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  1. #21

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    Quote Originally Posted by Photo Engineer View Post
    I have several Defensive Publications and Research Disclosures on this. I cannot help you with the RDs and DPs, as they cost $$ to read and copy.
    PE
    How much do they actually cost?

    BTW, I checked Defensive Publications and what I saw there looked... misleading. Is the one you are thinking of related to linux?

    http://www.defensivepublications.org/login.jsp?se=true

    "Research Disclosures" is fairly well known, but have never tried to get a hold of one...how much does it cost to obtain them?

    Does anyone know if there has ever been a challenge to their right to qualify as "proper publication"? What is their circulation? IIRC not just any form of "publicaton" is suitable.
    Last edited by Ray Rogers; 02-21-2010 at 07:35 AM. Click to view previous post history.

  2. #22
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    Quote Originally Posted by thisismyname09 View Post
    I recall PE saying something about how the quality of gelatin that's available doesn't allow for fast film speeds. A few weeks ago I remember remembering this and thinking, "well then, why not use something other than gelatin?" Good to know that someone with the ability and knowledge to use that idea thought of it first. Fantastic stuff.

    You mentioned that this emulsion was coated on glass plates. Is it possible to coat the same stuff onto a film base or instead?
    This is a misquote. Today's gelatins do allow for high film speed, but you must choose the right gelatin and add the Sulfur and Gold in the right proportions and in a separate step. In the early days of emulsion making, the sulfur was present as an impurity in gelatin and gave the speed in one concerted operation but today it is controlled and done in a separate operation.

    The gelatin from the Photographers Formulary is a very highly purified bone gelatin made by Eastman Kodak for emulsion making. Other fine gelatins come from Rousselot in France and the Gelita division of Kind and Knox in the US.

    PE

  3. #23
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    Quote Originally Posted by Ray Rogers View Post
    How much do they actually cost?

    BTW, I checked Defensive Publications and what I saw there looked... misleading. Is the one you are thinking of related to linux?

    http://www.defensivepublications.org/login.jsp?se=true

    "Research Disclosures" is fairly well known, but have never tried to get a hold of one...how much does it cost to obtain them?

    Does anyone know if there has ever been a challenge to their right to qualify as "proper publication"? What is their circulation? IIRC not just any form of "publicaton" is suitable.

    Ray;

    I am not in a position to judge the merits of Research Disclosures. I know that they are an organization that will publish Research and allow others to obtain copies of the publication for a fee. Kodak used their service for years, and in several my co-inventors and I have disclosed polymeric peptizing agents and vehicles.

    Defensive publications are issued by the US Patent Office. They are very difficult to obtain. They are noted by having a "T" in front of their name (IIRC). The RDs are hard to get at and you are charged, the DPs are almost impossible to find on the Patent Office web site, but they do refer to them in the advanced search.

    I have no idea as to cost, as I have no interest in getting personal copies of my own work and paying for it. Sorry.

    What comes to mind is the Silver Behenate thermally processed material that was offered by EK several years back. The emulsion was coated from an organic solvent using a synthetic polymer base. It was not hardened AFAIK as it never was wet processed but rather was heat processed.

    PE

  4. #24

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    Quote Originally Posted by Photo Engineer View Post
    Ray;

    I am not in a position to judge the merits of Research Disclosures. I know that they are an organization that will publish Research and allow others to obtain copies of the publication for a fee. Defensive publications are issued by the US Patent Office. They are very difficult to obtain. The RDs are hard to get at and you are charged....
    PE
    Thanks...

    I should try to get one just to see what it takes.

  5. #25

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    Hi AgX;Ray and thisismyname09,
    ...09,
    I have not tried this emulsion on film. Most of my love of photography is intimately tied to glass. I will leave the film to those who are more interested in it. But I will get around to doing a few tests, just for info.
    Ray and AgX,
    My answere to AgX's question and to Ray's very valid points are very subjective. There probably is no great advantage to substituting synthetics for gelatin (unless you are a cow or pig). I like to know what I am working with, and my inquiries into the nature of gelatin have not satisfied my curiosity. If anyone has any refferences which adress, in a definative manner, the nature of gelatin, I am currious.
    Why did I start this thread? Simply because I wanted people to know what I have been doing for all this time. There is no "Great Grand Plan". The reason that my "Gelatin Subsitute" is covered by a CA is that it is usefull for processes much less complex than emulsion making.
    Ray, of course we are "still friends". Actualy, I am surprised that something like your post did not appear within an hour of my starting this thread.
    Cheers,
    Bill

  6. #26

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    Quote Originally Posted by wildbillbugman View Post
    Ray, of course we are "still friends". Bill
    Good.
    One can never be too careful....

