US3500925A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water-flooding process for secondary oil recovery with polymeric n-vinyl lactam and metal salt to control clay swelling
Assignee: GAF Corp
•
Filing: 1967-06-06
•
Granted: 1970-03-17
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Expires: 1987-06-06
Abstract
No abstract record available.
Inventors
- 👤 John P G Beiswanger
- 👤 Andrew Stefcik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:37
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/588
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2761837A
Cited
US3020953A
Cited
US3016352A
Cited
US3179171A
Cited
US3208528A
Cited
US3294765A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-16 | 1973-09-15 | 1974-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-16 | 1977-09-15 | 1978-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-16 | 1981-09-15 | 1982-03-17 | $7700.00 | Window Closed / Lapsed |