| a soda-lime-silica glass formed by rolling the hot glass into a plate that is subsequently ground and polished, used in large windows, mirrors, etc. |
| plate glass n. A strong rolled and polished glass containing few impurities, used for mirrors and large windows. |
plate glass
form of glass originally made by casting and rolling and characterized by its excellent surface produced by grinding and polishing. Plate glass was first made in the 17th century in France, after which several improvements in the original batch technique culminated in the Bicheroux process (1918), in which the glass was received by power-driven rollers that then delivered it in thinner sheets of greater length to be sheared into sections and annealed (heated, then cooled, to make it less brittle). A continuous process was then developed in which the glass passed through the annealing stage before being cut into lengths, ground, and polished.
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