BIAXIALLY ORIENTED COPOLYESTER/POLYOLEFIN BI- OR TRILAYER FILM AND METHOD FOR MAKING THE SAME

摘要

Disclosed herein is a bi- or trilayer film comprising one or two biaxially oriented copolyester film layers and a polyolefin layer bonded to one surface of said biaxially oriented copolyester film layer(s), wherein the copolyester is PENBB. The laminated film may also include a metal layer bonded to the copolyester surface opposite the surface bonded to the polyolefin. The metal layer preferably has a thickness of 0.03 to 0.3 mu m. The polyolefin preferably has a thickness from about 5 to about 30 mu m and a birefringence of 0 to about 0.02. PENBB as mentioned herein is a copolyester containing units of formula (I). Such films are useful in capacitor applications.