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  1. #31

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    Here might be a place to start... you will find tons of stuff in the patent literature.

    Just type the patent numbers in the quick search...

    http://patft.uspto.gov/netahtml/search-bool.html

    The following is from something I found on google just now....
    Further, various chemical sensitization methods which are commonly applied to usual emulsions, may be applied to the emulsions of the present invention. Namely, chemical sensitization agents, for instance, active gelatin; noble metal sensitizing agents such as a water-soluble gold salt, a water-soluble platinum salt, a water-soluble palladium salt, a water-soluble rhodium salt and a water-soluble iridium salt; sulfur sensitizing agents; selenium sensitizing agent; or reduction sensitizing agents such as polyamines and stannous chloride, may be used alone or in combination for the chemical sensitization. Further, the silver halide can optically be sensitized to have a desired wave length. There is no particular restriction to the method for optical sensitization of the emulsion of the present invention. For instance, optical sensitization agents, e.g. cyanine dyes or merocyanine dyes such as a zeromethine dye, a mono-methine dye, a dimethine dye, and trimethine dye, may be used alone or in combination (e.g. for super dye sensitization) for the optical sensitization. Techniques for such optical sensitization are also disclosed, for instance, in U.S. Pat. Nos. 2,688,545, 2,912,329, 3,397,060, 3,615,639, 3,397,060, 3,615,635, and 3,628,964, British Pat. Nos. 1,195,302, 1,242,588 and 1,293,862, German Patent (OLS) Nos. 20 30 326 and 21 21 780 and Japanese Patent Publication Nos. 4936/1968 and 14030/1969. The selection may be optionally made depending upon the particular application or purpose of the light-sensitive material, such as the desired wave length for sensitization, or the desired sensitivity........

    Sourcing speciality chemicals is a tricky business. If you follow the M&P forum you will see that a bunch of people bought a bunch of amidol really cheap from china. You can start with google.

    Feel free to contact me via private message, I used to work in the chemical industry and sourced stuff all the time.

    I would make film but I only have enough time for taking pictures.

  2. #32

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  3. #33

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    Thanks Aaron, I am glad all the info is out there, just a matter of wading through the theory...

  4. #34

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    The wiley book will help you the most. It tells you exactly what is used by the industry and also a chapter on manufacturers.
    Patent literature is much more vague, and unless you have a chemistry background, incomprehensable.

  5. #35

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    Quote Originally Posted by avandesande
    The wiley book will help you the most. It tells you exactly what is used by the industry and also a chapter on manufacturers.
    Patent literature is much more vague, and unless you have a chemistry background, incomprehensable.
    I might just get the book to keep just in case. It has been a looooong time since I did any organic chemistry and as you say what I saw of the patent lit was though reading..

  6. #36

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    LOL...well on second thought at $285 a pop I think the book is going to have to wait....

  7. #37
    Ian Grant's Avatar
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    Actually as someone who patented a photographic process / emulsion there is not much you can really do in practice as very small differances would get around it.

    For easons of commercial secrecy companies don't publish their formulae.

    The best (and only) source of good published emulsion formulae was made available after WW11 by the Allies when they translated all the Agfa Gevaert formulae. The books are quite difficult to get hold of, I employed a consultant in the 70's who happened to be related to the Lumiere family, (of Autochrome fame) and had acquired their copies.

    These books went into great detail of all the manufacturing and coating techniques, I copied what I needed at the time.

    Ian

    Quote Originally Posted by Dave Wooten
    1. Are the formulas protected by patent?

  8. #38

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    Quote Originally Posted by chuck94022
    Can film be produced with sufficiently affordable equipment
    that one could start with a small operation and then grow
    it over time if demand required? Where would one start?
    I think that world wide there must be scores of small
    producers, nitch producers, of silver gelatin films. IIRC, films
    for our purposes began to be manufactured and offered to the
    public around about the 1880s. Kodak then marketed their first
    send it all in the for processing and reload, camera and film.

    For starters do a search for historical information on the
    manufacture of film. Now, 125 years after those beginnings,
    much research has been done, much equipment invented,
    and much of that, I dare say, is available in today's form
    at huge discount. Now days there is no having to coal
    the boilers. A snap to do, don't you think? Dan

  9. #39
    Ian Grant's Avatar
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    If you had to you could try these for starters :-)

    1, 1'-diethylcarbocyanine chloride (was marketed as sensitol red in the 1930's)

    or 2-p-dimethylaminostyryl-pyridine methiodide

    Both found in 1930's publication and with referance to Eastman Kodak Research laboratories.

    Quote Originally Posted by Jorge
    Do you know where I can find this information? If you have checked it out, do you know if they are terribly expensive?

  10. #40
    fhovie's Avatar
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    apugpan -

    can be pushed 14 stops - can capture details on the sun and moon during a partial eclipse - 35mm version can be blown up to 48 x 60 INCHs without grain. Very high accutance. Good red sensitivity. Available in ALL formats from 16mm to 16x20.

    $1 per roll
    100 sht box of 8x10 - $25

    What do you think???
    My photos are always without all that distracting color ...

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