1600/Figure_1_Groz-Beckert_has_invented_a_method_for_removing_circular_knitting_machine_cylinder_heads.jpg" height="320" width="249" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Groz-Beckert has applied for a patent for a device, and the method for making it, which will make it easier to install or remove the cylinder of circular knitting machines (Fig 1). In order to make the work of changing the cylinder (12) of a circular machine easier, the upper part (28) of the support frame of the circular machine (10) is fitted with a lifting unit (47) for vertical raising of the cylinder (12) as well as facilities for the horizontal moving of the raised cylinder.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">To accomplish this, a movement rail is fitted (45) by means of a holding unit (48) to the upper support frame. The movement rail carries a movement truck (44) which supports a lifting unit (36). This lifting unit has an extension arm (43), a deflection pulley (39) and a winding unit (40).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The winding unit has a traction rope (38) which leads by way of a deflection pulley to a coupling unit (37) which acts as a gripper. The gripper grips the cylinder on the inside, so that it is lifted without the danger of damaging its delicate outside with its needle-tricks and other sensitive elements.</span></div><br /></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-264728961992830112014-06-09T00:07:00.000-07:002017-03-01T03:24:34.638-08:00Nano Hexagonal Boron Nitride Reinforced Polyvinylalcohol Nanofibres<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Abstract</strong></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Nanofibres are fibres having diameters in the nano scale, and they exhibit high properties due to their high surface area to volume ratios compared to fibres in the micro scale.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Boron nitride is a compound of boron and can have hexagonal (h-BN), cubic (c-BN), wurtzite (w-BN) and rhombohedral (r-BN) crystal structures. Hexagonal boron nitride has a similar structure to graphene. Hexagonal boron nitride has unique physical and chemical properties such as high temperature resistance and good resistance to oxidation.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In this study, nano sized hexagonal boron nitride (at wt %0.15, %0.30 and %0.45) added polyvinyl alcohol (PVA) based nanofibres and 100% PVA nanofibres are produced via electrospinning. The morphologies of the produced nanofibres are analysed by scanning electron microscopy (SEM), and the tensile strengths of the nanofibres are evaluated.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Key words:</span> </strong>electrospinning, nanofibres, hexagonal boron nitride, polyvinylalcohol</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Introduction</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Nanofibres are fibres having diameters in the nano scale, and they exhibit high properties due to their high surface area to volume ratios compared to fibres in the <span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">micro scale [Nijuguna, 2008].</span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Electrospinning is a widely used method for production of nanofibres where a high voltage is applied on a polymeric solution. Other methods for producing nanofibres are drawing, template synthesis, phase separation and self-assembly [Ramakrishna, 2005].</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Boron nitride is a compound of boron and can have four different crystal structures: hexagonal (h-BN), cubic (c-BN), wurtzite (w-BN) and rhombohedral (r-BN) [Mirkarimi, 1997]. Hexagonal boron nitride has unique physical and chemical properties such as high temperature resistance and good resistance to oxidation as well as being electrically insulative [Han, 2008; Sutter, 2011; Liu, 2013].</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In the literature there are few studies on nanofibres having hexagonal boron nitride reinforcement and those studies are mainly investigating the morphological and thermal properties of the nanofibres rather than their mechanical properties due to their fragile structures [Hwang, 2010; Uslu, 2012; Koysuren, 2012].</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Experiment</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Partially hydrolised PVA (polyvinylalcohol) polymer (Merck brand, having a MW of 70000) was dissolved in pure water at 16 wt% to produce nanofibres. Nano-sized hexagonal boron nitride (h-BN) at 70-80 nm particle size (Grafen Chemicals, Turkiye) was dissolved in absolute ethanol (Sigma Aldrich) to have 1 wt% h-BN solution.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The PVA and h-BN solutions were mixed at appropriate ratios to obtain hBN reinforced PVA nanofibres having 0.15 wt%, 0.30 wt% and 0.45 wt% of h-BN. Pure PVA nanofibres were produced using the PVA solution. The sample codes and percentages of the nanofibres are given in Table 1.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 1" class="left-image" height="143" src="http://www.wtin.com/media/15495/table-1_375x143.jpg" style="border: 0px; float: left !important; font-size: 11px; margin: 15px 15px 10px 0px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="375" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Nanofibres were produced in Istanbul ITA Tekstil Research Laboratories using a KatoTech brand electrospinning machine which works with a movable single syring</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">e and has a cylinder to collect nanofibre webs. The working parameters were 26,6 kV applied voltage, 0,003 ml/min solution feed rate, 10,05 m/min cylinder speed and 31,60 m/min syringe travelling speed. The distance between the syringe and the cylinder was 12 cm during the production.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The tensile strength of the produced nanofibres were evaluated. Nanofibres have very tiny and sensitive structures that might be easily broken when handling for mechanical testing, for this reason the tensile testing process requires care when handling the nanowebs. Nanofibre webs were cut at 4x6 cm rectangles and tested at 10 mm/min extension and 30 mm gauge length on a universal testing machine (Tinius Olsen, 10 kN) using a 100N load cell.</span></div><div class="right-image" style="border: 0px; float: right !important; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 11px; margin-bottom: 10px !important; margin-left: 15px !important; margin-top: 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;"><img alt="Table 2" height="159" src="http://www.wtin.com/media/15496/table-2_400x159.jpg" style="border: 0px; display: block; margin-bottom: 0px !important; margin-left: auto; margin-right: auto; margin-top: 0px !important; outline: 0px; padding: 0px; vertical-align: baseline;" width="400" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The morphological structures of the nanofibres were examined at Erciyes University with a Leo 440 scanning electron microscope at 20 kV. And the AFM (atomic force microscopy) analyses of the nanofibres were conducted at Nanomagnetics Instruments (Ankara, Turkey) using one of their AFM products named ezAFM on the dynamic mode using a PPP-NCLR cantilever. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="background-color: white; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Results and discussion </strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Tensile strength results of the nanofibres are given in Table 2. The tensile strength and elongation percent of the nanofibres showed increase with h-BN reinforcement. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Fig 2" class="right-image" height="154" src="http://www.wtin.com/media/15498/fig-2_356x154.jpg" style="border: 0px; float: right !important; font-size: 11px; margin: 15px 0px 10px 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="356" /><span style="background-color: white;"><img alt="Fig 1" height="162" src="http://www.wtin.com/media/15497/fig-1_356x162.jpg" style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;" width="356" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div class="left-image" style="border: 0px; float: left !important; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 11px; margin-bottom: 10px !important; margin-right: 15px !important; margin-top: 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Fig 3" height="150" src="http://www.wtin.com/media/15499/fig-3_344x150.jpg" style="border: 0px; margin: 0px !important; outline: 0px; padding: 0px; vertical-align: baseline;" width="344" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Fig 4" height="134" src="http://www.wtin.com/media/15500/fig-4_307x134.jpg" style="border: 0px; font-size: 11.111111640930176px; margin: 0px; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="307" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">The morphological structures of the nanofibres were examined at Erciyes University with a Leo 440 scanning electron microscope at 20 kV. The images of the samples are given in Figures 1-4. The nanofibres have diameters in the nano scale and they don’t have beads in their structures.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The AFM (atomic force microscopy) analysis of the pure PVA nanofibre sample is shown in Figure 5. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Fig 5" height="474" src="http://www.wtin.com/media/15501/fig-5.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="544" /></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-22955590398808821862014-06-09T00:05:00.000-07:002017-03-01T03:24:34.635-08:00Yarn stretch at sizing: A factor affecting warp breaks on loom<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Abstract<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The performance of a textile mill is mainly determined by the loom-shed efficiency, which entirely depends upon the quality of sized beam production. During the processing of material in sizing, the yarns are stretched, which is one important factor to be considered in producing a quality-sized beam. The stretch caused by tension leads to an increase in length and reduction in yarn as well as fibre cross-section. This phenomenon affects the strength of the fibre. The required quality-sized yarn for good weaving performance is high elongation at break. If this falls below a certain limit then the warp breaks will increase on the loom. For better elongation at break the yarn stretch at sizing should be at the minimum possible level and, particularly, the stretch at wet zone should be as low as possible. This study mainly focused on control of stretch percent, and elongation of sized yarn and unsized yarn as factors in reducing the warp breaks on loom. The study was conducted for different counts as well as for cotton and cotton-polyester blend yarn.<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Introduction<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The following figure shows the main stretching zones in the sizing machine where the yarn is under tension. In the sizing machine the yarn is to be kept under tension during processing in order to avoid the slackness of yarn during processing, which results in entanglement of the yarns with each other. The tension on the yarn during sizing should be only up to a certain minimum level in order to avoid excess stress on the yarn, which may results in warp breaks on the loom due to the loss of yarn elongation at break. Table 1 shows the minimum level of yarn stretch for three different counts.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Fig 1 Yarn" height="261" src="http://www.wtin.com/media/17387/fig-1-yarn.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="529" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Various zones of stretch control on modern sizing machines are:<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><ol start="1" style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Creel zone: Last warper beam to first squeezing roller</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Wet Zone: First squeezing roller to 2nd squeezing roller</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Drying Zone: First drying cylinder to last drying cylinder</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Splitting Zone: Last drying cylinder to drag roll</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Winding Zone : Drag roll to sizing beam</span></li></ol><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Stretch</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">When yarn is processed on a sizing machine the yarns are under tension. But this tension on the yarn during sizing is required, which results in a slight permanent stretch in the yarn. This permanent stretch causes decrease in elongation at break of sized yarn and this elongation in the yarn is called stretch. If the average extensibility of the sized yarn falls below a certain level, the less extensible portions in the yarn are likely to break during weaving.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Tensile Strength</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The tensile strength of the yarn must be increased by the increase in fibre-to-fibre friction due to cementing of size film, as well as by the addition of strength by size film itself.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Flexibility</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This property is particularly important in weaving. Sized warp yarn must be able to withstand repeated and extensive bending in the weaving operation without damaging the size film. Rupture of the film causes increased yarn friction in shedding and results in end break.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><img alt="Table 1,2,3" height="366" src="http://www.wtin.com/media/17388/table-1-2-3_693x366.jpg" style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;" width="693" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Elongation and Elasticity</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Elongation is the amount of yarn stretch before it breaks. Elasticity is the property of yarn, which allows it to return almost to its original length after the stretching tension is released. Stretch is a factor that directly contributes to elasticity and elongation. After tensioning the yarn, stretch occurs in the fibre, in the size film and in the yarn itself. It is found that the amount of elongation and elasticity present in the sized yarn are directly related to the physical properties of the fibre and the properties of sizing materials used.