Patent ID: 8043706

Claim:
An inorganic composition article containing a Li 2 O component and an Al 2 O 3 component in terms of oxides with a mass ratio of Li 2 O to Al 2 O 3 , Li 2 O/Al 2 O 3 , being no less than 0.3 wherein SiO 7 is contained in 66.7 to 90%, the Li 2 O component is no less than 7.0%, a MgO component is contained in 0.8% to 3%, and a K 2 O component is contained in 1.0 to 3% by mass in terms of oxides, containing crystals, having a mean linear expansion coefficient of no more than +120 (×10 −7 C −1 ) in the temperature range of 25 to 100° C. and a surface being provided with a compressive stress layer.