Studying And Improving The Strength And Anti-pilling Property Of Super-thin Cashmere Sweater

Demand from the cashmere sweater market perspective，with the global warminggrowing, making the cashmere production develop in the weight-lighter and thinnerdirection, so the super-thin cashmere sweater meet the market demand. From the viewof fiber character, the fineness of cashmere fiber range from13to16microns,unevenness of fineness is small, average length range from35to40millimeter, it hascharacters of fine and light and soft, make it possible to develop the super-thin product.From the view of the value of product, resource of cashmere is rare and price is high,super-thin cashmere not only can save the cost, but also can show the High-gradedelicate and showily, and improve the additional value. Super-thin cashmere is favoredby foreign customers and the tops designer from the world.Paper according to the present super-thin cashmere knitting products has theproblem that there are a low yarn strength in the process of production, and a series oftechnical problems such as poor anti-pilling property, research start from theperformance of cashmere fiber, research on foundation of the cashmere productionprocess (raw materials and processing, dyeing and finishing) influence on yarn strength,this paper discusses the key technology of improving resistance strength andanti-pilling property of super-thin cashmere sweater, cashmere products not only keepthe elegant natural style, and also can improve wear ability of fabric.Paper according to the process flow of cashmere production, mainly studying onthe following four aspects of research, got a series of research results:Firstly, cashmere fiber performance index (short fiber ratio) influence on theproducing technique of cashmere products. The experiment choose different quality ofhigh count yarn, testing its tensile properties after having been finished by differentmethods (water immersion, milling). Results indicate that,short fiber ratio (content ofthe length of fiber below15millimeter) influence on the yarn reflected in two aspectsas following: first, short fiber ratio made great influence on the yarn yield. high count yarn has less fibers in the cross-section (12.5tex cashmere yarn only has50fiber in thecross-section),so short fiber ratio made directly influence on the yarn yield. Secondly,short fiber ratio made directly influence on the yarn strength(especially after themilling).in the process of milling cashmere fiber absorb water and swell， under thepressure of external forces, fibers is easy to move between each other, short fiber not behold tightly by the yarn would trend to move bigger distance, the results of the fiberrelative movement: Short length fiber would expose on the yarn surface, forming fluff.Experiments show that: yarn contains high short fiber ratio, even though its strength(184.6cN) can meet the demands of knitting, but because of short fibers moving outside,lead to structure of the yarn being broken, and fabric broken hole.Second, the yarn performance index (twist) to high count cashmere yarn tensileperformance influence. Through the variable twist factor experiment, test tensileproperties of different twist factor of cashmere yarn, comprehensive consideration ofthe cashmere fabrics fluffing and low linear density cashmere yarn for the twist factorrequirements, Explore the best twist factor for low linear density cashmere yarn. Theresults show that, the best twist factor for cashmere yarn of11.8tex×2is around310,breaking strength155cN, elongation at7.77%, yarn tensile properties meet the classyarticle requirements.Three, research on low temperature dyeing process of cashmere. Scales on thesurface of cashmere fiber held closely, the dye molecules go into fiber interior noteasily, the conventional dyeing at high temperatures. Because of cashmere fiber is verysensitive to acid, alkali, heat, In the process of dyeing, under the influence of hightemperature, fibers easily happened hydrolysis and two sulfur key rupture, and lead tofiber strength drop. the dyeing process of high count cashmere yarn，required tochoose good performance of dyes and additives，for low temperature dyeing. Paperchoose different types of low temperature dyeing auxiliaries, choose wool used of aciddyes and reactive dyes, doing low temperature of dyeing experiments of cashmere yarn,explore process of low temperature dyeing of cashmere. The analysis of experimentalresults show that, use appropriate low temperature additives, could achieve the80℃low temperature dyeing.Low temperature dyeing comparing with the conventional (98 ℃) dyeing, Yarn strength reserved rate increased around10%, K/S value and colorfastness keep the same level. Dyeing technology of acid dyes: dyestuff X%owf,Sodium Sulfate5g/l, Peregal10g/l, Low temperature agent JL-D1.0%owf, pH5.0,Bathratio1:50,Temperature80℃, time20min. Dyeing technology of reactive dyeing:dyestuff X%, levelling agent Doregal WR0.5gram, Low temperature agent JL-D2.0%owf, pH5.0,Bath ratio1:50,Temperature80℃, time20min.Four,studying on the anti-pilling finishing process of super-thin cashmere. Theexperiment chooses water-soluble polyurethane, Cationic polyamide resin class to doanti-pilling finishing with cashmere fabric, test anti-pilling finishing property and wearability, Explore the best anti-pilling finishing process of super-thin cashmere. Resultsindicate that, water-soluble Cationic polyamide resin unite with organic silicon softenerdo finishing on cashmere fabrics, Can better improve anti-pilling property and wearcomfort performance of fabric, Fabric strength reserved rate is also good. Afterfinishing, the anti-pilling property of fabric increased from three levels to four levels,Fabric bursting strength reserved rate is99.5%, drape coefficient and flexural rigiditywere down by29.5%and65%, have almost no effect of Moisture absorptionperformance, and good hand feeling.