Investigation of seam performance properties of elastane denim fabrics

Denim fabrics are widely used due to their durability, comfort and convenience. Today it is seen that fabrics formed by adding elastane fiber to denim fabrics are fashionable and are preferred much by consumers. In this study, sewing performances of elastane denim fabrics sewn with different stitch type and different sewing density by using elastane core spun polyester sewing thread and polyester core spun polyester sewing thread were investigated. In the study, four different elastane denim fabrics which were 2/1 twill, 3/1 twill, 5–end satin weave constructions and %84/14/2 cotton/polyester/elastane, %75/23/2 cotton/polyester/elastane, %98/2 cotton/elastane, were used. The fabrics were stitched in weft and warp directions by using two different stitch types (lock stitch, chain stitch), two different stitch densities (3 stitches/cm, 4 stitches/cm), two different sewing threads (elastane core spun polyester sewing thread, polyester core spun polyester sewing thread). The tensile strength and elongation at break values of elastane denim fabrics selected as test specimens were determined. Seam strength test was performed on the sewn samples and sewing efficiencies were calculated. The effects of fabric type, fabric direction, sewing thread type, stitch type, and stitch density on seam strength and seam efficiency values were statistically analyzed. It was observed that the seam strength of the samples sewn by using the polyester core spun polyester sewing thread was higher than the seam strength of the samples sewn by using the elastane core spun polyester sewing thread. It has been determined that the strength of the sewing thread affects the seam strength. Seam strength of samples sewn with chain stitch was found to be higher than seam strength of samples sewn with lock stitch. Seam strength of samples stitched with a density of 4 stitches/cm was found to be higher than the seam strength of samples stitched with a density of 3 stitches/cm. It is obtained that the seam strength of the sewn samples in the weft direction is higher than the seam strength of the sewn samples in the warp direction. When the seam strengths of denim fabrics were examined together statistically; it has been determined that sewing thread type, stitch type, stitch density, and fabric direction parameters were statistically significant on seam strength, but fabric type was insignificant. When the seam efficiency values were examined, higher results were obtained by using polyester core spun polyester sewing thread. It was observed that the seam efficiency of the chain stitch was higher than that of the lock stitch. As the stitch density increased, the seam efficiency increased. It has been found that the seam efficiency in the weft direction was higher than the seam efficiency in the warp direction. The effects of sewing thread type, stitch density and fabric direction on seam efficiency values were found statistically significant. It was determined that the effect of fabric type and stitch type on seam efficiency values were not statistically significant.