Photothermographic material

A method for preparing a photothermographic material comprising:

• preparing a photosensitive composition containing a non-photosensitive organic silver salt, a photosensitive silver halide, a reducing agent, a binder and a cross-linking agent, and
• coating the photosensitive composition on a support, wherein the photosensitive composition further contains a compound capable of generating a labile species other than a halogen atom upon exposure to ultraviolet radiation or visible radiation, said compound is a biimidazolyl compound represented by the following formula (1) or an iodonium compound represented by the following formula (2):
• wherein R1, R2 and R3 each are an alkyl group, an alkenyl group, an alkoxy group, an aryl group, hydroxy, a halogen atom, an aryloxyl group, an alkylthio group, an arylthio group, an acyl group, a sulfonyl group, an acylamino group, sulfonylamino group, an acyloxy group, carboxy, cyano, a sulfo group, or an amino group;
• wherein Q is a group of atoms necessary to complete a 5-, 6-, or 7-membered ring, and the atoms being selected from a carbon atom, nitrogen atoms, oxygen atom and sulfur atom;
• R1, R2 and R3 each are a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, an aryl group, hydroxy, a halogen atom, an aryloxyl, an alkylthio group, an arylthio group, an acyl group, a sulfonyl group, an acylamino group, sulfonylamino group, an acyloxy group, a carboxy group, a cyano group, a sulfo group, or an amino group, provided that R1, R2 and R3 may be bonded with each other to form a ring;
• R4 is a carboxylate group or O−;
• W is 0 or 1, provided that when R3 is a sulfo group or a carboxy group, W is 0 and R4 is O−;
• X− is an anionic counter ion.