Patent ID: 7404632

Claim:
An ink-jet recording ink, comprising a pigment and a compound represented by the following General formula (I): R—X Y n H General formula (I) wherein in General formula (I), R represents a hydrophobic group, or a group derived from a hydrophobic polymer; X represents a bivalent linking group having a hetero bond; n is an integer from 10 to 3500; and structural units of repeated Y comprise at least one structural unit represented by A, C or D, and further comprise 0 to 40% by mole of structural units represented by B: wherein in structural units A through D, R 1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R 2 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R 3 represents a hydrogen atom or a methyl group; R 4 represents a hydrogen atom, —CH 3 , —CH 2 COOH or an ammonium salt thereof or alkali metal salt thereof, or —CN; Z 1 represents a hydrogen atom, —COOH or an ammonium salt thereof or alkali metal salt thereof, or —CONH 2 ; and Z 2 represents —COOH or an ammonium salt thereof or alkali metal salt thereof, —SO 3 H or an ammonium salt thereof or alkali metal salt thereof, —OSO 3 H or an ammonium salt thereof or alkali metal salt thereof, —CH 2 SO 3 H or an ammonium salt thereof or alkali metal salt thereof, —CONHC(CH 3 ) 2 CH 2 SO 3 H or an ammonium salt thereof or alkali metal salt thereof, or —CONHCH 2 CH 2 CH 2 N + (CH 3 ) 3 Cl − .