High speed spinning of viscose filament yarns

This article discusses the evolution of high-speed viscose yarn spinning with emphasis on the technology developed by the Germany company Enka during the 1990s. Current technologies are detailed for comparison, as is the specific quality requirements for viscose filament yarns. Eka has reduced these requirements to just three basic yarn properties of constant dye uptake, consistency in physical properties of the yarn, and the best mechanical processing properties that can be achieved. The text is illustrated with four figures showing selected aspects of the technology. The processes involved in high-speed spinning are discussed in detail up to the drying process. The Enka technology has been developed with the aid of a pilot plant running for the last two years. The company is convinced by its results that 500 metres/minute is an optimum speed to achieve a good compromise between running efficiency and process stability (few breaks), although the technology is capable of higher speeds.