| 摘要 |
PURPOSE:To attain to enhance strength, Young modulus flatness, heat resistance and dimensional stability, by biaxially orienting an unoriented film or sheet, which is formed by applying melt extrusion molding to specific polyether ketone, under a specific condition. CONSTITUTION:Polyether ketone, which has a repeating unit represented by formula and of which the inherent viscosity is 0.4dl/g or more, is formed into an unoriented film or sheet by melt extrusion molding. Subsequently, this film or sheet is biaxially oriented at least 1.5 times in both longitudinal and lateral directions simultaneously or in an arbitrary order at a temp. from the secondary transition temp. thereof to 210 deg.C. By this method, a low cost general-purpose film excellent in strength, heat resistance and dimensional stability can be prepared and can be adapted to various uses such as an electric insulating material, a food packing material, a copy film and a tracing material. |
