US4804590A
Expired / Lapsed
US
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Abrasion resistant magnetic recording member
Assignee: Ulvac Inc
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Filing: 1986-11-25
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Granted: 1989-02-14
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Expires: 2006-11-25
Abstract
Abstract An abrasion resistant magnetic recording member having a carbonaceous surfacial protective film for protecting a surface of a magnetic film formed on a substrate, and the carbonaceous surfacial protective film is formed of a lower layer comprising a comparatively hard carbonaceous film and an upper layer comprising a comparatively soft carbonaceous film.
Inventors
- 👤 Kyuzo Nakamura
- 👤 Yoshifumi Ota
- 👤 Taiki Yamada
- 👤 Michio Ishikawa
- 👤 Noriaki Tani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:21
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; G11B5/726; G11B5/7262; G11B5/7264; G11B5/7266; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
128 words
An abrasion resistant magnetic recording member comprising a carbonaceous surfacial protective film formed on a surface of a magnetic film formed on a surface of a nonmagnetic substrate, wherein the carbonaceous surfacial protective film has a lower layer of comparatively hard carbonaceous film and an upper layer of comparatively soft and lubricative carbonaceous film, said protective film either being formed through an intermediate layer on the surface of the magnetic film or being formed, by a method other than arc deposition, directly on the surface of the magnetic film, wherein the lower layer contains 5 at.% or less of hydrogen, fluorine, or a combination of hydrogen and fluorine, and wherein the upper layer contains 6 at.% or more of hydrogen, fluorine, or a combination of hydrogen and fluorine.
Claim 2
Dependent Claim
128 words
An abrasion resistant magnetic recording member comprising a carbonaceous surfacial protective film formed on a surface of a magnetic film formed on a surface of a nonmagnetic substrate, wherein the carbonaceous surfacial protective film has a lower layer of comparatively hard carbonaceous film and an upper layer of comparatively soft and lubricative carbonaceous film, said protective film either being formed through an intermediate layer on the surface of the magnetic film or being formed, by a method other than arc deposition, directly on the surface of the magnetic film, wherein the lower layer contains 5 at.% or less of hydrogen, fluorine, or a combination of hydrogen and fluorine, and wherein the upper layer contains 6 at.% or more of hydrogen, fluorine, or a combination of hydrogen and fluorine.
Claim 3
Dependent Claim
40 words
An abrasion resistant magnetic recording member claimed in claim 1, wherein the lower layer of comparatively hard carbonaceous film comprises a sputter carbon film, and the upper layer of comparatively soft and lubricative carbonaceous film comprises a PCVD carbonaceous film.
Claim 4
Dependent Claim
23 words
An abrasion resistant magnetic recording member claimed in claim 2, wherein the PCVD carbonaceous film contains 6 at.% or more of hydrogen atoms.
Claim 5
Dependent Claim
23 words
An abrasion resistant magnetic recording member claimed in claim 2, wherein the PCVD carbonaceous film contains 6 at.% or more of fluorine atoms.
Claim 6
Dependent Claim
29 words
An abrasion resistant magnetic recording member claimed in claim 2, wherein the PCVD carbonaceous film contains 6 at.% or more of a total of hydrogen atoms and fluorine atoms.
Claim 7
Dependent Claim
54 words
An abrasion resistant magnetic recording member claimed in claim 1, wherein the lower layer of comparatively hard carbonaceous film comprises a PCVD carbonaceous film containing 5 at.% or less of hydrogen atoms, and the upper layer of comparatively soft carbonaceous film comprises a PCVD carbonaceous film containing 6 at.% or more of hydrogen atoms.
Claim 8
Dependent Claim
54 words
An abrasion resistant magnetic recording member claimed in claim 1, wherein the lower layer of comparatively hard carbonaceous film comprises a PCVD carbonaceous film containing 5 at.% or less of fluorine atoms, and the upper layer of comparatively soft carbonaceous film comprises a PCVD carbonaceous film containing 6 at.% or more of fluorine atoms.
Claim 9
Dependent Claim
66 words
An abrasion resistant magnetic recording member claimed in claim 1, wherein the lower layer of comparatively hard carbonaceous film comprises a PCVD carbonaceous film containing 5 at.% or less of a total of hydrogen atoms and fluorine atoms, and the upper layer of comparatively soft carbonaceous film comprises a PCVD carbonaceous film containing 6 at.% or more of a total of hydrogen atoms and fluorine atoms.
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) | 1992-02-14 | 1992-08-15 | 1993-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-14 | 1996-08-15 | 1997-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-14 | 2000-08-15 | 2001-02-14 | $7700.00 | Window Closed / Lapsed |