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  1. #21

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    Quote Originally Posted by Photo Engineer View Post
    That fixer contains Triethanol amine. As with any organic solvent, please be sure to wear rubber gloves when using it and during the early stages of the wash cycle. This is true of developers containing TEA as well.

    PE
    PE, What is the basis for your statement: "That fixer contains Triethanol amine." ?

    The Clear Fix MSDS does not listTriethanolamine, it lists Ammonium Thiosulfate (60%) and Sodium Sulfite.

    The Clear Wash MSDS lists Triethanolamine, Potassium Sulfite and Citric Acid.

    http://www.digitaltruth.com/msds/CLE...ALINE_MSDS.pdf
    Tom Hoskinson
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  2. #22
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    My bottle of Clearfix lists triethanol amine.

    PE

  3. #23

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    Quote Originally Posted by Photo Engineer View Post
    My bottle of Clearfix lists triethanol amine.

    PE
    Thanks, PE!
    Tom Hoskinson
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  4. #24
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    First, let me apologize for not responding earlier, but I was unaware of this thread until Tom brought it to my attention.

    I have to say a few things here. Anyone reading this discussion should be aware that there are some participants with a potential vested interest in both Clearfix and TF-4, including myself. At Digitaltruth Photo we sell both fixers, although Clearfix Alkaline is our own product. Bill Troop (who formulated TF-4) is a friend of mine, and I also have a working relationship with Bud at Photographers' Formulary, so I have no desire to make any negative statements about TF-4. In fact, I agree with Ron that TF-4 is a proven and trusted formula, and certainly recommend that TF-4 users who are happy with the product continue to use it. TF-4 has a good track record, and although it may seem like an obvious point, I do not think that environmental-friendliness was part of its design goal.

    Clearfix Alkaline was developed by Ryuji Suzuki specifically to improve upon other existing fixers. I am not in possession of the formula for TF-4, but as Ron has pointed out and as I'm sure Bill would be the first to admit, the cloudy appearance is due to a large amount of buffering agent (presumed to be borax). Clearfix Alkaline is entirely free of borates. It is clear and goes into solution easily because it uses a very advanced buffering system. We developed this product in an effort to create the best alkaline fixer on the market. Whether we have succeeded is up to individuals to decide for themselves.

    I cannot comment on how well the buffering system in TF-4 handles acid stop bath, but the official documentation recommends a water rinse prior to immersion in the stop. No such rinse is required with Clearfix, which can easily handle any carry-over acid from a stop bath.

    With regard to the compounds used in Clearfix Alkaline, all ingredients over 2% are listed on the MSDS, as is standard practice. Furthermore, we have listed triethanolamine on the bottle as a small amount is present in the solution. Naturally, we want to provide full disclosure of any potentially harmful ingredients, regardless of how low-risk or how small the quantities actually are. Although the design goal of Silvergrain chemistry is to be as low in toxicity as possible, we provide full warnings and certainly make no claims that the products have no toxicity whatsoever. Our contention is that Silvergrain products are the least toxic commercially produced chemicals currently manufactured. To back this up we have produced extensive information which is available on this page:

    http://www.digitaltruth.com/store/si...ixandwash.html

    The bottom line is that all modern rapid fixers consist mainly of ammonium thiosulfate. As Lowell Huff likes to tell me, the main difference between fixers is the label on the bottle. While that is undoubtedly true, I'd like to think that in the case of Clearfix Alkaline we have produced a product that puts a lie to this statement. As with any science, the research carried out by Ryuji Suzuki builds on the earlier work of Grant Haist and Bill Troop. Any capable person can test Clearfix Alkaline to determine its efficacy, and I'm sure you will find that it performs over and above the published specifications.

    I feel it is important in a public forum that genuine independent discussion takes place, so as I cannot be impartial I would prefer to answer any questions which aren't about the use of the product by email or private message. Questions about usage I'm happy to answer all day, and I'd be delighted to see more independent feedback posted here.
    --Jon Mided

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    http://www.digitaltruth.com

  5. #25

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    Quote Originally Posted by Digitaltruth View Post
    ... TF-4 ... the official documentation recommends
    a water rinse prior to immersion in the stop.
    No such rinse is required with Clearfix, which can easily
    handle any carry-over acid from a stop bath.
    "... a water rinse PRIOR to immersion in the stop."
    Well, that wouldn't bother Eddie Ephraums. But the
    second sentance above makes no sense of the
    first sentance. Dan

  6. #26
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    Sorry for the confused explanation. Here is the official correction:

    TF-4 instructions state that you should use a short water rinse AFTER the stop bath and before the fix. The purpose of this rinse is to remove acid being carried over into the fixer from the stop bath.

