US3660338A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amphoteric strengthening agents for paper
Assignee: Wyeth Holdings LLC
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Filing: 1969-07-22
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Granted: 1972-05-02
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Expires: 1989-07-22
Abstract
Abstract NORMALLY LIQUID WATER-INSOLUBLE POLYSALT COACERVATES, WHEREIN ONE OF THE COMPONENT POLYMERS IS ONLY WEAKLY IONIC, ARE WATER-SOLUBLE WHERE THEY CONTAIN A SUFFICIENT AMOUNT OF AN IONIZATION SUPPRESSOR.
Inventors
- 👤 Peter Economou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:28
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/41; D21H17/42; D21H17/43; C; C08; C08J; C08J3/00; C08J3/24; C08J3/246; C08L; C08L77/00; C08L79/00; C08L79/02; C08L81/00; C08L81/08
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) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |