TEXTILES.ORG
By Maura Keller
As with many industries, technological advancements continually evolve the way fabric graphic professionals do business. From innovative printer technology to significantly improved ink disbursement, new advancements are revolutionizing the industry as a whole.
According Julie Gederos, product manager for Roland DGA Group, sublimation is still the primary technology of choice for today’s fabric graphics applications. However, new trends are opening up traditional fabric markets to other technologies.
“For example, the interior décor market is going digital and eco-solvent inkjet printers are now being used for applications such as artwork, photographic reproductions, wall graphics and borders,” Gederos says. “These elements complement traditional fabric décor items such as upholstery and window coverings, making an eco-solvent printer an attractive addition to businesses serving this market.”
As Gederos explains, what makes the revolutionary eco-solvent printing so attractive is the versatility of the platform. “Now, when designing any commercial or residential space, custom lettering, wall murals and personal photos can all be displayed as wall graphics,” Gederos says.
Today’s eco-solvent printers are available with a variety of extras, from integrated contour cutting for creating graphics of any shape to specialty inks such as white, light black and metallic silver that add dramatic impact to graphics. “An eco-solvent printer can also take a fabric business in new directions—producing everything from banners, signs and vehicle wraps to labels, decals, package prototypes, POP and more.”
Ideal inks
As Paul McGovern, national sales manager for industrial products and textile apparel at Mimaki explains, today’s inks for fabrics vary according to the substrate materials used. “There is a variety of dispersed dye, reactive, pigmented water-based, and acid dye inks for digital inkjet printing of textiles in the apparel, home furnishing, soft signage/banner and fashion-based fabrics,” McGovern says. “Each ink has its own chemistry and fixations processes for printing on the various materials/fabrics found in the textile marketplace. Digital inkjet technology is widely used today in the proofing, sampling and short run production environments for design and development purposes prior to large rotary press printing.”
As the technology evolves, sublimation and eco-solvent inks are the two primary options used for fabric applications. “In the graphics market, water-based direct dye inks are the ideal choice for high-quality printing,” says Chris Howard, vice president of North America marketing and sales at Durst Image Technology U.S., in Rochester, N.Y. “For other applications, such as home furnishings or apparel, generally an acid-based ink set is what is needed for the longevity factor.”
Color gamut and durability are other key factors when identifying the best inks to use. “When you are talking about fabrics, you are talking about a backdrop that tends to mute the colors you are printing,” Gederos says. “As a result, you need to use inks with a wide color gamut that will give you the dramatic contrasts and vivid, rich colors demanded for high-end fabric graphics. Sublimation inks remain unequalled in this regard, followed by eco-solvent inks.”
According to Dan Barefoot, owner at Graphics One, one of the new trends in the market is water-based environmentally safe inks such as SEPIAX and HP’s latex ink. “SEPIAX ink can print on virtually any substrate, including fabrics, without coating, as long as the surface temperature can be heated to 55 degrees Celsius,” Barefoot says. “This is a long-term movement, which will offer many other types of inks in this same class.”
Graphics One is also seeing far more water-based pigment inks, which do not need special coatings for natural fabrics such as cotton. “Over the past few years there have been some ink companies that are producing inks without binders, which then need to have a coating on the substrate in order to properly bind to the fabric,” Barefoot says. “Our inks do not need coating and we believe this is the trend for other manufacturers as well.”
New innovations in printers
Today’s fabric graphics printers have far surpassed the printing technology of just a few years ago. Here’s why: Recent advancements in print head and ink technology continue to enhance production speeds and color quality. “State-of-the-art printers today well outpace those of even a few years ago while delivering image quality that meets the highest standards for high-end customers, even in the fashion, entertainment and retail industries,” Gederos says. “Sublimation printers generally do one thing—they print. Finishing processes add extra steps and equipment to the workflow.”
So while many fabric graphics businesses rely on sublimation, they may benefit from the versatility of today’s eco-solvent devices. As Gederos explains, with eco-solvent technology, short production runs are easy to handle because of the queuing capabilities of the RIP. Integrated specialty inks and contour cutting streamline the workflow and eliminate manual processes. These features both expedite production and increase profitably. As a result, shops can capture revenues from work they previously outsourced or turned down.
“Roland printers are designed for versatility, though they are engineered to be complete solutions with dedicated RIP software and specifically formulated ink sets for each model. This tight integration allows the user to optimize the platform, ensures color consistency and preserves the long-term performance of the printer,” Gederos says.
The productivity of Durst’s platforms is one of the key factors in the advancement of direct printing onto fabrics. “This allows for our customers to manage larger campaigns while keeping their operating costs down,” Howard says. “We also have introduced the Kappa, which is a direct printing device that can use acid, reactive or water dye-based inks for very high production applications, fundamentally replacing analog print technologies. The Kappa can produce up to 6,000 square feet per hour with excellent print quality.”
