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US4873033A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the production of hyperfiltration membranes

Assignee: Individual
•
Filing: 1988-06-22
•
Granted: 1989-10-10
•
Expires: 2008-06-22
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Abstract

Abstract The invention relates to a hyperfiltration membrane containing a supporting layer and a separation layer. The membrane is characterized in that the separation layer consists of a crosslinked monomolecular film of molecules, the molecules of the separation layer in the uncrosslinked state being surfactants or surfactant-like lipoids containing at least one hydrophobic chain and at least one hydrophilic group, the hydrophobic chains of these molecules being oriented mainly perpendicularly to the plane of the membrane and parallel to the diffusion direction after crosslinking and the molecules of the separation layer being crosslinked with one another through functional groups in at least one of their hydrophobic chains and/or through functional groups in at least one of their hydrophilic groups. The invention also relates to a process for the production of hyperfiltration membranes in which the surfactant molecules or the surfactant-like lipoid molecules are spread out under a certain spreading pressure or occupying an average space over the surface of an aqueous solution or at the interface between an aqueous solution and a liquid immiscible therewith, the surfactant molecules or the surfactant-like lipoid molecules are crosslinked with one another and the separation layer crosslinked in this way is applied to a supporting membrane.

Inventors

  • 👤 Klaus Heckmann
  • 👤 Georg Manecke
  • 👤 Beate Pfannenmuller
  • 👤 Klaus Ring
  • 👤 Helmut Ringsdorf

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:32
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/12; B01D69/122; B01D71/00; B01D71/06; B01D71/44; Y; Y10; Y10S; Y10S264/00; Y10S264/18

