Influence of dispersant concentration toward enhancing printing precision and surface quality of vat photopolymerization 3D printed ceramics

The primary objective of this study is to develop an optimal dispersant concentration for high-precision PZT ceramic components with a high surface quality via a digital light processing (DLP) based vat photo polymerization method. Here, the ceramic suspension formulations composed of PZT ceramics (80 wt%), photoinitiator (1 wt%), dispersant (1,2,3 wt%), and monomer (18,17,16 wt%) were prepared to characterize the influences of dispersant concentrations on 1) the rheological properties and 2) the dispersion stability of ceramic suspensions as well as 3) the curing properties and 4) the surface quality of the DLP printed ceramic components. Interestingly, the optimal dispersant concentration (2 wt%) determined by FTIR spectroscopy induced the lowest viscosity, the lowest sedimentation rate, and the highest dispersion stability, which are considered desirable for the DLP printing process. Furthermore, 2 wt% dispersant significantly improved not only the printing precision by 43% but also the surface quality by 56% compared to the results obtained from the non-optimal dispersant concentration. This work proposes a novel perspective that the dispersant concentration affects the rheological properties as well as the printing results such as the printing precision and surface quality, which can contribute to the advancement of vat photopolymerization based ceramic 3D printing technology.