| 摘要 |
711,266. Agglutinated fibrous materials. SOC. ANON. DES MANUFACTURES DES GLACES ET PRODUITS CHIMIQUES . DE ST.-GOBAIN, CHAUNY. & CIREY.April 5. 1950 [April 5. 1949 ; March 25, 1950], No. 8572/50. Drawings to Specification. Class 140 Sheets or bands of plastic materials reinforced with fibres of glass or analogous mineral material. arranged parallel or substantially parallel and wound on a rotating member such as a drum. which serves to attenuate the fibres, are made by applying the plastic material to the fibres, before or during winding on the drum. in the form of an emulsion which is thickened or rendered consistent in such a manner that, in spite of the action of centrifugal force due to rotation of the rotary member, and the loss of , emulsion which may leave the drum during rotation, the quantity of material which is retained on the fibres on the drum is sufficient to obtain in the finished sheet or band between 30 per cent. and 85 per cent. thereof in volume proportion relative to the total volume of the sheet or band. The thickening may be brought about by mixing with the emulsion, e.g. an emulsion of polyvinyl chloride or a co-polymer thereof, a naturally viscous material such as gum arabic alginates, or polyvinyl alcohol, or substances capable of causing a commencement of coagulation, e.g. electrolytes, such as strong acids or bases, salts such as sulphates or chlorides. or sallts of metals with a strongly positive cation, e.g. calcium. barium, strontium, magnesium, zinc or aluminium chloride. Substances, the presence of which in the finished product is objectionable may be removed by washing or destroyed by treatment with a suitable reagent, e.g aluminium sulphate may be caused to react with baryta water. The emulsion and the substance producing the thickening may be applied to the fibres before or during their contact with the drum, or both, as by spraying. or the thickening substance may be applied, before the fibres reach the drum. by means of a device provided with felt saturated therewith, and, where the thickening substance is an electrolyte which is to be destroyed by reaction with a suitable reagent, both these may be applied by successive sizing rods before the fibres reach the drum. A solution of a plastic material capable of adhering to that in the emulsion, e.g. of polyvinyl chloride or after chlorinated polyvinyl chloride when using an emulsion of polyvinyl chloride or a copolymer thereof, may be applied to the fibres or to the drum. or both, prior to application of the emulsion, and the sheet heated thereafter. |
