Abstract: To provide a method for producing a perfluorinated compound, capable of easily producing a perfluorinated compound from which a high molecular weight polymer can be produced by a polymerization reaction, and a method for producing a fluorinated polymer using it.

Abstract: A circuit board unit includes a first circuit board having a first ground layer, a second circuit board having a second ground layer and arranged so as to be opposed to the first circuit board, a connector unit having a first connector attached to the first circuit board, and a second connector attached to the second circuit board and coupled to the first connector, and a metal member arranged between the first circuit board and the second circuit board, and configured to electrically couple the first ground layer and the second ground layer to each other. The metal member is arranged so as to be adjacent to the connector unit.

Abstract: To provide a liquid composition capable of forming a membrane excellent in durability against hydrogen peroxide or peroxide radicals and excellent in hydrogen gas barrier property; a polymer electrolyte membrane; a membrane electrode assembly; and a polymer electrolyte fuel cell. Liquid composition comprising a liquid medium, an acid-type sulfonic acid group-containing fluorocarbon polymer of which the hydrogen gas permeation coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10% is at most 2.5×10?9 cm3·cm/(s·cm2·cmHg), and cerium atoms; a polymer electrolyte membrane 15 comprising the acid-type sulfonic acid group-containing fluorocarbon polymer, and cerium atoms; and a membrane electrode assembly 10 comprising an anode 13 having a catalyst layer, a cathode 14 having a catalyst layer, and the polymer electrolyte membrane 15 disposed between the anode 13 and the cathode 14.

Abstract: An acid-type sulfonic acid group-containing polymer containing perfluoromonomer units, no monomer units having a halogen atom other than a fluorine atom, and acid type sulfonic acid groups, whose hydrogen gas permeability coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10% is at most 2.5×10?9 cm3·cm/(s·cm2·cmHg), and whose mass reduction rate when immersed in hot water at 120° C. for 24 hours is at most 15 mass %. Liquid composition, membrane electrode assembly, polymer electrolyte fuel cell, and ion exchange membrane utilizing the acid-type sulfonic acid group-containing polymer.

Abstract: To provide a perfluoropolymer capable of producing an electrolyte membrane excellent in mechanical strength in high temperature environments; as well as a liquid composition, polymer electrolyte membrane, membrane electrode assembly and polymer electrolyte water electrolyzer, obtainable by using the perfluoropolymer. The perfluoropolymer of the present invention contains perfluoromonomer units, does not substantially contain units having a halogen atom other than a fluorine atom, does not substantially contain units having a ring structure, and has acid-type sulfonic acid groups, wherein the perfluoromonomer units contain at least one type of units A selected from the group consisting of perfluorovinyl ether units and perfluoroallyl ether units; the ion exchange capacity is from 0.9 to 1.4 milliequivalent/gram dry resin; and the storage modulus at 120° C. is at least 100 MPa.

Abstract: To provide an electrolyte material which has a high proton conductivity and which is excellent in hot water resistance. An electrolyte material which is formed of a polymer H having units represented by the formula u1 and units based on tetrafluoroethylene, wherein the polymer H has an equivalent weight EW of from 400 to 550 g/eq, and the mass reduction ratio when immersed in hot water at 120° C. for 24 hours is at most 15 mass %: wherein Q11 is a perfluoroalkylene group which may have an etheric oxygen atom, Q12 is a single bond or a perfluoroalkylene group which may have an etheric oxygen atom, Y1 is a fluorine atom or the like, s is 0 or 1, Rf1 is a perfluoroalkyl group which may have an etheric oxygen atom, X1 is an oxygen atom or the like, a is 0 when X1 is an oxygen atom, and Z+ is H+ or the like.

Abstract: A fluorosulfonyl group-containing polymer having units represented by the following formula u1, a sulfonic acid group-containing polymer having fluorosulfonyl groups in the fluorosulfonyl group-containing polymer converted into sulfonic acid groups, its production method and its applications: wherein RF1 and RF2 are a C1-3 perfluoroalkylene group.

