Investigation of the Functional Ageing of Conductive Coated Fabrics under Simulated Washing Conditions.

Conductive textiles play an important role in recent electronics development; however, one of the major challenges remains their machine-washing durability. For the investigation of the basic wash ageing mechanisms, we used copper-plated polyamide 66 and cellulose fabrics and developed a wet and dry operable flex tester with online resistance recording. The evaluation was supported by abrasion tests, cyclic elongation tests and tribological investigation of dry and wet textile-textile friction. It was found that the contribution of mechanical and chemical ageing to wash ageing strongly depends on the substrate material. A bad adhesion of copper on polyamide 66 leads to early fatigue while better stability of the copper on cellulose leads to a stronger resistance against ageing. For both substrates, the delamination of the copper layer was the root cause of the fatigue, which is facilitated by the washing solution. Finally, a cumulative fatigue model was developed and the determination of the end of lifetime by the intended use is discussed.