Abstract: A porous carbon sheet including at least carbon fibers, having a thickness of 30 to 95 ?m, a gas permeation resistance of 0.5 to 8.8 Pa, and a tensile strength of 5 to 50 N/cm, and a gas diffusion electrode substrate including a porous carbon sheet containing at least carbon fibers, at least one surface thereof having a microporous layer containing at least an electric conductive filler, the gas diffusion electrode substrate being dividable in the thickness direction into a smaller pore part and a larger pore part, the larger pore part having a thickness of 3 to 60 ?m.

Abstract: The present invention provides a gas diffusion electrode including a microporous layer, characterized in that the microporous layer includes at least a first microporous layer and a second microporous layer, wherein the first microporous layer contains a first hydrophobic polymer and is located on the outermost surface on one side of the microporous layer; wherein the second microporous layer contains a second hydrophobic polymer and is located on the outermost surface of the microporous layer on the side opposite to the first microporous layer, and is located on an outermost surface of the gas diffusion electrode; and wherein the first hydrophobic polymer is a resin having a melting point lower than the melting point of the second hydrophobic polymer. The present invention provides a gas diffusion electrode for a fuel cell, in which both high performance and durability are achieved.

Abstract: A gas diffusion electrode comprising microporous layers on at least one side of an electrically conductive porous substrate, wherein said gas diffusion electrode has a thickness of 30 ?m to 180 ?m, said microporous layer has thickness of 10 ?m to 100 ?m, and when said surface of the microporous layer is observed for the area 0.25 mm2 for 4000 viewing areas, the number of the viewing areas having a maximal height Rz of not less than 50 ?m is, among the 4000 viewing areas, 0 viewing areas to 5 viewing areas. A gas diffusion electrode which satisfies both the prevention of the damage to an electrolyte membrane by a gas diffusing layer and the gas diffusivity of the gas diffusing layer, and exhibits good performance as a fuel cell.

Abstract: The present invention provides a method for efficiently producing a gas diffusion electrode substrate having excellent adhesion property. This method is a method for producing a gas diffusion electrode substrate having a porous layer on at least one surface of an electroconductive porous substrate which includes the steps of a coating step wherein a coating solution containing electroconductive particles, a water-repellant material, a dispersion medium, and a surfactant is coated on the electroconductive porous substrate, a drying step wherein heating is conducted at a temperature lower than the temperature of a first heat treatment step, the first heat treatment step wherein the heating is conducted at a temperature lower than the melting point of the water-repellant material, and a second heat treatment step wherein the heating is conducted at a temperature higher than the melting point of the water-repellant material, wherein the coating solution contains at least 0.09 part by weight and up to 0.

Abstract: A gas-diffusion electrode substrate includes an electrode substrate and a microporous layer (MPL) disposed on one surface of the electrode substrate, wherein the gas-diffusion electrode substrate has a thickness of 110 ?m or more and 240 ?m or less, and where a cross section of the gas-diffusion electrode substrate is divided into a part having the MPL and a part having no MPL, and the part having no MPL is further equally divided into a part (CP1 cross section) in contact with the MPL and a part (CP2 cross section) not in contact with the MPL, the CP1 cross section has an F/C ratio of 0.03 or more and 0.10 or less and the CP2 cross section has an F/C ratio less than 0.03, wherein F is a mass of a fluorine atom, and C is a mass of a carbon atom.

Abstract: The present invention provides a gas diffusion electrode including a microporous layer, characterized in that the microporous layer includes at least a first microporous layer and a second microporous layer, wherein the first microporous layer contains a first hydrophobic polymer and is located on the outermost surface on one side of the microporous layer; wherein the second microporous layer contains a second hydrophobic polymer and is located on the outermost surface of the microporous layer on the side opposite to the first microporous layer, and is located on an outermost surface of the gas diffusion electrode; and wherein the first hydrophobic polymer is a resin having a melting point lower than the melting point of the second hydrophobic polymer. The present invention provides a gas diffusion electrode for a fuel cell, in which both high performance and durability are achieved.

Abstract: A gas diffusion electrode has a microporous layer on at least one surface of an electroconductive porous substrate. The microporous layer has a first microporous layer in contact with the electroconductive porous substrate, and a dense layer in contact with the first microporous layer. The thickness of the dense layer is at least 1 ?m. The average number density B of pores having a pore diameter of 0.15-1 ?m in the dense layer is at least 1.3A, where A is the average number density of pores having a pore diameter of 0.15-1 ?m in the microporous layer disposed on at least one surface of the electroconductive porous substrate.

