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:
Do you know of more developer-chemicals that are glycol-soluble?
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
Mark Overton
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 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.
Conclusion is EG can be substituted for PG as long as you have no plans drinking it!
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
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
Perhaps one could consider if there exists a stronger grain solvent than sulfite that is soluble in glycol.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?