Abstract: A method for manufacturing a flame-retardant insulated wire and cable for use in nuclear power stations, comprises the steps of: extruding on a conductor or cable care to a predetermined thickness a composition consisting of 100 parts by weight of a basic polymer such as a thermoplastic resin or a rubber which can be crosslinked by an organic peroxide-based crosslinking agent, at least 10 parts by weight of a halogenated acenaphthylene or a condensate thereof, and 0.5 to 10 parts by weight of an organic peroxide; and heating a resultant wire or cable for crosslinking in the absence of water and at a temperature higher than the decomposition temperature of the organic peroxide.

Abstract: A method for preparing sheet-like, cord-like and other forms of product having excellent physical and chemical properties by mechanically pressing filmy or fibrous oriented materials of crystalline polyolefin, utilizing the pressure sensitivity of said materials.This invention relates to a method of preparing sheetlike, cord-like and other forms of polyolefin product having prominent physical and chemical properties and more particularly to a method of providing effective sheets for insulation of oil-filled power cables. Such insulation sheet is generally an oil-impregnated type whose main material is formed of pulp. However, such oil-impregnated insulation sheet which has a relatively large dielectric loss is not adapted for insulation of ultra-high voltage power cables. Recent tendency toward application of ultra-high voltage power cables demands an insulation material having a far less dielectric loss than has been allowed in the past.