Over the past few years, there’s been a lot of talk about fabric, a.k.a., textiles, as an imaging medium. Customers like fabric because it’s perceived as more elegant or high-end than other media, plus it’s lightweight, making it easier and more economical to ship and deploy on-site. The question now is whether or not technological improvements are being made in the printing process—from the printer to the inks to the fabric itself—that will allow more print shops to offer fabric as a regular part of their primary product mix. The answer is a tantalizing yes and no.
Direct fabric printing systems are getting better all the time, but the most common method is still dye-sublimation transfer printing. (Image courtesy of Mimaki USA)
DYE-SUB, DIRECT AND INKJET-RECEPTIVE
Dye-sub is still the most common way to image fabrics. The image is typically printed in reverse on a transfer paper then transferred to the fabric using heat and pressure. The ink sets into the fabric, making it more water-fast than printing directly to an inkjet-coated fabric. Dye-sub retains the hand or feel of the fabric and produces vibrant images. It can also be washed and re-used.
The most recent development in dye-sub technology has been the advent of direct-to-textile printers that use disperse-dye inks, such as the D-Gen Telios, EFI’s VUTEk 3360 Fusion, DigiFab Systems’ StampaJet I-64 and Mimaki’s TX2-1600. Instead of using a transfer process, these printers typically use a fixation element to set the disperse dye inks into the fabric. Unlike traditional dye-sub, which can image to untreated fabrics, direct textile printers use fabrics that have been chemically treated to accept the ink.
Currently, all direct-print textile printers use aqueous disperse-dye inks. The next logical step, and one that could give traditional dye-sub a run for its money, is a solvent disperse-dye ink system for direct-print textile printers. Solvent inks dry quicker and provide more durability, but do not provide the same image quality. However, continual improvements in solvent ink technology have brought the image quality closer to aqueous.
“I’ve seen some phenomenal solvent dye-sub prints lately. The knock on solvent in the past was that the printers didn’t provide the color gamut or resolution needed. Now, companies like HP and EFI/VUTEk have made significant improvements to their solvent printers, and they’re producing a higher-resolution print,” says Scott Fisher, owner of Fisher Textiles, Indian Trail, N.C.
Solvent inks also provide greater outdoor durability. Aqueous dye-sub is intended mainly for indoor use or very short-term outdoor applications, like special events. Aqueous inks simply don’t inhibit UV rays like solvent or UV-curable inks.
(Image courtesy of Fisher Textiles)
“Transfer paper cockling is the biggest issue a printer encounters when they try to get those deep, rich colors, because they load up the ink and the paper can’t handle it,” says Fisher. “Because solvent ink dries faster, cockling is not as much of an issue.”
Thanks to improvements on the printer and ink side of the equation, traditional dye-sub has progressed and provided additional application options. Though only aqueous direct-print textile systems are currently available, expect a rash of announcements about solvent systems in the coming year or so.
“The key ingredient will be in the ink, not necessarily in the textile or a coating applied to the textile,” adds Fisher.
As a result, traditional dye-sub’s stranglehold on the fabric graphics market should loosen a bit over the next few years. Over time, Fisher expects that dye-sub will still represent more than 50 percent of the fabric imaging produced by print shops, but the total volume should continue to increase in relation to other imaging media, like vinyl.
“Fabric is infiltrating printed vinyl applications. Vinyl is a huge market, of course, and there will always be a lot of vinyl printing because it has attributes fabric doesn’t. However, there are places vinyl is used where fabric is better, such as banner stands for both point-of-purchase and trade show applications. This substitution is an ongoing trend, along with the printer and ink manufacturers finding different ways to print textiles, which will continue to grow the textile market,” says Fisher.
Fisher Textiles also offers a line of coated fabrics that can be printed directly with aqueous, solvent and UV-curable inks. Though companies that are coating fabrics for direct printing admit that this method may never provide the same qualities as a dye-sub fabric graphic—the vibrancy, feel and wrinkle-free attributes of dye-sub—the coatings are continually being improved.
One of the big benefits of fabric is its versatility. It provides a certain high-end ambience that other printable materials don’t, plus it’s lightweight, making it easier and less costly to ship.
“The number one problem with printing fabric directly with solvent and aqueous printers is that it doesn’t look or feel like dye-sub. Since you’re talking about dots hitting the fabric, as opposed to being embedded in the fabric itself, dot gain is the issue. It’s difficult to get a nice, solid black or other dark color,” explains Jeff Leto, product manager for LexJet, Sarasota, Fla. “Fabric, by its very nature, is a sponge. It sucks up the ink, which makes the images look muted. The inkjet coatings detract from the look and feel of the fabric because you’re basically filling holes. So, that’s something we’ve been working on recently: a fabric that images more like dye-sub.”
LexJet’s most recent entries for fabric printing are built on the latest coating technologies, including one with coatings optimized for both solvent and UV-cure ink technologies. Leto adds that LexJet plans to release a line of similar fabrics compatible with aqueous printers, like the HP Z series, Canon’s iPF series and Epson’s 7880, 9880 and 11880 printers.
Fisher reports that his company has seen a marked decline in the aqueous market as many of their customers have either moved to solvent and UV-curable technologies, or have converted their aqueous printers to a disperse ink system for dye-sub.
“Direct-print coated fabrics for aqueous pigmented inks haven’t gone mainstream, at least for us, because the inkjet coating technology is relatively expensive, it changes the hand of the material, making it stiff and the water-fastness can be an issue,” says Fisher. “With direct-print UV-curable and solvent textiles getting better, that’s the way it’s going, and the coated fabrics are an excellent alternative for print shops that don’t have dye-sub or direct dye-sub capabilities.”
Fisher adds that the company’s inkjet-receptive coatings are designed to retain the original feel of the fabric as much as possible. Fisher Textile’s line of inkjet-receptive fabrics is the same the company sells for dye-sub, but with a light treatment for solvent inks.
For UV-curable inks, Fisher says, “It can be difficult to handle textiles on a UV-curable printer due to the vacuum systems on the machines if they don’t have a roll-to-roll system. A paper-backed fabric will alleviate those handling and feeding problems and help control the fabric more like a paper, but it obviously adds cost and a step in the process. The other option is to use the solvent-compatible materials. The treatment or coating restricts how much the fabric breathes, so the vacuum system won’t suck the ink through. The coating also aids in the adhesion of the ink, enhancing the color and resolution of the image.”