| 摘要 |
PROBLEM TO BE SOLVED: To provide a reversible thermal coloring composition and a reversible thermal recording medium which hold stable properties of coloring and color extinction and which is excellent in thermal response and can meet high-speed extinction. SOLUTION: In regard to the reversible thermal coloring composition utilizing a coloring reaction between an electron-donating color developing compound and an electron accepting compound, a compound expressed by general formula 1 is contained as a color extinction accelerator in the composition. In formula 1, X denotes a bivalent group containing at least one or more C=O and R denotes a bivalent group constituted of a hydrocarbon and has at least one or more groups which branch from a hydrocarbon group constituting a cyclic structure containing X and are expressed by formula 2: -(R1 )m-Y-R2 , while n denotes 1 or 2, and R and X that are repeated when n is 2 may be identical or different. In formula 2, Y denotes a bivalent group constituted of a hetero atom, R1 a bivalent 1-11C aliphatic hydrocarbon group and R2 a 1-22C aliphatic hydrocarbon group, and m denotes 0 or 1. |
