What are the chemicals in solargraphic paper?

Discussion in 'B&W: Film, Paper, Chemistry' started by amuderick, Sep 20, 2008.

  1. amuderick

    amuderick Member

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    They sell paper with a blue coating in kids stores. It comes in a black bag. You put it in the sun with various things on top of it and where the sun hits (UV-light), it turns white. When you wash the paper in water, the reaction becomes fixed. What is the formula?
     
  2. Photo Engineer

    Photo Engineer Subscriber

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    Sounds like cyanotype. Formulas for that are all over the photo sites. The Formulary sells kits.

    PE
     
  3. psvensson

    psvensson Member

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    Yup, the solargraphic kits seem to be the very simplest form of cyanotype: potassium ferricyanide plus ferric ammonium citrate. They're nearly harmless and easily mixed from scratch.