Unfortunately this stuff is a bit hard to get: I found a rather obscure
source for it in the Directory of World Chemical Producers:
Urals Plant of of Chemical Reagents
ul. Lenina
624.080 Verkhnjay Pyshma, Sverdlovskaja obl., Russia
Dick Sullivan told me he located an American source: Pfalts & Bauer, 172
E.Aurora St., Waterbury Ct. 06708, 203,-574-3181.
Dick, did this pan out, or was it simpy too expensive to bother with?
It would be a lot easier to make up, but maybe it's a bit too much to pay
for the convenience.
Re the citric acid wash - it probably depends a lot on your water supply to
start with.
The following from an e-mail exchange with Mike Ware might be of interest:
>Not long ago I posted some test results for a citric acid wash for new
>cyanotype, and have been meaning to compare whether it makes quite the same
>vivid blue difference with the traditional sensitiser. One problem I
>reported (and Judy also seems to have experienced) is that Prussian Blue
>particles seem to be quite concentrated in the citric acid wash, and tend
to
>degrade the whites or the back of the paper. Have you come across this at
>all too?
Yes, there is always some runoff of Prussian blue (but it's minimised if
the print is properly masked) depending on the paper/wetting agent
combination, and this pigment will accumulate as a sol in the first bath, if
that is a
static one, and stain subsequent prints. The only answer is to replace the
citric bath quite frequently or to use an ordinary running water dev/wash,
which usually provides a big enough Dmax anyway.
BTW, I have also found that the 'intensifying' acid doesn't have to be
citric - probably any acid will do. I have used 1% v/v hydrochloric acid
(10 cc of concentrated acid to 1 litre of water) which intensifies even
more than 2% citric, and is much cheaper. Feel free to pass on this
observation to anyone who might be interested. It is possible that the
hydrochloric acid could be more dilute and still effective at say 0.1% - I
haven't tried it yet.
<end quote from Mike>
All the best to everybody for the anno nuovo,
Philip Jackson
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