whats the best way/temp to store chemical concentrates

destroya

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I expecting a delivery of e-6 chemicals from a friend that are concentrates to develop 20+ liters of each solution. it appears most come in 4 bottles that each make 5 liters. so say i mix up 1 bottle to make a working solution. I will leave the other bottles obviously un-opened, so whats the best way to store them. my main question is relating to temperature. is it better to store them colder or warmer? what about the mixed working solutions? same question. colder or warmer? I will keep them in air-tight wine bags so no air can get into them and I have a nice tap for easy replenishing.

thoughts?
 

Svenedin

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Chemical reactions speed up as the temperature increases so cooler. Cool, dry and dark is a good general rule for chemical storage.
 

WilmarcoImaging

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Oxygen is the enemy, mainly with developers. Factory packaging stored cool, dark and dry is the best option. Working solutions prepared with distilled water and stored in wine bags with an EVOH layer is another good option.
 

koraks

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Just follow the storage instructions on the box. They're usually on there or in the datasheet. Generally storage temp between something like 10C and 18C, dry, and away from UV (day) light.
 

halfaman

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Cool storage (fridge) doesn't slow down oxidation appreciably in developers and fixers. Cold storage (freezer) may form precipitates that will not redisolve easily. Koraks indications is the way to go.

As already mentioned, oxygen is what you really need to control.
 

koraks

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halfaman said:
Cold storage (freezer) may form precipitates that will not redisolve easily
Click to expand...
Certainly. This may already become a problem with temperatures higher than those in a fridge (not even freezer) with highly concentrated solutions. RA4 developer comes to mind, which tends to throw down a precipitate (most likely carbonates) even in my on-home darkroom which never gets below 15C! Room temperature storage would be my personal recommendation.
 

RalphLambrecht

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cool but not below10C so all ingredients stay in solution,
 

RPC

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RalphLambrecht said:
cool but not below10C so all ingredients stay in solution,
Click to expand...

I agree, too cold and it ingredients can separate.

I do not do E-6 but my experience with C-41 and RA-4 is that the mixed chemistry can last a long time stored in full, tightly sealed containers, and in glass I haved had developers last years without degradation. I use no refrigeration but store in a cool place.
 

RPC

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Much colder than that and you will likely see precipitate, as I have when stored in my refrigerator, especially with RA-4. I have tried freezing developers and found that is a no-no, terrific amount of separation, and took a lot of shaking to re-mix upon thawing and not entirely successful, in addition to undesired oxidation.
 
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