Re: Shell Life of Van Dyke Sensitizer

[Brian Ellis <bellis60@earthlink.net>]

At my school we've used Van Dyke brown sensitizer that was more than a year
old without any problems. It was stored in a white plastic bottle that
originally contained stop bath or something like that. In other words, no
great pains were made to preserve it though it was kept in the dark.
----- Original Message -----
From: "Sandy King" <sanking@clemson.edu>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Saturday, August 18, 2001 1:45 PM
Subject: Shell Life of Van Dyke Sensitizer


> Hi folks,
>
> This morning I pulled out an old bottle of Brown Dyke Sensitizer,
> mixed about a year ago, that had been left for many months with a
> small quantity of sensitizer in the bottom, to a depth of about 3/4".
> What I found was a perfectly beautufly coating of silver plating on
> the inside of the bottle (but very shiny when views from the outside
> through the amber colored plastic). Given the fact that the silver
> has left the solution and formed a nice plating on the side of the
> bottle makes it pretty obvious that the shelf life of this particular
> bottle was quite a bit less than a year.
>
> Which brings me to this question. What is the effective shell life of
> Van Dyke sensitizer, assuming that it is kept in a brown, tightly
> capped bottle, and stored at room temperature in the dark, or in very
> subdued light?
>
> Any comments about this, or other specific information about storing
> this sensitizer, appreciated.
>
> Sandy King
>