FLEXIBLE DUCT FOR AIR CONDITIONING SYSTEMS

摘要

The present invention relates to a composite flexible hose, preferably for use in automotive air conditioning systems, with improved thermal resistance. The hose consists of an innermost core layer, a friction rubber layer, an intermediate reinforcement layer, and an external cover layer. The innermost layer is a non-plasticized polyamide mixed with a minor portion of polyolefin corresponding to the main rubber constituent of the friction coat layer. The friction coating is formed of a rubber composite of two EPDM rubbers at a weight ratio of 50/50 and 75 parts by weight of carbon black. The intermediate fibrous reinforcement layer is formed of aramid. The external layer is an acrylate rubber comprising a blend of two ethylene acrylates at a weight ratio of 50/50 and 80 parts by weight of carbon black.