Once the polypropylene yarn is twisted, it rotates around the axis, and the long-chain polymer is twisted in the twisting direction. However, due to the fact that the arrangement between the molecules is not destroyed, the polypropylene yarn molecule internally generates a stress that restores the original shape, so that The polypropylene yarn has a twisted state, and polypropylene twisted silk of different combinations are arranged, and the polypropylene yarn produces twists in different directions, so that the surface of the fabric is uneven, and the elastic shrinkage appearance is obtained, ie, the double twisted and smooth twisted yarns are obtained. Give effect.

The purpose of shaping is mainly to ensure that the polypropylene yarn has good weavability. That is, through the shaping process, the torque of the polypropylene twisted silk can be temporarily lurked, and the warping, weft insertion, and weaving can be performed smoothly. Once the blank silk is dyed and dyed, the torque of the polypropylene twisted silk is released. The twisted state of the yarn gives the fabric an ideal twisting effect. The temporary lurking of the torque of the polypropylene yarn after twisting is referred to as a stop or setting.