Patent ID: 8840997

Claim:
A cover glass comprising a compressive-stress layer on principal surfaces thereof, the cover glass having a glass composition containing 50% to 70% by mole of SiO 2 , 3% to 20% by mole of Al 2 O 3 , 5% to 25% by mole of Na 2 O, more than 0% by mole and less than or equal to 2.5% by mole of Li 2 O, 0% to 5.5% by mole of K 2 O, 0% to less than 3% by mole of B 2 O 3 , and more than or equal to 0.11% by mole of MgO/(Li 2 O+Na 2 O+K 2 O), wherein the glass composition does not substantially contain As 2 O 3 and Sb 2 O 3 .