The nominating institution Bundesministerium für Bildung und Forschung on the breakthrough:

Dr. Rapp pushed boundaries in glass production since he is able to print glass. This disruptive innovation in glass processing has more than one astonishing advantage, such as low production cost, scales up to mass manufacturing with existing machines and most limitless freedom of design. Liquid glass is the main ingredient of his Innovation. It is a plastic fluid full of tiny glass that solidifies when exposed to light. The liquid works with standard 3D printers to create any structure.