Pyrazolo 1,5 a benzimidazole photographic color couplers
AssigneeEastman Kodak Company
InventorsMichael William Crawley, Andrew William Gibson, Paul Louis Reginald Stanley, Hugh Martin Williamson
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Abstract
Novel non-diffusible pyrazolo-1,5-a! benzimidazole color couplers having an alkylene-, oxyalkylene- or arylene- thio coupling-off group, substituted with a carboxylic acid or dialkylamino group, have dye-forming and/or bleach-accelerating properties. The couplers are generally associated with a silver halide emulsion layer coated on a support to form a single color or multi-color photographic element.
Claims9
A photographic material comprising a support, a silver halide emulsion layer and, associated therewith, a coupler which is a non-diffusible pyrazolo-1,5-a!benzimidazole color coupler which has the general formula:
- ##STR15## wherein R.sup.1 to R.sup.5 are each hydrogen or a substituent, and wherein at least one of R.sup.1 to R.sup.5 contains a ballast group capable of rendering the coupler non-diffusible in photographic layers;
- and
- R.sup.8 represents a substituted or unsubstituted alkylene group or CHR wherein R is a substituted or unsubstituted alkyl group.
Dependencies are inferred from the claim text.