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Article: Instant MYTOL

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    Instant MYTOL

    Here's a formula that gives a developer with the same ascorbate and phenidone concentrations as MYTOL, has a similar sulfite concentration, and matches the pH of MYTOL's stock solution.

    It should be simpler to mix in that it doesn't use sodium metabisulfite and replaces sodium ascorbate with the more readily obtainable ascorbic acid. You should be able to use it as you would use MYTOL or XTOL.

    Start with 750 ml water
    60 g sodium sulfite (anhydrous)
    11.5 g ascorbic acid
    0.15 g phenidone (easier to handle as a stock solution in alcohol or glycol)
    13.4 ml triethanolamine OR 7 g sodium metaborate
    Water to 1 L

    Target pH of the stock solution is 8.2. Triethanolamine is a better buffer at this pH than borate, so the triethanolamine version is preferred. I'd appreciate comments on this formula.

    Edit: This formula can be mixed as an organic solution as well. Combine 13.4 ml triethanolamine and about 20 ml of propylene glycol and heat in a water bath or on a hot plate. Add 11.5 g ascorbic acid and 0.15 g phenidone and stir until dissolved (it could take quite a while -- magnetic stirring will help -- addition of 1-2 ml of water may also aid dissolution). Then dilute with propylene glycol to a final volume of 50 ml. This organic solution should keep almost indefinitely. To use, dilute 1+19 with water containing 60 g/L sodium sulfite.
    Last edited by Jordan; 12-11-2006 at 12:02 PM. Click to view previous post history.

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    An interesting formula, Jordan. I'll mix some and try it out.

    Seems to me that it should be possible to take the ascorbic acid and phenidone and dissolve them in the triethanolamine, then mix this solution together with some propylene glycol (say, enough P G to make a total solution volume of 100ml) this would make a long shelf life, low viscosity stock concentrate.

    The appropriate amounts of water and sodium sulfite could then be added to an appropriate amount of the stock concentrate make the working developer.
    Last edited by Tom Hoskinson; 11-16-2006 at 03:52 PM. Click to view previous post history. Reason: grammar
    Tom Hoskinson
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    Hi Tom -- I did consider the idea of mixing the AA and phenidone up in an organic solvent, a la Gainer, and actually tried it with propylene glycol. Unfortunately the solubility of ascorbic acid in propylene glycol doesn't seem to be high enough to make it worthwhile. PC-Glycol calls for 10 g AA in 100 ml of glycol -- this is close to what MYTOL requires in a litre of stock solution, and is near the solubility limit of AA in glycol. At most you could get a stock that would be diluted 1+9.

    Triethanolamine may work better for this purpose. The trick would be balancing the pH effect of the TEA with the amount needed to dissolve the AA at a worthwhile concentration. Cutting it with a bit of propylene glycol might do the job, but then you start getting into extra ingredients. Right now I'm content to handle just the phenidone as a stock solution in propylene glycol (20 mg/mL) -- it saves the hassle of accurately weighing sub-gram quantities of phenidone all the time.

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    I confirmed tonight that this formula works. I used the triethanolamine version and developed 35mm Fomapan 200 (Arista.EDU Ultra 200, exposed at EI 160 in my Yashica GSN) for 6 mins at 20C (the recommended time for stock XTOL). Continuous agitation for the first minute, four inversions per minute thereafter.

    The results are quite nice. There is a lot of shadow detail, but 6' may be a tad too long. The real proof of the pudding, of course, will be in the printing/scanning.

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    Quote Originally Posted by Jordan View Post
    I confirmed tonight that this formula works. I used the triethanolamine version and developed 35mm Fomapan 200 (Arista.EDU Ultra 200, exposed at EI 160 in my Yashica GSN) for 6 mins at 20C (the recommended time for stock XTOL). Continuous agitation for the first minute, four inversions per minute thereafter.

    The results are quite nice. There is a lot of shadow detail, but 6' may be a tad too long. The real proof of the pudding, of course, will be in the printing/scanning.
    Great Jordan, about 3 years ago in an Ascorbic Acid/Phenidone paper developer experiment, I found that I could dissolve a substantial amount of AA and Phenidone in Triethanolamine - then I reduced the viscosity of the mixture by adding Propylene Glycol to the mixture.

    This is analgous to what Pat Gainer did in the summer of 2006 when he collaborated with Sandy King on the Pyrocat-MC formulation. In that example, Pat dissolved Metol and Ascorbic Acid and a very small amount of water in a small amount of Triethanolamine. To this mixture, he added Propylene Glycol and Pyrocatechol. It worked very well.
    Tom Hoskinson
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    Tom -- I don't have too much TEA on hand to play around with, but if you do, go for it. The obvious solution (no pun intended) would be having the AA, phenidone and TEA in something like 50 ml propylene glycol, making it a stock for 1+19 dilution. I know that without the TEA, you can't dissolve ascorbic acid in propylene glycol at that high a concentration. If TEA helps the ascorbic acid (which I imagine it must), it could make for an interesting application.

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    Jordan, I have a gallon of TEA on hand - think I'll try it sometime next week.
    Tom Hoskinson
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    Thanks for posting this Jordan. It was what I was looking for with my Mytol Mixup thread (http://www.apug.org/forums/showthrea...ghlight=mytol). I haven't gone back to try Mytol again but I will now.
    Best regards,
    James

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    Right James, I remember that thread now. I guess I did go and do what I said I would Give this "Instant MYTOL" a try and let me know how it works for you. Once mixed, I don't think it'll have a fabulous shelf life, but it should at least be easy to mix one-shot.

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    It's possible to mix the triethanolamine, ascorbic acid, and phenidone together as an organic stock solution in propylene glycol. See my edit above.

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