C41 Formulas

fdonadio · Nov 28, 2016

Photo Engineer said:
Flavio, I have published the EK process directions time after time. Sorry. As for the solutions I published, they are supposed to be one-shot.

All right, Ron. I'll be searching the forums.

Thanks for the help.

Cheers,
Flavio

LFGuy · Nov 28, 2016

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fdonadio · Nov 29, 2016

Thanks, LFGuy!

fdonadio · Dec 4, 2016

PE,

I'm sourcing all the chemicals necessary and I am having a hard time with 1,3-propanediaminetetraacetic acid. Searching through Google, I've found out that it's also called (among a long list of names) 1,3-Diaminopropane-N,N,N′,N′-tetraacetic acid and the CAS # would be 1939-36-2.

Are there two compounds really the same thing?

Cheers,
Flavio

Photo Engineer · Dec 4, 2016

Yep, the same thing. It is a chelating agent similar to EDTA.

PE

fdonadio · Dec 4, 2016

Photo Engineer said:
Yep, the same thing. It is a chelating agent similar to EDTA.

I've just found it's also called "Kodak Chelating Agent No. 1".

Thanks, Ron.

Cheers,
Flavio

Rudeofus · Dec 5, 2016

If you want to follow the bleach formula PE posted to the letter, you need two chelating agents: 1,3-Diaminopropane-N,N,N′,N′-Tetraacetic Acid with CAS # 1939-36-2, and 1,3-Diamino-2-propanol-N,N,N′,N′-Tetraacetic Acid with CAS # 3148-72-9.

fdonadio · Dec 5, 2016

Rudeofus said:
If you want to follow the bleach formula PE posted to the letter, you need two chelating agents: 1,3-Diaminopropane-N,N,N′,N′-Tetraacetic Acid with CAS # 1939-36-2, and 1,3-Diamino-2-propanol-N,N,N′,N′-Tetraacetic Acid with CAS # 3148-72-9.

Thanks, Rudi!

I did a lot of research yesterday and found the same CAS numbers. It's all in a spreadsheet right now.

I'm getting a quote from Sigma-Aldrich today. Wish me luck!

Cheers,
Flávio

Rudeofus · Dec 5, 2016

fdonadio said:
I'm getting a quote from Sigma-Aldrich today. Wish me luck!

You'll need lots of luck, because the second compound is hideously expensive at Sigma Aldrich. Unless you find a cheaper source, or consent to use plain PDTA instead, you'd be cheaper having Kodak Bleach III shipped from Mars.

fdonadio · Dec 5, 2016

Rudeofus said:
You'll need lots of luck, because the second compound is hideously expensive at Sigma Aldrich. Unless you find a cheaper source, or consent to use plain PDTA instead, you'd be cheaper having Kodak Bleach III shipped from Mars.

Yea, Sigma-Aldrich has the best chemical grades, but the price is, sometimes, outrageous.

They bought a small company here in Brazil, called Vetec, a couple of years ago and are getting rid of their stock at incredible prices. The chemicals are lower grade, but I guess they would still be good for (some) photo applications. I have used their products with no problems so far.

Kodak-Alaris and FujiFilm have minimum order requirements in Brazil (around $1000 USD) and I am not currently able to spend all of that. I wish Santa dropped me a suitcase full of money! Dreaming is still free, though.

Cheers,
Flavio

flavio81 · Dec 5, 2016

Ron, thank you VERY much for this thread. Again, you delivered the goods.

Good luck Rudeofus!!

Photo Engineer · Dec 5, 2016

Well, I hope I did.

You know, you can use the original bleach with longer bleach times. It uses Ammonium FeEDTA instead. It is at pH 6.5 but otherwise is pretty much the same.

PE

Photo Engineer · Dec 5, 2016

Flavio, I hope you are aware that this is one of 3 formulas I have for C41. I tried and thanks for the comment, but I might be off in some of this.

PE

kb3lms · Dec 5, 2016

It uses Ammonium FeEDTA instead.

Does anyone have a source for Ammonium FeEDTA? Is this something you can still purchase or do you have to make it? Artcraft had it at one time but they haven't listed it for some time.