<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> <img alt="Fig 2,3" class="right-image" height="425" src="http://www.wtin.com/media/17389/fig-2-3.jpg" style="border: 0px; float: right !important; font-size: 11px; margin: 15px 0px 10px 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="370" /></span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Material and Method<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In this research study to test the effect of sizing stretch on end breakage rate at loom, yarns of three different count were selected, ie. 40s Ne, 45s Ne and 60s Ne. The selected yarns were stretched during the sizing process for five different stretching levels by adjusting creel tension as shown in Table 2. Then the five sized yarns of different stretching levels were tested for elongation at break and processed on loom to study the warp breakage rate.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Results and Discussion</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">In this research study five yarn samples of each count were taken, with five different yarn-stretch levels for each of the three different counts: viz. 40s Ne, 45s Ne and 60s Ne. Before the sized yarns were processed on loom their elongation at break was tested, by which it was possible to correlate this with warp breaks on loom. Table 3 shows the correlation of yarn elongation with the warp breaks at loom.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Table 3 and Figures 2-4 revels that, as the creel tension at sizing increases, the yarn elongation at break reduces due to higher stretching of yarn during sizing. By statistical analysis, ‘P’ value for elongation at break is 0.0002, which is less than 0.05, which confirms that there is a significant difference between the elongation percent for three different counts at five different yarn stretch levels.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It was also found that, if the yarn is given more tension during processing at sizing, its elongation at break reduces, which is reflected in an increase in warp breaks on loom. In a two-hour breakage study it was found that the increase in warp breaks was very pronounced for the highest stretch % for all counts, due to maximum loss in yarn elongation. For full beam breakage rate the study showed successive increase in warp breaks with increase in yarn stretch at sizing.<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Figure 4 confirms that, as the yarn stretch at sizing increases, the size pickup of the yarn reduces due to increase in yarn tension during sizing. This is due to the increase in fibre packing density, caused by yarn compactness resulting from the higher yarn tension during sizing.<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Conclusions<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">For 40s Ne yarn, if the yarn stretch at sizing is increased from 0.8% to 1.6% there is an increase in warp breakage rate on loom from 6.8 to 16.8 breaks/shift, due to reducing the yarn elongation by 20 to 25%. In the case of 45s Ne yarn, if the yarn stretch at sizing is increased from 0.6% to 0.8% there is an increase in warp breakage rate on loom from 5.1 to 17.3 breaks/shift, due to reducing the yarn elongation by 4.0 to 8.0%. The same trend is observed for the finer count.</span><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The main reason for sizing the yarn is to improve its weavability by penetrating the size paste into to the yarn body as well as making a cover of size paste on the yarn body, but it is found that as the yarn stretch is increased during sizing the size pick-up by the yarn successively reduces, which directly results in increase in warp breaks on the loom.<span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">By statistical analysis the ‘P’ value for warp breaks on loom due to reduction in size pick-up is 6.16E-09. It is less than 0.05, which confirms the dominant effect of size pick-up on warp breaks on loom.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">References</span></strong></div><ol style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">M.C.Paliwal and P.D. kimoti – Process Control in Weaving Published by Dr. N.E. Dweltz and shri R.C.Vohra for second Edition (Nov. 1974) Page no. 109 to 118.</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">M.C.Paliwal, P.D. Kimoti and Subramanian T.A. Process Control in Sizing Published by R.C. Vora for ATIRA. First Edition (April 1987) Page no. 16 to 24.</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Agrawal S.K. and Bai Subramanin Contribution of same variables to the Weavability of yarn, Part second Contribution of Stretch ATIRA Publication (Nov. 1986).</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Impact of stretch % and elongation% on loom performance, www.fiber2fasion.com</span></li><li style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Stretch% and elongation% in sizing: www. google.com.</span></li></ol></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-41706911849442728592014-06-09T00:03:00.001-07:002017-03-01T03:24:34.652-08:00How does loop length influence weft knitted fabric shrinkage?<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Knitters of cotton circular knitted fabrics are faced with increasing global competition and ever increasing demands for better quality and reliability. One of the key demands is for fabrics and garments with consistently low levels of potential shrinkage.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Excellent comfort properties of weft knits have seen them increasingly used in formal wear for men and women. But with technological advancement in fabric manufacturing and increasing customer awareness of quality, expectations have risen.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">However, knit goods are known to be prone to deformation during manufacturing and when worn. Knitting technology has advanced considerably during the past two decades with the introduction of various knitted structures, use of new and modified yarns and the versatility of modern knitting equipment.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dimensional stability of weft-knitted fabrics is a serious problem in view of fabric quality control. Generally the stitch density of plain knitted fabrics in the dry relaxed state is dependent only on the loop length and independent of other yarn and knitting variables. This study attempted to demonstrate the influence of loop length on the shrinkage properties of knitted fabrics.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Traditionally, cotton circular knitted products have been developed and optimised largely by trial and error methods but these methods will not be good enough for the future because they are too costly and uncertain. A modern quality assurance system requires firstly that product performance can be designed in advance by exact calculations and secondly that processing machinery can be regulated by reference to predetermined target levels of key product properties which can be measured continuously, on-line and used in feed-back loops to control some aspect of machinery settings. Figure 1 shows the stitch length (loop length) of a knitted fabric.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Figure 1 Loop Length Of A Knitted Fabric" height="272" src="http://www.wtin.com/media/14978/figure-1-loop-length-of-a-knitted-fabric.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="305" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For cotton circular knitted fabrics, there are three major requirements for achieving ‘low shrinkage by design’.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">• The fabric has to be correctly engineered for the required performance (appropriate choice of yarn and knitting conditions);</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">• Appropriate values have to be specified for the key fabric properties which will be used for process control (finishing targets);</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">• The finishing machinery has to be provided with appropriate sensors and regulators.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For a study of the dimensional properties, single jersey plain knitted fabric samples with four different loop lengths: 2.6mm, 2.65mm, 2.77mm and 2.95mm were produced. The fabrics were tested for GSM (g/sq m) and shrinkage lengthways and widthways in grey and after finishing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The knitted fabrics produced with four different loop lengths were tested for two fabric quality parameters: fabric GSM and shrinkage, shown in Table 1.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 1 Effect Of Stitch Length On Knitted Fabric Quality" height="317" src="http://www.wtin.com/media/14976/table-1-effect-of-stitch-length-on-knitted-fabric-quality.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="422" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Fabric GSM is found to be higher after the finishing treatment for all four different loop lengths due to absorption of dye in to the knitted fabric during processing.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Figure 2 shrinkage" height="271" src="http://www.wtin.com/media/14979/figure-2-fabric-weight-vs-loop-length.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="375" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The knitted fabric samples were tested for lengthways fabric shrinkage and results are shown in Table 2.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 2 Knitted Fabric Shrinkage With Respect To Stitch Length (1)" height="277" src="http://www.wtin.com/media/14980/table-2-knitted-fabric-shrinkage-with-respect-to-stitch-length.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="476" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">From statistical analysis of the data in Table 2, the ‘P’ value for fabric shrinkage in the lengthwise direction is 8.31E-09 and is less than 0.05, showing that there is a significant difference between the shrinkage values for different loop lengths. It is also found that the amount of shrinkage increases as the loop length of knitted fabric increases due to a reduction in the fabric’s stitch density.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Figure 3 shows that as the stitch length increases fabric shrinkage is also found to increase lengthwise. Fabric samples were also tested for widthwise shrinkage and the results are shown in Table 3.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Figure 3 shrinkage" height="267" src="http://www.wtin.com/media/14981/figure-3-fabric-shrinkage-lengthwise-vs-loop-length.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="409" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The statistical analysis of data in Table 3 shows that the ‘P’ value for fabric shrinkage in the widthwise direction is 0.528193 and is greater than 0.05, showing that there is no significant difference between the shrinkage values for different loop lengths.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 3 shrinkage" height="260" src="http://www.wtin.com/media/14982/table-3-knitted-fabric-shrinkage-wrt-stitch-length.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="401" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Figure 4 confirms that there is no such effect of variation in stitch length on the fabric shrinkage in the widthwise direction.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Figure 4 shrinkage" height="261" src="http://www.wtin.com/media/14983/figure-4-fabric-shrinkage-widthwise-vs-loop-length.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="417" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">As stitch length in the knitted fabric reduces, GSM increases with increasing stitch density and the fabric becomes more compact. When the knitted fabric is dyed and finished, fabric GSM is increased by absorption of the dye.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This study confirms that, after the finishing of knitted fabrics of different stitch lengths, there is more shrinkage of the fabric in the lengthwise direction than in the widthwise direction. Fabric shrinkage in the lengthwise direction is found to increase with increase in stitch length which reflects the diminishing fabric dimensional stability for higher stitch length knitted fabrics. There is no significant effect of variation in the stitch length on the knitted fabric shrinkage in the widthwise direction.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; font-size: xx-small; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Prof R N Narkhedkar is based at the Center for Textile Functions, NMIMS University, Shirpur, India</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">References</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Bayazit Marmarali A (2003) Dimensional and physical properties of cotton/spandex single jersey fabrics, Text. Res. J. 73 (1), 11-14.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Choi MS and Ashdown SP (2000) Effect of changes in knit structure and density on the mechanical and hand properties of weft-knitted fabrics for outwear, Text. Res. J. 70 (12), 1033–1045.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Doyle PJ and Hurd JCH (1953) Fundamental aspects of the design of knitted fabrics. J. Text. Inst. 44 (8), 561-578.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Keshkari KR (2002) Effect of yarn feed length on cotton weft knitted fabrics, The Indian Tex. J., 112(6), 131-136.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Knapton JJF (1979) The wet-relaxed dimensions of plain-knitted fabrics. J. Text. Inst. 70 (9), 410. Mikučionienė (2004) The dimensional change of used pure and compound cotton knitwear. Material Sci. 10 (1), 93–96.