Improved version of DS-10 by Ryuji Suzuki?

[albada]

What puzzles me is why is propylene glycol choosen as a container? Concentrated blue engine coolant is easier to get and may in fact be better suited to the task.
Trond Solem.

First, thank you for contributing to this thread. I seem to remember that you are the creator of the excellent Caffenol blog. Is that true?

I chose propylene glycol because it's much less toxic than ethylene glycol. Also, the engine coolants available in America (are you in Europe?) have many additives in them, and I don't know what they'll do in a developer. So I was forced to order the glycol online, and PG is easy to buy online.

I'm keeping a list of chemicals that can dissolve in PG:

Phenidone to >= 2% (g/ml)
Ascorbic acid to >= 20% (g/ml)
Hydroquinone to >= 20% (g/ml)
Borax deca/pentahydrate 21.53% weight/weight (25C)
Boric acid (in insecticides)
Sodium metaborate
Citric acid
Benzotriazole

​

Do you know of more developer-chemicals that are glycol-soluble?

Mark Overton

 

[Alan Johnson]

Metol and Glycin.They have to be reacted with small amounts of TEA and water first, as described in the mixing instructions for Pyrocat-MC section F:
http://www.pyrocat-hd.com/html/mixing.html

 

[Tronds]

First, thank you for contributing to this thread. I seem to remember that you are the creator of the excellent Caffenol blog. Is that true?

I chose propylene glycol because it's much less toxic than ethylene glycol. Also, the engine coolants available in America (are you in Europe?) have many additives in them, and I don't know what they'll do in a developer. So I was forced to order the glycol online, and PG is easy to buy online.

I'm keeping a list of chemicals that can dissolve in PG:

Phenidone to >= 2% (g/ml)
Ascorbic acid to >= 20% (g/ml)
Hydroquinone to >= 20% (g/ml)
Borax deca/pentahydrate 21.53% weight/weight (25C)
Boric acid (in insecticides)
Sodium metaborate
Citric acid
Benzotriazole

​

Do you know of more developer-chemicals that are glycol-soluble?

Mark Overton

No, I am not the creator of the Caffenol blog.
I am just a computer and electronics engineer with great interest in photo and photographic processses.
I have worked at a large photo finishing lab for some time, but that is some years back in time.
Since I am used to set up and run test of different kinds, I am a practical kind of guy. I read about things and if it sparks my interest, I set up and run a test.
If it works, well, great. If it doesn't work, well, that is valuable information too.

The additives in engine coolants doesn't play havoc with developing agents as far as my experiments shows. They even may help us protect the developing agents from oxidation since they are introduced to prevent oxidation of engine components. One downside is that they contain lubricants to protect the waterpump bearings from wear. How much of a problem that is can be discussed. In working dilutions of 1:50 it doesn't seem to be a problem. The developer wets the film evenly without any problem.

BTW. Engine coolants DO contain borax. Maybe the amount of added borax can be reduced since some borax is already in the liquid?

Propylene glycol is difficult to find here in europe, at least here in Norway. Cheap engine coolant is availabe at every gas station. They may differ somewhat in what and how much anti-corrosion additives they contain, but borax is by far the additive in highest concentration.

Sodium hydroxide pearls can be dissolved in small quantities in ethylene glycol. I suppose it may be dissolved in about equal small quantities in PG.
4-5g in 100ml engine coolant is ok. If more can dissolved I don't know, but it isn't important, since 4g is already too much.

I just read that popylene glycol wil degrade rapidly in air.

From: Dead Link Removed

Degradation: In air, half will break down within 24-50 hours. In water and soil, it will break down within several days to a week.

If this is correct, propylene glycol is not the container to use.
Can anyone comment on this?

Trond Solem.

 

[Photo Engineer]

From: http://www.ams.usda.gov/AMSv1.0/getf...TELPRDC5067083

Degradation: In air, half will break down within 24-50 hours. In water and soil, it will break down within several days to a week.

The above quote is inaccurate and misleading in this context. PG is very stable up to quite high temperatures. I think that they are referring to degradation in the open environment. In that case, a human body will go bad in about the same time perion!

Both PG and EG are stable but EG is very much more toxic. Otherwise, their properties are quite similar for our purposes here.

