Abstract: The present invention relates to a glass including, in terms of mole percentage based on oxides: SiO2 in an amount of 45% to 65%; Al2O3 in an amount of 18% to 30%; Li2O in an amount of 7% to 15%; one or more selected from Y2O3 and La2O3 in a total amount of 0% to 10%; P2O5 in an amount of 0% to 10%; B2O3 in an amount of 0% to 10%; and ZrO2 in an amount of 0% to 4%, and satisfying the following expression: [Al2O3]—[R2O]—[RO]—[P2O5]>0, provided that, in terms of mole percentage based on oxides, a content of Al2O3 is defined as [Al2O3], a content of P2O5 is defined as [P2O5], a total content of alkali metal oxides is defined as [R2O], and a total content of alkali earth metal oxides is defined as [RO].

Abstract: An inference method includes inferring a value that includes a stress value in a region located 50 ?m or shallower from a surface of a chemically strengthened glass, by receiving as input at least a temperature and a time used upon chemical strengthening, and stress values at three or more different depth positions 20 ?m or deeper from the surface of the chemically strengthened glass that has been obtained by chemically strengthening a glass having a thickness of 0.2 mm or greater with the temperature and the time.

Abstract: The present invention relates to a chemically strengthened glass article in which a compressive stress value on a first surface is 400 MPa or more, with a glass thickness of t (?m), the compressive stress value at the depth DB where the compressive stress value is maximum in the range where the depth from the first surface is (0.05×t)-(0.15×t) ?m is larger than the compressive stress value at the depth DA where the compressive stress value is minimum in the range from the first surface to the depth DB, the tensile stress value at a depth (0.5×t) ?m from the first surface is 125 MPa or less, and a compressive stress layer depth is (0.23×t) ?m or more.

Abstract: The present invention relates to a chemically strengthened glass satisfying A1 [MPa] of 600 or more, A2 [MPa] of 50 or more, B1 [?m] of 6 or less, B2 [?m] of 10% or more of t [?m], C [MPa] of ?30 or less, and A1/B1 [MPa/?m] of 100 or more when the chemically strengthened glass has a thickness t [?m] and a profile of a stress value [MPa] at a depth x [?m] from a glass surface is approximated by an error least-squares method in a region of 0<x<3t/8 using the following function while defining a compressive stress as positive and a tensile stress as negative: A1erfc(x/B1)+A2erfc(x/B2)+C, in which erfc is a complementary error function, and relations of A1>A2 and B1<B2 are satisfied.

Abstract: The present invention relates to a glass including, in mole percentage on an oxide basis: 60-75% of SiO2; 8-20% of Al2O3; 5-16% of Li2O; and 2-15% of one or more kinds of Na2O and K2O in total, in which a ratio PLi of the content of Li2O to a total content of Li2O, Na2O, and K2O is 0.40 or more, and a total content of MgO, CaO, SrO, BaO, and ZnO is 0-10%.

Abstract: The present invention relates to a chemically strengthened glass satisfying A1 [MPa] of 600 or more, A2 [MPa] of 50 or more, B1 [?m] of 6 or less, B2 [?m] of 10% or more of t [?m], C [MPa] of ?30 or less, and A1/B1 [MPa/?m] of 100 or more when the chemically strengthened glass has a thickness t [?m] and a profile of a stress value [MPa] at a depth x [?m] from a glass surface is approximated by an error least-squares method in a region of 0<x<3t/8 using the following function while defining a compressive stress as positive and a tensile stress as negative: A1erfc(x/B1)+A2erfc(x/B2)+C, in which erfc is a complementary error function, and relations of A1>A2 and B1<B2 are satisfied.

Abstract: The present invention provides crystallized glass of three-dimensional shape for easily producing chemically strengthened glass of three-dimensional shape that resists damage and has exceptional transparency. This crystallized glass of three-dimensional shape: contains crystals; has light transmittance in terms of a thickness of 0.8 mm of 80% or higher; and contains 45-74% SiO2, 1-30% Al2O3, 1-25% Li2O, 0-10% Na2O, 0-5% K2O, a total of 0-15% of SnO2 and/or ZrO2, and 0-12% P2O5, these amounts expressing the oxide-based mass percentage.

