[pure-silver] Re: Anti-Silvering Agent
- From: Jordan Wosnick <jwosnick@xxxxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Tue, 01 May 2007 20:28:47 -0400
Chlororesorcinol probably smells -- a very "chemical"-like, somewhat
phenolic smell. The parent (resorcinol) certainly smells and I'm pretty
sure that bromoresorcinol smells too.
Anyone know if Microdol-X (the powder) smells?
Richard Knoppow wrote:
I've come across another patent that may be of some interest to the group. This one is USP 3,161,524 issued to Richard W. Henn and assigned to Eastman Kodak. In it Henn describes the use of Chlororesorcinol as a silver sequestering agent to prevent dichroic fog. He gives results using high solvent developers, in particular Kodak D-25 with and without the addition of the Chlororesorcinol which show that a relatively small amount of this substance completely eliminates the deposition of silver on the surfaces of high speed film.
I think it is possible that Chlororesorcinol may be the "X" in Microdol-X and its presence may be the difference between T-Max developer and T-Max RS. Kodak does not recommend the use of T-Max for sheet film due to dichroic fog.
Those with a better knowledge of photographic chemistry than I may want to have a look at this patent.
--
Richard Knoppow
dickburk@xxxxxxxxxxxxx
Los Angeles, CA, USA
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Jordan Wosnick
jwosnick@xxxxxxxxxxx
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