GB856120A - A method of manufacturing antistatic plastic mouldings - Google Patents

Abstract

A moulded article having a surface on which the accumulation of static electricity is prevented is made by a process in which a core of a powdered synthetic powder selected from polyvinyl chloride, a vinyl chloride-vinyl acetate copolymer, a methacrylic resin, polyethylene, and polystyrene is coated with a synthetic resin powder containing an antistatic agent, and the coated core is hot-pressed between moulds. When the core is of polyethylene or polystyrene the article may, alternatively, be made by preforming the core between moulds coated with a solution of an antistatic agent of the quaternary ammonium salt type, and the preform then transferred to a press in which it is moulded between heated moulds. The quaternary ammonium salt may consist of stearamidopropyldimethyl-b -hydroxyethyl ammonium nitrate. Other antistatic agents specified are of the alkylpyridinium salt, aliphatic alcohol phosphate, polyoxyethyleneglycol alkyl ester, polyoxyethylene glycol, ether, sorbitan fatty acid ester, irridazoline, and betaine types. In one method described in the examples a thin layer of synthetic resin impregnated with antistatic agent is placed on each side of a core tablet and the assembly moulded under heat and pressure. In another method a solution of the antistatic agent is sprayed on to the core tablet prior to moulding under heat and pressure.