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-16881886787993428772014-06-09T00:03:00.000-07:002017-03-01T03:24:34.630-08:00Selection of Exhaustion Agents: A Dominant, Cost-Effective Solution for Cold and Hot Brand Reactive Dyes on Cotton Substrates<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Abstract</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Most dyes used for cellulose fibres today are reactive dyes, due to performance features such as higher fastness properties, brighter colour effects and a wider colour palette<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">1</span>. The range of available reactive dyes is wide, and enables a large number of dyeing techniques to be used<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">2</span>. This research was undertaken with a view to improving value addition to the substrate and reducing dyeing cost. In order to reduce the cost structure in the cotton-dyeing process, six dyes were selected and applied on cotton yarn, with 1% dye concentration, using selected exhaustion agents common salt, vacuum salt and Glauber’s salt, with 40gpl concentration and 16gpl concentration soda ash as a fixation agent. The process was followed by rinsing, washing and drying, and CIE Lab values of the samples were measured with a DataMaster V2.0 spectrophotometer, with a 10° normal observer and norm light D65. On yarn dyed with three shades, samples exhausted with Glauber’s salt exhibited high strength value and also showed a lower consumption of dyes as compared to the other two exhaustion agents.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Keywords: Exhaustion agent, fixation agent, washing fastness, effluent load, dye consumption</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Introduction</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Glauber’s salt is important in the manufacture of textiles. Glauber’s salt helps in ‘levelling’, reducing negative charges on fibres so that dyes can penetrate evenly in to substrate, so depth of colour with Glauber’s salt is more than with common salt and vacuum salt. Glauber’s salt is also environmentally friendly.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Methodology (Cold and Hot Brand Method)</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Three different reactive dyes, sourced from a commercial dye manufacturer, were selected from both cold brand ranges (RedM5B, Blue MR, Yellow M3R) and hot brand ranges (Red HE3B, Blue HERD, Yellow HE4R) and were used for reactive dyeing. Dyeing processes were carried out with dye concentrations of 1%. The dyeing procedure was followed by the addition of calculated amounts of salt solution (common salt/vacuum salt/Glauber’s salt) 40gpl and soda ash 16gpl after a regular interval. After dyeing the samples underwent washing and soaping.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">For cold brand reactive dyes, dyeing was carried out with a laboratory-scale dyeing machine with a liquor ratio of 1:10 at 30°C room temperature. The dyeing process was started with liquor containing alkaline, salt and dyestuff at 30°C, and the samples were then treated for 60 minutes, then rinsed at 60°C for 10 minutes, and 5 minutes in cold water. And samples were dried. The reflectance (%R) and CIE Lab values of the samples were measured with a Datacolor spectrophotometer with a 10° normal observer and norm light D65.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">For hot brand reactive dyes, the dyeing process was started with liquor containing alkaline, salt and dyestuff at 30°C, and after 15 minutes the temperature was raised to 80°C with a 2°C/min temperature rise ratio; the samples were then treated for 60 minutes. After dyeing, the samples were rinsed and neutralised (10 min at 80°C with 0.5 g/l acetic acid), and then rinsed at 80°C for 10 minutes, 95°C for 15 minutes (twice for 2% dyeing), 80°C for 10 minutes, and 5 minutes in cold water. The reflectance (%R) and CIE Lab values of the samples were measured with a DataMaster V2.0 spectrophotometer with a 10° normal observer and norm light D65.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Method of Testing</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Standard testing procedures were followed for the assessment of colour-fastness properties and colour-difference values were recorded by the ISO- 1 method.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Results and Discussion</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Effects of Dyeing Exhaustion Agents on Colour Depth (Strength %)</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Tables 1 represents the values calculated with reference to the samples of reactive-dyed fabrics, in which the sample dyed with common salt as the exhaustion agent was treated as standard sample and the samples treated with the exhaustion agents vacuum salt and Glauber’s salt were compared with the standard sample by DataMaster V 2.0 spectrophotometer. The values colour-strength % values obtained by spectrophotometer (Table 1) show that by changing the exhaustion agent (common salt, vacuum salt, Glauber’s salt), colour-strength % value increases significantly for the three shades of reactive-dyed yarn with 1% dye concentrations.<span style="border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> </span></span></div><table border="0" class="table-caption-center" style="border-collapse: collapse; border-spacing: 0px; border: 0px; clear: both; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; width: 3339px;"><tbody style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><tr style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><td style="border: 0px; margin: 0px; outline: 0px; padding: 0px; text-align: center !important; vertical-align: top;"><span style="background-color: white;"><img alt="Table 1 Washing Fastness Properties Of Cotton Yarn , With Cold And Hot Brand Reactive Colours ; By ISO-1 Method" height="318" src="http://www.wtin.com/media/16050/table-1-washing-fastness-properties-of-cotton-yarn-with-cold-and-hot-brand-reactive-colours-by-iso-1-method_739x318.jpg" style="border: 0px; float: inherit !important; margin: 0px 0px 3px !important; outline: 0px; padding: 0px; vertical-align: top;" width="739" /></span></td></tr><tr style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><td style="border: 0px; margin: 0px; outline: 0px; padding: 0px; text-align: center !important; vertical-align: top;"><span style="background-color: white;">Table 1: Washing fastness properties of cotton yarn, with cold and hot brand reactive colours; by ISO-1 method</span></td></tr></tbody></table><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In reference to Figures 1 and 2, it was observed that In all three cold-brand colours (1 = Red M5B, 2 = Blue MR, 3 = Yellow M3R) and hot brand colours (Red He3B, Blue HERD, Yellow HE4R) the same trend was observed. Common salt exhaustion produced low colour depth while vacuum salt gave comparable shade strength and Glauber’s salt recorded the highest strength. The above study reveals that, as the exhaustion agent changes from common salt to vacuum salt and Glauber’s salt, shade strength significantly increases, which leads to a reduce cost structure and consumption of dye and improves the efficiency of cotton-dyeing plant. If suitable exhaustion agents are not selected during the dyeing process, depth of colour reduces and the substrate requires additional processing, which consumes extra time leads to a reduction in the efficiency of dyeing plant. </span></div><table border="0" class="table-caption-center" style="border-collapse: collapse; border-spacing: 0px; border: 0px; clear: both; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; width: 3339px;"><tbody style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><tr style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><td style="border: 0px; margin: 0px; outline: 0px; padding: 0px; text-align: center !important; vertical-align: top;"><span style="background-color: white;"><img alt="Fig 1" height="272" src="http://www.wtin.com/media/16051/fig-1.jpg" style="border: 0px; float: inherit !important; margin: 0px 0px 3px !important; outline: 0px; padding: 0px; vertical-align: top;" width="620" /></span></td></tr><tr style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><td style="border: 0px; margin: 0px; outline: 0px; padding: 0px; text-align: center !important; vertical-align: top;"><span style="background-color: white;">Figure 1: Effect of different exhaustion values on colour strength for cold brand (1= Red M5B, 2 = Blue MR, 3 = Yellow M3R)</span></td></tr></tbody></table><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><table border="0" class="table-caption-center" style="border-collapse: collapse; border-spacing: 0px; border: 0px; clear: both; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; width: 3339px;"><tbody style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><tr style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><td style="border: 0px; margin: 0px; outline: 0px; padding: 0px; text-align: center !important; vertical-align: top;"><span style="background-color: white;"><img alt="Fig 2" height="250" src="http://www.wtin.com/media/16052/fig-2.jpg" style="border: 0px; float: inherit !important; margin: 0px 0px 3px !important; outline: 0px; padding: 0px; vertical-align: top;" width="625" /></span></td></tr><tr style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><td style="border: 0px; margin: 0px; outline: 0px; padding: 0px; text-align: center !important; vertical-align: top;"><span style="background-color: white;">Figure 2: Effect of different exhaustion values on colour strength for hot brand </span></td></tr></tbody></table><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; line-height: 17px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Practices Suggested for Obtaining Correct Shade in Dyeing</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">1. Before consumption of any dye, the colour strength received from the supplier should be compared with running colour because, in the dye manufacturing, batch-to-batch variations are introduced. In order to minimise these effects, the strength should be evaluated and compared with supplied dye. If the strength of the supplied dye is higher, the consumption of the dye must be reduced.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">2. Selection of exhaustion agents is very important in obtaining shade strength. From Figures 1 and 2 it was observed that the shade produced with Glauber’s salt recorded highest strength with both cold and hot brand colours. Almost same trend was observed with both cold and hot brands in the three basic colours (ie. red, blue and yellow) and there is dominant effect of Glauber’s salt exhaustion on shade strength.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">3. Effect of MLR on shed depth: lowering the liquor ratio leads to improve in shade strength. In reactive dyeing, lowering the liquor ratio brings down the volume of water used and the waste generated. Apart from the easier handling of lower volume of effluent, the dosing of chemicals and auxiliaries in the dye bath is done on the basis of g/litre of liquor. This significantly reduces the quantities of chemicals and auxiliaries and finally the effluent load.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">4. Right-first-time approach : Carefully following the dyestuff manufacturer's recommendations for salt, alkali usage, temperature, time, etc, ensures the optimum fixation levels and right-first-time production, thereby avoiding the need to make shading additions. Computer colour matching is helpful in this regard.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Conclusions</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This research study revealed the effects of exhaustion agents on colour strength %. Using Glauber’s salt in dyeing instead of common salt and vacuum salt significantly reduced dyeing cost, which is cost-effective and important for both small and large-scale industries.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In effluent treatment, only a small quantity of salt is removed. Thus a major quantity of salt enters the environment on discharge of wastewater. High salt concentration in the effluent has a number of disadvantages, such as toxicity to organisms, and also causes land infertility. Using of Glauber’s salt with reactive dyeing leads to reduced effluent load, produces brighter shades also reduces consumption of dye.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">From the study it was confirmed that the variety of shades produced on yarn exhibited adequate all-round washing fastness and high colour strength was reported with Glauber’s salt. Dyeing in the presence of Glauber’s salt improves the properties of the cotton substrate. Use of Glauber’s salt in reactive dyeing reduces the effluent load and, saves the consumption of dyes and produces bright shade, with an improvement in cost structures. Using a short liquor ratio reduces the use of electrolyte and the amount of energy required to heat the dye bath as well as the water consumption.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">References</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">1. Arts of Dyeing, B.S. Chauhan, Second Edition 2003 Page No.86 - 115<br />2. Principle and practice of dyeing, Prof. V. A. Shenai, Chapter No. II, III, IV, pp13-77; Sevak Publications, 21 November 1991.<br />3. Dyeing effect of bi-functional reactive dye on knitted cotton fabrics, M.M. Dalal, K.R. Desai, South Gujarat University. American Dyestuff Reporter April 1996.<br />4. Novel dyeing technique for enhancing colour strength dyestuff reported and fastness properties of cotton fabrics with natural dyes, R.R. Mahangade, P.V. Varadrajan, J.K. Verma, H. Bosco, IJFTR volume no.34 ,Sept 2009, pp279-282.<br />5. Canonizing efficiency and performance of antimicrobial agent on cotton fabric dyed with vinyl sulphone based Reactive dye, Shaukatali , Sameera Saleem, Saima Umbreen, IJFTR volume no. 34, Sept 2009, pp274-278.<br />6. Effects of Warp-Weft Density Variation and Fabric Porosity of the Cotton Fabrics on their Colour in Reactive Dyeing, Ahmet Cay, Rıza Atav, Kerim Duran, Ege University, Department of Textile Engineering, Izmir, Turkey, FIBRES & TEXTILES in Eastern Europe January/March 2007, Vol. 15, No. 1 (60).<br />7. Colour for textiles, A user’s handbook, Wilfred Ingamells PhD MSc CText FTI C Col FSDC. School of Home Economics and Institutional Management, University of Wales, Cardiff, UK<br />8. Shore J., Cellulosic Dyeing (Society of Dyers and Colourists, London), 1995</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-53608749553234667102014-06-08T23:53:00.000-07:002017-03-01T03:24:34.671-08:00RESEARCH: Developing digital printing on 100% Merino<div dir="ltr" style="text-align: left;" trbidi="on"><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgUp8Dh1Hu3BkuCXaoPne-A04tia6z4Uf13Wf1VPvMXgnGHE47TRG24444w82tuDN6P73NoK7lTyIlFj3tP1ehLv_eLsZ3Xntw-DWf5EMCGN5RCY-NUZW5UckPgyYqxcz4aISkKJ6PDnzE/s1600/Digitally_printed_Merino_knitwear._Credit_-_Alysha_Gover.