Direct screen printing of single-faced conductive cotton fabrics for strain sensing, electrical heating and color changing

A simple but effective method of developing multifunctional wearable cotton fabrics was achieved via screen printing of carbon nanotube (CNT) ink on one side of a weft knitted cotton fabrics. Scanning electron microscopy was employed to investigate the morphology of the CNT/Cotton Composite fabric (CCCF). The deposition of conductive CNT paste has brought electric conductivity (50.75 Ω/sq) to CCCF. The electromechanical performance of the CCCF was evaluated, and the CCCF showed great stability and flexibility in terms of strain sensing. The CCCF was demonstrated to sense different human activities such as speaking, drinking, writing, and bending of finger and wrist. The developed CCCF also exhibited excellent electrothermal performance with the potential to be used as an electric heater. Color changing performance was generated by screen printing thermochromic inks on the back side of CCCF. The flexible strain sensors, electric heaters, and color-changing textiles made from CCCF are promising candidates as smart textiles to be used as wearable electronic devices, cold weather conditioners, and smart displays.