Photothermographic silver halide material and process

In a photothermographic element comprising a support bearing, in reactive association, (a) photosensitive silver halide grains and (b) an image forming combination comprising (i) an organic heavy metal salt oxidizing agent with (ii) a reducing agent for the organic heavy metal salt oxidizing agent, the improvement wherein;

• at least 50% of the projected area of the photosensitive silver halide grains is provided by thin tabular grains having an average grain thickness of less than 0.3 microns.

In a photothermographic element comprising a support bearing, in reactive association, in a poly(vinyl butyral) binder, (a) photosensitive silver halide grains and (b) and image forming combination comprising (i) an organic silver salt oxidizing agent comprising silver behenate with (ii) a phenolic reducing agent for the organic silver salt oxidizing agent, the improvement wherein;

• at least 70% of the projected area of the photographic silver halide grains is provided by thin tabular grains having an average grain diameter within the range of about 0.30 to about 0.45 .mu.m, an average grain thickness within the range of about 0.04 to about 0.05 microns and an average aspect ratio within the range of 5:1 to 15:1.

In a photothermographic composition comprising photosensitive silver halide grains and a photographic silver halide processing agent, the improvement wherein,

• at least 50% of the projected area of the photosensitive silver halide grains is provided by thin tabular grains having an average grain thickness of less than 0.3 microns.

In a photothermographic composition comprising (a) photosensitive silver halide grains and (b) an image forming combination comprising (i) an organic heavy metal salt oxidizing agent with (ii) a reducing agent for the organic heavy metal salt oxidizing agent, the improvement wherein;

• at least 50% of the projected area of the phototsensitive silver halide grains is provided by thin tabular grains having an average grain thickness of less than 0.3 microns.

In a photothermographic composition comprising, in a poly(vinyl butyral) binder, (a) photosensitive silver halide grains and (b) an image forming combination comprising (i) an organic silver salt oxidizing agent comprising silver behenate with (ii) a phenolic reducing agent for the organic silver salt oxidizing agent, the improvement wherein,

• at least 70% of the projected area of the photographic silver halide grains is provided by thin tabular grains having an average grain diameter within the range of about 0.30 to about 0.45 .mu.m, an average grain thickness within the range of about 0.04 to about 0.05 microns and an aspect ratio within the range of 5:1 to 15:1.

A process of developing an image in an exposed photothermographic element comprising a support bearing, in reactive association, (a) photosensitive silver halide grains wherein at least 50% of the projected area of the photosensitive silver halide grains is provided by thin tabular grains having an average grain thickness of less than 0.3 microns, and (b) a photosensitive silver halide processing agent, said process comprising;

• heating said element to a temperature within the range of about 90.degree. C. to about 180.degree. C. until said image is developed.

A process of developing an image in an exposed photothermographic element comprising a support bearing, in reactive association, (a) photosensitive silver halide grains wherein at least 50% of the projected area of the photosensitive silver halide grains is provided by thin tabular grains having an average grain thickness of less than 0.3 microns, and (b) an image forming combination comprising (i) an organic heavy metal salt oxidizing agent with (ii) a reducing agent for the organic heavy metal salt oxidizing agent, said process comprising;

• heating said element to a temperature within the range of about 90.degree. C. to about 180.degree. C. until said image is developed.

A process of developing an image in an exposed photothermographic element comprising a support bearing, in reactive association, in a poly(vinyl butyral) binder, (a) photosensitive silver halide grains wherein at least 70% of the projected area of the silver halide grains is provided by thin tabular grains having an average grain diameter within the range of about 0.30 to about 0.45 .mu.m, an average grain thickness within the range of about 0.04 to about 0.05 microns and an average aspect ratio within the range of 5:1 to 15:1;

• and (b) an image forming combination comprising (i) an organic silver salt oxidizing agent comprising silver behenate with (ii) a phenolic reducing agent for the organic silver salt oxidizing agent, said process comprising;
• heating said element to a temperature within the range of about 90.degree. C. to about 180.degree. C. until said image is developed.