| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multilayer oriented film having a reflective polarization function, in which the polarizing performance is further enhanced compared to a conventional film as well as shift in a hue of transmitted polarized light depending on an incident angle in an oblique direction is prevented for the light obliquely incident to the film. <P>SOLUTION: The multilayer oriented film comprises alternately laminated first layers and second layers in total 251 layers or more. The first layer is a layer having a thickness of 0.01 to 0.5 μm and comprising a polyester, which contains: (i) as a dicarboxylic acid component, a specified dicarboxylic acid component by 5 mol% or more and 70 mol% or less containing naphthoic acid component, and a dicarboxylic acid component having a phenylene group; and (ii) as a diol component, a diol component having a 2-4C alkylene group or a 6C alicyclic group. The second layer is a layer having a thickness of 0.01 to 0.5 μm and comprising an optically isotropic copolymer polyester having an average refractive index of 1.55 or more and 1.62 or less. The multilayer oriented film has a specified thickness ratio and a specified difference in the diffraction index between the first layer and the second layer, and shows an average reflectance of 90% or more for a P-polarized light component each at an incident angle of 0 degree and 50 degrees and an average reflectance of 15% or less for a S-polarized light component each at an incident angle of 0 degree and 50 degrees. <P>COPYRIGHT: (C)2013,JPO&INPIT |
