PROCESS FOR PRODUCING AQUEOUS PIGMENT DISPERSIONS FOR INK-JET RECORDING

摘要

A process is provided for producing aqueous pigment dispersions for ink jet recording in which fine pigments are stably dispersed and such a state can be maintained for a long period of storing. Moreover, a process is provided for producing aqueous pigment dispersions for ink jet recording in which the time required for production such as dispersing time is short, and the production efficiency is high. The process for producing aqueous pigment dispersions for ink jet recording includes a first step of kneading (1) a styrene-acrylic type resin with a styrene type monomer unit of 50 to 90 mass %, and at least one unit selected from an acrylic monomer unit and methacrylic monomer unit, having an acid value of 50 to 300, (2) a pigment, (3) a basic compound, and (4) a humectant to produce a solid colored kneaded product, and a second step of dispersing the solid colored kneaded product in an aqueous medium comprising water or water and humectant.