Study On The Test Method Of Ratio Of Droppings And Performance Of Weft Knitted Fleece Fabrics

Weft knitted fleece fabric has excellent characteristics such as good elasticity,softness and comfort,excellent heat preservation,etc.However,in the process of wearing and washing,the surface fluff of the fabric is easy to fall off,which seriously affects the appearance and service life of the weft knitted fleece fabrics.At present,there is a lack of relevant testing standards for ratio of droppings weft knitted fleece fabrics in China,and the quality of products on the market is mixed,which makes it difficult to protect the rights of consumers.In this paper,several common weft knitted fleece fabrics in the market are selected,and the testing method of ratio of droppings is selected.The factors that affect the ratio of droppings of weft knitted fleece fabrics and the anti-dropping finishing process are studied,so as to provide reference for the evaluation of ratio of droppings of weft knitted fleece fabrics and product development.Firstly,the common weft knitted fleece fabrics on the market were selected for quantitative ratio of droppings testing to preferably select the ratio of droppings testing method,and the subjective evaluation method of ratio of droppings was designed to test the feasibility of the preferred testing method.The single-factor analysis method was selected to determine the test parameters range of circular track fabric abrasive method,circular track nylon brush method,martindale small head method,martindale medium head method,martindale large head method and rolling box method,etc.;YG502 fabric pilling meter,M235 Martindale abrasion tester and rolling box pilling meter were used to test the ratio of droppings of the specimens,and by calculating and analyzing the ratio of droppings,ratio of droppings difference and CV value of the specimens,the preferred test method and parameters of ratio of droppings are determined;using the subjective evaluation method of ratio of droppings and the preferred test method and parameters,the weft knitted fleece fabrics is tested at the same time,and the experimental results obtained are basically the same.Therefore,it is determined that the test method of ratio of droppings of weft knitted fleece fabrics is martindale medium head method,and the experimental parameters are weight pressure 155 c N and rubbing times 1000 times.Secondly,to explore the effect of cotton fiber length,fabric spandex content,number of dipping and rolling in anti-droppings finishing,type of softener in softening finishing,as well as fleece tension,ironing roller temperature,ironing roller coverage in fleece and ironing processes on the ratio of droppings of weft knitted fleece fabrics.The results showed that the ratio of droppings of weft knitted fleece fabrics decreased with the increase of cotton fiber length in weft knitted fleece fabrics.Spandex woven into the fabric with full lining will reduce the fabric droppings,and the greater the proportion of spandex in the fabric,the ratio of droppings of weft knitted fleece fabrics is smaller;in the anti-droppings finishing process,the more times of dipping,the better the finishing effect,the more times of rolling,the worse the finishing effect.In common dipping and rolling finishing,a dipping and two rolling compared to a dipping and a rolling hair rate increased by 16.2%,two dipping and two rolling compared to a dipping and a rolling hair rate decreased by 29.7%,so in order to obtain better finishing effect,can increase the number of dipping;different types of softener finishing the ratio of droppings of weft knitted fleece fabrics from more to less: large molecule silicone oil softener finishing > small molecule silicone oil softener finishing > hydrophilic silicone oil softener finishing > soft sheet softener finishing >without softener finishing;fleece process,the fleece process into the cloth tension increases,the ratio of droppings increased;ironing process of the ironing roller temperature increases,the first hair decreased and then increased,the ironing roller covering degree increases,the first hair decreased and then increased,so to choose the appropriate into the cloth tension,ironing roller temperature and ironing roller covering degree and other fleece process parameters,in order to get the best finishing effect.Then,the best anti-droppings finishing process for weft knitted fleece fabrics was explored.For the interlock weft knitted double-sided brush fleece fabrics provided by the enterprise and the new anti-shedding finishing agent RRP01 for anti-droppings finishing,with ratio of droppings,thermal resistance,bending stiffness as evaluation indexes,the effect of finishing process parameters such as impregnation concentration,impregnation temperature,baking time and baking temperature on ratio of droppings,thermal resistance and bending stiffness was investigated by single factor analysis,four factors and three levels of orthogonal experiments were used to obtain the best anti-droppings finishing process parameters for weft knitted fleece fabrics: impregnation concentration of 2%,impregnation temperature of 40?,baking time of7 min and baking temperature of 140?.Finally,the best anti-droppings finishing process was selected to finish the interlock brush fleece fabric with double rib weft knitting,and the effects of anti-droppings finishing process on the fabric's drape,bending,bursting,shearing,compression,tensile,pilling,dimensional stability,physiological comfort and air permeability were compared and tested.The results show that the finished fabric has excellent bursting strength,shear performance,heat transfer performance and dimensional stability,and the percentage changes of the test indexes of each performance are16.6-16.7%,7.1-7.3%,33.7-37.3%,0.6-3.2% respectively.After finishing,the anti-pilling property of the fabric becomes better,and the anti-pilling grade is reduced by one grade;The drape property,bending property,compression property,tensile property,moisture transfer property and air permeability of the fabric are slightly deteriorated,and the percentage changes of the test indexes of each property are 6-14%,4.4-10.7%,8.3%,0.3-15.5%,2-11% and 13.1%respectively,due to the excellent softness,mechanical properties and air permeability of weft knitted fleece fabrics,the anti-droppings finishing has no great influence on fabric properties.