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.
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.
Economics vs. Capacity
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.
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.
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.
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.
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.
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.
Ignored Potential
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.
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.
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.
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.
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.
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.
Learning Curve
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.