(1) Recovery of fiber deformation under moist heat state. When cotton knitted fabric is washed in a relaxed state, water molecules can destroy the newly generated hydrogen bonds, relax the internal stress, and shrink the elongation part by shrinking.
⑵ recovery of knitted fabric deformation. When the knitted fabric structure is far away from the stable state of the knitted fabric, when wetting and washing, the plasticity of the fiber is enhanced, and the restoring force is strengthened, resulting in deformation recovery, elongation and retraction, and cotton knitted fabric shrinks and returns to the original stable state. . This is the main reason for the shrinkage of cotton knitted fabrics.
(3) The fiber absorbs moisture and the diameter of the yarn increases, causing the yarn to shrink and shrink. The increase in yarn diameter causes the length of the yarn to shorten, causing the fabric to shrink (both length and width) and increase in density.
The above are the basic reasons for the shrinkage of cotton knitted fabrics. As for knitted fabrics, the influencing factors and shrinkage conditions of knitted fabrics under different conditions, such as: knitted fabrics with different fiber components, knitted fabrics with different organizational structures, different dyeing and finishing processes and equipment, whether the fabric has undergone mercerization, tenter setting and pre-processing It still needs to be explored, summarized, improved and improved in practice.