From: stan johnson (sjohnson@gwi.net)
Date: 04/07/00-01:50:44 PM Z
** Reply to note from Judy Seigel <jseigel@panix.com> Thu, 06 Apr
2000 21:57:31 -0400 (EDT)
> In any event, and whichever, note that sodium *sulfide* is the stinky
> stuff used in toners. Sodium *sulfite* is the silver solvent, also
> ingredient in clearing baths & developers.
And while sulfide is mildly alkaline in water solution, as is sulfite,
bisulfate [better known as (sodium e.g.) hydrogen sulfate] is quite
strongly acid in water solution. Bisulfite [again, better called hydrogen
sulfite] is also [but less] acid, IIRC.
So, since sulfate ion is photographically pretty much inert, sodium or
potassium hydrogen sulfate is a convenient and quite safe way of
getting a fairly acid solution [and thus, as Judy pointed out off-list,
often used as a substitute for sulfuric acid] without any powerful
photographic actions that I'm aware of, aside from the pH effect.
I'm not a photochemist, so I could be unaware of some problems. But
in this case, I doubt it--this is pretty straightforward stuff.
stan
-- Stan Johnson sjohnson@gwi.net 04/06/00 10:48pm
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