US1704257A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing refractory metals
Assignee: Westinghouse Lamp Co
•
Filing: 1923-02-12
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Granted: 1929-03-05
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Expires: 1943-02-12
Abstract
No abstract record available.
Inventors
- 👤 Marden John Wesley
- 👤 Thomas Thomas Philip
- 👤 Conley John Edward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:49
CPC Classifications
C; C22; C22B; C22B60/00; C22B60/02; C22B60/0291; C22B34/00; C22B5/00; C22B5/02; C22B5/04; C22B60/0204; C22B60/0213
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) | 1932-03-04 | 1932-09-03 | 1933-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1936-03-04 | 1936-09-03 | 1937-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1940-03-04 | 1940-09-03 | 1941-03-05 | $7700.00 | Window Closed / Lapsed |