To provide water-based ink for inkjet recording excellent in hue and in fastness against light, heat and ozone and prevented from causing reduction in an optical density (OD value) in a high humidity environment.
The water-based ink for inkjet recording includes a colorant, water, and a water-soluble organic solvent. The colorant includes a dye represented by general formula (1). The water-based ink further includes a cationic polymer. In general formula (1): R1 is a hydrogen atom, a substituted/unsubstituted alkyl group, or a substituted/unsubstituted aryl group; R2 is a hydrogen atom, a halogen atom or a cyano group; R3 is a hydrogen atom, a substituted/unsubstituted alkyl group, a substituted/unsubstituted aryl group, or a substituted/unsubstituted heterocyclic group; R4, R5, R6 and R7 are each a hydrogen atom, a substituted/unsubstituted alkyl group, a substituted/unsubstituted aryl group, a substituted/unsubstituted heterocyclic group, a substituted/unsubstituted sulphonyl group, or a substituted/unsubstituted acyl group wherein R4, R5, R6 and R7 may be the same or different provided R4 and R5 are not hydrogen atoms at the same time and R6 and R7 are not hydrogen atoms at the same time; and A1 and A2 are both substituted/unsubstituted carbon atoms, or one of them is a substituted/unsubstituted carbon atom while the other is a nitrogen atom.
MAEDA MITSUNORI
Yumi Nakayama
Reiko Yoshida
Isaji So
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