Liquid Glass: Polymerizable Silica Precursors for Microstructured Silica Glass Manufacturing: A Review

ABSTRACT “Liquid glass”, a silica‐based precursor processable via photo‐ or thermally induced curing, has emerged as a key platform for the fabrication of microscale silica glass structures. In contrast to conventional silica processing, which requires high‐temperature melting or harsh chemical treatments, liquid glass allows direct shaping under mild conditions, followed by conversion into dense inorganic glass through controlled thermal treatment. This capability opens a new route for the additive manufacturing of glass components with micro‐ to nanoscale dimensions. This review provides a detailed classification of liquid glass materials. Their polymerization and glass‐conversion mechanisms, including photopolymerization, condensation, and thermally induced network conversion, are systematically discussed. Key processing characteristics—such as achievable resolution, volumetric shrinkage, densification behavior, and compatibility with complex architectures—are compared and analyzed. Recent advances in micro‐optics, optoelectronics, microfluidics, security devices, protective structures, and mechanical applications are highlighted. Finally, remaining challenges in material design, processing efficiency, and functional integration are outlined, together with emerging opportunities in intelligent manufacturing, 4D printing, and adaptive or self‐healing glass systems.