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgUp8Dh1Hu3BkuCXaoPne-A04tia6z4Uf13Wf1VPvMXgnGHE47TRG24444w82tuDN6P73NoK7lTyIlFj3tP1ehLv_eLsZ3Xntw-DWf5EMCGN5RCY-NUZW5UckPgyYqxcz4aISkKJ6PDnzE/s1600/Digitally_printed_Merino_knitwear._Credit_-_Alysha_Gover.jpg" height="269" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The Textile + Design Lab at Auckland University of Technology (AUT), New Zealand, is engaged in design and innovation using fashion and textile technology for the purposes of research, product development, training and education. The lab covers knit design, e-textiles, digital supply and distribution chains, sustainability and resource development.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Digital textile design and development has been a key area of focus for the past six years. The Textile + Design Lab has made significant efforts to overcome some of the technical issues encountered when trying to digitally print Merino wool fabrics.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Whilst the lab had been successfully digitally printing Merino/possum knitwear for several years, they were not able to achieve the same quality of prints on 100% Merino.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“The prints had a mottled appearance and dye retention and cross staining of residual dye were also concerns on both woollen fabrics and knitwear,” explains Peter Heslop, manager of the Textile + Design Lab.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“Our Shima Seiki flatbed printer was developed with printed knitwear in mind so preparing the knitted products prior to printing and developing a suitable wet finishing process were the main obstacles that we had to deal with.”</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Heslop and his team applied for funding from the commercialisation department to conduct the R&D work. Typically projects involve individuals or groups of six or more research staff and postgraduate students, depending on the nature of the work. Many of the problems they encountered were related to raw material preparation and post printing processes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“The funding enabled us to engage the help of a textile chemist who helped us formulate processes, particularly in the wet finishing area,” says Heslop. “The results of the work we have done have helped us to identify certain raw materials that have better dye affinity, which in turn give us good vibrant colours without any residual dye transferring onto the printed fabric or garment.”</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">With digital printing there is no limit to the number of colours that can be incorporated into a single design. The Textile + Design Lab encourages its students and commercial partners to use this advantage to create a point of difference between their designs and those printed conventionally.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">One such commercial partner is New Zealand Merino performance wear company Icebreaker, which has worked with the lab since it was opened in 2006. Icebreaker approached the researchers to work on the development of prints for 100% knitted Merino base layer garments.</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjK5QZ1lyEVsltfv_gvQ1t68495vJXDrWZWgt7dQqi7vnNWQFmpj1M_shTDDrje4nTp0TQkjtjducHHzhqvb1aePUBZnrNip7A5-q1r2CRVIUAOyqg243fQCp_r3FkCpgsTYeS4oT0Bibc/s1600/Digitally_printed_Merino_single_jersey_knit._Photography_by_Textile___Design_Lab.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjK5QZ1lyEVsltfv_gvQ1t68495vJXDrWZWgt7dQqi7vnNWQFmpj1M_shTDDrje4nTp0TQkjtjducHHzhqvb1aePUBZnrNip7A5-q1r2CRVIUAOyqg243fQCp_r3FkCpgsTYeS4oT0Bibc/s1600/Digitally_printed_Merino_single_jersey_knit._Photography_by_Textile___Design_Lab.jpg" height="297" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“Although we were fairly ‘green’ with regard to digitally printing on wool fabrics at that time, we took up the challenge by colour matching to their palette and turning around about eight new designs in a matter of a week or so,” says Heslop.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“This product development exercise highlighted just how quickly new products could be converted from design to finished garment, another advantage of the digital printing process.”</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The Textile + Design Lab is not solely focused on digital printing, carrying out significant R&D work on whole garment and intarsia knitting technology. The lab originally installed a Shima SES 7 gauge wholegarment machine and a 10 gauge wholegarment accessory machine. The ultimate aim of the research is to support domestic knitwear production.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“One of our objectives is to increase capability within the New Zealand apparel and textile sectors by engaging with the industry so designers and manufacturers can access this state of the art technology, develop new products and then make informed decisions as to whether this technology is right for them,” Heslop explains.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“There have been seven or eight cases whereby our commercial partners have invested in their own wholegarment machines having gone down this path with us. That in turn has helped to retain more knitwear production in New Zealand, which in turn should create job opportunities for our graduates.”</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Some of the more hi-tech R&D has incorporated conductive materials, such as the lab’s work with Zephyr Technology, a New Zealand based specialist in physiological monitoring devices.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Heslop’s team has also collaborated with Footfalls and Heartbeats, a developer of smart knitted structures intended for the first response, sports and medical sectors. These smart garments measure the wearer’s respiratory rate without the use of obtrusive monitoring devices. Research with Footfalls and Heartbeats is likely to continue to the end of 2013.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“The acquisition of a 14 gauge Shima intarsia machine about 12 months ago has helped us to develop more sophisticated patterning for this type of application, as well as being able to produce more complex designs for knitwear,” Heslop adds.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">“We are optimistic about getting involved in R&D projects in the medical/healthcare sector. We also expect to see more design led research activity from our postgraduate students particularly in the areas of fashion, knitwear and textiles.”</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Over the past six years, the Textile + Design Lab at AUT has built up technical expertise in both electronic flatbed knitting and digital textile printing. Heslop and his team are encouraged by the number of enquiries they receive from overseas, suggesting that the international profile of the R&D centre is growing. The ultimate aim of the lab is to continue to expand, whilst at the same time supporting its New Zealand based students and commercial research partners.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-68088086367824202092014-06-08T23:52:00.000-07:002017-03-01T03:24:34.687-08:00Digitally printing wool, why not?<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Many digital printers and academics, when broached about the subject of digitally printed wool fabrics and garments, had already placed this topic in the ‘too-hard basket’ and had moved on to other things.</span><img alt="wool thumbnail" class="right-image" height="150" src="http://www.wtin.com/media/14954/wool-thumbnail.jpg" style="border: 0px; float: right !important; font-size: 11px; margin: 15px 0px 10px 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="120" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Being based in a country that claims to produce the world’s best wool fibre prompted New Zealand’s Auckland University of Technology’s Textile and Design Lab (TDL) to pursue the idea of digitally printed wool with more vigour than most, in an effort to prove or disprove its viability.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The TDL supports both AUT and external students, as well as working with commercial partners on product development, prototyping, sampling and small-scale production projects. The lab has been digitally printing knitwear and fabrics for nearly 7 years and, while much of the demand for its printed fabrics has been for silk and cellulosic materials, it has seen an increase in demand for digitally printed merino wool and merino blended knitwear, as well as single jersey merino fabrics.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The lab’s first sortie into digitally printed merino fabric was in 2007, when it was approached by Icebreaker to help their design team develop some prototype prints for a new range of base-layer garments. The attraction of using digital printing for this project meant the client could circumvent the long-winded development process associated with screenprinting and take advantage of the quick turnaround time afforded by the lab’s digital printer. Strike-offs to the client’s colour palette were able to be shipped within a matter of days.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">However, staff at the lab were concerned about three specific issues that continued to manifest themselves when digitally printing wool fabrics and garments: firstly, the degree of variation in dye up-take between the raw materials it was printing; secondly, the tendency for solid colours to appear mottled; and finally, the degree of cross-staining that occurred no matter how thorough the wash-off process.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">When digitally printing clients’ knitwear, the lab has little control over where the yarn is sourced, so routine test printing of each lot has become standard practice. Fabrics, on the other hand, are sourced directly by the lab and, after extensive trials, it has settled on locally produced chlorinated shrink-resist and whitened knitted merino wool fabrics from Levana Textiles and Designer Textiles, and natural woven merino fabrics that were developed in New Zealand and now manufactured globally.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The bleaching process applied to the knit fabrics increases the affinity for the reactive dye applied by the lab’s Shima Seiki flatbed printer, thereby reducing the amount of residual dye in the wash bath. According to a consultant dyeing-and-finishing expert who has worked with the lab, the wash fastness of reactive dyes on shrink-resist merino fabrics is superior to that of acid dyes. The whitening process is also more conducive to achieving more vibrant colours.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The woven wool fabrics that have been adopted are light-weight worsted spun merino fabrics that have been mechanically finished to allow machine washability. In spite of the natural colour of these substrates, strong vibrant colours can still be attained.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In 2010 the lab acquired some internal R&D funding that enabled it to contract an experienced wool-textile chemist to advise and help formulate new wet-finishing recipes to overcome the problem of cross-staining. At the same time, it acquired a larger commercial-sized washing machine that facilitated increased water to fabric ratio, a major contributory factor in overcoming colour transfer problems.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Achieving the right wash-bath conditions for wet finishing wool fabrics and garments was accomplished by trial and error until the optimum pH level was attained. The lab introduced a 2-stage gentle-action wash cycle, which involved increasing the pH level in the first wash cycle, and this significantly reduced the propensity for loose dye to adhere to the fabric. A liquid soaping agent was introduced into the second wash cycle before rinsing and hydro extraction.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Tumble drying the fabric was deemed partially responsible for disturbing the surface fibres, thereby contributing to the mottling effect, and was eliminated from the lab’s finishing process in favour of open-width tunnel drying.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-72673778184296706462014-06-08T23:48:00.000-07:002017-03-01T03:24:34.706-08:00FOCUS: Circular knitting technology to eliminate fabric faults<div dir="ltr" style="text-align: left;" trbidi="on"><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg94UmKX3qmeBhpUl4vQdWPLEa_1QWSJstlAW-KVV56HSr78vZG_pIf6syyW3W51Qe-MkM4XkIbKWb2jd5Zs5MS6Xfdet7TYL6IzTOa7WgffZluFAPiIv8zfOr4Kkw0JgIv-XDvOeXG24s/s1600/KI_cir_knit_2.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg94UmKX3qmeBhpUl4vQdWPLEa_1QWSJstlAW-KVV56HSr78vZG_pIf6syyW3W51Qe-MkM4XkIbKWb2jd5Zs5MS6Xfdet7TYL6IzTOa7WgffZluFAPiIv8zfOr4Kkw0JgIv-XDvOeXG24s/s1600/KI_cir_knit_2.jpg" height="223" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The ultra fine gauge single jersey machine trend is led by European machine builders with most of the Asian manufacturers following in their wake. Machine models produced with and without sinkers with gauges up to 60/62 needles per inch are now the norm.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Machine builders have undergone a major rethink regarding knitting head design, knitting actions, knitting elements and tighter engineering tolerances. Finer gauges highlight fabric defects all the more, which are either caused by knitting elements, mechanical tolerances or loop formation methods.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">All prominent machine builders experienced these challenges in the past. The elimination of fabric defects has prompted some machine manufacturers to redesign knitting heads, both with sinkers and without in order to overcome them. These new developments have also led to improved machine speeds without compromising fabric quality and performance. The advent of ultra fine gauge machines has also forced yarn spinners to improve the quality of their fine yarn counts and minimise the variances which hitherto would not be seen in coarser gauge fabrics.