UV-cure inkjet printing technology has steadily improved and developed since it was introduced more than a decade ago. With new developments in equipment technology, inks and media, UV-cure technology has matured and enjoyed rapid adoption in a number of markets over the past few years. 

 

In the wide-format inkjet space, it has quickly evolved from mainly a flatbed inkjet printing technology to one that has become very versatile for a host of applications. Many believe that UV-cure technology offers graphics output providers the best mix of safety, reliability and material compatibility that the industry has seen in quite some time. 

 

Mimaki’s UV LED line-up includes the JFX Series Flatbeds (JFX-1631 Plus shown) as well as the UJF-3042 tabletop model and Hybrid UJF-160 64” wide roll/rigid model. (Image courtesy of Mimaki.)

As the industry continues to adopt UV-cure technology, an increasing number of print service providers are looking at high-speed UV-curing flatbeds and hybrids, as well as dedicated UV-curing roll-to-roll printers.

 

Better ink formulations, new LED-based UV-cure lamps and new printhead technologies have come together to create a market that has made the segment much more cost-competitive with solvent inkjet printers. Today, most of the major wide-format equipment makers have some stake in the UV-cure inkjet market. And several printer manufacturers—including Mimaki, Roland and EFI—have become pioneering leaders within the newer LED-based UV-cure inkjet printer segment. 

 

LED UV-Cure Technology Emerges

“The rapid adoption of UV LED curing technology is due to the inherent advantages of economics, new system capabilities, and environmental improvements,” says Chad Taggard, director of marketing and business development at Phoseon Technology, a UV cure-lamp manufacturer based in Hilllsboro Ore. “UV LED technology now has the performance to replace mercury vapor and metal-halide arc lamps used in virtually all UV-cure printing, adhesive and coating applications.”

 

Roland’s VersaUV LEF 12” Benchtop UV flatbed printer uses an LED-based UV-curing system and can print directly onto three-dimensional objects. (Image courtesy of Roland DGA Corp.)

In fact, Taggard says, the adoption of LED-based UV-cure technology has become a major trend in the world of UV-cure inkjet printing, adding that the new technology allows printer manufacturers to offer lower operating costs, higher quality output and expanded printing capabilities. UV LED cure lamps, he says, have longer lifetimes, run cooler, contain no mercury, are less expensive to operate and generate no ozone, as do many conventional arc lamps. And Taggard is not the only one excited about LED-based printing technology.

 

“We are seeing more wide-format printer manufacturers considering and offering UV LED curing technology in newer devices,” says Paul McGovern, national sales manager at Mimaki USA, Suwanee, Ga. That’s because, “in addition to lower operating energy costs and faster start up times, LED cure lamps can last up to five years, and allow printing onto heat-sensitive substrates. This is a major influence in cost of ownership comparisons and is helping to move this segment to the forefront. 

 

The iPad case and set of headphones shown were direct-printed using Roland’s VersaUV LEF 12” Benchtop printer. (Images courtesy of Roland DGA Corp.)

“Still, conventional arc lamp technology continues to be a factor for the speed of curing in higher-speed printers equipped with multiple printhead arrangements. And conventional inkjet UV-cure lamp enclosures are now more compact and lighter, and are equipped with more efficient air and liquid cooling systems.”

 

Hiroshi Ono, group product manager, Roland DGA, Irvine, Calif., also agrees that recent developments in LED-based UV-cure lamp technology have been a real game-changer in that product category. 

 

“LED-based UV-cure technology is revolutionizing the production process and is opening up new markets,” Ono says. “There is such a wide range of applications for UV-LED technology, the opportunities are endless. This is especially true when the technology is paired with other advanced features, such as integrated contour cutting capabilities and specialty inks.”

 

The FireFly air-cooled LED-UV lamphead from Phoseon Technology. (Image courtesy of Phoseon Technology)

Pros and Cons

There are pros and cons for both approaches to cure lamps in today’s UV-curing printers. Experts say that conventional metal-halide and mercury vapor arc-type UV-cure lamps, though very effective, are expensive to replace, lose curing efficiency over time, and, when in use, release ozone into the work environment. Another downside to conventional UV-cure lamps is the intense heat generated that can warp or damage heat-sensitive substrates. 

