KODACHROME DYE COUPLERS FROM US PATENT 3,658,525
The developing process which is revealed in US patent 3658525, (Bent and Mowrey inventors), discloses enough detailed information that a chemist skilled in photographic processing could use it to duplicate, basically, the method that Kodak used to process Kodachrome color film. A specific example is given on columns 9-11 of the patent, while other parts of the developing compositions are given earlier. Apparently the cyan and yellow developers use CD-4 in the patent, although a different developer--CD-3?--was used in practice.
The specific example in columns 9-11 states exactly the chemical used for the cyan coupler. This is:
CYAN COUPLER FOR KODACHROME FROM US PATENT 3658535
I-Hydroxy-N-(2-acetamidophenethyl)-2-naphthamide.
However, for the other two couplers the example only states the chemical properties which the yellow and the magenta couplers should have. It does not name the couplers exactly. The yellow coupler is of a class of chemicals called an alpha-pivalyl-acetanilide. In the list of sources for couplers given in the Kodachrome patent 3658525 (which appears in column 5), none of the sources listed shows a yellow coupler which is an alpha-pivalyl-acetanilide. However, in a patent about yellow dye couplers granted in 1966, US patent 3265505 (Weissberger and Kibler inventors) there are three dye couplers which are alpha-pivalyl-acetanilides, and which are also diffusible into an emulsion. These ought to be suitable for Kodachrome processing. They are called coupler 18, coupler 20 and coupler 25.
YELLOW COUPLERS FOR KODACHROME FROM US PATENT 3265505
Coupler 18, alpha-Pivalyl-3,5-dicarbomethoxyacetanilide;
Coupler 20, alpha-Pivaly1-alpha - (3 tetradecylcarbamylphenylthio)-3,5-di-carbomethoxyacetanilide.
Coupler 25, Alpha-pivalyl-alpha-( 3-octadecylcarbamyl phenylthio)-4-chlorosulfonylacetanilide
The Kodachrome example process in column 11 says the magenta coupler is a 5-pyrazolone coupler of U.S. Pat. No. 3,152,896. There are eight of these:
MAGENTA COUPLERS FOR KODACHROME FROM US PATENT 3152896
(1) 1 - (2,4,6 — trichlorophenyl) - 3 - (4 - methylsulfo~nylanilino) - 5 - pyrazolone
(2) 1- (2,4,K6-trichlorophenyl) —3- (4-cyanoanilino) —5-pyrazolone
(3) 1- ( 2,4,6-trichlorophenyl ) -3-( 3-cyanoanilino ) —5-pyrazolone
(4) 1- (Z,4,6-trichlorophenyl) —3-(2-chloro-5-cyanoanilino) —5-pyrazolone
(5) 1- (2,4,‘6-trichlorophenyl) —3- ( 3-nitroanilino) —5-pyrazolone
(6) l- (2,4,6-trichlorophenyl) —3- (2,4-dichloroanilino) —5 pyrazolone
(7) 1- (2,6-dichloro-4-nitrophenyl) —3- (2,4-dichloroanilino)—‘5-pyrazolone .
(8) 1- (2,6-dichloro-4-cyanophenyl ) —3- (2,4-dichloroani lino) —g 5-pyraz0l0ne
Here is the structure for magenta coupler (1)
View attachment 171361