US Patent 7439011 Photothermographic material

A photothermographic material including, on one side of a support, an image forming layer containing at least a photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent and a binder, and, on the other side of the support, a non-photosensitive back side layer. The total quantity of an alkaline earth metal contained in the non-photosensitive back side layer is 1×10−5 mol/m2 to 1×10−3 mol/m2.