Fabrication of low cost and scalable carbon-based conductive ink for E-textile applications

Abstract

In this work, we demonstrate a simple, highly scalable and cost-effective fabrication process of functional carbon black (CB) ink from burned charcoal of dry woods. Our process consists of both dry and wet medium blending of burned charcoals which reduces the consumption of high processing time and uses of sophisticated instruments to manufacture functional CB. The process includes formulation of functional CB ink prepared with poly-vinyl alcohol (PVA) binder, which is applied to the textile fabric using a simple pad-dry process. The sheet resistance and the loading percentage of carbon ink on the cotton fabric are saturated to ∼(25–28) kΩ/sq. and ∼(115–130) wt.% of the native fabric, respectively after 7 repeated padding cycles. The carbon-coated fabrics are demonstrated durable and reliable with repeated bending cycles. Although the resistance of the conductive fabric increases after the first wash cycle, interestingly, the resistance of the fabric tends to decrease in the following 11 consecutive wash cycles. The coated conductive fabrics are used as bend-sensors since it is able to detect very low bending angle for at least 1000 repeated bending cycles. Additionally, we demonstrate the use of carbon coated cotton fabric as heat-spreading materials of a textile heater.