| 摘要 |
1532626 Injecting filled resin articles BRITISH INDUSTRIAL PLASTICS Ltd 7 Nov 1975 [12 Nov 1974] Heading B5A Filled resin articles are made by injection moulding either a non-homogeneous mixture of dry amino-formaldehyde material with a filler or separate charges of the dry material and filler using a reciprocating screw injection device. The screw is effective to render the components of the working material into a homogeneous blend and the prior art necessity of forming a homogeneous blend before feeding to the injection device is obviated. The filler may be powdered, for example powdered cellulose, woodflour, talc, chalk or powdered glass or may be fibrous for example asbestos, carbon, glass or cellulose fibres. Preferred resins are methylated urea or melamine, alkylated derivatives of them, or urea, or melamine formaldehyde. Mixtures of these with unsaturated polyester resins can be used. |
