INK, INK CARTRIDGE, INK JET RECORDING METHOD AND INK JET RECORDING APPARATUS

摘要

An ink jet ink including a self-dispersible pigment, a salt, a polyoxyethylene alkyl ether and a water-soluble organic solvent. The self-dispersible pigment is a pigment to a surface of a particle of which a functional group containing at least a phosphonic acid group is bonded, the introduced amount of the functional group bonded to the self-dispersible pigment is 0.10 to 0.33 mmol/g. The salt is constituted by combining a specific cation with a specific anion. The value (Concentration of anion)×(Valence number of anion) of the salt in the ink is 0.005 to 0.06 mol/L. The water-soluble organic solvent includes glycerol, the content of which in the ink is 35% to 78% by mass based on the total content of the water-soluble organic solvent in the ink.