Abstract: The present invention relates to a glass including, in mole percentage in terms of oxides: 40-65% of SiO2; 25-40% of Al2O3; and 7-15% of one or more components, in total, selected from Y2O3, La2O3, Nb2O5, Ta2O5, and WO3. Also the present invention relates to a chemically strengthened glass having a base composition including, in mole percentage in terms of oxides: 40-65% of SiO2; 25-40% of Al2O3; 7-15% of Y2O3; and 2-15% of Li2O, and having a compressive stress value, measured at a depth of 50 ?m from a surface thereof, of 150 MPa or more.

Abstract: The present invention relates to a chemically strengthened glass having a sheet shape, having a compressive stress layer on a glass surface, having a compressive stress value on the glass surface of 800 MPa or more, having a sheet thickness (t) of 100 ?m or more, having a depth of the compressive stress layer (DOL) of (t×0.1) ?m or more, and satisfying: CSB>CSA>0, where DB is a depth in a range of 10 ?m or more and not more than DOL from the glass surface, at which a compressive stress value is maximum; CSB is the compressive stress value at the depth DB; D? is a depth in a range of equal to or less than DB from the glass surface, at which a compressive stress value is minimum; and CSA is the compressive stress value at the depth DA.

Abstract: The present invention relates to a chemically strengthened glass sheet in which a value of SB/(SA×t) is 5.0 mm?1 or more, where SA (MPa·?m) is an integrated value of a compressive stress from a surface of the glass sheet to a depth of 10 ?m, SB (MPa·?m) is an integrated value of a compressive stress from the depth of 10 ?m to DOL which is a depth at which the compressive stress is zero, and t (mm) is a thickness of the glass sheet.

Abstract: The present invention relates to a glass having a fracture toughness value of 0.85 MPa·m1/2 or more, and including, as represented by molar percentage based on oxides, 40% or more of SiO2, 20% or more of Al2O3, 5% or more of Li2O, and from 1 to 6% in total of one or more selected from Y2O3, La2O3 and Ga2O3. The present invention relates to a glass including, as represented by molar percentage based on oxides, from 40 to 60% of SiO2, from 20 to 45% of Al2O3, and from 5 to 15% of Li2O. Denoting the content of SiO2 as [SiO2] and the content of Al2O3 as [Al2O3], (2×[Al2O3]-X)/[SiO2] is 0 or more and 1 or less.

Abstract: A glass ball has a density of 2.3 to 3.2 g/cm3, a Young's modulus of 60 to 150 GPa, and an average coefficient of thermal expansion at 50 to 350° C. being 40×10?7 to 120×10?7/° C. The glass ball is formed of a glass material including, as represented by mole percentage based on oxides, 30 to 75 mol % of SiO2, 2 to 30 mol % of Al2O3, and 5 to 25 mol % of R2O, where R is at least one kind selected from Li, Na and K. The glass ball includes a compressive stress layer in a surface thereof.

Abstract: The present invention provides crystallized glass of three-dimensional shape for easily producing chemically strengthened glass of three-dimensional shape that resists damage and has exceptional transparency. This crystallized glass of three-dimensional shape: contains crystals; has light transmittance in terms of a thickness of 0.8 mm of 80% or higher; and contains 45-74% SiO2, 1-30% Al2O3, 1-25% Li2O, 0-10% Na2O, 0-5% K2O, a total of 0-15% of SnO2 and/or ZrO2, and 0-12% P2O5, these amounts expressing the oxide-based mass percentage.

Abstract: The purpose of the present invention is to provide a chemically strengthened glass having excellent transparency and strength and being scratch resistant. The present invention pertains to a chemically strengthened glass that: has a compressive stress layer on the surface thereof; has a visible light transmittance of at least 70% when the thickness thereof is converted to 0.8 mm; has a surface compressive stress of at least 600 MPa; has a compressive stress depth of at least 80 ?m; and contains a ?-spodumene.

