Patent ID: 7329632

Claim:
A thermal transfer ink, comprising: (1) an arylidene pyrazolone dye represented by the following formula (I): wherein ring A is a benzene ring which optionally has an substituent, each of R 1 and R 2 which are independent of each other, is a hydrogen atom, an alkyl group which optionally is substituted, an allyl group, an aryl group which optionally is substituted, or a cycloalkyl group which optionally is substituted, R 3 is a hydrogen atom, an alkyl group which optionally is substituted, an NR 9 R 10 group, an alkoxy group which optionally is substituted, an alkoxycarbonyl group which optionally is substituted, an aryl group which optionally is substituted, or a C(O)NR 9A R 10A group, R 4 is an alkyl group which optionally is substituted, or an aryl group which optionally is substituted, and each of R 9 , R 10 , R 9A and R 10A which are independent of one another, is a hydrogen atom, an alkyl group which optionally is substituted, or an aryl group which optionally is substituted; (2) a bispyrazolone methine dye represented by the following formula (II): wherein each of R 5 and R 6 which are independent of each other, is an alkyl group which optionally is substituted, an alkenyl group which optionally is substituted, or an aryl group which optionally is substituted, each of R 7 and R 8 which are independent of each other, is an alkyl group which optionally is substituted, an NR 9B R 10B group, an alkoxy group which optionally is substituted, an alkoxycarbonyl group which may be substituted, an aryl group which optionally is substituted, or a C(O)NR 9C R 10C group, and each of R 9B , R 10B , R 9C and R 10C which are independent of one another, is a hydrogen atom, an alkyl group which optionally is substituted, or an aryl group which optionally is substituted; and (3) a medium.