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The Santoni flagship in its ultra fine large diameter range is the Atlas single jersey model. The Atlas HS model has been designed without loop forming sinker elements. This machine has, however, retained the fabric web holding capacity in the form of holding down jacks; this idea has been patented by Santoni.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The holding down jacks come into play as the cylinder needles are cammed upwards and thus holding down the fabric. As the cylinder needles descend, the jacks are rendered out of action and are not involved in the stitch formation process as the needles reach knock-over point at the top of the precision ground cylinder.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Removing sinkers from the loop formation process eliminates any loop distortions caused by sinker manufacture variance and also movement of the sinkers themselves. Stitch formation is also less prone to yarn breakages that can occur during the “robbing back” syndrome from adjacent knitted loops.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The result is that the knitted loops are compact and smaller than those made on conventional sinker machines. Another advantage of the Atlas model is the avoidance of sinker marks on the fabric which tend to increase as the machine gauge becomes finer on conventional models.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">On traditional sinker machines, loops tend to be longer as the yarn is dragged over the sinkers, but because the Atlas knitting action has no sinkers, the shorter stitch length gives compact loops and therefore better fabric density, appearance and handle. It also goes some way to eliminating spirality by reducing the loop twist factor due to compactness of the stitches. The greater fabric density also allows finer yarns to be used when certain fabric weights are required, instead of using coarser bulkier yarns which compromise fabric properties.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Higher fabric density also reduces the residual shrinkage factor present in all weft knitted fabrics. Using the holding down jack system also permits the machine to operate with a reduced fabric takedown, rendering a better and more uniform fabric quality. The holding down jack system allows an easy knitting restart after a fabric press-off.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The Atlas HS has improved cam profiles, taking into consideration angle of impact of the needle butts and needle acceleration at the point of stitch knock over. These studies have led to fewer needles being active in the stitch formation process with a subsequent reduction in stresses as the yarn is fed to needles.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The cam profile also allows the machine to keep the full complement of knit feeds. The improved camming, absence of the sinker ring and related friction together with an in-built air cooling system on the cylinder, enables the machine to perform at a higher operating speed, e.g. a 30in diameter machine can run at 45rpm (conventional gauges).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The Atlas HS model is available in 30in, 32in and 34in diameter and in gauges from 40 n.p.i. up to 62 n.p.i. All models have approximately 2.9 feeds per diametrical inch. The machine is equipped with two cam tracks and can be supplied in open width format or with a traditional tubular frame.</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjQh60oVmqZFtIQvu65QFdzkz_0K56Js6j1jFVY4jkL94HA5uefvVZKLv0T60oXoHTI64RGLF6xxapmLgdprROCxAsw1b-hYXmPmrQ9AW147NiHsEreqoylP6V676LhWvnG8kXQ5jZ3Vxk/s1600/KI_cir_knit_1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjQh60oVmqZFtIQvu65QFdzkz_0K56Js6j1jFVY4jkL94HA5uefvVZKLv0T60oXoHTI64RGLF6xxapmLgdprROCxAsw1b-hYXmPmrQ9AW147NiHsEreqoylP6V676LhWvnG8kXQ5jZ3Vxk/s1600/KI_cir_knit_1.jpg" height="250" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Cam boxes are made from Ergal, an extremely light aluminium alloy that has very good heat dissipation properties which avoids dimensional changes during production cycles. Yarn carriers are made from black Zirconium allowing greater visibility when using elastomeric yarns.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Mayer & Cie has several ultra fine gauge machine models in single jersey which are versatile and give a high performance. The MV 4-3.2 II is Mayer & Cie’s top of the range model for ultra fine gauge fabrics. This machine has a newly designed knitting head.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The new knitting head developments also reduce fluffing, increasing quality and performance. The machine also has individual adjustable sinker cam boxes; double sinker guidance with revised sinker design, which halves the wear and tear factor and ensures a uniform fabric appearance; fewer faults; lower costs and a higher productivity.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This is the result of three years of studies and trials aimed at overcoming horizontal and vertical fabric defects associated with ultra fine gauge machines. Mayer & Cie has more than 5,000 machines in the field in daily use already, which proves the track record of this particular model. The machine is equipped with one, two three or four needle tracks depending on customer requirements. The camming incorporates three needle positions with four types of needle, and various kits can be supplied for different fabric production capabilities.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The stitch cams are diagonally set, giving a clean loop knock-over even for lightweight knits. The diagonal cam system also eliminates the need to reset the yarn feeders. The machine also has a collective central stitch mechanism for making rapid quality adjustments. Machine diameters vary from 26in up to 48in and machines are available in gauges from 12 n.p.i. up to 60 n.p.i. The machine is supplied with short needles for single jersey production and holding down sinkers.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The cam box sections are made from Perunal, a high tech material used in the aerospace industry. This material has outstanding dimensional stability at different temperatures, reducing wear and heat dissipation. Perunal does not oxidise and is substantially harder than conventional materials used for cam box manufacture. Other features of the MV4 – 3.2 II fine gauge machines include a temperature controller, which keeps the machine operating temperature within the range of 33C to 40C.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The temperature controller can also be used to heat up machines after a weekend shutdown using a timer. The machines are then ready to run on the first production shift at the correct temperature.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Other features of the machine include the Coni++ positive feeding system equipped with ceramic pins in the capstan cages to avoid wear and tear. Mayer & Cie also has its own cylinder production within the same group. The machine is available in open width frame format with facilities for producing fabric rolls of up to 600mm and can be supplied with a fabric folding device for use with tubular frames.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In response to market demand and by working closely with several of Europe’s leading fabric producers, Monarch launched its first range of high definition (HD) fine gauge single and double jersey models in 2010.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Because of the positive reaction to this range, Monarch has now developed and introduced additional models, each incorporating the latest technology to ensure maximum productivity and cost efficiency. By pushing forward the barriers of technology, Monarch has provided its customers with the opportunity to create high performance, super lightweight fabrics with and without power stretch and with unique comfort and handle aesthetics, together with a design potential not previously possible.</span></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgg7168QLOLO57xNCcqR8lp8ouhNi20fGoH213HNgQC1rU-pnsEDqtBLzWKt0lDy0tle4XyIoSWZ9YnNeJOjdGXTm5CEniXsG4oDVyJG6CEeb_ftC0TVEuKZvzpiJXciKmVDpxHlZyTOOE/s1600/KI_cir_knit_3.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgg7168QLOLO57xNCcqR8lp8ouhNi20fGoH213HNgQC1rU-pnsEDqtBLzWKt0lDy0tle4XyIoSWZ9YnNeJOjdGXTm5CEniXsG4oDVyJG6CEeb_ftC0TVEuKZvzpiJXciKmVDpxHlZyTOOE/s1600/KI_cir_knit_3.jpg" height="244" width="320" /></a></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><br /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Customers can now choose from a wide variety of models including the OD4-VSEC7CS single jersey electronic jacquard machine produced in 34in diameter, 44 gauge with 84 feeds and a speed factor of up to 550. Also available is model OD4- VXC3.2, a 30in diameter, 60 gauge, 96 feed machine for the production of super fine basic single jersey structures, with a speed factor of up to 900.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">There are some signs indicating a growing demand for fine gauge striped fabrics. The multi-feed single jersey electronic jacquard model SEC-4BFY6 is fitted with F-type 6-colour stripers at each feeder to maximise productivity. Available in 26, 30 and 34in with 30, 42 and 48 feeds respectively, and in gauges up to 36 n.p.i., this model offers 3-needle selection based on SS actuators, whilst the cylinder cams are semi-closed for positive 3- position knit, tuck and welt control.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Designers have the opportunity to create new ranges of fine gauge 6- colour stripers with single jersey electronic jacquard designs or as 6- colour stripes incorporating 3-position structure patterns.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Initially, designers were, by the careful selection of yarns such as polyamide and cotton, in combination with elastomeric yarns, specifically engineering fabric weights, appearance, handle, drape, stretch and power performance, targeting lingerie, intimate apparel, sportswear and men’s underwear. However, Monarch’s design team has been working very closely with customers to develop the second generation of HD fine gauge fabrics for such diverse end-uses as automotive and household textiles as well as apparel.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The Terrot ultra fine gauge single jersey range comprises the S296-1 and S296-2. These two models have been re-engineered giving refined needle and sinker movements during the stitch forming process. They are produced in diameters from 26in to 44in and in gauges up to 54 n.p.i. and have fourcylinder needle tracks. The machines can be supplied in open width format for fabric rolls of up to 800mm with doffing device and 1050mm without doffing device.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The ultra fine contribution from Orizio comes in the form of the JPF and JPA models. These models are produced in 30in diameter and in gauges from 40 up to 52 n.p.i. The JPF has 1.6 feeds per diametrical inch and the JPA has two feeds.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The ultra fine gauge BSM 3.0 model from the Beck group is produced in diameters from 14in up to 42in and in gauges up to 62 n.p.i. The machine has 2.5 feeds per diametrical inch and operates at a peripheral speed of 1.4m/sec. The machine comes with all standard accessories and can be supplied in open width format.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-52244101465911751782014-06-08T23:45:00.001-07:002017-03-01T03:24:34.667-08:00Influence of Different Metal Electrodes on Electrocoagulation Process for Treatment of Disperse and Reactive Dye Wastewater<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Abstract</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Electrocoagulation is an electrochemical dissolution technique in which coagulating agents are generated in situ and used for treating wastewater. It could also be an effective tool for treatment of colour from textile and dye wastewaters with high removal efficiency and it rapidly removes the chromophores and by-products of dye solutions. Different metal electrode configurations were operated under galvanostatic mode to treat dye wastewater. Electrocoagulation processes were found to give excellent dye removal efficiency. Aluminium electrodes gave better removal efficiency in C.I. Disperse Blue 79 containing wastewater, whereas iron electrodes gave better removal efficiency in reactive dye Drimarene Navy HF-GN containing wastewater. A combination electrodes (ie. one iron and one aluminium electrode as anodes and one iron and one aluminium electrode as cathodes) gave high colour removal efficiency for both wastewaters containing reactive and disperse dye, and hence are found to have potential to be used in commercial electrocoagulation processes dealing with different kinds of dye effluent.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Keywords:</span></strong> Electrocoagulation, Dyes, Iron electrodes, Aluminium electrodes, DC current, Wastewater</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Introduction</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Colour plays an important role in the fashion and textile business. Our ever-growing fashion industry is conceiving new colours and designs, thereby presenting stern challenges not only for our dyers worldwide to achieve them but also for our society in terms of health, safety and environmental concerns.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In textile processing, the percentage of dye that remains unfixed to the fibre during the dyeing process and finds its way into the effluent ranges from 5-50%<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">1</span>. This dyeing effluent affects the aesthetics of water and also poses serious threat to aquatic life due to its interference with photosynthesis by reducing the transparency of water and also by the presence of hazardous and toxic compounds, especially azo dyes, salts, etc, which must be removed before discharging.