 

“Some inkjet manufacturers, in response to concerns about escalating costs and environmental issues, have gone to LED,” says Larry D’Amico, VP of digital imaging for Agfa Graphics North America, Ridgefield Park, N.J. “The major advantage would be that the cooler operating temperature provides greater media flexibility. However, if speed needs to be sacrificed in order to accomplish some of these goals, then it is not yet a legitimate alternative. As such, LED seems to be more popular on slower, lower-end devices.” 

 

But Roland’s Ono states that newer LED-based UV-cure lamps are redefining the UV world. “UV LED lamps last up to 10,000 hours—10 times longer than conventional UV lamps—for dramatically lower operation and maintenance costs. They also emit very little heat, which makes them much more versatile with respect to the media they support. And while UV LED printers may take longer to print than conventional UV-curing printer systems, they require no warm-up time, so they are ready to start printing immediately after being powered on. They are also more energy efficient, and are completely ozone-free, making them a safer alternative to conventional UV-cure lamps. For these reasons, LED UV technology presents a much better overall value to the print service provider.” 

 

These output samples from PVS In-Store Graphics were printed using the EFI VUTEk GS3250LX to print onto wood and metal. (Images courtesy of EFI and PVS In-Store Graphics)

Ink Trends

On the ink side of things, leading ink manufacturers see the great potential for the growth of LED-based UV-cure printing. 

 

“We have seen huge advancements in UV-cure technology in the last 10 years,” says Ken Kisner, President of INX Digital International, San Leandro, Calif. “At INX Digital, we’ve developed inkjet inks that work well on a wide variety of substrates. We have also produced very focused formulations that perform specifically well for certain substrates like glass, tile, plastic and corrugated packaging and others.”

 

Kisner points out that his company has developed four specific base formulas of UV-curable ink: Stretch INX for wrap applications, Rigid INX for rigid substrates, Multi-Flex INX for hybrid applications and Flex INX for roll-to-roll materials. 

 

“Each of these categories can be aligned to the specific needs of a market and can be optimized for a set of substrates,” he says. Kisner says as markets for specialized inkjet inks continue to grow, they are seeing more dedicated machines for single purposes. 

 

PVS output the thermoformed sign shown here on their EFI VUTEk GS3250LX. (Image courtesy of EFI and PVS In-Store Graphics)

“Advancements in LED curing technology allow these systems to have lower energy use and constant light output,” Kisner says. “Also important is the significant introduction of low-viscosity monomers that give ink chemists more latitude in their formulations. INX Digital is now able to develop inkjet inks with extremely high pigment density and to integrate other types of polymers to get unique attributes. Many of these new attributes lend themselves to fixed-array, high-speed printing.” 

 

McGovern is excited about new inks being developed for LED curing. 

 

“Today they are making LED cure UV inks that are chemically ‘matched’ to the waveform properties of the LED lamps that manufacturers are currently offering for inkjet printing,” he says. “These new inks allow much faster cure rates; and that enables much faster operating speeds and increased production without the need of post-curing methods (a second dose of UV light).”

 

EFI’s Faster LED Printer Speeds 

“Earlier this year, we introduced the EFI VUTEk GS3250LX,” says Ken Hanulec, VP of Marketing, EFI Inkjet Solutions, Meredith, N.H. The 126"-wide LED UV-curing printer is capable of 1,000 dpi and eight-color (plus white) speeds of up to 1,200 square feet an hour. “It’s a fully loaded, production-level hybrid printer that extends the range of supported substrates and features an innovative ink curing technology. 

 

Agfa recently expanded the color gamut in its :Jeti 3020 Titan UV-curing printer to include orange and violet, giving it the ability to hit more spot colors. (Image courtesy of Agfa Graphics)

Hanulec points out that PVS In-Store Graphics, located in Portland, Ore., installed the GS3250LX earlier this year. According to PVS co-owner Wes Shinn, the company has already seen the benefits of their investment. 

