Patent US3792135A successfully refreshed from Google Patents.
US3792135A
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Process for manufacturing cellulosic reverse osmosis membranes using a very high temperature initial aqueous quench
Assignee: Eastman Technology Inc
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Filing: 1972-01-06
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Granted: 1974-02-12
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Expires: 1992-01-06
Abstract
Abstract IMPROVED PROCESSES ARE DISCLOSED FOR MANUFACTURING CELLULOSIC "REVERSE OSMOSIS" MEMBRANES, WHICH PROCESSES INVOLVE THE UTILIZATION OF A VERY HOT INITIAL QUENCH BATH, IN COMBINATION WITH DOPE COMPOSITIONS THAT CONTAIN ACETIC ACID, FORMIC ACID OR MIXTURES THEREOF, EITHER WITH OR WITHOUT OTHER ORGANIC SOLVENTS.
Inventors
- 👤 B Brown
- 👤 E Ray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:34
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0002; B01D67/0009; B01D71/00; B01D71/06; B01D71/08; B01D71/12; B01D71/14; B01D61/00; B01D61/02; B01D61/025; Y; Y02; Y02A; Y02A20/00; Y02A20/124; Y02A20/131
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |