| 摘要 |
540,748. Tubular films. HEAVEN, H. S. April 26, 1940, No. 7570. [Class 2 (ii)] Tubular film, formed by the extrusion of a cellulosic solution into a coagulating bath, is led past a grubbing member or members which make contact with the inner or the outer surface of the tubular body, or with both surfaces, and restrict the flow of coagulating liquid along the tubular body. The rubbing members are supported in line with the spinning nozzle and may be expansible and contractible so as to fit the tube being extruded. As shown a rod 20 extends upwards from the spinning nozzle 13 immersed in a coagulating bath 11 and supports a plug 22 above the level 12 of the liquid in the bath : the plug is hollow and has outer flexible walls 23 which can be expanded by water or other fluid introduced from a pipe 21 extending through the rod 20. A second pipe 121 also extends through the rod 20 and terminates just above the plug for draining the tubular body. The exterior of the tube is rubbed by a scraper or die 25 formed by a circularlyapertured plate surrounding the plug 22 at its greatest diameter : the aperture may be formed by an iris diaphragm so that the diameter thereof can be varied. The scraper may be formed of a cord of circular cross-section or of a tubular rubber ring which may be expanded to vary the diameter of the aperture. A conical shield may be arranged above the scraper 25 to catch any washing water which flows down the outside of the tube and prevent it falling into the coagulating liquid. Two or more plugs and scrapers may be arranged along the length of the tube with provision for the controlled inflation of the plugs and separate tubes may be provided for the plugs for the removal of gas and liquid from the interior of the tubular body. |
