US2433227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of lignin substances
Assignee: Sulphite Products Corp
•
Filing: 1944-05-17
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Granted: 1947-12-23
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Expires: 1964-05-17
Abstract
No abstract record available.
Inventors
- 👤 Harry F Lewis
- 👤 Irwin A Pearl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:39
CPC Classifications
C; C08; C08H; C08H6/00; C07; C07C; C07C45/00; C07C45/78
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2057117A
Cited
US2296952A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-12-22 | 1951-06-23 | 1951-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-12-22 | 1955-06-23 | 1955-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-12-22 | 1959-06-23 | 1959-12-23 | $7700.00 | Window Closed / Lapsed |