US1993681A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of diolefines from hydrocarbon mixtures
Assignee: Carbide and Carbon Chemicals Corp
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Filing: 1931-04-24
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Granted: 1935-03-05
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Expires: 1951-04-24
Abstract
No abstract record available.
Inventors
- 👤 Granville A Perkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:27
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/17
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) | 1938-03-04 | 1938-09-03 | 1939-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1942-03-04 | 1942-09-03 | 1943-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1946-03-04 | 1946-09-03 | 1947-03-05 | $7700.00 | Window Closed / Lapsed |