| 摘要 |
<p>541,261. Treating yarns &c. CARBIDE & CARBON CHEMICALS CORPORATION. July 23, 1940, No. 12037. Convention date, Oct. 25, 1939. Addition to 518,710. [Class 120 (iii)] [Also in Group IV] Threads, or yarns made from a vinyl resin obtainable by the conjoint polymerisation of a vinyl halide with a vinyl ester of an aliphatic acid and having an average macromolecular weight of at least 15,000 are given increased tensile strength by being passed continuously through a liquid or vapour which will not attack or dissolve the resin, the temperature of the liquid or vapour being at least 100‹C. and the threads being stretched as they pass through it while surface wetted with a non- solvent for the resin; the liquid or vapour may be heated to a temperature between 100‹ and 130‹C., may be wet steam, and the threads may be stretched up to about 600 per cent. The threads may be passed continuously through a non-solvent liquid heated to a temperature in excess of 100‹C. and stretched while in contact with and wetted by said heated liquid. The resin is preferably that obtainable by the conjoint polymerization of vinyl chloride and vinyl acetate, containing about 70 to 95 per cent. by weight of vinyl chloride in the polymer and the threads may be stretched while passing continuously through 'diethylene glycol heated to a temperature in excess of 100‹C. and while in contact with and wetted by the heated diethylene glycol. As shown a yarn 10 is drawn from a supply bobbin 11 by a bobbin 13 driven by a roller 14 and is wound up by a bobbin 25 driven by a roller 26 with a peripheral speed several times that of the bobbin 13 to impart the desired stretch to the yarn. The yarn makes half a turn around the bobbin 13, passes over a pulley 15, around the bobbin 13, again and then passes through a chamber 16 provided with a steam inlet 17 and thermometer 18, the yarn is heated, wetted, and stretched in the chamber and passes therefrom over pulleys 19, 20 to a pulley 21 immersed in a cold water bath 22 from which it passes to the traverse guide 24 of the bobbin 25. In a modification the supply bobbin is driven, the yarn is lapped several times around a positively driven roller in a heated bath and an idler roller and passes from the bath to the winding-up bobbin.</p> |
