PDA

View Full Version : Improved version of DS-10 by Ryuji Suzuki?



Pages : 1 2 3 4 5 6 [7] 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

Gerald C Koch
12-22-2011, 11:29 AM
The chemical maxim that like dissolves like is true. Borax, an inorganic salt, is insoluble in methyl alcohol, an organic solvent. Diols, where the two -OH groups are on adjacent carbons, such as the glycols presents a special case with borates in that they form borate esters. This increases the solubility. The large water of crystalization, 10H2O, also helps.

Gerald C Koch
12-22-2011, 11:33 AM
My earlier post was incorrect in that I said that sodium metaborate is borax. I really shouldn't post things late at night when I cannot sleep. What I should have written was sodium tetraborate. My bad.

Alan Johnson
12-22-2011, 12:09 PM
Concerning how much water is allowable in TEA before oxidation occurs, Pat Gainer originally suggested 100ml water per liter of TEA (this was a method he devised so that PC-TEA could be made at low temperature).I tried this and found it failed after 9 months.Pat Gainer then revised his recommendation to 10.2 ml water per 1000 ml TEA but I have not seen any reports on the keeping of this.Anyhow, 10% water definitely fails quite rapidly.
It's in this long thread:
http://www.apug.org/forums/forum37/28518-homebrew-xtol.html

Photo Engineer
12-22-2011, 12:33 PM
Anhydrous Boric Acid is soluble in low molecular weight alcohols and poly-alcohols such as PG and EG. Not very, but soluble nonetheless. Sodium salts of Boric acid are not very soluble and any solubility is probably due to the waters of hydration. Boric acid + TEA forms a salt which may or may not redissolve. I have not tested this. In any case PG is better than EG from a toxicological standpoint and either is better than antifreeze due to the anti-rust chemicals in antifreeze.

The problem is that one must exclude oxygen and water from the concentrate. Kodak spent millions doing this and designing foolproof equipment to make hC110. Heating something on the stove can cause severe problems. When heated, and EG or PG mix with water in it can "bump" or create bubbles explosively when the temperature reaches or exceeds 100C. This can then cause the liquid to boil over and can create a fire if one is not careful. In addition, at this temperature EG and Phenidone create fumes that are not human friendly. Although the fumes from Phenidone are rather pleasant in odor, I don't believe you should subject yourself to the problem.

You need alkali, an oxygen scavenger (antioxidant) and a silver halide solvent that are soluble in one common solvent without water. There are chemicals that fit these criteria and still allow admixtures with developing agents. I repeat again - this can be done.

The adducts mentioned above may be available commercially and should be used if possible. This is the Sulfur Dioxide adduct of TEA and the HBr adduct of TEA. They can be home made at great expense and with great risk!

PE

Tronds
12-22-2011, 02:07 PM
Tronds,

When heated sodium metaborate decahydrate (borax) will dissolve in its own water of crystalization. I suspect that something similar is happening with ethylene gycol in that the borax is dissolving in what is essentially a mixture of glycol and water. This points out a problem since the purpose of using glycols is to provide a waterless solution to prevent oxidation of the developing agents. Inorganic compounds with water of crystalization will defeat the concept of a water-free developer concentrate since they add water to the solution.

Thanks for mentioning this.

Jerry

Let me see....... Where did I write heating or hot?
Scanning my text.... .... .... .... .... ... .... Nope. Didn't write anything about heating.
So, when I dissolved 20g borax in 75ml. etylene glycol WITHOUT heating, did it dissolve in it's own water?
If so, just placing it in a bottle on the bench should give the same result. It should dissolve in it's own water.
Surprise! It doesn't!

Try to dissolve 20g borax in 75ml methylated spirits. (Denaturated ethyl alcohol 95%.)
You can use as much heat as you want, but you can't make the borax dissolve "in it's own water" in ethyl alcohol.
In other words: It won't work!

From http://incidetech.net/tdsborax5mol.pdf

When heated in a closed tube, SODIUM BORATE begins to melt in its own water of crystallization at 128oC (262oF) and
is completely fluid at 140oC. Heated in the open, SODIUM BORATE loses its water of crystallization to complete
hydration and fusion at 742.5oC (1367oF)

Dissolving the borax was absolutely no problem. In fact, engine coolant DOES contain borax in it's concentrated form.
Solubility in propylene glycol at 25C is about 30% according to what I can find.
Solubility in ethylene glycol at 25C is 41.6%

That is way more than 20g in 75ml, is there is no need for heating the glycol to dissolve it.
Besides that, you need to heat the glycol/borax to 128C to make it dissolve in it's own water.
When I can handle the bottle with my bare hands, it is in no way close to that temperature.

