| 摘要 |
<p>The object of this invention is to provide a biaxially oriented polyester film suitable as a base film for high density magnetic recording media, small in track deviation and excellent in traveling durability and preservability, and to provide a production method thereof. The object of this invention can be achieved by a biaxially oriented polyester film, characterized in that the dimensional change rate (A) in the transverse direction of the film is in a range of -0.3 to 0% when the film is allowed to stand at 49 DEG C and 90% RH for 72 hours, while being loaded with 32 MPa in the machine direction.</p> |
