The present invention relates to a method for producing crystallized glass, including: (a1) melting a glass raw material to obtain molten glass; (a2) molding the molten glass into a predetermined shape by a molding unit to obtain a glass molded body; (a3) slowly cooling the glass molded body to obtain a raw glass plate containing at least one of a crystal nucleus and a separated phase; and (a4) heat-treating the raw glass plate containing the at least one of the crystal nucleus and the separated phase to cause crystal growth so as to obtain the crystallized glass.

The disclosure relates to a method for manufacturing an optical element, where a blank of glass is heated and/or provided and, after heating and/or after being provided between a first mold (UF) and at least one second mold (OF), is press molded, for example on both sides, to form the optical element and is then sprayed with a surface treatment agent.

In a method of manufacturing a tube of quartz glass by molding a hollow cylinder having a wall thickness of at least 20 mm, the cylinder is continuously fed under rotation about a rotational axis into a heating zone at a relative feed rate V.sub.C, softened and radially expanded under the effect of a gas pressure. A tube strand is continuously formed and is withdrawn at a withdrawal rate V.sub.T. In order to mold thick-walled initial hollow cylinders of quartz glass into tubes with larger diameter, the gas pressure is used as an actuating variable of a diameter regulation for the tube outer diameter or for a geometrical correlated parameter thereof, and in a pressure build-up phase the gas pressure is gradually increased from a lower initial value to a higher final value, and that the following applies to the ratio of V.sub.C and V.sub.T:V.sub.T=V.sub.C0.2.Math.V.sub.C.

A white glass container derived from a phase separation phenomenon of a halogen-free glass composition includes a neck portion and a body portion. The glass composition includes as ingredients at least SiO.sub.2, P.sub.2O.sub.5, Al.sub.2O.sub.3, B.sub.2O.sub.3, R.sub.2O (RNa or K), MgO, CaO and the like. The neck portion and the body portion respectively have a white multilayer structure formed to successively include a white transparent layer of relatively low white coloration and a white opaque layer of relatively high white coloration from the outer surface side. The contents of P.sub.2O.sub.5 in the white transparent layer are made smaller than the contents of P.sub.2O.sub.5 in the white opaque layer.

A glass manufacturing apparatus configured to manufacture glass through a process of lowering the temperature of a non-contact supported glass material. The glass manufacturing apparatus comprises a heating unit configured to heat the glass material; and a forming unit configured to form the molten glass material while its temperature decreases after the heating by the heating unit has stopped.

Glass and glass ceramic compositions having at least a lithium disilicate crystalline phase, a petalite crystalline phase, and a residual glass phase along with methods of making the glass and glass ceramic compositions are described. The compositions are compatible with conventional rolling and float processes, are transparent or translucent, and have high mechanical strength and fracture resistance. Additionally, processes of 3D forming glass ceramic preforms having the glass ceramic composition discussed to produce glass ceramic articles are described. Further, the compositions are able to be chemically tempered to even higher strength glass ceramics that are useful as large substrates in multiple applications.

The present invention provides an infrared-transmitting glass that is a chalcogenide glass, has a reduced Ge content, can sufficiently cover atmospheric windows, is free from highly toxic elements, such as Se and As, and is suitable for mold forming. Specifically, the present invention provides an infrared-transmitting glass suitable for mold forming, comprising, in terms of molar concentration: 0 to 2% of Ge, 3 to 30% of Ga, 10 to 40% of Sb, 45 to 70% of S, 3 to 30% of at least one member selected from the group consisting of Sn, Ag, Cu, Te, and Cs, and 0 to 30% of at least one member selected from the group consisting of Cl, Br, and I.

A parallelepipedal low-pressure plasma chamber body of glass is disclosed. The low-pressure plasma chamber may have electrodes at opposing sides of the low-pressure plasma chamber body. Furthermore, the low-pressure plasma chamber may have at opposing sides a door and a rear wall closure. The door and rear wall closure may in each case have at least one media connection in order to achieve a uniform gas flow in the low-pressure plasma chamber. The door may be assembled on the collar of the low-pressure plasma chamber body which extends radially away from the longitudinal axis of the low-pressure plasma chamber body. The low-pressure plasma chamber body is preferably produced using the pressing method or blow-and-blow method, in an analogous manner to industrial glass bottle production.

A multiple mold (42) for production of at least two glass-ceramic blanks. The glass-ceramic blanks are for dental purposes and are produced from at least two powder blanks by hot pressing. The multiple mold (42) includes a frame (48) that defines at least sections of a receiving volume (50) for the at least two powder blanks. Additionally provided is a separating element (52) which is disposed within the receiving volume (50) and divides the receiving volume (50) into at least two subvolumes, each of which is designed to accommodate one of the at least two powder blanks. Also described are the use of the multiple mold (42) for production of a glass-ceramic blank for dental purposes, a compression apparatus and a continuous system for production of glass-ceramic blanks for dental purposes.

A method for further processing of a glass tube semi-finished product includes: providing the glass tube semi-finished product, along with tube-specific data for the glass tube semi-finished product; reading the tube-specific data for the glass tube semi-finished product; and further processing of the glass tube semi-finished product including a step of thermal forming carried out at least in sections. At least one process parameter during the further processing of the glass tube semi-finished product including the step of thermal forming carried out at least in sections is controlled as a function of the tube-specific data for the glass tube semi-finished product. In this way, the further processing can be matched more efficiently to the particular characteristics of a glass tube semi-finished product to be processed or a particular subsection thereof, and the relevant characteristics of the particular glass tube semi-finished product do not need to be measured again.