Patent US171224A successfully refreshed from Google Patents.
Patent US3634209A successfully refreshed from Google Patents.
US3634209A
Expired / Lapsed
US
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Electro deposited magnetic films
Assignee: Ampex Corp
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Filing: 1969-07-15
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Granted: 1972-01-11
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Expires: 1989-07-15
Abstract
Abstract A process for improving the quality of a main magnetic film formed on a thick conductive substrate wherein a thin, fine grain, magnetic smoothing film of nickel-phosphorus is first deposited on the substrate and then the main magnetic film is formed on the smoothing film. The product formed comprises at least one main magnetic film formed on a thin fine grain, magnetic nickel-phosphorus smoothing layer. The main magnetic film is at least three times as thick as the smoothing layer. The smoothing layer contains from 0.5 to 8 percent phosphorus with the balance nickel.
Inventors
- 👤 Irving William Wolf
- 👤 Roberta A Woody
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:29
CPC Classifications
B; B82; B82Y; B82Y25/00; H; H01; H01F; H01F41/00; H01F41/14; H01F41/30; H01F41/302; H01F41/309; B82Y40/00; C; C25; C25D; C25D3/00; C25D3/02; C25D3/56; C25D3/562; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/925; Y10S428/9265; Y10S428/928; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535
Claims Analysis
Total Claims: 0
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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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |