phenidone "spoilage"?

Discussion in 'B&W: Film, Paper, Chemistry' started by MikeSeb, Jun 14, 2008.

  1. MikeSeb

    MikeSeb Member

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    Does phenidone "go bad" on the shelf? I have kept mine in the same plastic bottle in which the Formulary shipped it to me. It is a bit caked--the stuff has the consistency of powdered sugar, tends to cling to itself as if slightly "greasy", and I think is a a very pale yellow (not in front of me at present.)

    Reason I ask--I had some problems (gross underdevelopment, no other obvious cause) with a recent batch of mytol, and wondered, of its components, which was the most likely to be at fault.

    I've tried making up a phenidone stock solution in 100mL of propylene glycol, but it did not dissolve welll. Now I have a waxy mess with a bit of PG left in the bottle, kinda like the comb in the jar of honey!

    Thanks all.
     
  2. Paul Verizzo

    Paul Verizzo Member

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    I can't tell you how old mine is, it's that old. Maybe twenty years? It's still relatively powdery and works fine.

    I'd do a CYA and get new stuff. Your description doesn't sound encouraging.
     
  3. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Doesn't it absorb moisture from the air? If it's been exposed to a lot of humidity, the weight could be off.

    I made some mytol that was weaker than expected, and I chalked it up to substituting ground vitamin C tablets of uncertain composition for sodium ascorbate.
     
  4. Paul Verizzo

    Paul Verizzo Member

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    But a good jar should keep that out. I'll grant you that most of my Phenidone's life was spent in dryer climes. Now I'm in FL, so I'll check in another ten years!
     
  5. Ian Grant

    Ian Grant Subscriber

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    My original batch of Phenidone lasted about 30 years, I bought it in the late 70's but the Ilford date code indicated it was manufactured in 1965. So it was over 40 years old when I finished it, it behaved no differently to the newer Phenidone I restocked with.

    Ian
     
  6. gainer

    gainer Subscriber

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    The vitamin C in tablets is usually ascorbic acid. That would make the Mytol weaker than expected. Try dissolving one in water with a little baking soda. If it fizzes, it's the acid.
     
  7. Murray Kelly

    Murray Kelly Member

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    I've got some phenidone here that still works OK. It's Ilford brand (?possibly Ph-S?) and I bought it in 1959.
    Murray