RE: Making Silver Oxide From Red Devil Lye: Argyrotype

I would certainly have to agree with what Etienne has stated. My last
batch of Argyro (made with Drano) was unstable and produced several
odd and inconsistent results... although I'm now intrigued by the
results. In several instances the hue was quite neutral, with no
warmth at all. If it could be controlled, it might be worthwhile.

next stop Red Devil...

Darryl Baird

-----Original Message-----
From: Etienne Garbaux [mailto:photographeur@softhome.net]
Sent: Mon 9/5/2005 7:08 PM
To: alt-photo-process-l@sask.usask.ca
Subject: Re: Making Silver Oxide From Red Devil Lye: Argyrotype
 
Michael wrote:

> the lye I have on hand is guaranteed 98.5 per cent pure sodium
> hydroxide, marketed as an ingredient for making soap.

> I'm thinking that this must be pure
> enough for this intended use.

Of course, it all depends on what the < 1.5% impurities are and what
process you are doing! But yes, grocery-store lye is generally
perfectly
fine for all photographic uses (as are grocery-store washing soda
[sodium
carbonate], baking soda [sodium bicarbonate], sour salt [citric acid],
and
borax).

My previous message was directed specifically at Drano brand drain
cleaner,
which (in the US) is about 90% sodium hydroxide plus about 10%
aluminum
shavings plus coloring and anti-caking ingredients. It's primarily
the
aluminum that makes Drano unsuitable for photographic uses. When you
put
it in water, the NaOH reacts with the aluminum, giving off hydrogen
gas and
leaving aluminum ions in the solution. The aluminum ions then react
with
other ions in your coating and/or processing chemistry (particularly
those
containing other metal ions), leading to undesired results.

Best regards,

etienne