| 摘要 |
PROBLEM TO BE SOLVED: To provide a polymeric film which can be used as an insulator in an electric motor or a power generator and in a magnetic medium or in a packaging material. SOLUTION: The polymeric film comprises a first layer comprising (a) a mixture comprising 50-99.9 mass% polyethylene terephthalate (PET) and 0.1-50 mass% polyethylene naphthalate (PEN) or (b) a copolymer comprising 50-99.9 mass% ethylene terephthalate units and 0.1-50 mass% ethylene naphthalate units, based on the total weight of the first layer, the polymeric film further comprises a second layer comprising PEN and a third layer comprising PEN, and further comprises a first intermediate layer and a second intermediate layer, wherein each of the intermediate layers comprises (a) a mixture comprising 50-99.9 mass% polyethylene terephthalate (PET) and 0.1-50 mass% polyethylene naphthalate (PEN) or (b) a copolymer comprising 50-99.9 mass% ethylene terephthalate units and 0.1-50 mass% ethylene naphthalate units, based on the total weight of the layer, and wherein the first intermediate layer is interposed between the first and second layers, and the second intermediate layer is interposed between the first and third layers. The invention further provides a method of producing such a polymeric film. COPYRIGHT: (C)2011,JPO&INPIT |
