1. Field of the Invention
The preset invention relates to a rubber composition, a vulcanized rubber composition, a radiator hose, a heater hose or a radiator packing.
2. Description of the Related Art
Conventionally, an ethylene-.alpha.-olefin copolymer rubber or ethylene-.alpha.-olefin-nonconjugated diene copolymer rubber such as an ethylene-propylene rubber (EPDM) or ethylene-propylene-nonconjugated diene rubber (EPDM) is widely used for a radiator hose, a heater hose and a radiator packing. The ethylene-.alpha.-olefin copolymer rubber and ethylene-.alpha.-olefin-nonconjugated diene copolymer rubber are used as a vulcanized rubber which has been vulcanized using an organic peroxide. Then, a zinc-containing compound represented by zinc oxide is added as one essential component to a rubber composition for the purpose of preventing aging as technical commonsense. However, when a rubber composition comprising a zinc-containing compound is used for a radiator hose, a heater hose or a radiator packing, there is a problem that zinc is eluted into a cooling medium to impart disadvantage to mechanical system.