PROCESS FOR PRODUCING AQUEOUS PIGMENT DISPERSIONS FOR INK JET RECORDING

摘要

A process for producing a water based pigment dispersion for ink jet recordi ng wherein a pigment of minute particle diameter is stably dispersed, the dispersion maintained for long-term storage. Further, a process for producin g a water based pigment dispersion for ink jet recording, which can reduce production time, for example, dispersing time and thus ensures high producti on efficiency. In particular, a process for producing a water based pigment dispersion for ink jet recording, comprising the first step of milling together a styrene acrylic resin (1) of 50 to 300 acid value wherein at leas t one unit selected from among a styrene monomer unit, an acrylic acid monomer unit and a methacrylic acid monomer unit is contained in a proportion of 50 to 90 mass%, a pigment (2), a wetting agent (3) and a basic compound (4) to thereby obtain a solid colored milling product and the second step of dispersing the solid colored milling product in water or a water base medium consisting of water and a wetting agent.