Old cyanotype chemicals

Discussion in 'Alternative Processes' started by kevin klein, Mar 4, 2014.

  1. kevin klein

    kevin klein Member

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    I have had the same two chems for the past 7 or 8 years, the prints seem to print out slower. What is the useful shelf life of the dry chemicals?
     
  2. cliveh

    cliveh Subscriber

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    If dry powder form and sealed from air, almost indefinitely.
     
  3. Loris Medici

    Loris Medici Member

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    kevin I have 11 years old solutions still working OK. Dry chemicals are stable too - if kept well and incontaminated.
     
  4. Gerald C Koch

    Gerald C Koch Member

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    You don't say what chemicals you have but if they are for the classic process then it depends on the chemical and whether it is in solution or not. I would discard any solutions. Dry potassium ferricyanate will keep. However ferric ammonium citrate may or may not still be good. It must be protested from moisture and light. This chemical should look like green scales.
     
    Last edited by a moderator: Mar 5, 2014
  5. hermit

    hermit Member

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    Kevin;

    I've never had problems with the dry chemicals as I buy them bulk and normally 5 + years before I reorder. Also have had solutions if kept sealed last well over a year with no issues.
     
  6. kevin klein

    kevin klein Member

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    Thanks everyone. I have ordered some Masa and Strathmore 300 scetch paper to try out.
     
  7. Mark_S

    Mark_S Member

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    Kevin

    I have been printing Cyanotypes and getting good results on Rising Stonehenge paper.

    Mark