Patent US2948637A successfully refreshed from Google Patents.
US2948637A
Expired / Lapsed
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Process of sulfonating a plasticized polyvinyl chloride film to form a cation permselective membrane
Assignee: National Research Development Corp UK
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Filing: 1957-12-23
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Granted: 1960-08-09
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Expires: 1977-12-23
Abstract
No abstract record available.
Inventors
- 👤 Hookway Harry Thurston
- 👤 Wick Hampton
- 👤 Hale Douglas Knight
- 👤 Goldsmith Richard George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:30
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2218; C08J5/2231; C08J5/2243; C08J2327/00; C08J2327/02; C08J2327/04; C08J2327/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
106 words
A PROCESS FOR THE PREPARATION OF CATION-PERMSELECTIVE MEMBRANES WHICH COMPRISES TREATING WITH A SULPHONATING AGENT SELECTED FROM THE CLASS CONSISTING OF CHLOROSULPHONIC ACID AND MIXTURES THEREOF WITH SULPHURIC ACID, SULPHUR TRIOXIDE AND SULPHURYL CHLORIDE, A MEMBRANE OF A MATERIAL SELECTED FROM THE CLASS CONSISTING OF VINYL CHLORIDE POLYMERS AND COPOLYMERS WHICH HAVING BEEN TREATED WITH AN AGENT THAT FAVORS THE DESIRED SULPHONATION REACTION, SAID LAST MENTIONED AGENT BEING PRESENT TO THE EXTENT OF FROM 10 TO 60 PARTS PER 100 PARTS BY WEIGHT OF SAID MEMBRANE MATERIAL AND CONSISTING OF A SUBSTANCE HAVING AT LEAST ONE OF THE ACTIONS SWELLING AND PLASTICIZING UPON SAID MEMBRANE MATERIAL.
Claim 2
Dependent Claim
106 words
A PROCESS FOR THE PREPARATION OF CATION-PERMSELECTIVE MEMBRANES WHICH COMPRISES TREATING WITH A SULPHONATING AGENT SELECTED FROM THE CLASS CONSISTING OF CHLOROSULPHONIC ACID AND MIXTURES THEREOF WITH SULPHURIC ACID, SULPHUR TRIOXIDE AND SULPHURYL CHLORIDE, A MEMBRANE OF A MATERIAL SELECTED FROM THE CLASS CONSISTING OF VINYL CHLORIDE POLYMERS AND COPOLYMERS WHICH HAVING BEEN TREATED WITH AN AGENT THAT FAVORS THE DESIRED SULPHONATION REACTION, SAID LAST MENTIONED AGENT BEING PRESENT TO THE EXTENT OF FROM 10 TO 60 PARTS PER 100 PARTS BY WEIGHT OF SAID MEMBRANE MATERIAL AND CONSISTING OF A SUBSTANCE HAVING AT LEAST ONE OF THE ACTIONS SWELLING AND PLASTICIZING UPON SAID MEMBRANE MATERIAL.
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) | 1963-08-09 | 1964-02-08 | 1964-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-08-09 | 1968-02-08 | 1968-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-08-09 | 1972-02-08 | 1972-08-09 | $7700.00 | Window Closed / Lapsed |