摘要 |
<p>The present invention provides a biaxially oriented polyester film made of a polyester containing 0.01 to 5% by weight of crosslinked polymer particles characterized by: (1) having a particle size distribution ratio ( gamma ) of 1.3 to 3.5, (2) having an average particle diameter of 0.1 to 2 mu m, (3) having a non-circularity of 3.4 or more, and (4) having a standard deviation of non-circularity, of at least 0.16. The polyester film of the present invention has a flat surface having a small number of large protuberances, excellent running property and excellent winding property, and can be produced economically. The film has excellent properties for use as a base for various magnetic recording media.</p> |