Proper hardener concentrations

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by Hans2008, Oct 7, 2008.

  1. Hans2008

    Hans2008 Member

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    For hardening my emulsions I have only ever used ChromeAlum and Chromium Acetate. The ChromeAlum needs to be used at a weight of 0.5% of the weight of the dissolved gelatin and the Chromium Acetate needs to be used at half that amount.

    I would now like to experiment with Glyoxal ,Gluteraldehyde and Mucobromic Acid. Does anyone know what amounts are best to use for those?
     
  2. Photo Engineer

    Photo Engineer Subscriber

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    I use all hardeners at the same concentration and weight/unit of gelatin. Nothing really critical about them unless you want to control the aldehyde effect on keeping. Aldehydes tend to cause after hardening and also fog emulsions.

    I suggest mucochloric acid over mucoobromic. I also suggest it be used mixed with formalin for best results.

    Actually, I don't suggest Glutaraldehyde due to the extreme toxicity of the fumes. I have read that there are outstanding lawsuits on this over the use of a glutaraldehyde hardening solution for some processes due to toxic reactions by some.

    PE
     
  3. WolfTales

    WolfTales Member

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    Yeah that mucobromic acid gets me every time, especially when I'm congested. :D