The present invention relates to a glass for a pharmaceutical container that is excellent in ultraviolet shielding ability, and is also excellent in chemical durability. The glass for a pharmaceutical container of the present invention includes as a glass composition, in terms of mass %, 67% to 81% of SiO.sub.2, more than 4% to 7% of Al.sub.2O.sub.3, 7% to 14% of B.sub.2O.sub.3, 3% to 12% of Na.sub.2O+K.sub.2O, 0% to 1.8% of CaO+BaO, 0.5% to less than 2% of Fe.sub.2O.sub.3, and 1% to 5% of TiO.sub.2, and satisfies a relationship of CaO/BaO≤0.5.

The present invention relates to a glass for a pharmaceutical container that is excellent in ultraviolet shielding ability, and is also excellent in chemical durability. The glass for a pharmaceutical container of the present invention includes as a glass composition, in terms of mass %, 67% to 81% of SiO.sub.2, more than 4% to 7% of Al.sub.2O.sub.3, 7% to 14% of B.sub.2O.sub.3, 3% to 12% of Na.sub.2O+K.sub.2O, 0% to 1.8% of CaO+BaO, 0.5% to less than 2% of Fe.sub.2O.sub.3, and 1% to 5% of TiO.sub.2, and satisfies a relationship of CaO/BaO≤0.5.

A glass-ceramic comprising, in weight percent on an oxide basis, of 50 to 70% SiO.sub.2, 0 to 20% Al.sub.2O.sub.3, 12 to 23% MgO, 0 to 4% Li.sub.2O, 0 to 10% Na.sub.2O, 0 to 10% K.sub.2O, 0 to 5% ZrO.sub.2, and 2 to 12% F, wherein the predominant crystalline phase of said glass-ceramic is a trisilicic mica, a tetrasilicic mica, or a mica solid solution between trisilicic and tetrasilicic, and wherein the total of Na.sub.2O+Li.sub.2O is at least 2 wt. %; wherein the glass-ceramic can be ion-exchanged.

A glass-ceramic comprising, in weight percent on an oxide basis, of 50 to 70% SiO.sub.2, 0 to 20% Al.sub.2O.sub.3, 12 to 23% MgO, 0 to 4% Li.sub.2O, 0 to 10% Na.sub.2O, 0 to 10% K.sub.2O, 0 to 5% ZrO.sub.2, and 2 to 12% F, wherein the predominant crystalline phase of said glass-ceramic is a trisilicic mica, a tetrasilicic mica, or a mica solid solution between trisilicic and tetrasilicic, and wherein the total of Na.sub.2O+Li.sub.2O is at least 2 wt. %; wherein the glass-ceramic can be ion-exchanged.

Glass-based articles that include a compressive stress layer extending from a surface of the glass-based article to a depth of compression are formed by exposing glass-based substrates to water vapor containing environments. The glass-based substrates have compositions selected to avoid the formation of haze during the treatment process. The methods of forming the glass-based articles may include elevated pressures and/or multiple exposures to water vapor containing environments selected to avoid the formation of haze during the treatment process.

Glass-based articles that include a compressive stress layer extending from a surface of the glass-based article to a depth of compression are formed by exposing glass-based substrates to water vapor containing environments. The glass-based substrates have compositions selected to avoid the formation of haze during the treatment process. The methods of forming the glass-based articles may include elevated pressures and/or multiple exposures to water vapor containing environments selected to avoid the formation of haze during the treatment process.

Crystallized glass and strengthened crystallized glass with a novel composition, which have a high refractive index and high hardness, are provided. A crystallized glass, including, by mass % in terms of oxide, 20.0% or more and less than 40.0% of a SiO.sub.2 component, more than 0% and 20.0% or less of a Rn.sub.2O component, where Rn is one or more selected from Li, Na, and K, 7.0% to 25.0% of an Al.sub.2O.sub.3 component, 0% to 25.0% of a MgO component, 0% to 45.0% of a ZnO component, and 0% to 20.0% of a Ta.sub.2O.sub.5 component, in which a total amount of the MgO component, the ZnO component, and the Ta.sub.2O.sub.5 component is 10.0% or more.

Crystallized glass and strengthened crystallized glass with a novel composition, which have a high refractive index and high hardness, are provided. A crystallized glass, including, by mass % in terms of oxide, 20.0% or more and less than 40.0% of a SiO.sub.2 component, more than 0% and 20.0% or less of a Rn.sub.2O component, where Rn is one or more selected from Li, Na, and K, 7.0% to 25.0% of an Al.sub.2O.sub.3 component, 0% to 25.0% of a MgO component, 0% to 45.0% of a ZnO component, and 0% to 20.0% of a Ta.sub.2O.sub.5 component, in which a total amount of the MgO component, the ZnO component, and the Ta.sub.2O.sub.5 component is 10.0% or more.

The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CS.sub.x [MPa,] at a depth x [.Math.m] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CS.sub.x" of the stress value CS.sub.x in the profile satisfies the following expression within a range of CS.sub.x≥0: 0<CS.sub.x"≤0.050.

The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CS.sub.x [MPa,] at a depth x [.Math.m] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CS.sub.x" of the stress value CS.sub.x in the profile satisfies the following expression within a range of CS.sub.x≥0: 0<CS.sub.x"≤0.050.