[alt-photo] 1922 Kodak Sulfonic Acid Dye

[Mustafa Umut Sarac]

I am researching Kodak 1922 - 1927 Two Color Process.
There are two color dyes applied to either sides of the film.
As patents described Brownish Yellow and Green.
These two gives excellent , charming skin colors.

I looked to the end of 19th century to 1930s patents and learned that these
dyes are salt of sulfonic acid.
I need exact names. Anyone knows them ?

thank you ,

Mustafa Umut Sarac

Istanbul