By Digital Output Staff
CMYK ink sets are limiting when it comes to achieving brand-specific colors. To combat this, traditional analog printing uses “spot colors that are color matched by mixing individual color base components that are delivered to one station of the production press for printing. These spot colors usually must be changed between jobs,” explains Phil Jackman, global product manager, digital, Sun Chemical.
However, this isn’t a practical or efficient method for a wide format digital printer. Achieving certain colors involves applying thick layers of only CMYK. “Brand owners and end users would not be able to tolerate the reduced flexibility and blocking issues that can be associated with thick ink layers resulting from some composite CMYK color combinations,” continues Jackman.
In response to this challenge, many ink vendors offer a widened color gamut for their leading wide format ink sets, adding colors like red, orange, green, and violet. While these additions are advantageous in many application-specific scenarios, packaging is one in particular that benefits. Whether corrugated or flexible, a packaged piece must meet company’s brand colors. With an expanded color gamut, a larger range of colors makes achieving these colors much easier for the print service provider (PSP).
Above: Roland introduced new ECO-UV 5 orange and red ink options for the next-generation VersaUV LEC2-330 and LEC2-640 UV printer/cutters.
Helpful Expanded Gamut
Digitally printed packaging applications benefit from additional colors. Extended color gamut presents print providers with a larger range of colors, allowing them to meet their customer’s color needs much more reliably.
“Having a wide color gamut on a printer is very important. It allows you to hit or print more colors; colors that were previously out of the spectrum of that particular printer,” says Jay Roberts, product manager – UV printers, Roland DGA Corporation.
Specifically, Ken Parsley, production manager, Mutoh America, Inc., cites the addition of orange and green can increase the number of colors in an ICC profile by 20 percent over standard CMYK inks. “That means there are more Pantones that are within gamut. This allows PSPs to match corporate logo colors with less effort.”
“The addition of a combination of orange, green, and/or violet can extend the color gamut, increasing the number of different colors that can be achieved on the press and the ability to match the desired brand colors. This is especially important for any package printing,” agrees Jackman.
There are other benefits as well. Where digital print is favored for shorter runs and package prototyping, the final run is often completed on a different type of technology with different ink sets. It’s important the colors shown in the prototype match the final output.
Jason DeLuca, application specialist, swissQprint America, explains “for cross platform runs, where printing methods are combined—such as digital and offset for example—there will be a closer gamut, which results in less variability in color between print processes.”
In addition,“a wider gamut allows for richer, more vibrant prints while still maintaining neutral grays, smooth gradations, and natural skin tones,” says Roberts.
CMYK has always been the de facto standard for printing, and of course there are ways to combine colors to achieve the desired effect. That being said, the demand for expanded color gamut, specifically in package printing, is increasing—as illustrated by recent announcements.
Parsley believes “the desire to expand color gamut has been around since CMYK printing systems were developed. The human eye can see and differentiate many more colors than any CMYK printing systems can deliver. Corporate logos are typically chosen from a color matching system such as Pantone offers. Since some of these colors are not within gamut of a standard CMYK printing system the packaging industry must sometimes look beyond those systems to find the extra gamut necessary to serve their customer’s needs.”
More recently, Jackman says macro-influences like the COVID-19 pandemic have played a role in increasing demand for expanded color gamut. “The pandemic has caused a large shift in the product mix of many PSPs, moving away from large signage printing for trade shows, concerts, and sports events, towards facilitating online shopping via the decoration of shipping boxes or carton packaging for the myriad of small, start-up businesses that were quick to react.”
“There are many compelling reasons to consider the printing of packaging on wide format inkjet printers, ranging from prototypes and short runs to filling in any inventory gaps and shortfalls from the mainstream printers. Being challenged to match or simulate the colors of the brands is important, so the desire for orange, green, and violet inks in the process is increasing. Modern digital printers can achieve excellent image quality so even high-end consumer packaging, such as boxes for consumer electronics, can be printed on a wide format press,” continues Jackman.
These PSPs want efficiency in meeting color requests as well as accuracy. “Ultimately, the user’s desire for color consistency and accuracy are the driving forces behind manufacturers offering additional color options. That need is generated by print buyer demand for better color matching between print platforms,” says Roberts.
Red, orange, green, and violet are popular expanded color gamut options.
According to Jackman, orange, green, and violet have the largest impact on increasing color gamut because they fill the gaps between CMY. All of the ink sets within Sun Chemical’s Crystal product range for wide format graphics offer extended color gamut.
“Many different colors are investigated but the ink must show a significant expansion of the gamut to be considered as an additional color in a printing system. I think orange and green are added to many printing systems because their effect on the gamut is immediately noticeable,” comments Parsley. Mutoh currently offers orange and green with its TP11 direct to textile inks, but plans to add these colors to other ink sets later in 2021.
The decision to add new colors depends on the manufacturer. For example, Roland added orange and red UV inks to its family of specially formulated, GREENGUARD Gold-certified ECO-UV 5 inks available for the company’s advanced VersaUV LEC2 series roll-to-roll UV printer/cutters.
swissQprint offers orange in combination with CMYK—considerably extending the color gamut in orange and red. It also prints as a spot color. Other spot colors are available on request. Orange is available in its hybrid flexible KX1 UV ink.
Developing the Ink
Ink development is a long process, something that isn’t taken lightly. Sometimes supply and demand chains influence time to market as well as a host of other factors.
With supply issues the current norm, ink manufacturers are challenged in regards to offering expanded ink sets to customers. “The additional pigment colors used in expanded gamut printing are not necessarily more difficult to obtain. But as their demand is generally much less than CMYK, they tend to have longer lead times, especially when consumption increases above normal levels. Once usage levels are normalized, there would not be any supply issues,” explains Jackman.
Supply issues aside, a great deal of research and development (R&D) goes into creating these ink sets. “The color chemistry must match the current ink, and the ink viscosity has to be balanced to ensure that the ink droplets will complement the CMYK ink droplets,” shares Roberts.
The new ink also has to work with the rest of the print process. “In printer ink manufacturing, there is a trifecta that has to be met. That trifecta is comprised of the three key elements involved in all UV digital printing—the inks, printheads, and UV lamps,” continues Roberts.
Extension of Color
If clients are brand color focused, adding an extended color gamut to an existing, compatible ink set is an option. Specifically, if creating packaging applications—either flexible or corrugated—a print provider always strives to make sure a package piece looks exactly as the customer intended. Extending ink sets with red, violet, orange, or green help to achieve this in a more efficient and effective manner.
Oct2021, Digital Output