By Olivia Cahoon
A variety of textiles are constructed for and used in the digital printing process. With advancements in today’s print technologies, substrate composition, and ink and coating chemistries, print service providers (PSPs) looking to dabble in fabric printing can work with their existing UV or latex device thanks to fabric optimized for these ink sets.
Fabrics designed for UV and latex printing technologies are found in applications like décor and garments. Advantages of using these fabrics when paired with UV and latex ink include UV resistance, durability, and a soft hand when treated with a coating.
Above: Example of a UV/latex printable fabric from Agfa Graphics portrayed in a trade show environment.
Every ink set offers its own benefits and printing to textiles optimized for UV or latex printers is no different. These fabrics are designed for fire resistance, weatherability, and sustainability while requiring minimal preparation.
In several cases, PSPs work with fabrics optimized for UV and latex printing to achieve a decreased turnaround time on specific applications. “The continuous growth for print on demand with 24 hours or less turn time on finished products can be easily met with latex and UV inks printed on properly coated fabrics achieving beautiful results,” says Mike Compton, product marketing manager, Top Value Fabrics.
Compared to two-step dye-sublimation processes, “it’s easier to produce short runs with UV and latex inks, and it takes less time to produce finished goods in small quantities,” agrees Gary York, wide format product manager, Agfa Graphics.
With UV and latex, PSPs can print directly to the fabric—saving time and money, explains Jason Amato, print production manager, Dietzgen Corporation. UV ink dries quickly, requires low energy to cure, and produces precise images. “Virtually any material is printable with UV technology. The inks are lightfast and as a bonus, they are UV resistant,” he adds.
“One of the great benefits of printing with UV inks is the quality of backlit graphics they can produce. UV inks tend to create more vibrant, colorful backlit images.” explains Paul Grider, director of product development, Dazian.
Latex is an environmentally friendly option that dries quickly and produces no hazardous vapors. Amato says it also resists solvents used in cleaning products and adheres to a variety of textiles for indoor and outdoor use. This is especially important for products that require regular washing, like garments or bed linens.
Pigments in latex ink offer improved lightfastness compared to dyes. According to Ann Sawchak, partner, PremEx Solutions, this is beneficial for items like curtains and outdoor cushions exposed to prolonged natural lighting.
A variety of fabrics are used with UV, latex, or UV and latex ink technologies depending on the fabric’s end use. Polyester is a popular choice due to the variety of applications it can be utilized for. However, other fabrics like canvas, cotton, and linen are also compatible.
“UV-curable printers have the benefit of printing to a range of media, and therefore both coated and uncoated polyester fabrics are compatible with this print process,” shares Sharon Roland, advertising and PR manager, Fisher Textiles. Polyester is often selected for outdoor applications and retail signage that requires added durability.
UV and latex printers work well with polyester, poly/cotton blends, and natural fibers. According to Amato, the only limitation of UV fabric printing is the ink’s decreased flexibility and increased brittleness after drying. “An ink set should be flexible enough to print on textiles without flaking or cracking when creasing the material,” he suggests.
When printing with latex ink, Kara Work, product manager, S-One Holdings Corporation, recommends a full polyester fabric specifically optimized for latex inks.
Fabrics with a considerable amount of stretch can cause challenges with UV or latex technology. “They have issues going through the output feed and take up rolls and can cause improper imaging,” warns Eric Tischer, president, Verseidag US. Stretchy materials, like knit fabrics, are prone to curling during printing and may require the use of a sticky belt or print blanket.
Coated textiles are preferred for latex printing to optimize the ink’s performance. Fabrics used for UV printing don’t necessarily require a pretreatment. Most manufacturers use a proprietary coating on textiles to ensure compatibility across various ink types, explains Amato.
“Most fabrics designed for latex or UV inks are coated as the inks are applied directly to the fabric and need a flat, firm surface to bond to. Uncoated fabrics tend to be too soft and can move or shift during the printing process,” advises Grider.
Kylie Schleicher, product manager, Ultraflex Systems, Inc., says that while fabrics for UV ink typically don’t require specialized pretreatment, fabric used with latex ink does need a proprietary coating. “The specialized coatings are needed for latex printable fabrics to ensure maximum durability and scratch resistance,” she adds.
Fabrics designed for latex inks are typically treated with a technology proprietary to the manufacturer that binds the latex ink to the fabric’s surface, shares Work. “It provides an enhanced bond between the latex ink and the fabric, allowing for crisp lines, fine text, and beautifully nuanced images.”
