Inkjet Capability

Inkjet has stamped its place in commercial printing, but will it ever mean more than coding and marking in package printing?

by Kate Sharon

"DIGITAL" IS THE buzzword in package printing today. There's digital printing, and even some diecutting, anilox engraving, and platemaking processes have been digitalized. But digital printing—specifically inkjet—is on the minds of many in the industry, and everyone wants to know how the new technology stands up to its conventional counterparts.

Inkjet basics

More and more inkjet products, designed for packaging applications, come to market each year. While the technology itself attracts attention, its big price tag and muted capabilities often turn converters away.

It's true that inkjet printers are more expensive than conventional presses, as are inkjet inks. Inkjet also requires printers to trade-off speed for image quality and vice versa.

However, for each negative attribute of inkjet, there's a positive. Most printers who call Curtis Miller, president of Printing Technology Services, Inc. (Clearwater, Fla.), are interested in new technology that will decrease their cost of printing, reduce hassles they've had with their current equipment, technology that's easier to use and is more flexible, and reduces their cost per run. "For the most part, inkjet will help," Miller said.

Inkjet also offers the inherent benefits of a digital workflow, including customer responsiveness, lower waste, and new market opportunities, said Luc Dupont, vice president sales and marketing at Aquaflex Inc. (St. Bruno, Quebec).

It's that kind of important information that's essential for package printers to know, which is why so many inkjet suppliers have turned into the industry's main inkjet educators. Printers need to know there's more to inkjet than ink cartridges, such as:

• Inkjet print heads are ink-specific. "People need to be educated on what's the right inkjet printer for them and what's the right inkjet ink for that printer," said Jason Oliver, sales and marketing director of Jetrion LLC's Integrated Solutions (Ann Arbor, Mich.). "They need to know what quality is possible and what inkjet ink is suitable for the substrates they use."

• There are two main kinds of inkjet printing—continuous inkjet (CIJ) and drop on demand (DOD). CIJ prints at higher speeds than DOD, but prints lower quality images, Dupont said. CIJ is also limited in the type of inks it can use, which, in turn, limits applications. It's best suited for coding and marking.

DOD prints slowly, but does so with higher resolution than CIJ. In addition, DOD can be used with a broader range of inks that are better suited for packaging needs. DOD is ideal for color graphics for packaging. (Read more on types of inkjet and inkjet inks in "Understand inkjet technology" in the January 2004 issue.)

Where it's at

Inkjet is the printing process of choice for secondary graphics, barcodes, and other variable-information printing. Thus, most of the technology available today is designed for coding and marking.

Aquaflex's Argio System prints 600 dpi—the quality required for high-precision barcode applications. Much of the demand for Argio is variable-imaging printing. "This could range from word changes such as ingredient labels, to barcodes and sequential numbering," Dupont said.

Hewlett-Packard's (Palo Alto, Calif.) thermal inkjet printer for package coding features a disposable print head that can fire 12,000 dots of ink per second from each of its 300 ink nozzles, equaling 600 x 600 dpi. HP's system is designed to apply barcodes on the line, as well as logos and dates, said Liz Philips, segment manager of HP's Specialty Printing Products.

Printing Technology Services, Inc. offers its JetFlex™, a variable-data electronic printing system. JetFlex can be integrated with continuous web presses or sheetfed packaging applications. Using HP inkjet water-based ink, JetFlex prints up to 500 fpm at resolutions up to 600 x 600 dpi in black, red, blue, green, yellow, and invisible. JetFlex's disposable print heads can be seamlessly stitched together up to 8˝ wide and larger, said Miller, and because they are disposable and changed at regular intervals, clogged print nozzles are much less of an issue. It's ideal for numbering, barcoding—including two-dimensional barcodes—and other variable-information printing like bitmaps and PDF files.

"A vast majority of what inkjet is used for in packaging right now is coding and marking," Oliver said. "But there's some fairly new equipment out there that can print full webs and full color for labels, cartons, and tags. That's a very small piece of the market now, but it should grow rapidly when inkjet becomes more reliable and receives more exposure."

One such inkjet technology that can currently go beyond coding and marking, with the aid of some conventional printing equipment, is Mark Andy's (Chesterfield, Mo.) DT2200 digital inkjet printing system. The DT2200 uses the dotrix SPICE (Single Pass Inkjet Color Engine), which is positioned on the press between standard flexograph print units. The system prints a 13˝ wide web at 80 fpm. It's piezo drop-on-demand inkjet technology prints 300 dpi resolution with eight levels of gray per spot.

In the near future, as prices fall and inkjet technology advances, more inkjet printers will be available for a wider array of applications, said David Harbourne, president of FusionUV (Gaithersburg, Md.). "The goal, clearly, is to have inkjet look as much like offset printing as possible in terms of quality. It's not there yet, but it's moving in that direction," he said.

What's next?

Inkjet's role in the future of package printing, and whether it will ever become a mainstay for printing primary graphics, is still to be determined. However, inkjet is currently filling a demand for dependable printing with a high degree of accuracy. But not every printer needs inkjet right now, said Sean Skelly, Jetrion director of product management.

"Let's say you want to go on a trip and I give you a boat as your solution, but you planned on driving—I haven't really helped you. It's like that with inkjet sometimes, because it's very much dependent upon the package printer's end-user specific requirements," Skelly said. "I need to know what the printer's detailed requirements are before I determine whether CIJ or DOD is best, or whether an off-the-shelf solution will work, or if it has to be a custom solution—or if the solution's not inkjet at all, and we have told people that.

"Printers shouldn't want inkjet just because it's a new technology," Skelly added. "It needs to be a business-based decision, not a technology-based decision."

There are a few things that printers need to determine before moving ahead with inkjet printing, Dupont said:

• Determine the kinds of applications, current and foreseeable, and the environment that the end product will be subjected to. "This will eliminate all technologies that cannot use the proper ink type needed," Dupont said.

• Consider the cost of operation of competing technologies and the way it will be integrated into the workflow. This will help make the best selection.

• Be certain that the technology is operator-friendly and easy to use to ensure an efficient production

environment.

• "Consider end use requirements—product, abrasion, and fade resistance," Dupont said. "This is a priority as the inkjet system must at least meet these requirements. If it does not, nothing else matters."

While suppliers are optimistic about the prospects of inkjet printing in the world of packaging, they don't expect digital technology to clear out today's conventional old-faithful processes.

"Traditional printing is not going away," Skelly said. "We expect inkjet to be a complementary technology to flexo and other printing technologies. We see these two technologies sitting side by side for a very long time."