US2914516A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of polyvinylpyrrolidone
Assignee: GAF Chemicals Corp
•
Filing: 1956-05-07
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Granted: 1959-11-24
•
Expires: 1976-05-07
Abstract
No abstract record available.
Inventors
- 👤 Siggia Sidney
- 👤 Stahl Clarence Richard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:19
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2205184A
Cited
US2665271A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-11-23 | 1963-05-25 | 1963-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-11-23 | 1967-05-25 | 1967-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-11-23 | 1971-05-25 | 1971-11-24 | $7700.00 | Window Closed / Lapsed |