Abstract
To clarify the relationship between the stretch properties of weft knit fabrics and their geometrical shape factors, a comparative measurement has been made of the stress-strain behaviors of such fabrics made of spun yarn and stretch yarn.
Results: (1) The factors affecting the stretch of these fabrics are neither their loop-length, loop density nor the course wale ratio. None of these factors themselves affect it. Only their cover factor d/l does (d: apparent diameter of yarn; l: apparent loop length of fabrics).
(2) There is one master curve measured on fabrics knit in the same construction and of the same raw yarn but of different loop lengths.
Every stress-strain curve mentioned above can reach the master curve so long as it shifts along the strain-axis for the distance given by the experimental constant and cover factor.
(3) It is suggested that the deformation of knit fabrics caused by extension be considered against the master curve obtained from the above shifting method in connection with its stress-strain properties, because the said behavior depends only upon the raw material and the knit construction, irrespective of the density of knitted fabrics.
