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  1. #11

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    p.s. the Rain-X you need for the above trick is the one that makes the glass hydrophobic. The one that you use on the outside of the car.

  2. #12

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    This may be the magic ingredient in the American product "Rain-X Anti-Fog" or "Fog-X", a treatment that makes glass hydrophillic.
    I have tried this. Did not work.

  3. #13

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    Hans - can you recommend a source for the Silane? That's probably not going to be an easy one for most people to get ahold of.
    SigmaAldrich has it. I order mine here in Holland from a chemistry supplier that sells to schools and universities.

  4. #14
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    It is my experience that emulsion slips off the glass far more easily if a hardener has been added. For frill-free coatings: forgo hardeners, use Everclear as the only surfactant, and have very smooth edges on your plates. Clean the glass well and end with a rinse of half Everclear, half distilled water - all very simple with a minimum of toxic chemicals, time and expense.

  5. #15

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    Intersting Denise - with my limited plate pouring I had little frilling. I used chrome alum and I ground the edges of my plates.

    I know I've asked before, but were you using glyoxal or chrome alum for the hardener?

  6. #16

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    Hans - are you making holo plates for professional research or for fun? I guess I'm interested in your background...

  7. #17

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    Hans - are you making holo plates for professional research or for fun? I guess I'm interested in your background...
    At the moment just for fun.

  8. #18
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    Glyoxal allows more frilling and blistering on glass plates than chrome alum. Grinding the edges of your plates with a file or some emory paper to give a tiny rough edge will decrease frilling. You can use a mixture of chrome alum and glyoxal. Chrome alum is slower to harden than glyoxal. It is so slow, that you can find old formulas in which the emulsion was prepared for coating with the chrome alum and then stored for a few days in the cooler. This cannot be done with other hardeners.

    Both chrome alum and glyoxal decompose with keeping and lose activity. Both can react with some addenda in emulsions that decrease or increase activity, and both are sensitive to pH.

    PE

  9. #19
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    Kirk,

    I only use a hardener (glyoxal) when I'm doing emulsion transfers. The emulsion slips right off the substrate in a perfect, transferable sheet. I discovered this by way of my usual research s.o.p. I always start a new recipe with as few additional chemicals as possible, and then add one at a time to determine the pluses and minuses of each addition. My original dry plates without hardener were great, but due diligence had me try glyoxal. Voila! the emulsion transfer was born. But, since I rarely want an emulsion transfer, I never use hardeners in my dry plate recipes.

    Chrome alum was almost certainly added to the old dry plates to protect them against a range of water temperatures. Before refrigeration and air conditioning, photographers had a big problem during the summer months. Today, we don't need that insurance. Glyoxal is a great hardener for paper, but a dismal failure for plates. In addition, chrome-hardened plates should cure for up to a week. That is time I don't want to expend and in that time the chances of fogging go up. I recommend that you go without a hardener and watch your water temperature and plate handling protocol (don't manhandle the edges while the plates are wet.) K.I.S.S.

    One more tip: Emulsion will have a tendency to pull back from an edge defect on the glass. Raw snapped glass has a sharp edge that will cut the emulsion. It is important to smooth the edges of the plates before coating. This allows the emulsion to flow over the edges and dry without flaws that can break during development and allow the chemistry to work its way between the emulsion and glass (i.e. 'frilling').

    Hans,
    Welcome to APUG! I can hardly wait to see your holograms.

    Denise

  10. #20

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    Hi Everyone,
    Befor going out to buy exotic chemicals, read my article on Glass preparation on The Light Farm. Using this procedure, I NEVER see frilling or lifting of the emulsion from glass, hardener or none.
    I have been using amino-silane for adhesion to glass since 1974. We used to buy it by the 55 gallon drum. It works much better if you can incorperate it into the emulsion,rather than coat it directly onto the glass.
    A.freind of mine uses amino-silane to attache Carbon Tissue,which is gelatin based, to glass.
    Counter-intuitivly, his best results are obtained by applying 4 heavy coats of 5% amino-silane to glass and not polishing.
    I purchase my amino-silane from HIS Glassworks. They have a website and sell 5% amino -silane in "ultra-pure" IPA for $33.00/liter. It is important to keep the silane solution water free prior to coating.
    Regards,
    Bill

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