Abstract: The present invention provides a fluoropolymer containing fluorosulfonyl groups capable of forming a polymer electrolyte membrane with high conductivity and hot water resistance, a method for its production, a fluoropolymer containing acid-form sulfonic acid groups and a method for its production, a polymer electrolyte membrane, a membrane-electrode assembly and a polymer electrolyte fuel cell. The method for producing a fluoropolymer containing fluorosulfonyl groups of the present invention comprises copolymerizing a monomer m1 (CF2?CFCF2O-Q1-SO2F) and TFE in a reactor at a temperature of from 150 to 200° C. in the presence of a radical polymerization initiator, wherein the radical polymerization initiator is continuously or sequentially added into the reactor so that the concentration of the radical polymerization initiator is kept to at most 2.

Abstract: A mounting member mounts an imaging apparatus on a projection optical apparatus that projects image light. The mounting member includes a first plate part to which the imaging apparatus is fixed, the first plate part having a shape of a planar plate, and a second plate part having a shape of a planar plate and extending from the first plate part, the second plate part being fixed to the projection optical apparatus. The first plate part has a first surface and a second surface opposite from the first surface. The second plate part is disposed on the side facing the second surface. The first surface is a placement surface where the imaging apparatus is placed.

Abstract: A method for producing a fluorosulfonyl group-containing compound to obtain a compound represented by the following formula 5 from a compound represented by the following formula 1 as a starting material and a method for producing a fluorosulfonyl group-containing monomer in which the fluorosulfonyl group-containing compound is used: wherein R1 and R2 are a C1-3 alkylene group, and RF1 and RF2 are a C1-3 perfluoroalkylene group.

Abstract: A method for producing a fluorosulfonyl group-containing compound to obtain a compound represented by the following formula 5 from a compound represented by the following formula 1 as a starting material and a method for producing a fluorosulfonyl group-containing monomer in which the fluorosulfonyl group-containing compound is used: wherein R1 and R2 are a C1-3 alkylene group, and RF1 and RF2 are a C1-3 perfluoroalkylene group.

Abstract: To provide a polymer electrolyte membrane capable of producing a polymer electrolyte fuel cell excellent in power generation characteristics and excellent in hydrogen gas utilization efficiency, as well as a membrane electrode assembly and a polymer electrolyte fuel cell obtainable by using it. The polymer electrolyte membrane of the present invention comprises a polymer electrolyte, of which the hydrogen gas permeation coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10% is at most 2.4×10?9 cm3·cm/(s·cm2·cmHg) and has a membrane thickness of from 7 to 20 ?m.

Abstract: To provide a polymer electrolyte membrane which can be applied to a polymer electrolyte water electrolyzer, and is capable of producing a polymer electrolyte water electrolyzer having a low electrolytic voltage and excellent in hydrogen gas recovery efficiency, as well as a membrane electrode assembly and a polymer electrolyte water electrolyzer obtainable by using it. The polymer electrolyte membrane of the present invention contains a polymer electrolyte, of which the hydrogen gas permeation coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10%, is at most 2.4 x 10?9 cm3.cm/(s.cm2.cmHg), wherein the membrane resistance value under the conditions of a temperature of 80° C. and a relative humidity of 50%, is from 50 to 150 mn.cm2.

Abstract: To provide a sulfonic acid group-containing polymer which is capable of forming a low hydrogen permeable membrane, which shows a high ion exchange capacity, and which shows a proper softening temperature. The sulfonic acid group-containing polymer has units u1 represented by the following formula u1, units u2 represented by the following formula u2, and units u3 based on tetrafluoroethylene, in the formula u1, RF1 and RF2 are each independently a C1-3 perfluoroalkylene group, and Z+ is a hydrogen ion, a metal ion, or an ammonium ion, —[CF2—CF(CF2O—Rf1)]—??Formula u2 in the formula u2, Rf1 is a perfluoroalkyl group which may contain a SO3?Z+ group and/or an etheric oxygen atom.

