US 4,187,352 A · Method and apparatus for producing synthetic plastics products, and product produced thereby

Abstract

A process for working up thermoplastic synthetic resin material, in particular unsorted thermoplastic synthetic resin waste material into an article having the working and processing properties of wood, and in which the material is subjected to a mixing operation in a housing including a screw member, and is fluidized, moulded, cooled in the mould, and removed from the mould. According to the invention, the synthetic resin material is supplied to an extruder without a screen member and without an extrusion nozzle, and kept therein until there is obtained a material that is fluid owing to temperature increase, and which material contains a gas when it leaves the extruder. The material is then passed into a mould having open ends, one of which is connected to the outlet of the extruder.

Claims6

Dependent claims

A method of molding articles from thermoplastic synthetic material, which comprises the steps of

(a) simultaneously introducing into an extruder apparatus having no screen member and no extrusion nozzle a quantity of a blowing agent and a mass of material at least 75% of which comprises a thermoplastic synthetic resin material;
(b) heating and mixing the components in the extruder apparatus to cause the synthetic resin material to be in a fluid condition at atmospheric pressure;
(c) introducing the mixture at atmospheric pressure into one end of an open ended mold;
and
(d) cooling and removing the mixture from the mold.

2 more elements

Dependencies are inferred from the claim text.

Method and apparatus for producing synthetic plastics products, and product produced thereby

Life of this patent

Method and apparatus for producing synthetic plastics products, and product produced thereby

Life of this patent

Abstract

Claims6