So, how much water does 20g borax decahydrate contribute with?
About 6.42g.
In 100ml soluton this is about 6.42%
Does this render the solultion useless for storing developing agents? I don't think so.

What if you heat the ethylene glycol above 100c? Does the 6.42g of water evaporate?
Yes, it will.

So if you think this minute amount of water is a problem, just heat the glycol-borax solutuon above 100c fo some minutes.

BTW, engine coolant glycol is designed to protect the engine components from oxidation. I suppose it will do the same for developing agents.
In engines it protects from oxidation down to a concentration of about 30%. 6.42% water and 93.58% of etylene glycol mix is far more than 30%.

Maybe, but just maybe it will reduce the shelf life from 10 years down to 9.5 years, but I don't care. If I can't use 100ml of PC-glycol in 9 years, I just have to mix caffenol the few times I need to develop a film.

albada
12-22-2011, 02:14 PM
The chemical maxim that like dissolves like is true. Borax, an inorganic salt, is insoluble in methyl alcohol, an organic solvent. Diols, where the two -OH groups are on adjacent carbons, such as the glycols presents a special case with borates in that they form borate esters. This increases the solubility. The large water of crystalization, 10H2O, also helps.

Fascinating exception to the rule.
Here are a couple of tidbits that I forgot to mention which support what you said:

borax.com states that 21.53% of borax pentahydrate can be dissolved into PG (weight/weight). I don't know about decahydrate. Also, I'm leary of putting any borax into PG because of the H2O, and that's partly why I avoided it in my proposed developer from yesterday.
Boric acid is commonly mixed with PG in insecticides used to treat wood such as Bora-care, Penetreat and Timbor.

My question: Will the borate esters affect the functions of boric acid and sodium metaborate in a developer?
I think prior postings have already said "maybe" regarding boric acid, but how about metaborate?

Anyway, if borates dissolved in PG will function okay, then that's a good tool to have in our toolkit.

PE: Thanks for the warning about heating PG to 100C. What temperature do you think would be enough to drive out the H2O? When dissolving components into PG, I'd like to use a temp that's hot enough to keep H2O out, but no hotter.

Mark Overton

Tronds
12-22-2011, 02:30 PM
PE said inorganics should precipitate out. Could you try heating a sample of this mixture to 100C to drive out any water? Also, you can measure the volume or weight of the sample before and after heating to test whether some water was lost. I'm curious about this.

Best,

Mark Overton

I didn't heat it to dissolve the borax, but I had to heat a bit to dissolve the lye pearls and the sodium ascorbate. Not more than 50c though.
When heated and cooled again, it stayed in soluton, nothing precipitated out.

Heating to more than 100c will drive out any dissolved water, but since the engine coolant is designed to protect the engine components from oxidation, even in a 30% mix with water, I think this will be quite fine with the 6.42g of water introduced by the borax decahydrate.

Besides that, you need to heat the glycol-borax soluton to above 128c to split the water from the borax molecules. Storing at 20c or even 30c is quite safe if you think of it. This according to the datasheets for borax.

In an eralier attempt, where I tried to introduce 2g sodium metabisuphite in the solution. That won't dissolve. Adding 5ml of water made it possible to dissolve some of it, but not all of it.

Borax has the ability to bleach out colour of liquids. In the version with 5ml of water, it lost it's blue-green colour in 24 hours.
Without adding the 5ml of water, nothing happened.

Both versions is stored in bottles, so I will test both after 6 months, and after a year if both are still active after the 6 month period of storage.
The version with water and sulphite may loose its power, but then again, the sulphite and other components in the angine coolant may in fact preserve it.
Only testing will show what is happening over time.

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.

Tronds
12-22-2011, 02:41 PM
This post explains a lot about what happens when dissoving borax in glycol.

http://www.apug.org/forums/viewpost.php?p=825183

albada
12-22-2011, 02:49 PM
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
12-22-2011, 04:19 PM
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
12-22-2011, 04:24 PM
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: http://www.ams.usda.gov/AMSv1.0/getfile?dDocName=STELPRDC5067083

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
12-22-2011, 06:29 PM
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?
12-22-2011, 08:20 PM
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
12-22-2011, 11:10 PM
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
12-23-2011, 05:34 AM
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?
12-23-2011, 06:09 AM
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
12-23-2011, 09:12 AM
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
12-23-2011, 11:13 AM
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
12-23-2011, 11:31 AM
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
12-23-2011, 11:53 AM
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