Abstract: To provide a polymer wherein a linking group that connects the main chain of the polymer and a cyclic perfluoroaliphatic disulfonimide skeleton, is a fluoroalkylene group which may have an ether oxygen atom. A polymer which has either one or both of units represented by formula u1-1 and units represented by formula u1-2: RF1, RF2: a C1-3 perfluoroalkylene group; RF3: a C1-6 perfluoroalkylene group; m: 0 or 1; and X: a hydrogen atom, an alkali metal atom, a fluorine atom, an alkyl group, ammonium or the like.

Abstract: To provide a perfluoropolymer capable of producing an electrolyte membrane excellent in electrical conductivity and mechanical strength under high temperature environment, as well as a liquid composition, a polymer electrolyte membrane, a membrane electrode assembly and a polymer electrolyte fuel cell, obtainable by using the perfluoropolymer. The perfluoropolymer of the present invention contains perfluoromonomer units, does not substantially contain units having a halogen atom other than a fluorine atom, does not substantially contain units having a ring structure, and has acid-type sulfonic acid groups, wherein the perfluoromonomer units contain at least one type of units A selected from the group consisting of perfluoro vinyl ether units and perfluoro allyl ether units; the ion exchange capacity is from 1.4 to 2.5 milliequivalent/gram dry resin; and the storage modulus at 120° C. is at least 60 MPa.

Abstract: To provide an acid-type sulfonic acid group-containing polymer which is excellent in hydrogen gas barrier properties and hot water resistance and which generates less oligomer during production; a liquid composition and a polymer electrolyte membrane comprising this acid-type sulfonic acid group-containing polymer; and a membrane electrode assembly and a polymer electrolyte fuel cell provided with the polymer electrolyte membrane. This acid-type sulfonic acid group-containing polymer is a polymer which has perfluoromonomer units, no monomer units having a halogen atom other than a fluorine atom, and acid-type sulfonic acid groups, and of which the hydrogen gas permeability coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10%, is at most 2.5×10?9 cm3·cm/(s·cm2·cmHg), and the mass reduction rate when being immersed in hot water at 120° C.

Abstract: To provide a method for producing a polymer, whereby it is possible to obtain a sulfonic acid group-containing polymer having a high TQ value and a high ion exchange capacity. A method for producing a fluorosulfonyl group-containing fluorinated polymer, which comprises polymerizing a monomer represented by the following formula ml and tetrafluoroethylene, at a temperature of at least 110° C. and at most 250° C.: in the above formula, RF1 and RF2 are each a C1-3 perfluoroalkylene group.

Abstract: To provide a liquid composition capable of forming a membrane excellent in durability against hydrogen peroxide or peroxide radicals and excellent in hydrogen gas barrier property; a polymer electrolyte membrane; a membrane electrode assembly; and a polymer electrolyte fuel cell. Liquid composition comprising a liquid medium, an acid-type sulfonic acid group-containing fluorocarbon polymer of which the hydrogen gas permeation coefficient under the conditions of a temperature of 80° C. and a relative humidity of 10% is at most 2.5×10?9 cm3·cm/(s·cm2·cmHg), and cerium atoms; a polymer electrolyte membrane 15 comprising the acid-type sulfonic acid group-containing fluorocarbon polymer, and cerium atoms; and a membrane electrode assembly 10 comprising an anode 13 having a catalyst layer, a cathode 14 having a catalyst layer, and the polymer electrolyte membrane 15 disposed between the anode 13 and the cathode 14.

Abstract: To provide a perfluoropolymer capable of producing an electrolyte membrane excellent in mechanical strength in high temperature environments; as well as a liquid composition, polymer electrolyte membrane, membrane electrode assembly and polymer electrolyte water electrolyzer, obtainable by using the perfluoropolymer. The perfluoropolymer of the present invention contains perfluoromonomer units, does not substantially contain units having a halogen atom other than a fluorine atom, does not substantially contain units having a ring structure, and has acid-type sulfonic acid groups, wherein the perfluoromonomer units contain at least one type of units A selected from the group consisting of perfluorovinyl ether units and perfluoroallyl ether units; the ion exchange capacity is from 0.9 to 1.4 milliequivalent/gram dry resin; and the storage modulus at 120° C. is at least 100 MPa.