Patent ID: 7250249

Claim:
A black and white photothermographic material comprising, on at least one side of a support, an image forming layer comprising at least a photosensitive silver halide, a silver salt of an aliphatic carboxylic acid having 10 to 30 carbon atoms, a reducing agent for silver ions, and a binder of which 50% by weight or more is a polymer latex containing a monomer component represented by the following formula (M) in a range of from 10% by weight to 70% by weight: CH 2 ═CR 01 —CR 02 ═CH 2 Formula (M) wherein R 01 and R 02 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom, or a cyano group, wherein the black and white photothermographic material comprises a compound represented by the following formula (I) as the reducing agent, and further comprises an auxiliary reducing agent represented by the following formula (R) and a coupler which is represented by the following formula (BC-1) and performs a coupling reaction with an oxidation product of the compound represented by formula (I) to form a dye: wherein R 1 , R 2 , R 3 and R 4 each independently represent a hydrogen atom or a substituent; R 5 and R 6 each independently represent an alkyl group, an aryl group, a heterocyclic group, an acyl group, or a sulfonyl group; members in at least one combination of R 1 and R 2 , R 3 and R 4 , R 5 and R 6 , R 2 and R 5 , and R 4 and R 6 may bond to each other to form a 5-, 6-, or 7-membered ring; R 7 represents R 11 —O—CO—, R 12 —CO—CO—, R 13 —NH—CO—, R 14 —SO 2 —, R 15 —W—C(R 16 )(R 17 )—, R 19 —SO 2 NHCO—, R 20 —CONHCO—, R 21 —SO 2 NHSO 2 —, R 22 —CONHSO 2 —, or (M) 1/n OSO 2 —; R 11 , R 12 , R 13 , R 14 , R 19 , R 20 , R 21 , and R 22 each independently represent an alkyl group, an aryl group, or a heterocyclic group; R 15 represents a hydrogen atom or a block group; W represents an oxygen atom, a sulfur atom, or —N(R 18 )—; R 16 , R 17 and R 18 each independently represent a hydrogen atom or an alkyl group; and M represents a cation having a valency of n; wherein L represents a divalent linking group; Blst represents a ballast group which causes a coupler molecule to have diffusion resistance; T represents a substituent which leaves upon coupling reaction; and m represents an integer of from 0 to 3; wherein R 11 and R 11′ each independently represent an alkyl group having 1 to 20 carbon atoms; R 12 and R 12′ each independently represent a hydrogen atom or a group substituting for a hydrogen atom on a benzene ring; L represents an —S—group or a —CHR 13 —group; R 13 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms; and X 1 and X 1′ each independently represent a hydrogen atom or a group substituting for a hydrogen atom on a benzene ring.