From: Breukel, C (HKG) (cor@lumc.nl)
Date: 07/18/02-05:18:48 AM Z
Hi Sandy,
Thanks for chiming in (is that the right expression?)..it's good to hear
that PyrocatHD stock is at least stable for 6 months (is this at room
temperature, tightly sealed, or at 4degC?)
On PyroPMK versus ABC+ (aka RolloPyro)..we have discussed this some time
ago, since I ran in to all kind of problems with the stability of stock
"A"of ABC+..I switched to PyroPMK for my JOBO, works perfect. But as
been mentioned before, HP5 does indeed "acquire" quite some B+F
(although I process at 24degC, 1.5* strength PyroPMK, I recently
processed some MACO 820IR, almost no B+F!).
So I might start some testing on Pyrocath , although it is probably wise
to get some fresh pyrocath powder. Using my "inherted" stock of 1954 is
probably asking for trouble..;-)..
Best,
Cor
Sandy King wrote:
>
> 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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