# US 11,028,199 B2 · Fluoropolymer powder and method for producing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,199 B2 - Document ID: US11028199B2 - Status: Granted - Kind: B2 - Application number: 16/341,527 - Filed: 2017-10-11 - Published: 2019-12-12 - Granted: 2021-06-08 - Earliest claimed: 2016-10-14 - Assignees: Daikin Industries, Ltd. - Applicants: Daikin Industries, Ltd. - Inventors: Yuki Yotsumoto; Tadashi Ino; Kazuhiro Ohtsuka; Noriyuki Shinoki; Masaharu Nakazawa; Takashi Yoshimura; Masahiro Kondo - Web page: https://patentgrep.com/patent/US11028199B2 ## CPC - C08F 214/26: Tetrafluoroethene - C08F 2/001: {Multistage polymerisation processes characterised by a change in reactor conditions without deactivating the intermediate polymer (C08F295/00, C08F297/00 take precedence)} - C08F 2/22: Emulsion polymerisation - C08F 2/26: anionic - C08F 8/12: Hydrolysis - C08F 8/44: Preparation of metal salts or ammonium salts - C08F 214/262: {with fluorinated vinyl ethers} - C08F 216/1408: {Monomers containing halogen} - C08J 3/16: by coagulating dispersions {(C08J3/122 takes precedence)} - C08J 7/14: with acids, their salts or anhydrides - C09D 127/18: Homopolymers or copolymers of tetrafluoroethene - C08F 216/1475: {Monomers containing sulfur and oxygen} - C08F 2800/20: as weight or mass percentages - C08F 2810/00: Chemical modification of a polymer - C08F 2810/50: wherein the polymer is a copolymer and the modification is taking place only on one or more of the monomers present in minority - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) ## Abstract The invention provides a powder that is easily redispersible in a liquid medium such as water. The powder contains a fluoropolymer. The fluoropolymer contains at least one group A selected from the group consisting of —SO2Y, —COOR, —SO3X, —SO2NR12, and —COOX, wherein Y is a halogen atom; R is a C1-C4 alkyl group; X is M1/L or NR14, where M is a hydrogen atom or an L-valent metal, the L-valent metal being a metal in group 1, group 2, group 4, group 8, group 11, group 12, or group 13 of the periodic table; and R1s are each individually a hydrogen atom or a C1-C4 alkyl group. The powder exhibits a dispersion of 50% or higher. The dispersion is calculated by filtering a composition obtainable by mixing the powder with water through a mesh having an opening of 20 μm. ## Claims ### Claim 1 A powder comprising a fluoropolymer and having an aspect ratio of 3 or lower, the fluoropolymer containing at least one group A selected from the group consisting of —SO2Y, —COOR, —SO3X, —SO2NR12, and —COOX, wherein Y is a halogen atom; R is a C1-C4 alkyl group; X is M1/L or NR14, where M is a hydrogen atom or an L-valent metal, the L-valent metal being a metal in group 1, group 2, group 4, group 8, group 11, group 12, or group 13 of the periodic table; and R1s are each individually a hydrogen atom or a C1-C4 alkyl group, the powder exhibiting a dispersion of 50% or higher, the dispersion being calculated by filtering a composition obtained by mixing the powder with water through a mesh having an opening of 20 μm, wherein the powder has an average primary particle size of greater than 30 nm to 300 nm. ### Claim 2 (depends on 1) The powder according to claim 1, wherein the powder contains 0 to 20% by mass of volatile matter. ### Claim 3 (depends on 1) The powder according to claim 1, wherein the fluoropolymer contains a constitutional unit derived from a fluoromonomer represented by the following formula (I): CF2═CF—(O)n1—(CF2CFY1—O)n2—(CFY2)n3-A (I) wherein Y1 is a halogen atom or a perfluoroalkyl group; n1 is an integer of 0 or 1; n2 is an integer of 0 to 3; n2 Y1s are the same as or different from each other; Y2 is a halogen atom; n3 is an integer of 1 to 8; n3 Y2s are the same as or different from each other; and A is the same as the group A. ### Claim 4 (depends on 3) The powder according to claim 3, wherein the fluoropolymer is a copolymer of two or more monomers and contains a constitutional unit derived from a fluoromonomer represented by the formula (I) and a constitutional unit derived from a different fluorine-containing ethylenic monomer. ### Claim 5 (depends on 4) The powder according to claim 4, wherein the fluorine-containing ethylenic monomer is at least one species of monomers represented by the following formula (II): CF2═CF—Rf1 (II) wherein Rf1 is a fluorine atom, a chlorine atom, Rf2, or ORf2, where Rf2 is a C1-C9 linear or branched perfluoroalkyl group optionally containing an ether bond. ### Claim 6 (depends on 5) The powder according to claim 5, wherein any or all of the monomers represented by the formula (II) are tetrafluoroethylene. ### Claim 7 (depends on 3) The powder according to claim 3, wherein in the formula (I), Y1 is a trifluoromethyl group, Y2 is a fluorine atom, n1 is 1, n2 is 0 or 1, and n3 is 2. ### Claim 8 (depends on 1) A method for producing the powder according to claim 1, comprising: a step (1) of preparing an aqueous dispersion (a) by emulsion polymerization, the aqueous dispersion (a) containing a fluoropolymer that contains at least one group selected from the group consisting of —SO2Y and —COOR, wherein Y is a halogen atom; and R is a C1-C4 alkyl group; a step (2) of adding an alkali or an acid to the aqueous dispersion (a) to provide an aqueous dispersion (b), the aqueous dispersion (b) containing a fluoropolymer that contains at least one group selected from the group consisting of —SO3X, —SO2NR12, and —COOX, wherein X is M1/L or NR14, where M is a hydrogen atom or an L-valent metal, the L-valent metal being a metal in group 1, group 2, group 4, group 8, group 11, group 12, or group 13 of the periodic table; and les are each individually a hydrogen atom or a C1-C4 alkyl group; a step (3) of filtering the aqueous dispersion (b) and collecting a residue; and a step (4) of drying the residue at a work of 200 W or lower to provide a powder containing 0 to 20% by mass of volatile matter.