WATER-BASED BLACK INK COMPOSITION FOR INK JET RECORDING AND IMAGE FORMING METHOD

摘要

A water-based black ink composition for ink jet recording including: a carbon black pigment at least partially coated with a water-insoluble first dispersant polymer containing a structural unit represented by the following formula (1) and a structural unit different from the structural unit represented by the following formula (1); a coloring pigment selected from the group consisting of a phthalocyanine pigment, a quinacridone pigment and an azo pigment, the coloring pigment being at least partially coated with the first dispersant polymer or a second dispersant polymer consisting of the same structural units as the structural units constituting the first dispersant polymer but having a composition ratio of the structural units different from a composition ratio of the structural units of the first dispersant polymer; and an aqueous medium: