| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a diffusion film, having superior light beam transmittance and light diffusion by possessing inherent superior heat resistance and mechanical strength of a two-axis extension film, and to provide the light diffusion film obtained therefrom. SOLUTION: The method for manufacturing the light diffusion film having 50-99 pts.mass of a crystal polyester and a light diffusion layer obtained to biaxially extend a non-extension sheet consisting of a mixture containing 1-50 pts.mass of non-melting polymer particles performs biaxial extension in the vertical and the horizontal directions at an extension speed of less than 300%/sec at extension magnification of 2.5 times or higher. The light diffusion film manufactured by this method has entire light beam transmittance of 85% or higher, haze of 50% or higher, 3% or lower for the size change ratio at 150°C in the vertical and the horizontal directions and tensile strength of 100 MPa or higher in the vertical and the horizontal directions. COPYRIGHT: (C)2007,JPO&INPIT |
