The previous article mentioned the natural characteristics that make cotton popular for a long time. We also mentioned that in order to make cotton more perfect for using in clothing, humans have created many different types of cotton materials, the most widely known of which is probably "Cotton Lycra"! (Review the previous article: "A long lasting classic underwear fabirc-Cotton" https://en.under-stand.jp/blogs/news/20190726understand) Lycra is an elastic fiber invented by DuPont in 1959. They registered Lycra to be the brand name, and its real scientific name is Spandex, also called Elastane in Europe. People who don't know will think that this is three different fibers, but...