| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an aliphatic polyester-based biaxially oriented film hardly causing deterioration of planarity, shear and the like in printing or lamination, having excellent processing properties, excellent in hand-tearing properties and torsion properties, and useful as a wrapping film, a film for a pressure- sensitive adhesive tape or the like. SOLUTION: This film is composed of an aliphatic polyester comprising an essential repeating unit of the formula O-CHR-CO (R is H or a 1-3C alkyl) and having 0.05-2.50 dl/g reduced viscosity (ηsp/C) as an essential polymer component, and has (-0.020)-0 value (Nx-Ny) obtained by reducing the refraction index (Ny) in the transverse direction from the refraction index (Nx) in the longitudinal direction, <=0.005 width of the dispersion of the (Nx-Ny) in the transverse direction of the film, and <=5% heat shrinkage in the longitudinal direction at 120 deg.C.</p> |