Abstract: A gas diffusion electrode and a method for manufacturing the same, the gas diffusion electrode being used for a fuel cell and configured by forming a microporous layer containing conductive microparticles and water-repellent resin on at least one surface of a conductive porous base material, wherein the gas diffusibility in the thickness direction thereof is 30% or more, the conductive porous base material has a sliding angle of 70° or less and a porosity of 80% or more, and the microporous layer has a thickness of 10-50 ?m inclusive, and a porosity of 60-95% inclusive.

Abstract: A porous carbon sheet including at least carbon fibers, having a thickness of 30 to 95 ?m, a gas permeation resistance of 0.5 to 8.8 Pa, and a tensile strength of 5 to 50 N/cm, and a gas diffusion electrode substrate including a porous carbon sheet containing at least carbon fibers, at least one surface thereof having a microporous layer containing at least an electric conductive filler, the gas diffusion electrode substrate being dividable in the thickness direction into a smaller pore part and a larger pore part, the larger pore part having a thickness of 3 to 60 ?m.

Abstract: A gas diffusion electrode comprises microporous layers on at least one side of an electrically conductive porous substrate. The gas diffusion electrode has a thickness of 30 ?m to 180 ?m, and the microporous layer has a thickness of 10 ?m to 100 ?m. When the surface of the microporous layer is observed for the area 0.25 mm2 for 4000 viewing areas, the number of the viewing areas having a maximal height Rz of not less than 50 ?m is, among the 4000 viewing areas, 0 viewing areas to 5 viewing areas. A gas diffusion electrode satisfies both the prevention of the damage to an electrolyte membrane by a gas diffusing layer and the gas diffusivity of the gas diffusing layer, and exhibits good performance as a fuel cell.

Abstract: A gas diffusion electrode has a microporous layer on at least one surface of an electroconductive porous substrate. The microporous layer has a first microporous layer in contact with the electroconductive porous substrate, and a dense layer in contact with the first microporous layer. The thickness of the dense layer is at least 1 ?m. The average number density B of pores having a pore diameter of 0.15-1 ?m in the dense layer is at least 1.3 A, where A is the average number density of pores having a pore diameter of 0.15-1 ?m in the microporous layer disposed on at least one surface of the electroconductive porous substrate.

Abstract: The present invention provides a gas diffusion layer for a fuel cell that is balanced between performance and durability. The present invention provides a gas diffusion electrode having a microporous layer, wherein the microporous layer has at least a first microporous layer and a second microporous layer, the first microporous layer has a cross-sectional F/C ratio of 0.06 or more and 0.33 or less, the second microporous layer has a cross-sectional F/C ratio less than 0.06, and wherein the first microporous layer is equally divided into a part not in contact with the second microporous layer and a part in contact with the second microporous layer, in the equally divided first microporous layer.

Abstract: The present invention provides a fuel cell gas diffusion layer that satisfies both performances and durability. The present invention is a gas diffusion electrode having microporous layers on at least one side of an electrically conductive porous substrate, wherein the microporous layer has at least a first microporous layer in contact with the electrically conductive porous substrate, and a second microporous layer, wherein the second microporous layer is positioned as the outermost layer of the microporous layer, which second microporous layer contains an electrically conductive material having a linear portion.

Abstract: A gas-diffusion electrode substrate includes an electrode substrate and a microporous layer (MPL) disposed on one surface of the electrode substrate, wherein the gas-diffusion electrode substrate has a thickness of 110 ?m or more and 240 ?m or less, and where a cross section of the gas-diffusion electrode substrate is divided into a part having the MPL and a part having no MPL, and the part having no MPL is further equally divided into a part (CP1 cross section) in contact with the MPL and a part (CP2 cross section) not in contact with the MPL, the CP1 cross section has an F/C ratio of 0.03 or more and 0.10 or less and the CP2 cross section has an F/C ratio less than 0.03, wherein F is a mass of a fluorine atom, and C is a mass of a carbon atom.

Abstract: A gas diffusion electrode and a method for manufacturing the same, the gas diffusion electrode being used for a fuel cell and configured by forming a microporous layer containing conductive microparticles and water-repellent resin on at least one surface of a conductive porous base material, wherein the gas diffusibility in the thickness direction thereof is 30% or more, the conductive porous base material has a sliding angle of 70° or less and a porosity of 80% or more, and the microporous layer has a thickness of 10-50 ?m inclusive, and a porosity of 60-95% inclusive.