High-Efficiency High-Resolution Multimaterial Fabrication for Digital Light Processing-Based Three-Dimensional Printing

We developed and constructed a novel digital light processing-based microstereolithography three-dimensional printing system capable of producing high-resolution components made of multiple materials in a fully automated, efficient, layer-by-layer manner. A high-contrast digital micro display with a pixel size of 15 μm was used to project customized 405 nm images through a borosilicate glass plate coated with optically clear polytetrafluoroethylene to induce polymerization in a variety of acrylate-based photocurable polymeric resins, where each layer contained multiple resin types. The new minimal-waste material exchange mechanism involves an air jet to remove residual liquid resin attached to the substrate after each exposure, which eliminated the need to use cleaning solutions that have been known to damage printed features. Complex, multimaterial microlattice structures were printed about 58% faster than existing studies that used cleaning solutions. Mechanical tests of tensile specimens demonstrated that the printing process formed sufficiently strong bonds between differing materials. The multimaterial capabilities of the new system, demonstrated as proof-of-concept in this article using photocurable polymer varieties, open doors for potential high-resolution high-efficiency multimaterial fabrication of a broad range of microarchitectures with novel functionalities and optimized performance made of ceramic, metallic, and biomaterials that find applications in the fields of metamaterials, bioinspired soft robotics, biodevices, microelectromechanical systems, optics, and microfluidics. System optimization to facilitate such capabilities remains as motives for complementary studies.