Abstract: An ion exchange membrane containing a fluorinated polymer, wherein in a case where by Raman spectroscopy, polarized light orthogonal to the thickness direction of the ion exchange membrane is irradiated to obtain a spectrum chart, whereby the ratio of the peak area a2 of Raman shift 680 to 760 cm?1 to the peak area al of Raman shift 1,025 to 1,095 cm?1 is taken as A1, and by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light parallel with the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the peak area b2 of Raman shift 920 to 1,025 cm?1 to the peak area b1 of Raman shift 1,025 to 1,095 cm?1 is taken as B1, B1/A1 is at least 1.05.

Abstract: The present invention provides a strong polymer electrolyte membrane which can provide a water electrolyzer operable at low electrolysis voltage. The polymer electrolyte membrane of the present invention comprises a fluorinated polymer and a woven fabric, wherein the weight of the woven fabric is from 20 to 95 g/m2, and the warp and weft of the woven fabric independently have a denier of from 30 to 100.

Abstract: To provide an electrolyte membrane wherein pinholes are less likely to occur even when used in a cell having an anode and a cathode under voltage for a prolonged period of time, as well as an electrolysis apparatus and a redox flow battery which contain the membrane. An electrolyte membrane comprising a fluorinated polymer containing ion-exchange groups and a woven fabric, wherein said woven fabric consists of yarns A extending in one direction and yarns B extending in a direction orthogonal to said yarns A, the aspect ratio YACA2/YACA1 exceeds 1 and is larger than the aspect ratio YAA2/YAA1, and the aspect ratio YACB2/YACB1 exceeds 1 and is larger than the aspect ratio YAB2/YAB1. (YACA2, YACA1, YAA2, YAA1, YACB2, YACB1, YAB2 and YAB1 are as defined in the specification.

Abstract: To provide a membrane electrode assembly, a solid polymer electrolyte membrane, a water electrolysis apparatus, and an electrolytic hydrogenation apparatus, that can reduce the range of increase in electrolysis voltage even when the current density increases when applied to a water electrolysis apparatus or an electrolytic hydrogenation apparatus. The membrane electrode assembly of the present invention comprises an anode having a catalyst layer, a cathode having a catalyst layer, and a solid polymer electrolyte membrane disposed between the anode and the cathode, wherein the solid polymer electrolyte membrane comprises a fluorinated polymer having ion-exchange groups and a woven fabric, wherein the aperture ratio of the woven fabric is at least 50%, and the ratio TAAVE/TBAVE calculated from the average maximum membrane thickness TAAVE and the average minimum membrane thickness TBAVE of the solid polymer electrolyte membrane is at least 1.20.

Abstract: To provide an ion exchange membrane with a catalyst layer, an ion exchange membrane and an electrolytic hydrogenation apparatus, which can lower electrolysis voltage and increase current efficiency at the time of electrolytic hydrogenation of an aromatic compound. The ion exchange membrane with a catalyst layer of the present invention has an inorganic particle layer containing inorganic particles and a binder, a layer (Sa) containing a first fluorinated polymer having sulfonic acid type functional groups, and a layer (Sb) containing a second fluorinated polymer having sulfonic acid type functional groups, and a catalyst layer, in this order, wherein the ion exchange capacity of the above first fluorinated polymer is lower than the ion exchange capacity of the above second fluorinated polymer.

Abstract: To provide an ion exchange membrane for alkali chloride electrolysis for which membrane strength is increased while membrane resistance is reduced to reduce electrolysis voltage during alkali chloride electrolysis and which prevents peeling between layers (S) and a layer (C). The ion exchange membrane for alkali chloride electrolysis comprises a layer (C) which comprises a fluorinated polymer having carboxylic acid functional groups, at least two layers (S) which comprise a fluorinated polymer having sulfonic acid functional groups, and a reinforcing material, wherein the layers (S) include a layer (Sa) and a layer (Sb), the layer (Sa) is a layer which is adjacent to the layer (C), the layer (Sb) is a layer which is not adjacent to the layer (C), the reinforcing material is disposed in the layer (Sb) substantially in parallel to the layer (Sb) in a state not in contact with the layer (Sa), and the ion exchange capacity of the layer (Sa) is lower than the ion exchange capacity of the layer (Sb).

