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  1. #1

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    ILFOCHROME HOME-BREWED BLEACH

    I’m a newbie on this site, but I’ve followed most of the threads on the dye bleach process for a while. As an organic chemist, I actually view the color darkroom as a laboratory, which can give me an artistic-emotional rush after each “experiment”. I think we are all aware of the convoluted, frustrating mess that Ilfochrome marketing has been over the last few years. We also know that the bleach step, and its precise chemistry has been shrouded in mystery for years. It is also obvious that it is this chemistry that provides all of the value-added for the process…and it is what you are actually paying for, big time. Currently, B&H is backordered on the P30 kits, while Freestyle can still drop-ship….with a $40 ship and hazmat fee added on top of the $100 for just two liters.

    So, I have now come up with a chemical synthesis of the active dye-bleach catalyst used in all modern formulae….Quinoxaline 7K (see all online MSDS’s for bleach components).

    I have also used e-bay extensively to buy “old” P30 kits, although exact ages cannot be determined. Without exception, part A of the bleach exhibits dramtatic decomposition wherein the solution turns dark greenish brown, while dark flock or tar separates. This problem is due to acid-induced decomposition of the active dye bleach catalyst. Additionally, the acid itself, in liquid formulation, is perhaps the main reason for the shipping restrictions. Chemically, you would have to be an idiot to formulate the kit in this manner, unless you desired planned obsolescence in time. To be fair, the larger volume (P3.20) and other roller transport formulations do not use this approach…. But, the acid used does indeed change to the cheaper sulfuric acid. So with the P30 kit formulation, only the little guy will have to worry about how long the item has been on the shelf.

    My approach is to use standard battery acid as the basis for a formulation. This is available locally, and over the counter and in convenient volumes at auto parts stores. In addition it is advisable in my mind to attempt to create more dilute bleach solutions which are safer and greener. However in this case, the process flow must be modified to include a bleach-fix step. Process time does not matter to me. My experimentation so far has been limited, and has been done only with outdated CLM.1K on the RC, non-deluxe, base.

    If you were able to gain access to the catalyst and the contrast control agent for Ilfochrome, you would also need to be able to answer, in the affirmative, the following questions:

    1) Can you mix a B&W low-contrast DIVIDED developer system as has often been described?
    2) Do you routinely use RA-4 blix (or Ferricyanide and non-hardening liquid fix conc.)?
    3) Can you locally purchase specific gravity 1.265 sulfuric acid for batteries?
    4) Can you easily go on e-bay to obtain a few additional, moderately-priced components?
    5) Do you have the ability to store used part-B of the divided developer to neutralize bleach?
    6) Have you got odds and ends around the house such as NaOH and non-natural vitamin C?

    I would like to gage the level of interest that other artist-craftsmen-teckies might have in attempting to formulate home-brewed Ilfochrome solutions. Respond to the post if you are desirous of pursuing such a project. I will respond back occasionally over the next few weeks, waiting to accumulate a list of candidates. Remember however that I can't give you anything on a silver platter....work and patience will still be required.

  2. #2
    tiberiustibz's Avatar
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    Sounds like an awesome way to waste time. I'm in! The ilfochrome process includes a standard B+w developer, a dye bleach, and a regular fix right? So I just need to make a dye bleach and mix/obtain a developer with similar characteristics... How much would variances in the dye bleach effect the image characteristics?
    --Nicholas Andre

  3. #3
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    Ilfochrome materials are much too expensive to play with for experimentation. You have to get it right quickly or you are into a lot of waste paper. The dye bleach process is just as prone to variations in balance and having crossover as any other color process, but has the additional burden of using a lot of acid.

    Well, that and the fact that KI is not all that nice at that pH either.

    I have lists of possible dye bleach formulas and catalysts here from our R&D on it at EK.

    PE

  4. #4
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    I'm very interested and like to experiment, but I have not much money to spend on paper. However, if there is some way we Apuggers can help, I'm in.

  5. #5
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    So the idea is to bypass Ilford and make home brew ??
    How long before Ilford gets pissed and one raises the price of paper to compensate for loss of chemical sales?
    Who will one point fingers at if the home hobbyist can not mix right?

  6. #6

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    At the moment I'm without a darkroom but give me six months and hopefully that will change. I have in the past used standard Beers B&W developer (+thiosulphate I think) and exposure adjustment as a way of tweaking contrast and it worked quite well. The fix was standard rapid fix. The bleach used was the P3 bleach which I used to be able to buy separately (albeit as three 2 litre bottles). The bleach step went to completion so wasn't significantly fussy about time so long as you gave it enough. I'm no longer sure about the availability of the separate bleach component plus it was hideously expensive here although the paper was still the main cost. If I'd have to buy the kits just to get the bleach (although I'd also use the fix) I'd certainly be interested in a home brew alternative. I have some old paper in the freezer but as mentioned I'll not be able to do anything for about six months by which time hopefully the new house will be finished and I'll have had a chance to put together the darkroom.

  7. #7
    hrst's Avatar
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    Quote Originally Posted by Bob Carnie View Post
    So the idea is to bypass Ilford and make home brew ??
    How long before Ilford gets pissed and one raises the price of paper to compensate for loss of chemical sales?
    The prices of Ilfochrome materials are unbelievably high already. There is a small, loyal group of customers who buy the products to make gallery prints, but it's very possible that Ilfochrome is dying soon as it is quite unusable for normal printing due to its price.

    Probably any attempt to make it possible to use this fine process will increase their paper sales.

    Quote Originally Posted by Bob Carnie View Post
    Who will one point fingers at if the home hobbyist can not mix right?
    Ummmmmmm...???? Maybe you can point your finger at yourself if you do something by yourself, for yourself?

  8. #8
    tiberiustibz's Avatar
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    I forgot to mention that I'm a poor schoolchild. I have hydroquinone, metol, sodium sulphite, borax, sodium metaborate, and probably one or two others im forgetting as well as enough C41 chemistry to open a small lab.
    --Nicholas Andre

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    Well, I'm glad the dichotomy of whether such an undertaking would be good or bad for Ilford(Oji) has come out so soon. I find it hard to believe that a few lone experimenters could in any way alter the longevity of Ilfochrome in the marketplace. Forces larger than ourselves will determine that. But in the meantime, I just like to play...and as in any lottery, if you don't play, you can't win. The following is a link which describes a typical divided(part A with developing agents, and part B with activating alkali)developer:

    http://www.photography-forums.com/ga...-t92014p2.html

    Nicholas....You have almost everything you need already with the exception of a little potassium bromide!
    Try a google search for "divided developer" to find more.

    PE....I use only 15 ml. battery acid per liter, along with a little bisulfate. The P30 kit uses a total of 80 grams of organic and inorganic acids and more than twice the amount of silver ligand. I would love it you could dig out some your formulas! I know that you have been partial to phenazines on this site in the past. In my patent collection, the most commonly used phenazine is 2,3-diaminophenazine, which unfortunately is a suspected carcinogen. The quinoxalines are devoid of this problem.

  10. #10
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    Both phenazines and quinoxalines are used in DB solutions. I have some patents here, but they are not in my usual repertoire. Kodak and Ilford have many patents on the subject. There are other classes of catalysts as well. In my research disclosure (Haist, King and Mowrey) you will see that no catalyst was used. Actually, one of the developing agents acted as an electron transport and did it as well or better than anything else. And, it was low in toxicity.

    PE

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