Patent US3804754A successfully refreshed from Google Patents.
US3804754A
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US
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Membrane separation process
Assignee: Daicel Corp
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Filing: 1972-08-21
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Granted: 1974-04-16
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Expires: 1992-08-21
Abstract
Abstract A SURFACTANT IS ADDED TO AN AQUEOUS PROTEIN SOLUTION UNDERGOING PURIFICATION OR CONCENTRATION USING A SEMIPERMEABLE MEMBRANE, IN ORDER TO IMPROVE THE WATER PERMEATION RATE OF THE MEMBRANE.
Inventors
- 👤 Y Ishiguro
- 👤 K Ishii
- 👤 S Konomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:37
CPC Classifications
A; A23; A23J; A23J1/00; A23J1/20; A23J1/205; A23C; A23C9/00; A23C9/14; A23C9/142; A23C9/1427; A23J1/001; A23J1/002; A23J1/08; B; B01; B01D; B01D61/00; B01D61/02; B01D61/025; B01D65/00; B01D65/08; A23V; A23V2002/00; B01D2321/00; B01D2321/16; B01D2321/168
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) | 1977-04-15 | 1977-10-15 | 1978-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-15 | 1981-10-15 | 1982-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-15 | 1985-10-15 | 1986-04-16 | $7700.00 | Window Closed / Lapsed |