[pure-silver] Re: Fishy developer: NOW Triethanolamine
- From: "John Black" <jblack@xxxxxxxxx>
- To: <pure-silver@xxxxxxxxxxxxx>
- Date: Fri, 17 Dec 2004 15:11:23 -0500
> One doesn't have to use straight TEA as the solvent in the Gainer formula.
The
> solvent could be and mixture of TEA and propylene glycol or something
similar.
> This would drop the pH of the concentrate and also the working solution.
>
> Jerry
>
Correct. Gainer showed that any of the glycols and/or TEA would work as a
solvent for the reactants. However, he did like using only TEA as solvent
and pH control for the sake of simplicity. TEA liquid is a viscous liquid
and I, for one, dislike using it because it is difficult to measue
accurately. If the TEA is diluted 1+1 (1:2) with methanol, it become fluid
and is much easier to handle.
I doubt that there would be sufficient interaction between TEA and the
glycols to form a buffer.
BTW, as an aside, my favorite developer is a PC using Tris-amino
methane/boric acid as a buffer (pH 8.3). The PC is dissolved in dry methanol
(wood alcohol) as the solution A. I dissolve 10gm ascorbic acid in 120ml
methanol first and then 250mg phenidone. Ascorbic acid is soluble with
gentle heat (80-100 degrees) in methanol up to the saturation point which is
between 9 and 10gm per 100ml. I found the other night, that sodium ascorbate
(the neutralized form of vitamin C used in Xtol) is essentially insoluble in
methanol at any temperature. So that eliminates sodium ascorbate from my
formulas.
Oh well... next I will see if I can put a small amount of hydroquinone in
there and boost shadow detail a bit.
JB
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