Re: Move to synthetic materials (from versatile surfactant_

Agar is a carbohydrate--kind of like a specialized starch. It's kind of
cool. It melts at near boiling, but is liquid to about 100 F. You then
need to re-boil to re-melt. If it is applicable it could be used both as a
substitute for gelatin, or as a layer under the gelatin. As it has a much
higher melting point, the gelatin would fall off, long before the agar.
It's available in many grades of refinement (look it up in VWR or Sigma).

It comes from seaweed. It is used in everything from the plates for growing
bacteria up to a thickener for ice cream.

----- Original Message -----
From: "Ryuji Suzuki" <rs@silvergrain.org>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Sunday, January 16, 2005 10:10 PM
Subject: Re: Move to synthetic materials (from versatile surfactant_

> From: Martin Angerman <paleophoto@adelphia.net>
> Subject: Move to synthetic materials (from versatile surfactant_
> Date: Sun, 16 Jan 2005 18:33:41 -0800
>
> > Has anyone tried agar or agarose?
>
> No... does it have any reducing effect? (which would fog the emulsion)
>
> > Polyacrylamide is also interesting, but the monomer is a nasty toxic.
>
> It's a pretty common blend to gelatin in silver gelatin, but securing
> good adhesion seems to be a bit problematic.
>
> --
> Ryuji Suzuki
> "People seldom do what they believe in. They do what is convenient,
> then repent." (Bob Dylan, Brownsville Girl, 1986)
Received on Mon Jan 17 09:29:45 2005