Improvements in and relating to the manufacture of artificial threads, fibres, filaments and the like

The ultra-violet light stability of polydienesulphur dioxide threads is increased by passing the thread during its manufacture in a number of consecutive turns over one or more thread-advancing, thread-storage devices and subjecting the turns of thread to an extensive washing treatment with a liquid consisting essentially of an alcohol. The polydiene may be polybutadiene or natural rubber. The thread-storage devices are preferably reels of the type described in Specifications 413,413, 413,414, [Group IX], and 474,974. The alcohol, which may be ethanol, methanol or isopropanol, on the thread-storage device preferably flows in counter-current to the direction of travel of the thread. The washing step may be followed by the incorporation of heat-stabilizing agents such as those disclosed in Specifications 666,640 and 684,967. In examples, masticated rubber in toluene is activated with tertiary butyl hydroperoxide and then extruded into a coagulant bath containing sulphur dioxide dissolved in a mixture of ethanol and toluene; the resultant thread is passed to a take-up godet and then over three cantilever thread-advancing reels on the first two of which the thread is washed with ethanol. On the third reel the thread is washed with ethanol alone, or with ethanol containing either thiourea and hexamethylene tetramine or phenyl salicylate. Specifications 527,075, 616,276, and 679,274 also are referred to.ALSO:The ultra-violet light stability of polydiene-sulphur dioxide threads is increased by passing the thread during its manufacture in a number of consecutive turns over one or more thread-advancing, thread-storage devices and subjecting the turns of thread to an extensive washing treatment with a liquid consisting essentially of an alcohol. The thread-storage devices are preferably reels of the type described in Specifications 413,413, [Group IV], 413,414, [Group IX], and 474,974, [Group IV]. The alcohol which may be ethanol, methanol or isopropanol on the thread storage device preferably flows counter-current to the direction of travel of the thread. The washing step may be followed by the incorporation of heat stabilizing agents such as those disclosed in Specifications 666,640, [Group IV (a)], and 684,967. In Examples, masticated rubber in toluene was activated with tertiary butyl hydroperoxide and then extruded into a coagulant bath containing sulphur dioxide dissolved in a mixture of ethanol and toluene, the resultant thread was passed to a take-up godet a