RE: Gum problem(s)

If it can serve the same purpose as Photoflo / Ilfotol, then maybe it's
better to use alcohol because it disappears (no alien compounds in the
hardened emulsion).

Thanks Henk and Tom,
Loris.

-----Original Message-----
From: Tom Sobota [mailto:tsobota@teleline.es]
Sent: 18 Kasım 2005 Cuma 20:23
To: alt-photo-process-l@sask.usask.ca
Subject: RE: Gum problem(s)

Loris,

Alcohol (or acetone) is used in other processes (i.e. carbon) to speed
up drying of the sensibilized couch so I don't think that it will react
in any way with the dichromated gum mixture. Not being a chemist I
cannot swear to this. However, experience suggests that alcohol will
evaporate rather quickly without reacting with anything.

Alcohol has a low superficial tension, so it's effects seem to be more
or less equivalent with those of a surfactant such as Photoflo. However,
alcohol will eventually disappear while the surfactant stays in the
mixture. This will, or will not, make a difference. I don't know.

Regards
Tom

At 17:52 18/11/2005, you wrote:
>Can one add pure alcohol instead of Tween or Photoflo/Ilfotol to
>facilitate coating of gum emulsion? Will alcohol get in reaction with
>dichromate and/or colloid?
Received on Fri Nov 18 12:32:25 2005