Re: WAS: oil-print-glyoxal?? NOW: Halide Composition of Bottled Emulsions

From: Bill William <iodideshi@yahoo.co.jp>
Subject: WAS: oil-print-glyoxal?? NOW: Halide Composition of Bottled Emulsions
Date: Tue, 28 Dec 2004 22:08:06 +0900 (JST)

> Since we are discussing coating trouble on paper with
> different degrees of sizing, I do not understand why you
> felt it necessary to discuss the halides actually used
> liquid emulsions (AgClBr or Ag BrI) The precise halide
> content is totally irrelevant, but since you did bring it
> up:

It is very relevant. AgCl and AgBr have an important difference in
their Ag-AgX electrode potential. They also have different ksp values
and different ranges of pAg they often operate at. These differences
give rise to different reactivity or susceptibility to a lot of
things, including reactions when the emulsion comes in contact with
watercolor paper. Chlorobromide emulsions are a lot more fastidious.

--
Ryuji Suzuki
"People seldom do what they believe in.  They do what is convenient,
then repent." (Bob Dylan, Brownsville Girl, 1986)