Abstract: The present invention provides an aqueous fluororesin dispersion comprising a melt-processable fluororesin which is low in fluorinated surfactant concentration and excellent in dispersion stability even when the concentration of the melt-processable fluororesin is high. The present invention is related to an aqueous fluororesin dispersion comprising a melt-processable fluororesin particle dispersed in an aqueous medium, wherein a concentration of the melt-processable fluororesin is 55 to 75% by mass relative to the aqueous fluororesin dispersion, and a fluorinated surfactant content in the aqueous fluororesin dispersion is not higher than a level corresponding to 100 ppm of the melt-processable fluororesin.

Abstract: The present invention provides a method of producing a fluoropolymer, wherein polymerization using a carboxylate ester bond-containing carboxylic acid derivative as a surfactant in an aqueous medium to give the fluoropolymer is conducted, the above carboxylate ester bond-containing carboxylic acid derivative has a carboxylate ester bond and —COOM (M representing H, NH4, Li, Na or K), the above carboxylate ester bond may optionally be substituted by fluorine atom.

Abstract: The present invention provides a method of producing a fluoropolymer aqueous dispersion by which the fluorine-containing emulsifier contained in the fluoropolymer aqueous dispersion as obtained after polymerization can be efficiently removed as well as a fluoropolymer aqueous dispersion low in fluorine-containing emulsifier concentration. The present invention is a method of producing a fluoropolymer aqueous dispersion which comprises carrying out a concentration treatment comprising a concentration operation of a pretreatment fluoropolymer aqueous dispersion, wherein the pretreatment fluoropolymer aqueous dispersion is obtained by carrying out a polymerization in an aqueous medium in the presence of a fluorine-containing surfactant (A), the fluorine-containing surfactant (A) is a fluorine-containing surfactant having an octanol/water partition coefficient of 1.5 to 3.5.

Abstract: This invention provides a novel compound which can be properly used as a surfactant, a method of producing a fluoropolymer, surfactant and a fluoropolymer aqueous dispersions using the novel compound. This invention is a fluoroalkylcarboxylic acid derivative which is represented by the general formula (i): Rf1(OCH2CF2CF2)n1OCX1X2CF2(Rf2)n2COOM??(i) wherein Rf1 represents a straight or branched fluoroalkyl group containing 1 to 20 carbon atoms, which fluoroalkyl group may optionally contain 1 to 5 oxygen atoms in the principal chain thereof, Rf2 represents a straight or branched fluoroalkylene group containing 1 to 25 carbon atoms, said fluoroalkylene group may optionally contain 1 to 5 oxygen atoms in the principal chain thereof, n1 represents an integer of 0 to 3, n2 represents an integer of 0 or 1, X1 and X2 are the same or different and each represents hydrogen atom or fluorine atom, and M represents NH4 or a monovalent metal element.

Abstract: The present invention provides a method of producing an elastomeric fluoropolymer excellent in productivity and crosslinkability. The present invention is a method of producing an elastomeric fluoropolymer comprising polymerizing a fluoromonomer in an aqueous medium in the presence of a vinyl group-containing fluorinated emulsifier and a chain transfer agent, wherein the vinyl group-containing fluorinated emulsifier is a compound having a radical polymerizable unsaturated bond and a hydrophilic group within the molecule thereof.

Abstract: The present invention provides a method of producing a fluoropolymer, wherein polymerization using a carboxylate ester bond-containing carboxylic acid derivative as a surfactant in an aqueous medium to give the fluoropolymer is conducted, the above carboxylate ester bond-containing carboxylic acid derivative has a carboxylate ester bond and —COOM (M representing H, NH4, Li, Na or K), the above carboxylate ester bond may optionally be substituted by fluorine atom.

Abstract: The invention provides a fluoroethercarboxylic acid which is represented by the general formula (I): Rf1OCHFCF2ORf2COOM ??(I) wherein Rf1 represents a partially or fully fluorinated alkyl group, which may optionally be interrupted with one or more oxygen atoms, Rf2 represents a partially or fully fluorinated alkylene group, which may optionally be interrupted with one or more oxygen atoms, and M represents a monovalent alkali metal, NH4 or H. The fluoroethercarboxylic acid can be suitably used as a surfactant and is low in bioaccumulation. The invention is also a method of fluoropolymer production and an aqueous fluoropolymer dispersion, using the fluoroethercarboxylic acid as a surfactant.

