To obtain an aliphatic polyester-based film hardly causing shear and wrinkle in printing and lamination ordinary applied to the film when being used as a wrapping film or a pressure-sensitive adhesive tape, and further having good torsion-fixing properties, and good hand-tearing properties for allowing the film to be easily torn off by the hand in every direction without limiting the direction.
This film is composed of an aliphatic polyester-based resin comprising an essential repeating unit of the formula O-CHR-CO (R is H or a 1-3C alkyl) and having 0.50-2.50 dl/g reduced viscosity (ηsp/c), and has the following characteristics (A) to (C): (A) the difference (Nx-Ny) of the refraction index (Nx) in the longitudinal direction and the refraction index (Ny) in the transverse direction is (-0.020)-0; (B) the dispersion of the (Nx-Ny) in the longitudinal direction is ≤0.005; and heat shrinkage at 120°C is ≤5%.
ODA NAONOBU
MORI KEIJI
OKUDAIRA TADASHI
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