# US 10,478,785 B2 · Abrasion-proof filtration membrane and method of producing said membrane > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,478,785 B2 - Document ID: US10478785B2 - Status: Granted - Kind: B2 - Application number: 14/348,658 - Filed: 2012-10-02 - Published: 2014-09-25 - Granted: 2019-11-19 - Earliest claimed: 2011-10-04 - Assignees: MN Beteiligungs GmbH - Applicants: Mn Beteiligungs GmbH - Inventors: Gisela Jung; Andreas Bareth; Ulrich Meyer-Blumenroth - Web page: https://patentgrep.com/patent/US10478785B2 ## CPC - B01D 71/62: Polycondensates having nitrogen-containing heterocyclic rings in the main chain - B01D 67/0013: {Casting processes} - B01D 67/00165: {Composition of the coagulation baths} - B01D 69/02: characterised by their properties - B01D 71/441: {Polyvinylpyrrolidone} - B01D 71/68: Polysulfones; Polyethersulfones - B01D 65/04: with movable bodies, e.g. foam balls - B01D 2325/0283: Pore size - B01D 2325/04: Characteristic thickness - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract A filtration membrane (1) is provided that includes a porous support (4) and a membrane layer having a first and a second zone (2, 3). The first zone (2) has a thickness of 5 to 15 μm and an average pore opening size of smaller/equal 0.4 and the second zone (3) has a thickness of 5 to 40 μm and an average pore opening size of 0.5 to 5.0 μm. The filtration membrane (1) is produced by forming a single- or -double-layer coating on the porous support (4). ## Claims ### Claim 1 A filtration membrane comprising a porous support, a membrane surface for receiving feed, and a membrane layer with a first and second zone, wherein the first zone has a thickness of 5 to 15 μm and a mean pore size of less than or equal to 0.4 μm and the second zone has a thickness of 5 to 40 μm and a mean pore size of 0.4 to 5.0 μm and wherein, said support is a textile nonwoven, wherein the filtration membrane has a clean water permeability of 200 to 2000 L/(m2·h·bar). ### Claim 2 (depends on 1) The filtration membrane as claimed in claim 1, wherein the first zone has a thickness of 8 to 12 μm. ### Claim 3 (depends on 1) The filtration membrane as claimed in claim 1, wherein the first zone has a mean pore size of less than or equal to 0.3 μm. ### Claim 4 (depends on 1) The filtration membrane as claimed in claim 1, wherein the second zone has a thickness of 5 to 30 μm. ### Claim 5 (depends on 1) The filtration membrane as claimed in claim 1, wherein the second zone has a mean pore size of 0.4 to 2.0 μm. ### Claim 6 (depends on 1) The filtration membrane as claimed in claim 1, wherein in the first zone the mean pore size increases with increasing distance from said membrane surface and said first zone is placed next to said membrane surface. ### Claim 7 (depends on 6) The filtration membrane as claimed in claim 6, wherein in the second zone, the mean pore size increases with increasing distance from said membrane surface. ### Claim 8 (depends on 6) The filtration membrane as claimed in claim 6, wherein the second zone is comprised of polysulfone and polyvinylpyrrolidone. ### Claim 9 (depends on 1) The filtration membrane as claimed in claim 1, wherein said filtration membrane has, after an abrasion test lasting 450 h, a mean pore diameter of 0.05 to 0.2 μm. ### Claim 10 (depends on 1) A filtration device comprising a filtration membrane as claimed in claim 1. ### Claim 11 (depends on 1) The filtration membrane as claimed in claim 1, wherein the filtration membrane has a clean water permeability of 300 to 2000 L/(m2·h·bar). ### Claim 12 (depends on 1) The filtration membrane as claimed in claim 1, wherein the filtration membrane has a clean water permeability of 500 to 1000 L/(m2·h·bar). ### Claim 13 (depends on 4) The filtration membrane as claimed in claim 4, wherein the second zone has a thickness of 10 to 20 μm. ### Claim 14 (depends on 9) The filtration membrane as claimed in claim 9, wherein said filtration membrane has, after an abrasion test lasting 450 h, a mean pore diameter of 0.08 to 0.15 μm. ### Claim 15 (depends on 7) The filtration membrane as claimed in claim 7, wherein said second zone is placed between said first zone on one side and said porous support on the side opposite said first zone such that the porous support is placed away from said membrane surface. ### Claim 16 A flat filtration membrane comprising a nonwoven porous support and a membrane layer with a first and second zone and a membrane surface for receiving feed; wherein the first zone is placed next to said membrane surface and said second zone is placed between said first zone on one side and said nonwoven porous support on the side opposite said first zone such that said nonwoven porous support is placed away from said membrane surface; and wherein in the first zone, the mean pore size increases with a mean gradient of 20 to 80 nm per 1 μm distance from said membrane surface and in the second zone, the mean pore size increases with increasing distance from said membrane surface; and wherein the first zone has a thickness of 5 to 15 μm and a mean pore size of less than or equal to 0.4 μm and the second zone has a thickness of 5 to 40 μm and a mean pore size of 0.4 to 5.0 μm; and wherein the first zone and the second zone are comprised of polysulfone and polyvinylpyrrolidone, and the filtration membrane has a clean water permeability of 200 to 3000 L/(m2·h·bar). ### Claim 17 (depends on 1) The filtration membrane as claimed in claim 1, wherein the filtration membrane is flat, the membrane surface for receiving feed is comprised within the first zone, the nonwoven is a mechanical stabilizer and said membrane comprises polyvinylpyrollidone. ### Claim 18 (depends on 1) The filtration membrane as claimed in claim 1, wherein the filtration membrane is flat, the membrane surface for receiving feed is comprised within the first zone and in the first zone the mean pore size increases with a mean gradient of 20 to 80 nm per 1 μm distance from said membrane surface and in the second zone and the mean particle size increases with a mean gradient of 200 to 800 nm per 1 μm distance from said membrane surface, the mean pore size increasing with increasing distance from said membrane surface; and said membrane comprised of a single polymer layer.