Feb 7, 2012
In this video blog I discuss a marvelous print sample that was produced by SPC, Specialty Print Communications. What I find particularly interesting about it is how it combines two technologies: high-speed process color inkjet and web offset lithography. With leading edge technologies such as this, you often need a well-designed print sample to show off your new capabilities. SPC does that very well. So first, here are the specifics. On the web offset side, this was done on a Goss Sunday 2000 press using process colors and a 175 line-per-inch halftone screen. The press is also capable of laying down spot gloss, either UV coating or varnish. On the inkjet side, the images were produced by a Kodak Prosper S10 imprinting system set up to produce process color at 600 dots per inch in two 4.16” bands across the page. SPC notes that you need to leave a 4” space between the inkjet bands, which they refer to as channels. The piece was printed on a 7-pt.NewPage TrueJet gloss cover stock.
You need a 4” space between the two inkjet channels because of the way the heads are mounted on the web offset press. If instead you were looking for a wider inkjet channel, or you just wanted to do full variable data with no offset, you’d be more likely to use a dedicated inkjet system rather than an inkjet/offset hybrid. By a dedicated system I mean that rather than having a Kodak S10 Imprinting system you’d have a Kodak Prosper 5000XL or one of its competitors.
So the way that SPC set up this sample was to repeat similar image content across the web. On the left side you see a 4.16” band of variable color imaging with a model, a phone, a car, and other graphics. The same images are repeated in the center, but this time they are produced by web offset. The band on the right shows variable imaging, but this time a UV coat is added over the image area. It will probably be pretty hard to see this on the video, but the addition of this UV coat helps to add some pop and generally improve the perceived image quality.
Comparing the inkjet and web offset side by side, you can see that the web offset image is stronger, has a finer halftone, better detail, and smoother graduated tones. Yet the difference is less noticeable at reading distance. A key differentiator in favor of the inkjet imaging is that it’s variable. Notice the letters in the boxes. These vary from sheet to sheet. So the take-away for me is that high-speed process color inkjet imaging can take place at web offset speeds, and, provide variable data capability.
I’d like to thank Dustin LeFebvre at Specialty Print Communications for sharing this sample with me and allowing InfoTrends to do this video blog. It’s a great sample and I think that it does a wonderful job of showing off the possibilities that hybrid inkjet and offset processes can accomplish.
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