A Closer Look at Digital Textile Printing What printers need to know to get into the game By Toni McQuilken Mimaki TX500-1800B Digital printing on soft signage is huge in some parts of the world, and the market in the United States is growing rapidly. But printing on fabrics comes with a unique set of challenges that printers who want to add this skill set to their list of services will need to overcome. First and foremost, printing on fabrics requires having equipment that is made specifically for that purpose. And while machines that print on paper will accept most types as long as they are the right size, when it comes to fabric, you have to have the right machine for the right type. The biggest differentiator is whether or not you plan to print on fabrics that have stretch to them or not. But like anything else, there are exceptions. For example, if you only plan to use UV technology on vinyl fabrics—or vinyl blends—you can likely use your current machinery. That’s what Big Mountain Imaging did, according to East Coast Sales Manager Steven Saltzman. He noted that his shop uses UV or latex inks, but they stick to fabrics that have at least some vinyl in them. “Most materials that we print on, the ink sits on the surface, which gives bright, vibrant colors. When we print onto fabrics, the ink tends to absorb in, leading to muted colors,” he said. “We researched and found a variety of materials that have a blend of fabric and vinyl to them. This gives our inks the ability to reproduce vibrantly while giving our clients the fabric solution that they require.” That problem of inks soaking into the fabric is the second consideration that any printer looking to get into the market will need to be aware of. Using vinyl blends is one option, but it does limit the selection. Another option is to install equipment that can prepare fabrics for printing. The process puts a thin layer of a chemical coating on top of the fabric, which allows the ink to sit just on the surface, rather than soaking in. In most cases, the finished piece will then need to cure, usually using heat, to set the image in place. “The goal when direct printing is to get as much saturation without ink spreading in the fabric, which can cause poor image quality,” said Tommy Martin, director, Textile Business Development, Mimaki USA. Martin went on to note that printers who want to get into this side of the business will need to be very aware of each of the fabrics they offer, as each one will require its own unique blend of coatings to get the ink saturation and color exactly right. “Always test new fabric lots for consistency in type, coating and overall performance before running,” he cautioned. “Profiles should be specifically created for each fabric so that colors will not shift and the density is consistent. Once profiles are completed and tested, save the test pattern swatches for future reference. Keep in mind that fabric is not a perfect surface on which to print—it wants to absorb ink and it is not smooth. These two factors are what cause a lot of issues. There is no one profile for all fabrics.” “Simply put, textiles are not made for the purpose of being printed on,” agreed Oliver Luedtke, the head of global PR for Kornit Digital Europe GmbH. “They will soak in liquids, so if you put a big drop of yellow ink on a black textile surface, it will sink into the fabric and visually disappear. That’s why textiles require a pretreatment before printing, and usually this is an external step that requires manual handling and drying before the fabric or garment even goes to print.” Complicating matters even further, direct-to-print systems aren’t the only option, either. Sublimation is another printing method that lends itself well to printing on fabrics as well. The fabrics used in this method are often polyester, rather than vinyl, and in many cases come precoated and ready to print. “When selecting a textile on which to print, it is important to ensure that it is compatible with the particular ink type you plan to use. For sublimation/disperse, select a polyester fabric that has a direct print finish coat. This will insure that you have sharp crisp images with brilliant color. For solvent or latex, select a textile that is compatible with the ink type you are using. There are some fabrics that have a 12 Wide-Format Imaging | July 2015 MyPRINTResource.com
Wide-Format Imaging July 2015
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