Non-Sticky Display Eliminates Surface Roughness and Interface Adhesion: Enabling Large-Scale LCD-Based 3D Printing

Among all polymer-based 3D printing technologies, liquid crystal display (LCD)-based vat photopolymerization (VPP) has emerged as a promising method, offering high resolution and cost-effectiveness through large-area LCD panels. However, its adoption is hindered by two key challenges: surface roughness caused by the LCD's black matrix and interface adhesion with the LCD panel. This study introduces a non-sticky display (NSD) approach using sub-micron structured polydimethylsiloxane (PDMS) film laminated onto the LCD panel to address both issues simultaneously. The optimized NSD 2000 configuration achieves an 82.5% reduction in surface roughness while preserving print resolution through controlled light diffusion. Its sub-micron structured surface creates a stable Cassie state by trapping air, imparting hydrophobic properties and low work of adhesion. Additionally, the PDMS layer eliminates electrostatic adhesion between oppositely charged surfaces, such as Teflon (interface) and the LCD panel, effectively resolving the interface adhesion issue. This reduces separation energy by up to 52% for high-viscosity foam resin and an 8-fold reduction of separation force for acrylate-based fast-curing resin. The successful printing of large-scale, complex geometries with challenging materials and the improved mechanical and optical properties of the printed parts demonstrate the NSD approach's potential for advancing LCD VPP to develop functional parts.