Abstract: Disclosed is a photographic element comprising a light-sensitive silver halide emulsion layer having associated therewith a coupler based on a 1-aryl-3-arylpyrazol-5-one or a 1-aryl-3-alkylpyrazol-5-one ring and represented by formula I: ##STR1## wherein: X represents an aryl, alkyl, alkylamino, or arylamino group;Y can be carbon or sulfur; in is 1 when Y is carbon and 2 when Y is sulfur;R represents a halogen or an alkyl group; and o is 0 to 4, provided that two or more R substituents may join to form one or more additional rings;Z is either (a) an aryl group represented as Ar.sup.3 Q(n) where Q represents n independently selected substituents bonded to the Ar.sup.3 ring; and n is 0 to 5, provided that two or more Q substituents may join to form one or more additional rings or (b) an alkyl group;OAr.sup.4 is an aryloxy group; andP represents p independently selected substituents bonded to the OAr.sup.

Abstract: Disclosed is a photographic element comprising a light-sensitive silver halide emulsion layer having associated therewith a pyrazol-5-one coupler bearing a 4-aryloxy coupling-off group containing a group capable of releasing a photographically useful group (PUG) wherein:(1) the pyrazol-5-one ring contains a 1-aryl substituent which in turn contains, in a position ortho to the bond linking it to the pyrazolone ring, a secondary carbonamido group or a secondary sulfonamido group;(2) the pyrazol-5-one ring contains either (a) a 3-aryl substituent which in turn contains substituents for which the sum of the Hammett's .sigma. constant values is -0.3 or higher or (b) a 3-alkyl substituent; and(3) the 4-aryloxy coupling-off group:(a) contains ring substituents selected so that the sum of the Hammett's .sigma. constant values for all substituents on the phenoxy ring is at least 0.