Hybrid Multimaterial 3D Printing Using Photocuring-While-Dispensing.

Three-dimensional (3D) printing methods, such as vat photopolymerization (VPP) and direct-ink-writing (DIW) processes, are known for their high-resolution and multimaterial capabilities, respectively. Here a novel hybrid 3D printing technique that combines the strengths of VPP and DIW processes to achieve multimaterial and high-resolution printing of functional structures and devices, is presented. The method involves dispensing liquid-like materials via syringes into a photocurable matrix material and subsequently using a Galvano mirror-controlled laser beam to selectively photocure the dispensed material trace or the matrix material surrounding the trace. The laser beam scanning and syringe dispensing are synchronized with a set delay to control liquid diffusion and in situ fixture. The versatility of the method is demonstrated by fabricating intricate 3D ant and wheel prototypes using various materials available for VPP and DIW technologies. The proposed photocuring-while-dispensing strategy offers advantages over conventional multimaterial 3D printing methods, such as integrating materials regardless of photocurability and viscosity, and fabricating heterogeneous structures with complex geometries and high resolution. With its principle demonstrated, this multimaterial 3D printing process will open up a wide range of potential applications with diverse functionalities and materials.