THERMALLY TEMPERED GLASS BY AIR JET AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide a production process for thermally tempered glass products that can completely avoid the natural damage of thermally tempered glass caused by foreign substances including nickel sulfide. SOLUTION: In the annealing step continuously following the glass-enhancing step where the glass is heated and then cooled down by wind, the thermally tempered and nickel sulfide-containing glass that has thermally residual stress and extends the cracks caused by the stress is held at a prescribed temperature for a prescribed time whereby glass is continuously transferred from theα-phase that is stable at elevated temperature to theβ-phase that is stable at lower temperature to break the nickel sulfide-containing glass by the volume expansion of the foreign substance and remove therefrom.