Abstract
Repeating loading is presumed to be one of the cause of seam damages.
In this study, the decrease in seam strength after repeated loading was investigated for Kimono cloths sewed with Naminui stitch (JIS L 0120-1984; 209).
It was found that the degree of damages varied with the kind of cloth and stitch length. Especially in the case of wool cloth with high strain recovery, heavier damages were observed for lower stitch densities.
Loading perpendicular to seam caused seam grinning. When the fabrics has high elastic recovery, the seam grinning disappear by unloading. This behavior was connected with the decrease in seam strength.
It was concluded that sewing threads were mainly damaged by the friction between threads and fabrics during repeating loading due to high elastic recovery of wool fabrics.