Both taste sweet and attract children and animals due to the sweet flavor. EG kills the subject, but PG can be used as a food additive.

As for heating either with water, you run the risk of water boiling out. IDK what temperature is bad here due to the nature of both alcohols and their interaction with water.

PE

 

[analog what is that?]

Conclusion is EG can be substituted for PG as long as you have no plans drinking it!
Both works and under normal circumstances (not trying to put any esoteric chemicals into the mix) no excessive heating nor boiling takes place; EG is perfect because it can be found anywhere there is a gas station.

I use EG, in the meaning of engine anti-freeze concentrate (no water added), but prefer a simpler mix than Trond, but for me ts a fine container of AA and Phenidone (PC-Glycol) that last more than long enogh for me.

 

[Photo Engineer]

Umm, that is if the EG in antifreeze is free of ingredients that harm film or imaging. No one has come forth and proven that one yet!

PE

 

[Tronds]

Umm, that is if the EG in antifreeze is free of ingredients that harm film or imaging. No one has come forth and proven that one yet!

PE

The number of films I hva developed in PC-glycol with EG proves that.

Absolutely no negative results except the negative itself, which in fact is positive, or well, it is a negative.

Remember that it is formulated to not attack rubber hoses, aluminium or other metal parts in the engine at high temperatures.


I have tried just one brand of engine coolant, but if you try the cheapest one with the least advertized snake-oil additives you should be safe.
I havent tried the red long-life versions since the blue one is more than good enough for the task.

 

[analog what is that?]

Very simple PE or anyone else, just look up the recipe for PC glycol, go to the auto parts store or where appropiate and find one bottle of concentrated anti-freeze, blue type. Mix and test for yourself, it will be a peach.

This is for PRACTICAL people, not theorizing.........
If one haven't tried for oneself, there is no business telling anyone this will not work - on the other hand if one tries it, and reports back it did not work, it is very interesting to be part of the team figuring out why it did not work and what was done wrong - because it works without any trouble at all, when done properly.

 

[Alan Johnson]

The concentrated ethylene glycol antifreeze I found locally in 2 versions:
For cars made after 1998-silicate free organic acid technology.
For cars made before 1998-not stated.
I wonder if there would be a preference for one of these two types.

 

[Tronds]

The concentrated ethylene glycol antifreeze I found locally in 2 versions:
For cars made after 1998-silicate free organic acid technology.
For cars made before 1998-not stated.
I wonder if there would be a preference for one of these two types.

The first version is probably the long-life version that I never tried.
Go for the version for cars made before 1998.

If you can test pH of the silicate-free organic acid technology version and parhaps mix a small batch to see if it works, it would be great.
Don't use it on a film with important pictures though.
It may be even better, but it may also be a total disaster.

You can read about antifreeze here: http://en.wikipedia.org/wiki/Antifreeze

Note the part about propylene glycol.

A little bit of poison in the solutuion may be beneficial since it inhibits bacterial growth.

 

[albada]

Conclusion is EG can be substituted for PG as long as you have no plans drinking it!

I would worry that the manufacturer might change the formula of the antifreeze. For example, Trond mentioned that it contains borax. If the manufacturer changes the amount of borax next year, the pH will change, and the developer's activity will change. That's why I want to use pure chemicals: I'm guaranteed to get the same results every year.

Having said that, I agree about using EG: I would be happy to use pure EG. I can safely change antifreeze in the car, so mixing EG in a developer is no problem.

Mark Overton

 

[Photo Engineer]

As for practicality, my formulas have been on sale commercially since about 1970 and in modified form the first one is still being sold by Kodak. So, I have a lot of practical experience. I was also present during the development of some of the formulas mentioned here and knew the players in this area.

Now, here is something for you to think about!

I have used a particular home brew process and the results looked good, but I run keeping tests. After 5 years, some processed examples are showing varying degrees of brown or orange stain. These samples all looked identical at the start. I did run some analytical tests 5 years ago and found some differences between the samples. This is not related to the present case, but does show how things can go bad with keeping.

The blue color is a dye. Who cares what color the inside of your car radiator or coolant tubing is? We do care about the color of our film! So, what if the blue colorant or film vehicle changes due to manufacturing changes by the companies involved? The film may end up blue! And, the blue color may change with time and pH as the CO2 in the air changes the pH of the film.