Abstract: A process for producing an aqueous fluoropolymer dispersion which includes adding a specific compound to a to-be-treated aqueous fluoropolymer dispersion containing a particle of fluoropolymer dispersed therein, the to-be-treated aqueous fluoropolymer dispersion containing a fluorinated surfactant (A) with a molecular weight lower than 1000 in an amount of 100 ppm or less of the fluoropolymer and the specific compound being (1) a sulfosuccinic acid alkyl ester or a salt thereof, or a sulfosuccinic acid fluoroalkyl ester or a salt thereof, (2) the fluorinated surfactant (A), (3) a fluorinated surfactant (B) with a molecular weight lower than 1000, differing from the fluorinated surfactant (A) and/or (4) an aliphatic carboxylic acid or a salt thereof, which compound is added in total amount of 10 to 5000 ppm of said fluoropolymer.

Abstract: The invention provides a method of producing an aqueous fluoropolymer dispersion by which aqueous fluoropolymer dispersions high in fluoropolymer concentration can be prepared in a short period of time. The present invention provides a method of producing an aqueous fluoropolymer dispersion comprising a step (1) of adding a nonionic surfactant to an aqueous fluoropolymer dispersion to be treated, a step (2) of phase-separating into a supernatant phase and an aqueous fluoropolymer dispersion phase following the step (1), and a step (3) of recovering the aqueous fluoropolymer dispersion phase by removing the supernatant phase, stirring being provided in the step (2).

Abstract: The invention provides a method of producing an aqueous fluoropolymer dispersion having a fluoropolymer concentration sufficiently high for practical purposes by using the technique of phase separation. The present invention is a method of producing an aqueous fluoropolymer dispersion comprising a step (1) of adding a nonionic surfactant having a cloud point to an aqueous fluoropolymer dispersion to be treated, a step (2), following the step (1), of phase separating into a supernatant phase and an aqueous fluoropolymer dispersion phase within a specific temperature range, and a step (3) of recovering the aqueous fluoropolymer dispersion phase by removing the supernatant phase, the specific temperature range being lower than the cloud point of the nonionic surfactant.

Abstract: The present invention provides an elastomeric fluoropolymer excellent in productivity and crosslinkability and a method of producing the same. The present invention is an elastomeric fluoropolymer having a vinyl group-containing fluorinated emulsifier-derived unit (A) and a unit (B) derived from a cure site monomer (b1) and/or bromine atom- and/or iodine atom-containing saturated aliphatic compound (b2), wherein the vinyl group-containing fluorinated emulsifier is a compound having a radical polymerizable unsaturated bond and a hydrophilic group within the molecule.

Abstract: An object of the present invention is to provide an aqueous fluoropolymer dispersion inhibited from viscosity rising and excellent in mechanical stability in spite of a low fluorinated surfactant concentration. The invention provides an aqueous fluoropolymer dispersion comprising particles of a fluoropolymer as dispersed in an aqueous medium wherein a fluorinated surfactant (A) having a molecular weight lower than 1000 amounts to not higher than 100 ppm of the mass of the fluoropolymer, the aqueous fluoropolymer dispersion containing an anionic surfactant (B) other than the fluorinated surfactant (A) as well as a water-soluble polymer (C).

Abstract: Disclosed is a method for producing a fluorine-containing elastomer polymer which is excellent in productivity and crosslinkability. Specifically disclosed is a method for producing a fluorine-containing elastomer polymer wherein a fluorine-containing monomer is polymerized in an aqueous solvent in the presence of an emulsifying agent containing a fluorine-containing vinyl group and a chain transfer agent. This method for producing a fluorine-containing elastomer polymer is characterized in that the emulsifying agent containing a fluorine-containing vinyl group is composed of a compound having a radically polymerizable unsaturated bond and a hydrophilic group in a molecule.

Abstract: The present invention provides a method of producing a fluororesin aqueous dispersion which can produce a fluororesin aqueous dispersion low in fluorine-containing surfactant concentration and high in polytetrafluoroethylene concentration with high efficiency. The invention provides a method of producing a fluororesin aqueous dispersion which comprises subjecting a crude fluororesin aqueous dispersion comprising a polytetrafluoroethylene particle dispersed in an aqueous medium to treatment with an ion-exchange resin and to treatment for concentration by phase separation in the presence of an electrolyte and/or a fluorine-free anionic surfactant.

