Sewing Threads

Abstract

Sewing thread is a vital element in textile products for connecting parts, providing stability, preventing fabric ends from fraying, embellishing, and many other applications. The modern sewing process on industrial sewing and embroidery machines imposes great demands on sewing thread. In lockstitch machines, for example, a sewing thread passes up to 80 times (depending on stitch density) through the eye of the needle before forming a stitch. In addition, there is a jerky stress when accelerating and stopping the sewing machine. Sewing threads consist of fibres and/or filaments, which are processed into yarn, then plied and twisted into a thread. The thread is dyed, lubricated, a special finish is applied if necessary, and is made up on spools. Depending on the required function of the finished good, sewing threads require different properties. These are determined by raw material, construction (construction type, twist, ply and cord) as well as linear density (numbering) and special finishes (water repellent, bonded, etc.). A look at the quality features of sewing threads (strength, elasticity, gliding performance, thread consistency, lubrication, twist purity, etc.) shows their importance in the sewing machine processes. Chapter 7 presents these aspects of sewing and embroidery threads, mainly based on FOCUS – the compendium of threads by the AMANN Group.