Enhancing precision in ceramic vat photopolymerization 3D printing through dispersant optimization

Dispersant is critical in the ceramic vat photopolymerization (VP) due to its decisive impact on ceramic particle dispersion and suspension stability. However, the mechanisms by which dispersants influence photopolymerization of suspension remain underexplored. In this paper, the effects of the dispersants' refractive index and absorption coefficient on the light intensity distribution within suspension was investigated using a finite element method (FEM) simulation. The results indicate that the absorption coefficient is the primary influencing factor; as the absorption coefficient increases, the light transmittance of the suspension significantly decreases. Additionally, the photopolymerization performances of Al2O3 ceramic suspensions formulated with different dispersants were investigated. We found the mechanisms by which dispersants influence photopolymerization behavior: by affecting light absorption through absorption coefficient and by directly impacting the polymerization reaction through functional groups. The study successfully achieved VP 3D printing of high-precision ceramic architectures with micron-sized features via dispersant optimization. This paper provided a new insight into optimizing fabricating resolution in ceramics VP 3D printing.