# US 10,245,545 B2 · Embossed air filter filtration medium, filter pack, air filter unit, and method for manufacturing filtration medium for embossed air filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,245,545 B2 - Document ID: US10245545B2 - Status: Granted - Kind: B2 - Application number: 15/031,438 - Filed: 2014-10-22 - Published: 2016-08-18 - Granted: 2019-04-02 - Earliest claimed: 2013-10-23 - Assignees: Daikin Industries, Ltd. - Applicants: Daikin Industries, Ltd. - Inventors: Satoshi Hara; Kunihiko Inui; Li Bao; Makoto Kobayashi; Hitoshi Niinuma - Web page: https://patentgrep.com/patent/US10245545B2 ## CPC - B01D 46/522: {with specific folds, e.g. having different lengths} - B01D 39/1623: {of synthetic origin} - B01D 39/1692: {Other shaped material, e.g. perforated or porous sheets} - B01D 46/0001: {Making filtering elements} - B01D 46/523: {with means for maintaining spacing between the pleats or folds} - C08L 27/18: Homopolymers or copolymers or tetrafluoroethene - B01D 2239/0654: Support layers - C08L 2205/025: containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure - C08L 2205/03: containing three or more polymers in a blend - 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) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) ## Abstract An embossed air filter filtration medium has at least one porous film and a plurality of air-permeable support materials supporting the at least one porous film. The least one porous film includes a fibril-formable polytetrafluoroethylene, a non-fibril-forming and non-hot-melt-processable component, and a non-fibril-forming and hot-melt-processable component having a melting point below 320° C. Surfaces of both sides of the air filter filtration medium are formed by two air-permeable support materials of the air-permeable support materials. The air filter filtration medium has a plurality of embossed projections. The embossed air filter filtration medium may be part of a filter pack, which may be part of an air filter unit. The embossed air filter filtration medium is manufactured by laminating air-permeable support materials on the at least one porous film and embossing the air filter filtration medium to form the projections. ## Claims ### Claim 1 An embossed air filter filtration medium for trapping dust in a stream of air, the embossed air filter filtration medium comprising: an air filter filtration medium having at least one porous film including a fibril-formable polytetrafluoroethylene, a non-fibril-forming and non-hot-melt-processable component, and a non-fibril-forming and hot-melt-processable component having a melting point below 320° C., and a plurality of air-permeable support materials supporting the at least one porous film, surfaces of both sides of the air filter filtration medium being formed by two air-permeable support materials of the plurality of air-permeable support materials, and the air filter filtration medium being provided with a plurality of embossed projections. ### Claim 2 (depends on 1) The embossed air filter filtration medium according to claim 1, wherein the non-fibril-forming and hot-melt-processable component content is 0.1 wt % to less than 20 wt % of the at least one porous film. ### Claim 3 (depends on 1) The embossed air filter filtration medium according to claim 1, wherein the non-fibril-forming and hot-melt-processable component is a fluororesin. ### Claim 4 (depends on 3) The embossed air filter filtration medium according to claim 3, wherein the fluororesin is a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, or a mixture thereof. ### Claim 5 (depends on 1) The embossed air filter filtration medium according to claim 1, wherein the non-fibril-forming and non-hot-melt-processable component is a low-molecular weight polytetrafluoroethylene, a thermosetting resin, an inorganic filler, or a mixture thereof. ### Claim 6 (depends on 1) A filter pack including the embossed air filter filtration medium according to claim 1, the embossed air filter filtration medium has a folded configuration with alternate mountain folding and valley folding so as to assume a zigzag configuration. ### Claim 7 (depends on 6) The filter pack according to claim 6, wherein the plurality of embossed projections of the embossed air filter filtration medium include a plurality of pairs of mutually facing projections formed on two facing surfaces of the embossed air filter filtration medium, which have been mountain-folded or valley-folded to face one another. ### Claim 8 (depends on 7) The filter pack according to claim 7, further comprising a spacer arranged to maintain spacing between two of the projections arranged so as to face one another. ### Claim 9 (depends on 6) An air filter unit including the filter pack according to claim 6, the air filter unit further comprising a frame arranged and configured to retain the filter pack, the filter pack being sealed in the frame using a sealant. ### Claim 10 A method for manufacturing an embossed air filter filtration medium adapted to trap microparticles in a stream of air, the method comprising: providing at least one porous film including a fibril-formable polytetrafluoroethylene, a non-fibril-forming and non-hot-melt-processable component, and a non-fibril-forming and hot-melt-processable component having a melting point below 320° C.; laminating air-permeable support materials on the at least one porous film to form an air filter filtration medium with surfaces of both sides of the air filter filtration medium being formed by the air-permeable support materials; and embossing the air filter filtration medium to form a plurality of projections on the air filter filtration medium. ### Claim 11 (depends on 10) The method for manufacturing an embossed air filter filtration medium according to claim 10, wherein the embossing includes alternately mountain-folding and valley-folding the embossed air filter filtration medium to form a zigzag configuration; and while conveying the air filter filtration medium in one direction, repeatedly carrying out in order formation of a mountain fold and at least one of the plurality of projections, and formation of a valley fold and at least one other projection of the plurality of projections. ### Claim 12 (depends on 2) The embossed air filter filtration medium according to claim 2, wherein the non-fibril-forming and hot-melt-processable component is a fluororesin. ### Claim 13 (depends on 12) The embossed air filter filtration medium according to claim 12, wherein the fluororesin is a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, or a mixture thereof. ### Claim 14 (depends on 2) The embossed air filter filtration medium according to claim 2, wherein the non-fibril-forming and non-hot-melt-processable component is a low-molecular weight polytetrafluoroethylene, a thermosetting resin, an inorganic filler, or a mixture thereof. ### Claim 15 (depends on 3) The embossed air filter filtration medium according to claim 3, wherein the non-fibril-forming and non-hot-melt-processable component is a low-molecular weight polytetrafluoroethylene, a thermosetting resin, an inorganic filler, or a mixture thereof. ### Claim 16 (depends on 3) A filter pack including the embossed air filter filtration medium according to claim 3, the embossed air filter filtration medium has a folded configuration with alternate mountain folding and valley folding so as to assume a zigzag configuration. ### Claim 17 (depends on 5) A filter pack including the embossed air filter filtration medium according to claim 5, the embossed air filter filtration medium has a folded configuration with alternate mountain folding and valley folding so as to assume a zigzag configuration.