US4517257A
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Recording media comprising vertical magnetization layers essentially consisting of quaternary Co--Ni--Zn--P alloys
Assignee: Victor Company of Japan Ltd
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Filing: 1983-09-13
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Granted: 1985-05-14
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Expires: 2003-09-13
Abstract
Abstract Magnetic recording media suitable for use in vertical magnetization recording systems are described. The media comprise a magnetic layer on at least one side of a substrate. The magnetic layer is made of a specific type of quaternary alloy. The alloy essentially consists of from 3 to 42 wt % of Co, from 54 to 89 wt % of Ni, from 4 to 8 wt % of P, and from 0.1 to 3.2 wt % of Zn provided that (7.2 X P +12.8) wt %≦X Ni ≦(7.2 X P +43.2) wt % in which X P represents a content of P and X Ni represents a content of Ni, both expressed by wt %.
Inventors
- 👤 Shigeo Shimizu
- 👤 Toshio Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:18
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/65; G11B5/657; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
122 words
A magnetic recording medium for vertical magnetization recording which comprises a substrate and a magnetic film of a Co--Ni--Zn--P alloy formed on at least one side of the substrate, said alloy consisting essentially of from 3 to 42 wt% of Co, from 54 to 89 wt% of Ni, from 4 to 8 wt% of P, and from 0.1 to 3.2 wt% of Zn provided that (7.2 X p +12.8) wt%≦X Ni ≦(7.2 X p +43.2) wt% in which X p represents a content of P and X Ni represents a content of Ni, both expressed by wt% whereby said magnetic film satisfies the following inequality: K⊥>2πMs 2 wherein K⊥ is an intrinsic vertical anisotropy constant, and 2πMs 2 is a saturation magnetization.
Claim 2
Dependent Claim
122 words
A magnetic recording medium for vertical magnetization recording which comprises a substrate and a magnetic film of a Co--Ni--Zn--P alloy formed on at least one side of the substrate, said alloy consisting essentially of from 3 to 42 wt% of Co, from 54 to 89 wt% of Ni, from 4 to 8 wt% of P, and from 0.1 to 3.2 wt% of Zn provided that (7.2 X p +12.8) wt%≦X Ni ≦(7.2 X p +43.2) wt% in which X p represents a content of P and X Ni represents a content of Ni, both expressed by wt% whereby said magnetic film satisfies the following inequality: K⊥>2πMs 2 wherein K⊥ is an intrinsic vertical anisotropy constant, and 2πMs 2 is a saturation magnetization.
Claim 3
Dependent Claim
18 words
The medium according to claim 1, wherein said magnetic layer is formed on one side of said substrate.
Claim 4
Dependent Claim
18 words
The medium according to claim 1, wherein said magnetic layer is formed on each side of said substrate.
Claim 5
Dependent Claim
49 words
The medium according to claim 1, wherein said alloy consists essentially of from 5 to 22 wt% of Co, from 73 to 85 wt% of Ni, from 4 to 8 wt% of P, and from 0.1 to 3.2 wt% of Zn provided that X Ni <7.2 X p +43.2.
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) | 1988-05-13 | 1988-11-12 | 1989-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-13 | 1992-11-12 | 1993-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-13 | 1996-11-12 | 1997-05-14 | $7700.00 | Window Closed / Lapsed |