With a pretreatment, Sawchak says fabrics optimized for latex printing offer improved results for both wet and dry crock ratings, preservation of the fabric hand throughout the process, and an expanded color gamut that broadens an achievable color range. “The pretreatment is not always necessary if the fabric is for one-time use, or if the product will not be sat on, washed, or rubbed against,” she adds.
Jeff Mills, TexStyles fabric manager, Beaver Paper & Graphic Media, Inc., finds most polyester and natural fibers are pretreated for durability although natural cottons, burlaps, hemp, and bamboo feature adhesion without coatings. For the most accurate results, he suggests testing fabric by latex media certification teams.
Compton advises against woven fabrics not specifically coated for UV or latex technology. Most woven fabrics differ from coated knit fabrics and don’t stretch with the inks or fray on the edges, which requires hot knifing or laser cutting to seal the edges. He also recommends PSPs work closely with fabric suppliers to understand the characteristics and coating technology for their print process and applications.
Coatings also enhance the graphic’s quality to ensure the image is sharper and clearer, continues Edwin Ramos, national sales manager, SEAL & GBC Wide Format, ACCO Brands. For example, some coatings enhance and protect for indoor and outdoor applications while providing wrinkle resistance, a soft drape, and precise images.
Grider points out that coatings can also mimic the soft hand typically associated with dye-sub transfer processes. PVC or silicone coatings in particular, in addition to the mount of coating used can create a soft hand feel.
Finally, other coatings like acrylic and polyurethane can help with light diffusion for backlit graphics and light blocking for blackout graphics, suggests Grider.
While print providers invest in digital printing to produce customized short runs of textiles, fabric quality and wearability is just as important as appearance. To achieve maximum wearability, a number of features are necessary in regards to the fabric and the ink set.
According to Amato, pre-coated textiles are more receptive to ink, withstand multiple washes without losing color, and offer increased wearability. Ink formulation also plays a large role in wearability with some OEM ink sets containing additives to improve durability and feel. “For example, UV inks must contain a flex agent to achieve a soft feel and remain durable. The flex agent allows the material to curl without flaking or cracking the ink,” he explains.
Fabrics optimized for latex ink offer a soft hand and produce high-quality graphics while UV printed fabrics can be printed at high densities and create eye-popping graphics, says Schleicher. She shares that UV optimized fabrics can lose their softness since the UV ink sits on top of the surface and isn’t absorbed into the material.
Fabric softness typically depends on the fabric’s quality and coating. “Fabrics optimized for UV and latex inks can offer both fantastic visual quality as well as a soft hand,” agrees Compton. “The newest generations of UV and latex inks offer much more flexibility, stretch capability, and softness when printed on properly constructed and coated fabrics.”
To ensure a quality feel and appearance, PSPs should avoid fabrics not optimized for printing with UV or latex inks. “Without the coating, colors are likely to bleed and will not result in very high-quality graphics,” admits Ramos.
Applications play a large role in the selection of fabric for UV and latex printing. This is especially true for fabrics requiring a long life expectancy outdoors. “You need a fabric that stands up to UV rays and the elements,” explains Ramos. Fabrics optimized for UV or latex inks typically have properties to safeguard against the outdoors including water resistance, UV resistance, anti-wrinkling, and protection against wear and tear.
Technology and fabric pretreatments also rely on the application’s end use and finishing needs. According to Compton, fabrics specifically coated to the PSP’s immediate need are critical, especially based on end uses like backlit, front lit, or dimensional stretch for silicone edge graphics (SEG) framing systems. For example, in fine art reproduction, poly/cotton canvas blends are selected for the stretchability required for framing.
Latex inks are traditionally used for banners, wraps, and retail signage, but are also a cost-effective solution for short runs of blended and cotton apparel. Recently, Tischer sees latex inks widely used in interior décor and window treatments. Due to the ink characteristics and lack of odor, he believes latex inks are ideal for interior applications and can be used for window fabrics and wallcoverings to décor.
Digital print is making headway in a variety of fabric-based applications like apparel, home décor, and SEG graphics. PSPs use UV and latex inks to create eye-catching printed fabrics without the need to purchase a separate printer and utilize transfer paper or heating presses. This allows them to save time, costs, accelerate speed to market, and try their hand at textile printing.
Jul2018, Digital Output