| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polyester film which prevents decline in a processing speed and yield in front/back coating processing of an optical sheet, eliminates the necessity of color tone adjustment work and can maintain high luminance to achieve high quality images. <P>SOLUTION: This optical biaxially-stretched polyester film roll is obtained by winding the biaxially-stretched polyester film which comprises at least three layers, includes 50% or more of polyester subjected to solid layer polymerization in an outermost layer and has 100-350 μm thickness around a core. In a film roll width direction excluding 10 mm at both ends, a difference (R) between a maximum value and a minimum value obtained by measuring a roll outer diameter corresponding to the film outermost layer at 1 mm intervals is 0.4 mm or less. Haze of the film is 2.5% or less. A color tone reflection method y value when the plurality of films are laminated so that total measured thickness is 900-1,100 μm and comes closest to 1,000 μm is 0.3230 or less. <P>COPYRIGHT: (C)2013,JPO&INPIT |
