The Influence of Washing Cycles on the Conductive Threads Used in E-textiles

E-textiles and smart textiles have already reached a certain stage of development. Nowadays, smart textiles designed for medicine or sports have been developed to be worn directly on the body, just like conventional textiles. This is the reason, why e-textiles and smart textiles should be able to withstand mechanical and chemical stresses during washing cycles. It is therefore essential to focus on their durability through repeated wash cycles. This paper focuses on the effect of washing cycles on the conductive fibers used in E-textiles. Two commercial conductive threads (Madeira HC12, SilverTech + 100) and two hybrid threads (T1, T2) were developed at the Faculty of electrical engineering at the University of West Bohemia and were selected for the experiment. The threads T1and T2consist of silver-plated copper microwires plied with PES multifilament threads. The commercial threads are based on silver-plated polyamide filaments. These filaments have an order of magnitude lower resistance than hybrid filaments. This paper investigates the change in electrical resistance of the four above-mentioned embroidered conductive threads due to their exposure to 30 washing cycles. The results of this experiment are presented in the paper, which shows that the coated commercial threads show better results after 30 wash cycles but are not suitable for all applications compared to the hybrid threads because of their higher electrical resistance. The wash resistance of hybrid threads can be increased by isolating individual microwires, which is not possible with plated yarns.