From: Rocky (rocky@pdq.net)
Date: 07/17/02-09:08:03 AM Z
I have recently returned to the list after a short absence and am unfamilar
with the details of the following:
"Just look at all the discussion about this problem with regard to Xtol."
Could someone please fill me in or direct me to the proper archive
information. I find the archives difficult to search and the downloaded
version I got stopped in 1998. Perhaps I am doing something wrong.
Thanks,
Rocky
Houston,TX
----- Original Message -----
From: "Sandy King" <sanking@clemson.edu>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Wednesday, July 17, 2002 8:59 AM
Subject: Re: HP5+ and LONG development times
> Cor wrote:
>
>
> >
> >I seem to recall that this developer isn't very stable (the mixed stocks
> >I mean).
> >Is this also your experience? And if the Pyrocat stock goes "bad",
> >you'll notice it by it's colour change?
> >
> >PMK Pyro is reported to be very stable (stocks), so that is an advantage
> >for a low volume shooter like me.
> >
> >Best,
> >
> >Cor
>
>
>
>
> --
> You may have confused reports about the stability of ABC+/Rollo Pyro
> with Pyrocat-HD.
>
> As regards ABC+/Rollo Pyro I have heard quite a number of negative
> reports about the stability of the stock solutions, or more
> specifically, stock solution A. The issue is that that the developer
> appears to lose a lot of its energy after a few months of storage.
> The likely culprit is ascorbic acid, which is known to go bad in
> certain kinds of stock solutions. Just look at all the discussion
> about this problem with regard to Xtol.
>
> As for Pyrocat-HD I have suggested in various places that the
> stability of Stock Solution A, when the formula contains phenidone,
> is not as great as the stability Stock Solution A of PMK, which as we
> know can last for years. When I initially made this suggestion it was
> based on theory. However, after working with Pyrocat-HD for a number
> of years I can state as a fact that Stock Solution A, with
> Phenidoine, is good for up to 6 months, with proper storage. Not as
> good as PMK but as good or better than most all other developers.
> With metol in place of phenidone stability is even better.
>
> Sandy King
>
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