Patent US3731161A successfully refreshed from Google Patents.
US2443420A
Expired / Lapsed
US
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Synthesis of nitriles
Assignee: EIDP Inc
•
Filing: 1946-02-21
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Granted: 1948-06-15
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Expires: 1966-02-21
Abstract
No abstract record available.
Inventors
- 👤 William F Gresham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:39
CPC Classifications
C; C07; C07C; C07C255/00
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-06-15 | 1951-12-15 | 1952-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-06-15 | 1955-12-15 | 1956-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-06-15 | 1959-12-15 | 1960-06-15 | $7700.00 | Window Closed / Lapsed |