REFINING METHOD FOR HIGH-PURITY ETHYNYL GROUP-CONTAINING AROMATIC CARBOXYLIC ACID AND NEW CRYSTAL THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a high-purity ethynyl group-containing aromatic carboxylic acid, particularly a high-purity 5-(phenylethynyl)isophthalic acid as an intermediate useful for e.g. synthesizing high-performance polymers. SOLUTION: The subject refining method for e.g. 5-(phenylethynyl)isophthalic acid reduced in metal ion content comprises acidifying-out or refining 5-(phenylethynyl)isophthalic acid by subjecting the 5-(phenylethynyl)isophthalic acid to hot agitation treatment in an aqueous medium. COPYRIGHT: (C)2004,JPO