Process for producing an electrode substrate which is uniform in physical properties

Claim 1

A process for continuously producing an electrode substrate, which process comprises the steps of: (1) kneading, at a temperature of not higher than 110° C. a raw material mixture comprising from 30 to 60% by weight of short carbon fibers, from 20 to 50% by weight of a phenol resin binder, and from 20 to 50% by weight of a molding additive of an organic high polymer having a carbonizing yield of not more than 5% by weight, said organic high polymer being selected from a copolymer resin of ethylene and vinyl acetate, and a mixture of a copolymer resin of ethylene and vinyl acetate and a polyolefin; (2) extruding the thus kneaded raw material mixture through an extrusion die; (3) thereafter heating the thus extruded raw material to a temperature of from 130° to 180° C., and press-molding the thus heated material under a pressure of from 20 to 80 kgf/cm 2 by rolling or stamping, and then (4) calcining the thus press-molded material for about one hour at a temperature of from 800° to 3000° C. in an inert atmosphere and/or under a reduced pressure, whereby said electrode substrate is formed.