Studies on needle cut and other sewing damages in single jersey knit wear

Abstract

iii newlineABSTRACT Sewing damages have been an acute problem in knitted fabrics. Sewing damage is caused when fabric restricts the penetration of sewing needle. This not only depends upon the spaces in the fabric but also needle profile, needle size, sewing machine setting and sewing thread. The consequences of such an inferior sewing of knitwear are faults which are very often recognized too late. Various researches carried out on different fabric structures varying the machine parameters and sewing thread for analyzing seam quality were mostly conducted on woven fabrics. But no comprehensive study on the effect of these parameters on knitted fabrics for the over-lock stitch is available. Thus further investigation in this regard is required and the present study is aimed at analyzing the effect of these parameters on seam quality in knitted fabric. newlineIn this work, the seam quality of single jersey knitted fabric based on needle penetration force, needle cut index, seam grinning, seam strength and seam efficiency are examined. The influence of various parameters viz. type of fiber, yarn linear density or yarn count and loop length on seam quality parameters have been analyzed. The results revealed that the polyester/cotton fabric with finer yarn count and longer loop length is known to exhibit the best seam performance among all the fabrics (100% cotton, polyester-lycra and cotton-lycra) taken for investigation. On the other hand, 100% cotton fabrics exhibit poor seam quality as cotton has more bending rigidity and a rough surface compared to other fibers, so it exposes relatively more surface area for frictional contact and needle penetration force. Thus, cotton fabric showing poor seam quality is considered for futher investigation to understand the effect of other parameters on quality of the single jersey structure. newlineFurther seam quality parameters influenced by sewing machine speed, stitches per inch and the number of fabric layers on 100% cotton fabric are investigated. It is observed that the needle cut index, sea