Tubular membrane and membrane support manufacturing process
Abstract
Abstract Reverse osmosis tubes, and a method for forming them including the steps of: wrapping a porous paper strip about a mandrel; sealing the porous paper strip at its edges to form a porous paper tube; moving the porous paper tube along the mandrel; winding resin-impregnated glass fibers over the outer surface of the moving tube to produce a porous glass fiber coating; heating the glass fiber coating to cure the resin as it moves with the tube; cooling the glass fiber coating; coating the inner surface of the moving porous paper tube with a thin layer of reverseosmosis-membrane-forming solution; drawing a slight vacuum around the outer surface of the porous glass fiber coating in an area overlapping the axial position where the membrane-forming solution is applied, causing the membrane-forming solution to closely adhere to the inner surface of the porous paper tube; and, immersing the coated porous paper tube in a gelation bath to gel the film to a useable membrane state.
Inventors
- 👤 Murray Marks
- 👤 Harry A King
- 👤 Paul A Longwell
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |