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Thread: Catechol, Catechol, Pyrocatechol?

  1. #1
    Ross
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    May 2004
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    Blue Mountains NSW
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    Catechol, Catechol, Pyrocatechol?

    Stephen Anchell in the Cookbook says that these are synonymous.

    My first mix of Pyrocat HD was from a Formulary kit as a trial.

    It looked promising, so i ordered the makings from my local supplier.

    However the "catechol" looked different to Formulary's. Theirs was a rather odd collection of differently shaped crystals and powder, with a distinctly brown tone.

    My supplier's was a far cleaner looking and more regular small crystalline glossy one, with a slight touch of brown.

    As well by a rough calculation Formulary's price is 8 cents/gram and my local's 52 cents/gram.

    The purchase has been made, it's not an option to return the catechol, but I'd appreciate confirmation that this is probably just a higher grade, and that the synonymity quoted above is correct and -- as far as limited e-mail communication allows -- it will work?

    Regards - Ross

  2. #2
    Ross
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    Blue Mountains NSW
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    Re: Catechol, Catechol, Pyrocatechol?

    Whoops, Header should have been:

    Catechol, Catechin, Pyrocatechol?

    You may observe my confusion :-)

    Ross

  3. #3
    All metric sizes to 24x30 Ole Tjugen's Avatar
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    Re: Catechol, Catechol, Pyrocatechol?

    It's the same. 1,2 benzenediol and o-hydroxyphenol are also the same.

    I've used the "high grade stuff" for years, since with shipping it ends up being cheaper than the Formulary's.

  4. #4
    IanG's Avatar
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    Re: Catechol, Catechol, Pyrocatechol?

    Also know as Pyrocatechin. It should be white crystals with a pinkish touch.

    Once it goes a grey/brown it's usually old and unuseable, so always worth doing some tests first before trusting it for important films. However yours sounds fine and as it should be.

    Ian

  5. #5
    Ross
    Join Date
    May 2004
    Location
    Blue Mountains NSW
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    Re: Catechol, Catechol, Pyrocatechol?

    Thanks for the prompt answer. You may picture me at my suppliers (who seemed to have also multiplied the ordered quantity by 5 somehow) backing out of a $300 bill, when Formulary prices were so much lower comparatively. Fortunately we have a good relationship! The Formulary catechin did look rather like something swept from the floor, but worked fine. I understand that there are "analytical" and "technical" grades of chemistry, with markedly different prices?

    Thanks - Ross

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