US3335162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymeric impurity removal from an aqueous quaternary ammonium salt solution
Assignee: Monsanto Co
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Filing: 1965-05-10
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Granted: 1967-08-08
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Expires: 1985-05-10
Abstract
No abstract record available.
Inventors
- 👤 Charles R Campbell
- 👤 Iii Marion J Mathews
- 👤 Roland R Spiegelhalter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:51
CPC Classifications
C; C07; C07C; C07C255/00; C25; C25B; C25B3/00; C25B3/01; C25B3/09; C25B3/20; C25B3/29; C25B3/295
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
A PROCESS FOR REMOVING PARTIALLY HYDROLYZED POLYACRYLONITRILE FROM AN AQUEOUS SOLUTION OF A HYDROTROPIC QUATERNARY AMMONIUM SALT COMPRISING, IN COMBINATION, THE STEPS OF: (A)PRECIPITATING SAID POLYACRYLONITRILE BY ADJUSTING THE SALT CONCENTRATION OF SAID SOLUTION TO NOT MORE THAN ABOUT 55 WEIGHT PERCENT AND ADJUSTING THE PH OF SAID SOLUTION TO NOT MORE THAN ABOUT 7; AND (B) SEPARATING SAID POLYACRYLONITRILE FROM SAID SOLUTION.
Claim 2
Dependent Claim
63 words
A PROCESS FOR REMOVING PARTIALLY HYDROLYZED POLYACRYLONITRILE FROM AN AQUEOUS SOLUTION OF A HYDROTROPIC QUATERNARY AMMONIUM SALT COMPRISING, IN COMBINATION, THE STEPS OF: (A)PRECIPITATING SAID POLYACRYLONITRILE BY ADJUSTING THE SALT CONCENTRATION OF SAID SOLUTION TO NOT MORE THAN ABOUT 55 WEIGHT PERCENT AND ADJUSTING THE PH OF SAID SOLUTION TO NOT MORE THAN ABOUT 7; AND (B) SEPARATING SAID POLYACRYLONITRILE FROM SAID SOLUTION.
References Cited (Backward Citations)
US3193481A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-08-07 | 1971-02-06 | 1971-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-08-07 | 1975-02-06 | 1975-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-08-07 | 1979-02-06 | 1979-08-08 | $7700.00 | Window Closed / Lapsed |