Fabrication of Silver Electrical Circuits on Textile Substrates by Reactive Inkjet Printing

Delivery of electronic functionality such as sense and response to the human body using smart textiles is important for developing wearable electronics. As the key component of connecting various devices in smart textiles, electrical circuit with excellent electrical performance is an essential effort for ongoing research in textronics. In this work, a new liquid phase chemical reduction method combined with inkjet printing technology for fabricating electrical circuits on textile substrates is adopted. The aqueous silver nitrate is ejected spot by spot onto textiles that are wetted with ascorbic acid solution and placed on the copper foil. After redox and replacement reactions, silver particles are deposited to form conductive layer for electrical circuits. Deposited layers of silver with high conductivity up to 0.86201 x 10(6) S/m and the sheet resistance in the range 0.0116-0.06913 Omega/sq. Based on these findings, we realized the textile capacitive sensor with good response time, and stability for 1500 cycles of repeated loading. The fabricated textile electrocardiogram (ECG) electrode attached to braces could be effective for human heart rate and ECG signal monitoring.