-- Jason

Photo Engineer · Dec 5, 2016

The Formulary used to sell it, but you can make it from EDTA + 28% Ammonium Hydroxide + FeCl3 (Ferric Chloride). Just mix them in the ratio of 1 Mole, 4 Moles and 1 Mole and add a 10% excess of EDTA. And, use caution. The 28% AH is nasty stuff. I used to do this all the time before the manufacturing line for the salt was up and running.

PE

Rudeofus · Dec 6, 2016

Formulary doesn't sell EDTA free acid either, only disodium and tetrasodium version, and neither of the two can be used directly for making Ammonium Ferric EDTA. You can make EDTA free acid from EDTA Disodium Salt by dissolving as much as possible in a liter of water, then adding a strong acid like Sulfuric Acid or Hydrochloric Acid. There is a chance that Amidosulfonic Acid or Sodium Bisulfate also work, but I would not expect Citric Acid or Acetic Acid to work. As long as the acid is strong enough, EDTA free acid will precipitate, because it's barely water soluble. Add acid ling enough to precipitate all the EDTA, then filter and wash the precipitate. After the precipitate is dry, which takes a few days, you can use it as EDTA free acid.

That's how I made my E6 bleach in the last couple of months - it works.

PS: If that's too much hassle, you can order Ammonium Ferric EDTA 50% concentrate from Fototechnik Suvatlar.

PPS: Ammonium Ferric EDTA based bleaches are extremely weak and take a long time. Most commercial Ammonium Ferric EDTA based bleaches contain a bleach accelerator, either 1-Thioglycerol or Mercaptotriazol. You can get the latter from Fototechnik Suvatlar, and of course from all the professional chem suppliers. Use it at 0.1 g/l, if you use more, it will slow down the bleach!

macandal · Dec 20, 2016

Why the two different Bleach recipes in posts #1 and #2?

Thanks for this.

fdonadio · Dec 20, 2016

macandal said:
Why the two different Bleach recipes in posts #1 and #2?

Something went wrong when PE first posted. The recipe that says "bleach" in that post is, in fact, the developer. PE tried to replace the file in the first post, but it didn't work.

Don't use that; use the second post recipe, which is the correct one.

Cheers,
Flavio

macandal · Dec 20, 2016

Thank you.

fdonadio said:
Don't use that; use the second post recipe, which is the correct one.

Cheers,
Flavio

Thank you.

macandal · Dec 20, 2016

Forgive me but I have another question, if I can't get Kodak Color Developing Agent CD-4 that the developer calls for, how do I get the chemicals to make it? What are the chemicals? (Is it that long, unpronounceable name?)

Thanks.

Photo Engineer · Dec 20, 2016

CD4 is the long name given there. It is not an "across the counter" item. You have to get it from specialty chemical houses.

PE

macandal · Dec 20, 2016

Photo Engineer said:
CD4 is the long name given there. It is not an "across the counter" item. You have to get it from specialty chemical houses.

PE

Thanks.

So, {2-[(4-amino-3-methylphenyl) ethylamino]ethanol sulfate} = CD-4?

Again, thank you.

dE fENDER · Dec 20, 2016

macandal said:
Forgive me but I have another question, if I can't get Kodak Color Developing Agent CD-4 that the developer calls for, how do I get the chemicals to make it? What are the chemicals? (Is it that long, unpronounceable name?)

Thanks.

It's easy to get the chemicals and begin to make CD-4 at kitchen, but you will die in the middle of the process from oxirane. Better to order it at artcraftchemicals, for example.

jsmithphoto1 · Dec 20, 2016

dE fENDER said:
It's easy to get the chemicals and begin to make CD-4 at kitchen, but you will die in the middle of the process from oxirane. Better to order it at artcraftchemicals, for example.

Yup yup. Artcraft sells it! I highly recommend ordering from them!

Photo Engineer · Dec 20, 2016

macandal said:
Thanks.

So, {2-[(4-amino-3-methylphenyl) ethylamino]ethanol sulfate} = CD-4?

Again, thank you.

There are several ways to write this chemical name but yes, this is correct.

It is also N-Ethyl, N-Hydroxy ethyl, 3 methyl para phenylene diamine sulfate - with extra spaces for clarity. Which is just another name.

PE

C41 Formulas

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