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Time to Stockpile Chemicals
I've amassed quite a lot of film including over 10,000 feet of ECN-2 stocks (1800 36 exp rolls approx). Now I'm worried that photo chemicals will become unavailable before I can develop it all, so I want to stockpile key chemicals -- CD3, CD4, maybe metol , hydroquinone, potassium bromide, benzotriazole, hydroxylamine sulfate, potassium ferricyanide, ferric ammonium EDTA- before they become unavailable or are banned by the enviro police.
My question relates mainly to the color developing agents. Most of the chemicals will keep a long time but the developing agents - especially the color ones - can deteriorate. I have some CD4 that I bought in 1987; it's still useable but is discolored and has lost some strength - maybe 10% or so.
My question to the knowledgeable is: Can such chemicals be frozen, and would that extend longevity? If so, should I add a small dessicant pack to each bottle before freezing?
Finally - anyone know where I can get CD3 and CD4 in larger quantities than 100g or 1/2 LB? I'd like to end up with about 2KG of each of CD3 and CD4.
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Most of the chemicals you mention are used for many other purposes other than photography. Their availablity is NOT going to change. As far as the color developing agents are concerned they do not keep well and should not be bought in large amounts. Don't panic!
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
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All dry, crystalline chemicals can be frozen AFAIK. Stock solutions should not be frozen, nor should concentrates.
Chemical prices will go up, as the common use of many of these was photography and as use declines price goes up.
PE
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Yes PE, they are all dry chemicals except the EDTA can no longer be obtained dry as far as I know. The ones I listed are, I believe, used mainly/only for photography and I am guessing will be extremely expensive in year or two. As for Gerald's comment re: color developing agents' keeping properties, I have to disagree where dry chemicals are concerned: As I indicated I have some 25-yr-old CD4 and I would definitely use it if I had nothing fresher - the only thing holding me back is I would need to develop a couple of test rolls to establish how much I may have to compensate for its age. I used it a year ago with no compensation and got pretty good negatives - maybe slightly underdeveloped, but I never did any testing to quantify. I'd probably add 10%. Twenty five years is probably all I have left!
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Hi Ron
For C41 and RA4 developers is there a shelf life that one should be aware of? I just spoke to someone who should know and he
stated 10 month timeline.
If this is true, how would one stockpile these chemicals with frozen paper?
FWIW I was thinking of purchasing a stock of C41 chemicals and colour negative film , and was thinking that enough for 5-8 years of imaging and processing.
If what this person says is true , how would I be able to develop the film into the future ?
thanks
Bob
 Originally Posted by Photo Engineer
All dry, crystalline chemicals can be frozen AFAIK. Stock solutions should not be frozen, nor should concentrates.
Chemical prices will go up, as the common use of many of these was photography and as use declines price goes up.
PE
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I buy dry powder raw chemicals and mix my own formulae - these chemicals last unmixed almost indefinitely. Ten months may be for the liquid components of pre-mixed chemistry. I'm still using some chemicals that are 25yrs old - potassium bromide, metol, hydroquinone, etc. It's these basic dry components that I want to stock up on.
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I am specifically questioning colour C41 and RA4 chemicals.. is this what you are referring too?
 Originally Posted by newcan1
I buy dry powder raw chemicals and mix my own formulae - these chemicals last unmixed almost indefinitely. Ten months may be for the liquid components of pre-mixed chemistry. I'm still using some chemicals that are 25yrs old - potassium bromide, metol, hydroquinone, etc. It's these basic dry components that I want to stock up on.
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C41 and RA4 chemistry, made up as concentrates, does not keep beyond a certain limit. I have not measured this limit, but it is indeed about 1 - 2 years, and longer if refrigerated (not frozen and never opened). Kodak and others made the decision to supply only liquid kits, and then to supply most of the chemistry in plastic bottles. This limits the lifetime.
PE
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yes, I was referring to the dry, raw individual chemicals to make up C41, RA4 or ECN-2 chemistry.
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just one data point: I have a one pound, brown glass jar of Kodak Hydroquinone that dates to the early 1970's. I'm slowly working my way through it. No special storage. It is a little bit brown-grey compared to the fresh stuff I bought a few years ago but still works fine.
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