Photographic elements containing a de-aggregating compound, dye-forming coupler and stabilizer

A multi-colour photographic element comprising a support bearing yellow, magenta and cyan image-dye-forming units comprising at least one blue-, green- or red-sensitive silver halide emulsion layer having associated therewith at least one yellow, magenta or cyan dye-forming coupler respectively, wherein the element comprises at least one light-sensitive silver halide emulsion layer having associated therewith in the same dispersion a de-aggregating compound of formula (I), at least one heterocyclic cyan dye-forming coupler of formula (II) and a stabilizer of formula (III):

• wherein
• the de-aggregating compound has the formula (I)
• wherein
• A is a hydrogen-bond-accepting hetero-atom or -group;
• Y is a hydrogen-bond-donating hetero-atom or -group;
• L is a linking group that is partially or wholly conjugated with A and linked to A by a carbon atom;
• n is 1, 2 or 3 hydrogen-bond-containing moieties;
• and
• (B) comprises the remaining atoms for completion of an unsubstituted or substituted heterocyclic ring or ring system containing the hydrogen bond-accepting hetero-atom or -group, which may contain one or more other heteroatoms selected from nitrogen, oxygen and sulfur;
• and
• wherein
• the heterocyclic cyan dye-forming coupler has the formula (II):
• wherein
• R1 is hydrogen or a substituent;
• Rc is a substituent;
• and
• q is 0 to 4;
• Za represents the atoms necessary to complete an unsubstituted or substituted 5- to 10-membered heterocyclic ring system which may contain one or more other heteroatoms selected from nitrogen, oxygen and sulfur;
• providing that each Rc is attached to a carbon atom of the ring;
• and
• X is selected from hydrogen or halogen or a group which is separable by the reaction of coupler with an oxidized colour developing agent;
• and
• wherein
• the stabilizer of formula (III) has the formula
• wherein
• R5 is an electron-donating group;
• R6 is a substituent;
• each R7 is an independently selected substituent;
• or
• one of R5 and R6 may join with R7 to form an unsubstituted or substituted 5- to 10-membered ring system which may contain one or more heteroatoms selected from nitrogen, oxygen and sulfur;
• and
• s is 0 to 4;
• provided that
• (a) when one of R5 and R6 is a hydroxy group then the other may not be an arylsulfonamido or arylsulfamoyl substituent, and
• (b) at least one of R5, R6 and R7 contains a ballast group comprising at least 8 carbon atoms.

A process of forming an image in a photographic element after the element has been imagewise exposed to light, comprising contacting the element with a colour developing agent, wherein the element comprising at least one light-sensitive silver halide emulsion layer having associated therewith in the same dispersion a de-aggregating compound of formula (I), at least one heterocyclic cyan dye-forming coupler of formula (II) and a stabilizer of formula (III):

• wherein
• the de-aggregating compound has the formula (I)
• wherein
• A is a hydrogen-bond-accepting hetero-atom or -group;
• Y is a hydrogen-bond-donating hetero-atom or -group;
• L is a linking group that is partially or wholly conjugated with A and linked to A by a carbon atom;
• n is 1, 2 or 3 hydrogen-bond-containing moieties;
• and
• (B) comprises the remaining atoms for completion of an unsubstituted or substituted heterocyclic ring or ring system containing the hydrogen bond-accepting hetero-atom or -group, which may contain one or more other heteroatoms selected from nitrogen, oxygen and sulfur;
• and
• wherein
• the heterocyclic cyan dye-forming coupler has the formula (II):
• wherein
• R1 is hydrogen or a substituent;
• Rc is a substituent;
• and
• q is 0 to 4;
• Za represents the atoms necessary to complete an unsubstituted or substituted 5- to 10-membered heterocyclic ring system which may contain one or more other heteroatoms selected from nitrogen, oxygen and sulfur;
• providing that each Rc is attached to a carbon atom of the ring;
• and
• X is selected from hydrogen or halogen or a group which is separable by the reaction of coupler with an oxidized colour developing agent;
• and
• wherein
• the stabilizer of formula (III) has the formula
• wherein
• R5 is an electron-donating group;
• R6 is a substituent;
• each R7 is an independently selected substituent;
• or
• one of R5 and R6 may join with R7 to form an unsubstituted or substituted 5- to 10-membered ring system which may contain one or more heteroatoms selected from nitrogen, oxygen and sulfur;
• and
• s is 0 to 4;
• provided that
• (a) when one of R5 and R6 is a hydroxy group then the other may not be an arylsulfonamido or arylsulfamoyl substituent, and
• (b) at least one of R5, R6 and R7 contains a ballast group comprising at least 8 carbon atoms.