Photographic contrast enhancers
AssigneeMinnesota Mining and Manufacturing Company
InventorsJohn R. Boon, Gregory J. Wagner
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Abstract
As silver is the most expensive individual component in photographic film, it is desirable to reduce the quantities of silver in such materials. The addition of a certain class of phenolic derivatives has been found to enhance the contrast generated by dyes in color photographic emulsions. Emulsions containing these phenolic compounds can use less silver and produce the same optical density as emulsions with higher silver concentrations.
Claims5
A color photographic silver halide emulsion in a layer comprising a hydrophilic colloid, silver halide, and an oil droplet dispersion of a anilino-5-pyrazolone color photographic coupler, wherein said layer also contains an effective amount of a contrast enhancer of the formula:
- ##STR8## wherein R is an alkyl group of 4 to 20 carbon atoms.
Dependencies are inferred from the claim text.