Robust and Multifunctional Conductive Yarns for Biomedical Textile Computing

Abstract

Performance and durability of conductive yarns are essential factors to consider in the development of smart garments for textile computing applications. Conductive yarns and materials are used in various consumer and industrial products, however, their performance after washing, which is present with smart garments, is an unconventional, yet important consideration. This study investigates the impact of domestic washing on conductive silver-plated nylon and carbon-containing nylon yarns knitted into different patterns, simulating the incorporation of the conductive yarns into smart textiles. Various factors such as conductive yarn materials, types of knitting machine, and conductive feature patterns were considered. The resistance of silver-based textile electrodes increased by 100−300% over 50 wash cycles. Sulfidation and mechanical abrasion are the two main reasons for silver yarn degradation. The resistance of carbon-based textile electrodes stabilized after about five laundry cycles, showing little to no change afterward. Finally, the best performing silver and carbon electrodes were compared with gold-standard hydrogel electrodes for skin-electrode impedance and electrocardiogram measurement before and after 35 times of laundering. The results obtained demonstrated that both of the textile electrodes performed comparably to hydrogel electrodes and can be considered for continuous monitoring of biopotential signals from the human body.

Textile Technology for Soft Robotic and Autonomous Garments

“…[ 61,69 ] EMG sensors help detect user intent and may include traditional adhesive electrodes that are not part of the wearable robot, [ 20,74 ] or can employ garment‐integrated textile electrodes. [ 75,76 ] Textile‐based strain and pressure sensors can determine assistive glove position and grasping force. [ 14,67 ] Recently, textile‐based strain sensors have been used to estimate the position of the shoulder, which is particularly complex due to its multi degree‐of‐freedom (DOF) motions.…”

“…In their study, EDS spectroscopy confirmed the presence of sulfur, indicating the silver yarns had undergone a reaction that produces a silver sulfide tarnish which occurs in the presence of sulfur and humidity. [ 76 ] For more on electronic fibers for textiles (and in addition to reviews mentioned in the sensing section), Lund and colleagues have prepared a review. [ 509 ]…”

Multichannel ECG recording from waist using textile sensors

“…In recent years, numerous studies have looked into the effects of electrode position, size, and skin contact pressure (holding pressure) on signal quality [21][22][23]. In addition, other factors such as electrode to skin sensorial comfort, integration or construction techniques, and laundering/reusability need to be considered in the design, development and selection of textile electrodes for long-term ECG monitoring [24,25]. Athos, Hexoskin, OMSignal and Hitoe are examples of textile-based electronic devices that can collect ECG signal from the torso.…”

Smart Textiles Testing: A Roadmap to Standardized Test Methods for Safety and Quality-Control

“…The researchers recommended using liquid detergents, free of any form of bleaching agents, for e-textiles. Recently, researchers from the University of Toronto and the University of Waterloo developed two different electrocardiogram (ECG) electrodes made of silver-coated and carbon-suffused nylon yarns [48]. Although silver-coated ECG electrodes resisted well up to 35 washes, the carbon yarns yielded a longer lifespan and maintained a reasonable signal quality for the ECG biosignals.…”