Continuous forming of ultrathin glass by float process

Abstract In this paper we report a novel development in forming ultrathin glasses by float process. The design principal and theoretical consideration for the tin bath, which is the heart for the process, are presented in relation to the ultrathin glass forming. Continuous stretching of glass to 0.12 mm on the top of molten tin is essentially a process of accurately controlling and maintaining a dynamic equilibrium of a large‐scale open system where not only thermal energy is exchanged but also the mass is in a constant moving state. Due to this complicated nature, despite many computer simulation attempts, no one has come up with a physical model that can reasonably depict stretching process on molten tin. Through pilot plant experiments, we have established essential technical parameters for continuous stretching of 0.12 mm glass including distributions of temperature/viscosity, glass ribbon traveling speed, and thickness along the longitudinal direction of the tin bath. The action and settings of edge rollers that allow smooth stretching of the glass ribbon to take place are described and discussed. We believe that this novel development not only attracts interests of materials researchers, but also contributes substantially to the knowledge reservoir of glass science and technology.