For those who are interested in printing Pt/Pd/Au/pigment on glass, there is a silane functional PVOH polymer which can be purchased in the USA. I have compared it to the Subbing that I have published on this Forum and on alternativephotography.com. The commercial polymer is water clear and adheres to glass tenaciously. It can be brushed with Pd/FAO solution and imaged the same as on paper. So far, it appears to be superior to my home-made subbing in all ways.
KURARAY R-POLYMER;KUARAY AMERICA;www.kuraray-am.com;713-495-7381
Bill