GB527532A - Spinning of artificial filaments or films - Google Patents

Abstract

527,532. Spinning artificial filaments. DU PONT DE NEMOURS & CO., E. I. April 14, 1939, Nos. 11320 and 11321. Convention dates, April 27, 1938 and Feb. 18, 1939. [Class 2 (ii)] Filaments, ribbons, foils &c. are formed from molten polyamides and other filamentforming compounds by forcing one or more uniformly shaped solid rods composed of such materials through corresponding apertures of smaller cross-sectional dimension than the rods into a chamber containing heating surfaces adapted to melt only the inwardly projecting ends of the rods and ejecting the melted material through openings of the desired shape to form filaments &c. The exposure of the materials to a melting temperature for an extended period of time is thus avoided, uniformity of denier is secured, and contact of melted material with moving parts eliminated. Fig. 7 shows a form of apparatus suitable for continuously feeding molten filament-forming material to a spinneret. The rods 1, 1<SP>1</SP> of material are forced by screwoperated caps 4, 4<SP>1</SP> through sealing rings 3, 31 of slightly smaller diameter than the rods into contact with the walls 5, 5<SP>1</SP> of a melting chamber 2, the temperature at the walls 5, 5<SP>1</SP> being maintained somewhat above the melting point of the rods by heating coils 6. Cooling coils 13, 13<SP>1</SP> are provided to keep down the temperature of the sealing rings 3, 3<SP>1</SP>. The molten material is forced through filters 11 to the spinneret 9. In order to secure continuous action, the rods 1, 1<SP>1</SP> are forced into the chamber in succession, one or other of the valves 51, 52 being closed when necessary to permit a new rod of material to be inserted into the machine. In cases where the material of the rod requires it, a supporting cylinder may surround the rod and the screw-operated caps be replaced by plungers or pistons. Among the filament-forming materials mentioned as suitable for the process are polytetramethylene sebacamide, polyhexamethylene suberamide and sebacamide, polydecamethylene and polyhexamethylene adipamides and the polyamide from 6-amino-caproic acid ; polyethylene, polystyrene, polyacrylic acid, polyesters, polyethers, polyacetals, mixed polyester-polyamides, and cellulose derivatives such as plasticized cellulose acetate can also be spun by the method. U.S.A. Specifications 2,071,250, 2,071,253 and 2,130,948 are referred to.