Hi,
Man! I have tried many, many ways to print Pt/Pd/Au/pigments on glass. And ALMOST NOTHING works well ! Try coating gelatin with Pt/FO. A big mess. I developed the "home made" silane treated PVA that I have described on this forum. But nothing has ever worked as well for me as Kuraray R-Polymer. Brush it on the glass (10% aquious solution -no hardener) dry it, then brush with Pd/Pt/Au or pigment, with the apropriate sensitizer, then expose,develope and clear. No fuss, no muss. Gelatin is a mysterious animal derivative. I have read much, trying to find out just 'What the Hell is Gelatin?" The trueth is- No one realy knows! The stuff changes when you breath on it. And how it changes depends on what you had to drink three hours ago. Besides that, even when hardened, on glass gelatin remains soft and relatively easy to remove from the hard, smooth surface.
Bye
Bill