Abstract
Ginning and carding processes, as opening processes of cotton spinning, give both positive and negative influences on tensile properties of cotton fibers. These processes open and clean harvested fibers while result in decrease in breaking strength and breaking elongation of fibers. In this paper the changes in tensile properties from the opening process to steps of repeated washing/drying of garments were measured and analyzed based on the results of tensile tests on individual cotton fibers. We ginned cottons with three ginning rates and analyzed the tensile properties. It seemed that a certain threshold value of processing rate exists for showing critical detrimental effects on breaking strength of individual fibers while higher process rate resulted in increase in breaking elongation. Compared to tensile properties of hand-ginned cotton, processes performed by opening machine damaged tensile properties of fibers significantly. Subsequent processes (carding, before/after garment laundering) in addition to the ginning process also influenced the tensile properties significantly. While the tensile strength of individual fibers decreased during spinning and knitting processes, the breaking elongation decreased significantly during repeated laundering stages. These phenomena can be explained by the fact that dry processes affect tensile strength while wet processes tensile elongation of individual fibers.