| abstract |
An silver halide photothermographic light sensitive material comprising a support having thereon a undercoating layer and a photographic light-sensitive layer containing a light-sensitive silver halide, and organic silver salt, a reducing agent and a binder, wherein the undercoating layer contains fine particles having a mean primary particle size of 0.01 to 1.6 mum and satisfying the following equation,wherein r1 and r2 are respectively an inscribed circle radius and a circumscribed circle radius of each of projected images of the fine particles obtained by a microscope, and (r2/r1) is an average value of r2/r1 of projected images of 500 fine particles randomly selected from the whole fine particles. |