Textile‐Based Capacitive Pressure Sensors Enabled by Ultrasonic Spray‐Coated Carbon Black Electrodes and Electrostatic Flocking

Abstract

Textile‐based pressure sensors are essential for wearable electronics, but achieving mechanical robustness, high sensing performance, and scalable fabrication remains challenging. A fully textile‐integrated capacitive pressure sensor is developed using low‐cost materials, comprising ultrasonic spray‐coated carbon black (CB) electrodes and electrostatically flocked nylon microfiber dielectric layers on Kevlar substrates. A statistically guided optimization approach, combining Taguchi analysis and response surface methodology, establishes the relationship between deposition parameters and conductive network formation, producing uniform coatings with a sheet resistance of approximately 50 Ω sq−1. The vertically aligned nylon microfibers form a compressible air–fiber dielectric structure that enhances capacitance changes under pressure. The sensor exhibits a sensitivity of 1.05 kPa−1 at low pressure (< 1.5 kPa), low hysteresis (10.1%), and stable performance over 1000 loading cycles. Fabrication is achieved without lithography, elastomers, or nanomaterial ink, providing a simple, scalable, and cost‐effective textile‐only sensing platform. A 3 × 3 sensor array demonstrates spatial pressure‐mapping capability, highlighting potential applications in ergonomic seating, smart safety garments, and the monitoring of ballistic or blast exposure events where puncture resistance is essential.