Study On The Dimensional Stability Of Seamless Knitted Underwear

Seamless knitted Underwear is knitted in the special equipment for production of a novel shaping underwear, which is used to produce high elastic knitted outerwear, underwear and sportswear with high elasticity, so that neck, waist and hip joints and other parts without seem. Seamless underwear will be comfortable, thoughtful rolled into one, with wear fit, style, fashion novel features, which have achieved great development. It uses a fixed cylinder diameter and pin number, and through the change of raw material and the organization of made the three-dimensional fabrics obtained the acceptance of the consumer; there are great prospects for development. However, in the processing of weaving factory, seamless underwear dimensional stability has become a troubled problem that effect enterprise development.This thesis first introduces the knitting and the principle of main organizational structure of seamless underwear, the traditional seamless underwear are made of spun-yarn, cotton yarn, or woven nylon, etc., followed describes some factors that effect the weaving process.From the geometric structure, the change in size of knitwear is mainly reflected in changes in density, while the seamless underwear dimensional stability is influenced from the coil length, diameter, yarn, dyeing and finishing, etc. causes a change in the internal structure of knitted fabrics over the past affect the size. In this paper, we first respectively test spun-yam, nylon, coolmax yarn at different temperatures under humid conditions, the contraction of the situation, obtained by experiments dealing with the best fabrics water bath temperature within a certain range is now complicated by shrinkage yarn increases with rising temperature.Combined company's actual problems in the production of seamless underwear, as well as the reasons for the special finishing, followed, this paper examines the woven seamlessly within the different modes of post-treatment and found that after full relaxation of thermoplastic fabric through the post did not meet the their final steady-state; and then explored the fabric density through the various water bath, drying temperature conditions, and obtained optimal temperature of bath that deal with seamless underwear shrunk.To further study the mechanism that effect fabrics dimensionally stable, the subject through the use of the rate of expansion rate, temperature, time, raw materials four factors, each factor to take 4 level orthogonal tests, obtained optimal fabric heat setting process, which helps to reduce the defect rate, and reduce costs. In this paper, on the basis of the four levels of four factors experiments, but also carried out a three levels except raw materials the three-factor orthogonal experiment, this time, select the rate of expansion rate, temperature and time as the three orthogonal factors, each factor Select the three levels of testing, and take the fabric breaking strength, breaking elongation and density of the shrinkage rate as the evaluation index, and then analysis of variance on the experimental results obtained effects of various factors on finishing the degree of influence.Finally this paper, we carry out the test analysis of mechanical properties and dimensional stability performance of the seamless underwear after the heat setting, after that we adopted fuzzy decision-making and fuzzy clustering analysis of the fabric after heat setting do a comprehensive analysis and evaluation.