Biaxially oriented polyester film for magnetic recording media containing theta or mixed alpha plus gamma aluminum oxide and inert organic particles
US5368932A · kind A · utility
7Cited by
5References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1993 |
| Grant date | Nov 29, 1994 |
| Priority date | — |
| Expiry date | Jun 11, 2013 |
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 organic 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.