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  1. #21

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    I'm curious if is paper, cloth, rubber, sponge or something else. A woven belt might leave a texture but could have an advantage of being nicely porous.

  2. #22
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    It was thick gelatin on film support imbibed with a monobath containing a release agent.

    PE

  3. #23

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    This is a great post a lot of info I will be reading this for a long time.

  4. #24

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    Grant Haist also talks about a PVC belt saturated in the monobath. Barnes and Johnston (Kodak patent) discuss adding nuclei to the monobath and raising the pH to 12 to make it work in seconds. I wonder how fast that BIMAT belt traveled?

  5. #25
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    IIRC, the PVC came loose as it could not be hardened. IDK for sure how fast the belt traveled. I know that processing only took seconds. See the equipment on display at GEH.

    PE

  6. #26
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    I've always wondered about Donald Quall's. He seems to be a prominent figure in the analog world and occasionally I find posts of his on APUG. His monobath is very interesting too. Is he still around?

    Following the 55 project has been fun; always a pleasure to see things moving/shaking over there. Best wishes!
    If you are the big tree, we are the small axe

  7. #27
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    Quote Originally Posted by BobCrowley View Post
    ...then topcoat with release agent (soap).
    Bob,

    Could you share any details of this release agent? I'm looking for a method to bind two sheets of film in optical contact so that they can be released from each other easily. One sheet would be a processed sheet of slide film (screen-plate w/ TV-screen reseau) and the other would be a sheet of b&w film.

    In old bi-pack & tri-packs there were patents and methods that used soap to bind the different layers. Right now I'm using gelatin w/ sorbitol which works, but is not yet ideal.
    If you are the big tree, we are the small axe

  8. #28

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    Right at this moment I have samples on the bench drying with acacia/gum arabic as the release layer on two different papers. Gum arabic is nice stuff, shiny, smooth and clear, but also brittle if too thick, and needs to be dissolved in water once dried to peel away. If your layers can be soaked, maybe that will work. In our application the gum arabic presumably sits on top and never gets a chance to dry and stick.

    Otherwise I have no idea: maybe you could look at some transparent tacky polymer, such as silicone, (not the kind with acetic acid, but the type used for fishtanks) if you don't need a strong bond and need to peel it. You might need a release layer for your release layer, perhaps a light film of silicone oil on one of the surfaces adjacent to the cured silicone, so it will peel away.

    What's the adhesive used in clear packing tape? That peels, and is clear.

  9. #29
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    Try Caboxy Methyl Cellulose.

    PE

  10. #30

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    We've made a bit of progress

    http://new55project.blogspot.com

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