Use of opaque and non-opaque colour inks

Hi all,

I have just started to experiment with multiple colour output on my Adana Eight-Five, after purchasing tubes of blue, red, yellow and opaque white. The first thing I realised when applying the three primary colours onto the inking disk, was that, unlike black, they were not opaque, and I could see scratches on the inking disk showing through. This has enabled me to get some good results by overlaying multiple coloured text to gain a third colour where they overlap.

I would however sometimes, like to be able to block out an overlapping colour completely. How would I do this ? My ink supplier did not specify the coloured inks as either opaque or non-opaque, but did offer the option for white. Are opaque colours for letterpress widely available, or do I just use an opaque white base and add the other colours to that ?

Any advice gratefully received as always.

Regards,

Ian.

Log in to reply   4 replies so far

i am no expert by any means, but as far as i know, there aren’t really any true ‘opaque’ inks because of the thin layer in which they are applied. the only reason why black seem so opaque is because it is black and you just can’t really tell if there are color overlays

Hi WillyP

I’ve just located a previous similar thread which suggests it is worth mixing colours with a white opaque base, to see if it gives the desired effect.

I’ll add another post, with the results…

Printmonkey

There are ways to overprint and completely block the color underneath - these would include screen printing, foil stamping, and perhaps thermograving - but it’s usually not realistic to expect a complete blockout with letterpress.

As you discovered and WillyP says, most inks are basically transparent or at least translucent (the exceptions might be tmetallic silver or gold). Even when mixed with Opaque White, inks laid down by letterpress are still a thin enough layer that you’ll most likely get at least some show-through. Doing an additional press run in a silver or gold blockout, or simply a second run (another layer) of the top color, may work but requires precise register in addition to the extra work. Usually the artwork is simply prepared with a “knockout” of the first color where the second overlaps, sometimes with a bit of trapping where the colors meet so the paper doesn’t show through if registration is off a tiny bit - and yes, knockouts require precise registration also.

A simpler approach is to design for the “third color” where two colors overlap, as you’ve noted, or design to avoid overlaps, or just accept that even “opaque” inks aren’t completely opaque.

Dave (the Ink in Tubes guy)

Hi Dave,

Many thanks for the useful advice. I’ll concentrate on the third-colour approach, as this seems a far more natural way to work with, and not against the letterpress medium. I’m pretty pleased with the results obtained so far.

Regards,

Ian.