Motif,
Look here,
http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/26532and in particular at this patent,
IMAGE-FORMING PROCESS 5556735 (Google Patents)
The only sensitizer, other than one of the dichromates, that an individual can buy is diazo. I don't know if diazo will work with gum, but it does work with PVA/PVAac emulsions. Search for Speedball Diazo. There are a lot of patents for sensitizers, but you need a PhD in organic chemistry to understand them.
Baxter
> 1) I would like to know is there any alternative which is more safe, easily available and economical when compared to potassium/ammonium bichromate? I don't want to go for toner transfer or dry film option, only photo-resists.
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