Photographic silver halide materials
AssigneeEastman Kodak Company
InventorsRobert E. Booms, Colin Holstead
Life of this patent
Estimating the term…
Abstract
Granularity of silver halide photographic materials is reduced by employing a coupler which yields a dye of such mobility that controlled image smearing occurs.
Claims14
A silver halide photographic element comprising at least one silver halide emulsion layer and nondiffusible dye-forming couplers associated with the layer or layers wherein the nondiffusible dye-forming couplers comprise a first nondiffusible dye-forming coupler which, upon reaction with oxidized color developing agent, yields a nondiffusible first dye and a second, different, nondiffusible dye-forming coupler which, upon reaction with oxidized color developing agent, yields a second dye of such mobility that said second dye in combination with said first dye produces controlled image smearing in said photographic element, said second coupler yielding a dye of limited mobility and having the structure:
- ##STR14## wherein:
- COUP is a dye-forming coupler moiety, the asterisk (*) denoting the coupling position thereof;
- MAIN BALLAST is a group, attached to the coupling position of COUP and detachable therefrom by means of reaction of COUP with oxidized color developing agent, which is of such size and configuration as to render the coupler nondiffusible;
- and
- SECONDARY BALLAST is a group, attached to a noncoupling position of COUP, which is of such size and configuration that the dye formed by coupling of COUP with oxidized color developing agent is slightly mobile.
A silver halide photographic element comprising at least one silver halide emulsion layer and nondiffusible dye-forming couplers associated with the layer or layers wherein the nondiffusible dye-forming couplers comprise a first nondiffusible dye-forming coupler which, upon reaction with oxidized color developing agent, yields a nondiffusible first dye and a second, different, nondiffusible dye-forming coupler which, upon reaction with oxidized color developing agent, yields a second dye of such mobility that said second dye in combination with said first dye produces controlled image smearing in said photographic element, said second coupler yielding a diffusible dye and having the structure:
- ##STR15## COUP is a dye-forming coupler moiety, the asterisk (*) denoting the coupling position thereof;
- BALLAST is a group, attached to the coupling position of COUP and detachable therefrom by means of reaction of COUP with oxidized color developing agent, which is of such size and configuration as to render the coupler nondiffusible;
- and
- SOL is a solubilizing substituent, attached to a non-coupling position of COUP, which renders the dye formed by coupling of COUP with oxidized color developing agent diffusible in the alkaline environment present during photographic processing and, associated with the layer containing the second coupler, a mordant which immobilizes the diffusible dye.
Dependencies are inferred from the claim text.