Ultrasonic has been used as a cleaning vessel and a influence of powerful chemical reaction as well as to disperse dyes for many years. But recently ultrasonic has also been found to be able to improve the response rate,fabric whiteness and reduce the scouring and dyeing time. Furthermore, ultrasonic ,as a kind of ultrasonic technology which is widely used, can improve a variety of textile processing technology and has the ability to influence a variety of wet processing . Ultrasonic can also change the desizing, scouring, bleaching, dyeing, finishing and washing process. In wet processing, Ultrasonic can help to the processing time , consumption of chemicals and energy consumption and improve product quality
Ultrasonic is a kind of acoustic wave, the frequency of which is above 17khz and beyond the range of human hearing. Like electromagnetic wave, ultrasonic can refract , focus and reflect. But electromagnetic wave can propagate in the vacuum while ultrasonic propagation depends on elastic medium. In propagation, ultrasonic which makes the particles in the elastic medium vibrate and spreads energy to the direction of propagation via medium can be divided into longitudinal wave and transverse wave. In a solid, both waves can be transmitted but in the gas and liquid,only the longitudinal wave can transmit. Now dyeing and finishing mostly wet processing makes the research of longitudinal wave ultrasonic particularly important. Longitudinal wave ultrasonic can make dye dynamic boundary layer on the fiber surface thinner and accelerate the fiber surface adsorption of dye by stirring. Meanwhile it also improve the dyeing process. Though dyeing and finishing has many advantages , there are still lots of problems such as Processing and ultrasonic equipment cost, noise, ultrasonic orientation etc which need to be solved in the industrial production. We should see more about the positive aspects of ultrasonic. In recent years, ultrasonic technology has made substantial development in ultrasonic  application of desizing, boiling bleaching and dyeing in the process of ultrasonic dyeing and finishing process and he ultrasonic technique is being gradually introduced to the treatment of printing and dyeing wastewater. Thus efficient ultrasonic can not only accelerate the textile wet processing speed, improve the quality of fabric, but also save energy, improve  the environment. The so many advantages of ultrasonic decides its great potential that needs to be exploited by scientific workers