Patent US2131994A successfully refreshed from Google Patents.
US2131994A
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Refractory metal composition
Assignee: Duracell Inc USA
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Filing: 1935-08-13
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Granted: 1938-10-04
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Expires: 1955-08-13
Abstract
No abstract record available.
Inventors
- 👤 Franz R Hensel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:09
CPC Classifications
C; C22; C22C; C22C29/00; C22C29/02; C22C29/06; C22C29/08; C22C27/00; C22C27/04; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/929; Y10T; Y10T428/00; Y10T428/12; Y10T428/12007
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) | 1941-10-03 | 1942-04-04 | 1942-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-10-03 | 1946-04-04 | 1946-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-10-03 | 1950-04-04 | 1950-10-04 | $7700.00 | Window Closed / Lapsed |