Pilling is related to the fabric structure, for example, knitting is easier to pilling than weaving, and loose structure is easier to pilling than tight structure. At the same time, pilling is also related to the raw materials of the fabric. The materials with good strength, good fatigue resistance, smooth surface and fine texture are easy to pilling, because the reason for pilling is that the fiber tip slides out of the fabric to form hairiness, and the hairiness entangles with each other to form a ball. Raw material feather with poor strength falls off before entanglement, and raw material feather with less smooth surface is not easy to slip out of the fabric. If we make a ranking of pilling ease, it is probably as follows: nylon>polyester>acrylic>wool>rayon>spun silk>cotton>cywarch. Yn ôl y safle uchod, nid yw 95 y cant cotwm a 5 y cant spandex yn hawdd i'w pilsio. Dim ond rôl elastigedd y mae Spandex yn ei chwarae, yn gyffredinol yng nghraidd edafedd, ac nid yw'n cael unrhyw effaith ar bilsio.
