Patent US494161A successfully refreshed from Google Patents.
US3674728A
Expired / Lapsed
US
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Ion exchange resins
Assignee: Rohm and Haas Co
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Filing: 1970-04-30
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Granted: 1972-07-04
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Expires: 1990-04-30
Abstract
Abstract Through the use of a combination of cross-linking agents it is possible to obtain a polymer structure capable of being converted into an ion-exchange resin having improved properties. This combination of cross-linking agents comprises two compounds, one aliphatic and one aromatic, each of which has at least two double bonds.
Inventors
- 👤 Jack V Carbonnel
- 👤 Paul D Grammont
- 👤 Louis E Werotte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:33
CPC Classifications
C; C08; C08F; C08F220/00; C08F220/02; C08F220/42; C08F20/00; C08F20/02; C08F20/42; C08F212/00; C08F212/02; C08F212/04; C08F220/44; C08F36/00; C08F36/02; C08F36/20; C08F8/00
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) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |