By Melissa Donovan
It is challenging to study wide format as a whole when referencing ink usage. Annually, we report on the state of the ink and this year we divide our study by traditional signage and textiles. These are two distinct application sets—one a dominant presence and another an up-and-coming player. Each has a most-used ink type due to specific micro and macro trends driving advancements in adhesion, color gamut, and durability.
Above: Polymeric offers prestige as a UV-curable ink set.
Common ink types used in traditional signage printing are aqueous, latex, solvent, eco-solvent, and UV. Traditional signage for the purposes of this article includes applications like banners, posters, hanging signs, and vehicle wraps. Print service providers (PSPs) offering these services are positioned to grow—if they want to—by transitioning into more untraditional types of projects like direct to object printing. This is possible due to the availability of ink sets.
Since traditional signage is a broad application range, ink vendors consider multiple ink sets as “most used.”
“Solvent still reigns king in this segment as the low cost and familiarity of this technology make it the preferred choice for many,” admits Volance Carlin, product manager, Mimaki USA, Inc.
A subset of this is eco-solvent, which continues to be popular for traditional signage applications thanks to versatility and outdoor durability, according to Daniel Valade, product manager, color products and cutters, Roland DGA Corporation.
New technologies enable new applications, and Matt McCausland, product manager, production imaging, Epson America, Inc., believes that traditional signage is becoming harder to define. “The majority of these applications are done with eco-solvent and UV ink,” he adds.
At Marabu North America, traditional signage is considered vinyl or banner material. “The most predominately used ink for these formats is solvent or latex technologies. This doesn’t mean vinyl or banner material can’t be printed using a UV ink though, which many people do,” suggests Chuck McGettrick, North American sales manager, Marabu.
UV ink is gaining ground when it comes to traditional signage. Reasons include cost, sustainability considerations, and substrate versatility. “The advances of UV inks have been considerable. They are more stable and easier to print with than they were in the past,” offers Nick Buettner, color and technical sales manager, Advanced Color Solutions.
Rich Gigl, SVP, National / AZON, says his company’s UV ink sales volume doubled over the last few years. The primary reason for the change is the lower cost per square foot of UV ink.
“The printing industry has seen the impressive evolution of UV in the last few years in regards to outdoor durability and lightfastness, as well increased flexibility and the ability to adhere to a greater variety of substrates. In addition, UV offers an environmentally friendly alternative to solvents, as well as cost savings when considering production time. The increased demand for personalization from customers is also a driving factor in the growth of UV-curable inks,” shares Angela Argit, marketing manager, Polymeric Group.
Stephen Emery, VP, ink business, EFI, admits UV-curable ink is a popular choice for signage and display graphics, with a number of advantages—citing flexibility as a big reason—and UV LED capitalizes on this further. “LED inkjet is even more versatile as it can be used with an even wider range of media, including heat sensitive and specialty materials,” he continues.
“Most of the inkjet inks we sell today for signage applications cover a wide spectrum of conventional UV-curing technology. However, we are seeing significant growth in UV LED with many major players in the market looking at UV LED because of its environmental and application benefits,” agrees Phil Jackman, global product manager, digital, Sun Chemical.
In addition to UV-curable and UV LED, Jeff Edwards, senior business development manager, Canon Solutions America, sees a continued shift from solvent and eco-solvent technologies to aqueous/latex. “This trend is driven in part by an applied perception that latex inks are more ecologically friendly than eco-solvents and by the real need for more productive printing systems; something UV-curable inks also deliver due to their instant cure.”
A combination of ink types is also found. “We see a mix of UV, solvent, and latex—each of which has unique characteristics for color fidelity and outdoor longevity. Because of variations in that longevity—based on not just the ink but also the substrate—the best combination for the job varies among application types,” explains Dan Johansen, senior marketing manager, wide format solutions, commercial and industrial printing business group, Ricoh USA, Inc.
Trends affecting ink usage in traditional signage include environmental concerns and quick turnarounds.
“There is a trend to move away from volatile organic compounds (VOCs) in solvent inks to low VOC water-based inks and non-VOC 100 percent solid UV-curable ink,” admits Nitin Goswamy, president, A.T. Inks.
Eric Beyeler, global marketing manager – digital printing, DuPont, agrees, saying customers are driven by improved fastness performance and lowest environmental footprint, with latex favored to address the latter trend.
Faster turnarounds and peak capacity requirements influence the adoption of new ink sets. “We are becoming a society that wants instant results and instant deliveries and product ratings of no less than four or five stars,” explains Grant French, business development manager, Digital Ink Sciences, LLC.
Johansen sees signmakers moving to UV and latex inks based on the strength of their ability to undergo finishing immediately after printing, thus meeting those quicker turnarounds.
