Patent ID: 6866706

Claim:
A thermal transfer ink, comprising: at least one dye (a); at least one dye selected from the group consisting of dye (b), dye (c) and a mixture thereof; and a medium; wherein (a) is a dye having a pyrazolone methine skeleton and represented by formula (I): wherein ring A represents an optionally substituted benzene ring, R 1 and R 2 each independently represent a hydrogen atom, an optionally substituted alkyl group, allyl group, an optionally substituted aryl group, or an optionally substituted cycloalkyl group, R 3 represents a hydrogen atom, an optionally substituted alkyl group, an NR 9 R 10 group, an optionally substituted alkoxy group, an optionally substituted alkoxycarbonyl group, an optionally substituted aryl group, or a C(O)NR 9A R 10A group, R 4 represents an optionally substituted alkyl group or an optionally substituted aryl group, and R 9 , R 10 , R 9A , and R 10A each independently represent a hydrogen atom, an optionally substituted alkyl group, or an optionally substituted aryl group, (b) is a dye having a quinophthalone skeleton and represented by formula (II): wherein rings B and C each independently represent an optionally substituted benzene ring, and X represents a hydrogen atom or a halogen atom, and (c) is a dye having an aminopyrazole azo skeleton and represented by formula (III): wherein ring D represents an optionally substituted benzene ring, R 5 represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted alkoxy group, an optionally substituted aryl group, an optionally substituted alkoxycarbonyl group, a C(O)NR 9B R 10B group, or an SO 2 R 9C group, R 6 represents a hydrogen atom, an optionally substituted alkyl group, or an optionally substituted aryl group, R 7 and R 8 each independently represent a hydrogen atom or an optionally substituted alkyl group, and R 9B , R 10B , and R 9C each independently represent a hydrogen atom, an optionally substituted alkyl group, or an optionally substituted aryl group.