English name (polyimide film; PI film), including homobenzene-type polyimide film and biphenyl polyimide film two categories. The former for the United States DuPont products, trade name Kapton, by the benzene tetracarboxylic anhydride and diaminodiphenyl ether system. The latter is produced by Japan UBE Corporation, trade name Upilex, biphenyl tetracarboxylic acid dianhydride and diphenyl ether diamine (R-type) or m-phenylenediamine (S-type) system.