Graphical AbstractVerifiedHeat-Shrinkable Thermoplastic Films Enable Universal Conformal Electronics via Semi-Liquid Metal Circuits
Conformal electronics that seamlessly adhere to three-dimensional (3D) surfaces are critical for wearable devices, bio-integrated sensing, and human-machine interfaces. However, existing methods—such as in-situ printing on curved surfaces or planar fabrication followed by lamination—struggle with high costs, complex motion control, or poor adhesion on irregular geometries. Here, we highlight a recent breakthrough by Jiang et al. (Nature Electronics, 2026) that employs heat-shrinkable thermoplastic films to achieve precise conformal mapping of electronic circuits onto arbitrary 3D surfaces. The method involves printing a semi-liquid-metal composite ink—comprising silver-coated copper particles dispersed in eutectic gallium-indium alloy (EGaIn)—onto pre-stretched polyvinyl chloride (PVC) films. Upon heating to approximately 70 °C, the film shrinks, generating compressive strain that drapes the circuit onto the target substrate. The composite ink maintains metal-level conductivity (9.5×10^6 S m^-1) and exhibits roughly doubled viscosity relative to neat EGaIn, preventing fracture and agglomeration during shrinkage. A poly(methyl methacrylate) (PMA) interfacial layer ensures stable adhesion. Finite element simulation enables pre-deformation pattern design, accurately predicting post-shrinkage layouts. The process is rapid (~5 s) and simple, successfully conforming to diverse surfaces including ceramics, metals, fruit peels, polytetrafluoroethylene (PTFE), and wet wood, with minimal resistance change. This strategy departs from reliance on intrinsic material stretchability, offering a cost-effective, universal route for conformal electronics with broad application potential in healthcare, environmental sensing, and intelligent interaction.
