Mixing my own liquid developer, extending shelf life

[Fatih Ayoglu]

Moderator note: this topic was followed up here; further discussion can also take place in that thread: https://www.photrio.com/forum/threads/adding-koh-into-glycol-instead-of-water.214194

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Dear all,

So I would like to mix my own liquid developer and have the long shelf life for it so I don't keep mixing it fresh and use it when I need.

Before I start, I have 2 assumptions with my proposal
1) the old HC-110 has a very long shelf life, like years years long
2) phenidone in gylcol does have extremely long shelf life
3) so if I use glycol instead of water to prepare stock solution, I should have a syrupy concentrated solution which should have a long life, like HC-110

The chemicals in this 1000 ml concentrated solution will be;

• 20gr phenidone
• 14gr KOH
• 4gr Vitamin C
• 100gr Sodium Sulfite
• 3gr benzotriazole

then I can mix 1+9 with water for working solution, (This is SoftShot developer formula)

So my question is, would these chemicals go hand to hand in glycol or would it create some sort of unwanted chemical reaction. And would I have a long shelf life for the concentrated solution as I will use glycol instead of water.

Really looking forward to hear your opinions.

Best wishes,
Fatih

 

[lamerko]

You will need a sulfite-free formula. I also don't know what will happen to the potassium hydroxide - I don't think it's a good idea. Under the names Vitamin C, it can be ascorbic acid or ascorbate - there is a difference. I wouldn't bother with this formula…

 

[Fatih Ayoglu]

You will need a sulfite-free formula. I also don't know what will happen to the potassium hydroxide - I don't think it's a good idea. Under the names Vitamin C, it can be ascorbic acid or ascorbate - there is a difference. I wouldn't bother with this formula…

Hi,

Thank you for your reply, it is ascorbic acid for Vitamin C.

And you wouldn't bother, because the solution will not be stable or the solution is not useful (again this is SoftShot developer, only to create masks, nothing more)

 

[lamerko]

The ascorbic acid will react with the potassium hydroxide to produce potassium ascorbate and water. However, I do not know if this reaction would occur in glycol. Even if the reaction occurs, the separated water will reduce the viscosity effect. But I think the sulfite won't dissolve. Therefore, you will need a sulfite-free formula.

 

[Fatih Ayoglu]

The ascorbic acid will react with the potassium hydroxide to produce potassium ascorbate and water. However, I do not know if this reaction would occur in glycol. Even if the reaction occurs, the separated water will reduce the viscosity effect. But I think the sulfite won't dissolve. Therefore, you will need a sulfite-free formula.

Ok so I can create a liquid solution without sulfite. As it is a large quantity, I can always measure 10gr Sulfite per working solution (in 1+9 mix).

 

[lamerko]

It should work, but the sulfite solution will begin to oxidize to sulfate over time - it won't last too long.

 

[Fatih Ayoglu]

Thanks a lot. I can keep sulfite as powder. That is the best way probably and prepare the liquid ones with glycol to make them long lasting. The only problem is vitamin c as it is a tiny amount required in the actual working solution and measuring that is a pain. That’s why I’d like prepare a stock solution of that.

 

[koraks]

Sulfite should soluble in glycol. I don't know if you can get 1000ml of glycol to hold 100g sulfite plus the other stuff you intend to put in there.

I don't think the ascorbic acid to ascorbate reaction can occur without the presence of water as a solvent. It will occur instantly as you mix your concentrate with water. This should be OK.

Your idea might work. Try it out with a 50ml test batch and see how it goes.

Alternatively, there are several other concentrated film developers that keep well. Pyrocat comes to mind.

PS I doubt the NaOH will dissolve very well in glycol. I don't know if the ascorbate and phenidone will survive long in its presence, even in pure glycol. Maybe, maybe not.

Maybe @Alan Johnson and/or @Rudeofus could chime in. They know a lot more than I do.

 

[Fatih Ayoglu]

I use Rodinal and XT3 fort actual rolls and sheets.

However this developer is recommended as a very low contrast/gamma producing developer for contrast making with BW films.

I guess the best way will be, preparing each chemical in glycol and then mix before I create a working solution.

