Patent US2137988A successfully refreshed from Google Patents.
US2137988A
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US
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Adherent aluminum compound
Assignee: Heresite and Chemical Co
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Filing: 1936-10-21
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Granted: 1938-11-22
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Expires: 1956-10-21
Abstract
No abstract record available.
Inventors
- 👤 Charles H Hempel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:51
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/48; C23C22/56
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) | 1941-11-21 | 1942-05-23 | 1942-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-11-21 | 1946-05-23 | 1946-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-11-21 | 1950-05-23 | 1950-11-22 | $7700.00 | Window Closed / Lapsed |