US4242159A
Expired / Lapsed
US
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Process for the production of composite membranes
Assignee: Battelle-Institut
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Filing: 1979-02-26
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Granted: 1980-12-30
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Expires: 1999-02-26
Abstract
Abstract A process for the production of a composite membrane consisting of a porous supporting membrane and a thin separating membrane. The separating membrane is produced on the surface of a carrier film (consisting essentially of a soluble polymer). The carrier film coated with the separating membrane is placed with its separating membrane side on a porous supporting membrane such that the separating membrane is between the supporting membrane and the carrier film. The carrier film is then dissolved.
Inventors
- 👤 Albrecht Klimmek
- 👤 Wolfram Krieger
- 👤 Roland Reiner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:03
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/12; B01D69/122
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
86 words
In a process for the production of a composite membrane consisting of a porous supporting membrane and a thin separating membrane, the improvement characterized by the steps of producing a separating membrane on the surface of a carrier film consisting essentially of at least one soluble polymer, placing the carrier film having the separating membrane thereon with its separating membrane side on a porous supporting membrane such that the separating membrane is between the supporting membrane and the carrier film, and then dissolving the carrier film.
Claim 2
Dependent Claim
86 words
In a process for the production of a composite membrane consisting of a porous supporting membrane and a thin separating membrane, the improvement characterized by the steps of producing a separating membrane on the surface of a carrier film consisting essentially of at least one soluble polymer, placing the carrier film having the separating membrane thereon with its separating membrane side on a porous supporting membrane such that the separating membrane is between the supporting membrane and the carrier film, and then dissolving the carrier film.
Claim 3
Dependent Claim
73 words
Process as claimed in claim 1 wherein the carrier film contains at least one soluble polymer selected from the group consisting of polyvinyl alcohol, partially acetylated polyvinyl alcohol, polyacrylic acid, a salt of polyacrylic acid, polymethacrylic acid, a salt of polymethacrylic acid, polyvinylpyrrolidone, polyacrylamide, polyvinyl acetate, a copolymer of the aforegoing, alginic acid, a salt of alginic acid, carboxymethylcellulose, cellulose acetate, cellulose, polycarbonate, and a mixture of one or more of the aforegoing.
Claim 4
Dependent Claim
16 words
Process as claimed in claim 2 wherein the carrier film is 5 to 100 μm thick.
Claim 5
Dependent Claim
16 words
Process as claimed in claim 1 wherein the carrier film consists essentially of a water-soluble polymer.
Claim 6
Dependent Claim
16 words
Process as claimed in claim 4 wherein the carrier film is 5 to 100 μm thick.
Claim 7
Dependent Claim
16 words
Process as claimed in claim 5 wherein the carrier film is 20 to 30 μm thick.
Claim 8
Dependent Claim
26 words
Process as claimed in claim 4 wherein the carrier film contains up to 50 weight percent, related to the weight of the polymer, of a plasticizer.
Claim 9
Dependent Claim
26 words
Process as claimed in claim 7 wherein the carrier film contains 10 to 20 weight percent, related to the weight of the polymer, of a plasticizer.
Claim 10
Dependent Claim
24 words
Process as claimed in claim 7 wherein the polymer is polyvinyl alcohol and the plasticizer for the polyvinyl alcohol is polyethylene glycol or sorbite.
Claim 11
Dependent Claim
25 words
Process as claimed in claim 1 wherein the carrier film is produced from a polymeric solution to which a nonionic wetting agent has been added.
Claim 12
Dependent Claim
26 words
Process as claimed in claim 1 wherein the carrier film contains up to 50 weight percent, related to the weight of the polymer, of a plasticizer.
Claim 13
Dependent Claim
21 words
Process as claimed in claim 1 wherein the production step is achieved by coating said separating membrane on said carrier layer.
Claim 14
Dependent Claim
25 words
Process as claimed in claim 1 wherein the separating membrane is produced from a polymeric solution to which a nonionic wetting agent has been added.
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) | 1983-12-30 | 1984-06-30 | 1984-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-30 | 1988-06-30 | 1988-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-30 | 1992-06-30 | 1992-12-30 | $7700.00 | Window Closed / Lapsed |