Homebrew PCBs

David Griffith wrote:
> On Sat, 19 Nov 2005, Russell Shaw wrote:
> 
>>David Griffith wrote:
>>
>>>I've acquired a roll of liquidated Aqua-Mer PR photoresist film that I
>>>intend to cut up into smaller quantities for sale on Ebay (toot! toot!).
>>>My question: what is the correct developer?  I picked up a bottle from a
>>>downtown shop that turned out to be a sodium hydroxide solution, which I'd
>>>rather not mess with given that it's relatively unforgiving with
>>>overdevelopment.
>>
>>Sodium hydroxide is stripper. Try 10g/L sodium carbonate at 25-30degC.
> 
> I remember sodium silicate being referenced as a developer.  Is that only
> for positive spray resist?

It may work too. I'm not so familiar with all the chemical alternatives.
I couldn't find references on google. To use sodium silicate for positive
resist, it can be mixed with sodium hydroxide:

   http://members.lycos.nl/anthonyvh/index.php?page=pcb