| 摘要 |
PURPOSE:To obtain a matte film low in unevenness of matting and excellent in surface gloss by specifying the surface gloss, crystallite size and breaking strength of a biaxially oriented polyester film containing particles having a specified particle diameter and a specified content. CONSTITUTION:A biaxially oriented polyester film containing 0.1-5wt.% particles of a mean particle diameter of 0.5-10mum, which is a matte polyester film simultaneously satisfying the relationships of formulas I-IV. When the mean particle diameter of the particles is below 0.5mum, no film having a desired surface gloss can be obtained undesirably. When this diameter is above 10mum, the irregularity on the surface of the film is excessively large. When the content of the particles is below 0.1wt.%, no matting effect is available. When this content is above 5wt.%, the surface of the film is roughened, which is not desirable for practical use. |
