US3824299A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Simplified process for manufacturing cellulose acetate reverse osmosis membranes
Assignee: Eastman Technology Inc
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Filing: 1972-01-06
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Granted: 1974-07-16
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Expires: 1992-01-06
Abstract
Abstract CELLULOSE ACETATE "REVERSE OSMOSIS" MEMBRANES HAVING EXCELLENT "FLUX" AND "REJECTION" PROPERTIES IF (A) FORMIC ACID CO FACTURED VIA A SIMPLIFED PROCESS ID (A) FORMIC ACID CONSTITUTES THE ORGANIC FRACTION OF THE SOLVENT PORTION OF THE FORMULATION FROM WHICH THE MEMBRANE IS MANUFACTURED, AND (B) A VERY HOT (>100*F.) INITIAL AQUEOUS QUENCH STEPIS UTILIZED IN THE MANUFACTURING PROCESS.
Inventors
- 👤 B Brown
- 👤 E Ray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:22
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/08; B01D71/12; B01D71/14; B01D71/16; B01D67/00; B01D67/0002; B01D67/0009; B01D67/0016; B01D67/00165; B29; B29C; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/25; B29C48/88; B29C48/911; B29C48/9135; B29C48/919; 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)
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) | 1977-07-15 | 1978-01-14 | 1978-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-15 | 1982-01-14 | 1982-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-15 | 1986-01-14 | 1986-07-16 | $7700.00 | Window Closed / Lapsed |