Biaxially oriented polyester film for magnetic recording media
US5252388A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 1991 |
| Grant date | Oct 12, 1993 |
| Priority date | — |
| Expiry date | Dec 13, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A biaxially oriented polyester film for magnetic recording media, which comprises: PA1 (A) 0.05 to 1.0% by weight of .theta.-aluminum oxide or mixed (.alpha.+.gamma.) aluminum oxide having an average particle diameter in the range of from 0.02 to 0.3 .mu.m and a specific surface area in the range of from 50 to 120 m.sup.2 /g, and PA1 (B) 0.01 to 1.5% by weight of inert particles having an average particle diameter which is in the range of from 0.1 to 1.5 .mu.m and greater than the average particle diameter of the aluminum oxide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.