High concentrations are definitely nasty. The stuff heats up on it's
own then and releases lotsa fumes. I've tried with a tiny amount once
and after only 10 seconds immersion the board I inserted was etched
clean, including much of the resist covered traces ;-)
I think the thermal runaway is even worse with sulphuric peroxy stuff.
Not a problem with reasonable concentrations, even less so as you
develop towards CuCl.
ST
On Wed, Feb 3, 2010 at 2:50 PM, Philip Pemberton <ygroups@...> wrote:
> Academic point, really. I'd be more worried about high-concentration
> HCl+H2O2 -- isn't that a so-called "piranha acid" mix, or am I thinking
> of something else?
>