US4745005A
Expired / Lapsed
US
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Magnetic recording medium and method for making the same
Assignee: Panasonic Holdings Corp
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Filing: 1985-05-01
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Granted: 1988-05-17
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Expires: 2005-05-01
Abstract
Abstract A vertical magnetization recording medium is formed on a high polymer film substrate by vacuum deposition of Co-Cr film or deposition of Co-Cr film with preceding deposition of permalloy film, both with Ti-vacuum deposited interface film on the substrate face, whereby vertical orientation of the C-axis of Co-Cr film with respect to the film surface is easily obtainable, thereby assuring good characteristic as vertical magnetization recording medium.
Inventors
- 👤 Ryuji Sugita
- 👤 Toshiaki Kunieda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:39
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/06; C23C14/14; C23C14/20; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/7368; G11B5/7369; G11B5/739; G11B5/73923; G11B5/84; G11B5/85; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
62 words
A method of making a magnetic recording medium comprising the steps of: (1) vacuum-depositing Ti on a surface of a high polymer sheet, to form a Ti-undercoating having a thickness no greater than 800 Angstroms, and (2) vacuum-depositing a magnetization material consisting essentially of Co-Cr in the form of a layer on the surface of said Ti-undercoating, to form a magnetization film.
Claim 2
Independent Claim
62 words
A method of making a magnetic recording medium comprising the steps of: (1) vacuum-depositing Ti on a surface of a high polymer sheet, to form a Ti-undercoating having a thickness no greater than 800 Angstroms, and (2) vacuum-depositing a magnetization material consisting essentially of Co-Cr in the form of a layer on the surface of said Ti-undercoating, to form a magnetization film.
Claim 3
Dependent Claim
41 words
The method for making a magnetic recording medium according to claim 1, which further comprises intermediate steps (1) and (2), and the additional step of: vacuum-depositing a permalloy to form a permalloy intermediate layer between said Ti-undercoating and said magnetization film.
Claim 4
Dependent Claim
24 words
The method for making a magnetic recording medium according to claim 1, in which said vacuum deposition steps are applied to a moving surface.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-17 | 1991-11-16 | 1992-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-17 | 1995-11-16 | 1996-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-17 | 1999-11-16 | 2000-05-17 | $7700.00 | Window Closed / Lapsed |