MULTILAYER FILM AND BIAXIALLY ORIENTED POLYESTER FILM

摘要

Disclosed is a multilayer film comprising 50 or more layers each of which is composed of a thermoplastic resin and has a thickness of less than 30 nm. Also disclosed is a biaxially oriented film which has a density of 1-1.4 g/cm<3>, a thermal shrinkage rate of -2 to 2% in the longitudinal direction at 180˚C, and an elongation at break of 100-1,000% at least in one direction. These films have solved conventional problems, and thus are highly rigid and excellent in dimensional stability at high temperatures, formability over wide temperature range, and transparency after heating.