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  1. #1

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    Polyacrylamide Gels & Resins

    I have been snooping around in the Kodak paper patents this morning at freepatentsonline and among the list of their sizing materials for increasing wet strength and smoothness are polyacrylamide gels and resins... does anyone happen to know where I can get some in small quantities... does anyone know about their solubility when dry... anyone tested these? Thanks!

  2. #2
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    Annie, using them for sizing anything that needs to be wet processed will result in the coating sliding off the support.

    You cannot harden most of those compounds. Unless the polymer is specifically hardenable, it is not suitable. I was never able to harden polyacrylamide.

    It is usable for ink jet work and for instant imaging as the ressults never get wet enough, but if you wet some inkjet papers, they slide off the support as well. I've done it.

    PE

  3. #3

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    Rats!! Thanks PE!!

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    Annie, been thinking about this. I realized that I should have mentioned that these polymers can be mixed with gelatin and sometimes you get the best of both worlds.

    So, let me encourage you to do some experimentation. Who knows.....

    PE

  5. #5

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    Yikes... only 27 views all day and most of them mine ... I must be the Queen of the Ignore Lists... sheesh.... guess it's back to whipping up egg whites maybe I'll add a little celquat this time!! cheers... hmmmm...anyone doing an albumen layer size under Pt??

  6. #6

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    PE ... my only APUG photo pal!! I have been thinking about this also and I discovered that polyacrylamide is also used in plant hydration and you can get it in small quantities at garden shops... I am going to try just a touch with a modified albumen size I am messing with and see what happens... so far with the albumen I have been able to bump up the Dmax a touch on a very smooth extinct Kodak paper I am using for Pt.... wish me luck!

  7. #7
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    Luck Annie.

    Keep in touch. I'll try to help where possible.

    Never give up. In photography, things are never as they first seem. The phase of the moon keeps changing. ~smiles and grins~.

    PE

  8. #8

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    Polywhoziwhatzit? Can someone post a brief explaination of what these are and why they are important for alt photo? I'm only familiar with gelatin sizing. Thanks!

  9. #9

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    Quote Originally Posted by Photo Engineer
    Annie, using them for sizing anything that needs to be wet processed will result in the coating sliding off the support.

    You cannot harden most of those compounds. Unless the polymer is specifically hardenable, it is not suitable. I was never able to harden polyacrylamide.

    It is usable for ink jet work and for instant imaging as the ressults never get wet enough, but if you wet some inkjet papers, they slide off the support as well. I've done it.

    PE
    How is the polyacrilamide when dry? This might be a good coating for dried prints to bring back the "life" they have when they are wet. This of course if it does not yellow out, which I have the feeling many acrylates do....

  10. #10
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    Guys, many polymers can be substituted for gelatin in photo products. The problem is that they must be hardenable to survive the wet processing steps or they can be washed off the support.

    Being hardenable is not normally the case. So, they must be chemically tailored for allowing hardening to take place. For example, formaldehyde reacts with gelatin to harden it, but formaldehyde will not react with most polymers.

    OTOH, a polymer is often resistant to yellowing. So, they might be usuable as an overcoat on a dry print to give it a 'wet' or glossy look. This is the method used in some spray on treatments for prints.

    I cannot comment on the utility of any particular polymer for potential use in or on a photographic material. I can just say try it and see. Many of these are rather hard to come by though, at least in their pure form.

    They are made by initiating a chain reaction in a solution of the monomer so a solution of the monomer called acrylamde can be polymerized into polyacrylamide which turns it from a thin organic liquid into a thick organic polymer akin to man made gelatin. (with the drawbacks above). Mixing acrylamide with other monomers and initiating that chain reaction can add hardenable sites to the polymer and make it more like gelatin.

    Too much chemistry, right? Lets forget it for now.

    Polymers can be good or bad. They have to be judged by trial and error for being useful in a photo material. You have to do the grunt work.

    Have fun.

    PE

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