Aqueous pigment liquid dispersion and ink-jet recording ink, and production method of aqueous pigment liquid dispersion

摘要

The present invention relates to an ink-jet recording ink which can simultaneously achieve long-term preservation stability, high luster, and light fastness of a printed image, and an aqueous pigment liquid dispersion to produce the ink. Moreover, the present invention relates to a production method of the aqueous pigment liquid dispersion. For the aforementioned objects, the applicant provides an aqueous pigment liquid dispersion, including: C. I. pigment green 36 (a); a styrene-acrylic acid type copolymer (b); a basic compound (c); and a wetting agent (d), wherein the styrene-acrylic acid type copolymer (b) has styrene-based monomer units of 60 mass % or more in the total of all the monomer units, an acid value of 120 to 240, and a weight average molecular weight of 6,000 to 40,000, and the mass ratio (b)/(a) is within a range from 0.15 to 0.25.

主权项

1. An aqueous pigment liquid dispersion, comprising:
C. I. pigment green 36 (a); a styrene-acrylic acid based copolymer (b); a basic compound (c); and a wetting agent (d), wherein the styrene-acrylic acid based copolymer (b) has an acid value of 120 to 240, a weight average molecular weight of 7,600-20,000, and styrene-based monomer units of 60 mass % or more in the total of all the monomer units constituting the styrene-acrylic acid based copolymer (b), and the mass ratio (b)/(a), which is the mass of the styrene-acrylic acid based copolymer (b) divided by the mass of the C. I. pigment green 36 (a), is within a range of 0.20-0.25; and an iron content within the C. I. pigment green 36 (a) is 30 ppm or less, a magnesium content within the C. I. pigment green 36 (a) is 50 ppm or less, and a silicon content is 45 ppm or less.