METHOD FOR PRODUCING AQUEOUS METHYL VIOLET LAKE PIGMENT DISPERSION COMPOSITION

PROBLEM TO BE SOLVED: To provide a method for producing an aqueous methyl violet lake pigment dispersion composition in higher efficiency, through finding a resin capable of making a flushing treatment of a methyl violet lake pigment as a hard-to-disperse pigment. SOLUTION: The method for producing the aqueous methyl violet lake pigment dispersion composition comprises the following process: A mixture comprising press cake of a methyl violet lake pigment 10-85 mass% in water content, an alkali-soluble resin composed of monomer units of 50-60 mass% of monopropoxyethyl maleate, 15-20 mass% of methyl methacrylate and 25-30 mass% of styrene, and 2-3.5 equivalents, based on the resin's neutralizing amount, of a basic compound is subjected to flushing treatment followed by removing separated water and then adding water and a basic compound in an amount necessary for dissolving the alkali-soluble resin in water to the system to disperse the methyl violet lake pigment in an aqueous medium. COPYRIGHT: (C)2007,JPO&INPIT