Ink composition, ink set and image forming method

Abstract

The present invention provides an inkjet ink composition, which is excellent in dispersion stability, discharge reliability and suppression of lowering of liquid repellency of the inkjet head member, and which includes a pigment, a polymer compound, a water soluble organic solvent, a silicon compound and water, the polymer compound including a structural unit represented by Formula (1), a structural unit represented by Formula (2), and a structural unit represented by Formula (3); the water soluble organic solvent being a diol compound including a repetition structure formed from oxyalkylene groups having 2 or 3 carbon atoms; and the silicon compound being selected from the group consisting of colloidal silica and water-soluble alkali metal salts of silicic acid: wherein R1 to R3 each independently represents a hydrogen atom or a methyl group; R4 represents an alkyl group having 1 to 10 carbon atoms; and n is 1 to 20.

Dependencies are inferred from the claim text.