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Subject: Re: [Homebrew_PCBs] Re: Newbie questions

From: Adam Seychell <a_seychell@...>
Date: 2007-04-12

Andrew wrote:
>
>
> > Russell wrote:
> >
> > I use 10% Na2CO3 sodium carbonate for
> > the developing. Unlike NaOH, it's much
> > less reactive to skin.
>
> Does anyone use sodium silcate?
>
> I beleive that is what is in the little
> packets I get from computronics.

Positive resists use a much stronger alkaline developer, like 1% NaOH or
Na2SO3. Negative dryfilm resist require a much gentler alkaline like 1%
Na2CO3. I gave up on positive resists years ago, but been told silicate
is much easer to use than the hydroxide.