Polyester film for magnetic recording media
US4670319A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 1986 |
| Grant date | Jun 2, 1987 |
| Priority date | — |
| Expiry date | May 29, 2006 |
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 use in thin metallic film-type magnetic recording media, said polyester film having a first surface to which a thin metallic film as a magnetic recording layer is to be applied and a second surface coated with an easily slippable layer composed of an organic polymeric binder and inert fine solid particles dispersed therein, the first surface having (a) large protrusions with a diameter of 0.2 to 2 micrometers and a height of 20 to 200 angstrom distributed at a density of at least 10.sup.3 but less than 10.sup.6 per mm.sup.2, and (b) small protrusions with a diameter of 0.01 to 0.1 micrometer and a height of 10 to 100 angstrom distributed at a density of from 10.sup.6 up to 10.sup.9.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.