Process for preparing high-purity 5,5-2,2,2-trifluoro-1-(trifluoromethyl)-ethylidene bis-1,3-isobenzofuran dione

摘要

A process for the preparation of high-purity perfluorinated compounds, specifically of an aromatic tetracarboxylic acid and its anhydride, 5,5'-[2,2,2-trifluoro-1-(trifluoromethyl)-ethylidene]bis-1,3-isobenzof urandione, by a multi-step treatment of the crude compounds. The metal ion content of the compounds treated is reduced considerably. After polymerization with an aromatic diamine, the anhydride is used in microelectronics.