In one sense, the stamping, coating, laminating and otherwise finishing of labels and other packaging that have been digitally printed can be likened to Donald Rumsfeld’s famous quote about “unknown unknowns.” There’s a lot that we don’t even know that we don’t know about the whole process. To that end, a 2011 IADD*FSEA Odyssey session Friday, co-sponsored by the Printing Industries of the South (PIAS), analyzed the “Impact of Digital Printing Technology on Finishing and Packaging.” The four panelists included Roy Oomen, label and packaging solutions manager at HP Indigo; David Hutchison of converter BrightMARKS LLC; Mark Coalson, wide-format laminating manager at Transilwrap; and Jeff Higgins, president of converter Colorstream Digital.
“Known knowns” and tips for converters: Here are some bullet points to help you deal with problems emerging from this breaking technology.
- Know your print methods and print engine—inkjet, toner, manufacturer; evaluate the expected result—pre-process and post-process—for what your customer wants completely through to the end-user’s environment—retail or industrial.
- Don’t avoid anything and evaluate everything; problems come from not knowing your goals and not pre-planning enough.
- Digital printing is like laying down a lamination of ink, so think in terms of coatweights. The digital-ink layer on top of paper or board distorts the level plane for proper foil attachment. There are options to help fatten up the stamping area to improve this.
- Consider corona treatment to boost adhesion of foils and UV coatings; treat to 40-42 dyne level. But remember that corona treatment and the fusing of digital inks can sometimes discolor the product—test 50/100 sheets to see what your exposure to problems might be.
- Dryers mounted after the digital press accelerate curing prior to rewinding.
- Use UV lamps to flash off any residual oils before UV coating and final curing.
- Assume there likely will be registration problems, so warn your customers.
- Not all laminating films are over-stampable; first-generation digital printing requires lower-temp films of 185-190 deg F; test, test, test along the way.
- Save your spoilage to send back to the digital printer so they know what was bad and when it happened in the load.
- Take advantage of the FSEA Big List—an email-based, semi-technical, blogging tool is a great resource. Questions go out to 200 member recipients who might be able to help.
- Certified partners are available to assist (particularly for HP Indigo-printed materials), among them: ITW Foilmark (stamping); AB Graphic, Delta Industrial, Brausse and KAMA (diecutting, folding/gluing); Gould Paper and Masterpiece (12- to 18-pt coated paperboards); and EskoArtwork (prepress).