Patent ID: 7429447

Claim:
An image forming method using a photothermographic material comprising, on at least one side of a support, an image forming layer comprising at least a photosensitive silver halide, a non-photosensitive silver salt of a fatty acid, a reducing agent, and a binder, wherein the photothermographic material comprises an acetylene compound represented by the following formula (II) or a salt thereof: wherein R 2 represents a substituted or unsubstituted alkyl group, aryl group, or heterocyclic group; R 3 represents a hydrogen atom or a substituent substituting for a hydrogen atom on a benzene ring; n1 represents an integer of 1; and n2 represents an integer of from 0 to 4; wherein the image forming method comprises: 1) imagewise exposing the photothermographic material with lights to record a latent image on the photothermographic material; and 2) thermally developing the photothermographic material at a temperature of 107° C. to 140° C. to convert the latent image into a visible image by thermal development.