Here are two theories based on practical results that I have observed in the lab at one time or another.

So, as I said above, no one has proven that anti freeze is a fool proof solvent, and no one can prove that it will remain so into the future. If you are doing this, it is worth doing well, but then after all, these are only your photographs..

Have fun with these ideas.

PE

 

[analog what is that?]

Naaa that is an argument without any practical merit in THIS context.
We are not developing color films you know, (most of us) are not printing in the darkroom any more, fewer will in the future.
We employ a modern gizmo called a scanner. This thing cuts through bot fog and color dyes like a knife in butter.
It is also fully color sentisive, so we can scan any color we, like and change the colors afterward or even turn the thing into B/W with just one click on a virtual button...

So this was an answer looking for a good question....

For your information we come from a running debate on Caffenol, where the guys demand to exchange KBr with iodized table salt, large amounts of it, and accept the acompanying yellow stain as if nothing happened....

 

[analog what is that?]

Practical experience is outside a lab, with no million dollar funding in my book.

I have worked with quality control in a traditional chemistry based lab for years and know the difference between my old lab workstration and my kitchen bench. Unless you have done both you won't know thge difference....

 

[analog what is that?]

Mark I would NOT worry over the manufacturer changing the formula: I would worry over the SELLER changing his supplier.......

However that turnsw out to be a small or no problem, in my those changes are accompanied by very literal changes in packaging, literal and very noticeable, and most often with drastic color changes as well.

Is that a problem? On the conbtrary, it's an opportunity!

An opportunity for another string of tests, finetuning and improvement. After all the world is supposed to move forward, it will only do so through hard work.

 

[Photo Engineer]

Well, I have a number of developer and fixer formulas on sale right now that were designed in my home darkroom with no million dollar lab at my disposal. So, I have done both high end and low end.

I have done lab scale and pilot scale work on emulsions at EK and have replicated them in my home darkroom to the extent that I have duplicated Azo paper (for those still into darkroom printing). And that brings me full circle! what makes you think that a potential blue stain would be uniform? And, what does a non-uniform stain do to a print or a scan? Hmmm?

So, have fun.

PE

 

[Hexavalent]

There is an inherent risk in using products "off label" - manufacturers can, and will alter their formulations at any time. Their only responsibilities are to retain the functionality of their product for its stated purpose. MSDS sheets need only list hazardous substances, and even then, the word "proprietary" protects the manufacturer from having to reveal specifics.

In other words.. proceed at your own risk! It's often the 1% of a "99%" product that causes havoc. Been there, done that.

What's the point of producing a negative that has to be corrected by means of scanning/software? That's not what I'd call an analog process.

 

[Tronds]

The blue color is a dye. Who cares what color the inside of your car radiator or coolant tubing is? We do care about the color of our film! So, what if the blue colorant or film vehicle changes due to manufacturing changes by the companies involved? The film may end up blue! And, the blue color may change with time and pH as the CO2 in the air changes the pH of the film.

PE

Well, the blue color IS a dye, but don't you wash your film after fixing? I do. I wash the film to that extent that if a blue colour shows up in 5 or 10+ years, it isn't because of the dye in the glycol, but from any chemical stored next to the film during that years.

I would worry a bit less and be happy with what works at the moment. What is going to change tomorrow, next year, or in ten years, we can't do anything with today.
Your developer formulas may also be worthless in 10 years if the film manufacturers changes the way the emulsion is made.
If that happens, we have to start over and make a new developer then. If we are afraid of trying things today, we won't have any experience when that happens.

 

[Photo Engineer]

I could give you a dye suitable for radiator fluid that you might not be able to wash out of film or that might shift color unpredictably.

As for films requiring a new developer formulation, not gonna happen. The R&D needed would cost too much in the face of the current market.

So, remember that I am only suggesting prudence in this and the use or "real" PG or EG and I am only pointing out (along with a few others with chemistry experience) what might happen based on similar experiences.

My bottom line, expressed many times here, is "use what works for you". Just don't complain if things go wrong. I have spent hours answering PMs or threads here explaining what went wrong. And, sometimes nothing does go wrong.

PE

 

[Tronds]

I could give you a dye suitable for radiator fluid that you might not be able to wash out of film or that might shift color unpredictably.

