Homebrew PCBs

Thanks for the clarification. I had misunderstood what you were 
saying. I'm a bit surprised that screen cleaner attacks copper since 
it's used to clean aluminimum-framed screens. I suppose that it 
could weaken the bond between the copper and the laminate though.


Regards, Bob

--- In Homebrew_PCBs@yahoogroups.com, "hjf2k2" <drgenio@h...> wrote:
> sorry, I didn't express myself clearly. the residue is there after
> developing but before going into ferric chloride.
> 
> to finally remove the emulsion, i do use screen cleaner. but it 
seems
> to attack copper. i was told to use bleach or sodium hydroxide 
which
> can remove the emulsion and won't attack copper... but I'm not so 
sure
> about that. I use paint thinner and a little more work, and it goes
> away, and thinner surely doesn't attack copper.
> 
> regards,
> hernan
>