POLYIMIDE RESIN VANISH, AND INSULATED ELECTRIC WIRE, ELECTRIC COIL AND MOTOR USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a polyimide resin vanish excellent in heat resistance and crazing resistance, and capable of forming an insulating layer having a low permittivity; and to provide an insulated electric wire excellent in heat resistance and crazing resistance, and capable of raising the corona discharge initiation.SOLUTION: A polyimide resin vanish has, as a main component, a polyimide precursor resin obtained by reacting an aromatic diamine with an aromatic tetracarboxylic anhydride, wherein the imide group concentration after the imidization of the polyimide precursor resin is >35.0% and <36.0%.