As for films requiring a new developer formulation, not gonna happen. The R&D needed would cost too much in the face of the current market.

So, remember that I am only suggesting prudence in this and the use or "real" PG or EG and I am only pointing out (along with a few others with chemistry experience) what might happen based on similar experiences.

My bottom line, expressed many times here, is "use what works for you". Just don't complain if things go wrong. I have spent hours answering PMs or threads here explaining what went wrong. And, sometimes nothing does go wrong.

PE

The blue colour used in coolant will wash out. They won't introduce a colour that makes the hands of mechanics permanently blue or any another colour. The colour used in tax-free diesel here in Norway is another story. It won't wash out completely in any way. This to make it possible to detect if a car is run on tax-free diesel sometime in it's lifetime. That to make it possible to wite a fine of several tens of thousand dollars to the present owner.

The amount of borax already present in the coolant isn't going to dictate the resulting pH in any way. The amounts we introduce is way more so it is of no concern to us.

I don't like to take negatives aspects into concideraton before they in fact are a reason to rethink. This may occur if we are warned that something is going to happen with the composition of either the film or the glycol we are using, OR when we discover that something has in fact changed.

I would be more concerned about the keeping qualities of pure propylene glycol. It oxidizes in contact with air,AND is it prone to bacterial growth since it isn't toxic.
What happens when the developer is attacked by bacteria that eats ascorbic acid or sodium ascorbate? If they produce something that destroys the phenidone it would be just perfect, or not.

Trond Solem.

 

[Photo Engineer]

Well, if PG is so unstable, then how does HC110 keep so well as a syrup?

If AA is chewed up by bacteria so easily, then how does any PG/AA developer concentrate survive?

The answer is out there! Bacteria don't like Borate, Sulfite, TEA, DEA etc, etc, etc! And PG is not as unstable as the earlier reference seems to indicate.

PE

 

[Gerald C Koch]

Whether or not a particular chemical is toxic to higher life forms is not a good indicator of whether it is toxic to bacteria. There is at least one species of bacteria that metabolize arsenic and another that does so with hydrogen sulfide. To cite only two examples. Bacteria are going to be inhibited by the high osmotic pressure of the developer concentrates and the lack of water.

Both ethylene glycol and propylene glycol are suitable as solvents for developer concentrates. Unless there is a chance of a human or pet drinking the glycol either one is usuable. Both are quite stable.

While I am in favor of using pure ethylene or propylene glycol there a places where these chemicals are not readily available. Using antifreeze may be acceptable if someone carefully tests them for the purpose of developer concentrates. Some brands may be better than others.

 

[Alan Johnson]

I don't think one can make a developer with a grain as fine as Xtol starting from a sulfite glycol concentrate.
The working solution of Xtol has 85g/L of the grain solvent sodium sulfite (FDC p49)
One would need to find an organic sulfite completely miscible with glycol and use a great excess of it if the mixture is to be both a concentrate for dilution and provide 85g/L sulfite equivalent in the working solution.
Even if it was possible it would be wasteful and expensive.
Perhaps one could consider if there exists a stronger grain solvent than sulfite that is soluble in glycol.

 

[Photo Engineer]

Alan, there are several silver halide solvents that fit your criteria. EK R&D people were working with a whole family of them when the work was shut down.

Jerry, think about antifreeze formulas all over the world! Each one may differ enough to cause problems in otherwise identical developer formulas and that is one of the problems using antifreeze.

PE

 

[albada]

Perhaps one could consider if there exists a stronger grain solvent than sulfite that is soluble in glycol.

Alan, funny that you should mention this. If you go back in this thread a few pages, there are a few postings where Ron and I talked about this. I read Ron's patents and got some ideas, and Jerry also contributed a couple of suggestions, such as Cysteine (pure; not a salt). Even if no halide solvent is workable, I have no problem mixing the sulfite separately from the concentrate. Sulfite doesn't need to be measured very accurately, and I noticed that a plastic film-canister holds 96 g of sulfite. So fill one almost full, and that's what Xtol/Mytol need for a liter. Or half full for 500 ml (2 rolls). My point is that folks can use a concentrate/sulfite duo conveniently enough, so we really don't need to incorporate the solvent into the concentrate. That's makes engineering a concentrate that much easier.

Mark Overton