The development of a highly stretchable, durable, and printable textile electrode

Abstract

In textile and wearable electronics, the demand for a stretchable, durable, and easily manufacturable electrode is ever increasing. This paper describes the development of a highly stretchable and durable textile electrode fabricated by simple stencil and screen printing methods. It specifically investigated the effects of an interface layer as a planarization layer between the conductive electrode and the textile on the durability of the textile electrode. A stretchable conductive paste was synthesized by mixing Ag flake powder in polyester. The conductive electrode was encapsulated with Ecoflex material. The stretchability and durability of the textile electrodes were evaluated via stretching, bending, Massachusetts Institute of Technology (MIT) folding, twisting, and dynamic endurance tests. The stretching and MIT folding tests indicated that the interface layer significantly enhanced the durability of the textile electrode. A highly stretchable and flexible textile electrode exhibited a low sheet resistance of 0.05 Ω/square, excellent stretchability of 70%, and a critical bending radius of 1.5 mm. The textile electrodes also withstood dynamic stretching and bending endurance tests of 10,000 cycles. The illumination of a light-emitting diode with the conductive electrode was also stable under 70% tensile strain and in water. The potential application of the textile electrode as a strain sensor was demonstrated by applying it to a glove to detect finger motion. The strain sensors responded well to the finger motion, with considerable stability and repeatability.

Nanomaterials-patterned flexible electrodes for wearable health monitoring: a review

“…The fifth challenge of the printed textile electrode is durability [ 358 , 359 ]. The reported mechanical stability of printed textile electrodes is limited to a few thousand bending cycles, which in turn limits the possibility of long-term usage of the sensors.…”

Towards the Functional Ageing of Electrically Conductive and Sensing Textiles: A Review

“…A conductive silver ink was printed on PU-coated cotton fabrics and encapsulated. The treatment with the MIT folding endurance tester showed a clear ageing advantage for the encapsulated samples [ 108 ].…”

Approaches for Solution-Processed Encapsulation of Printed Medical Wearable Devices

“…Some solutionprocessed encapsulation examples are listed in Table 1. Materials that are compatible with solution-processed encapsulation are fluid inks or pastes such as Ecoflex, SU-8, formulated polymer solutions (PDMS, PI, PVC, etc), dielectric paste [6,12,25,26,[30][31][32][33][34][35][36]. Ecoflex is a printable bioplastic with special properties such as flexibility, toughness and water resistance [37].…”

“…Kim et al fabricated a wearable screen printed salivary uric acid mouthguard biosensor and the DuPont 5036 dielectric paste was screen printed on the sensor to confine the electrode areas [6]. In [25], the Ecoflex encapsulation layer was screen printed on the textile strain sensor, which can be used on a glove to detect the finger motion. The strain sensor consists of interface layer, conductive layer and encapsulation layer.…”