Patent ID: 6933348
Filing Date: 2005-08-23
Classification: C09D

Abstract:
1. A method of producing a powdery coating material by using: a curable acrylic resin (A) having a number average molecular weight of from 2,000 to 20,000 and a glass transition temperature of from 30 to 90° C. obtained by polymerizing a starting monomer containing from 15 to 50 mol % of an unsaturated compound which contains at least a glycidyl group and/or a methylglycidyl groups, and from 20 to 50 mol % of methyl methacrylate in a polymerization solvent selected from the group consisting of toluene, xylene and an alcohol solvent having a boiling point under normal pressure of from 70 to 120° C. such that when the toluene or the xylene is used as the polymerization solvent, said solvent is vapor-removed prior to being kneaded with the curable acrylic resin (A), a curing agent (B) and the alcohol solvent (C); the curing agent (B) capable of being reacted with the glycidyl group or the methylglycidyl group constituting the curable acrylic resin (A); and the alcohol solvent (C) having a boiling point under normal pressure of from 70 to 120° C.; said method comprising a kneading step of continuously kneading the curable acrylic resin (A), the curing agent (B) and the alcohol solvent (C) so that at least the curing agent (B) is dissolved in the alcohol solvent (C) at a temperature of not higher than 130° C., and a vapor-removing step of continuously vapor-removing the alcohol solvent (C) under a reduced pressure at a temperature of not higher than 130° C. wherein the powdery coating material is obtained by pulverizing a mixture of the curing agent (B) and the curable acrylic resin (A) obtained by removing the alcohol solvent (C) therefrom.