Abstract: Provided herein is a resin composite material containing graphite fiber which has good electrical conductivity and changes only a little in electrical resistance after processing. These desired properties are achieved by incorporating a synthetic resin matrix with a specific type of graphite fiber. The graphite fiber has a structure characterized by that the hexagonal network planes of carbon atoms are oriented substantially parallel to the fiber axis and like the annual ring. It is produced by bringing a hydrocarbon compound into contact, at a high temperature, with a metallic catalyst in the form of ultrafine particles to yield carbon fiber grown in the gas phase, and subsequently graphitizing thus obtained carbon fiber.

Abstract: The method of producing bromine-processed graphite fibers, comprises graphitizing gas phase grown carbon fibers by bringing ultrafine particles of metal catalyst and a hydrocarbon compound suspended in a high temperature zone into contact with each other, to obtain graphite fibers having such a crystal structure that carbon hexagonal network face is substantially in parallel with the axes of fibers and is oriented coaxially, and then bringing the thus obtained graphite fibers and bromine at a temperature lower than 60.degree. C. In this case, the interplanar spacing or the lengths of the repeat distance along the c axis direction in the crystals vary with a plurality of values within a range from 10 to 40 .ANG..