Patent ID: 7964660

Claim:
A process for producing a water-based pigment dispersion comprising: (1) mixing (A) an emulsion composition comprising a water-insoluble polymer having a weight-average molecular weight of from 90,000 to 400,000 and comprising a salt-forming group, an organic solvent having a solubility in 100 g of water of from 5 to 40% by weight as measured at 20° C., a neutralizing agent and water, with (B) a pigment, to obtain a preliminary dispersion having a content of non-volatile components of from 5 to 50% by weight of the preliminary dispersion and a weight ratio of the organic solvent to water (organic solvent/water) of from 0.1 to 0.9; (2) continuously dispersing the preliminary dispersion by using a media particle-containing dispersing device and continuously separating the resultant dispersion from media particles; and (3) further dispersing the resultant dispersion by using a homogenizer.