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 173 words
A method for producing a filtration membrane comprising a separation layer comprising at least one crosslinked monomolecular film formed from a surfactant each molecule of which contains at least one hydrophobic chain and at least one hydrophilic group, said separation layer being supported by a porous, mechanically stable supporting layer, which comprises: spreading said surfactant dissolved in a volatile or water soluble solvent upon the surface of an aqueous medium, or at the interface of an aqueous medium and a liquid immiscible therewith, to form a film the molecules of which have a predetermined average distance between each other obtained either by compressing said film to a predetermined pressure or by spreading a predetermined quantity of said surfactant within a predetermined area; crosslinking molecules of said surfactant through polymerizable or condensable groups in at least one of their hydrophobic chains or at least one of their hydrophylic groups to form a crosslinked film; and applying said crosslinked film constituting said separation layer to a mechanically stable supporting layer to form said filtration membrane.
Claim 2
Independent Claim 173 words
A method for producing a filtration membrane comprising a separation layer comprising at least one crosslinked monomolecular film formed from a surfactant each molecule of which contains at least one hydrophobic chain and at least one hydrophilic group, said separation layer being supported by a porous, mechanically stable supporting layer, which comprises: spreading said surfactant dissolved in a volatile or water soluble solvent upon the surface of an aqueous medium, or at the interface of an aqueous medium and a liquid immiscible therewith, to form a film the molecules of which have a predetermined average distance between each other obtained either by compressing said film to a predetermined pressure or by spreading a predetermined quantity of said surfactant within a predetermined area; crosslinking molecules of said surfactant through polymerizable or condensable groups in at least one of their hydrophobic chains or at least one of their hydrophylic groups to form a crosslinked film; and applying said crosslinked film constituting said separation layer to a mechanically stable supporting layer to form said filtration membrane.
Claim 3
Dependent Claim 34 words
A method according to claim 1 in which a porous gel is introduced into the pores of the supporting layer to form a gel layer and the surfactant film applied to said gel layer.
Claim 4
Dependent Claim 31 words
A method according to claim 2 in which one or both of the supporting layer and the gel layer contain reactive groups crosslinkable with said surfactant molecules or with each other.
Claim 5
Dependent Claim 19 words
A method according to claim 1 in which the supporting layer contains reactive groups crosslinkable with said surfactant molecules.
Claim 6
Dependent Claim 27 words
A method according to claim 1 in which said film is first applied to the supporting layer and the molecules of said surfactant then subjected to crosslinking.
Claim 7
Independent Claim 164 words
A method for producing a filtration membrane comprising a separation layer comprising at least one crosslinked monomolecular film formed from a surfactant each molecule of which contains at least one hydrophobic chain and at least one hydrophilic group, said separation layer being supported by a porous mechanically stable supporting layer, which comprises: spreading said surfactant dissolved in a volatile or water soluble solvent upon the surface of an aqueous medium, or at the interface of an aqueous medium and a liquid immiscible therewith, to form a film the molecules of which have a predetermined average distance between each other obtained either by compressing said film to a predetermined pressure or by spreading a predetermined quantity of said surfactant within a predetermined area; completely immersing a hydrophobically coated glass plate in said film to deposit the latter thereon; subjecting said deposited film to crosslinking; removing the crosslinked film from said coated glass plate and applying it to a supporting layer to form the filtration membrane.
Claim 8
Independent Claim 164 words
A method for producing a filtration membrane comprising a separation layer comprising at least one crosslinked monomolecular film formed from a surfactant each molecule of which contains at least one hydrophobic chain and at least one hydrophilic group, said separation layer being supported by a porous mechanically stable supporting layer, which comprises: spreading said surfactant dissolved in a volatile or water soluble solvent upon the surface of an aqueous medium, or at the interface of an aqueous medium and a liquid immiscible therewith, to form a film the molecules of which have a predetermined average distance between each other obtained either by compressing said film to a predetermined pressure or by spreading a predetermined quantity of said surfactant within a predetermined area; completely immersing a hydrophobically coated glass plate in said film to deposit the latter thereon; subjecting said deposited film to crosslinking; removing the crosslinked film from said coated glass plate and applying it to a supporting layer to form the filtration membrane.
Claim 9
Dependent Claim 27 words
A method according to claim 6 in which the coated glass plate with the deposited surfactant film is immersed in polymer and subjected to a crosslinking environment.
Claim 10
Dependent Claim 13 words
A method according to claim 7 in which the polymer is polyvinyl alcohol.
Claim 11
Independent Claim 150 words
A method for producing a filtration membrane comprising a separation layer comprising at least one crosslinked monomolecular film formed from a surfactant each molecule of which contains at least one hydrophobic chain and at least one hydrophylic group, said separation layer being supported by a porous mechanically stable supporting layer, which comprises: spreading said surfactant dissolved in a volatile or water soluble solvent upon the surface of an aqueous medium, or at the interface of an aqueous medium and a liquid immiscible therewith, to form a film the molecules of which have a predetermined average distance between each other obtained either by compressing film to a predetermined pressure or by spreading a predetermined quantity of said surfactant within a predetermined area; completely immersing a hollow porous polymeric fiber in said film to deposit the latter thereon; and subjecting the film-deposited fiber to a crosslinking environment to form the filtration membrane.
Claim 12
Independent Claim 150 words
A method for producing a filtration membrane comprising a separation layer comprising at least one crosslinked monomolecular film formed from a surfactant each molecule of which contains at least one hydrophobic chain and at least one hydrophylic group, said separation layer being supported by a porous mechanically stable supporting layer, which comprises: spreading said surfactant dissolved in a volatile or water soluble solvent upon the surface of an aqueous medium, or at the interface of an aqueous medium and a liquid immiscible therewith, to form a film the molecules of which have a predetermined average distance between each other obtained either by compressing film to a predetermined pressure or by spreading a predetermined quantity of said surfactant within a predetermined area; completely immersing a hollow porous polymeric fiber in said film to deposit the latter thereon; and subjecting the film-deposited fiber to a crosslinking environment to form the filtration membrane.
Claim 13
Dependent Claim 13 words
A method according to claim 9 in which said polymeric fiber is polypropylene.

References Cited (Backward Citations)

US3129146A Cited
US3593855A Cited
US3780147A Cited
DE2420846A1 Cited
US4279855A Cited
US3892665A Cited
DE2557355A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-10-09 1993-04-10 1993-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-10-09 1997-04-10 1997-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-10-09 2001-04-10 2001-10-10 $7700.00 Window Closed / Lapsed

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