Provided is a method that enables a crystal-free glass material to be stably produced by a containerless levitation technique. A glass material 30 has a first surface 31 facing a forming surface 10a and a second surface 32 located on a side opposite to the forming surface 10a. The first surface 31 includes a central portion 31a and a peripheral portion 31b located outside of the central portion 31a. Gas is jetted through a gas jet hole at a flow velocity and a flow volume at which a glass material satisfying R.sub.2<R.sub.3<R.sub.1 is formed where R.sub.1 represents a radius of curvature of the central portion 31a, R.sub.2 represents a radius of curvature of the peripheral portion 31b, and R.sub.3 represents a radius of curvature of the second surface 32.

Additive manufacturing processes for making transparent three-dimensional parts from inorganic material powders involve selective use of vacuum to remove or avoid trapped bubbles in the parts.

A method of forming a glass container includes providing a glass parison having a tubular wall that includes an inside surface, which defines an interior parison cavity open at one axial end of the tubular wall, and an outside surface. The tubular wall includes an expandable blow portion that has a forming viscosity between 10.sup.7.5 Pa.Math.s and 10.sup.5.5 Pa.Math.s and is also in an isoviscous state. The glass parison is blow molded into a glass container by introducing a compressed gas into the interior parison cavity to thereby cause the expandable blow portion of the tubular wall to expand outwardly into a portion of a wall that defines the glass container.

A method of forming a glass body, the method including pressing titania-doped silica soot to form a molded body, consolidating the molded body by heating the molded body, annealing the consolidated molded body, and polishing at least one surface of the annealed molded body to form the glass body. After the polishing, the at least one surface of the glass body has a waviness amplitude of about 0.60 nm or less in the spatial frequency range of 0.05 mm.sup.1 or more and 0.2 mm.sup.1 or less.

The present invention relates to a glass ceramic powder comprising i) a glass material formed from a glass mixture containing a lithium and oxygen containing compound selected from Li.sub.2O and/or Li.sub.2CO.sub.3, SiO.sub.2, K.sub.2O, La.sub.2O.sub.3, and ii) seed particles comprising Li.sub.2SiO.sub.3 crystals and/or Li.sub.2Si.sub.2O.sub.5 crystals. The present invention also relates to a method of manufacturing of said glass ceramic powder, a method for preparing compacted and sintered bodies from the glass ceramic powder and bodies obtainable by said method.

Provided is a method that can manufacture a glass material having excellent homogeneity by containerless levitation. With a block (12) of glass raw material held levitated above a forming surface (10a) of a forming die (10) by jetting gas through a gas jet hole (10b) opening on the forming surface (10a), the block (12) of glass raw material is heated and melted by irradiation with laser beam, thus obtaining a molten glass, and the molten glass is then cooled to obtain a glass material. Control gas is jetted to the block (12) of glass raw material along a direction different from a direction of jetting of the levitation gas for use in levitating the block (12) of glass raw material or the molten glass.

A method of manufacturing a glass-phosphor composite is disclosed. The method comprises: preparing rare earth ion-containing parent glass; mixing the rare-earth ion-containing parent glass in a power state with a phosphor in a powder state; and providing a glass-phosphor composite using the powder mixture of the rare earth ion-containing parent glass and the phosphor, wherein the mixing includes mixing the rare earth ion-containing parent glass in the powder state with the phosphor in the powder state so that the phosphor in the glass-phosphor composite is in an amount of 5 wt % to 30 wt %, and the preparing includes using a glass frit having a glass transition point of 300 C. to 800 C. and a sintering temperature of 200 C. to 600 C.

Glass ceramics having SiO.sub.2 as main crystal phase and precursors thereof are described which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

One aspect is a reflective member, which has a laminated structure in which transparent quartz glass members are formed on an upper surface and a lower surface of an opaque siliceous sintered powder layer. The opaque siliceous sintered powder layer has a thickness of 0.1 mm or more and a thickness distribution of 0.05 mm or less. When a load is applied to each of the transparent quartz glass members on an upper surface and a lower surface of the laminated structure in a direction parallel to the laminated structure, the reflective member is fractured at a load of 5 N or more per square centimeter. The laminated structure includes a semi-transparent portion having a width of 0.01 mm or less, which has an intermediate opacity between an opacity of the opaque siliceous sintered powder layer and an opacity of each of the transparent quartz glass members.

Glass ceramics having SiO.sub.2 as main crystal phase and precursors thereof are described which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.