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Several conventional methods, such as chemical coagulation and flocculation, biological treatment and tertiary treatments like adsorption, oxidation and filtration are used for colour removal but each suffers from its own limitations<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">2</span>. Chemical coagulation leads to a large amount of sludge formation<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">3</span>, whereas micro-organisms used in biological treatments are vulnerable to some commercial dyes. Tertiary treatments are often expensive and have operational problems such as regeneration and fouling of adsorbents<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">4</span>, clogging of membrane pores<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">5</span> and generation of sludge<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">6</span>. Ozone treatment gives satisfactory results towards removal of direct, acid and cationic dyes but is not very effective towards disperse and vat dyes<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">7</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Our pursuit for sustainability is leading us to various developments in wastewater treatment technology. Electrocoagulation [EC] is an emerging technology and is a combination of three foundation technologies of electrochemistry, coagulation, and flotation<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">8</span>. Electrocoagulation is different from the conventional chemical coagulation process as, in the EC process, coagulating agents are generated in situ; and it offers wide advantages, such as no chemical use, less and stable sludge formation, less salinity of treated water and effectiveness in a wider pH range (4-9). Also, EC can be applied in both batch and continuous processes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Electrocoagulation is an electrochemical dissolution technique for treating wastewater, in which sacrificial metal electrodes (Al or Fe) release cations and form various metal species (monomeric and polymeric) into solution when a current is applied across these electrodes. These metal species can interact with the pollutant in different ways; for example, the metallic ionic monomeric species can neutralise the charge of the pollutants by adsorption on their surfaces (or by binding to their ionised groups) thus reducing the electrostatic interparticle repulsion to the extent that the Van der Waals attraction predominates; the metallic ionic polymeric species can bind to several particles (or molecules) of pollutant at a time; and/or the pollutants can be enmeshed into growing metallic hydroxide precipitates, or can be adsorbed on to their surfaces<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">9</span>. EC also liberates hydrogen gas at the cathode, which attracts the flocculated particles and floats the flocculated pollutants to the surface through natural buoyancy. Thus electrocoagulation can remove a wide range of dissolved and colloidal contaminants from wastewater.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In electrocoagulation, metals producing trivalent ions such as aluminium and iron are preferred as anodes, as trivalent ions have a higher ability to adsorb on to particles in the water than bivalent ions because they have a higher charge density. The metal ions generated hydrolyse in the electrocoagulator to produce metal hydroxide ions and neutral M(OH)<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">3</span>. The low solubility of the neutral M(OH)<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">3</span>, mainly at pH values in the range of 6.0–7.0, promotes the generation of sweep flocs inside the treated waste and the removal of the pollutants by their enmeshment into these flocs<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">10</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Fe Electrode Reaction</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In the EC process involving iron electrodes, two mechanisms have been proposed to describe the formation of H<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">2(g)</span> and OH<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">-</span> at the cathode and Fe<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">2+</span>/Fe<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">3+</span> ions and H+<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">(aq)</span> at the anode<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">11</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Mechanism 1&2" height="185" src="http://www.wtin.com/media/16744/mechanism-12.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="460" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Al Electrode Reaction</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In the EC process involving aluminium electrodes, the following reactions occur at different electrodes and in solution:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Anode" height="120" src="http://www.wtin.com/media/16745/anode.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="373" /><span style="background-color: white;">There are various other species that dimeric, trimeric and polynuclear hydrolysis products of Al can also form<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;"><span style="border: 0px; bottom: -0.25em; font-size: 7px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">12,13</span></span>. These Al(OH)<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">3</span> flocs capture the dye molecules present in the solution by the following reaction mechanism<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">14,9</span>.</span></div><div class="left-image" style="border: 0px; float: left !important; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 11px; margin-bottom: 10px !important; margin-right: 15px !important; margin-top: 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;"><span style="background-color: white;"><img alt="Precipitation" height="200" src="http://www.wtin.com/media/16746/precipitation.jpg" style="border: 0px; margin: 0px !important; outline: 0px; padding: 0px; vertical-align: baseline;" width="312" /></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Electrocoagulation technology is also considered to be potentially an effective tool for treatment of colour from textile wastewaters with high removal efficiency and it rapidly removes the chromophores and by-products of dye solutions<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">16</span>. The removal efficiency is found to be dependent on the initial pH, the dye concentration, the applied current density, and the electrolysis time in the batch model<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">9</span>. The chemical composition of the aqueous solution, solution temperature, type of salt used to raise conductivity, presence of chloride, electrode gap, passivation of the anode, and water flow rate also have an impact on the removal efficiency and economic durability of a given EC application<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">17</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The electrocoagulation process has not been commercially successful due to the issue of electrode reliability and the lack of a systematic approach to electrocoagulation reactor design and operation<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">8</span>. However, this process is emerging and offers a lot of potential, especially for decentralised water-treatment facilities.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Both aluminium and iron, when used as anodes, offer advantages as well as limitations over each other. Wastewater treated with iron electrodes tends to develop a brown colour due to formation of ferric hydroxide, which often affects the aesthetics of water, and iron has higher electrode consumption than aluminium during electrocoagulation process<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">18</span>. Aluminium, on the other hand, has high coagulation efficiency but consumes more power than iron electrodes during the electrocoagulation process<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">18</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In this paper, we have investigated the efficiency of different electrode materials and their combination in the removal of disperse and reactive dyes from synthesised dye wastewater. We attempt to see whether a combination of iron and aluminium electrodes can be a better alternative to iron or aluminium electrodes, which are currently used individually.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Experimental</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Materials</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dye wastewaters were prepared from commercially available disperse and reactive dyes. For all dye wastewaters trials, the dye concentration was maintained at 250 mg/l. Disperse dye wastewater contained dye C.I. Disperse Blue 79 and Reactive dye wastewater contained Drimarene Navy HF-GN. Sodium Chloride was added to the dye wastewater to increase the conductivity to around 2000 µS/cm. Initial pH of dye wastewater prepared was adjusted to neutral (7.0 ± 0.2) using sodium carbonate and acetic acid.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Apparatus and Instruments</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">All the electrocoagulation experiments were conducted in a 5L borosil-make glass beaker. There were four electrodes used in each configuration. All the electrodes were made from plates with dimensions of 120mm x 100mm x 6mm. There were three different electrodes configurations used, ie. 1. Iron electrodes (two iron electrodes as anodes and two iron electrodes as cathodes); 2. Aluminium electrodes (two aluminium electrodes as anodes and two aluminium electrodes as cathodes); and 3. Combination electrodes (one iron and one aluminium electrode as anodes and one iron and one aluminium electrode as cathodes).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">All the cathodes and anodes were in parallel connection with the spacing between electrodes maintained at 5mm. A spacing of 25mm was maintained between bottom of glass beaker and the electrodes in order to allow magnetic stirring of dye wastewater to take place. The electrodes were connected to a digital DC power supply (Gwinstek PSW 80-27; 80 V, 27 A) and all experiments were operated in galvanostatic mode. The electrodes were connected as monopolar electrodes in parallel connection, ie. both anodes connected to the positive terminal and both cathodes connected to the negative terminal of the DC power supply. This electrode mode connection was selected as it offers the most cost-effective solution in terms of process economy, as studied by Kobya et al<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">10</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A UV-vis spectrophotometer (GBC UV/VIS 918) was used to measure dye concentration. pH and conductivity were measured by research-grade meter (Hanna HI4522, USA) and Chemical Oxygen Demand (COD) was measured using Lovibond COD Vario MD 200 instrument. Turbidity of dye wastewater was measured by turbidity meter (Hanna HI 88713, USA) and reported in Nephelometric Turbidity Units (NTU).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Methods</strong></span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">All the electrodes were washed before each trial in a freshly prepared solution containing 300 cm<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">3</span> HCl solution (35%) and 600 cm<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">3</span> of hexamethylenetetramine aqueous solution (2.80%) for 5 min, to remove all impurities from the electrode surfaces, and further with distilled water<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">10</span>. A magnetic stirring rate of about 350rpm was maintained throughout the experimental trial. In each trial, the dye wastewater volume used was 3.5L and the total time duration of the trial was 10 mins unless noted otherwise. The DC power supply provided the desired constant current (4A and 8A) to the electrodes by varying the voltage, which was recorded. All experiments were carried out at room temperature (30°C ± 2°C).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Conductivity of solution plays an important role in electrolytic processes and high conductivity can help achieve high current at lower voltages to keep power consumption low. Therefore sodium chloride was added to the dye wastewater to increase the conductivity to around 2000 µS/cm. pH was kept initially at neutral for all trials, as high colour removal efficiency is reported at neutral media<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">15</span> and also the size of hydrogen bubbles liberated at cathodes is minimum around neutral pH and thus is helpful in the flotation process<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">19</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dye removal was estimated by measurement of absorbance of initial and final dye wastewater after each trial in the UV-vis spectrophotometer. Absorbance of dye solution was measured at wavelength of maximum absorbance (λmax).</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Chemical Oxygen Demand (COD) was tested using standard test method ISO 15705:2002, also called the sealed tube method. The samples were first digested (oxidised) at 150°C for 2 hrs and then the COD was measured by photometric method using Lovibond COD Vario MD 200 instrument.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Results & Discussion</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Removal of disperse dyes</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Effect of Electrode Configuration on Removal of Disperse Dyes</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">All three electrode configurations showed colour removal efficiency in excess of 99%, as shown in Table 1. Disperse dyes are non-ionic dyes that are relatively insoluble in water at room temperature and have only limited solubility at higher temperatures<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">20</span>; thus, compared to soluble dyes, it is relatively easy to separate disperse dyes from dye wastewater. Aluminium electrodes offered better and faster colour removal than iron and mixed electrodes. Dye wastewater treated with iron electrodes shown a slight brown tint due to formation of ferric hydroxides<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">21</span>, although later most of it had settled down along with the sludge. Similarly Chemical Oxygen Demand (COD) removal was also higher in the case of aluminium electrodes and a maximum of 57% was achieved at 8A current. Turbidity also came down from 1315 NTU in initial disperse dye wastewater to nearly 1-5 NTU in treated wastewater in all electrode configurations. A combination of electrodes also was able to reduce maximum colour, high chemical oxygen demand and high turbidity at a lesser voltage requirement than aluminium electrodes. No brown tint of iron oxide was within visual observable range in combination-electrode-treated wastewater.