| 摘要 |
PURPOSE:To obtain the subject film suitable for magnetic recording base film, etc., having excellent planing resistance, slipperiness and scratch resistance, comprising polyester containing specific amount of plasma-treated fine particle in atmosphere of specific oxygen concentration. CONSTITUTION:Fine particle-containing polyester obtained by adding and mixing 0.005-3wt.% (preferably 0.05-0.5wt.%) fine particle (preferably silicon dioxide having 0.1-2mum average diameter, etc.) plasma-treated in an atmosphere of >=50%, preferably >=90% oxygen concentration, preferably in the initial stage of polycondensation reaction of polyester formation, is molten, extruded in sheet-like, cooled and solidified, drawn in biaxial directions (preferably drawn 3.5-5.5 times in 1st stage and 2.8-3.7 times in 2nd stage), heat-treated (preferably treated at 170-240 deg.C for 1-200s) and performed controlling treatment of heat-shrinkage in transverse direction to afford biaxially oriented polyester film. |
