Patent US2678307A successfully refreshed from Google Patents.
US2678307A
Expired / Lapsed
US
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Carboxysulfonsc cation-exchange
Assignee: —
•
Filing: —
•
Granted: 1954-05-11
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Expires: 1971-05-11
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:42
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/34; B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/20; C08F8/12; C08F8/36; C08F8/44; C08L; C08L41/00; C08F2800/00; C08F2800/20
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
67 words
A PROCESS FOR PREPARING AN INSOLUBLE, CATIONEXCHANGE RESIN CONTAINING SULFONIC ACID GROUPS AND CARBOXYL GROUPS AS ITS FUNCTIONAL, CATIONADSORBING GROUPS, WHICH COMPRISES SULFONATING AT A TEMPERATURE OF ABOUT 80* C. TO ABOUT 100* C. AND THEREAFTER HYDROLYZING AN INSOLUBLE, CROSSLINKED COPOLYMER OF A MIXTURE OF (A) METHYL METHACRYLATE AND (B) DIVINYLBENZENE, SAID DIVINYLBENZENE BEING COPOLYMERIZED IN AN AMOUNT EQUAL TO 3 TO 15% ON A MOLAR BASIS.
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) | 1957-05-10 | 1957-11-09 | 1958-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-05-10 | 1961-11-09 | 1962-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-05-10 | 1965-11-09 | 1966-05-11 | $7700.00 | Window Closed / Lapsed |