Re: Pyro for TP

Larry Bullis (lbullis@ctc.ctc.edu)
Fri, 16 Jan 1998 09:01:51 -0800

>5g Phenidone*
>2g Sodiumbisulfite
>5g Pyrogallic acid
>0,5g EDTA-Na4
>dissolved in 100ml distilled water
>
>*This makes only a suspension because the Phenidone donīt solves completely

Then there's no point in spending the money for it. You can get it to dissolve, though, and it's worth doing. Try 1) dissolving the bisulphite first, then the phenidone and 2) dissolve the phenidone in boiling water (yes, I mean it). You would then need to cool the phenidone/bisulphite solution before adding the pyro, which would probably not survive the hot water.

Acufine, a developer I used to swear simply didn't work, actually does. However, if you follow the mixing directions, the phenidone does not go into solution, and it performs poorly. If you mix it in boiling water, it's great.

Phenidone is wonderful, but getting it to dissolve is always a problem. In his _105[?] Formulas_ book Dignan had a section about it. I have it somewhere.

Larry Bullis
Skagit Valley College