Research On The Technology And Testing Method Of Seamless Knitted Fabric With Run Proof

Melt-spun spandex,a new type of elastic fiber emerged in recent years,is highly praised for its simple production process and almost zero pollution to the environment.Utilizing the property that melt-spun spandex can be melt-bonded at a certain temperature,weaving melt-spun spandex and nylon high-elastic yarn on the seamless underwear machine.Then heat-setting is carried out on the fabric,which gives the fabric good run proof function.Firstly,the thermal properties,mechanical properties and thermodynamic properties of meltspun spandex were tested by orthogonal experiment and single factor experiment.The test results show that the heat setting temperature has a great influence on the strength and elongation of meltspun spandex.The breaking strength and elongation at break of melt-spun spandex decrease with the increase of setting temperature,and the elastic recovery of melt-spun spandex increases first and then decreases with the increase of setting temperature.Secondly,the possibility of weaving the melt-spun spandex bare yarn on the seamless underwear machine and the suitable knitting technology were explored.The research indicates that the suitable tension of the melt-spun spandex yarn on the seamless underwear machine is 1.70 cN-3.12 cN;the larger the loop length ratio(nylon/melt-spun spandex)during weaving,the less the spandex content;the larger the tension of melt-spun spandex yarn on weaving,the smaller the width of the fabric after dyeing,and the thicker the fabric.Then,the test and characterization methods of nylon/melt-spun spandex fabric's run proof performance were studied,including uniaxial stretching method,biaxial stretching method,top breaking method,yarn dispersing method and the comparative analysis.The results of the uniaxial stretching and the biaxial stretching test show that the distance between the slit and the collet of the experimental instrument has a great influence on the dissociation performance of the fabric during the test.The closer the slit is to the fabric chuck,the easier the fabric is to be dissipated.In practical applications,it is better to select the biaxial stretching method or the top breaking method in combination with the yarn dispersing method.Finally,the run proof heat setting process of nylon/melt spun spandex fabrics was studied from two aspects: heat setting temperature and heat setting time.Considering saving energy consumption,improving production efficiency,elastic recovery rate and run proof property of fabrics,it is better when the heat setting temperature is 160? and the heat setting time is 80 s.The nylon/melt spun spandex fabric after 160?and 80 s heat setting was cut into a conventional shape for washing,and the fabric was still able to keep good run proof effect after washing 100 times.On the basis of this,successfully developed run proof seamless garments.