US4753852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium comprising a magnetic Co-Ni-Cr alloy thin layer
Assignee: Victor Company of Japan Ltd
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Filing: 1986-03-21
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Granted: 1988-06-28
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Expires: 2006-03-21
Abstract
Abstract A magnetic recording medium for high density recording comprising a non-magnetic substrate, a Cr undercoat and a magnetic Ni-Cr-Co alloy thin layer formed on the substrate. The magnetic alloy thin layer has a thickness of from 400 to 1200 angstrom and a Cr content of from 3 to 17 atomic percent. As a result, improved magnetic characteristics and corrosion resistance of the medium are ensured.
Inventors
- 👤 Makoto Mizukami
- 👤 Toshio Kato
- 👤 Toshikazu Nishihara
- 👤 Toshiro Abe
- 👤 Akihiro Kimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:44
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/06; C23C14/14; C23C14/16; C23C14/165; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/7368; G11B5/7373; G11B5/739; G11B5/73911; G11B5/73913; G11B5/73917; G11B5/73919; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/12597; Y10T428/12625; Y10T428/12736; Y10T428/12743; Y10T428/1275; Y10T428/12771; Y10T428/12861
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
69 words
A magnetic recording medium which comprises a non-magnetic support, a Cr undercoat having a thickness of from 1000 angstrom to 1 micrometer formed on said support, and a magnetic thin layer of a Co-Ni-Cr alloy formed on said Cr undercoat in a thickness of from 400 to 2000 angstrom, said alloy having from 3 to 17 atomic percent of Cr and not more than 30 atomic percent of Ni.
Claim 2
Dependent Claim
69 words
A magnetic recording medium which comprises a non-magnetic support, a Cr undercoat having a thickness of from 1000 angstrom to 1 micrometer formed on said support, and a magnetic thin layer of a Co-Ni-Cr alloy formed on said Cr undercoat in a thickness of from 400 to 2000 angstrom, said alloy having from 3 to 17 atomic percent of Cr and not more than 30 atomic percent of Ni.
Claim 3
Dependent Claim
23 words
A magnetic recording medium according to claim 1, wherein said undercoat has a thickness in the range of from 2000 to 5000 angstrom.
Claim 4
Dependent Claim
22 words
A magnetic recording medium according to claim 1, wherein said alloy has a Cr content of from 7 to 13 atomic percent.
Claim 5
Dependent Claim
27 words
A magnetic recording medium according to claim 1, wherein the content of Cr in said alloy is in the range of from 5 to 15 atomic percent.
Claim 6
Dependent Claim
27 words
A magnetic recording medium according to claim 1, wherein said non-magnetic support is made of an aluminum disk plated with Ni-P on the surfaces of the disk.
References Cited (Backward Citations)
US4277540A
Cited
US4074016A
Cited
US4079169A
Cited
US4236946A
Cited
US4245008A
Cited
JPS57109127A
Cited
US4426265A
Cited
US4594296A
Cited
US4548871A
Cited
US4582746A
Cited
US4599280A
Cited
US4552820A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-06-28 | 1991-12-28 | 1992-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-28 | 1995-12-28 | 1996-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-28 | 1999-12-28 | 2000-06-28 | $7700.00 | Window Closed / Lapsed |