Abstract: The present invention relates to an insulated wire comprising a conductor and at least two insulating layers provided on the outer periphery of the conductor. The inner insulating layer is provided directly or via another insulation on the outer periphery of the conductor and comprises a polyolefin compound containing 20 to 80 parts by weight of at least one substance selected from ethylene .alpha.-olefin copolymer, ethylene .alpha.-olefin polyene copolymer (.alpha.-olefin having the carbon numbers of C.sub.3 -C.sub.10, polyene being non-conjugated diene).

Abstract: The present invention relates to a cable used to supply electric power to a pump for pumping crude oil from an oil well. It is consisted of an insulating layer, a resin sheath and a metallic sheath sequentially layered onto the surface of a conductor. A protective layer comprised by a wrapping of thermal resistant tape is formed at the surface of at least one of the insulating layer and the resin sheath. Due to the provision of this protective layer, it is possible to prevent the breakdown of the insulating layer and the formation of holes in the cable caused by pressure changes occurring when the cable is removed from an oil well within the high pressure environment.

Abstract: The present invention relates to an insulated wire comprising a conductor and at least two insulating layers provided on the outer periphery of the conductor. The inner insulating layer is provided directly or via another insulation on the outer periphery of the conductor and comprises a polyolefin compound containing 20 to 80 parts by weight of at least one substance selected from ethylene .alpha.-olefin copolymer, ethylene .alpha.-olefin polyene copolymer (.alpha.-olefin having the carbon numbers of C.sub.3 -C.sub.10, polyene being non-conjugated diene).

Abstract: A flame-retardant composition is prepared by mixing 100 parts by weight of a rubber or plastics free from any halogen with about 50 to about 200 parts by weight of magnesium hydroxide having an average particle diameter of about 0.3 to about 2 .mu.m and about 5 to about 50 parts by weight of carbon black powder having an oil absorption of about 0.5 to about 2.0 ml/g, and then cross-linking the mixture with an organic peroxide, sulfur, or a sulfur compound as a vulcanizing agent. By forming an electrical insulation and/or a sheath of the flame-retardant composition, there is provided a flame-retardant cable of the type including a cable core composed of an electric conductor coated with the electrical insulation or a plurality of such cores twisted together and covered, together with a filler, with the sheath.

Abstract: Silane-crosslinkable halogenated polymer composition and process of crosslinking the same.The silane-crosslinkable halogenated polymer composition contains a mixture including: 100 parts by weight of a halogenated polymer and about 0.1-20 parts by weight of an amino group-containing organic silane compound. The halogenated polymer composition silane-crosslinked is useful for the sheath and insulation of electric wires and cables and other moldings such as a hose.

Abstract: A flame-retardant composition is prepared by mixing 100 parts by weight of a rubber or plastics free from any halogen with about 50 to about 200 parts by weight of magnesium hydroxide having an average particle diameter of about 0.3 to about 2 .mu.m and about 5 to about 50 parts by weight of carbon black powder having an oil absorption of about 0.5 to about 2.0 ml/g, and then cross-linking the mixture with an organic peroxide, sulfur, or a sulfur compound as a vulcanizing agent. By forming an electrical insulation and/or a sheath of the flame-retardant composition, there is provided a flame-retardant cable of the type including a cable core composed of an electric conductor coated with the electrical insulation or a plurality of such cores twisted together and covered, together with a filler, with the sheath.

Abstract: The flame-retardant cross-linked composition is produced as follows: A first compound of a metallic hydrate and a polyolefin resin free from any halogen is mixed with a silane-grafted polyolefin resin free from any halogen to form a second compound; and the second compound is silane cross-linked to form the flame-retardant cross-linked composition. The metallic hydrate is mixed in an amount of about 50 to about 200 parts by weight per about 100 parts by weight of the polyolefin resin and the silane-grafted polyolefin resin, and the polyolefin resin is mixed in an amount of about (100-x) parts by weight where x is the amount of the silane-grafted polyolefin resin and about 10.ltoreq.x.ltoreq. about 80 parts by weight.The flame-retardant cross-linked composition is excellent in flame retardancy, thermal resistance and forming property and further advantageous in production cost as compared to the conventional flame-retardant composition.