Over the next few years Barefoot is expecting fabric printers to be able to have dual ink sets available from one printer. “This could include either eight or 12 color machines where a user might have either four or six colors per channel,” Barefoot says. “One channel could offer dye-sub ink and the other could offer a pigment fabric ink.”
So, can multiple print methods, multiple fabrics and multiple inks be used on one machine? Or are today’s printers limited to one type of printing? According to McGovern, some digital textile printers are fabric specific and decisions have to be made on what type of ink is the primary and which is secondary (80/20 rule) because the flushing procedures for switching out inks becomes expensive, time consuming and changeovers can be troublesome with ink residue in lines and colors muted until flush is fully removed.
“Mimaki used to offer ‘duel’ ink printers for the reactive and acid inks on the TX2 design studio model, but now we have strategically started manufacturing more of the higher speed production based single ink type printers,” McGovern says. “Mimaki just introduced a new TX-500 printer capable of 1.8 meter width printing with speeds in excess of 150 m2/h. The TX-500 is the fastest inkjet printer offered by Mimaki today.”
As McGovern explains, print speeds have increased because the piezo print head technology has improved, offering more nozzles, faster firing speeds up to 30 kHz and larger 53mm head plate designs to lay down more ink for producing color images on transfer paper or fabrics. “Traditional Epson piezo heads still used today have limited head height and jet firing speeds,” McGovern says. “Again, ink changeovers can be time consuming and cumbersome but media changeover can be accommodated with more advanced media/fabric material handling devices on the printers used to uniformly control feeding, provide accurate tracking and take up roll advancements found on most digital textile printers in this marketplace.”
Embracing
dye-sublimation
Dye sublimation is gaining more market share in the soft signage and trade show display sectors of the fabric graphics business. McGovern says this is due to the overall benefits offered for using these fabrics and materials for indoor use or short-term outdoor exposure in producing flags, banners, booth graphics and apparel sports products. “The lightweight properties of fabrics in relation to shipment, the environmental aspects, the ‘elegance and appeal’ of the fabric display over conventional polymer-based film products traditionally used are very attractive to the hospitality, home furnishing and retail industries,” McGovern says. “A new, exciting dye sublimation market is for ‘back lit’ LED panels used in signage that offer the brightness and wider color gamut of dye inks instead of the conventional film products offered today. Most fabrics will easily stretch and snap into LED light boxes and provide a higher quality color image for many sign and graphic applications.”
Gederos believes that dye sublimation is going to dominate the industry for years to come, because of the expansive color gamut of the inks and the soft hand of the finished graphic. However, Gederos says complementary technologies, such as eco-solvent printing, are playing a greater role in the market for fabric graphics because of their versatility and the simplicity of the workflow. “Remember that sublimation is an equipment-intensive process with a multi-step workflow,” Gederos says.
“Direct-to-fabric sublimation printing is still in its early stages, so most of the graphics today are still being produced through a transfer process involving coated transfer papers, stand alone heat presses and skilled labor to get to the end product.”
Chosen fabrics and processes
Each of the various types of printing processes require unique fabric options. For example, sublimation requires a white polyester or polycoated fabric, while eco-solvent fabrics are treated with coatings that are receptive to the ink.
Mimaki separates their business based on the fabric material requirements for either apparel or sign and display markets. Both these markets use digital inkjet printing but the ink set varies due to the inks and finishing processes used in the fixation of the dyes to the fabrics. As McGovern explains, silks used in prototyping and samples for the fashion industry use the acid inks that require a steamer to fixate the inks permanently on the silk and then have a washing process to finish. The same acid-based inks are used to color nylon materials.
“Reactive inks and pigmented water based inks are used primarily for cotton fabrics and require a heat fixation/drying process,” McGovern says. “The digital printers are capable of jetting different ink types, but selection of each type should be according to the application and textiles used. Some materials like spandex and Lycra™ require a special ‘sticky’ belt mechanism to keep the fabrics from stretching or moving during printing.”
Barefoot adds that today’s technology is focused primarily on polyester printing, whether it is coated or uncoated. “With the new inks and new printing technologies we believe there will be a tremendous growth in printing on virtually any fabric with no pre-coating required,” Barefoot says. “This change is already occurring and as users begin to understand the capabilities of these inks and printheads the market will expand even at a much higher rate.”
And because of the variable imaging and color matching of inkjet digital printing, larger and faster printers are being manufactured to meet the larger volume and widths of textile customers needing this type of low-to-medium scale production while offering them the quality of a production press output. “Most digital printers started out in design studios and classrooms to teach and instruct how to produce prototypes, samples and mock ups of small lots of printed fabrics for either fashion or home furnishings prior to rotary press printing,” McGovern says. “Know and understand the type of textile market your organization is capable of serving and producing prints.”