Abstract: There is provided a novel meta-type wholly aromatic polyamide fiber which has a high breaking strength and can inhibit coloration or discoloration under high temperatures, while retaining latent properties of the meta-type wholly aromatic polyamide fiber, such as heat resistance and flame retardancy. Components or conditions of a coagulation bath are appropriately controlled so as to give a dense coagulation state having no skin-core structure, plastic stretching is performed within a specific ratio, and further, subsequent heat stretching conditions are made proper, thereby obtaining a meta-type wholly aromatic polyamide fiber containing substantially no layered clay mineral, in which the amount of solvent remaining in the fiber is 1.0% by mass or less based on the whole fiber, and the breaking strength of the fiber is from 4.5 to 6.0 cN/dtex.

Abstract: A carbon fiber paper including carbon fibers having a surface area ratio of 1.05 or more, and a porous carbon electrode substrate for a fuel cell having this carbon fiber paper as a constituent. The electrode substrate for a fuel cell has carbon fibers uniformly dispersed therein and is flexible. The carbon fiber paper is suitable for production of the electrode substrate.

Abstract: A carbon fiber paper including carbon fibers having a surface area ratio of 1.05 or more, and a porous carbon electrode substrate for a fuel cell having this carbon fiber paper as a constituent. The electrode substrate for a fuel cell has carbon fibers uniformly dispersed therein and is flexible. The carbon fiber paper is suitable for production of the electrode substrate.

Abstract: An electric double layer capacitor containing a polymer gel electrolyte layer provided between polarizable electrodes, wherein the polymer gel electrolyte layer contains a nonaqueous electrolytic solution, and a fibrous sheet material containing mainly a fiber or pulp material capable of forming a polymer gel with the nonaqueous electrolytic solution.