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US3743595A
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Dual-layer hyperfiltration membrane and process for using same
Assignee: United States Atomic Energy Commission
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Filing: 1971-04-20
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Granted: 1973-07-03
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Expires: 1991-04-20
Abstract
Abstract DUAL-LAYER HYPERFILTRATION MEMBRANES MADE BY COATING A HYDROUS OXIDE MEMBRANE WITH AN AORGANIC POLYACID SUCH AS POLYACRYLIC ACID FOLLOWED BY AN ACID WASH BEHAVE MORE REPRODUCIBLY THAN POLYACID MEMBRANCES FORMED IN THE ABSENCE OF THE HYDROUS OXIDE AND, UNLIKE HYDROUS OXIDE MEMBRANES, OPERATE BEST IN THE PH RANGE MOST COMMONLY FOUND IN SALINE WATERS.
Inventors
- 👤 J Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:14
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/14
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) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |