Washable heat-resistant and inkjet-printed devices on cotton fabric for wearable applications
Kyubin Bae, Bowoong Heo, Kyuhyun Hwang, Eunhwan Jo, Yunsung Kang, Soonjae Pyo, Jongbaeg Kim
Abstract
Electronic textiles (e-textiles) face challenges in maintaining fabric properties and achieving high electrical conductivity with screen printing and particle-based inkjet printing. While particle-free reactive inks enable high-resolution patterning with sufficient electrical conductivity, their application on cellulose-based fibers is hindered by negatively charged surfaces. This study introduces inkjet-printed e-textiles using reactive silver ink and carbon nanotube ink on poly-L-lysine-coated cotton fabric. Carbon nanotubes establish a conductive network that promotes silver ion reduction, yielding densely packed nanoparticles with enhanced conductivity (1.25 × 10⁵ S m⁻¹). The resulting composite functions as a resistive tactile sensor with high sensitivity (6.02 kPa⁻¹) due to the hierarchical structure of cotton fabric. In addition, the inherent heat resistance of cotton facilitates its high-temperature resistance during heating. In this work, the fabricated e-textiles maintain performance through bending, ironing, and washing, inferring our printing technique as a promising strategy for wearable devices. Developing electronic textiles which balance conductivity and high-resolution patterning is challenging due to the charged character of cellulose-based fibers. Here the authors report a silver-carbon nanotube ink which can be inkjet-printed onto poly-L-lysine coated cotton fabric for electronic textiles.