Magnetic recording media and process of producing them
Abstract
Abstract A magnetic recording medium and a process for producing it is disclosed. The medium is comprised of a non-magnetic flexible support base and a magnetic layer formed on a surface of the support base. The magnetic layer is preferably in the form of a thin, ferromagnetic metal film formed by vapor deposition. An overcoat layer of a fluorine-containing organic material is formed directly on the magnetic layer. The fluorine content of the overcoat layer continuously and gradually decreases in the direction toward the magnetic layer. Accordingly, high fluorine content near the surface of the overcoat layer provides improved smoothness near the surface whereas the lower fluorine content near the interface of the overcoat with the magnetic layer allows for strong adhesion between the overcoat and the underlying magnetic layer substrate. The media is formed by providing the flexible support base, forming the magnetic layer on the surface of the support base and forming the overcoat layer on the magnetic layer by performing plasma polymerizations of a fluorine-free monomer gas and a fluorine-containing monomer gas with a time lag. The overcoat layer is formed such that the fluorine content continually increases in a direction away from the magnetic layer.
Inventors
- 👤 Yoshihiro Arai
- 👤 Akira Nahara
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-05 | 1987-06-06 | 1987-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-05 | 1991-06-06 | 1991-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-05 | 1995-06-06 | 1995-12-06 | $7700.00 | Window Closed / Lapsed |