Abstract: A polyurethane resin-bonded pigment may exhibit excellent image density, dispersibility, storage stability, and resolubility, and may form an ink film that exhibits marker resistance and rubfastness. The polyurethane resin-bonded pigment is produced by bringing (I) a pigment having a surface acidic group into 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 to obtain a pigment having an unreacted surface amino group, and bringing the pigment having an unreacted surface amino group into contact with (III) a water-dispersible polyurethane resin having an isocyanate end group and (IV) a polyisocyanate compound to bond the pigment having an unreacted surface amino group and the water-dispersible polyurethane resin (III) having an isocyanate end group via a urea bond.

Abstract: A pigment that exhibits excellent image density, dispersibility, storage stability, and resolubility, and forms an ink film that exhibits marker resistance and rubfastness is provided. A polyurethane resin-bonded pigment is produced by bringing (I) a pigment having a surface acidic group into contact with (II) a water-dispersible polyurethane resin having a tertiary amino group and an anionic polar group or a nonionic polar chain in an aqueous medium. The pigment (I) is preferably self-dispersible carbon black having a surface acidic group.

Abstract: A method for producing a pigment dispersion composition having excellent image density, dispersibility, and storage stability, has high resolubility, and forms an ink film having 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 ammo 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.

Abstract: A method for producing a pigment dispersion composition having excellent image density, dispersibility, and storage stability, has high resolubility, and forms an ink film having 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.

Abstract: A polyurethane resin-bonded pigment may exhibit excellent image density, dispersibility, storage stability, and resolubility, and may form an ink film that exhibits marker resistance and rubfastness. The polyurethane resin-bonded pigment is produced by bringing (I) a pigment having a surface acidic group into 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 to obtain a pigment having an unreacted surface amino group, and bringing the pigment having an unreacted surface amino group into contact with (III) a water-dispersible polyurethane resin having an isocyanate end group and (IV) a polyisocyanate compound to bond the pigment having an unreacted surface amino group and the water-dispersible polyurethane resin (III) having an isocyanate end group via a urea bond.

Abstract: A pigment that exhibits excellent image density, dispersibility, storage stability, and resolubility, and forms an ink film that exhibits marker resistance and rubfastness is provided. A polyurethane resin-bonded pigment is produced by bringing (I) a pigment having a surface acidic group into contact with (II) a water-dispersible polyurethane resin having a tertiary amino group and an anionic polar group or a nonionic polar chain in an aqueous medium. The pigment (I) is preferably self-dispersible carbon black having a surface acidic group.