Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: A glass substrate includes, as a glass matrix composition as represented by mole percentage based on oxides, SiO2: 55%-75%, Al2O3: 2%-15%, MgO: 0%-10%, CaO: 0%-10%, SrO: 0%-10%, BaO: 0%-15%, ZrO2: 0%-5%, Na2O: 0%-20%, K2O: 5%-30%, and Li2O: 0%-5.0%. The glass substrate has a total content of alkali metal oxides, as represented by mole percentage based on oxides, of 10%-30%, a value obtained by dividing the total content of alkali metal oxides by the content of SiO2 of 0.50 or smaller, a value obtained by dividing the content of Na2O by a value obtained by subtracting the content of Al2O3 from a total content of Na2O and K2O of 0.90 or smaller, and an average coefficient of thermal expansion ?1 at 50° C.-350° C. of 11 ppm/° C.-16 ppm/° C.

Abstract: Provided is an optical glass suitable for an imaging lens or the like used for a vehicle-mounted camera exposed to harsh environment, having a high refractive index and high strength. The optical glass has a strengthened layer at a surface layer, and a depth of the strengthened layer is 1 ?m or more from a surface of the optical glass, and a refractive index (nd) of the optical glass is 1.73 to 2.10.

Abstract: Provided is an optical glass suitable for an imaging lens or the like used for a vehicle-mounted camera exposed to harsh environment, having a high refractive index and high strength, excellent crack resistance, and a sufficiently low glass transition point and devitrification temperature. In the optical glass, nd is 1.70 or more and 2.10 or less, Tg is 500° C. or more and 630° C. or less, the devitrification temperature is 1300° C. or less, a specific gravity is 4.0 g/cm3 or less, a crack initiation load (CIL) is 20 gf or more, and a fracture toughness value (Kc) is 0.60 MPa·m1/2 or more.

Abstract: A glass substrate contains, as a glass matrix composition as represented by mole percentage based on oxides, SiO2: 58-75%, Al2O3: 4.5-16%, B2O3: 0-6%, MgO: 0-6%, CaO: 0-6%, SrO: 5-20%, BaO: 5-20%, and MgO+CaO+SrO+BaO: 15-40%. The glass substrate has an alkali metal oxide content of 0-0.1% as represented by mole percentage based on oxides. The glass substrate has an average coefficient of thermal expansion ? of 56-90 (×10?7/° C.) at 50° C.-350° C.

Abstract: The present invention provides a glass substrate in which in a step of sticking a glass substrate and a silicon-containing substrate to each other, bubbles hardly intrude therebetween. The present invention relates to a glass substrate for forming a laminated substrate by lamination with a silicon-containing substrate, having a warpage of 2 ?m to 300 ?m, and an inclination angle due to the warpage of 0.0004° to 0.12°.

Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: To provide a method for producing chemically tempered glass, whereby frequency of replacement of the molten salt can be reduced. A method for producing chemically tempered glass, which comprises repeating ion exchange treatment of immersing glass in a molten salt, wherein the glass comprises, as represented by mole percentage, from 61 to 77% of SiO2, from 1 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 6% of K2O; SiO2+Al2O3 is from 65 to 85%; MgO+CaO is from 3 to 15%; and R calculated by the following formula by using contents of the respective components, is at least 0.66: R=0.029×SiO2+0.021×Al2O3+0.016×MgO?0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O?2.

Abstract: A glass for chemical tempering is provided. The glass contains as represented by mole percentage based on the following oxides, from 61 to 77% of SiO2, from 11 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 0.5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 1.9% of K2O; wherein an R value calculated by the following formula by using contents of the respective components, is at least 0.66: R=0.029×SiO2+0.021×Al2O3+0.016×MgO?0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O?2.

Abstract: A chemically strengthened glass sheet, which has front and back main surfaces and an edge surface between the front and back main surfaces, has undergone a chemical strengthening treatment and has an approximately rectangular shape, in which the chemically strengthened glass sheet has a surface compressive stress of 800 MPa or more, and an internal tensile stress of 42 MPa or less.

Abstract: To provide a method for producing chemically tempered glass, whereby frequency of replacement of the molten salt can be reduced. A method for producing chemically tempered glass, which comprises repeating ion exchange treatment of immersing glass in a molten salt, wherein the glass comprises, as represented by mole percentage, from 61 to 77% of SiO2, from 1 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 6% of K2O; SiO2+Al2O3 is from 65 to 85%; MgO+CaO is from 3 to 15%; and R calculated by the following formula by using contents of the respective components, is at least 0.66: R=0.029×SiO2+0.021×Al2O3+0.016×MgO?0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O?2.

Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: To provide glass to be used for chemically tempered glass which is hardly broken even when flawed. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 65 to 85% of SiO2, from 3 to 15% of Al2O3, from 5 to 15% of Na2O, from 0 and less than 2% of K2O, from 0 to 15% of MgO and from 0 to 1% of ZrO2, and has a total content Si02+Al2O3 of SiO2 and Al2O3 of at most 88%.

Abstract: To provide glass to be used for chemically tempered glass which is hardly broken even when flawed. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 65 to 85% of SiO2, from 3 to 15% of Al2O3, from 5 to 15% of Na2O, from 0 and less than 2% of K2O, from 0 to 15% of MgO and from 0 to 1% of ZrO2, and has a total content SiO2+Al2O3 of SiO2 and Al2O3 of at most 88%.

Abstract: To provide glass to be used for chemically tempered glass which is hardly broken even when flawed. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 65 to 85% of SiO2, from 3 to 15% of Al2O3, from 5 to 15% of Na2O, from 0 and less than 2% of K2O, from 0 to 15% of MgO and from 0 to 1% of ZrO2, and has a total content SiO2+Al2O3 of SiO2 and Al2O3 of at most 88%.

Abstract: To provide a method for producing chemically tempered glass, whereby frequency of replacement of the molten salt can be reduced. A method for producing chemically tempered glass, which comprises repeating ion exchange treatment of immersing glass in a molten salt, wherein the glass comprises, as represented by mole percentage, from 61 to 77% of SiO2, from 1 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 6% of K2O; SiO2+Al2O3 is from 65 to 85%; MgO+CaO is from 3 to 15%; and R calculated by the following formula by using contents of the respective components, is at least 0.66: R=0.029×SiO2+0.021×Al2O3+0.016×MgO?0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O?2.