PREPARATION METHOD FOR AQUEOUS POLYURETHANE RESIN-PIGMENT DISPERSION, AQUEOUS POLYURETHANE RESIN-PIGMENT DISPERSION, AND INK COMPOSITION

摘要

A method of producing a polyurethane resin-bonded pigment aqueous dispersion includes causing (I) a pigment having a surface acidic group to come in contact with (II) a basic compound having two or more amino groups selected from a primary amino group and a secondary amino group in its molecule in an aqueous medium so that the pigment has an unreacted surface amino group, and causing the pigment to come in contact and react with (III) a polyurethane resin having an isocyanate end group. A polyurethane resin-bonded pigment aqueous dispersion produced by the method exhibits excellent image density, dispersibility, and storage stability.