Post-processsing stabilization of photothermographic emulsions
AssigneeMinnesota Mining and Manufacturing Company
InventorsLarry R. Krepski, Kumars Sakizadeh, Sharon M. Simpson, David R. Whitcomb
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Abstract
The post-processing stability of silver halide photothermographic emulsions is enhanced by the presence of stabilizing amounts of certain azlactones.
Claims27
A photothermographic emulsion comprising a silver halide, silver source material, reducing agent for silver ion, binder and a post-processing stabilizing amount of an azlactone represented by any one of the formulae:
- ##STR9## wherein A represents a residue of post-processing stabilizer compound in which a hydrogen atom of the post-processing stabilizer compound has been replaced by ##STR10## wherein R.sup.1 is hydrogen, methyl or aryl, R.sup.2 and R.sup.3 are independently hydrogen or methyl and with the proviso that R.sup.1 can represent an aryl group only when R.sup.2 and R.sup.3 are hydrogen;
- R.sup.4 and R.sup.5 independently represent an alkyl group, a cyclo alkyl group, an aryl group or R.sup.4 and R.sup.5 taken together with the carbon atom to which they are joined form a ring of 4 to 12 atoms;
- R.sup.6 and R.sup.7 are independently hydrogen or lower alkyl;
- R.sup.8 is any organic group selected from the group consisting of alkyl groups of 1 to 20 carbon atoms, aryl groups and heterocyclic groups with up to 7 ring atoms;
- and
- n is 0 or 1.
A photothermographic emulsion comprising a photographic silver halide, silver source material, reducing agent for silver ion, binder and a post-processing stabilizing amount of an azlactone represented by any one of the formulae:
- ##STR11## wherein A represents a residue of a post-processing stabilizer compound in which a hydrogen atom of the post-processing stabilizer compound has been replaced by ##STR12## wherein R.sup.1 is selected from hydrogen, methyl or aryl, R.sup.2 and R.sup.3 are independently hydrogen or methyl and with the proviso that R.sup.1 can represent an aryl group only when R.sup.2 and R.sup.3 are hydrogen;
- R.sup.4 and R.sup.5 independently represent an alkyl group, a cycloalkyl group, an aryl group or R.sup.4 and R.sup.5 taken together with the carbon atom to which they are joined from a ring of 4 to 12 atoms;
- R.sup.6 and R.sup.7 are independently hydrogen or lower alkyl of 1 to 4 carbon atoms;
- R.sup.8 is any organic group and
- n is 0 or 1.
A photothermographic emulsion comprising a photographic silver halide, silver source material, reducing agent for silver ion, binder and a post-processing stabilizing amount of an azlactone represented by any one of the formulae:
- ##STR13## wherein R.sup.1 is hydrogen, methyl, or aryl, R.sup.2 and R.sup.3 are independently hydrogen or methyl and with the proviso that R.sup.1 can represent an aryl group only when R.sup.2 and R.sup.3 are hydrogen;
- R.sup.4 and R.sup.5 independently represent an alkyl group, a cyclo alkyl group, an aryl group or R.sup.4 and R.sup.5 taken together with the carbon atom to which they are joined form a ring of 4 to 12 atoms;
- R.sup.6 and R.sup.7 are independently hydrogen or lower alkyl;
- R.sup.8 is any organic group selected from the group consisting of alkyl groups, aryl groups and heterocyclic groups;
- and
- n is 0 or 1.
Dependencies are inferred from the claim text.