Stonehenge is not something that we really use much with PD/PT either, but like I mentioned in another post, we joke this is a 'paper saver' because it sits on the surface, it can greatly change the paper character for alt printing.
Regarding mechanical stability, i've never been able to see my fingerprints on the paper (it's kinda like a lustre finish). Of course, I also wasn't eating potato chips either at the time. For spotting, we've used the same dyes, knife methods as one would perform on traditional prints with no ill-effect. Is there a specific test you would be interested in me performing?
A little history: this type of coating was used heavily back in the day of blueprints. The patents show that the companies used it for increased contrast, sharpness, and paper stability. I have no way to guess how many millions of square feet this stuff was used, but some of the largest cyano companies employed this technique. In fact, we are doing some testing on a new paper that seems they might have caught wind and started applying this as well.
Last edited by Klainmeister; 08-15-2013 at 12:28 PM. Click to view previous post history.