Re: oil-print-glyoxal??

From: Katharine Thayer <kthayer@pacifier.com>
Subject: Re: oil-print-glyoxal??
Date: Mon, 27 Dec 2004 20:08:28 +0000

> Yes, he was worried about mold/bacteria, but only in the highlights
> where the gelatin would not be crosslinked by the dichromate/exposure.
> The crucial distinction here, I believe, is not swollen vs not swollen,
> but crosslinked vs not crosslinked. Yes, the two conditions overlap to a
> considerable extent but they aren't idempotent. For example, when the
> water evaporates, the swelling will go away but the gelatin still won't
> be crosslinked.

I don't think crosslinking eliminates mold growth. Biocides are used
in addition to hardening. If the risk of mold growth is real, I don't
think there is any better option than to use a suitable biocide.

Crosslinking of gelatin molecules has little effect when the gelatin
is dry. The property of gelatin in dry state is influenced strongly by
the condition how the gelatin dispersion was dried.

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