Novel active electrodes for ECG monitoring on woven textiles fabricated by screen and stencil printing

This paper describes a process for fabricating active electrodes and flexible conductive tracks on woven textiles for use in electrocardiogram (ECG) monitoring systems. The process involves the screen and stencil printing of dielectric and conductive polymer pastes on to a textile substrate. Unlike previous printed active electrodes which are printed on non-woven textiles, this paper reports active electrodes which are printed on to a significantly more challenging woven textile by making use of a polymer interface paste that reduces the surface roughness of the underlying textile. The conductive paths supplying power to the electrodes and carrying the buffered signal to the amplifier are implemented with a screen printable silver polymer paste. The electrode material is a stencil printed carbon loaded rubber. The buffer amplifier, which converts high impedance signals into low impedance signals, is integrated into the electrode structure, reducing the area taken up by the components and improving comfort during wearing. These electrodes are compared to passive electrodes fabricated with the same process and also to commercially available Ag/AgCl electrodes in an ECG monitoring application when the monitored subject is stationary, walking and jogging. It is shown that the textile active electrodes provide significantly improved performance compared to textile passive electrodes and similar performance to the Ag/AgCl electrodes.