RA4 Enviroprint Starter formula ?

[Sergejs Orlovskis]

Hello everebody, maybe someone knoe the enviroprint developer rtarter formula ?

 

[hka]

See page 22 and on...

 

[Sergejs Orlovskis]

I know how to mix 1l. chemicals from concentrate. I ask starter formula because for 1 litre MP45 developer witch I use need 130 ml starter for working solution and it is cheaper to use homebrew starter but I don't know the formula of it. In that manual is nothing about starter formula

 

[Rudeofus]

Some base formulas for C-41, E-6 and RA-4 were published in patent literature, but AFAIK none of the commercialized concoctions were ever made public. Big labs mixed these bathes from scratch sometimes, using formulas given to them by manufactures, but to my best knowledge they are all bound by strict NDAs.

 

[Analog Swede]

A formula?
Potassium chloride, maybe a tiny tiny amount of potassium bromide, a carbonate buffer and perhaps some proprietary additives? The msds for the product reveals no details! Colorless, no smell, no VOC, completely miscible in water. No grim varnings about fires, explosions, poisoning or other hazards.

I have checked a few patents about the amount of potassium chloride in a working developer. The intervall in them is 0.5 - 2.5g /liter.
You can find a lot of useful (but also confusing) information in patents!

Steven Keirstead has revealed a formula here: http://www.people.fas.harvard.edu/~keirst/technical/technical.html

If you calculate his addition of sodium chloride in a working solution you get 1.27g sodium chloride/liter.
With Potassium chloride: 1.62g/liter

Assuming that Keirstead's formula is correct (or at least close) and also assuming that the replenisher is totally void of chloride, a DIY starter at 130 ml per liter tank solution should contain 12g/liter potassium chloride.

I have not tested this myself and cannot guarantee anything!

Good luck!
Jonas

 

[Rudeofus]

And few of us will test this formula, as Lithium Polystyrene Sulfonate is not one of these compounds that we have just sitting in our shelves. And nope, Sigma Aldrich doesn't seem to carry it anymore, either, not that they would have sold to an amateur. In the same fashion it may not be easy to source Etidronic Acid (aka Dequest 2010) in the USA.

 

[mrred]

Wouldn't saving a bit from your old used batch, work as starter?

 

[Sergejs Orlovskis]

I don't like to do that. I develop pictures in Jobo CPP proc and use fujifilm MP45 developer 50 ml to 1 picture 15 x 20 cm. This method gives best result but need to do fresh solution of developer any time when 1 litre ednds I doing new. I try to put used defeloper back in jobo bottle and replenish it as written in developer manual. But it doesn't work to small quantity of developer and developer become bad after 2 - 3 days if fresh developer is mixed with used developer. But fresh developer lives 2 -3 weeks. I ask about formula because starter coasts as 1 developer bottle and for 1 litre I need 130 ml starter

 

[Rudeofus]

So the problem appears to be that Fuji's RA4 starter is only sold in amounts seven times of what you need, and that its shelf life is shorter than the interval between two dev sessions.

One possible way to solve your problem is starting with this recipe which you then replenish with your Fuji replenisher. RA4 is, after all, a standardized process, which means the starters should be very similar.

 

[hka]

1 Liter RA4 Developer Starter cost you about € 10,=?
What I can recommend to do is fill 4 bottles of 250ml each with the fresh developer. Top off and use one of them for the first 5 excersises and so on...

 

[Sergejs Orlovskis]

I found the formula. According that PDF Starter is NaCl 3- 10 % solution . I Use kitchen salt 97% NaCl 10% per 1 liter and it is works

 

[Rudeofus]

Good to hear that you found a working substitute for C-41 starter, yet I somehow doubt that 3-10% NaCl are the whole story. That MSDS you posted doesn't even contain the NaCl, but it does list a specific weight of 1.153, which you won't reach even with 10% solution

BTW: Fuji's MSDSs go to the limit about not listing relevant contents of their chemicals. Look at this color fixer MSDS, only the sequestering agent for water hardness is listed, which by itself most definitely won't fix film.

 

[Sergejs Orlovskis]

It is RA4 starter. In C41 fuji use Pottasium carbonate and I use another MSDS View attachment RU_979328.pdf it is the saame starter but in Russian. And there in 3 capter is saing that starter is codium carbonate solution. I use 10% solution of kitchen salt 100 gr per liter

 

[Rudeofus]

Again, an MSDS provides no complete ingredient list, it may (and usually does) leave out any compounds which are contained in low concentration and/or which are not overly toxic. I showed you the Fuji MSDS for their color fixer, if you trust that MSDS you'd think it doesn't even contain Thiosulfate.

BTW if you add kitchen salt, you add not only Sodium Chloride, but usually also some amount of some form of Iodide.

 

[Sergejs Orlovskis]

Maybe You write, but I use kitchen salt 10 % sollution and it is work great for starter. It doesnt have sodium iodide because in Latvia we have speciam iodide salt

 

[RPC]

The Fuji C-41 starter you mentioned would likely contain bromide as well. That is the principle ingredient lacking in C-41 replenishers.