| 摘要 |
824,572. Agglutinated fibrous materials. UNITED PLASTIC INDUSTRIES Inc. April 15, 1957, No. 12211/57. Class 140. A method of bonding fibres together is characterized by impelling powdered thermoplastic resin particles into an advancing layer of fibres by striking the said particles with rapidly rotating impelling surfaces and directing the particles as a stream along with a stream of air into the said advancing layer of fibres, so as to impregnate the layer with powdered resin and thereafter heating, compressing and cooling the impregnated layer. In an illustrated embodiment a slotted conveyer belt 36 carries a layer of fibres (not shown) beneath an impeller comprising a generated rotor 48. A shield 52 which embraces the rotor and fits closely round it, has a discharge slot 56 and an inlet slot 54 extending parallel to the axis of the rotor. Feeder pan 60, containing powdered resin binder, is continuously vibrated by drive 63 so as to feed resin into shoot 58, whereby it is conducted to the rotor. The shoot 58 is oriented so that it gives rise to an air injection action on the resin particles, which are thus sucked down the shoot. The resin particles and air are expelled through the discharge slot 56 in a downward direction opposed to the direction of movement of the layer of fibres, so that the resin particles strike and pass into the layer of fibres. Two impellers may project resin in opposite directions. The layer of fibres may be made up by combining the two layers issuing from a twin-doffer garnet machine. After impregnating with resin particles the layer may be cross-lapped to form a composite multiple layered mass and then subjected to heat and pressure as e.g. by means of heated calender rolls. Before cross-lapping the layer may be corrugated by heating and passing through mating corrugating rollers or a single corrugating roller meshing with rods of the conveyer. The resin may be applied to the layer after corrugating the latter. The resin feeding apparatus or the impeller progress may be arranged so as to apply more resin towards one edge of the fibrous layer than towards the other. This result may be accomplished by constructing the impeller rotor in the form of a truncated cone. Vegetable or animal fibres may be used, cotton being specifically mentioned. The binder resin may be a co-polymer of vinyl acetate and vinyl chloride. Specification 787,073 is referred to. |
