Jack S Richards

US Patent:

43918964, Jul 5, 1983

Filed:

Sep 20, 1978

Appl. No.:

5/944113

Inventors:

Thomas O. Maier - Rochester NY
Jack L. Richards - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G03C 140
G03C 110
G03C 554

US Classification:

430223

Abstract:

Curve shape control, especially for lower scale contrast, of a photographic element is achieved by employing with the silver halide emulsion layer two nondiffusible redox dye-releasing compounds of different relative reactivities, the reactivity of the compound which is more reactive being at least 1. 5 times the reactivity of the compound which is less reactive. Preferred compounds are ballasted sulfonamido compounds, each of which has a color-providing moiety attached thereto through a sulfonamido group which is alkali-cleavable upon oxidation. Preferred more reactive sulfonamido compounds have a N,N-disubstituted carbamoyl ballast group. The color-providing moieties can be (1) transferred imagewise to an image-receiving layer to provide a useful image, or (2) can be merely diffused out of the element to provide a retained image therein which can be treated to form a color transparency or a motion picture film.