Direct-ink-writing of highly deformable, multi-layered electrical devices using elastomer-based dual inks

The advancement of soft electronics has enabled the creation of highly deformable, multi-functional devices capable of conforming to various surfaces. However, achieving both high deformability and electrical stability suitable for target applications remains a critical challenge. In this study, we present a direct-ink-writing (DIW) approach utilising dual-functional inks to fabricate highly deformable, multi-layered electronic devices. A styrene-ethylene-butylene-styrene (SEBS) elastomer ink ensures mechanical flexibility, while a SEBS-silver (SEBS-Ag) composite ink provides electrical conductivity. The printed conductive structures exhibit conductivities of approximately 3.37 × 105 S·m−1, and the total conductance increases linearly as the number of printed layers increases. The DIW approach enables precise layer-by-layer deposition, facilitating the fabrication of integrated components such as substrates, insulation layers, interconnects, vias, and electrodes. Furthermore, the 3D-printed serpentine-shaped device, with an 800-µm thickness, exhibits conformal contact with curved surfaces and maintains electrical functionality even under extreme deformations. The combination of material and structural innovations demonstrates the potential of 3D-printed electronics for next-generation soft electronics. This study highlights the potential of our DIW strategy for developing multifunctional, highly deformable, and mechanically robust electronic systems, paving the way for next-generation wearable and adaptive electronics.