FOAM INSULATING ELECTRIC WIRE AND ITS MANUFACTURE

摘要

PURPOSE:To prevent water from infiltrating a foam insulating layer and prevent the degrade of electric properties of an electric wire due to the moisture even when the wire is used in highly humid environments by impregnating water repelling resin in the foam insulating layer. CONSTITUTION:A foam resin in which a core forming agent and nitrogen gas are mixed is extruded on the outer circumference of a conductor 1 of a silver- coated soft copper wire and a foam insulating layer 2 at a prescribed foaming degree is formed to give a foam electric wire. Then the foam electric wire is led to pass a water-repelling resin layer filled with silicone oil at about 200 deg.C temperature to impregnate the foam insulating layer 2 with the silicone oil. The silicone oil infiltrate the foam insulating layer 2 to form a water-repelling resin layer 3.