BIAXIALLY ORIENTED LAMINATE POLYESTER FILM AND OPTICAL LAMINATE FILM

摘要

The present invention is a biaxially oriented laminate polyester film characterized by satisfying (1) through (5) below. (1) The laminate polyester film comprises at least three layers and has a polyester layer (A) (referred to hereinafter as the "A layer") and a polyester layer (B) (referred to hereinafter as the "B layer") on both sides of the A layer. (2) The oligomer content of a polyester resin composition constituting the A layer is 1.5 wt% or less with respect to the total amount of the polyester resin composition. (3) The intrinsic viscosity (IV) of the polyester resin constituting the A layer is 0.45 dl/g to 0.70 dl/g. (4) The oligomer content of the polyester resin composition constituting the B layer is 0. 5 wt% or less with respect to the total amount of the polyester resin composition constituting the B layer. (5) The intrinsic viscosity (IV) of the polyester resin constituting the B layer is 0.70 dl/g to 0.90 dl/g.