The effect of core-sheath proportion on the characteristics of hollow yarns: part I mechanical properties

In the scope of this study, core yarns in the yarn count of 59 tex were produced by using cotton, viscose, wool, and polyester fibers in the sheath and different ratios of polyvinyl alcohol (PVA) in the core. After completion of yarn production on ring spinning frame, winding process was performed in order to get packages. These yarns in the form of packages were washed during a time period in order to remove PVA from the yarn structures to obtain hollow yarn structure. Yarn irregularity and yarn tensile tests were performed in the form of packages before and after washing process. As a result of these tests; it was observed that values of yarn unevenness and tensile tests were significantly influenced by the core-sheath proportion and washing process.