Analysis of the principle of yellowing of spandex fabric

Spandex is a fiber commonly used in our lives. The most prominent feature is good elasticity, and it has the advantages of low denier, large elastic modulus (elongation at break up to 400%-800%) and small specific gravity. Spandex is a commonly used fiber in our lives. The most prominent feature is good elasticity, and it has the advantages of low denier, large elastic modulus (elongation at break up to 400%-800%), and small specific gravity. Spandex can be blended with wool, cotton, polyester, acrylic, viscose and other textile fibers. The fabric made is soft, elastic and comfortable to wear. It is widely used in fitness clothes, swimwear, jeans, tights, underwear, and one-piece Among clothing and intimate underwear, because women have higher requirements for close-fitting, spandex fabrics are more popular among women. Since the spandex molecular chain contains a large number of reactive groups such as amino groups, it is easy to turn yellow during high-temperature setting or storage, which affects the quality of finished products, especially fluorescent whitening fabrics and light-colored fabrics. In order to improve the spinning performance of spandex, silicone oil lubricants and other additives are used in the weaving process. These additives will naturally degrade over time and cause the fiber to turn yellow. In addition, spandex itself is not easy to color, that is, conventional dyes cannot make spandex color. Therefore, after the fabric is dyed, the so-called yellowing phenomenon will also occur if the reduction and cleaning are not sufficient. The best-selling black spandex filament---solution coloring technology: black spandex is a widely used variety in clothing fabrics. In recent years, the domestic black spandex filament production capacity has been continuously expanded and the product performance has been continuously improved. The black spandex filament spun directly through special processes such as dope coloring or online addition, not only has a more uniform and long-lasting black effect, higher color fastness and excellent washing resistance, but also eliminates the dyeing process of the fiber and reduces Energy consumption in the dyeing process reduces environmental pollution.