Fremgangsmåte ved fremstilling av plane eller buede glassplater

摘要

Glass plates are thermally or chemically tempered to increase flexural bending strength. The tempered plates are subsequently subjected to a heat treatment in order to lower the possibility of spontaneous breakage of the glass plates. According to the method according to the invention the glass plates are tempered at least twice and again heat-treated. At least the second heat treatment takes place at higher temperatures than were used previously. The treated glass plates have increased flexural bending strength and reduced tendency to spontaneous breakage.