| 摘要 |
PURPOSE:To obtain the title film suitable for magnetic tape, electrical insulation and condenser with an extremely small amount of low-molecular weight compound precipitated by copolymerizing a dicarboxylic acid component with a diol component having a specific molar volume. CONSTITUTION:(A) 1-20mol% diol component (e. g. 1,4-cyclohexanedimethanol) having >=70cm<3>/mol, preferably <=200cm<3>/mol molar volume of repeating structure unit and (B) a diol component such as ethylene glycol are polymerized with (C) a dicarboxylic acid component such as terephthalic acid to give pellets having >=0.75 intrinsic viscosity. The pellets are fed to a melt extruder, extruded into a sheet, and biaxially oriented to give the aimed film having >=0.70 intrinsic viscosity, 1.3600-1.3849g/cm<3> density and >=800kg/mm<2> sum of Young's moduli of longitudinal direction and width direction. |
