Some speculations about flexicolor C41B

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(1)
I tested its density.
part A 1.412
part B 1.097
part C 1.097
It can be inferred from this,the substance in it is:
A about 42-44g,It contains K2CO3,KOH,KBr(or NaBr),and something anti Cal
B about 10-11g, It contains HAS
C about 10-11g ,It contains K2S2O5,CD-4

1L developer need A60.5ml B32.6ml C17.5ml start30ml，then：
K2CO3,KOH,KBr(or NaBr),and something anti Cal——about 26g
HAS——about 3.4g
K2S2O5,CD-4——about 1.8g
1L developer need CD-4 no more than 1.8g,So there must be something else,A substance that accelerates development,But it's not necessarily inside C.

Another question 1,Existence of KOH.
I added a small amount of potassium carbonate and potassium bicarbonate to the developer,keep the PH value unchanged,And the color has changed a lot,The colour turns magenta，It's like the feeling of PH value down,It shows that potassium bicarbonate neutralizes potassium hydroxide.

Another question 2,Why is part B so big capacity?if only HAS ,not need such big capacity.It must contain substances with low solubility.

(2)
There is a problem with all DIY C41 formulations.
Unable to maintain PH 10.05,and having normal,verage colors.In order to keep the shadow details,have to raise pH,then Overdevelopment of Cyan dyes,One hundred Formulas，No exceptions.
This problem is evident in Ektar100 films,Ektar100 is the only way to detect developer.The skin color of Ektar100 will turn red if the pH is too high!!

It must contain a substance used to inhibit Cyan dyes(or accelerated magenta dyes,I can't be sure).

I found hydroquinone（123-31-9） to be barely achievable, but not perfect, or just passable ...no more than 10 mg per liter

 

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A about 42-44g,It contains K2CO3,KOH,KBr(or NaBr),and something anti Cal
B about 10-11g, It contains HAS
C about 10-11g ,It contains K2S2O5,CD-4

——Sorry, I made a serious mistake.That's wrong.

 

[Rudeofus]

If you look at the Flexicolor C-41 MSDS here, densities of part C is listed as 1.10 as measured by you, but the MSDS also states 25-30% CD-4 in part C. It appears that one can not directly translate from liquid density to salt content.

 

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If you look at the Flexicolor C-41 MSDS here, densities of part C is listed as 1.10 as measured by you, but the MSDS also states 25-30% CD-4 in part C. It appears that one can not directly translate from liquid density to salt content.

thanks!
According to this parameter，in 1L developer，HAS is 9.45~11.35g，CD4 is 4.81~5.78g，HAS is very high,so it is speculated that the content of potassium hydroxide is very high.
Nitrilotriacetic acid, trisodium salt (5064-31-3),Should this is just for antiCAL？

 

[Rudeofus]

Yes, this Nitrilotriacetic acid, trisodium salt is a sequestering agent for water hardness, but also for iron and copper impurities, which can diminish working solution life. Note, that many sequestering agents also have buffering properties around pH 10, therefore it may not be trivial to replace one with another.

 

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Yes, this Nitrilotriacetic acid, trisodium salt is a sequestering agent for water hardness, but also for iron and copper impurities, which can diminish working solution life. Note, that many sequestering agents also have buffering properties around pH 10, therefore it may not be trivial to replace one with another.

MSDS certainly doesn't include everything，It doesn't explain mix part A and C turn cyan.

 

[koraks]

It doesn't explain mix part A and C turn cyan.

Part A contains the carbonate. So that does explain a lot.

 

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Part A contains the carbonate. So that does explain a lot.

CD-4 and K2S2O5 enter carbonate solution,can't turn cyan

 

[koraks]

Well, you're right in that the sulfite should render the solution virtually colorless. Unless substantial oxidation of the CD4 or the sulfite has already taken place, I suppose.