AQUEOUS PIGMENT DISPERSION, METHOD FOR PRODUCING THE SAME, AND RECORDING LIQUID CONTAINING THE SAME

摘要

Disclosed is a recording liquid including an aqueous pigment dispersion, which has high dispersion stability and high discharge properties and gives a print with superior gloss. Specifically, the aqueous pigment dispersion contains a pigment; a polymer containing cationic monomer structural units and hydrophobic monomer structural units (hydrophobic-group-containing cationic polymer); and a polymer containing anionic monomer structural units and hydrophobic monomer structural units (hydrophobic-group-containing anionic polymer), in which the ratio of the number of anionic groups in the hydrophobic-group-containing anionic polymer to the number of cationic groups in the hydrophobic-group-containing cationic polymer is 1.0 or more and 8 or less. The molar ratio of the hydrophobic monomer structural units to the anionic monomer structural units in the hydrophobic-group-containing anionic polymer is from 5/95 to 50/50 or the content of the pigment is 51 percent by weight or more based on the solids content. This aqueous pigment dispersion is produced by dispersing a pigment with a hydrophobic-group-containing cationic polymer, subsequently subjecting the dispersion to ultrafiltration/microfiltration, and adding a hydrophobic-group-containing anionic polymer thereto.