| 摘要 |
<p>The present invention relates to a polyester film, including: a polyester resin which has diol components having at least 90 mol% of 1,4-cyclohexandimethanol, and dicarboxylic acid components having at least 80 mol% of terephthalic acid; and spherical monodispersed particles whose size is between 200 and 3,000 ppm for the polyester resin, wherein the glass temperature of the polyester resin is at least 88°C, and a heat shrinkable rate of the polyester film is not more than 3% in a vertical and a horizontal direction after maintaining the temperature at 150°C for 30 minutes. The polyester film is transparent, has outstanding heat resistance, and has excellent hydrolysis resistance while maintaining good film physical properties for a long time even if being exposed to the high temperature and humidity. In addition, the polyester film has no degradation of physical properties caused by crystallization at high temperature, thereby being suitable for an optical film for display, and having excellent winding properties due to a small friction coefficient of the spherical film.</p> |
