Intense Inkjet Effects

Printing, whether offset, flexo, or digital, involves the placement of ink (or toner) on a substrate, such as paper, film, or other receptive media. Inkjet prints are no different: media and ink are the two keys needed to drive the vibrancy vehicle. White, clear, neon, metallic, and even thermoluminescent specialty inks can make the end product even more vibrant to the consumer eye.

“It comes down to the creative [execution] and the printing technique used, but specialty inks are a great way to ‘marry’ substrate and ink,” explained Sean Roberts, global manager of Customer Experience Centers for EFI, which has ink-development teams and an inkjet solutions factory for its VUTEk large-format printer line. Specialty inks are, well, special, “unconventional,” added Roberts. “It’s not the same old print campaign [with them].”

Epson believes in the power of specialty inks, too. “We have some 60 chemists on staff in Japan who are continuously making improvements,” noted Reed Hecht, product manager for professional imaging. The reason any print service provider (PSP) buys a new printer is because of print head and ink technology advancements, Hecht asserted.

Industry suppliers such as EFI, Epson, and INX International admitted that specialty inkjet inks are by no means required to produce high-quality, eye-catching graphics. “The standard eco-solvent or water-based ink gamut is available in standard wide-format printers, and that is beyond most SWOP gamuts,” said Karla Witte, president of business development at INX Digital. “But the digital gamut provides intense colors. The main difference is the pigment being used, and it has different adhesion requirements for a specialty use like an advertising campaign, compared to a traditional job such as banners and signs.” EFI’s Roberts concurred, noting that the physical characteristics of specialty inks, including viscosity, are indeed different. “CMYK inks are semi-transparent, but the white ink is very opaque,” he pointed out.

The perception out there among many print observers is that specialty inkjet inks are expensive, they slow down production, and they are not user-friendly from a maintenance standpoint. Yet the reality is that specialty inkjet inks can be used effectively, efficiently, and productively. “They can be most effectively used as a spot color, and in most cases you can do it the same way with an inkjet ink as you would with traditional inks,” Witte continued. “For example, white on clear film is very important for impact color and as eye-catching spot color.”

Specialty inks represent something new for customers -- a way to help them differentiate their products, Hecht of Epson added. “These inks enable unique applications, such as window clings and window graphics with vibrant colors on clear materials.” They also are something for which print firms can charge a premium. It’s no secret that specialty inks cost more than standard inks, which average around 25 cents per ml. By contrast, white ink can command up to 38 cents per ml., while metallic silver can fetch more than 70 cents per ml.

The extra cost is a large reason why most manufacturers make specialty inks an option on presses. White ink is optional on both the Epson S-50 and S-70 models, for example; EFI/VUTEk also has channels dedicated for white ink.

Maintenance and Speed Myths

MPR inquired as to any “quirks” that make these inks easier or more difficult to use. Maintenance can be specialty ink “pain point,” acknowledged Epson’s Hecht, “which is why we build it into our printers.” An ongoing recirculation system running through the print head eliminates the need for manual nozzle cleaning, he explained. “By automating maintenance, our customers don’t have to think about it,” Hecht added.

“Almost all of these specialty inks are different, so they require a special approach,” Witte of INX answered. “White and silver inks require shaking the cartridge daily and more extensive cleaning to keep proper print-head health. Often the end-users need to clean the print head more often even when the print head is not in use.” At EFI, Roberts agreed, adding that inkjet manufacturers “tune” their print heads for specialty inks.

While these special inks do not impact production and running speeds, per se, the planning process can take much longer, Witte continued. “Typically, specialty color inks such as white and silver will slow down production. The steps needed to use these inks effectively are more intricate, so you need to allow more time,” she said. “The tradeoff is you can create truly unique printing; and because it is a niche market, you can charge more for it.”

While it is true that white and metallic specialty inks can be treated more like spot colors than process colors, prepress files are handled differently at the raster-imaging-processing (RIP) level, added Roberts. The spot color naming convention is unique within our Fiery XF RIP,” he said.

“The colors also can be difficult to control,” Roberts added, citing an EFI “pink pastel” hue that requires a blend of 30 percent white with 70 percent magenta on the same layer of the VUTEk printer’s multi-layer capabilities. The technology enables the printing of up to three layers in a single pass through the wide-format device. Many customers use a “bump” layer base image with a white layer in between, “to make the image ‘pop,’” Roberts explained. “This technique works particularly well for backlit enhanced projects on glass and acrylic,” he said, adding that the 5.0 version Fiery XF helps to keep white droplets in register better than ever before. “Out-of-register white can be very noticeable because of its opaqueness,” Roberts noted. In addition, the white layer “can be choked or spread with any nozzle deflection,” he reported. “This used to be done manually.”

In terms of turnaround times, speeds vary, of course, depending on the resolution of what is being printed: a roadside billboard at 1,800 square feet per hour or a backlit sign seen from two or three feet away. Roberts explained that production can take up to three times longer when multiple layers are employed in an EFI graphic. So, are specialty inks worth it? “You can charge five times the price,” he added with a smile.

Metallic and Glow in the Dark

Metallic specialty inks bring inkjet print to the next level, said Epson’s Hecht. “Metallics allow for unique forms of signage, including sparkling waterfall effects,” he added. “It also can be used in proofing applications and for shelf differentiation in short-run packaging.” But metallic inks also can be tricky to work with. “RIPs are key,” said Hecht, noting that Epson’s S series presses have a partnership with ONYX for out-of-the-box raster image processing. Epson also supports major RIPs from Caldera, GMG, and other software vendors, he added.

The manufacturer also has partnered with Color Concepts to create the Epson Media Qualification Program (EMQP) for the GS-6000 and SureColor series. The program provides media manufacturers with profiling and benchmarking services as well as web-based, downloadable profile distribution. EMQP ensures that media profiles provide faultless color and impeccable print quality so customers have the confidence that their output always will look brilliant. Color Concepts has similar media certification programs with HP and Mimaki as well.

UV fluorescent neon inks now allow a way for customers to customize glow-in-the-dark graphics to sell ads, recognize sponsors, localize for regional promotions or communicate about local events and promos. “Night graphics are popular for night clubs, casinos, laser tag facilities, amusement parks, private parties, and cosmic bowling alleys,” said Jeff Olson, national sales manager for Seiko Instruments USA, which features neon inks. Its Color Painter W printers offer inks in neon yellow and neon pink. “There are no tricks to running the inks on the printer,” he noted, “and speed is the same.”

Neon inks require a black light to be installed to light up the graphic, and they are not recommended for outdoor applications because they fade very quickly in sunlight. “But outdoor night events is a growing market niche,” Olson continued. “This offering is a way to provide unique, more profitable graphics to existing customers and an opportunity to expand in new markets.” He cited three advantages of neon inks:

  1. “When used with a traditional set of CMYK inks, you can produce a wide range of graphics with traditional CMYK colors, neon spot colors or a combination of process and neon colors using opacity settings in creation software programs,” Olson said.
  2. Neon inks also increase the gamut for all indoor graphics, “allowing you to hit certain colors that standard CMYK ink sets cannot hit,” according to Olson.
  3. Neon also allows for short-run signage, so it can be customized, he said.