Toray Industries, Inc.

Other

Takashi Chida

Mikio Inoue

Toru Sugahara

Katsuya Sode

Kenya Okada

Takashi Ando

Masamichi Utsunomiya

Toshiya Kamae

Yasuaki Tanimura

Yasutaka Okano

Masaru Hashimoto

Michio Wakatabe

Takayuki Oda

Shinya Isoi

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 precursor fiber sheet includes short carbon fibers having an average length of 3 to 10 mm, natural pulp having an ash content of 0.15 mass % or less, and a heat-carbonizable resin, and a porous carbon sheet is obtained by carbonizing the precursor fiber sheet. This enhances gas diffusibility and water removal properties of the porous carbon sheet and has high mechanical strength and few appearance defects even when the bulk density of the porous carbon sheet is lowered.

Porous carbon sheet and precursor fiber sheet thereof

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

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.

A porous carbon sheet obtained by binding separate carbon short fibers with a carbonization product of a resin, wherein the pore mode diameter of the sheet is 45 to 90 &#x3bc;m and the mean fiber diameter of the carbon short fibers is 5 to 20 &#x3bc;m. The sheet can be produced by thermoforming a precursor fiber sheet comprising carbon short fibers of 15 to 30 g/min basis weight and a thermosetting resin of 30 to 80 g/min basis weight by hot plates having a certain clearance and carbonizing the thermosetting resin contained in thermoformed precursor fiber sheet.

Porous carbon sheet and process for production thereof

A porous carbon base material includes a sheet containing carbon short fibers dispersed randomly and a carbonized resin, in which the carbon short fibers are bound by the carbonized resin and the volume of pores having a pore diameter of 10 &#x3bc;m or less is 0.05 to 0.16 cc/g. A method for producing this porous carbon base material includes intermittently transporting a precursor fiber sheet including short carbon fibers dispersed randomly and a resin to a space between heated plates, subjecting the precursor to a heating and pressuring treatment by the heated plates while the transformation stops, carrying out the transportation of the sheet after the treatment, and then carrying out a heat treatment, to thereby carbonize the resin in the sheet.

Growing community of inventors

Otsu, Japan

Takashi Chida