# US 2019/0314749 A1 · Filter medium and method for producing such a filter medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0314749 A1 - Document ID: US20190314749A1 - Status: Published application - Kind: A1 - Application number: 16/314,596 - Filed: 2017-06-27 - Published: 2019-10-17 - Earliest claimed: 2016-07-01 - Assignees: Mahle International GmbH - Applicants: Mahle International GmbH - Inventors: Eva Boendel; Hein Martin - Web page: https://patentgrep.com/patent/US20190314749A1 ## CPC - B01D 46/0028: {provided with antibacterial or antifungal means} - B01J 41/04: Processes using organic exchangers - B01D 39/1623: {of synthetic origin} - B01D 2239/0442: Antimicrobial, antibacterial, antifungal additives - B01D 2239/10: Filtering material manufacturing - B60H 3/0658: {Filter elements specially adapted for their arrangement in vehicles (B60H3/0608 takes precedence)} - 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) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - B60H: ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES ## Abstract A coating solution for producing a biofunctional surface coating and/or depth coating of a filter medium may include a solvent, an anti-pathogenic substance, an ion exchanger, and a polymeric cross-linking agent. The ion exchanger may be hygroscopic and may include functional cation exchanger groups with sulphonic acid groups. ## Claims ### Claim at position 1 -22. (canceled) ### Claim 23 A coating solution for producing a biofunctional surface coating and/or depth coating of a filter medium, comprising a solvent, an anti-pathogenic substance, an ion exchanger, and a polymeric cross-linking agent, wherein the ion exchanger is hygroscopic and includes functional cation exchanger groups with sulphonic acid groups. ### Claim 24 (depends on 23) The coating solution according to claim 23, wherein the solvent includes at least one of water, alcohol, diols, polyols, ethanol, i-propanol, propylene glycol, ethylene glycol, glycerine, ethylene glycol monoethyl ether, and ethylene glycol monobutyl ether. ### Claim 25 (depends on 23) The coating solution according to claim 23, wherein the solvent includes at least one of cationic tensides, anionic tensides, non-ionic tensides, and amphoteric tensides. ### Claim 26 (depends on 23) The coating solution according to claim 23, wherein the solvent is composed of water at more than 50% by weight. ### Claim 27 (depends on 23) The coating solution according to claim 23, wherein a concentration of the ion exchanger in the coating solution is 1% by weight to 25% by weight. ### Claim 28 (depends on 23) The coating solution according to claim 23, wherein a concentration of the polymeric cross-linking agent in the coating solution is 0.1% by weight to 30% by weight. ### Claim 29 (depends on 23) The coating solution according to claim 23, wherein the solvent includes anionic tensides. ### Claim 30 (depends on 23) The coating solution according to claim 23, wherein a concentration of the polymeric cross-linking agent in the coating solution is 0.3% by weight to 10% by weight. ### Claim 31 A method for producing a filter medium having a filter material, comprising: bringing the filter material into contact with an anti-pathogenic substance, an ion exchanger, and a polymeric cross-linking agent via a coating solution including a solvent, the anti-pathogenic substance, the ion exchanger, and the polymeric cross-linking agent; securely arranging the anti-pathogenic substance, the ion exchanger, and the polymeric cross-linking agent at least one of on the filter material and in the filter material via vaporizing the solvent; fixing the anti-pathogenic substance and the ion exchanger on the filter material via activating the polymeric cross-linking agent with the ion exchanger, wherein the polymeric cross-linking agent and the ion exchanger are coordinated with one another such that the ion exchanger activates the polymeric cross-linking agent; and wherein the ion exchanger is hygroscopic and includes functional cation exchanger groups with sulphonic acid groups. ### Claim 32 (depends on 31) The method according to claim 31, wherein the polymeric cross-linking agent, in a non-cross-linked state, is a water-soluble cross-linking agent which is convertable to a water-insoluble cross-linking agent when activated. ### Claim 33 (depends on 32) The method according to claim 32, wherein activating the polymeric cross-linking agent includes activating the water-soluble cross-linking agent via acid-catalysed dehydration. ### Claim 34 A filter medium for filtering air in a passenger compartment of a motor vehicle, comprising a filter material and produced via a process including: bringing the filter material into contact with an anti-pathogenic substance, an ion exchanger, and a polymeric cross-linking agent via a coating solution including a solvent, the anti-pathogenic substance, the ion exchanger, and the polymeric cross-linking agent; securely arranging the anti-pathogenic substance, the ion exchanger, and the polymeric cross-linking agent at least one of on the filter material and in the filter material via vaporizing the solvent; and fixing the anti-pathogenic substance and the ion exchanger on the filter material via activating the polymeric cross-linking agent with the ion exchanger; wherein the polymeric cross-linking agent and the ion exchanger are coordinated with one another such that the ion exchanger activates the polymeric cross-linking agent; and wherein the ion exchanger is hygroscopic and includes functional cation exchanger groups with sulphonic acid groups. ### Claim 35 (depends on 34) The filter medium according to claim 34, wherein the anti-pathogenic substance and the ion exchanger are included in at least one of a single coating, a single ply, and a single layer of the filter material. ### Claim 36 (depends on 34) The filter medium according to claim 34, wherein the ion exchanger at least one of is formed from and includes a water-soluble sulphonated aliphatic and an aromatic organic compound with an ion exchanger capacity. ### Claim 37 (depends on 34) The filter medium according to claim 34, wherein the anti-pathogenic substance is configured in an antibacterial and antiallergenic manner. ### Claim 38 (depends on 34) The filter medium according to claim 34, wherein the anti-pathogenic substance is composed of at least one of a plurality of antioxidative materials, a plurality of enzymes, and a plurality of suitable ligands. ### Claim 39 (depends on 35) The filter medium according to claim 35, wherein the anti-pathogenic substance at least one of includes and is composed of a plurality of polyphenols. ### Claim 40 (depends on 34) The filter medium according to claim 34, wherein the polymeric cross-linking agent is configured as at least one of a retarding matrix and a matrix material such that the anti-pathogenic substance connected therein and the ion exchanger are released over a predetermined period of time. ### Claim 41 (depends on 34) The filter medium according to claim 34, wherein the filter medium is included in a plurality of filter plies of a filter element. ### Claim 42 A filter element of a passenger compartment air filter of an air-conditioning system of a vehicle, comprising a filter medium including a filter material, the filter material produced via a process including: bringing the filter material into contact with an anti-pathogenic substance, an ion exchanger, and a polymeric cross-linking agent via a coating solution including a solvent, the anti-pathogenic substance, the ion exchanger, and the polymeric cross-linking agent; securely arranging the anti-pathogenic substance, the ion exchanger, and the polymeric cross-linking agent at least one of on the filter material and in the filter material via vaporizing the solvent; and fixing the anti-pathogenic substance and the ion exchanger on the filter material via activating the polymeric cross-linking agent with the ion exchanger; wherein the polymeric cross-linking agent and the ion exchanger are coordinated with one another such that the ion exchanger activates the polymeric cross-linking agent; and wherein the ion exchanger is hygroscopic and includes functional cation exchanger groups with sulphonic acid groups.