When I do that, the concentrated solutions should be stable for a very long time. (I suppose)

 

[retina_restoration]

Choosing a developer formula depends to a great deal what you define as having a “very long” shelf life. If you mean a year, that’s not hard to find. If you mean 3 years or more, the options are far fewer.
If I wanted something that will last at least two years (if stored properly) I would opt for either Pyrocat HD or even PMK. I make PMK from scratch and stored in a cool place, in brown glass bottles, it lasts for at least two years. Avoiding heat and light is critical in long term storage of developer chemistry.

 

[Alan Johnson]

Dissolving powdered developer in glycol?

I found a local source for propylene glycol. Does any one have experience dissolving powered developer in it? I'm having xtol in mind. Since it comes in such large packet, it would be nice if dissolving it in propylene glycol instead of hot water can make the stock last much longer. I know the...

www.photrio.com

See posts 5 and 6, OP I would not go there unless you have lab experience.

 

[lamerko]

sodium sulfite does not dissolve to an appreciable extent in propylene or ethylene glycol.

Yeah, that's what I thought too...

 

[Fatih Ayoglu]

So few things,
I use PG, not EG
I dont plan to go to 250F for any part, a standard 20C or to help the chemicals to dissolve 35-40C max. I cannot heat more in my darkroom
Sodium Sulfite is ok not to prepare as a liquid solution only because as I have mentined, the quantity in a 1 litre working solution is 10gr of SS which I can measure very easily.

It looks like, for the time being, I should stick to powdered parts and do not mix anything except, phenidone in glycol

 

[Andrew O'Neill]

That's a LOT of Phenidone! I would go for something simpler, like Gainer's PC-TEA.

100 ml triethanolamine (TEA)
9.0g ascorbic acid
0.2g phenidone

Heat to 80C until dissolved. If using a microwave (like me), heat up in increments of 10 seconds. Be careful! It heats up fast and can cause severe burns. Don't breath in the fumes.
dilute 1+50 with water to use. I often use it at 1+25

 

[Alan Johnson]

I believe the OP specifically wants to make Muir SoftShot developer concentrate.
The quantities of phenidone, ascorbic acid and benzotriazole specified in post 1 should all dissolve in propylene glycol according to this thread:

Solubility of photographic chemicals in propylene glycol

Pixophrenic submitted a new resource: Solubility of photographic chemicals in propylen glycol - stock solutions, non-aqueous solvent I would like to share a small compendium of solubility data of photographic reagents in hot (40-60 o C propylen glycol. The purpose is to have a long-life...

www.photrio.com

Two questions AFAIK not answered on Photrio remain:
(1) Will 14g Potassium Hydroxide dissolve in 1L glycol without excessive heating ? [careful experiment ?]
(2) If so, considering the relatively small amount of AA and the fact that excess potassium hydroxide will make the solution very alkaline if any water is absorbed, will this glycol solution be as stable as those that have more AA and are not so alkaline. [No but better than water ?]

 

[lamerko]

The weight of Ascorbic Acid is 176.12 while that of Potassium Hydroxide is 56.11. This suggests a small excess of KOH, but it is usually distributed at purity below 90%, so there probably won't be any excess. But it is not known if there will be any reaction in glycol at all...

 

[Sirius Glass]

The life killer for all developers is exposure to air and oxidation. Accordion bottles eventually, usually sooner than later leak. I use 1 liter StopLossBags™ from www.StopLossBags.com and with them I have keep developers and replenished developers working for years. These bags allow one to squeeze out all the air before tightly sealing. Be sure to buy their funnel to minimize spills and save as much developer returning the developer back into the storage bags.

 

[Andrew O'Neill]

The life killer for all developers is exposure to air and oxidation. Accordion bottles eventually, usually sooner than later leak. I use 1 liter StopLossBags™ from www.StopLossBags.com and with them I have keep developers and replenished developers working for years. These bags allow one to squeeze out all the air before tightly sealing. Be sure to buy their funnel to minimize spills and save as much developer returning the developer back into the storage bags.

Well, I've had my accordion bottles since 1991, and they are fine. I bought them in Japan when I lived over there. They are plastic but have an almost rubbery feel to them. They only develops I put in them though, are ones that I go through quickly (Pyrocat-HD for example). Other developers that use TEA or Glycol, I don't. A small, glass bottle is fine...If there is air in the bottle, no worries.

