US4670353A
Expired / Lapsed
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Magnetooptical recording medium
Assignee: Canon Inc
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Filing: 1985-10-01
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Granted: 1987-06-02
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Expires: 2005-10-01
Abstract
Abstract A magnetooptical recording medium comprises a ternary amorphous magnetic alloy of Tb-Fe-Co.
Inventors
- 👤 Yoshifumi Sakurai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:35
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; G03; G03G; G03G5/00; G03G5/16; H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/12; H01F10/13; H01F10/133; H01F10/135; H01F10/137; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12431
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
73 words
A magnetoopical recording medium comprising a recording layer of an amorphos alloy having an axis of easy magnetization in a direction perpendicular to the film surface, capable of recording information by heating said layer with irradiation of high-thermal energy and reading out said recorded information by magnetooptical effect which comprises a ternary alloy of the formula: Tb.sub.y (Fe.sub.1-x Co.sub.x).sub.1-y wherein 0.01≦x≦0.7 0.1≦y≦0.4 and having a curie temperature of at least about 100° C.
Claim 2
Dependent Claim
73 words
A magnetoopical recording medium comprising a recording layer of an amorphos alloy having an axis of easy magnetization in a direction perpendicular to the film surface, capable of recording information by heating said layer with irradiation of high-thermal energy and reading out said recorded information by magnetooptical effect which comprises a ternary alloy of the formula: Tb.sub.y (Fe.sub.1-x Co.sub.x).sub.1-y wherein 0.01≦x≦0.7 0.1≦y≦0.4 and having a curie temperature of at least about 100° C.
Claim 3
Dependent Claim
32 words
A magnetooptical recording medium according to claim 1 wherein the ternary amorphous magnetic alloy has a composition represented by the formula: Tby(Fe.sub.1-x Co.sub.x)1-y where ##EQU3## when < x≦0.375 0.1≦y≦0.2-0.064 (x-0.375) when 0.375<x<1.
Claim 4
Dependent Claim
33 words
A magnetooptical recording medium according to claim 1, wherein the amount of Co atom in the alloy is 1 atomic % or more based on the total amount of Co and Fe atoms.
Claim 5
Dependent Claim
33 words
A magnetooptical recording medium according to claim 2, wherein the amount of Co atom in the alloy is 1 atomic % or more based on the total amount of Co and Fe atoms.
Claim 6
Dependent Claim
33 words
A magnetooptical recording medium according to claim 1, wherein the amount of Co atom in the alloy is 30 atomic %-70 atomic % based on the total amount of Co and Fe atoms.
Claim 7
Dependent Claim
33 words
A magnetooptical recording medium according to claim 2, wherein the amount of Co atom in the alloy is 30 atomic %-70 atomic % based on the total amount of Co and Fe atoms.
Claim 8
Dependent Claim
33 words
A magnetooptical recording medium according to claim 5, wherein the amount of Co atom in the alloy is 40 atomic %-60 atomic % based on the total amount of Co and Fe atoms.
Claim 9
Dependent Claim
33 words
A magnetooptical recording medium according to claim 6, wherein the amount of Co atom in the alloy is 40 atomic %-60 atomic % based on the total amount of Co and Fe atoms.
Claim 10
Dependent Claim
23 words
A magnetooptical recording medium according to claim 1, wherein the film thickness of the ternary amorphous magnetic alloy is 100 Å or more.
Claim 11
Dependent Claim
23 words
A magnetooptical recording medium according to claim 2, wherein the film thickness of the ternary amorphous magnetic alloy is 100 Å or more.
Claim 12
Dependent Claim
31 words
A magnetooptical recording medium according to claim 1, wherein the ternary amorphous magnetic alloy has a composition represented by the formula: Tby(Fe.sub.1-x Co.sub.x)1-y where ##EQU4## when < x≦0.3 0.3≦y≦0.4 when 0.3<x<1.
Claim 13
Dependent Claim
32 words
A magnetooptical recording medium according to claim 11, wherein the amount of Co atom in the alloy is 1 atomic % or more based on the amount of Co and Fe atoms.
Claim 14
Dependent Claim
32 words
A magnetooptical recording medium according to claim 11, wherein the amount of Co atom in the alloy is 30 atomic %-70 atomic % based on a amount of Co and Fe atoms.
Claim 15
Dependent Claim
32 words
A magnetooptical recording medium according to claim 13, wherein the amount of Co atom in the alloy is 40 atomic %-60 atomic % based on the amount of Co and Fe atoms.
Claim 16
Dependent Claim
23 words
A magnetooptical recording medium according to claim 11, wherein the film thickness of the ternary amorphous magnetic alloy is 100 Å or more.
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) | 1990-06-01 | 1990-12-01 | 1991-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-01 | 1994-12-01 | 1995-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-01 | 1998-12-01 | 1999-06-02 | $7700.00 | Window Closed / Lapsed |