Toray Industries, Inc.

Tdk Corporation

Toru Sugahara

Katsuya Sode

Takashi Chida

Takashi Ando

Masamichi Utsunomiya

Takashi Tanoue

Hiroshi Kurihara

Toshiya Kamae

Yasuaki Tanimura

Masaru Hashimoto

Kazuya Matsumura

Michio Wakatabe

Miki Kasabo

Toshifumi Saito

Yuya Umezaki

Tetsuya Sunahara

A porous carbon sheet including at least carbon fibers, having a thickness of 30 to 95 &#x3bc;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 &#x3bc;m.

Carbon sheet, gas diffusion electrode substrate, and fuel cell

A porous carbon sheet includes a carbon fiber and a binding material, wherein when in a measured surface depth distribution, a ratio of an area of a portion having a depth of 20 &#x3bc;m or less in a measured area of one surface is a surface layer area ratio X, and a ratio of an area of a portion having a depth of 20 &#x3bc;m or less in a measured area of another surface is a surface layer area ratio Y, the surface layer area ratio X is larger than the surface layer area ratio Y, and a difference between the surface layer area ratios is 3% or more and 12% or less.

Carbon sheet, gas diffusion electrode substrate and fuel cell

The purpose of the present invention is to provide a carbon sheet that is suitably employed in a gas-diffusion-electrode substrate that has excellent flooding resistance and with which it is possible to suppress internal peeling of the carbon sheet. In order to achieve the aforementioned purpose, the present invention has the following configuration. Specifically, provided is a porous carbon sheet containing carbon fibers and a binder, wherein, in a section between a surface on one side of the carbon sheet and a surface on the other side thereof, when layers obtained by dividing, under compression, the carbon sheet into six equal parts in the thickness direction are assumed to be layer, layer, layer, layer, layer, and layer, in order starting from the layer including the surface on the one side to the layer including the surface on the other side, the layer in which the packing ratio under compression is the greatest is layer, and the relationships of the packing ratios under compression among layer, layer, layer, layer, and layerare such that layerhas the greatest packing ratio, and layerhas the second-greatest packing ratio.

Carbon sheet, gas diffusion electrode substrate, wound body, and fuel cell

A porous carbon sheet contains carbon fiber and a binder, wherein the carbon sheet is characterized in that in a section from a plane having a 50% filling ratio closest to one surface to a plane having a 50% filling ratio closest to the other surface, when letting layer X be a layer with the largest filling ratio close to the one surface, layer Y be a layer with a filling ratio smaller than layer X close to the other surface, and layer Z be the layer positioned between layer X and layer Y for layers obtained by dividing the carbon sheet equally into three in a direction perpendicular to the surfaces, the filling ratio for the layers becomes smaller in order of layer X, layer Y, and layer Z.

Flame-resistant paper for radio wave absorber members includes 40 to 70% by mass of pulp; 5 to 50% by mass of aluminum hydroxide powder; and 3 to 15% by mass of a flame retardant consisting of a polyborate, wherein the flame retardant consisting of a polyborate is contained in an amount of 7 to 25% by mass relative to the amount of the pulp.

Flame-resistant paper for wave absorber member and wave absorber member

An electromagnetic wave absorber has a configuration in which at least three hollow tetrahedrons, each having one open face, are connected to one another so that each surface opposite to a respective open face of the hollow tetrahedrons defines a respective side face of a hollow pyramid. Preferably, the electromagnetic wave absorber is made of sheet electromagnetic wave absorption members, which have a corrugated board structure in which at least one sheet includes an electrically conductive material. The electromagnetic wave absorber is low-cost, has reduced transport volume, excellent electromagnetic wave absorption characteristics from low frequency to high frequency with a shorter absorber length, has no or small difference in characteristics due to polarization plane, is lightweight and high in structural strength, and easy to manufacture and install.

Growing community of inventors

Otsu, Japan

Toru Sugahara