Abstract: To provide an ion exchange membrane for alkali chloride electrolysis which has a low membrane resistance and which is capable of reducing the electrolysis voltage during the alkali chloride electrolysis, while increasing the membrane strength. An ion exchange membrane 1 for alkali chloride electrolysis wherein a reinforcing material 20 obtained by weaving with reinforcing yarns 22 and sacrificial yarns 24 is embedded in a fluoropolymer having ion exchange groups, the ion exchange membrane 1 comprises elution holes (28) formed by eluting at least a portion of a material of the sacrificial yarns 24, and in a cross section perpendicular to the length direction of the yarns, the total area (S) obtained by adding the cross-sectional area of an elution hole 28 and the cross-sectional area of a sacrificial yarn 24 remaining in the elution hole 28 is from 500 to 1,200 ?m2, and the number (n) of elution holes 28 between adjacent reinforcing yarns 22 is at least 10.

Abstract: To provide a membrane electrode assembly which is excellent in strength and is capable of reducing the electrolysis voltage when applied to a water electrolysis apparatus, and such a water electrolysis apparatus. The membrane electrode assembly of the present invention is a membrane electrode assembly for use in a water electrolysis apparatus, comprising an anode having a catalyst layer, a cathode having a catalyst layer, and a polymer electrolyte membrane disposed between the anode and the cathode, wherein the polymer electrolyte membrane comprises a fluorinated polymer having ion exchange groups, and a woven fabric, the aperture ratio of the woven fabric is at least 50%, the denier number of warp yarns and the denier number of weft yarns, constituting the woven fabric, are each independently at least 2, and a relationship of Y?240X?170 is satisfied where the membrane thickness of the polymer electrolyte membrane is Y ?m, and the ion exchange capacity of the fluorinated polymer is X meq/g dry resin.

Abstract: To provide an ion-exchange membrane that, when being used in a redox flow battery, provides excellent current efficiency and can suppress reduction in voltage efficiency. The ion-exchange membrane contains a fluorinated polymer having sulfonic acid-type functional groups and is characterized in that the difference (D?Dc) between the distance D between ion clusters measured by the small angle X-ray scattering method, and the diameter Dc of an ion cluster is larger than 0 and at most 0.50 nm.

Abstract: To provide an ion exchange membrane for alkali chloride electrolysis which is a membrane having a high water permeability and being capable of maintaining a low electrolysis voltage while suppressing the amount of water supplied to a cathode chamber to be minimum, and which is capable of forming an aqueous alkali hydroxide solution having a high caustic alkali quality. The ion exchange membrane for alkali chloride electrolysis comprises a layer 12 made of a fluorinated polymer having carboxylic acid functional groups, and a layer 14A and a layer 14B made of a fluorinated polymer having sulfonic acid functional groups, wherein a reinforcing material 20 containing reinforcing threads 22 is disposed between the layer 14A and the layer 14B, the thickness when dried, of the layer 12 is from 9 to 28 ?m, the layer 14B includes a layer having an ion exchange capacity of from 1.3 to 2.

Abstract: To provide an ion exchange membrane for alkali chloride electrolysis which has high membrane strength and low membrane resistance, thereby capable of reducing the electrolysis voltage during alkali chloride electrolysis. In this ion exchange membrane (1) for alkali chloride electrolysis, a reinforcing material 20 formed by weaving reinforcing yarns 22 and sacrificial yarns 24 is disposed in a layer (S) 14, and layer (S) 14 has elution portions 28 formed by elution of at least portions of the sacrificial yarns 24.

Abstract: To provide a process for producing an ion exchange membrane for electrolysis which has a low membrane resistance and which is capable of reducing the electrolysis voltage during the electrolysis, even if the membrane strength is increased, an ion exchange membrane for electrolysis, a precursor membrane of an ion exchange membrane for electrolysis, and an electrolysis apparatus.

Abstract: To provide an ion exchange membrane which is excellent in dimensional stability in an in-plane direction when immersed in an electrolytic solution, and a method for producing a dry ion exchange membrane. The ion exchange membrane according to the present invention is an ion exchange membrane containing a fluorinated polymer, wherein in a case where by Raman spectroscopy, polarized light orthogonal to the thickness direction of the ion exchange membrane is irradiated to obtain a spectrum chart, whereby the ratio of the peak area a2 of Raman shift 680 to 760 cm?1 to the peak area al of Raman shift 1,025 to 1,095 cm?1 is taken as A1, and by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light parallel with the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the peak area b2 of Raman shift 920 to 1,025 cm?1 to the peak area b1 of Raman shift 1,025 to 1,095 cm?1 is taken as B1, B1/A1 is at least 1.05.

