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US3471590A
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Synthetic fiber-forming polyamides containing piperazine polyamides
Assignee: EIDP Inc
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Filing: 1967-05-03
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Granted: 1969-10-07
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Expires: 1987-05-03
Abstract
No abstract record available.
Inventors
- 👤 Emerson L Wittbecker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:40
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/26; D; D01; D01F; D01F6/00; D01F6/88; D01F6/90
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3216965A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-10-06 | 1973-04-07 | 1973-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-06 | 1977-04-07 | 1977-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-06 | 1981-04-07 | 1981-10-07 | $7700.00 | Window Closed / Lapsed |