| 摘要 |
PROBLEM TO BE SOLVED: To provide a biaxially oriented polyester film for insert molding which shows outstanding molding properties and also a biaxially oriented polyester film for insert molding which shows outstanding molding properties and solvent resistance and is especially best suited for use in applications in which a resin molding is colored and/or a design is imparted. SOLUTION: This polyester film shows that a degree of in-plane orientationΔP, sought by the formula:ΔP=(Nx+Ny)/2-Nz is 0.09 or more and 0.15 or less, when the indices of refraction of the film in the longer, the width and the thickness direction are given as Nx, Ny, Nz respectively. In addition, the polyester film has the described degree of in-plane orientationΔP and the average index of refraction N(Nx+Ny+Nz)/3 of 1.59 or more of the film. |
