| 摘要 |
A method for producing a pigment dispersion composition can easily produce a pigment dispersion composition that exhibits excellent image density, dispersibility, and storage stability, has high resolubility, and forms an ink film that exhibits excellent marker resistance and scratch resistance. The method includes bringing a pigment (I) having a surface acidic group and a basic compound (II) having two or more amino groups selected from a primary amino group and a secondary amino group in its molecule, into contact with each other in an aqueous medium to prepare a pigment having an unreacted surface amino group, bringing the pigment into contact with a polyisocyanate polyurethane resin (III) having two or more isocyanate end groups so that the pigment and the polyisocyanate polyurethane resin are bonded via a urea bond to prepare a dispersion of a polyurethane resin-bonded pigment (A), and heating the dispersion of the polyurethane resin-bonded pigment (A) at 40 to 100°C for 1 to 30 days. |
