| 摘要 |
PURPOSE:To improve scratch resistance by specifying the distribution of the concn. of inert particles in a film consisting mainly of a thermoplastic resin and the inert particles. CONSTITUTION:A pelletized thermoplastic resin contg. a specified amt. of inert particles with a degree of vacuum of not more than 1.6 is extruded into a sheet and set by cooling to give an unstretched film, which is stretched in the longitudinal direction at a temp. within the range of from 10 deg.C lower to 10 deg.C higher than the glass transition paint of the resin at a stretching rate of 1,000-10,000%/min, and then stretched in the transverse direction at a relative humidity of 50% and a temp. within the range of from 10 deg.C lower to 30 deg.C higher than the glass transition paint at the stretching rate of 1,000-20,000%/min to give a biaxially oriented thermoplastic resin film wherein a depth (a distance from the surface), A nm, at a point where the particle concn. is one tenth of that at the surface and a depth, B nm, at a point (B>A) where the particle concn. is the same as that at the surface satisfy relations I and II in a distribution curve of the particle concn. measured from at least one surface of the film to a point of 3,000nm deep. |
