Mitigating the Impact of Thermoplastic Polyurethane Films on the Performance of Electronic Textiles

Abstract

When printing electronics onto textiles, a thermoplastic polyurethane (TPU) layer is typically used, which unfortunately interferes with many desirable properties of textiles. To minimize this impact of the TPU, the effect of different TPU types and lamination conditions on the electronic textile properties are investigated. It is found that for optimal conductivity, the TPU film thickness should be ~ 100 µm, but thicker films should be avoided as they increase stiffness and worsen breathability. Less dense (less crystalline) TPU is found to be preferable. There is trade-off with some lamination parameters, with higher temperatures and longer times increasing stiffness but improving printed ink conductivity; however, a lower lamination pressure is preferable in either case.