Abstract: A glass ball has a density of 2.3 to 3.2 g/cm3, a Young's modulus of 60 to 150 GPa, and an average coefficient of thermal expansion at 50 to 350° C. being 40×10?7 to 120×10?7/° C. The glass ball is formed of a glass material including, as represented by mole percentage based on oxides, 30 to 75 mol % of SiO2, 2 to 30 mol % of Al2O3, and 5 to 25 mol % of R2O, where R is at least one kind selected from Li, Na and K. The glass ball includes a compressive stress layer in a surface thereof.

Abstract: A plate-like chemically strengthened glass having a compression stress layer on the surface of the glass, wherein the compressive stress value (CS0) at the glass surface of is 500 MPa or more, the plate thickness (t) is 400 ?m or more, the compressive stress depth of layer (DOL) is (t×0.15) ?m or more, the compressive stress values (CS1) and (CS2) when the depth from the glass surface is ¼ and ½, respectively, are 50 MPa or more, m1 expressed by {m1=(CS1?CS2/(DOL/4?DOL/2)} is ?1.5 MPa/?m or more, m2 expressed by {m2=(CS2/(DOL/2?DOL)} is 0 MPa/?m or less, and m2 is less than m1.

Abstract: The present invention relates to a chemically strengthened glass satisfying A1 [MPa] of 600 or more, A2 [MPa] of 50 or more, B1 [?m] of 6 or less, B2 [?m] of 10% or more of t [?m], C [MPa] of ?30 or less, and A1/B1 [MPa/?m] of 100 or more when the chemically strengthened glass has a thickness t [?m] and a profile of a stress value [MPa] at a depth x [?m] from a glass surface is approximated by an error least-squares method in a region of 0<x<3t/8 using the following function while defining a compressive stress as positive and a tensile stress as negative: A1erfc(x/B1)+A2erfc(x/B2)+C, in which erfc is a complementary error function, and relations of A1>A2 and B1<B2 are satisfied.

Abstract: Provided are a glass body for pressure forming enabling press forming in a low-temperature range without the need of a special mold material, and a method for manufacturing the same. A glass body for pressure forming 1 having a porosified layer 1b formed by porosifying a surface thereof and having a Vickers hardness of 85 N/mm2 or less on the porosified surface. The porosified layer 1b can be manufactured by phase-separating the glass body by spinodal decomposition, acid-treating the phase-separated glass body and then treating the acid-treated glass body with alkali or hot water to porosify the surface of the glass body.

Abstract: To provide a glass ceramic composition with which a substrate for a light emitting element having a high reflectance and a high thermal conductivity can be obtained, and which can suppress breakage at the time of production of the substrate for a light emitting element. A glass ceramic composition to be used for production of a substrate on which a light emitting element is to be mounted, which comprises from 30 to 45 mass % of a glass powder, from 35 to 50 mass % of an alumina powder and from 10 to 30 mass % of a zirconia powder, to the total amount of the glass powder, the alumina powder and the zirconia powder, wherein the average particle size of the zirconia powder is at most ¼ of the average particle size of the alumina powder.

Abstract: Provided is a light-emitting device provided with a light reflection layer which has a high light reflectivity and which is less susceptible to deterioration of the reflectivity due to corrosion, and having an improved light extraction efficiency. A light-emitting device comprising a substrate having a conductor layer formed on its surface and a light-emitting element disposed on the conductor layer, characterized in that an overcoat layer is formed between the conductor layer and the light-emitting element, and the overcoat layer is a borosilicate glass which comprises, as represented by mol % based on oxides, from 62 to 84% of SiO2, from 10 to 25% of B2O3, from 0 to 5% of Al2O3 and from 0 to 5% in total of at least one of Na2O and K2O, provided that the total content of SiO2 and Al2O3 is from 62 to 84%, and may contain from 0 to 10% of MgO and at least one of CaO, SrO and BaO in a total content of at most 5%.