POROUS CARBON ELECTRODE MATERIAL, METHOD FOR MANUFACTURING THE SAME, AND CARBON FIBER PAPER

The present invention provides carbon fiber paper consisting of an organic high-molecular compound as a binder and carbon fibers, characterized in that the carbon fibers contain thin fibers with an average diameter smaller than 5 µm and an average fiber length of 3 to 10 mm; a porous carbon electrode substrate for a fuel cell having a thickness of 0.05 to 0.5 mm and a bulk density of 0.3 to 0.8 g/cm, also having a bending strength of 10 MPa or higher and a deflection of 1.5 mm or more at the time of bending, measured by a three-point bending test in conditions of using a sample width of 1 cm, a strain rate of 10 mm/min, and a distance between supporting points of 2 cm; and a method of producing a porous carbon electrode substrate for a fuel cell by impregnating the carbon fiber paper with a thermosetting resin, curing the thermosetting resin by heating and pressing treatment, and then carbonizing the paper. [0002] The electrode substrate of the present invention is excellent in flexibility and bending strength and able to be rolled on a roll and thus has high productivity, and the carbon fiber paper of the present invention is suitable for producing the electrode substrate.