UV-curing is quick because no heat is used in fixation. So not only is the process faster, it also extends material options to heat-sensitive substrates and “allows for the building of layers to create textures and raised, palpable prints, providing users with full control,” suggests Carlin.
“Inkjet printers continue to get faster and more versatile with the availability of value-added options that maximize the printer’s productivity and expand the range of applications that are possible—all of which are driving the macro analog to digital conversion trend and increasing ink usage,” adds Emery.
The manner in which products come to market also shape ink usage trends. “There are a decreasing number of huge campaigns and an increasing number of smaller campaigns. The more segmented the campaigns are, it changes the way classic signage prints. There is a demand for differentiation,” shares Pedro J. Martinez, CEO, Afford Inks.
Marketing campaigns now include smaller items like stickers and magnets, which is influential to ink usage. “As demand for these smaller promotional prints grow, customers want more from their printer and the ink it delivers. Brighter colors and small text with higher clarity are crucial,” comments McCausland.
In response to recent trends, ink vendors advance their products.
Manufacturers tinker with formulas to meet specific application needs, says Johansen. To print road signs, inks need to enhance the reflective characteristics of unique reflective substrates. For rigid substrates, the ink needs to offer high levels of adhesion, visibility, and durability.
“Ink sets are developed with a set of critical performance factors, including print quality, process reliability, and environmental footprint. Key to success is to find the optimized combination of these market needs,” explains Beyeler.
To address speed—faster turnaround and higher peak capacities—manufacturers work with phase-change ink technologies such as free radical UV-curable inks, according to Edwards. Or they develop new UV technologies, like Canon Solution America’s Océ UVgel, which is an instantly cured UV ink.
As UV ink’s popularity grows, vendors find ways to make ink more durable and flexible so it can be used in more untraditional applications, notes McGettrick.
Jackman agrees, explaining that Sun Chemical’s customers associate its UV inks with high degrees of enduring flexibility. “Print providers’ equipment is running faster, and the inks need to cure on a range of substrates. Value is often a factor for our customers, but it is balanced by application needs and the versatility of the ink’s performance on many substrates.”
Solvent inks have evolved over time to meet both regulatory and user demands for increased environmental stability. “Eco-solvent is a great example of this. It uses a mineral oil rather than a chemical solvent. This makes the ink significantly more environmentally friendly,” admits Carlin.
Research and Development
Ink’s research and development (R&D) is driven by market demands, customer needs, application introductions, and technology changes.
“Application suitability and print productivity remain primary drivers of R&D for inks used in traditional signage. No one ink from any manufacturer can meet every market requirement,” advises Edwards. An ink that does it all remains the “holy grail” for ink manufacturers and PSPs and doesn’t yet exist. This is what drives a good ink development organization, he continues.
Users of the technology in particular have wants and needs that influence ink production. “From our perspective, it is strictly customer demand. We are getting asked to support inks that are semi-transparent, flexible, offer wider color gamut, white whites, and denser blacks,” shares Gigl.
“Customers always look to improved print performance, lower total cost of manufacturing, repeatability, and low environmental footprint,” says Beyeler.
At Roland, print provider demands constantly drive the development of ink formulations that not only deliver vibrant, detailed prints, but also offer maximum versatility across multiple substrates.
Depending on the usage requirements, some print providers look for solutions that provide durability but also require minimal ventilation. “Pigment ink provides weather resistance for short-term outside signage. Markets like retail, schools, construction, real estate, and small offices can take advantage of this,” shares Edward LaManna, senior manager, product marketing, Canon U.S.A., Inc.
Many ink manufacturers offer mass market ink sets, but also provide the option for customized solutions. “As an ink manufacturer we have the ability to maneuver swiftly when customers or market segments require a custom solution that is far from traditional,” explains McGettrick.
Look into the Future
The future of ink for traditional signage continues to move toward more environmentally friendly compositions.
Gigl believes there will be more environmental and chemical restrictions.
Martinez agrees, expecting to see major changes in inks due to environmental regulations. He points to REACH regulations and Proposal 65 as already dictating which raw materials can and cannot be used in ink sets. Also, raw material supply problems along the supply chain have and continue to effect ink supplies.
“The trend should be taken seriously as various jurisdictions begin to pay more attention to the colorants used in graphics, particularly as they relate to occupational safety, print use, and recyclability of printed matter,” suggests Edwards.
Volume of ink used per square foot is also a factor. “Ink technologies that require two, three, or even four times the ink volume to create an image will become more difficult to justify—especially since many of these evaporative technologies have VOC components exceeding 25 percent of volume,” he adds.
Common ink types used in digital textile printing include acid, aqueous, disperse, dye, pigment, reactive, and sublimation. Textile-based applications for the purpose of this article include soft signage, apparel, and décor.