Abstract: To provide an ion exchange membrane for alkali chloride electrolysis, which has low membrane resistance and which reduces the electrolysis voltage during alkali chloride electrolysis, even if the spacing between reinforcing yarns is made narrow to increase the membrane strength.

Abstract: To provide a production method whereby an ion exchange membrane for alkali chloride electrolysis can be obtained which has high current efficiency, little variation in current efficiency and high alkaline resistance. This is a method for producing an ion exchange membrane 1 having a layer (C) 12 containing a fluorinated polymer (A) having carboxylic acid type functional groups, by immersing an ion exchange membrane precursor film having a precursor layer (C?) containing a fluorinated polymer (A?) having groups convertible to carboxylic acid type functional groups, in an aqueous alkaline solution comprising an alkali metal hydroxide, a water-soluble organic solvent and water, and converting the groups convertible to carboxylic acid type functional groups to carboxylic acid functional groups, wherein the concentration of the water-soluble organic solvent is from 1 to 60 mass % in the aqueous alkaline solution (100 mass %); the temperature of the aqueous alkaline solution is at least 40° C. and less than 80° C.

Abstract: The present invention provides an ion exchange membrane can improve the current efficiency of a redox flow battery without a drop in voltage efficiency, when used in the redox flow battery. The ion exchange membrane of the present invention is an ion exchange membrane comprising a fluorinated polymer having sulfonic acid functional groups, wherein the difference (D?Dc) between the distance D between ionic clusters and the diameter Dc of ionic clusters as measured by the small angle X-ray scattering is 0.60 nm or more, and the ion exchange capacity of the fluorinated polymer is 0.95 meq/gram dry resin or more.

Abstract: The present invention provides a strong polymer electrolyte membrane which can provide a water electrolyzer operable at low electrolysis voltage. The polymer electrolyte membrane of the present invention comprises a fluorinated polymer and a woven fabric, wherein the weight of the woven fabric is from 20 to 95 g/m2, and the warp and weft of the woven fabric independently have a denier of from 30 to 100.

Abstract: To provide a method whereby it is possible to efficiently produce an ion exchange membrane for alkali chloride electrolysis, which has high current efficiency and high alkali resistance at the time of electrolyzing an alkali chloride.

Abstract: To provide an ion exchange membrane for alkali chloride electrolysis whereby it is possible to make the electrolysis voltage low and the current efficiency high at the time of performing electrolysis of an alkali chloride; a method for its production; and an alkali chloride electrolysis apparatus using it. The ion exchange membrane for alkali chloride electrolysis has a layer (C) comprising a fluorinated polymer having carbonic acid functional groups, and a layer (S) comprising a fluorinated polymer having sulfonic acid functional groups; a reinforcing material containing reinforcing threads is disposed in the layer (S); and when measured after the ion exchange membrane for alkali chloride electrolysis is immersed and held in a 32 mass % sodium hydroxide aqueous solution warmed at 90° C. for 16 hours and subsequently immersed in a 32 mass % sodium hydroxide aqueous solution at 25° C.

Abstract: To provide a method capable of efficiently producing an ion exchange membrane for alkali chloride electrolysis which has high current efficiency, little variation in current efficiency and high alkaline resistance. This is a method for producing an ion exchange membrane 1 having a layer (C) 12 containing a fluorinated polymer (A) having carboxylic acid type functional groups, by immersing an ion exchange membrane precursor film having a precursor layer (C?) containing a fluorinated polymer (A?) having groups convertible to carboxylic acid type functional groups, in an aqueous alkaline solution comprising an alkali metal hydroxide, a water-soluble organic solvent and water, wherein the proportion of structural units having carboxylic acid type functional groups in the fluorinated polymer (A) is from 13.0 to 14.50 mol %; in the layer (C) 12, the value of resistivity is from 4.0×103 to 25.0×103 ?·cm, and the variation in resistivity is at most 4.