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  1. #41
    gainer's Avatar
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    I know from experience that PMK lives forever, along with Rodinal and HC110. Pyrocat in the original formula is no slouch either. Xtol does not, so it depends on how fast you can use it. I tried it when it first came out, before all the hubbub about it's failing without warning. Now the package is too big. I can make a stock that is as concentrated as HC110 or Rodinal, that has fine grain and high sharpness, and that will be ready to go when I want it. It can be a staining developer or not. I can even use hydroquinone as a staining developer.

    The worst part of it is that I'm not making any coin of the realm by doing it. I'm surely having fun, though.
    Gadget Gainer

  2. #42

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    Quote Originally Posted by gainer
    Sandy,
    I don't remember if you reported the effects of using benzotriazole in place of bromide. If it works, is it more easily soluble in glycol?
    OK, I finally got around to testing this. The anwer is yes, benzotriazole is much more soluble in glycol than potassium bromide. In percent solutions ranging from 1-5% benzotriazole goes into solution quite readily in glycol at a relatively low temperaature, i.e. 170º F or less.


    This worked for me with both dipropylene glycol and propylene glycol in the percentages noted above.

    At some point in the future I will do some tests to establish an equivalent substitution of benzotriazole for potassium bromide. Meanwhile, just mix in the potassium bromide with the glycol at about 250º F and stir until it goes into solution.

    Sandy

  3. #43
    gainer's Avatar
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    I'm glad to hear about benzotriazole. I looked at my tincture of iodine, and it is 2% iodine and 2.4% sodium iodide in a 60% alcohol solution. Povidone is 1% available iodine and seems to dissolve easily in glycol or TEA. I did a R&D test with it (that means rough and dirty) but I can see it will take a lot of careful trials to find out if it is worth using and if so, how much. The references I found reported that iodide is much more active than bromide, that a very small concentration could shorten the induction period of hydroquinone, but no quantitative information.
    Last edited by gainer; 12-29-2004 at 12:01 AM. Click to view previous post history. Reason: Need to change a word.
    Gadget Gainer

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