Silver salt photothermographic dry imaging material and image forming method by use thereof

An image forming method comprising:

• subjecting a photothermographic material comprising on at least one side of a support a light-sensitive layer containing an organic silver salt, photosensitive silver halide grains, a binder and a reducing agent for silver ions and a light-insensitive layer to imagewise exposure and
• subjecting the photothermographic material to thermal development to form an image,
• wherein a total thickness of the light-sensitive layer and the light-insensitive layer is from 10 to 20 μm and at least one of the light-sensitive layer and the light-insensitive layer contains a compound capable of forming a dye image upon thermal development;
• and wherein the exposure and the thermal development are performed by using a laser imager, the laser imager comprises a developing section having a path length (1) and a cooling section having a path length (2), a ratio of the path length (2) to the path length (1) is not more than 1.5, and the cooling section is provided downstream from the developing section and conveys the photothermographic material sent from the developing section while cooling the photothermographic material.