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 1" height="242" src="http://www.wtin.com/media/16747/table-1.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="633" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Effect of Current on Removal of Disperse Dye</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The coagulation rate significantly increased with an increase in current and complete separation of dye molecules from dye wastewater took place in around 6-8 min. at 8A, compared to 12-15 min. at 4A, in all three electrode configurations. Current is the most crucial parameter for the electrocoagulation technique and hence an increase in current leads to an increase in the rate of release of ions and to a higher rate of hydrogen bubble formation<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">22</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Fig 1&2" height="524" src="http://www.wtin.com/media/16748/fig-12.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="517" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Removal of reactive dyes</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Effect of Electrode Configuration on Removal of Reactive Dyes</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It was clearly observed that iron electrodes are more effective than aluminium electrodes for removal of reactive dyes from reactive dye wastewater. With iron electrodes, colour removal efficiency of 98.3% and 99.5%, at 4A and 8A respectively, was achieved, whereas with aluminium, maximum colour removal achieved was 43.7% at 8A current. However, with combination electrodes, ie. two Al and two Fe, colour removal was 97.6% at 8A current. Similarly, iron electrodes led to higher reduction in chemical oxygen demand of dye wastewater compared to the other two configurations, ie. aluminium electrodes and combination electrodes (Table 2). A maximum of 61.5% reduction in chemical oxygen demand (COD) was possible with iron electrodes at 8A current.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Table 2" height="226" src="http://www.wtin.com/media/16749/table-2.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="588" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Effect of Current on Removal of Reactive Dyes</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">All the results showed that there is an increase in colour removal efficiency and a significant increase in the rate of coagulation with an increase in current. With iron electrodes, the colour-removal efficiency increased from 98.3% to 99.5% when current was increased from 4A to 8A. This change was observed in only 10 min. in the case of 8A current, compared to 15 min. with 4A current. Beyond this point, the removal of colour did not significantly change over time.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Similar results were obtained with aluminium electrodes and combination electrodes, with colour-removal efficiency increased from 37.8% to 43.7% and 95.3% to 97.6% respectively at higher current. Similar results were also obtained for reduction in chemical oxygen demand (COD) of dye wastewater, as shown in the Table 2. Increase in current leads to higher rate of release of metal ions and hence higher rate of coagulation. Another reason for the high rate of separation of reactive dyes from dye wastewater at high current is the higher production of hydrogen bubbles, which entrap the formed microflocs and help in flotation, thus leading to effective flocculation.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> </span><img alt="Fig 3&4" height="492" src="http://www.wtin.com/media/16750/fig-34.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="474" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Effect on pH of Dye Wastewater</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">An increase in pH was observed from neutral (7.0 ± 0.2) to (8.4± 0.4) during electrocoagulation trials. It can be explained by the fact that electrocoagulation process produces hydroxides, ie. Al(OH)<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">3</span> or Fe(OH)<span style="border: 0px; bottom: -0.25em; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; vertical-align: baseline;">3</span> in solution, which lead to increase in pH<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">23</span>.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Effect of Electrode Configurations on Voltage during Galvanostatic Mode of Operation</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The amount of voltage required to achieve constant current varied with different electrode configurations. Aluminium required a higher voltage to achieve the same current and hence led to higher power consumption. No significant change in the conductivity of dye wastewater was observed during the entire trials and it was constant around 2080 µS/cm.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Conclusion</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Electrocoagulation processes are found to give excellent dye removal efficiency, as high as 99.8% in the case of disperse dye and up to 99.5% in the case of reactive dye investigated. In the case of disperse dye, the turbidity removal efficiency was 99.9% when aluminium electrodes were used and clear treated water was obtained. Electrocoagulation also gave higher chemical oxygen demand removal efficiency, up to 57% in the case of disperse dye with aluminium electrodes and up to 61.5% in the case of reactive dye with iron electrodes.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Combination electrodes gave satisfactory results, giving higher colour removal efficiency and lesser brown tint than iron electrodes in the case of disperse dyes. Similarly, they gave higher colour removal efficiency at lower voltage (ie. lower power) than aluminium electrodes in the case of reactive dyes. Thus, combination electrodes (ie. one iron and one aluminium electrode as anodes and one iron and one aluminium electrode as cathodes) are found to have potential to be used in commercial electrocoagulation processes dealing with different kinds of dye effluent and offer scope for further investigation with other classes of dyes and validation in pilot-scale trials.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Acknowledgement</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">This study is a part of an R&D project “To Develop an effective and eco-friendly electroflocculation technique to treat wastewater effluent with high FOGs (Fats, Oils & Grease), metals and organic loads for the woollen industry”, sponsored by the Ministry of Textiles, Government of India.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">References</span></strong><br />1. Christie RM, Environmental aspects of textile dyeing, Woodhead Publishing Limited, 2007 191.<br />2. O’Neill C, Hawkes FR, Hawkes DL, Lourenco ND, Pinheiro HM, Delee W, Colour in textile effluents—sources, measurement, discharge consents and simulation: a review, J. Chem. Technol. Biotechnol. 74 (1999) 1009–1018.<br />3. Gao P, Chen X, Shen F, Chen G, Removal of chromium(VI) from wastewater by combined electrocoagulation–electroflotation without a filter, Sep. Purif. Technol. 43 (2005) 117–123.<br />4. Hopman R, Vander Hoek JPP, VanPaassen JM and Kruithof JC, The impact of NOM presence on pesticide removal by adsorption: problems and solutions, Water Supply, 1998 16(1–2) 497–501.<br />5. Marmagne O and Coste C, Color removal from textile plant effluents, Amer Dyestuff Rep, 1996 85(4) 15–20.<br />6. Christie RM, Environmental aspects of textile dyeing, Woodhead Publishing Limited, 2007 149-175.<br />7. Marmagne O, Coste C and Jacquart J-C (1996) Effluents decoloration. L'Industrie Textile 1278, 46-51.<br />8. Holt PK, Barton GW, Mitchell CA, The future for electrocoagulation as a localized water treatment technology, Chemosphere 59 (2005) 355–367.<br />9. Emamjomeh MM, Sivakumar M, Review of pollutants removed by electrocoagulation and electrocoagulation/flotation processes, Journal of Environmental Management 90 (2009) 1663–1679.<br />10. Kobya M, Bayramoglu M, Eyvaz M, Techno-economical evaluation of electrocoagulation for the textile wastewater using different electrode connections, Journal of Hazardous Materials 148 (2007) 311–318.<br />11. Un Umran Tezcan, Aytac E, Electrocoagulation in a packed bed reactor-complete treatment of color and cod from real textile wastewater, Journal of Environmental Management 123 (2013) 113-119.<br />12. Mouedhena G, Feki M, De Petris Wery M, Ayedi HF, Behavior of aluminum electrodes in electrocoagulation process, Journal of Hazardous Materials 150 (2008) 124–135.<br />13. Richens DT, The Chemistry of Aqua Ions, Wiley, Chichester, 1997.<br />14. Chithra K, Thilakavathi R, Arul Murugan A, Marimuthu C, Balasubramanian N, Treatment of Textile Effluent Using Sacrificial Electrode, Modern Applied Science, Vol. 2, No. 4, July 2008 38-43.<br />15. Sengil IA, Ozacar M, Omurlu B, Docolorization of C.I. Reactive Red 124 using the electrocoagulation method, Chem. Biochem. Eng. Q. 18 (2004) 391-401.<br />16. Wei MC, Wang KS, Huang CL, Chiang CW, Chang TJ, Lee SS, Chang SH, Improvement of textile dye removal by electrocoagulation with low-cost steel wool cathode reactor, Chemical Engineering Journal 192 (2012) 37–44.<br />17. Kuokkanen V, Kuokkanen T, Rämö J, Lassi U, Recent Applications of Electrocoagulation in Treatment of Water and Wastewater—A Review, Green and Sustainable Chemistry, 2013, 3, 89-121.<br />18. Comninellis C, Chen G, Electrochemistry for the Environment, Springer New York, 2010, P.no. 248.<br />19. Fukui Y, Yuu S, Removal of colloidal particles in electroflotation, AIChE J. 31 (1985) 201-208.<br />20. Broadbent A D, Basic Principles of Textile Coloration, Society of Dyers and Colourists, 2001.<br />21. Zongo I, Maiga AH, Wéthé J, Valentin G, Leclerc J, Paternotte G, Lapicque F, Electrocoagulation for the treatment of textile wastewaters with Al or Fe electrodes: Compared variations of COD levels, turbidity and absorbance, Journal of Hazardous Materials 169 (2009) 70–76.<br />22. Chafi M, Gourich B, Essadki AH, Vial C, Fabregat A, Comparison of electrocoagulation using iron and aluminium electrodes with chemical coagulation for the removal of a highly soluble acid dye, Desalination 281 (2011) 285–292.<br />23. Canizares P, Jiménez C, Martínez F, Rodrigo MA, Sáez C, The pH as a key parameter in the choice between coagulation and electrocoagulation for the treatment of wastewaters, Journal of Hazardous Materials 163 (2009) 158–164.</span></div></div>Unknownnoreply@blogger.comtag:blogger.com,1999:blog-2374997165792528822.post-72658155815993224902014-06-08T23:45:00.000-07:002017-03-01T03:24:34.703-08:00Eco-Friendly Dyeing of Polyester/Viscose Blended fabric with Himalayan Rhubarb (Rheum emodi) Root<div dir="ltr" style="text-align: left;" trbidi="on"><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Abstract</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">In recent years, the production of polyester fibres has been dynamically increased, accompanied by the wide use of polyester-cellulose blends. Viscose is the best yet complement for polyester in blends. In polyester/viscose blends polyester contributes strength, durability and dimensional stability, and viscose contributes absorbency, softness and handle. But the coloration of such blend creates problems because of the differential dyeing affinity of both the fibres. However, some synthetic dyes can be used but the process is very complex and also not friendly to the environment. Nowadays, as everyone is concerned about environmental safety and also aware of the carcinogenicity of some synthetic dyes, the use of natural dyes has emerged as an eco alternative. Hence, the present research has been made to assess the compatibility of natural dye obtained from Himalayan rhubarb (Rheum emodi)root with polyester/viscose blend using a high temperature high pressure (HTHP) dyeing technique. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Introduction</span></strong> </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The textile industry is not only one of the oldest but also continues to be one of the mainstays of the world economy. Textile products were created from natural, rapidly renewable and abundant sources for thousands of years, and then innovators introduced synthetic fibres to overcome some of the inherent limitations of natural fibres. Among the synthetics, polyester fibres fully dominated the market due to their versatility in use, excellent mechanical properties, cheaper price, ease of care, biodegradability, etc. Though it also suffers from certain drawbacks, the fact that the inherent drawbacks in its structure can be corrected by means of blending means it is still the most widely used textile fibre. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Blends of polyester with natural and regenerated cellulose have become very popular in apparel usage for the obvious reason of techno-economic considerations, including the low cost, durability, comfort and aesthetic values of such blended fabrics. Viscose rayon, also known as artificial silk, is a blend-friendly fibre and most frequently blended with polyester in blends. The selection of these two fibres ensures sufficient comfort, resulting mainly from the use of viscose fibres, and suitable mechanical properties such as the tensile strength characteristics of polyester fibre. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Due to the presence of two dissimilar fibres, coloration of such blends has always been a challenging job to chemical processors. Though a good number of synthetic dyes are produced commercially for dyeing this blend, the current worldwide awareness about pollution and effluent disposal problems created by the synthetic dyestuff industry has revived the interest of people in the age-old art of dyeing with natural dyes. There is an increasing desire in the textile industry, as well as among textile consumers, to develop and use eco-friendly methods of dyeing textiles. This concern for the environment has once again attracted attention towards natural dyes, which are eco-friendly as well as safe for human skin and have gained momentum not only for safety but also for the beauty of their colours and for their novelty. