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  1. #1

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    Disappointing results (i.e. nothing happened !)

    Hello Everyone, I just tried mixing (first time mixing anything from raw chemicals) the D-85 found on unblinkingeye.com. I followed the formula in the order shown, mixing each chemical in until fully dissolved. I also substituted the Paraformaldehyde for acetone.
    Nothing happened ! I left a test strip in the developer for 20mins, and nothing. I tried Ilford Multi FB paper (wasn't expecting it to work from what I read, but tried anyways) and Forte Poly warm tone FB (supposed to be lithable). I then left the test strips out (of the tray that is), with any developer left in it, over night. There has been a change in paper color (Forte is copper looking). Any ideas where I went wrong, and if I can add to or save the batch ?

    thanks
    steven


    D-85 Two Solution Lith Developer

    Solution A
    Water at 125° F 500 ml
    Sodium sulphite 36.5 g
    Boric acid crystals 9.4 g
    Hydroquinone 28 g
    Potassium bromide 2 g
    Water to make 1 litre

    Solution B

    Water at 90 ° F 500 ml
    Sodium bisulphite 11 g
    Sodium sulphite 1 g
    Paraformaldehyde 37.5 g
    Water to make 1 litre

    Mix solutions with good ventilation. Mix 4 parts A + 1 part B for use.
    You may substitute 82.5 millilitres of acetone for the paraformaldehyde.

  2. #2

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    The formula seems to be missing an alkali! Very strange. I checked unblinkingeye and digitaltruth, and they have the same formula. Try adding 10g sodium hydroxide or 30g sodium carbonate.

  3. #3

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    The paraformaldehyde reacts with the sodium sulfite to generate sodium hydroxide and the formaldehyde sulfur dioxide addition product.

    Na2SO3 + H2O + HCHO --> 2NaOH + HCHO.SO2

  4. #4

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    ... but if you're using acetone instead of formaldehyde, does the same thing happen?

    Edit: Indeed, it seems it should.

  5. #5

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    Yes. It is the carbonyl (-CO-) group in both acetone and formaldehyde which reacts.

  6. #6

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    It's great to have real chemists on the board! I'd still add some alkali to the mix to see what happens. When I've tried Ilford papers in my homemade lith developers, it's not that they don't develop, they pretty much turn grey-black all over, immediately. See the Dr. Jekyll formulas in the paper developer formulas section.

  7. #7
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    Quote Originally Posted by Gerald Koch
    Yes. It is the carbonyl (-CO-) group in both acetone and formaldehyde which reacts.
    While I agree with this statement, I question the rate at which it proceeds and the yield that it gives.

    If either rate or yield is off, you don't get the amount of base that you are entitled to.

    My question is this... Was part "B" cloudy? This is a characteristic of the reaction when the paraformaldehyde reaction does not take place or is slow or is incomplete. In that case, there was not enough base formed. If acetone was used, remaining acetone odor is the clue that things didn't work as expected.

    This is a neat way to get base, but I wouldn't do it myself for any reason other than avoiding handling sodium hydroxide. But then you are substituting formalin. Nice tradeoff.

    PE

  8. #8

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    The portraitist G. Paul Bishop used the following for all his negatives. Here the acetone serves only to create an alkaline solution by reacting with the sulfite.

    Water .................................. 28 oz
    Acetone ................................ 1 oz
    Sodium sulfite (anhy) .................. 30 gr
    Metol .................................. 20 gr

    http://www.gpaulbishop.com

  9. #9

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    Quote Originally Posted by Photo Engineer
    While I agree with this statement, I question the rate at which it proceeds and the yield that it gives.

    If either rate or yield is off, you don't get the amount of base that you are entitled to.

    My question is this... Was part "B" cloudy? This is a characteristic of the reaction when the paraformaldehyde reaction does not take place or is slow or is incomplete. In that case, there was not enough base formed. If acetone was used, remaining acetone odor is the clue that things didn't work as expected.

    This is a neat way to get base, but I wouldn't do it myself for any reason other than avoiding handling sodium hydroxide. But then you are substituting formalin. Nice tradeoff.

    PE
    Hi, yes part B is cloudy, and still has a strong acetone odor. Working solution is clearer, maybe just a tint of cloudiness, and has a much less pronouced acetone odor.
    Can I fix this, or is it just no good ? Also, was considering trying Ansco 81, but I can't find dilutions to use with paper developing.

    Many thanks for all the replies !
    Steven

  10. #10

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    The reaction between acetone or formaldehyde does not go to completion but is in equilibrium. The intent is to reduce the amount of sulfite ion in solution to a low level to encourage infectious development. As sulfite is used up more is released from the addition product. In other words the adduct is a reservoir for sulfite ion.

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