Re: Chrome Alum Gelatin hardener

Oops sorry Ryuji, the j&k keys are next to each other and I have cold
fingers.......thanks for the tech help :)
Kate
----- Original Message -----
From: "Ryuji Suzuki" <rs@silvergrain.org>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Wednesday, February 11, 2004 10:54 AM
Subject: Re: Chrome Alum Gelatin hardener

> From: Kate Mahoney <kateb@paradise.net.nz>
> Subject: Re: Chrome Alum Gelatin hardener
> Date: Wed, 11 Feb 2004 09:25:17 +1300
>
> > What about with gum bichromate, Ryuki?
>
> The answer is I don't know, and it's probably not in literature. There
> are so many organic compounds that can be used to harden gelatin, and
> some of them may have problems with certain dye couplers used in color
> material, some have problems with emulsion coated in alkaline pH, and
> there are a range of compatibility issues, but they are mostly
> empirically discovered and chemically considered afterwards, and as
> far as I know these are all concered about silver gelatin process.
> (except for other fields, such as hardening of gelatin used for hard
> gel capsules.) Then I look deeper into literature and find a longer
> list of hardening compounds, and now a whole list of compounds that
> reduce or remove some undesirable interactions so that the "bad" ones
> can be used, a whole list of hardener enhancing agents so that "bad"
> ones can be used in smaller quantity without reducing the desirable
> effects, etc. Fortunately, I never needed any of those.
>
> BTW My name is Ryuji, not Ryuki. I think I saw someone else saying
> Ryuki before... it's a different name...
>
> --
> Ryuji Suzuki
> "Reality has always had too many heads." (Bob Dylan, Cold Irons Bound,
1997)
>
Received on Tue Feb 10 16:16:16 2004