Inkjet-printing deposition of silver electro-conductive layers on textile substrates at low sintering temperature by using an aqueous silver ions-containing ink for textronic applications

• Reactive silver ink for the inkjet printing of textile substrates was applied.
• Silver electro-conductive layers on textile substrates were fabricated.
• Silver printed layers were sintered at low temperature not exceeding 90 °C.
• Printed conductive layers showed a good adhesion and low surface resistances.
• Examples of textile sensors, actuators and electronics elements were realized.

The main problem in preparing stable and printable inks for the inkjet printing of textile substrates is in overcoming their roughness and high sintering temperature. In this study, the modified Tollens’ process for the preparation of a suitable water-soluble ink containing silver for the inkjet printing of textile substrates as a tool for textronic applications was adopted. The choice of this type of ink ensured inkjet printability of textile surfaces with simultaneous sintering at low temperature not exceeding 90 °C. The surface resistance of the inkjet-printed silver layers on all the textile fabrics studied steadily decreased with the number of silver layers deposited. In the case of 8 prints on synthetic textiles made of polyacrylonitrile, polypropylene, polyester and basalt fibres the surface resistance in the range 0.155–0.235 Ω/sq. was achieved. For some textile substrates made of natural fibres and their blends with synthetic fibres, to achieve the proper conductivity an interlayer of acrylic copolymer containing resin was applied. The surface resistance for the same number of prints was in the range of 0.389–0.622 Ω/sq. The study confirmed the usefulness of ink applied in printing silver electrodes and their resistance to bending, washing and dry-cleaning processes. On the basis of these findings, some potential applications in textronic systems, e.g., capacitors, textile heating actuators, textile patch antennas, and high-frequency transmission lines were proposed.