| 摘要 |
<p>The invention provides a photographic element comprising a support bearing a light-sensitive photographic silver halide layer having associated therewith a masking coupler comprising: (1) a parent group containing a -1-phenyl-3-anilinopyrazolin-5-one having electron-withdrawing substituents on the phenyl and anilino rings of a type and number sufficient to provide a combined Hammett sigma(para) value for such substituents of at least 1.4; (2) a coupling-off group at the 4 position of the pyrazolone of the parent group comprising an arylazo group containing on the aryl ring the following: (A) a substituent para to the azo functionality selected from hydroxyl, alkoxy, carbonamido, and sulfonamido, each unsubstituted or substituted with nonaromatic groups, and (B) "n" additional substituents selected from alkyl, alkoxy, carbonamido, and sulfonamido, unsubstituted or substituted with nonaromatic groups, where "n" is 0 to 4; wherein one of the substituents (A) or (B) contains an alkyl group of at least 8 carbon atoms, unsubstituted or substituted with nonaromatic substituents, and said substituent contains at least 70% of the saturated carbon atoms in all of the substituents (A) and (B) provided that where the substituent (A) forms a ring with a substituent (B) the entire ring will be counted as R<4> for purposes of satisfying the 70% requirement.</p> |
