US3625849A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of magnetic medium
Assignee: International Business Machines Corp
•
Filing: 1969-09-24
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Granted: 1971-12-07
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Expires: 1989-09-24
Abstract
Abstract To make a magnetic record medium having high coercivity and low magnetostriction, an alloy consisting of a magnetic component and nonmagnetic component in a solid solution is applied by cathode sputtering to a nonmagnetic carrier, which is supported by a holder maintained at room temperature. The applied coating is heated at a temperature greater than 200* C. for more than 1 hour within an inert gas atmosphere, the assembly being annealed at a temperature of approximately 600* C.
Inventors
- 👤 Dietrich R Rogalla
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:35
CPC Classifications
H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/12; H01F10/14
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
17 words
A method as in claim 1, wherein the coating step is accomplished by means of cathode sputtering.
Claim 2
Dependent Claim
24 words
A method as in claim 1, wherein the step of heating is accomplished at a temperature between 500*-600* C. for approximately 2 1/4 hours.
Claim 3
Dependent Claim
23 words
A method as in claim 1, wherein the magnetic component of the alloy is less than or equal to 50 percent by volume.
Claim 4
Dependent Claim
22 words
A method as in claim 1, wherein the alloy is taken from the group consisting of cobalt-copper, cobalt-gold, iron-copper, iron-gold, and nickel-gold.
References Cited (Backward Citations)
US2900282A
Cited
US3433721A
Cited
US3202538A
Cited
US3396047A
Cited
US3480922A
Cited
US3475309A
Cited
US3516860A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-06 | 1975-06-07 | 1975-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-06 | 1979-06-07 | 1979-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-06 | 1983-06-07 | 1983-12-07 | $7700.00 | Window Closed / Lapsed |