The factors influencing pilling of sweaters 1. The influence of yarn The more curved waveforms a fiber has, the less likely it is to stretch during twisting, and the more likely it is to loosen and slip during the friction process, forming fuzz on the surface of the yarn. For this reason, the better the flexibility of the fiber, the more likely it is to pill. The finer the fibers, the more fiber ends are exposed on the surface of the yarn, and the better the softness of the fibers. Therefore, fine fibers are more prone to entanglement and pilling than coarse fibers. 2. The influence of fabric structure Fabrics with loose organizational structures are more prone to pilling and fuzzing than those with tight structures. High-number fabrics are generally more compact, so low-number fabrics are more prone to pilling and fuzz than high-number fabrics. Fabrics with a smooth surface are less prone to pilling, while those with an uneven surface are more likely to do so. 3. The influence of dyeing and finishing processes After dyeing and finishing, the pilling property of yarns or fabrics will be significantly affected, which is related to the dyes, auxiliaries and dyeing and finishing process conditions. Yarns dyed with twisted yarns are more prone to pilling than those dyed with loose fibers or wool streaks. Fabrics dyed with finished garments are more prone to pilling than those dyed with yarns.