Niche applications thrive thanks to print service providers (PSPs) who are experienced in their craft. The same is true for specialty substrates and ink sets. White ink is no exception. While slow to take off due to cost and speed issues, those using white ink recognize its potential. It enhances many applications and enables printing on a wide range of substrates.
Spreading the Wealth Through Applications
Clear substrates such as static cling and adhesive back film are utilized in point of purchase and signage for windows and decals are often used with white ink. “Many UV print applications are on white substrates such as Sintra or Gator. The benefit is in the ability to use clear and color substrates and still have the white when you need it for reflective and translucent viewing,” states Bill Grambsch, sales manager graphics, Polytype America.
Backlit graphics are also finding great success with the addition of white. “The purpose is to reach the same visual effect with and without light emitted through the back of the image. Most backlit applications look as they should when light is emitted through the back, but look too dark when the light is turned off. A layer of white improves this,” shares Steven Potthoff, national sales manager, :Jeti and :Anapurna, Agfa Graphics.
Also, colored substrates can be printed on with white ink. “It eliminates the need to flood coat ink on the entire background of a substrate. For example, a PSP can purchase black Sintra and print white letters. This is more efficient because it uses less ink than before, when a printer would reverse out of a flood coat of black ink on a white substrate,” explains Larry Hettinger, product marketing manager – graphic inks, graphic systems division, Fujifilm North America Corporation.
In all cases, PSPs’ options are broadened with white ink capabilities. “It introduces several new tools in their sales arsenal. First, it enables better performance and new applications on a variety of substrates. Using white ink with digital printing technology is often more efficient than in an analog process—it is a one step process versus a two step process with screenprinting,” adds Sandy Gramley, Scitex aftermarket supplies manager, Americas, Hewlett-Packard (HP).
The Challenge of White
The chemical composition of white ink is dense, so it must continually run to prevent build up. Many printer manufacturers created separate white ink lines in their devices to ensure constant movement. As end users do not necessarily print white every day, automated processes exist to prevent clogging.
Eric Zimmerman, product manager, Roland DGA Corporation, suggests that end users manually agitate ink cartridges before each use to ensure ink lines flow properly. Grambsch also notes that white ink needs to remain homogenized and not separate into liquid and pigment and settle into the ink tank.
Ink manufacturers continue to try and achieve the brightest white possible. “It is difficult to disperse white pigment down to a jettable size without it turning gray. The less opaque it is and becomes, you have to make adjustments,” cites Karla Witte, VP of product development, INX Digital International Co.
Separate from keeping it print ready, the end user must learn how to design files that work well with white ink.
“Today’s printers and RIPs are making the use of white and clear inks increasingly uncomplicated. I feel the challenge is with the designer and print shop operators and their knowledge of how to apply white ink. If you know how to use it the applications for it are almost endless,” explains Fran Gardino, business development manager, Mimaki USA, Inc.
“The design and prepress side of the workflow requires the most degree of learning. One has to start thinking of white as a spot color that is separate from the default white media color in design software. The white can be used underneath, in between, or on top of CMYK ink,” agrees Randy Paar, marketing manager, Océ North America.
Speed is also an issue, as Gramley points out. Printing, especially in underflood or overprint modes, requires a slower print speed versus standard CMYK.
White Ink Roundup
The :Anapurna Mw, :Anapurna M1600, :Anapurna M2050, :Jeti 1224 HDC FTR, and :Jeti 3020 Titan utilize white ink. These Agfa devices either come with white ink or it is offered as an option. For example, the Titan utilizes white ink optionally for commercial printers that would benefit from the niche. The :Anapurna Mw is an entry level device that automatically offers white ink, unique for printers at that level.
EFI’s QS2000, QS3200, GS2000, GS3200, QS2200, and GS5000r printers all feature white ink capabilities.
Fujifilm provides white ink in both its Uvijet and Color+ ink families. Uvijet is formulated for Inca and Acuity printers while Color+ focuses on those devices equipped with superwide piezo print on demand printheads. Both feature fast curing and are suitable for both indoor and outdoor applications.
The HP Scitex FB500 and FB700 printers offer white ink capabilities as an upgrade to interested end users. The conversion is fully automated, as customers can choose between six or four color plus white configurations and switch between as the need arises. Ink used is HP FB251 White Scitex Ink, which offers good opacity, a smooth appearance, and sufficient adhesion properties. Both printers include a white ink homogenizer, which agitates the ink in both the cartridge and printhead reservoirs preventing pigment sedimentation.
INX Digital offers white ink for printers from HP and Mimaki.
Mimaki’s JV33 series, CJV30 Series, UJV-160, JFXplus Series, UJF-706, and UJF-3042 printers utilize white ink. They are engineered to provide end users with a broader portfolio of capabilities and applications.
For Océ’s Arizona series of UV flatbed printers, two formulations of ink carry white capabilities, Océ IJC255 and IJC256. When equipped with a white ink option, they work with the Océ Arizona 360 GT, 360 XT, 550 GT, and 550 XT printers.
Polytype’s Virtu RS25 and RS35 UV printers are white ink capable. With 48 printheads, 12 are configured for white, which allow for a dense, opaque white without double striking or additional print passes. In addition, the Virtu series provides a circulation system to keep white ink moving, as well as a valve system to flush the white printheads with a cleaning solution.
Roland’s White Eco-SOL MAX ink works with the company’s SOLJET PRO III XC-540 and VersaCAMM VS series, while its White ECO-UV ink is compatible with the VersaUV printers and printer/cutters. All of the printers include a proprietary ink circulation system, which transports white ink every eight hours to prevent pigments from settling in the lines. The configuration controls the discharge of white ink and helps minimize waste by monitoring its usage. Through the Roland VersaWorks RIP, the printers output white text, graphics, and floods on coated and uncoated media providing durable and scratch resistant graphics.
swissQprint’s Impala and Oryx UV flatbeds—distributed by Polytype—offer a white ink option. With nine and eight channels, respectively, each allows one channel to be configured with white. Both feature print drivers and control software that adjusts the amount of white ink applied to a graphic, resulting in a translucent or opaque effect. Additionally, the print control software can be used to output a white flood coat without having a RIP supply white data, which allows for white printing with any color file. To maintain homogenization, the Impala and Oryx provide a separate vacuum system to ensure the white ink jets properly. Also, an air valve system operates while the printer is at rest to keep the white ink constantly moving to prevent drying or separation. White ink is constantly circulating in these printers. If there is no white ink activity for three days, the software reminds the user to flush the printheads with a cleaning solution.
A Bright, White Future
A recent addition to the ever expanding digital ink specialty market, white continues to mature. Witte says a brighter white ink is always the goal and manufacturers continue to strive to offer this to their customer base. Some vendors are looking into using polymers to create the white component, as opposed to the traditional Titanium element. The ink itself looks clear, but when it dries, it becomes white.
Stability also continues to advance. “We continue to find ways to improve the stability of white as the pigment is inherently not as stable as other color pigment dispersions,” shares Stephen Emery, senior director, EFI Ink Business. These advancements slowly move white ink out of the niche market and into common place. As speeds increase, more PSPs are willing to add white ink to projects, because it will be a value-add, not a cost prohibitor. In the second part of this series read about end users finding success with white ink.