POLYESTER DISPERSANT, PROCESS FOR PRODUCTION OF THE SAME, AND PIGMENT COMPOSITION USING THE SAME

摘要

Disclosed is a polyester dispersant which is produced by reacting a hydroxyl group in a vinyl polymer (a) having two hydroxyl groups in one terminal region thereof and optionally a hydroxyl group in a polyol compound (c) other than the vinyl polymer (a) with an acid anhydride group in an anhydrous tetracarboxylic acid (b) and optionally an acid anhydride group in an anhydrous tricarboxylic acid (d), wherein the vinyl polymer (a) is produced by the radical polymerization of an ethylenically unsaturated monomer in the presence of a compound (a1) having two hydroxyl groups and one thiol group in the molecule. Also disclosed is a process for producing the polyester dispersant. The polyester dispersant shows excellent dispersion property, fluidability and storage stability even when used in a small amount. The polyester dispersant is suitable for an offset ink, a gravure ink, a resist ink for a color filter, an inkjet ink, a coating, a colored resin composition and the like.