| 摘要 |
Crimped threads, fibres and like products are made by spinning viscose having a cellulose/alkali ratio of at least 10/6, in the presence of a surface-active substance, into a bath containing sodium sulphate, zinc sulphate, sulphuric acid in concentration less than 1.4 times the alkali content of the viscose and 0.5-5 per cent of ammonium sulphate, the formed threads being stretched and finally tension-released in a swelling agent. The surface-active agent, which may be added either to the viscose or to the bath, may be anion-active, cation-active or non-ionogenic, those of the formula <FORM:0799718/IV (a)/1> (wherein R represents an alkyl group with 8-20 carbon atoms, x+y has a value between 5 and 50, and either x or y may be zero but is not necessarily so) being preferred. Other specified surface-active agents are lauryl triethyl ammonium chloride, "Prestabit" oil (Registered Trade Mark) and lauryl pyridinium chloride. Specified swelling agents are hot water, dilute caustic soda and glycerol. In an example, to viscose with a cellulose content of 8.6 per cent and an alkali content of 4.8 per cent is added 0.3 per cent of a surface-active agent of the formula above. and the viscose is spun at 50 DEG C. into a bath containing 4.5 per cent of sulphuric acid, 20 per cent of sodium sulphate, 1.5 per cent of ammonium sulphate and 1 per cent of zinc sulphate. The resulting thread is stretched 50 per cent in water at 90 DEG C. and then cut into fibres. Immersion in water at 90 DEG C. caused spontaneous crimping. |
