Wet & heat stretching method and apparatus for acrylonitrile fibre

Abstract

The present invention provides a wet heat stretching method and a wet heat stretching device for acrylonitrile fiber bundles, which can improve productivity and can stably obtain high-quality acrylonitrile fiber bundles as raw materials for high-bulk products. In the present invention, in the wet heat stretching process of continuously stretching the acrylic fiber after the relaxation heat treatment in a humid heat atmosphere, the stretched 1kg acrylic fiber bundle is sprayed at a speed of 10 to 30m / s. Spray 50-200g of steam. At this time, the distance between the ejection port and the ejection surface of the acrylic fiber bundle was 8 to 22 mm, and the injection steam was ejected from a plurality of atmospheric pressure steam ejection ports (22a) with a diameter of 1.0 to 3.0 mm. Regardless of the thickness, even if the drawing treatment speed is high, moist heat can be applied uniformly to the entire fiber bundle, and high-quality acrylic fibers having a desired high steam shrinkage rate can be obtained.

Description

technical field [0001] The present invention relates to a wet heat stretching method and a stretching device for imparting a necessary heat shrinkage rate to acrylic fiber bundles subjected to relaxation heat treatment, and particularly relates to a method capable of imparting uniform heat energy to acrylonitrile fiber bundles in a hot and humid atmosphere and realizing The invention relates to a wet heat stretching method and a stretching device thereof with increased stretching speed. Background technique [0002] Usually, wet-spun acrylic fiber bundles are stretched once at a draw ratio of 4 to 5 times in a high-temperature washing solution in a desolventizing process, and then undergo a drying process for relaxation heat treatment (slow cooling). In order to impart high bulkiness to the final acrylic fiber product, low stretching of about 1.1 to 2 times is performed in a humid heat atmosphere after relaxation heat treatment. Usually, the wet heat stretching of this seco...

AI Technical Summary

Problems solved by technology

[0004] If the thickness (number of fibers) of the acrylic fiber bundle to be processed is not as thick as it is now, and the stretching processing speed is also low, the necessary amount of thermal energy is equalized by applying steam in the above-mentioned conventional wet heat stretching device. It is still possible to give all the fibers constituting the fiber bundles, but the thickness of the acrylic fiber bundles processed in recent years has greatly increased. In the end, it is impossible to perform a uniform treatment

This means not being able to adapt to the need to increase production speed

[0005] That is to say, if the conventional wet heat stretching device is used to obtain a necessary draw ratio at the same stretching speed, the entire constituent fibers of the acrylic fiber bundle cannot generally obtain equal heat, but heat Unevenness, not only can not be stretched uniformly, but also fiber breakage often occurs, which greatly reduces productivity

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