Abstract
This study aims to make distinct the difference between cotton threads and polyester-spun threads on the tensile strength of seams in cotton fabrics. Experiments were performed in the same methods as that used in Part 1. The critical values of the seam breakage were measured with the tensile tester (CRT Type). The results are as follows : The deterioration ratio of seam strengths is remarkable for the polyester-spun threads than that of the cotton threads, but the seam strengths of polyester-spun threads were stronger even after washing twenty times. The polyester-spun threads were more reasonable than the cotton threads for machine sewing of cotton fabrics, as far as looks, tensile strengths, external appearance and price were concerned.
