Just to have one post today on the subject. Are there any new
results?
I did come across this during a discussion on another group:
Sodium Persulfate is a good replacement for Ammonium Persulfate for
its compatibility with etch resist pens. Sodium Persulfate will not
remove etch resist ink and like Ammonium Persulfate crystals, are
used as an alternative to the traditional ferric chloride to produce
a cleaner copper etchant solution.
Here's the link:
http://www.mgchemicals.com/products/4101.htmlSomething to be considered down the line. I did notice how fragile
the Durabrite ink ws in both FeCL and HCl/H2O2 etches. I did not try
Ammonium Persulfate.
Myc