Patent US3556305A successfully refreshed from Google Patents.
US3556305A
Expired / Lapsed
US
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Composite membrane and process for making same
Assignee: Amicon Corp
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Filing: 1968-03-28
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Granted: 1971-01-19
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Expires: 1988-03-28
Abstract
Abstract A novel membrane suitable for use in reverse osmosis and related separation processes, said membrane comprising (a) an anisotropic membrane comprising a thin microporous barrier skin and a thicker macroporous support layer, (b) a very thin layer of a film forming adhesive polymer over the barrier skin of hydraulically porous substrate and (c) a very thin diffusive type membrane film overlying said adhesive polymer and bound to said porous substrate by said adhesive polymer.
Inventors
- 👤 Jacob Shorr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:41
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/14; B01D69/12; B01D69/1214; B01D69/1216; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249978; Y10T428/24998; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/31504; Y10T428/31855
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
17 words
an adhesive polymeric layer having a maximum thickness of about 1,500 angstroms coated on said substrate; and
Claim 2
Dependent Claim
20 words
A membrane as defined in claim 1 wherein the maximum thickness of said adhesive polymeric layer is about 500 angstroms.
Claim 3
Dependent Claim
20 words
A membrane as defined in claim 1 wherein said adhesive layer consists of an alkyl vinyl ether polymer or copolymer.
Claim 4
Dependent Claim
19 words
a diffusive polymer or gellike film bonded to said barrier layer of said porous substrate by said adhesive layer.
Claim 5
Dependent Claim
31 words
A membrane as defined in claim 1 wherein said diffusive film is polyvinyl alcohol or a mixture of polyvinyl methyl ether with a copolymer of methyl vinyl ether with maleic anhydride.
Claim 6
Dependent Claim
28 words
A membrane as defined in claim 1 wherein the composite thickness of said adhesive layer and a diffusive film overlying said layer is less than about 2 microns.
Claim 7
Dependent Claim
17 words
A membrane as defined in claim 1 wherein said porous substrate is formed of a polysulfone polymer.
Claim 8
Dependent Claim
126 words
A process for making a membrane suitable for use in ultrafiltration, reverse osmosis, and other such separation processes which coMprises providing a porous substrate formed of a highly anisotropic polymeric membrane having a. a barrier layer at one surface thereof comprising micropores from 15 to 1,000 angstroms in diameter and having a thickness from about 0.1 to 5 microns and b. a macroporous support layer, coating said substrate with a solution of an adhesive polymer to thereby deposit on the surface of the substrate an adhesive polymeric layer having a maximum thickness of about 1,500 angstroms, and filtering through said substrate from the surface having the barrier layer a dilute solution of polymer or gellike material to form a diffusive film bonded to said adhesive layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |