Preparation of Conductive Screen-Printing Ink for High-Performance Bendable and Wearable ECG Electrodes on Fabric Substrates

Abstract

Monitoring of vital signs is a necessary tool to diagnose the symptoms of illness. This work developed screen-printing inks for conductive nanomaterials to fabricate electrocardiogram (ECG)-compatible fabric electrodes. The contents of the polymer matrix, calcium carbonate additive filler, and conductive nanomaterials (silver nanoparticles and copper nanowires) on the resistivity of the composite inks were optimized. A facile process of screen printing was applied to fabricate the electrodes on fabric to create an efficient conductor with high stability in conduction. The fabricated electrodes exhibited flexible and bendable behavior over 0.7% bending strain for wearable components. The results showed that the fabricated electrode based on copper nanowires resistivity was 40.01 ± 1.94 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{k}\Omega $ </tex-math></inline-formula> /cm, and the proposed signal-to-noise ratio (SNR) was approximately 27.16 ± 9.37 dB. Therefore, these fabricated electrodes can be applied in wearable vital biosignal detection devices that perform with high sensitivity during movement, thereby providing health monitoring opportunities. Moreover, the fabricated electrodes can be used without excessive pressure or an electrolyte gel layer, thus overcoming the challenges of developing a portable device.