Through the thermal tempering process, the bending strength of the glass is increased and if the load is too high, the glass decays into small blunted crumbs. Therefore the risk of injury is significantly reduced, so it can also be considered as tempered safety glass (ESG).

The thermal hardening of the glasses takes place after their processing. Therefore all processing operations must be made before the finishing process, such as cutting to the final dimension, edge processing or drilling.

The production of thermally hardened glass takes place in a furnace which heats the glass to about 600°, then the glass is cooled down in a certain cooling curve.This results a compressive stress in the glass surface.

Thermally hardened glasses offer the following properties:

• high impact resistance
• high scratch resistance
• high thermal shock resistance
• high bending strength
• crumbling in breakage