▎ 摘　　要

NOVELTY - A graphene oxide sheet is obtained by dispersing a graphene-containing carbon substance using a dispersing agent to reduce the size of the aggregation unit of graphene-containing carbon substance, and oxidizing the resulting product. The graphene oxide sheet is capable of reducing to produce substance having graphene structure. USE - Graphene oxide sheet is used for manufacturing graphene-containing material used for manufacturing friction material, conductive fiber, electroconductive material, carbon fiber, and high-strength weight-reduction metal material (all claimed). ADVANTAGE - The graphene oxide sheet has excellent electroconductivity and quality. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) graphene-containing material; (2) friction material, which contains graphene-containing material; (3) conductive fiber, which is obtained by reducing the graphene oxide sheet in a fiber; (4) electroconductive material, which is obtained by covering surface of polymer particles using graphene oxide sheet and reducing aggregate of the polymer particles; (5) carbon fiber, which is obtained by flameproofing and carbonizing mixture containing graphene oxide sheet and polyacrylonitrile; (6) high-strength weight-reduction metal material, which is obtained by mixing and drying graphene oxide sheet aqueous solution, and performing heating and pressurization with melting sintering ; (7) manufacture of the graphene oxide sheet; (8) manufacture of the graphene-containing material; (9) manufacture of the friction material; (10) manufacture of the conductive fiber; (11) manufacture of the electroconductive material; (12) manufacture of the carbon fiber; and (13) manufacture of the high strength weight reduction metal material.