View Full Version : Sulfonic Acid Dye for 2 Color Kodak Process

Mustafa Umut Sarac
06-30-2010, 10:22 PM

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


Photo Engineer
06-30-2010, 10:25 PM
Most dyes at that time were based on sulfonic acids and they were easy to incorporate into photographic materials.


Mustafa Umut Sarac
06-30-2010, 10:30 PM
I found that at 1921 , sulfonic acid is patented as a low light condition latent image developer.
Patent number is 1370896

Mustafa Umut Sarac
06-30-2010, 10:36 PM
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 ?

Photo Engineer
06-30-2010, 10:38 PM
No. This is so obsolete it is virtually unknown. Ciba uses Sulfonic acid based Azo dyes for Ilfochrome. You might try them.


Mustafa Umut Sarac
06-30-2010, 11:57 PM
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.

Mustafa Umut Sarac
07-01-2010, 03:06 AM
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.

Photo Engineer
07-01-2010, 09:42 AM
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.


Mustafa Umut Sarac
07-01-2010, 10:52 AM
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.

Photo Engineer
07-01-2010, 11:07 AM

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!


Mustafa Umut Sarac
07-01-2010, 11:44 AM
Ron ,

and mordants increase the color density . I watched a program at BBC about mordant making from seashells at the shores of England. Flat bottomed boats come to the shore and sit to the ground after tidal wave goes and horse carriages carry these shells to the ships. It was one of the biggest industry in England until the 1900s. I think seashell have calcium aluminum inside and oxidised at big burning pits.
Yes , it was alum , alum trade !
Thank you for the tip .

Mustafa Umut Sarac
07-27-2010, 03:45 PM
I contacted with Eastman House , waited 4 weeks , directed to Motion Film Dep. and directed to RIT Rare books librarian and directed to retired Kodak Research Lab. member.

He says he doesnt believe to salts of sulfonic acid dye theory but inorganic pigments. He says he believes to ferro or ferri cyanides for green but no idea about Red.

He supports Magnesium Alum theory.

He says Capstaff changed the direction to cyan , magenta colors later. ps. I posted his patent numbers.

He says they were applying a bleach to BW Slide and than replace silver with pigments.

He doesnt believe to glue two films together idea.


Photo Engineer
07-27-2010, 05:30 PM
IDK who you talked to from Kodak, but he is correct. The pigment replacement was difficult AFAIK (see my other post) and also AFAIK was never commercialized. Instead, Dye Transfer was developed.

At the end of our Azo dye work, we were using Azo dyes that formed complexes with Nickel to form very stable dyes on mordants.


Mustafa Umut Sarac
11-25-2010, 01:56 PM
look at below for sulfonic acid R G colors formulas.