Patent US2223977A successfully refreshed from Google Patents.
US2223977A
Expired / Lapsed
US
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Introducing active metals into envelopes
Assignee: RCA Corp
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Filing: 1939-07-29
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Granted: 1940-12-03
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Expires: 1959-07-29
Abstract
No abstract record available.
Inventors
- 👤 Delos H Wamsley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:14
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/38; H01J9/395; H01J7/00; H01J7/14; H01J7/18; H01J7/183
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) | 1943-12-03 | 1944-06-03 | 1944-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-12-03 | 1948-06-03 | 1948-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-12-03 | 1952-06-03 | 1952-12-03 | $7700.00 | Window Closed / Lapsed |