White film and backlight using same
AssigneeToray Industries, Inc.
InventorsTomoko Kanaya, Tadami Matsuyama, Yoshihiko Sakaguchi, Osamu Watanabe
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Abstract
A white film including polymer film wherein both the thermal shrinkage rate in the longitudinal direction and that in the transverse direction of the film are not less than −0.2% and not more than 0.5% at 90° C., and a backlight for liquid crystal displays using such a white film. Since the white film hardly suffers from undulation or rise in its end portions, it is most suitable as a reflection film for backlights of liquid crystal displays. Since a backlight for liquid crystal displays using this white film can be used for a long time, it is applicable to liquid crystal displays of various electrical/electronic devices.
Claims14
A white film comprising polymer film having a thickness of 188 to 250 μm, containing air bubbles and having a thermal shrinkage rate in longitudinal directions of the film that are not less than 0.08% and not more than 0.15% at 90° C., in transverse directions of the film that are not less than −0.05% and not more than 0.01% at 90° C., wherein the white film has reflectance properties.
A white film comprising polymer film having a thickness of 188 to 250 μm, containing air bubbles and having a thermal shrinkage rate in longitudinal directions of the film that are not less than 0.08% and not more than 0.15% at 90° C., in transverse directions of the film that are not less than −0.05% and not more than 0.01% at 90° C., wherein mean reflectance of the white film in a wavelength range of 400 nm to 700 nm is not less than 85%.
Dependencies are inferred from the claim text.