Patent US3678922A successfully refreshed from Google Patents.
US2097120A
Expired / Lapsed
US
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Manufacture of nitrogenous cellulose derivatives
Assignee: IG Farbenindustrie AG
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Filing: 1935-08-08
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Granted: 1937-10-26
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Expires: 1955-08-08
Abstract
No abstract record available.
Inventors
- 👤 Fink Heinrich
- 👤 Bitterfeld Wolfen Kries
- 👤 Stahn Richard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:39
CPC Classifications
D; D06; D06P; D06P5/00; D06P5/22; D06P5/225
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) | 1940-10-25 | 1941-04-26 | 1941-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-10-25 | 1945-04-26 | 1945-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-10-25 | 1949-04-26 | 1949-10-26 | $7700.00 | Window Closed / Lapsed |