Patent US1946667A successfully refreshed from Google Patents.
US1946667A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of furfural
Assignee: A HEYMAN AB
•
Filing: 1930-08-21
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Granted: 1934-02-13
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Expires: 1950-08-21
Abstract
No abstract record available.
Inventors
- 👤 Blomqvist Georg Henning
- 👤 Groth Bertil Sixten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:53
CPC Classifications
C; C07; C07D; C07D307/00; C07D307/02; C07D307/34; C07D307/38; C07D307/40; C07D307/46; C07D307/48; C07D307/50
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) | 1937-02-12 | 1937-08-14 | 1938-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1941-02-12 | 1941-08-14 | 1942-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1945-02-12 | 1945-08-14 | 1946-02-13 | $7700.00 | Window Closed / Lapsed |