Patent ID: 7105283

Claim:
A black and white photothermographic material comprising, on at least one surface of a support, an image forming layer containing at least a photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent for silver ions, and a binder, wherein: 1) 70% or more of a total projected area of the photosensitive silver halide is occupied by tabular grains having an aspect ratio of 2.5 or more, a mean projected area equivalent diameter of 0.5 μm to 8 μm, and a mean grain thickness of 0.02 μm to 0.2 μm, and 2) a ratio of a number of sites forming a development initiation point on a corner portion or a fringe portion of the photosensitive silver halide grain to all development initiation points is 50% or more.