Patent ID: 7462445

Claim:
An image forming method of a photothermographic material comprising on one side of a support a light-sensitive layer containing an organic silver salt, silver halide grains, a binder and a reducing agent and a light-insensitive layer and on the other side of the support a back coating layer by using a thermal processor, the method comprising the steps of: subjecting the photothermographic material to imagewise exposure and subjecting the exposed photothermographic material to thermal development to form an image, wherein the thermal processor includes a transport system in which a feed roller is disposed with being in contact with a bundle of stacked film sheets of the photothermographic material so as to feed an uppermost film sheet of the bundle of film sheets by rotation of the feed roller to subject the fed film sheet to the exposure and the thermal development; the light-insensitive layer or the back coating layer contains a lubricant having a mass average molecular weight of 550 or more.