| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface light-diffusing polyester film having excellent heat resistance, mechanical strength, thickness accuracy and the like, achieving both total light transmittance and light diffusivity, suppressing curling due to heat originating from a bimetal structure, suppressing the occurrence of moire or scintillation when used for a liquid crystal display, and showing excellent post-processing property. <P>SOLUTION: The surface light-diffusing polyester film has a Δn<SB>ab</SB>(relating to the refractive index) of 0.015 to 0.060 and is characterized in that: (1) the film has a light-diffusing layer comprising a blended composition of 50 to 99 parts by mass of a crystalline polyester and 1 to 50 parts by mass of an additive incompatible with the polyester; (2) the film has a plane orientation coefficient ΔP of 0.08 to 0.16; (3) the film has a surface haze of ≥15%; (4) the film has an internal haze less than the surface haze; (5) the film has a tensile strength of ≥100 MPa; (6) the film has an S(3) factor, which represents diffusivity, of ≥30% and <50%; and moreover, the film shows heat shrinkage percentages HS150 close to both ends in the width direction of the film ranging from 0.7% to 2.0%, the difference in the HS150 close to both ends being ≤0.1%, and the amount of variation along the longitudinal direction in the HS150 close to both ends being ≤0.25%. <P>COPYRIGHT: (C)2009,JPO&INPIT |
