A method for the manufacture of staple fibers of oriented polyesterfaeden

摘要

992,670. Producing oriented polyester fibres. IMPERIAL CHEMICAL INDUSTRIES Ltd. April 26, 1963 [April 27, 19621, No. 16153/62. Drawings to Specification. Heading B5B. Oriented polyester filaments are produced by drawing up to 5 times their spun length in the form of a tow, the process comprising submitting melt-spun filaments issuing from a spinneret to a quenching gas stream at a distance of 0 to 10 cm. from the spinneret, followed by wetting the tow which in the form of a flattened band has a linear density per unit width in the drawn state of at least 100,000 denier per inch at draw speeds on leaving draw rolls of from 100-600 feet per minute in a pre-draw frame bath at room temperature, and lubricating the tow, followed by tensioning the tow e.g. by passage over and under fixed tensioning bars in a sinuous path, then drawing the tow by forwarding it to feed rolls, the last of which is at least partially immersed in a draw frame bath filled with aqueous liquid at a temperature of 50-100‹ C., and then through the aqueous liquid to rolls at least one of which, preferably the first, is partially immersed in the draw frame bath and rotating at a linear speed at least twice that of the feed rolls to draw the filaments in the draw frame bath at a draw ratio ranging from 2 to 5 and to give the specified orientation and draw ratio. The temperature of the gas stream may be 15‹ to 40‹ C. The temperature of the liquid in the pre-draw frame bath may be 10‹ to 25‹ C. and that in the draw frame bath 75‹ to 80‹ C. The draw zone may be maintained on the immersed surface of the last feed roll. The polyester filaments may have an intrinsic viscosity below 0.49. They may consist of polyethylene terephthalate and have an intrinsic viscosity of 0À38 to 0.47. The spinneret orifices may be circular with a diameter of 0.015 to .030 inch. The drawn filaments may have a birefringence of 180-220 x 10SP-3/SP.