| 摘要 |
PROBLEM TO BE SOLVED: To improve color developing sensitivity and preservation stability of an image by incorporating a diphenylsulfone derivative represented by the formula I in an electron acceptive compound and incorporating an ether compound represented by the formula II as an additive. SOLUTION: As an electron acceptive compound for color developing a dye precursor in reaction when heated, a diphenylsulfone derivative represented by the formula I (wherein R1, R2 are each an alkyl group, an alkenyl group, a phenylsulfonyl group or a halogen atom, m is an integer of 1 to 3, n is an integer of 0 to 2, and x, y are each an integer of 0 to 2) is used. As a sensitizer for constituting a heat sensitive recording layer, an ether compound represented by the formula II (wherein R3, R4 are each an alkenyl group, an alkyl group or an alkylcarbonyl group) is used. Thus, color developing sensitivity can be upgraded, and balance of preservation characteristics of an image can be improved. |
