Patent US1820141A successfully refreshed from Google Patents.
US1820141A
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US
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Process for the purification of metals
Assignee: BRITISH MAXIUM Co Ltd
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Filing: 1928-10-23
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Granted: 1931-08-25
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Expires: 1948-10-23
Abstract
No abstract record available.
Inventors
- 👤 Jessup Alfred Claude
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:36
CPC Classifications
C; C22; C22B; C22B9/00; C22B9/02; C22B7/00; C22B9/023; F; F27; F27B; F27B14/00; Y; Y02; Y02P; Y02P10/00; Y02P10/20
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) | 1934-08-24 | 1935-02-23 | 1935-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-08-24 | 1939-02-23 | 1939-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-08-24 | 1943-02-23 | 1943-08-25 | $7700.00 | Window Closed / Lapsed |