Application Of Ultrasonic Technique In Vegetable Dyes Extraction And Their Dyeing In Wool Fabrics

Ultrasonic, whose frequency is 2×10~4～2×10~9Hz, is a sound wave. Ultrasonic will produce cavitation during its propagation. Cavitation produces a kind of special energy to accelerate color matter release or fibers absorbing dyes. Therefore, research on the application of ultrasonic technique will play an important role in promoting the vegetable dyes.Firstly, this thesis took some vegetable dyes as the research objects which include HT-CT, SM-CT, HY-CT, SLZ-CT and HZ-CT, then pick out HT-CT and SM-CT whose extraction efficiency with untrasonic technique was highest through comparing with convention extraction with the same extraction process. Meanwhile the optimum ultrasonic extraction processes of HT-CT and SM-CT were established by the single factor analysis and the multi-factors orthogonal test, and then the extracting stability and the dyeing performance of extracting solution have been studied too.The research results indicated that ultrasonic extraction is a rather effective extraction process with higher extraction efficiency compareing with convention extraction. The optimum extraction craftworks of HT-CT and SM-CT are stable and feasible, have good repeatability. The color of the fabrics dyed by ultrasonic extracting solution was deeper. So the application of ultrasonic technique on the extraction of coloring matter from HT-CT and SM-CT is feasible.Secondly, this thesis took the wool fabrics as the research object and concentrated on the features of the ultrasonic dyeing on wool fabrics with ML-CT color matter and HT-CT extracting solution through comparing with convention dyeing on wool fabric with the same dyestuff. Meanwhile, the optimum dyeing processes on wool fabrics with ultrasonic were established by the single factor analysis and the orthogonal experiments.The research results indicated: the comparing experiments with and without ultrasonic showed that the ultrasonic can improve the dyeing effect, lower dyeing temperature, shorten dyeing time, and reduce the amount of dyes, it can also improve fastness of the fabrics to some extent.Thirdly, the mechnisim of promoting dyeing with ultrasonic technique has been approached through the modification of vegetable dyes, wool fiber's morphology and physico-chemical properties. The results showed that the ultrasonic radiation used in the experiment cannot alter dyestuff's shades, but it can advance the Abs of the dye liquor and the solubility of dyes obviously. The resulats also showed that the diffusion coefficients of dyes and constants of dyeing rate increase with ultrasonic treatment, which are benefit for dyeing process. Slight modificaiton of scale of wool fibers with ultrasonic treatment have been found by SEM photo, and the breaking strength of wool fabrics decrease slightly too, even though the change of chemical group of wool fibers before and after ultrasonic treatment have not been found by infrared spectrum.In a word, the ultrasonic technique used on this experimental vegetable dyes' extraction and their application on wool fabrics is quite effective. The mechanism of action of ultrasonic treatment should been approached further.