Patent US3636150A successfully refreshed from Google Patents.
US3636150A
Expired / Lapsed
US
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Process for preparing cellulose ester reverse osmosis membranes on flexible webs having enhanced releasability
Assignee: Eastman Kodak Co
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Filing: 1969-11-28
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Granted: 1972-01-18
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Expires: 1989-11-28
Abstract
Abstract IT HAS BEEN FOUND THAT WHEN FLEXIBLE WEBS (SUCH AS THOSE OF POLYMERIC FILMS HAVING GOOD DIMEMSIONABLE STABILITY AND SUBSTANTIALLY NO SOLUBILITY IN THE DOPE SYSTEMS BEING USED) ARE UTILIZED AS TEMPORARY SUPPORTS UPON WHICH CELLULOSE ESTER DOPE SOLUTIONS ARE CAST IN THE MANUFACTURE OF "REVERSE OSMOSIS" MEMBRANES, THE RESULTING GELLED MEMBRANES ARE ORDINARILY DIFFICULT TO REMOVE FROM THE FLEXIBLE WEB. DRAMATICALLY ENHANCED RELEASABILITY OF THE GELLED MEMBRANES FROM SUCH FLEXIBLE SUPPORTS RESULTS IF THE SURFACE OF THE FLEXIBLE SUPPORT IS FIRST MADE VERY HYDROPHYLIC.
Inventors
- 👤 Martin E Rowley
- 👤 Walter D Slowig
- 👤 Carl F Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:28
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0002; B01D67/0009; B01D67/0013; B01D69/00; B01D69/10; B01D69/105; B01D2323/00; B01D2323/02; B01D61/00; B01D61/02; B01D61/025
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) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |