METHOD FOR PRODUCING KNEADED MATERIAL FOR AQUEOUS PIGMENT DISPERSION, AQUEOUS PIGMENT DISPERSION AND INK COMPOSITION USING THE KNEADED MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a technique for obtaining an excellent aqueous pigment dispersion and an ink composition which have a stably dispersed pigment (excellent dispersion stability) and maintain the dispersion in long-term preservation (excellent long-term storage stability).

SOLUTION: In the method for producing the kneaded material for the aqueous pigment dispersion by kneading a mixture comprising at least a resin, a water-soluble organic solvent and the pigment, a solid content ration in the mixture is ≥50 mass % and the kneading is carried out substantially not to change the mass of the mixture to produce the kneaded material for the aqueous pigment dispersion. The kneaded material is used to produce the aqueous pigment dispersion and the ink composition.

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