Brush-painting and photonical sintering of copper and silver inks on cotton fabric to form antennas for wearable ultra-high-frequency radio-frequency identification tags

Additive deposition of inks with metallic inclusions provides compelling means to embed electronics into clothing in a seamless way. We present a simple single-step brush-painting method for depositing copper and silver inks directly on ordinary cotton fabric and discuss the optimization of the photonical sintering of both materials. For the first time, we demonstrate the deposition and sintering of copper oxide ink on fabric achieving high electrical conductivity suitable for radio-frequency electronics. The results from wireless testing confirmed that the radio-frequency identification tags based on the copper and silver ink antennas were readable from 6 and 10 m, respectively.