Hydrophobic cationic dyes and thermal transfer ink ribbons using the same

摘要

Disclosed are diazahemicyanine hydrophobic cationic dyes represented by the formula (1): (1) wherein R1, R2, R3 and R4 are lower alkyl groups having not more than 5 carbon atoms, R5 is a lower alkyl group having not more than 5 carbon atoms or a lower alkoxy lower alkyl group having not more than 6 carbon atoms, and Z- is a counter ion having a hydrophobic organic group, and a thermal transfer ink ribbon having a substrate and and ink layer laminated thereon containing said cationic dye.