Magnetic recording medium
US6468628B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2001 |
| Grant date | Oct 22, 2002 |
| Priority date | — |
| Expiry date | Jun 4, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31725
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a magnetic recording medium having a magnetic layer directly formed on at least one surface of a base film that comprises, as the essential ingredient, an aromatic polyamide, in which the number of protrusions having a height of at least 10 nm on the surface of the magnetic layer, Na(10) (/mm2), the number of protrusions having a height of at least 50 nm thereon, Na(50) (/mm2), and the number of protrusions having a height of at least 10 nm on the surface of the base film coated with the magnetic layer, Na(10)′ (/mm2), all satisfy the following formulae:2×104≦Na(10)≦2×107, 0≦Na(50)≦5×104, −0.9≦(Na(10)−Na(10)′)/Na(10)′≦0. The medium has, as the non-magnetic substrate (base film), a highly-tough, aromatic polyamide film, and the surface profile of its magnetic layer and that of its base film are specifically controlled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.