| 摘要 |
PROBLEM TO BE SOLVED: To improve image storage stability and heat resistance by using a specific diphenylsulfone crosslinking type compound as an organic developer and also using an aromatic compound having a specific diphenylsulfone skeleton. SOLUTION: A heat-sensitive color developing layer contains a diphenylsulfone crosslinking type compound represented by formula I (X and Y are each 1-12C saturated or unsaturated hydrocarbon group which may be different, may be linear or branched or may have an ether bond, R1 to R6 are each independently halogen atom, 1-6C alkyl group or alkenyl group, m, n, p, q, r and t are each an integer of 0 to 4, and a is an integer of 1 to 10) and 0.01 to 0.9 pt.wt. of a compound represented by formula II (R7 is unsubstituted or substituted 1-4C alkyl group, aralkyl group, phenyl group or a hydrogen atom) to 1 pt.wt. of the developer represented by the formula I. |
