Confused about kodak RA4 chemicals

Yes, original factory plastic bottles for the unmixed concentrates themselves, or an akin thick poly plastic.

There are various ways to introduce inert gas into a container and displace the oxygen. Rented argon or nitrogen tanks could be used. But on small scale, you can quite affordably acquire small containers of inert gas intended to keep opened wine bottles fresh tasting. They're even listed on Amazon. I don't remember specific brands names, but they'd be easy to search under wine preservative canisters.

Drew you’re the man, thank you for this insight.
I’m about to buy high volumes of chem & definitely want to make sure I stretch it’s value as long as possible.

Last question, if I wanted to attempt to stretch the chemistry even longer & attempt to preserve (mixed) chemistry from a session (from drum professing) - what would be the best practice, if any?

(thinking like a doomsday prepper in the event that we’re all SOL obtaining Kodak RA4 chem)

Thanks,
-b

Keeping the mixed solutions around longer? It's analogous to what I already recommended for the concentrates themselves - impermeable virgin poly or glass containers, and air displacement inside using an inert gas.

My own problem at the moment is having the RA4 chemistry on hand, but waiting seemingly forever for my preferred paper to arrive. Another symptom of covid.

Brent Waterworth said:

*Bump*
I wanted to get some insight for preserving chemicals.
Right now, Kodak RA4 chem seems to be really hard to get my hands on but I did find a spot in LA that has large volume quantities of the Developer Replenisher (25gal.) & Blix Part A & Blix Part B (both 100L).

What’s the best way to stretch the shelf life for this?
Obviously keeping it in concentrate form & only mixing per session as needed. (I’ll be doing drum processing as one shot)

Do I need to buy specific storage containers/bottles/etc. to keep the concentrate as fresh as possible? I understand people using soda bottles with the air squeezed out - does this apply for the chemicals as soon as I open them & begin my first session?

Any help/advice is greatly appreciated.

Thanks
-b

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For longest life, mix all developer at once and store in glass bottles, filled to the top and sealed tightly. It can last much more than a year this way and give excellent results. I know, because I have been doing it for years, and Kodak recommends this. I would never mix from concentrates as needed. Once the bottle containing the developing agent is opened, it will not last as long as mixed developer stored in the above manner, at least not in my experience.

A 25 gallon mix may be problematic doing it this way because of the size, and its component bottle sizes and numbers, which I am not familiar with.

I store in canning jars. They are glass, and seal tightly. They are available in many stores, are relatively inexpensive, and come in different sizes. This allows you to keep bottles as full as possible as you are using up developer.

As for bleach-fix, it should be used within a couple of months after mixing.

RPC said:

A 25 gallon mix may be problematic doing it this way because of the size, and its component bottle sizes and numbers, which I am not familiar with.

I store in canning jars. They are glass, and seal tightly. They are available in many stores, are relatively inexpensive, and come in different sizes. This allows you to keep bottles as full as possible as you are using up developer.

As for bleach-fix, it should be used within a couple of months after mixing.

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Sorry, i think it may actually yield 25gal. It appears the actual contents of the RA Developer Replenisher is 12.5gal. (see attached).

I basically either need to figure out the best way to keep this stuff stored properly so I can extend the life of it for as long as possible (or) I need to return it within 30 days to get my money back.

Obviously since it’s so hard to get this stuff right now & i’d love to make it work, whether that best practice is keeping it as concentrate & using as needed (or) pre-mixing everything & portioning out into glass bottles (air tight, etc.)

All in all this put me back a few hundred $USD so I really just want to make the right decision here. After all, what good is having the chemistry if the chemistry is no good…after a short window of time.
Seeing how I would be most likely doing 1/2 day sessions using a drum processor & not huge high volume print production, I just want to be realistic.

I did also find these brown glass bottles on Amazon (see attached) & although they are only 16oz. & would require lots to have for pre-mixed chem, im curious if this is the better option over glass mason jars with lids?

Again, any & all advice/insight is greatly appreciated.

Thanks guys,
-b

With that much, you might try decanting the developer components, most importantly the developing agent (part B) into smaller full glass bottles, but It is unpredictable how long the developing agent will last after this. Then use them up one at a time, mixing up whatever amount that will make and storing in full bottles.

The other choice is to mix it all up at once, a lot to mix and store, but will give the longest overall life.

Look for Amber 1/2 gallon and quart size growler bottles (as in for beer) with good caps. The finger handles are really a good safety feature.

StopLossBagsTM are bladder bags that one can squeeze out the air. www.StopLossBags.com

Thank you all for the helpful advice.

Do these suggestions only apply for the developer?
Should I keep both of the Blix components separate & store in those same amber bottles? Or is it best that i mix both parts (A + B) & store them the same way as well?

I’ve never mixed/stored my own chem before so this is all a first. Luckily my garage/soon to be darkroom has no windows & with the dry Los Angeles climate id imagine it’s pretty ideal to store this type of stuff long term.

Thanks,
-b

Brent Waterworth said:

Thank you all for the helpful advice.

Do these suggestions only apply for the developer?
Should I keep both of the Blix components separate & store in those same amber bottles? Or is it best that i mix both parts (A + B) & store them the same way as well?

I’ve never mixed/stored my own chem before so this is all a first. Luckily my garage/soon to be darkroom has no windows & with the dry Los Angeles climate id imagine it’s pretty ideal to store this type of stuff long term.

Thanks,
-b

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precip
The clear solution of the blix is the fixer part of the blix. This part, the clear fixer part is sensitive to oxygen. Left open or exposed to oxygen it can precipitate out sulfur and end up a stinky ruined mess. I have kept the clear portion of RA4 blix stored for years in absolutely full, no air, HDPE bottles. I have used Gatorade bottles, glass bottles etc. I have found the dark reddish brown, bleach part of blix to keep well in the original bottle for years.
Developer Replenisher concentrate should be stored in absolutely full bottles, I would use the same plastic type as what was used by the manufacturer. Some plastics like PET are embrittled by alkali solutions. Try not aerate the solutions when decanting.