Patent US3563889A successfully refreshed from Google Patents.
US3563889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integral semipermeable membrane and braided support tube
Assignee: Kovalus Separation Solutions LLC
•
Filing: 1969-01-03
•
Granted: 1971-02-16
•
Expires: 1989-01-03
Abstract
Abstract AN INTEGRALLY SUPPORTED SEMIPERMEABLE MEMBRANE IS COMPOSED OF A TUBULAR BRAIDED FABRIC IMPREGNATED WITH A POLYMERIC FILM FORMING COMPOSITIONS, AND CARRIES ON AT LEAST ONE SURFACE A LAYER OF THE POLYMER WITH THE SURFACE OF THE POLYMER CARRYING AN ACTIVE LAYER WHICH PROVIDES THE SEPARATION CHARACTERISTICS OF THE MEMBRANE.
Inventors
- 👤 William W Cooper
- 👤 Russell W Pierce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:36
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/10; B01D69/107; B01D69/1071
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |