Pyrocat-MC using DEA instead of TEA

Zarraboy · Nov 17, 2010

I am currently using Pyrocat-M successfully. Because of extended shelf life, i intend to start mixing Pyrocat-MC which uses glycol but where metol must be first mixed with TEA. Unfortunately TEA is not readily available in Brazil. I do have 98.5% DEA on my shelf so i was wondering if i could use it instead of TEA for the initial slurry.

Gerald C Koch · Nov 17, 2010

DEA is more basic than TEA and I would expect it to throw off the pH of the resulting developer.

Relayer · Nov 18, 2010

its work with DEA and can be made as single solution concentrate. see my post (there was a url link here which no longer exists)

Pyrocat-PC-DEA

DEA 100ml
p-aminophenol - 0.5g
ascorbic acid - 0.4g
pyrocatechin - 5g

working dilution 1:100

Pyrocat-HDC-DEA

DEA 100ml
Phenidone - 0.25g
ascorbic acid - 0.4g
pyrocatechin - 5g

working dilution 1:100

dev.time same or 10-20% more than original, because diluted DEA have slightly less pH that original "carbonate" part B (11 instead 11.5)

Zarraboy · Nov 18, 2010

Relayer, i was actually referring to the Pyrocat-Metol version because i like the extra accutance metol gives. Have you tried to replace Phenidone with Metol in Pyrocat-HDC-DEA? How long will it last in a full stoppered bottle?

Relayer · Nov 18, 2010

Zarraboy said:
Relayer, i was actually referring to the Pyrocat-Metol version because i like the extra accutance metol gives. Have you tried to replace Phenidone with Metol in Pyrocat-HDC-DEA? How long will it last in a full stoppered bottle?

Pyrocat-MC-DEA

DEA 100ml
metol - 0.25g
ascorbic acid - 0.4g
pyrocatechin - 5g

working dilution 1:100

Zarraboy said:
How long will it last in a full stoppered bottle?

really you don't need to keep it as "full bottle". because DEA is organic solvent like TEA - oxygen isn't so important as for water-based solution. but other tips - we need to protect TEA/DEA concentrates from water. this is very important. otherwise concentrate is dead very quickly

Zarraboy · Nov 18, 2010

Great. Have you actually tried this one? How does it compare to Pyrocat-M and Pyrocat-HD?

Zarraboy · Nov 18, 2010

I see you posted the Metol = Phenidone, weight by weight. Is that correct?

Relayer · Nov 18, 2010

Zarraboy said:
I see you posted the Metol = Phenidone, weight by weight. Is that correct?

all proportions same as in original formulas from here

Relayer · Nov 18, 2010

Zarraboy said:
Great. Have you actually tried this one? How does it compare to Pyrocat-M and Pyrocat-HD?

no, I just only compare Pyrocat-PC with Pyrocat-PC-DEA and found that result is the same ((there was a url link here which no longer exists)). I think that other solution with DEA will be also produce result near to the original formula.

Pyrocat-MC using DEA instead of TEA

Privacy & Transparency

Privacy & Transparency