1. There are also different brightness forms in the production of spandex, usually including:
(1) Transparent, CLEAR-LUSTER: The surface fiber is smoother, so the reflection becomes transparent, the friction rate is low, the uniformity of the strip is poor, and the color is also poor, which is suitable for the production of staple fiber materials, and is used more by fabrics.
(2) White root, DULL-LUSTER: that is, natural white, the surface fiber is uneven, the friction surface is large, the coloring effect is good, suitable for the production of long fibers, and the thick branch root is used, such as bust products and accessories.
(3) Translucent, BRIGHT-LUSTER: titanium dioxide and anti-slip agent are added inside, which has strong resistance to chemical agents, and swimsuits are used more because of their anti-chlorine function.
(4) Matte color, MATT-LUSTER: between natural white and translucent, matte white, suitable for knitting.
2. Spandex has different uses and various product forms, which are mainly divided into three types: bare yarn, core spun yarn, covered or twisted yarn. Each of these combinations corresponds to a different purpose.
(1) Bare yarn bare-yarn: 100% spandex yarn, bare yarn is generally not directly used on the fabric, most of them are produced together with opponent materials, and need to be produced by special devices. Knitwear is the most commonly used, such as swimsuits, sportswear, etc., generally 22-78Dtex.
(2) core-spun-yarn: yarn spun with bare yarn as the core and other materials as the outer skin, referred to as CSY. If cotton core spun is generally inserted into the drawn bare yarn on the spinning frame of the ring spinning machine, the elongation length of the bare yarn wrapped around the core spun yarn must be appropriately adjusted, and its expansion and contraction rate is suppressed at 2~3 times. Nowadays, core-spun yarn is divided into hard core yarn and soft-core yarn, and the opponent materials of core-spun yarn are cotton, polyester, nitrile and so on. It is widely used in fabrics, knitwear, bandages, socks, underwear, and denim, generally 22-235Dtex.