| 摘要 |
PROBLEM TO BE SOLVED: To improve the image preserving property, and the color developing sensitivity by a method wherein in a heat-sensitive color developer which is used for a material for heat-sensitive recording, an isocyanate compound, a colorless or pale colored electron donative dye precursor, and a hydroxyl group- containing heterocyclic compound are contained. SOLUTION: In a heat-sensitive color developer for a heat-sensitive recording material which is used for a heat-sensitive recording method, an isocyanate compound, a colorless or pale colored electron donative dye precursor, and a hydroxyl group-containing heterocyclic compound are contained. The isocyanate compound which is used in this case, is an isocyanate adduct compound of which the melting point is 40 deg.C or higher, and for such an isocyanate adduct compound, preferably, those which are represented by formulas I, II are used. In the formulas, (m) indicates an integer of 0-5, and (n) indicates an integer of 1-2. Also, hydrogen atom of a benzene ring may be replaced by an aromatic compound residue, or an aliphatic compound residue or a heterocyclic compound residue, X1 , X2 indicate -SO2 -, -O- or the like. |
