| 摘要 |
PURPOSE:To obtain high-purity 4,4',5,5'-binaphthyltetracarboxylic acid dianhydride useful as a raw material for polyimide resin. CONSTITUTION:A 4-halogenonaphthalic acid or an alkali metallic salt thereof is dehalogenated and dimerized in the presence of (1) a palladium catalyst, (2) water and (3) a polyhydric alcohol and/or a formaldehyde, then the dimerized product is precipitated with an acid and the prepared crystal is made anhydrous to give 4,4',5,5'-binaphthyltetracarboxylic acid dianhydride. |