 

“We’ve been able to print on a much wider range of materials than ever before, opening up new opportunities we couldn’t pursue previously,” Shinn says. “Equally important has been the benefits of the new ‘Cool Cure’ technology. For example, with a much lower UV cure temperature, we have been able to use thinner styrene sheets at half the cost of what we previously were using, literally cutting our material costs in half. The key advantage is our ability to run different types of materials and thinner materials at a much lower cost without sacrificing any quality or speed.”

 

Roland Opens 3-D Opportunities

Roland’s Ono explains that UV inkjet ink traditionally has had a fairly rigid composition, which had limited the range of applications for it. 

 

EFI’s VUTEk GS3250LX printer incorporates “Cool Cure” LED-based UV-cure technology and boosts high productivity with its continuous board printing capability. (Image courtesy of EFI VUTEk.)

“Now, with more flexible inks, including Roland’s new ECO-UV S ink, UV inkjet technology not only supports a wide range of materials, but can effectively wrap a product’s contours, corners and indentations,” Ono says. “ECO-UV S stretches up to 220 percent, allowing it to conform to even the most complex surfaces. This new advancement is opening up several markets, including the design and production of packaging prototypes of virtually any organic shape. New ink formulations can even be used to print on vacuum forming materials commonly used in the production of control panels, automotive parts including dashboard components, and casing for electronic devices such as cell phones and MP3 players.” 

 

Ono says that Roland’s wide-format VersaUV inkjet devices support both flexible and rigid substrates, from PVC, leather, paper and board stocks to foils, plastics and films. 

 

“This makes them well suited for applications ranging from signage, P.O.P. and interior décor items to packaging prototypes, labels and specialty graphics,” he says. “We just introduced a new flatbed VersaUV printer, the LEF-12, which prints directly onto three-dimensional objects, ranging from key chains, giftware and awards to smart phone covers and even laptop computers.”

 

The speed and quality of UV-curing devices such as Agfa’s :M-Press Tiger are starting to impact applications traditionally held by offset and screen print technologies. (Image courtesy of Agfa Graphics)

Agfa Expanding UC-Cure Options

Agfa doesn’t have a UV LED printer at this time, but is a major player in the UV-cure printer space with its :Anapurna line of UV-curing printers, and other printer products such as the :Jeti 3020 Titan unit. 

 

“Print service providers are looking for systems that can help them image corporate colors more efficiently,” D’Amico says. “For example, we recently expanded the color gamut in the :Jeti 3020 Titan to include orange and violet, giving it the ability to hit more spot colors.”  

He says that increases in quality and speed in UV-curing devices are starting to impact offset applications. 

 

“The Agfa :M-Press Tiger, for example, is helping to create new opportunities in this new market,” D’Amico says. “Printers are discovering they can do some things more efficiently with digital technology. Both the :M-Press Tiger and :M-Press Leopard are unique in the speed and quality they deliver with Agfa’s low ink lay-down. It has the look and feel of an offset sheet making it very competitive in the short run end of this market.”

 

LED Printer Options from Mimaki 

Mimaki USA was an early pioneering adopter of LED-based cure-lamp technology for the printers aimed at the signage and graphics marketplace. Some of their recent UV LED models include the JFX Plus Series Flatbeds (two bed sizes) and the UJF-3042 tabletop model as well as the Hybrid UJF-160 64-inch wide roll/rigid model. The UJF-3042FX can print white and clear, and has an automatic primer application function.

 

Looking ahead to possible future equipment trends, McGovern sees E-beam (electron beam) curing systems as a possible “next big innovation” in this area. “If E-beam curing ever becomes more portable and less expensive, it is certainly a curing technology to watch. The E-beam curing devices used by commercial printers in printing press facilities are far too large, cumbersome and expensive to integrate into wide- or grand-format printers today. However, it is a great alternative to UV curing without the photoinitiators and chemistry of free-radical UV-curable inks which offers lower cost ink and fantastic flexibility.”