| abstract |
A process for producing a rubber composition containing a nonconjugated polyene copolymer (A), a softener (B) and a diene rubber (C), comprising: a step of mixing a copolymer composition (I), said copolymer composition (I) comprising 100 parts by weight of a nonconjugated polyene copolymer (A), said nonconjugated polyene copolymer (A) being a random copolymer containing 96 to 70 mol % of the structural units derived from α-olefin (A1) and 4 to 30 mol % of the structural units derived from nonconjugated polyene (A2) and having a glass transition temperature (Tg) of −25 to 20° C., and 1 to 100 parts by weight of the softener (B); the diene rubber (C); and optionally further the softener (B). A tire tread using the rubber composition and a tire having the tire tread. |