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Nylon is the title of polyamide fiber in China. The origin of this title is that Jinzhou, China was the first to produce this type of composite fiber. This fiber system was created by the American DuPont company Carlisle in 1938 and named Nylon, now transliterated as nylon. It is widely used in industry and civilian applications.

Spandex is a constituent fiber with high elongation at break (over 400%), low modulus, and high elastic recovery rate. Spandex is generally not used alone, but is added in small amounts to the fabric. This type of fiber has both rubber and fiber functions.

Someone asked about thermal underwear, which contains 60% cotton, 35% nylon, and 5% spandex. It is unknown whether wearing nylon and spandex close to the body will be harmful to the human body, and whether it can be worn when sleeping at night. Actually, there are almost no cotton fabrics nowadays, and cotton is not wear-resistant. If you are allergic to these materials, you can still check the water washing label when choosing underwear, and try to choose underwear with a higher cotton content.

Article source: Nylon colored yarn

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