RUBBER TIRE-TREAD COMPOSITION AND PASSENGER-VEHICLE PNEUMATIC TIRE USING SAME

There is provided a rubber tire-tread composition comprising (A) a rubber component comprising 45% by mass or higher of one or more isoprene-based rubbers selected from the group consisting of natural rubbers and synthetic isoprene rubbers, and (B) one or more C5/C9-based petroleum resins selected from the group consisting of aromatic-modified aliphatic petroleum resins and aliphatic-modified aromatic petroleum resins in an amount of 5 to 50 parts by mass, and (C) a fatty acid metal salt in an amount of 0.5 to 10 parts by mass of, both based on 100 parts by mass of the rubber component.