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If you look my thread , you find 1910s two color kodak film patents and it says salt of sulfonic acid dye for green and orange.
Patents are for skilled people and I want to learn more from you.
Thank you ,
Mustafa Umut Sarac
Istanbul
Most dyes at that time were based on sulfonic acids and they were easy to incorporate into photographic materials.
PE
I found that at 1921 , sulfonic acid is patented as a low light condition latent image developer.
Patent number is 1370896
Ron , is there any contact person you know from Kodak who will be able to give me the correct recipe of green and brownish yellow sulfonic acid dyes preparation ?
No. This is so obsolete it is virtually unknown. Ciba uses Sulfonic acid based Azo dyes for Ilfochrome. You might try them.
PE
Ron , I searched the internet and there are tens may be hundreds of sulfonic acid green formulas.
Is it possible to reach , buy a short strip of these green , orange films and analysis ? Its single chemical not a soup like a developer . But is there any this kind of antiques dealers you know ? I ask everyone.
I learned that series of dye chemistry books published by kodak starting from 1920. I have 1940 book and found interesting chemicals related to sulfonates.
I need 1920 book. I think it will solve all the problems. I asked to Eastman House also.
Sulfonates are the name of salts of sulfonic acids.
Most all azo dyes manufactured today for use in water solution are Sulfonates. I have no other information on the spectra or use of them in film, as such use was restricted to either Dye Transfer or Ciba/Ilfochrome since about 1940.
PE
1196080
Filing day is 1914 and its about color photography , two color process and sulfonates.
It is as you said the sulfonate formula might be water soluble because it says rinse the film with water after applying dyes. I will look to archive org for 1920 book.
Mustafa;
Often, mordants were used to hold sulfonic acid dyes in place. Sometimes Calcium Aluminum or Magnesium salts were used as a mordant but in some cases, even gelatin itself served as a mordant. This is the same way a sulfonic acid dye is held fast in cloth!
PE