Direct writing of colloidal suspensions onto inclined surfaces: Optimizing dispense volume for homogeneous structures

A process to fabricate structures on inclined substrates has the potential yield novel applications for colloidal-based structures. However, conventional techniques, besides coffee ring effect (CRE), anisotropic particle deposition along inclination direction (IE) is expected occur. We hypothesize that both effects can be inhibited by reducing dispense volume during printing direct writing. combined an additive manufacturing technique, namely writing, with colloidal assembly (AMCA) automated and localized drop-cast of polystyrene silica suspensions onto surfaces. Herein, we investigated influence substrate tilting angle colloids resulting structures’ morphology. The results demonstrate a reduction in hinders CRE IE particles’ systems, even though evaporation mode different. For polystyrene, droplets evaporated solely stick-mode, enabling “surface capturing effect”, while silica, mixed stick–slip “confinement effect” was observed, which improved uniformity deposition. These findings were used generate model critical droplet radius needed print homogeneous substrates.