At this time, sublimation-based ink and the printing process as a whole is popular for a number of reasons. “Dye-sublimation (dye-sub) is the easiest to implement and as a result has grown into a large segment. The main advantage is there is no requirement of pre- and post-treatment of the fabric. However, the technology is limited to only polyester substrates and its blends,” explains Goswamy.
The popularity of the sublimation process can be seen in both the cost reduction of the final product as well as the decreased expense related to ink and paper, continues Marty Silveira, VP sales, DigiFab Systems, Inc. “Interest is also illustrated by the number of printers sold and the growth in higher speed printers coming to market.”
Jackman points out the inventory and stock redundancy advantages with dye-sub transfer ink in particular, especially compared to directly printing on the garment. “The financial risk of holding stock of printed transfer paper is lower than holding stock of finished garments, and the disposal cost of unwanted or unsold transfer paper stock is significantly lower,” he adds.
Pigment and reactive ink sets are becoming more popular, primarily because more users want a greater variety of textiles to print onto and these types of inks allow for this.
“One major demand from customers is to provide pigmented ink that can achieve the best of all inks and are substrate independent. However, significant R&D is yet to be done in this area to solve some of the challenges in reliability and print quality,” admits Goswamy.
Beyeler points out that it is important to note that reactive inks are attractive because they are some of the lowest priced solutions for printing to cotton.
There is a drastic increase in textile-based applications in general.
“Soft is taking the place of rigid and heavy substrates for trade shows, high-end retail, and backlit applications,” shares McGettrick.
Other applications driving ink usage include fast fashion and activewear popularity, adds Beyeler.
Environmental considerations also play a role. “Some traditional textile inks, such as reactive dyes, create a lot of waste water in their pre- and post-production processes. This is becoming a serious environmental issue that major garment brands want to address. As a result, many large print suppliers invest in pigmented inkjet textile inks as a waterless print finishing solution to reduce pollution,” says Jackman.
To meet demands, ink sets adapt in regards to hardware, color vibrancy, or substrate compatibility.
With an increase in single-pass textile machines, reliable ink sets are in high demand. “The presence of a large number of printheads in a single machine, coupled with low drop volumes make for stringent demand on ink. These are slowly met with help from innovative ink chemists and machine and printhead designers,” shares Goswamy.
Color vibrancy must meet or exceed customer expectations. This was once difficult to do with pigment ink in particular. “It suffered flat or dull colors. New ink chemistry has resolved that and although digital pigment will never challenge reactive color quality, with a solid pre-treatment regiment and new formulation pigment inks, the results are now inline with user expectations and produce vibrant results,” explains Carlin.
“Not only are inks required to adapt to the changes in printhead and printing equipment but also the substrate coatings need to keep pace,” says Silveira. DigiFab now offers seven ink-specific fabric coatings for use with all ink types. “These ink and fabric combinations allow users to get the best results from their equipment while maintaining consistency and cost,” he adds.
Marketplace demand and technology changes drive development in ink sets for textile printing.
Beyeler believes that companies manufacturing and optimizing ink components such as dispersions, dispersants, and polymers are best positioned to create formulations that meet the increasing print standards of the digital textile market.
Cost is a major R&D driver, according to Carlin, citing sublimation ink prices in particular as being under pressure. “Original ink manufacturers constantly research new pigments and chemistries to keep ink costs competitive.”
More color and better fastnesses—wash, color, and rub—drive development, according to Martinez.
The search for the “one ink to rule the world” also fuels research labs. “There is a demand for one-size-fits-all ink. For example, dye-sub inks are used for polyester, while pigment inks are used for cotton. It would be ideal to have an ink type that could be used for both. Not only that, the ultimate ink would also offer all the best durability features,” admits Lily Hunter, product manager, textiles and consumable supplies, Roland.
Look into the Future
Fabric printing in comparison to other segments of the industry is not as mature. There are constant changes.
As a whole, “as digital textile printing becomes more mainstream, costs and speeds will only get more attractive and we’ll see the industry rapidly move from traditional analog to digital printing,” shares Goswamy.
“We are starting to see more direct to textile and imaging to natural fabrics. Printing to natural fabrics is the future and people are going to want to get away from transferring,” adds McGettrick.
Martinez believes that ideally pigmented textile inks will replace reactive and sublimation. “As they would be able to give the right adhesion and resistance on multiple substrates, but we are still far from that,” he cautions.
Speed, cost, and environmental concerns remain some of the top driving factors in ink development, whether it be for traditional signage or textiles. Ink chemists work in tandem with hardware and printhead manufacturers to achieve ink sets that meet and perhaps exceed these goals.
Apr2019, Digital Output