| 摘要 |
Provided are: a pigment dispersant that exhibits an effect when a small quantity thereof is added and that imparts a high degree of fine dispersibility, high stability, and high fluidity; a pigment dispersion liquid using the pigment dispersant; and technology that makes it possible to obtain a pigment dispersant in a manner that is environmentally friendly, that is easy to achieve, that is cost effective, and that achieves a superior degree of living radical polymerization. The pigment dispersant comprises, as a main component thereof, a polymer that: is formed by living radical polymerization in which two or more monomers including a methacrylate (A) having an acidic group or a basic group and a methacrylate macromonomer (B) that has a molecular weight of 500-5000 and a methacrylate residue on one end of a specific polymer chain thereof are used such that the ratio of the total mole number of methacrylate monomers among the raw material monomers is 20-50 moles to 1 mole of a polymerization initiator compound; is a graft copolymer comprising a main chain in which the (A) component-derived acidic groups or basic groups are bonded and a polymer chain that is derived from the (B) component; and comprises, by mass ratio, a proportion of 50-90 mass% of the polymer chain within the polymer. |
