| 摘要 |
<p>A multilayered polyester film which comprises layers A made of a polyester A and, alternately superposed therewith, layers B made of a polyester B and in which the outermost layers on the respective sides are layers A, characterized in that the polyester A has a melting point higher by at least 15°C than the melting point of the polyester B, the layers A have an oriented structure and the layers B have a substantially unoriented structure, the ratio of the total thickness of the layers A to that of the layers B, (a/b), is from 0.01 to 3, the film has a maximum in-plane breaking strength of 50 MPa or lower, and the difference between the maximum and minimum values of the strength is 20 MPa or smaller. The film is excellent in the isotropy of in-plane breaking strength and in transparency, has reduced unevenness in thickness, and has excellent processability.</p> |
