The Empty Core Yarn And Product Development

"Hollow" yarns have the properties with light-weight, flexible and more warm,as increased the entrapped air in the yarn, and to gain a stronger yarn for spinning and weaving processes. Hollow yarns are spun on a spinning frame that has been modified. A PVA yarn is used as the core and cotton fibers form the sheath .The water soluble PVA in the center is removed from the yarn structure in the boiling water with a good extraction of move than 90%.In this paper, we have analyzed and investigated the characteristic of water soluble PVA fiber and transformed the spinning frame AS511.We have explored the method of producing a hollow yarn by testing and analysing the yarn and knit clothes. The experimental result are compared with conventional pure cotton yarn and blended yarn and their clothes, some conclusions had been drawn:1. Producing PVA/Cotton core-yarn in modified AS5 11 ring spun yarn machine is feasible, and the sheath fiber hide the core completely .The PVA yarn as the core and the cotton fiber as the sheath are interlaced, which is helpful to set the boiled hollow yarn. The factors that affect the core coverage are the tension of fed PVA yarn, the gauge between the two cotton strands, etc.2. The factors that affect the hollow result of boiled yarn are the twist multiplier of core yarn, the percentage of the core, the kind of PVA fiber and the core coverage of core-yarn.3. After PVA are completely extracted, the strength of hollow yarn is lower than conventional cotton yarn, and the strength of hollow yarn is increased and then decreased with the boiling time going.4. After boiled, the extraction of PVA is more than 90%.5. The bursting strength of knit fabric using hollow yarn is lower than using conventional cotton yarn. The bursting strength of former is 24kgf, the bursting strength of later is 33kgf.6. The air permeability of knit cloths using hollow yarn is better than usingconventional cotton yarn. Because hollow yarn is loose, its knit cloths feel soft.7. The experimental results of water absorption and drying rate show that knit fabric using hollow yarn imbibe more water than using conventional cotton yarn, and with the same percentage water ,hollow yarn knit cloths will be dry more fast.8. The hollow center of the yarn produced in this experiment has a poor fixation. After many times washed, the middle hollow center is destroyed, which is related to the kind of PVA fiber and the extraction process. As to the fixation of hollow yarn ,it needs further exploration and test.