Patent US2052490A successfully refreshed from Google Patents.
US2052490A
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US
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Method of making microporous articles
Assignee: Willard Storage Battery Co
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Filing: 1933-11-20
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Granted: 1936-08-25
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Expires: 1953-11-20
Abstract
No abstract record available.
Inventors
- 👤 Willard L Reinhardt
- 👤 Leland E Wells
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:56
CPC Classifications
H; H01; H01M; H01M50/00; H01M50/40; H01M50/403; H01M50/406; H01M50/409; H01M50/411; H01M50/414; H01M50/429; H01M50/489; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1007; Y10T156/1015
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) | 1939-08-25 | 1940-02-24 | 1940-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1943-08-25 | 1944-02-24 | 1944-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1947-08-25 | 1948-02-24 | 1948-08-25 | $7700.00 | Window Closed / Lapsed |