By Cassandra Balentine
Dye-sublimation (dye-sub) printing, using either transfer or direct methods, is a popular process for printing to certain textiles and rigid media. For textile printing, dye-sub involves turning ink into a gaseous state with the use of heat to infuse the fibers of the media. With the increased demand for digital textile printing, the spotlight on dye-sub attracts new developments in terms of printing and finishing equipment, media selections, and ink.
Dye-Sub Ink Trends
The dye-sub process is known for its soft hand and brilliant output. However, there is always room for improvement. Tweaks in ink formulation and the development of new color options, like fluorescents and high-density blacks, enable higher quality, expanded gamut, and new application possibilities.
Ink manufacturers and their chemists continue to find new ways to spread innovation with the help of the latest technology. Matt Gusse, VP sales and marketing, Advanced Color Solutions, Inc., says a rebirth of optional colors, such as fluorescent/neon, spot colors like violet or orange, light blacks, and high-density black, seem to be making more of a push than in the past.
“A decade ago, fluorescents were very tough to find. They were used in limited applications such as costumes, safety, and entertainment,” he recalls, adding that today, bright colors are requested more. “Sublimation shops around the country and globe are requesting sample prints and information on how to obtain or hit these colors and what they have to purchase to do so. The requests result in the ink manufacturers delivering a quality, stable product.”
Michael Pender, president, Supply55, Inc., admits to a small but growing demand for neon dye-sub ink, noting that pink and yellow appear to be the most popular colors.
High-density black inks are another innovation. “The recent introduction of rich, high-density black ink plays an important role in production of apparel and signage products,” says Tim Check, product manager, professional imaging, Epson. Not only do they produce better blacks and richer tones; the increased contrast makes colors appear more vibrant.
Improvements in RIP software enable a range of dye-sub inks such as lighter shades of black for better shadow and mid-tone detail; light cyan; and light magenta in six- and seven-color systems, explains Ed Michaels, product manager, dye-sub textiles, STS Inks. “Orange and green are also available for nine- and ten-color systems. Fluorescent inks are reemerging as spot and brighter colors integrate into eight-color systems producing vivid light greens and bright pinks,” he offers.
According to Jack Papaiacovou, VP/GM, Hilord Chemical Corporation, a six-color system is beneficial to achieving smooth transitions and high resolutions at the lower tone areas. “In the same fashion, the use of light black in the system would allow the generation of smooth transitions in the gray areas where pure black is required.”
Improvements in dye-sub ink dispersions and carriers also have a substantial impact on the stability, continuous jetting, and the overall performance of dye-sub ink currently being used, says Michaels. “New formulations meet the demands of printer manufacturers and different printheads,” he explains.
Marco Girola, marketing specialist, Kiian Digital, points out there is also increased attention on eco-friendly products in terms of inks and fabrics, but also a waterless process with lower energy consumption.
With advanced inks, print service providers (PSPs) offering dye-sub applications benefit in a variety of ways, including improved productivity, a wider color gamut, and efficiency. High-density ink options help improve productivity.
Tony Cox, business manager, Sun Chemical Corporation, suggests that the new generation of dye-sub inks give brighter and stronger colors complemented by black inks with a higher density. “These features can allow the printer to use shorter sublimation times, which increase productivity. They can also be used on reduced weight transfer papers, which offer significant cost savings.”
Lily Hunter, product manager, textiles and consumables, Roland DGA Corporation, adds that because high-density dye-sub inks have less water in their formulations, they dry quickly on the transfer paper to speed up workflow.
Rob Almstrom, founder, American Print Consultants LLC, agrees, adding that high-density inks facilitate faster printing by reducing the amount of liquid being deposited on the carrier, reducing ink drying time, and preventing issues with stamping and artifacts caused during media take up.
He says the inks can also decrease the amount of cockling in the paper during printing, reducing the need for maintenance and lowering rework rates. “The same properties can also help reduce manufacturing costs, allowing lighter weight and less expensive papers to be utilized more effectively.”