    Clearfix Alkaline does not require any such intermediate rinse, as the buffering system can handle the acid carryover.
    --Jon Mided

    Digitaltruth Photo
    http://www.digitaltruth.com

  7. #27
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    Jon;

    I have no doubt that your fixer is a good fixer. I made a statement about the first documented use of TEA in a fix and its relationship to image stability which is certainly a potential new factor. I have also warned those who love to take prints out of the fixer with their hands, that this is no ordinary fixer due to containing an organic solvent and alkali like TEA. It is prudent to use tongs or rubber gloves. It should be treated more like a developer in that regard.

    I would like to add for the record that I have no vested interest in TF-4 fix in any way whatsoever. The only fix formula of mine currently available is my Super Fix formula which has been donated to the public both here and on Photo Net. I have no fix being produced commercially, nor any about to be sold.

    Grant Haist also has no commercial enterprises at this time AFAIK, except for his book. He is the ultimate source of some of this information, as is my own research work on bleaches and fixes at Eastman Kodak. Bill Troop's interest in TF-4 is well known.

    During design work at EK, both Grant and I remember that it was suggested that we avoid TEA in fixers. I don't remember the reason, and neither does Grant, but he remembers it came from Eaton as I said above. Kodak sold several alkaline fixers and they were all buffered with carbonate or borate. These fixers were initially designed by Eaton and Edens IIRC.

    PE

  8. #28
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    Quote Originally Posted by Digitaltruth View Post
    Questions about usage I'm happy to answer all day, and I'd be delighted to see more independent feedback posted here.
    I recently started using both TF-4 and Clearfix. I came upon the Clearfix from an offer from Silvergrain to try a free bottle. (Thank you Jon.) Previously, I had used Ilford Rapid Fix for several years.

    I don't have any chemical testing equipment other than some silver nitrate to test for residual hypo. Both TF-4 and Clearfix are giving me slightly better residual hypo results than Ilford Rapid Fix, all other things being kept the same such as wash time and hypo clearing treatment.

    This is not to say that Ilford is not a good fixer. It works very well. Using it on double-weight fiber paper, my residual hypo test would show just a very slight stain. Using TF-4 or Clearfix, I get no stain. This means I may be able to reduce my washing time a bit.

    The other marketed advantage of TF-4 is that it requires no hypo clearing treatment. This is not a big deal to me as it only saves 10 minutes or so of processing time. I'm still not fully convinced that a hypo clearing treatment is not necessary. Someone will have to provide some technical evidence that I cannot attain before I completely buy off on that idea.

    I have not tried using TF-4 going straight from the acid stop bath to the fixer. I've been squeemish about that because of the product's use instructions, but based on the comments in this thread, I'll give it a try.

    I cannot see any visual difference in my prints between using the three fixers. Either of the three is good to use IMO. I suppose trying to decide which one is best to use is like trying to decide on developers; it gets to be pretty subjective.
    Semper Fi & God Bless America
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  9. #29
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    I would like to comment further on image stability as it relates to fixers.

    I have found that the tests for retained hypo and retained silver can be interfered with by other ingredients in the fix. In testing the SuperFix with thiocyanate and thiourea, both ingredients can give different readings than with plain hypo due to having different complexation constants with silver. Not better or worse, just different. It becomes harder to evaluate the level of retained fixer or retained silver with different (new) ingredients in the fix. It therefore becomes more difficult to judge the effects of wash time.

    Testing the SuperFix with iodide for exhaustion also behaves differently than a plain hypo fix.

    Also, since fixes and wash aids are the last steps in the process, they have been shown to influence image stability. For example, varying amounts of retained hypo influence image stability. Too little makes it worse, just enough makes it better, and too much makes it worse (cf Ctein). Use of thiocyanate (Agfa Sistan) makes it slightly better.

    Therefore, when a fix or wash aid contains a new ingredient, the question immediately comes to my mind, "What did the image stability tests look like?".

    This was my fundamental question, and I come back to the thiourea and thiocyanate in the SuperFix. They are known to improve image stability so no harm should accrue from their use. Even so, I plan on doing image stability tests with it to insure that fact. But, at the same time, having had years of experience with both of them in fixes, I feel comfortable with their use in the SuperFix.

    TEA in a fix or post fix wash aid is entirely new as noted above.

    That is the basis of my question. If I were to design a fix for sale, I would run image stability tests. Were they run with these new products? IDK, I just ask the question.

    In a side note to Alex and others, TF-4 is highly buffered, and in my tests worked very well when used with a stop bath. Clayton fixers (concentrate in unopened bottles) don't have a very robust shelf life. Kodak fixer and TF-4 have similar shelf lives in the concentrate with TF-4 better, mixed, TF-4 lasts a bit longer as well. This is a pH effect that is well known. The hypo decomposes more rapidly at lower pH.

    PE

  10. #30

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    For example, varying amounts of retained hypo influence image stability. Too little makes it worse, just enough makes it better, and too much makes it worse (cf Ctein). Use of thiocyanate (Agfa Sistan) makes it slightly better.
    I haphazardly washing my film and paper, often leaving it under running water for longer than the recommended wash time, but never shorter. Is this a bad idea?

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