Polyester is also called high-strength thread, nylon sewing thread is called nylon thread, we usually call it (pearlescent) polyester sewing thread is made of polyester long fiber or short fiber, wear resistance, low shrinkage, good chemical stability. However, the melting point is low, high-speed and easy to melt, clog the eye of the needle, easy to break the thread, polyester thread is widely used in the sewing of cotton fabrics, chemical fibers and blended fabrics because of its high strength, good wear resistance, low shrinkage, good moisture absorption and heat resistance, corrosion resistance, not easy to mildew, and no moth-eaten fabrics. In addition, it also has the characteristics of complete color, good color fastness, no fading, no discoloration, and sun resistance. The difference between polyester sewing thread and nylon sewing thread, polyester is lit up in a lump, emitting black smoke, the smell is not heavy, there is no elasticity, and the sewing thread of nylon is lit up in a lump, emitting white smoke, and pulling up has a strong elastic smell. High abrasion resistance, good light resistance, mildew resistance, coloring about 100 degrees, low temperature dyeing. It is widely used because of its high seam strength, durability, flat seam edge, and ability to meet the needs of a wide range of sewing industry products.