Patent US2230592A successfully refreshed from Google Patents.
US2230592A
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Process of preparing magnesia and sulphur dioxide
Assignee: WALTHER H DUISBERG
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Filing: 1939-09-15
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Granted: 1941-02-04
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Expires: 1959-09-15
Abstract
No abstract record available.
Inventors
- 👤 Griessbach Robert
- 👤 Bitterfeld Kreis
- 👤 Sutterlin Walther
- 👤 Zirngibl Hans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:01
CPC Classifications
C; C01; C01F; C01F5/00; C01F5/02; C01F5/06; C01F5/12; C01B; C01B17/00; C01B17/48; C01B17/50; C01B17/501
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) | 1944-02-04 | 1944-08-05 | 1945-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-02-04 | 1948-08-05 | 1949-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-02-04 | 1952-08-05 | 1953-02-04 | $7700.00 | Window Closed / Lapsed |