"Pyrogallol" vs. "Pyrogallol A"

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Hello, The Pyrogallol is not available in my city, but in a chemical store there is a "Pyrogallol A". The salesperson could neither tell the difference between them nor to draw the chemical formula of the "A" modification.

Does anybody know what is "Pyrogallol A"? What is its formula? Is it suited for film development and has it the properties of usual Pyrogallol?

Thanks

-- Andrey Vorobyov (AndreyVorobyov@mail.ru), October 02, 2001

Answers

Pyro formulas come in two parts, usually labelled A and B. A contains the developing agent, and B contains the accellerator. I suspect you have a bottle of A with no B to go with it.

-- Ed Buffaloe (edb@unblinkingeye.com), October 02, 2001.

No Ed, thanks, but I don't think so: it is a _chemical_ store, not a photo store; the sales people there aren't even aware that the pyrogallol can be used as a photo developer.

I browsed my chemical reference books, but could not find any information about such an item. My only hope is that may be there are chemists reading this board that can advice, or may be the "A" is commonly known modification..

-- Andrey Vorobyov (AndreyVorobyov@mail.ru), October 03, 2001.


Andrey, Didn't mean to sound condescending--just trying to help. I wonder if it could stand for acid? Another name for pyrogallol is pyrogallic acid.

-- Ed Buffaloe (edb@unblinkingeye.com), October 03, 2001.

Ed, great idea! In any case I have to buy and to try it: no other way for me to get the pyrogallol. But your last note encourage me :)

Thanks!

-- Andrey Vorobyov (AndreyVorobyov@mail.ru), October 04, 2001.


The Pyrogallol you mention is one of two abalable chemicals, one is for technical use and the other which is more pure or chrystaline for photographic or scientific uses is the anhydrous form, (no water in it's molecule, Pirogallol A.

-- Michael Suarez (Suarez.Michael@EPA.Gov), October 05, 2001.


Pyrogallol is trihydroxybenzen.

-- Vlastik H (Kbear39a@aol.com), November 11, 2001.

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