Patent US1659175A successfully refreshed from Google Patents.
US1659175A
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Electron-emitting material and the preparation thereof
Assignee: Westinghouse Lamp Co
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Filing: 1922-06-20
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Granted: 1928-02-14
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Expires: 1942-06-20
Abstract
No abstract record available.
Inventors
- 👤 Thomas Thomas Philip
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:45
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/04; H01J9/042; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/929; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12806; Y10T428/12826; Y10T428/12833
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1931-02-13 | 1931-08-15 | 1932-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-02-13 | 1935-08-15 | 1936-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-02-13 | 1939-08-15 | 1940-02-14 | $7700.00 | Window Closed / Lapsed |