Cyanotype discoloration on sensitized paper?

Discussion in 'Alternative Processes' started by Dante Stella, Apr 27, 2009.

  1. Dante Stella

    Dante Stella Member

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    I'm a little puzzled - with the regular cyanotype process, I am getting green streaks on sensitized (but not exposed) paper when it dries. The only way to avoid this seems to be to force-dry the paper and to expose it quickly (i.e., within about half an hour).

    Ideas? The only thing I can think of its that it may be streaking of too much sensitizer, although this is a low-penetration paper (Arches Plaine) and there is no visible unevenness in wetness when the paper is put out to dry.

    Thanks
    Dante
     
  2. Akki14

    Akki14 Member

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    If it's slightly shiny and tacky it's too much sensitiser, otherwise your paper is probably too buffered/alkaline and might need a soak in a weak acid bath and dried before you coat.
     
  3. nze

    nze Member

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    As Heather wrote this happen with too buffered paper. You should adicify your paper or change of brand.
     
  4. Jim Noel

    Jim Noel Member

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    it sounds very much like you are using a buffered paper, which probably means that it is too alkaline.
    use a 100% cotton or rag paper. It should be neutral or even better, slightly acidic.
     
  5. FredW

    FredW Member

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    So that was my problem with platine. I had found the image floated off the surface of Platine. Thanks.