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US4681813A
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Ceramic substrate for a thin layer magnetic head
Assignee: Proterial Ltd
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Filing: 1984-09-20
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Granted: 1987-07-21
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Expires: 2004-09-20
Abstract
Abstract A thin layer magnetic head comprising a ceramic substrate consisting essentially of 100 parts by weight of a ceramic material and 0.05 to 5 parts by weight of at least one compound from the group consisting of silicon oxide and iron oxide.
Inventors
- 👤 Hirohide Yamada
- 👤 Masahiko Sakakibara
- 👤 Yoshiharu Koike
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:33
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/60; G11B5/6005; C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/117; C04B35/48; C04B35/486; C04B35/488; G11B5/127; G11B5/187; G11B5/31; G11B5/3103; G11B5/3106; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/11; Y10T428/1157
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
64 words
A thin layer magnetic head having a sintered ceramic substrate, said substrate consisting essentially of 100 weight parts of a ceramic material and 0.05 to 5 weight parts of at least one compound from the group consisting of silicon oxide and iron oxide, the ceramic material consisting essentially of 20 to 55 weight % of titanium carbide and the balance being substantially aluminum oxide.
Claim 2
Dependent Claim
64 words
A thin layer magnetic head having a sintered ceramic substrate, said substrate consisting essentially of 100 weight parts of a ceramic material and 0.05 to 5 weight parts of at least one compound from the group consisting of silicon oxide and iron oxide, the ceramic material consisting essentially of 20 to 55 weight % of titanium carbide and the balance being substantially aluminum oxide.
Claim 3
Dependent Claim
67 words
The thin layer magnetic head as set forth in claim 1, wherein 5 to 60 mol % of the titanium carbide in said ceramic material is substituted by a carbide, a nitride or mixtures thereof, the carbide being at least one carbide of zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten, the nitride being at least one nitride of titanium, zirconium, hafnium, vanadium, niobium and tantalum.
Claim 4
Dependent Claim
37 words
The thin layer magnetic head as set forth in claim 1 wherein said substrate further includes 0.05 to 5 weight parts of a member selected from the group consisting of chromium oxide, tungsten oxide and mixtures thereof.
Claim 5
Dependent Claim
37 words
The thin layer magnetic head as set forth in claim 2 wherein said substrate further includes 0.05 to 5 weight parts of a member selected from the group consisting of chromium oxide, tungsten oxide and mixtures thereof.
Claim 6
Dependent Claim
27 words
The thin layer magnetic head as set forth in claim 1, 2, 3 or 4, wherein 5-60 mol% of the aluminum oxide is substituted by zirconium oxide.
Claim 7
Dependent Claim
45 words
The thin layer magnetic head as set forth in claim 5, wherein the zirconium oxide contains 2 to 10 mol% of at least one member selected from the group consisting of magnesium oxide, calcium oxide and yttrium oxide in solid solution within said zirconium oxide.
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) | 1990-07-20 | 1991-01-19 | 1991-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-20 | 1995-01-19 | 1995-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-20 | 1999-01-19 | 1999-07-21 | $7700.00 | Window Closed / Lapsed |