Pill (textile)

A pill, colloquially known as a bobble, is a small ball of fibers that forms on a piece of cloth. 'Pill' is also a verb for the formation of such balls.

Pilling is a surface defect of textiles caused by wear, and is considered unsightly. It happens when washing and wearing of fabrics causes loose fibers to begin to push out from the surface of the cloth, and, over time, abrasion causes the fibers to develop into small spherical bundles, anchored to the surface of the fabric by protruding fibers that haven't broken. The textile industry divides pilling into four stages: fuzz formation, entanglement, growth, and wear-off. Pilling normally happens on the parts of clothing that receive the most abrasion in day-to-day wear, such as the collar, cuffs, and around the thighs and on trousers.

All fabrics pill to some extent, although fibers such as linen and silk pill less than most. The primary drivers of pilling are the physical characteristics of the textile (including both the initial fibre, and the way in which it is processed during manufacturing), the personal habits of the textile's wearer, and the environment in which the textile is used. Fibers such as wool, cotton, polyester, nylon and acrylic have a tendency to pill the most, but wool pilling diminishes over time as non-tenacious wool fibers work themselves free of the fabric and break away, whereas pilling of synthetic textiles is a more serious problem, because the stronger fibers hold on to the pills preventing them from falling off.

In general longer fibers pill less than short ones because there are fewer ends of fibers, and because it is harder for the longer fibers to work themselves out of the cloth. Fabrics with a large number of loose fibers have a higher tendency to pill. Also, knitted fabrics tend to pill more than woven fabrics, because of the greater distance between yarn crossings in knitted fabrics than in woven ones. For the same reason, a tightly knitted object will pill less than a loosely knitted one. When a fabric is made of a blend of fibers where one fibre is significantly stronger than the other, pills tend to form as the weaker fibre wears and breaks, and the stronger fibre holds the pills onto the cloth.

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