 

[Fatih Ayoglu]

I believe the OP specifically wants to make Muir SoftShot developer concentrate.
The quantities of phenidone, ascorbic acid and benzotriazole specified in post 1 should all dissolve in propylene glycol according to this thread:

Solubility of photographic chemicals in propylene glycol

Pixophrenic submitted a new resource: Solubility of photographic chemicals in propylen glycol - stock solutions, non-aqueous solvent I would like to share a small compendium of solubility data of photographic reagents in hot (40-60 o C propylen glycol. The purpose is to have a long-life...

www.photrio.com

Two questions AFAIK not answered on Photrio remain:
(1) Will 14g Potassium Hydroxide dissolve in 1L glycol without excessive heating ? [careful experiment ?]
(2) If so, considering the relatively small amount of AA and the fact that excess potassium hydroxide will make the solution very alkaline if any water is absorbed, will this glycol solution be as stable as those that have more AA and are not so alkaline. [No but better than water ?]

Thank you. This is the case.

Alternatively I can make each powder dissolved in PG for long lasting shelf life.
Except SS and KOH, SS I can use as powder as it is 10gr per 1 litre working solution

Right now my main question is, can I dissolve AA in PG to make a stock solution which I’ll take a bit to mix with working solution. Like if I can mix 4g of AA in 100ml PG, then I can take 10ml of this and mix with others to make working solution. And would this be a long lasting stock solution.

Edit: to answer my own question, apparently AA can be solvable in glycol up to 8% easily with over 1 year shelf life based on this: Patwnt

 

[Fatih Ayoglu]

That's a LOT of Phenidone! I would go for something simpler, like Gainer's PC-TEA.

100 ml triethanolamine (TEA)
9.0g ascorbic acid
0.2g phenidone

Heat to 80C until dissolved. If using a microwave (like me), heat up in increments of 10 seconds. Be careful! It heats up fast and can cause severe burns. Don't breath in the fumes.
dilute 1+50 with water to use. I often use it at 1+25

Per 1 litre working solution, there will be only 2g Phenidone. My plan was to prepare 1 litre of concentrated developer with 20g phenidone and take 100ml of this solution to mix with 900ml water to make working solution. So that would give me 2g if I’m not wrong

 

[Lachlan Young]

I believe the OP specifically wants to make Muir SoftShot developer concentrate.

Given that Softshot is evidently a modified POTA (but done a bit weirdly, with some questionable approaches - given what is now known about more optimal component choices), I reckon that something better would be achievable - albeit that you'd probably end up at roughly the same place as Adotech IV...

HQMS and a carbonate buffer would probably be less trouble overall.

 

[retina_restoration]

Per 1 litre working solution, there will be only 2g Phenidone. My plan was to prepare 1 litre of concentrated developer with 20g phenidone and take 100ml of this solution to mix with 900ml water to make working solution. So that would give me 2g if I’m not wrong

2 grams of phenidone in a liter of working solution is a LOT of phenidone! Most developers I make that use phenidone, use 0.1 grams per liter of stock solution!

 

[laser]

Well, I've had my accordion bottles since 1991, and they are fine. I bought them in Japan when I lived over there. They are plastic but have an almost rubbery feel to them. They only develops I put in them though, are ones that I go through quickly (Pyrocat-HD for example). Other developers that use TEA or Glycol, I don't. A small, glass bottle is fine...If there is air in the bottle, no worries.

Brown GLASS bottles are a good choice while using glass marbles to occupy the air space.

 

[Sirius Glass]

Brown GLASS bottles are a good choice while using glass marbles to occupy the air space.

I used glass marbles to displace the air in a large bottle and eventually discovered that the marbles make the bottle too heavy to conveniently use. I switched away from marbles, but I have not found a use for the marbles. I still have the marbles because I do not want others to say that I lost my marbles.

 

[lamerko]

2 grams of phenidone in a liter of working solution is a LOT of phenidone! Most developers I make that use phenidone, use 0.1 grams per liter of stock solution!

The low-contrast POTA developer contains 1.5 grams of phenidone. True, there is no ascorbate, but there is a huge amount of benzotriazole in this formula. But it's a really weird formula…