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  1. #1

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    TEA is a slow destroyer? (yellow and red)

    I mixed up some Instant Mytol in organic solvents (TEA and PG) a couple of months ago. Here is the posting for it. Here's what it looks like now:

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    It's turned yellow, with a red haze along the top. Red! I noticed this after 7 weeks, but I hadn't been looking before that. This concentrate has been in a stoppered glass bottle the entire time. I also have some concentrate that's two weeks old of a different formula that contains no TEA, and it's still clear. The other ingredients are the same, making me wonder if TEA is destroying something else in the brew.

    Any idea what's happening?

    Mark Overton

  2. #2

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    It looks like oxidation to me. When you say stoppered do you mean you are not using a screw cap? I can't tell from the picture.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  3. #3

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    Quote Originally Posted by Gerald C Koch View Post
    It looks like oxidation to me. When you say stoppered do you mean you are not using a screw cap? I can't tell from the picture.
    I meant a screw cap. This is an amber bottle sold by the Formulary, the kind that has a built-in dropper. The cap has a rubber seal.

    Mark Overton

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    TEA being alkaline will hasten oxidation. However it looks worse than it actually is because the oxidation products are dark in color. Once the oxygen at the top of the bottle is exhausted it will stop. I doubt you will find any noticeable change in activity.

    I would not use a cap with a dropper as it may leak air into the bottle more easily that a regular cap.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  5. #5

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    Quote Originally Posted by Gerald C Koch View Post
    TEA being alkaline will hasten oxidation.
    I haven't read any reports of problems like this from users of PC-TEA, so mixing P&C into TEA seems okay. What Instant Mytol adds is propylene glycol. It makes me wonder if TEA and PG don't get along (at least when used with P&C).

    Your improved PC-TEA formula which you posted long ago to the pure-silver list used TEA+PG+vitaminC+dimezoneS. Do you recall any long-term storage issues with it?

    Mark Overton

  6. #6

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    Quote Originally Posted by albada View Post
    I haven't read any reports of problems like this from users of PC-TEA, so mixing P&C into TEA seems okay. What Instant Mytol adds is propylene glycol. It makes me wonder if TEA and PG don't get along (at least when used with P&C).

    Your improved PC-TEA formula which you posted long ago to the pure-silver list used TEA+PG+vitaminC+dimezoneS. Do you recall any long-term storage issues with it?

    Mark Overton
    The reason for using the PG and TEA mix was to avoid adding the developing agents to hot TEA which caused some initial rapid oxidation. By first dissolving them in PG and allowing the solution to cool before adding the TEA I found that the color of the concentrate was less than when the developing agents were added to the hot TEA. This concentrate also darkened less with age. Darkening indicates oxidation.

    As an added bonus using a PG+TEA mix allows you some adjustment the pH of the working strength developer.

    Agfa Studional (Rodinal Special) uses a high concentration of TEA (approximately 40% of the concentrate) and has a long shelf life. I would conclude from this that TEA has no special adverse effect of developers. All alkalies will hasten the oxidation of the developing agents but TEA seems no worse than say sodium carbonate or other common alkalies.

    It is best to avoid overheating the PG when adding the developing agents as this also accelerates initial oxidation. I put the Dimezone and ascorbic acid into room temperature PG in appropriate size glass bottle and cap it. They will eventually dissolve with shaking at room temperature if one is patient, You can put the bottle in a warm water bath and periodically crack the cap to allow air to escape. When everything is dissolved then add the TEA to the bottle and mix.

    There will always be a problem with ascorbic acid as it is more susceptable to oxidation than other common developing agents. I have had a bottle go dark brown in less than a year while I have some hydroquinone that is 25 years old which shows no discoloration.
    Last edited by Gerald C Koch; 01-29-2012 at 07:52 AM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  7. #7
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    I remember reading a thread on pyro510 where Jay Defehr mentioned that some forms of TEA had more water than others. When there was a higher amounts of water it promoted early oxidation.

  8. #8
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    Tea is a slow poison, if you drink enough of it over your lifetime, but you would need to live to around be150 for it to actually kill you .
    Ben

  9. #9
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    I found the Jay Defehr reference in the large format photog board......

    "Wait, 85% TEA? Don't use 85% TEA, it contains 15% water, and will activate the TEA as a base, and oxidize your concentrate. If you have to use it, dry it in a shallow glass dish in your oven at 250F to evaporate as much of the water as possible. If you've already added your chemicals, it's too late. Never use 85% TEA for developer concentrates."

    "http://www.chemistrystore.com/Chemicals_S_Z-Triethanolamine.html

    this is TEA 99%."

  10. #10

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    Quote Originally Posted by mrred View Post
    I found the Jay Defehr reference in the large format photog board......

    "Wait, 85% TEA? Don't use 85% TEA, it contains 15% water, and will activate the TEA as a base, and oxidize your concentrate. If you have to use it, dry it in a shallow glass dish in your oven at 250F to evaporate as much of the water as possible. If you've already added your chemicals, it's too late. Never use 85% TEA for developer concentrates."

    "http://www.chemistrystore.com/Chemicals_S_Z-Triethanolamine.html

    this is TEA 99%."
    Quick note: That link to chemistrystore is 404. They probably shuffled their site around. Anyway...

    I bought my TEA from Photographer's Formulary (photoformulary.com), and I just now looked up their MSDS for the TEA they sell. Here it is: http://stores.photoformulary.com/ima...ine%20Msds.pdf
    Surprise! The stuff is 85%! This could explain the troubles I'm having with TEA. Thanks for pointing this out!

    Mark Overton

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