Research On The Plating Effect And Properties Of Plated Knitting Fabrics Of New Filament

With the rising of consumptive level, elasticity is urgently needed as an essential element for wider range of clothes. Nowadays, spandex is the most widely used material all over the world because of its excellent elasticity. Owing to the high price, big investment, the complicated spinning process and other reasons, it is necessary to develop the elastic yam with lower elasticity and fabric to meet customer's requirement.In this thesis we mainly study the performance of PTT filament, the knitting process and the wearing characteristics of PTT plated knit goods. PTT is the abbreviation for 'polytrimethylene terephthalate', whose elasticity is lower than that of spandex but higher than that of normal PET. It is one kind of modified polyester and also belongs to the polyester family as PET. It integrates almost all the fine properties of other synthetic fibers, such as the chemical-resistant of PET, the softness and elasticity of PA, and the bulkiness of acrylic. Therefore, more attention has been paid to PTT. PTT filament has been used in many fields now, such as carpet, non-woven fabric and plastic for engineering as well as in the field of apparel especially for high-level knitted clothes and functional fabrics because of its good flexibility and softness. Nowadays, PTT has become one of the most new popular materials in the world.With the development of knitting industry and novel fiber materials, more and more weft-knit plated knit goods are used in the fields of clothing, decoration and technical textiles, especially in the functional underwear, casual knits and medical textiles. These plated knit goods produced in circular and flat knitting machines characterize the properties of both plating yam and ground yarn and have the color effects on both sides. During the production of plated knit goods, there are many factors influence the fabric properties and plating effects such as physical and mechanical properties of fiber and yarn, feeder construction and position, needle shape, knitting action, tension of yarn feeder supply and drawn-off mechanism etc. The research of this paper is focusing on the newer PTT plated knit goods and discusses about its knitting techniques and wearing characteristics. One of the aims of this study is to validate the traditional plating theory and plating techniques by knitting experiments whether they are suitable for PTT plated knit goods produced from B.C.M 16 diameter circular knitting machine. It has significant meanings for applying plating knit goods to clothing uses.The main studies of this thesis are as follows:1 Analyzed the possibility and marketing value of PTT filament in the use of knitting lower elastic plated knit goods.2 Tested the strength/elongation of PTT and compared it with that of PET and silk to analyze the possibility of application of PTT in plating knit goods again by the views of actual experiments.3 Discussed the plating theory and plating techniques which are suitable for PTT plated knit goods produced from B.C.M 16 diameter circular knitting machine in 2 aspects: theory analysis and actual experiments. We first tried to make use of the original feeder on the machine to knit the fabric, but this kind of feeder made it harder for us to change the yarn laying angles of both plating yam and ground yarn at vertical and horizontal planes and we failed to obtain the fabric whose platting effect is good. So we additionally installed a small chain wheel which is used for knitting spandex fabrics into the original feeder of the machine to combine as a new feeder. The new feeder not only avoided the difficulty of changing the yarn laying angles, but also reduced the abrasion created by the PTT filament because of its elastic threading through the hole of the original feeder. The device helps to gain the sound plated knit goods.4 Measured the final plating effect of the PTT plated knit goods by the ways of digital photography observation and drawing the cross-section tracks pictures of both plating yarn and ground yarn with the help of Matlab program. The Matlab program was based on the precise analysis of the Space Analytic Geometry Principle and we also took some pictures of the fabrics to help compare the plating effect directly, from which aspect the results we got were similar.5 According to the properties of PTT, we tested the wearing characteristics of the PTT plated knit goods and compared it with that of other ordinary plated knit goods such as silk-covered cotton fabrics and polyester-covered cotton fabrics, especially the elongation and elastic properties of these three kinds of fabrics, which came to a conclusion that the performance of PTT plated knit goods knitted by B.C.M 16 diameter circular knitting machine mentioned in this thesis was good and the fabric was suitable for apparel.Generally, the value proposition of PTT filament in textile apparel applications was described by testing and analyzing of the properties of yarn, knitting techniques and the performance of fabric. We hope all of these will provide a solid foundation for the development and application of PTT in the near future.