The availability of fluorescents, spot colors, and light inks expand the print gamut, leading to different applications. Michaels believes that a varied ink palate allows users to expand into markets once only served by eco-solvent or pigment-based printing systems. He says dye-sub has expanded into grand format banners and backlit display products and that better and darker black dye-sub inks have helped the transition away from solvent.
Tommy Martin, product manager, textile and apparel business development and marketing, Mimaki USA, Inc., says expanded ink sets augment the dye-sub color gamut, enabling an end product with a more photorealistic look. However, he admits that these expanded colors have a specific purpose that not every customer needs. For example, if a customer is producing active sportswear and the like, they will be looking at fluorescent colors and possibly spot colors, while someone producing photo throw blankets might need light colors to help reproduce an image more like the original photo when transferred.
Advancements also help to improve the dye-sub process in terms of efficiency and lower costs. “This is partly due to the fact that technologies in both equipment and consumables have become more refined as a result of the rapidly growing demand. Also spurred by this growth are innovations such as inks with higher dye loads and new pigments for fluorescent and other special effects,” explains Almstrom.
The characteristics of improved ink for transfer printing include fast drying on paper, higher prismatic color performance, and better ink jetting performance—specific to the type of printhead, suggests Martin. “Printing with inks that are optimized to the specific type of printhead means fewer maintenance issues, less downtime for service, and fewer printhead replacements,” he adds.
Regardless of ink trends, the digital dye-sub process is well suited for particular applications, but not a fit for others. Apparel, furnishings, and soft signage are among those primarily targeted by dye-sub. However, the process is not limited to textiles and works well on rigid materials as well.
Check says applications that benefit most from high-density black inks include fashion apparel, because the increased contrast with a bolder black results in colors appearing more vibrant; sports apparel, since a rich black produces sports jerseys that are easier to see and identify team logos, numbers, and names; and backlit signage, because with darker blacks, less light is transmitted through the fabrics, resulting in a graphic with more vibrancy and pop.
Expanded gamut offerings also allow for better fine art and photographic quality output with dye-sub processes. “When properly profiled and used with your RIP software, adding light blacks or even light-light blacks create flesh tones and photo-realistic imagery with results once thought unachievable with dye-sub,” adds Gusse.
Michaels adds that the availability of 104-inch dye-sub printers paired with 125-inch calender presses allows for the production of grand format signs and banners as well as photographic-quality backdrop scenery for theatrical productions and trade shows.
While a variety of applications are suited to digital dye-sub, it is important to remember that the process is limited in terms of material capability and durability.
Hunter adds that you still need to use 100 percent polyester fabrics for dye-sub applications. “Different types of ink work best with different types of fabrics and the unique chemistry of dye-sub inks requires transfer to 100 percent polyester materials for optimum results.”
Paul Leh, VP, Rainbow Pigment Co., Ltd., comments that digital dye-sub inks are not suited for outdoor advertisements, due to poor light resistance that may cause the color to fade.
“Sublimation is not ideal for outdoor use due to the outgassing, dye migration, and UV fade,” agrees David Gross, president, Condé Systems, Inc. “In the coming years, I think significant progress will be made to provide a solid three-plus year product. This will be done by improving the sublimation inks and coating used on substrates. Polyester fabric will also benefit from these changes,” he says.
Juan Kim, CEO, Valloy Incorporation, believes that digital dye-sub technology is mature enough for both direct and indirect applications. “So, there will be minor variations like fluorescent and spot colors or low temperature sublimation. However, low temperature sublimation requires shorter chains of polymer, which makes washing/UV durability poorer so it is only applicable for direct sublimation of short-term soft signage.”
New Ink, New Applications
As digital dye-sub inks continue to advance and color gamut expands, applications benefit from the vibrant output produced. New fabric introductions further expand dye-sub’s appeal.
Aug2016, Digital Output