US3526608A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Use of polyamides derived from iminodiacetic acid and related compounds in improving the wet and dry strength of paper
Assignee: Pfizer Inc
•
Filing: 1968-02-13
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Granted: 1970-09-01
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Expires: 1988-02-13
Abstract
No abstract record available.
Inventors
- 👤 Rudolph G Berg
- 👤 Bryce E Tate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:35
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/54; D21H17/55; C; C08; C08G; C08G69/00; C08G69/48
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-08-31 | 1974-03-02 | 1974-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-08-31 | 1978-03-02 | 1978-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-08-31 | 1982-03-02 | 1982-09-01 | $7700.00 | Window Closed / Lapsed |