BIAXIALLY ORIENTED POLYESTER FILM APPLIED TO WINDOW

摘要

PROBLEM TO BE SOLVED: To provide a biaxially oriented polyester film used as a shading film applied to a window reduced in discoloration/fading during long-term use even if an ultraviolet absorber or a radical absorbent is not used. SOLUTION: The biaxially oriented polyester film applied to the window is a co-extrusion laminated film comprising at least three polyester layers and a dye substantially dissolved in a polyester is added to an intermediate layer and all of layers contain no ultraviolet absorber or radical absorbent. The hue changeΔE*ab of the film when the film is directly irradiated for 80 hr by an ultraviolet carbon arc lamp is not more than 2.0.