Preparation and optimization of Si3N4 ceramic slurry for low-cost LCD mask stereolithography

Abstract Mask stereolithography provides a new way to manufacture various high-performance engineering ceramics. However, the specialized commercial ceramic stereolithography equipment and materials are too expensive for ordinary researchers and consumers. The problem of lacking low-cost ceramic stereolithography technology needs to be solved. Due to the low intrinsic surface charge, high refractive index and high light absorption of silicon nitride ceramic, its light curable slurry with high solid content, low viscosity and low sedimentation still needs further study. In this investigation, a 40 vol% silicon nitride ceramic slurry suitable for liquid crystal display (LCD) mask stereolithography was developed. Through the experimental analysis of the slurry performance, 20 wt% of low shrinkage monomer ACMO, 30 wt% of non-reactive solvent POE and 50 wt% HDDA were optimized as the liquid phase of the silicon nitride slurry. A mixed dispersant of KD1 and CC42 was chosen to control the slurry viscosity and sedimentation. The curing thickness was increased to 38 μm under 56.8 mJ/cm2 exposure. The application of low-cost LCD based mask stereolithography in silicon nitride printing may play a role in the research and application of ceramic mask stereolithography.