A glass comprising at least one oxide of Si and a di- or higher-valent metal element, the glass containing no bubbles with diameters of more than 0.1 mm, wherein an occupied area fraction of bubbles with diameters of 0.1 mm or less is 0.05% or less. A. semiconductor production apparatus and a liquid crystal production apparatus comprising a glass member comprising this glass. A method for producing a glass, comprising the steps of (1) placing raw material powders for at least one oxide of Si and a di- or higher-valent metal element in a container, mixing the raw material powders together and then melting the mixture by heating under reduced pressure to obtain a melt; (2-1) pressurizing the melt in a He gas atmosphere, or (2-2) heating the melt in an inert gas atmosphere other than a He gas atmosphere and then pressurizing the melt in the inert gas atmosphere; and (3) cooling the melt.

A glass comprising at least one oxide of Si and a di- or higher-valent metal element, the glass containing no bubbles with diameters of more than 0.1 mm, wherein an occupied area fraction of bubbles with diameters of 0.1 mm or less is 0.05% or less. A. semiconductor production apparatus and a liquid crystal production apparatus comprising a glass member comprising this glass. A method for producing a glass, comprising the steps of (1) placing raw material powders for at least one oxide of Si and a di- or higher-valent metal element in a container, mixing the raw material powders together and then melting the mixture by heating under reduced pressure to obtain a melt; (2-1) pressurizing the melt in a He gas atmosphere, or (2-2) heating the melt in an inert gas atmosphere other than a He gas atmosphere and then pressurizing the melt in the inert gas atmosphere; and (3) cooling the melt.

The present invention relates to a glass ceramic material comprising a core-rim structure, wherein the core-rim structure comprises an amorphous SiO.sub.2 matrix, ZrO.sub.2 crystals, and hardness-enhancing additive, the ZrO.sub.2 crystals are present in cores that are at least partly surrounded by a rim comprising hardness-enhancing additive.

Disclosed herein are laminated glass articles having a hard scratch resistant outer surface. In some embodiments, the laminated glass article includes a glass core layer and a glass clad layer. In some embodiments, the laminated glass article includes a glass core layer sandwiched between two glass clad layers. In some embodiments, the clad glass is selected from the group of consisting of: aluminate glasses; oxynitride glasses; rare earth/transition metal glasses; beryl glasses; and glasses containing lithium, zirconium, or both lithium and zirconium. Such glass compositions can thus be used in forming the clad layer.

Disclosed herein are laminated glass articles having a hard scratch resistant outer surface. In some embodiments, the laminated glass article includes a glass core layer and a glass clad layer. In some embodiments, the laminated glass article includes a glass core layer sandwiched between two glass clad layers. In some embodiments, the clad glass is selected from the group of consisting of: aluminate glasses; oxynitride glasses; rare earth/transition metal glasses; beryl glasses; and glasses containing lithium, zirconium, or both lithium and zirconium. Such glass compositions can thus be used in forming the clad layer.

Provided is a chemically strengthened optical glass with improved crack resistance and high hardness, in which the refractive index, the Abbe number, and the transmittance required for a conventional optical glass are maintained.

The chemically strengthened optical glass includes a compressive stress layer on a surface, and contains, by mass % in terms of oxide: 20.0% to 50.0% of a SiO.sub.2 component, 10.0% to 45.0% of a TiO.sub.2 component, and 0.1 to 20.0% of a Na.sub.2O component, and the chemically strengthened optical glass is characterized in that an Hv change rate defined as [(Hv.sub.after−Hv.sub.before)/Hv.sub.before]×100 is equal to or greater than 3.0%.

Provided is a chemically strengthened optical glass with improved crack resistance and high hardness, in which the refractive index, the Abbe number, and the transmittance required for a conventional optical glass are maintained.

The chemically strengthened optical glass includes a compressive stress layer on a surface, and contains, by mass % in terms of oxide: 20.0% to 50.0% of a SiO.sub.2 component, 10.0% to 45.0% of a TiO.sub.2 component, and 0.1 to 20.0% of a Na.sub.2O component, and the chemically strengthened optical glass is characterized in that an Hv change rate defined as [(Hv.sub.after−Hv.sub.before)/Hv.sub.before]×100 is equal to or greater than 3.0%.

An environment-friendly glass material, including components like SiO.sub.2, ZnO, alkali metal oxide and S, but does not contain Cd, wherein when the thickness of the environment-friendly glass material is 3 mm, the cutoff wavelength is above 550 nm, the transmittance at 800-850 nm is above 75%, the transmittance at 850-900 nm is above 80%, the transmittance at 900-1000 nm is above 83%, and the transmittance at 1000-2000 nm is above 85%. Through rational component design, the glass material of the present invention realizes environmental protection, UV and visible light cutoff, and high near-infrared transmittance at the same time.

An environment-friendly glass material, including components like SiO.sub.2, ZnO, alkali metal oxide and S, but does not contain Cd, wherein when the thickness of the environment-friendly glass material is 3 mm, the cutoff wavelength is above 550 nm, the transmittance at 800-850 nm is above 75%, the transmittance at 850-900 nm is above 80%, the transmittance at 900-1000 nm is above 83%, and the transmittance at 1000-2000 nm is above 85%. Through rational component design, the glass material of the present invention realizes environmental protection, UV and visible light cutoff, and high near-infrared transmittance at the same time.

A radically polymerizable dental material having at least one radically polymerizable monomer without acid groups, at least one radically polymerizable monomer containing an acid group, at least one fluoroaluminosilicate glass filler and/or radiopaque glass filler, and at least one initiator for the radical polymerization, wherein the filler is an acid-treated fluoroaluminosilicate glass filler and/or radiopaque glass filler.