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Subject: Re: Water glass etch resist

From: "pebo festus" <mebo31@...>
Date: 2004-01-17

--- In Homebrew_PCBs@yahoogroups.com, Adam Seychell
<adam_seychell@y...> wrote:

> The sodium silicates are alkaline, so any contact from acidic
> copper etchants will only neutralize and you end up with a
> solution of silica gel (colloidal SiO2) and the salt.

adam are you telling me that even if the water glass is set and hard
the acids wiil desolve it?. i have been advised that gycol and water
glass will also harden if mixed, will the acids soften this combo
also?.

i was toying with the idea of coating the pcb with water glass and
print with glycol. or maybe the other way around, coating with gylcol
and printing with water glass. there just has to be a better way.
mebo