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Hence, keeping in mind the exceeding popularity and benefits of natural dyes, the present study was undertaken to dye polyester/viscose blended fabric with Himalayan rhubarb dye, using different natural mordants and testing the colour strength and colourfastness properties of dyed and mordanted samples. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Experimental Details</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Materials</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Fabric:</span> Pure white plain weave polyester/viscose (67/33) blended fabric with 92/66 fabric count and 0.23 mm thickness was used for dyeing experiments. </span><img alt="Himalayan Rhubarb (Rheum Emodi ); Plant Roots" class="right-image" height="209" src="http://www.wtin.com/media/15163/himalayan-rhubarb-rheum-emodi-plant-roots.jpg" style="border: 0px; float: right !important; font-size: 11px; margin: 15px 0px 10px 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="152" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Natural dye material:</span> The Himalayan rhubarb root was used as the dye source. It was purchased from the local market of Haldwani, Uttarakhand, India. The raw dye material was examined carefully to remove peripheral matter and then ground to coarse powder form in the grinder. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Natural mordants:</span> Six natural mordants, namelyIndian gooseberry (Phyllanthus emblica) fruit, belliric myrobalan (<strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Terminalia belerica) </strong>fruit, myrobalan(Terminalia chebula) fruit, pomegranate (Punica granatum) rind, tea (Camellia sinensis) leaves and walnut (Juglan regia) bark were used to obtain varying colour/shade and to improve the colourfastness of the Himalayan rhubarb dyed samples.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Procedure</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; line-height: 20px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">1. Preparation of Fabric for Dyeing</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The polyester/viscose (P/V) fabric was soaked in warm detergent solution containing 5ml liquid non-ionic detergent in 1 litre of water for 1 hour. The fabric was rubbed, kneaded and squeezed in detergent solution from time to time then rinsed with excess tap water to remove traces of detergent completely and dried in shade. Samples of 22cm x 11cm dimension were cut from the prepared P/V blended fabric for the dyeing experiments; each sample weighed 2.50g. The fabric sample was soaked in water prior to dyeing for 30 minutes to remove air from it for rapid dye penetration. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">2. Extraction of Dye from Natural Resource</span> </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The dye was extracted using an optimised method of extraction based on visual evaluation and colourfastness of dyed samples. The optimised parameters used for the extraction of dye from raw material are shown in Table 1. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><br /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Tab 1" height="116" src="http://www.wtin.com/media/15164/tab-1.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="598" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">3. Dyeing of P/V Sample </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Dyeing of polyester/viscose blended fabric was carried out in a high-temperature, high-pressure beaker dyeing machine using the optimised dyeing conditions given in Table 2:</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Tab 2" height="88" src="http://www.wtin.com/media/15165/tab-2.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="598" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">4. Application of Mordants </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">A constant amount (2g) of all the six natural mordants was taken and mordant solutions were prepared by adding two gram of each natural mordant in 50ml of distilled water, allowed to soak overnight, then boiled for 15-20 minutes and filtered. Mordants were applied with the help of three methods of mordanting namely, pre-mordanting, simultaneous mordanting and post-mordanting. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">5. Colour Strength (K/S) of Control and Mordanted P/V Samples </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The K/S value of control (sample dyed using optimised conditions without mordants) and mordanted polyester/viscose samples was determined by measuringsurface reflectance of the samples using a computer-aided Macbeth 3100 reflectance Spectrophotometer and ColourLab plus software. The reflectance values (R) were converted to the corresponding K/S values using the Kubelka-Munk equation [K/S = (1-R)<span style="border: 0px; font-size: 9px; line-height: 0; margin: 0px; outline: 0px; padding: 0px; position: relative; top: -0.5em; vertical-align: baseline;">2</span>/2R]. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">6. Colourfastness of Control and Mordanted P/V Samples </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Washing fastness test:The washing fastness test was carried out as per the standard test method IS: 3361-1979in a launderometer in which the samples were subjected to a rotary washing movement using liquid non-ionic detergent solution. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Rubbing fastness test: The fastness of dyed samples to dry and wet rubbing was assessed using a crockmeter as per the standard test method IS: 766-1956. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Perspiration fastness test:The fastness of dyed samples to acidic and alkaline perspiration was estimated using perspirometer as per the standard test method IS: 971-1956. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">Light fastness test:Light fastness of dyed samples was evaluated by exposing the samples to day light under prescribed conditions and fading was carried out as per the standard test method IS: 686-1957. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Results and Discussion </span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Colour Strength (K/S) of Dyed and Mordanted Samples</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The K/S values of the samples dyed with Himalayan rhubarb dye and treated with different natural mordants using three methods of mordanting are given in Table 3.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Tab 3" height="364" src="http://www.wtin.com/media/15166/tab-3.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="631" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It is evident from Table 3 that the highest K/S value (13.06) among all the mordanted samples was exhibited by walnut bark post-mordanted sample and second highest value (12.45) was exhibited by teapre-mordanted sample. In general, it can be observed from the results that the colour strength of the samples dyed with Himalayan rhubarb dye improved after mordant treatment using pre and post-mordanting methods. In case of simultaneous mordanting method K/S values were found to be decreased in comparison with control sample.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"> </span><img alt="Fig 1" height="275" src="http://www.wtin.com/media/15167/fig-1_479x275.jpg" style="border: 0px; display: block; margin: 0px auto; outline: 0px; padding: 0px; vertical-align: baseline;" width="479" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Colourfastness of Dyed and Mordanted Sample</span></strong> </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The mordanted samples were subjected to various colourfastness tests. The colourfastness ratings of P/V samples dyed with Himalayan rhubarb dyes after mordant treatment are shown in Table 4. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Washing Fastness</span></strong> </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It can be seen from Table 4 that the ratings for change in colour were found to decrease in all the mordanted samples as compared to control sample having rating 5, ie. no change in colour. Slight (4) or slight to no change (4-5) in colour was exhibited by most of the mordanted samples except myrobalan simultaneousmordanted and walnut bark pre and post-mordanted samples that exhibited noticeable to slight (3-4) change in colour. Colour staining ratings on cotton fabric were found to be improved in all the mordanted samples, with slight to no staining (4-5) or no staining (5) as compared to control sample with slight (4) staining. No staining (5) on P/V fabric was exhibited by both control and mordanted samples. According to Singh (2000), good washing fastness of the samples may be due to the reason that some of the natural dyes have a tendency to aggregate inside the fibre, thereby increasing the molecular size and hence exhibit good washing fastness. Complexing with mordants also has the effect of insolubilising the dye and making it colourfast. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Rubbing Fastness</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><img alt="Tab 4 1" class="left-image" height="647" src="http://www.wtin.com/media/15173/tab-4-1.jpg" style="border: 0px; float: left !important; font-size: 11px; margin: 15px 15px 10px 0px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="460" /><span style="background-color: white;">Both the control and mordanted samples were found to be fast towards dry rubbing, with fastness ratings being in the range of 4 to 5. On wet rubbing, noticeable to slight (3-4) change in colour was exhibited by Indian gooseberry, belliric myrobalan, myrobalan, tea and pomegranate simultaneous mordanted and tea post-mordanted samples however slight change (4) in colour was exhibited by Indian gooseberry, belliric myrobalan, pomegranate rind, walnut bark post mordanted and pomegranate simultaneous and myrobalan pre-mordanted samples as compared to control sample with slight to no change (4-5) in colour. Noticeable to slight staining on cotton fabric was exhibited by Indian gooseberry and belliric myrobalan pre mordanted samples similar to that of control sample however in other mordanted samples the colour staining ratings were improved. It is clearly evident from Table 3 that dry rubbing tests showed better results than wet rubbing test as it was having better fastness ratings. This may be because of the breakage of dye metal complexes into simple particles during wet rubbing (Gulrajani, 1993). </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Perspiration Fastness</span></strong> </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It can be observed from Table 4 that in case of acidic perspiration fastness the ratings of change in colour of the mordanted samples either remained same or decreased to slight (4) or noticeable to slight (3-4) change in colour as compared to control sample with slight to no change (4-5) in colour. The ratings of colour staining on both the adjacent fabrics were found to be either similar or improved as compared to control sample with noticeable staining (3) on cotton and slight staining (4) on P/V fabric. It is also evident from the results that in case of alkaline perspiration fastness, the control sample exhibited slight change (4) in colour and noticeable and noticeable to slight staining on cotton and P/V fabrics respectively that either remained as such or slightly improved in all the mordanted samples. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Fastness to Sunlight</span></strong> </span><img alt="Fig 2" class="right-image" height="456" src="http://www.wtin.com/media/15174/fig-2_487x456.jpg" style="border: 0px; float: right !important; font-size: 11px; margin: 15px 0px 10px 15px !important; outline: 0px; padding: 0px; text-align: center; vertical-align: baseline;" width="487" /></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The control samples dyed with Himalayan rhubarb dye exhibited very good light fastness (6) which was further improved to excellent to outstanding (7-8) in tea pre-mordanted and walnut bark post-mordanted samples. In general, the light fastness of samples dyed with Himalayan rhubarb dye improved after mordant treatment. This may be attributed to the presence of anthraquinone structure in Rheum emodi thatshows an increased resistance to light fading. According to Gupta (2000), the quinone based dyes exhibit exceptional fastness properties though dyes based on other chromophoric groups may not be so fast.</span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">The colour obtained by Himalayan rhubarbdyed and mordanted P/V blended fabric under optimized conditions ranged from brown to yellowish-brown. </span></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><strong style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white; border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Conclusion</span></strong></div><div style="border: 0px; font-family: Arial, Verdana, Helvetica, sans-serif; font-size: 12px; outline: 0px; padding: 0px; vertical-align: baseline;"><span style="background-color: white;">It can be concluded from the findings of the study that polyester/viscose blended fabric can be successfully dyed with Himalayan rhubarb dye with acceptable fastness properties. Application of mordants further improved the colourfastness to washing, light, rubbing and perspiration. The mordanted P/V blended samples exhibited good to excellent fastness to washing, rubbing, and light and moderate fastness to perspiration. Majority of the mordanted samples exhibited high K/S values in post mordanting method as compared to control sample. The colour shade developed on Himalayan rhubarb dyed P/V samples after mordanting ranged from brown to yellowish-brown. The colour obtained by Himalayan rhubarb dye was fast even in the absence of mordants, hence has a tremendous potential in textile dyeing industry and may gain significant place in the market on the basis of its good fastness properties, and plentiful availability in India.</span></div></div>Unknownnoreply@blogger.com