Patent US2223771A successfully refreshed from Google Patents.
US2223771A
Expired / Lapsed
US
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Coining of sodium dichromate
Assignee: ECCLESTONE CHEMICAL CO Inc
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Filing: 1939-09-30
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Granted: 1940-12-03
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Expires: 1959-09-30
Abstract
No abstract record available.
Inventors
- 👤 Peter W Uhl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:44
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/18; C23F11/185; C01; C01G; C01G37/00; C01G37/14; Y; Y10; Y10S; Y10S425/00; Y10S425/101
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 |