    Anyway, now we get into the fun stuff!

    What role does the Glyoxal play? Is it to harden, or maintain the semipermeable gel state?

    If you actually have a gel state... is it more like syrup than a gel?

    How long after prep. can you process the plates? (is there a known window, or does the surface remain permeable to water forever... will it dissolve away without the glyoxal?)

    I think I am familiar with the observation you made about sensitization of such emulsions...
    it has been observed before.

    Unfortunately, I know more about gelatin than any good vegetarian ought to....
    I should be ashamed!

    You mentioned you hope "they" will manufacture it... is that part of the process difficult or time consuming?

    Looking forward to those pictures you promised!
    Last edited by Ray Rogers; 02-21-2010 at 06:51 PM. Click to view previous post history.

  7. #27
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    Hi Bill, labs are using inkjet printers now to 'spray' fine even coats of living cells and other materials such as solar cell components. With gelatin out of the equation do you think inkjet technology could be used with your formula to make precision coatings? People shouldn't think in terms of the emulsion having an inkjet pattern, since it is liquid it would settle and become uniform after the spraying. If so this could be a huge breakthrough in small scale production..

  8. #28

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    I have been thinking of inkjet coating for some time now.

    I have several hopelessly plugged up printers just waiting for such a project. In fact the endless problems with inkjet printers is what made me search for 'alternative' methods. Quite happy about that actually. :-)

  9. #29

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    What role does the Glyoxal play? Is it to harden, or maintain the semipermeable gel state?
    ------------------------------------------------------------------
    The Glyoxal hastens drying. It also improves adhesion to glass. It is not 100% required. An unhardened coating is functional. Actualy, Formalin works better for this. But my sinuses and eyeballs started protesting about Formalin.
    ----------------------------------------------------------------------

    If you actually have a gel state... is it more like syrup than a gel?
    ---------------------------------------------------------------
    The "gelatin substitute" is syrupy. It will not set-up. However, after adition of AgNO3 solution the look and "feel" of the emulsion is virtualy the same as a gelatin emulsion.
    -------------------------------------------------------------------------


    How long after prep. can you process the plates? (is there a known window, or does the surface remain permeable to water forever... will it dissolve away without the glyoxal?)
    ------------------------------------------------------------------
    While I have not done a formal, deliberate study. The emulsion still "works" after days of sitting at room temperature. I have exposed and developed plates 3 days after coating.
    ------------------------------------------------------------------

    I think I am familiar with the observation you made about sensitization of such emulsions...
    it has been observed before.
    ---------------------------------------------------------------------
    Thanks for the validization.
    -----------------------------------------------------------------
    Unfortunately, I know more about gelatin than any good vegetarian ought to....
    I should be ashamed!
    ---------------------------------------------------------------------
    I am ashamed (of myself). But I will not be mixing the "gelatin substitute"
    with sugar,coloring and flavoring to be consumed by me or anyone else.

    --------------------------------------------------------------------
    You mentioned you hope "they" will manufacture it... is that part of the process difficult or time consuming?
    -----------------------------------------------------------------------
    The making of the "gelatin substitute" Is time consuming and labor intensive. But it is not "rocket science".
    I don`t think many people would want to make it at home. ----------------------------------------------------------------

    Looking forward to those pictures you promised![/QUOTE]
    ---------------------------------------------------------------
    I had other mundane stuff to do. Hopefuly will coat tonight.
    -------------------------------------------------------------
    Bill

  10. #30

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    Bill,

    (Thanks- Just a few more questions before I have to go and do those other mundane chores myself!)

    What volume of ready to coat emulsion does one mole silver nitrate make, when made according your procedure?

    You said the Glyoxal aids drying...how long does it take to dry without the glyoxal?

    I am sure there are many who would like to try it... but waaaaaiiiiitinnngg is not everyone's strong point.

    Wouldn't it be possible for your seller to just purchase the gel substitute and
    resell it, rather than make it themselves?

    That would make it avail much sooner I would think....



 

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