ammonium thiocyanate fix

Discussion in 'B&W: Film, Paper, Chemistry' started by Marc Leest, Apr 28, 2009.

  1. Marc Leest

    Marc Leest Member

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    Could a fixer defined from ammonium thiocyanate ? If yes what properties would be prominent ?

    thx, Marc
     
  2. john_s

    john_s Subscriber

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    RA fixers for colour processing contain thiocyanate. You could search for some MSDS documents. I think I read that the fixing is very fast and could be overdone, but I'm not sure. Also more expensive.
     
  3. Ian Grant

    Ian Grant Subscriber

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    Ammonium Thiocyanate was the basis of Stabilisers for rapid access processing, used on their own you don't get good image stability. Used with thiosulphate you will get a super fast rapid fixer which will begin to bleach the image (dissolve the silver) if fixing is prolonged. This of course isn't an issue with Colour materials.

    Ian
     
  4. Mike Wilde

    Mike Wilde Member

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    Our own PE's 'Superfix' uses amm thiocyanate, and it is a super quick fixer.
     
  5. CBG

    CBG Member

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  6. Ian Grant

    Ian Grant Subscriber

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    Virtually all rapid fixers are ammonium based, usually using Ammonium Thiosulphate, although older formulae used Sodium Thiosulphate with Ammonium Chloride.

    Hover the linked formula isn't based on Ammonium Thiocyanate which was the OP's question :D

    Ian