Reinforcing glass plate

The present invention has a thermal expansion coefficient is small and the surface compressive stress due to physical reinforcement is high, to provide a reinforcing glass plate tempered glass excellent in low density and abrasion resistance is possible. Hereinafter has a composition consisting by weight percent, reinforced glass plate which is characterized in that it possible to enhance processing by heating and quenching. SiO B MgO 0.1~12%, CaO 0.1~12%, Na MgO + CaO + SrO + ZnO 3~16%, Al