| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a base for magnetic recording medium with excellent dimensional stability and resistance against cracking. <P>SOLUTION: The base for magnetic recording medium, for which layers (M layers) including metal based oxide are made on both surfaces of a biaxially oriented polyester film while surface resistances of the M layers range from 1×10<SP>2</SP>to 1×10<SP>13</SP>Ω, has Poisson's ratio within 0.10 to 0.30 when being loaded 10 MPa in the longitudinal direction of the base, humidity expansion coefficient 1 to 8 ppm/%RH in the width direction of the base, and further the sum of Youngs modulus 10 to 22 GPa in the longitudinal direction and width direction, thereby realizing the high density magnetic recording medium with less dimension change due to environmental change and preservation, less cracking, low error rate, and excellent running durability. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