Abstract: The present invention provides a method of producing an elastomeric fluoropolymer excellent in moldability and processability and in mechanical strength, such as permanent compression set, and chemical strength, such as chemical resistance. The present invention is a method of producing an elastomeric fluoropolymer which comprises first polymerization step for obtaining an aqueous emulsion by emulsion polymerization of a fluoromonomer [A] in an aqueous medium in the presence of a vinyl group-containing fluorinated emulsifier and second polymerization step for producing an elastomeric fluoropolymer by emulsion polymerization of a fluoromonomer [B] in the aqueous emulsion, wherein the vinyl group-containing fluorinated emulsifier is a compound having a radical polymerizable unsaturated bond and a hydrophilic group within the molecule thereof.

Abstract: There is provided a thermosetting powder coating composition comprising (A1) a fluorine-containing copolymer and (B) a curing agent, in which the copolymer contains, as essential structural units, a fluoroolefin unit, an alkene unit and cyclohexyl vinyl ether unit and/or p-tertiary butyl vinyl benzoate unit, has a sum of cyclohexyl vinyl ether unit and p-tertiary butyl vinyl benzoate unit of from 5 to 45% by mole, has a thermal transition temperature of from 45° to 120° C. and has a crosslinkable reaction group. The thermosetting powder coating composition is excellent in storage stability and provides a coating film possessing a smooth surface and enhanced impact resistance.

Abstract: The object of the present invention is a fluoropolymer aqueous dispersion showing only a moderate viscosity increase upon temperature rise and having a low fluorine-containing anionic surfactant concentration as well as a method of producing such fluoropolymer aqueous dispersion. The present invention provides a fluoropolymer aqueous dispersion comprising a particle comprising a fluoropolymer dispersed in an aqueous medium in the presence of a nonionic surfactant, wherein a supernatant for assaying as obtained by subjecting the fluoropolymer aqueous dispersion to 30 minutes of centrifugation at 25° C. and at a gravitational acceleration of 1677 G, when subjected to high-performance liquid chromatography [HPLC] under the conditions of a flow rate of 1.0 ml/minute and a column temperature of 40° C. using an acetonitrile/0.

Abstract: The present invention provides a surfactant making it possible to obtain particles comprising a fluoropolymer at a size smaller in diameter in an aqueous dispersion obtained by polymerization in the presence of the same. The present invention is a surfactant comprising a fluorine-containing-sulfobutanedioic-acid-ester derivative represented by the general formula (i): Y—Rf1—(CH2)m—OCOCH(SO3M)-CH2COO—(CH2)n—Rf2—Y??(i) wherein Y represents hydrogen atom or fluorine atom; when Y is hydrogen atom, one of Rf1 and Rf2 is —(CF2CF2)3— and the other is —(CF2CF2)2— or —(CF2CF2)3— and, when Y is fluorine atom, Rf1 and Rf2 are the same or different and each is a divalent hydrocarbon group containing 1 to 4 carbon atoms and containing at least one fluorine atom; m and n are the same or different and each represents an integer of 1 to 3; and M represents NH4, Li, Na, K or H.

Abstract: The present invention provides a method of producing a fluoropolymer aqueous dispersion by which the fluorine-containing emulsifier contained in the fluoropolymer aqueous dispersion as obtained after polymerization can be efficiently removed as well as a fluoropolymer aqueous dispersion low in fluorine-containing emulsifier concentration. The present invention is a method of producing a fluoropolymer aqueous dispersion which comprises carrying out a concentration treatment comprising a concentration operation of a pretreatment fluoropolymer aqueous dispersion, wherein the pretreatment fluoropolymer aqueous dispersion is obtained by carrying out a polymerization in an aqueous medium in the presence of a fluorine-containing surfactant (A), the fluorine-containing surfactant (A) is a fluorine-containing surfactant having an octanol/water partition coefficient of 1.5 to 3.5.

Abstract: The present invention provides a tetrafluoroethylene polymer aqueous dispersion obtained by carrying out a TFE polymerization in an aqueous medium in the presence of a fluorovinyl group-containing emulsifier, wherein the TFE polymer aqueous dispersion contains a particle comprising a TFE polymer dispersed in the aqueous medium, the fluorovinyl group-containing emulsifier comprises a fluorovinyl group-containing compound, and the TFE polymer aqueous dispersion has a fluorine-containing surfactant content of not higher than 1000 ppm by mass.