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Rajsami 28th December 2019 11:59 AM

RA-4 Blix Storage (Long Term)
 
Hi guys,

I was just wondering if I could get some advice of how to store RA-4 blix for up to a year if possible. I just picked up the Kodak RA/RT LU kit and have done a few years of printing but this is my first time with the Kodak chemicals. I know that c-41 blix can be a bit unstable when mixed together. Is the RA-4 blix best stored as concentrate separately or as a working solution?

I'm also planning to use glass 1l bottles to store the mixed Dev in but do I need to use glass for the LU kit as it has good anti oxidation properties?

Any advice is much appreciated

Thanks

John King 29th December 2019 06:36 AM

RA4 Blix
 
I am assuming you use a deep tank processing system.

The Kodak RA4 is my chemical of choice for colour printing and have found that the developer and blix will keep as a mixed ready to use part of the process for many months. How many exactly, I have not measured, but over 6 month is certainly possible. In the past for one mix, I did not actually change the developer for over 12 months and it was still working very well as it was religiously replenished at the end of each session regularly. In that time as a precaution I completely changed the blix once.

I store the mixed blix in 1/2 litre glass bottles and the pre-measured replenishment in 100cc bottles which are enough for an evenings printing. After the initial mix has been made for the NOVA tank I only mix further quantities of working solution at the rate of 1 litre a time. I use glass bottles as a matter of course but if you use thick plastic bottles such as the type the stock solution comes in, that is perfectly fine.

Part used blix has a limited life of several weeks only, but this too can be extended with regular replenishment. If you use a deep tank processor replenish the diluted solution at a rate of 10cc per 80 sq inches of paper (1 x 10x8 sheet) which is the same as the developer.

The life of the blix will assisted if a stop bath is also used after the development stage and also replenished at the same rate as the other two. If you use an indicator type ignore this because you will not be able to see the colour change.

When it does go off, the colour changes from a clear dark burgundy colour to a muddy brown shade and has a noticeable unpleasant smell. This is the time to change it and flush out the tank.

Rajsami 1st January 2020 11:14 AM

Thanks for the response John. That helps a lot.

Have you ever found the 2 parts of the blix to react with each other when stored Luke this?

Also is it possible to over replenish? Or is that a good thing?

Thanks

John King 1st January 2020 04:56 PM

Bleach
 
No they are designed to work together, but use a stop bath before using the blix.

Possible to over replenish but highly unlikely if you stick to the 100cc per 80sq ins of paper ratio. Having said that, I have over replenished by 50% with no ill effects.

Rajsami 2nd January 2020 05:39 PM

Okay thanks for the help John. That all seems pretty foolproof to me... At least I hope haha


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