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Thread: XTOL patented?

  1. #11

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    Quote Originally Posted by Ian Grant View Post
    Yes there's a little man with a workshop converting Polaroid cameras for 5x4 use who claims to have a Patent

    Ian
    Really? Where? I want one.

  2. #12

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    Quote Originally Posted by cmo View Post
    There is even a commercial clone named Fomadon Excel.
    I have seen some reports that the Foma clone of Xtol has poor keeping and suffers from a sudden loss of activity. Xtol doesn`t suffer from that these days.

  3. #13
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    Quote Originally Posted by Keith Tapscott. View Post
    Really? Where? I want one.
    Ask a happy user like Brad Pitt

    At least it wasn't his money that was wasted . . . . . . . . ex wife's I believe.

    Ian

  4. #14
    cmo
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    Quote Originally Posted by gainer View Post
    There are times when it is better to keep a formula secret than to patent it, especially if the idea behind your patent is new.
    Diafine is probably a good example for that - as far as I know there is no patent, but nobody knows the formula.

  5. #15
    cmo
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    Quote Originally Posted by Keith Tapscott. View Post
    I have seen some reports that the Foma clone of Xtol has poor keeping and suffers from a sudden loss of activity. Xtol doesn`t suffer from that these days.
    There are many forum authors stating that they have seen some reports from people that have heard somewhere that there is a rumour about a man who said that all developers that are even similar to XTol suffer from a sudden loss of activity...and he knew exactly though he never used it

    I never used that Fomadon Excel, but it could be the same kind of "urban lab legends".

  6. #16

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    In the Film Developing Cookbook it is stated "A close approximation to the formula for Xtol is published in US Patent 5,756,271 (1998)."
    It takes a while to download but at this time it can be found via here:
    www.pat2pdf.org/patents/pat5756271.pdf
    My understanding is that so long as the formula of Xtol is within the specification of this (and possibly any other similar patent of Kodak) then nobody else is allowed to market an identical product.I am not saying that Kodak does change the formula of Xtol but the patent does not tie them down to making the exact same formula of Xtol at all times in the life of the patent.
    Last edited by Alan Johnson; 10-06-2009 at 10:36 AM. Click to view previous post history.

  7. #17
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    Because of the Prior existence of the Swedish Patent and the fact that most of the ingredients are fairly standard for B&W developers it's probably un-enforceable.

    After all Ilford easily got around the Patent covering HC110 when they designed Ilfotec HC & LC.

    Ian

  8. #18
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    Sometimes a patent is quite devious. For example, one of the key points of HC110 was the method of manufacturing which amounts to a chemical synthesis. They used the SO2 and HBr adducts of TEA to prepare the syrup. This makes it inconvenient for a competitor, as this was new technology at the time. The use of a pair of adducts was a rather new technology that may have barred its use to Ilford. IDK for sure. But then, OTOH, maybe Ilford has a license. It does happen.

    PE

  9. #19
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    Ilford used slightly different compounds to get around the Kodak HC110 Patent, it's been written about a few times, the differences are quite clear in the MSDS sheets, although it's thought there may be additional unlisted compounds to prevent dichroic fogging in Ilfotec HC.

    What it shows is it's relatively easy to compound a slightly different formula which has the same basic properties and can used a s a substitute for all practical purposes.

    Ian

  10. #20
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    Well, getting arount the patent did probably cost Ilford time and money. So, AFAIK or anyone knows, it did buy Kodak something for their efforts. OTOH, C-41 and E-6 were freebies for Agfa, Konica, Fuji and Ferrania. Kodak avoided the use of CD-6, which was in the works, just to avoid litigation and allow more free access. The Bleach design work was not free even though it was not patentable.

    PE

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