Ethyl alcohol does not thicken the solution, but thins it. Or at least decreases it's surface tension. I use 190 proof Everclear from the liquor store. I use the equivalent of about 5 drops per 2 ml of sensitizer (pt/pd + ferric). It has proven beneficial to smooth, even coatings on every paper I've used it with, although I've never been interested in printing on fixed out silver paper, so I can't comment on that. I also add it to my gum dichromate solutions to add in smooth, even coatings. If things go bad, I add it to my coffee to smooth my attitude!
Originally Posted by Craig Koshyk