On Print | Inkjet and Beyond

Published: February 14, 2012, By Dene H. Taylor

The merits of digital print technologies are debated at seminars hosted by IMI and AWA

Trade events centered on a technology stimulate thoughts about what could be done in the future but not necessarily what should be done. But that was not the case at the recent Digital Printing World 2012 Conferences in Orlando, FL, where Alexander Watson Assoc.’s Inkjet & Digital Label/Packaging Printing Seminar was co-hosted with Information Management Inst.’s Digital Printing 2020—Opportunities & Challenges Symposium, its 21st Annual Ink Jet Printing Conference, and its Ink Jet Academy.

So although inkjet was center stage, the merits of thermal, thermal transfer, and toner printing also were debated. And by including markets where traditional print is thriving, the commercial realities that printer/owners deal with daily could not be ignored.

For example, the digitization of the workflow, plate preparation, and print color control, combined with adoption of rapid changeover techniques, now have made the minimum run size much more dependent upon the machine options the owner has available, than on simple run-length economics. For well-equipped and busy shops, the decision often is determined by line availability, and the crossover quantity might be more than an order of magnitude and not merely a factor of two or three.

From an image quality perspective, the recent advances in inkjet are all about reduced dot size achieved through smaller droplets closely spaced, deposited at greater frequency, and running at faster speeds. Control of color is proving difficult because there are so many combinations of ink, substrate, and printer set up that almost every installation is unique. Efforts to standardize outside of limited common interest groups are not expected to be successful because the work crossing digital presses is so varied – in market, content, and materials.

The color specialist appears to have job security. Light colors are becoming obsolete, but the channels vacated can be used to expand the gamut so many more standard colors can be produced from a limited ink set without reverting to spot inks. Durst and other inkjet OEMs making ultraviolet (UV)-cure devices, add orange, green, and violet for this effect. Opaltone has converted flexographic, gravure, and offset presses in the traditional market for its cyan, magenta, red, green, blue, plus black color management family, again to eliminate spot colors, and now has added proofing with Epson machines with the same ink pigments, so that circle is complete.

Press speeds of 400–600 fpm on printers 30–40 in. wide are seen in the commercial and publication markets, but there they use aqueous inks and uncoated free sheet, which has limited utility in labels and packaging. However, UV inks can be printed in similar configurations on the common papers and films, including polyethylene, so they have opened the door to much more of the label industry—they give good color, very good durability, and adhere well to many of the same substrates used for flexo and gravure.

Indeed, there are integrators who install UV-cure inkjet printers on existing presses, so that current customers who have the finishing capability in place now can have short runs produced quickly to the same physical specifications and made with the same materials – no re-qualifying alternative substrates, or purchasing additional finishing equipment and tooling.

The exemplifiers of toner printing are the Xerox iGen 4s and the roll-fed machines from Xeikon and HP Indigo, not merely for their printing, but because they are being integrated with machines performing the adjacent steps in the process, such as die-cutting, scoring, over-laminating, and over-coating, as well as, in the case of Indigo, substrate pre-coating. A strong niche for toner printers is in food labeling and packaging, as the food contact regulations are met. In this same area, inkjet is limited because water-based inks need special substrates, solvent is undesirable, and the migration of UV-cure components is an ongoing concern.¹ Print speed and production costs are the limitations of toner technology.

Direct thermal’s uses for checkout, labels, tags, and tickets continues to be secured with progression down the cost experience curve—faster, more durable, and at lower cost. Similarly thermal transfer has little challenge in its segment of the durable label industry (monochrome and color), while also showing cost experience progression.

It is notable that digital printing presses are being installed in the label and packaging community more to provide complementary capability than to displace or replace conventional presses. And now it is brand managers driving the market, rather than the forward-looking print business owners, as they have learned digital allows them to do things they couldn’t do before, in terms of short runs and rapid turnarounds for specialized marketing.

These buyers are also approaching their print suppliers with opportunities in which the answers are not yet defined—where there may be a digital press with suitable capability but an ink/substrate combination is lacking. Producing special substrates may not make economic sense, but helping find solutions that can use existing substrates does.

¹Printers also must be cautious with UV-cure inks because they have total responsibility to cure 100% of the product—if they ship any of the current inks uncured they always will be uncured, whereas solvent and aqueous inks eventually dry.

Printing expert Dene Taylor, PhD, founded Specialty Papers & Films Inc. (SPF-Inc.), New Hope, PA, in 2000 for clients seeking consultation for technical management, new product design, development, commercialization, and distribution, as well as locating/managing outsourced manufacturing. Contact him at 215-862-9434; This email address is being protected from spambots. You need JavaScript enabled to view it.; www.spf-inc.com.