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Patent US4803129A successfully refreshed from Google Patents.
US4803129A
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US
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Magnetic recording material
Assignee: Yamaha Corp
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Filing: 1987-12-14
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Granted: 1989-02-07
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Expires: 2007-12-14
Abstract
Abstract In composition of Tb-Fe-Co type magnetooptic recording material, additional inclusion of specified amount of Be much improves corrosion resistance and Kerr rotation angle of a magnetooptic disc made therefrom.
Inventors
- 👤 Naoshi Noriai
- 👤 Tadao Tokushima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:01
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; G11B11/10589; G11B11/10593; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
An improved magnetooptic recording material comprising a composition defined by {(Fe.sub.a Co.sub.b).sub.c Tb.sub.d }.sub.e Be.sub.f Ti.sub.g Al.sub.h in which a to h indicate atomic ratios, and a is in a range from 0.3 to 0.95, b is in a range from 0.05 to 0.7, C is in a range from 0.6 to 0.8, d is in a range from 0.2 to 0.4, e is in a range from 0.80 to 0.99, f is in a range from 0.01 to 0.20, g is in a range from 0.01 to 0.20 and h is in a range from 0.01 to 0.20.
Claim 2
Dependent Claim
99 words
An improved magnetooptic recording material comprising a composition defined by {(Fe.sub.a Co.sub.b).sub.c Tb.sub.d }.sub.e Be.sub.f Ti.sub.g Al.sub.h in which a to h indicate atomic ratios, and a is in a range from 0.3 to 0.95, b is in a range from 0.05 to 0.7, C is in a range from 0.6 to 0.8, d is in a range from 0.2 to 0.4, e is in a range from 0.80 to 0.99, f is in a range from 0.01 to 0.20, g is in a range from 0.01 to 0.20 and h is in a range from 0.01 to 0.20.
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) | 1992-02-07 | 1992-08-08 | 1993-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-07 | 1996-08-08 | 1997-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-07 | 2000-08-08 | 2001-02-07 | $7700.00 | Window Closed / Lapsed |