A process and a plant produce hollow microspheres made of glass. According to the process an aqueous suspension is prepared from starting materials containing glass powder and water glass, feedstock particles having a diameter between 5 ?m and 300 ?m, in particular between 5 ?m and 100 ?m, being produced from the suspension. The feedstock particles are mixed with a pulverulent release agent made of aluminum hydroxide in an intensive mixer. The mixture of feedstock particles and release agent is subsequently introduced into a firing chamber of a furnace. The feedstock particles expand in the firing chamber, at a firing temperature which exceeds the softening temperature of the glass powder, to form the hollow microspheres.

A printing material and process for producing dense glass-ceramic articles by additive manufacturing are provided. The printing material includes a glass fit that densifies to a degree that closely approximates the theoretical density before appreciable crystallization occurs. Densification without interference from a crystalline phase enables greater degrees of densification. Further heating of the sintered printing material induces crystallization to form glass-ceramic articles having a density approaching the theoretical density. The printing material and process enable production of high density glass-ceramic articles at modest process temperatures.

A method of manufacturing a polarizing glass sheet includes subjecting, while heating, a glass preform sheet containing metal halide particles to down-drawing, to thereby provide a glass member having stretched metal halide particles dispersed in an aligned manner in a glass matrix, and subjecting the glass member to reduction treatment to reduce the stretched metal halide particles, to thereby provide a polarizing glass sheet. A shape of the glass preform sheet during the down-drawing satisfies a relationship of the following expression:
L.sub.1/W.sub.11.0
where L.sub.1 represents a length between a portion in which a width of the glass preform sheet has changed to 0.8 times an original width and a portion in which the width of the glass preform sheet has changed to 0.2 times the original width W.sub.0, and W.sub.1 represents a length equivalent to 0.5 times the original width W.sub.0 of the glass preform sheet.

A glass object that includes a first colored glass article, a second transparent glass layer in contact with the first glass article and having an exterior surface and a thickness, and an image formed from particles of cremated remains, the image being disposed within the thickness of the second glass layer between the first colored glass article and the exterior surface of the second glass layer and being free from contact with the first glass article, and a method of making the same.

The present invention pertains to glass containing, in terms of mass % on an oxide basis, 40-80% of SiO.sub.2, 1-30% of Al.sub.2O.sub.3, and 1-40% of CaO, the glass having dmisteinbergite as the crystalline phase. Such glass makes it difficult for cracks to progress and has exceptional crack resistance.

The present invention relates to a plasma-resistant glass, chamber interior parts for a semiconductor manufacturing process, and methods for manufacturing same, and specifically, to a plasma-resistant glass and a method for manufacturing same, wherein the content of components of the plasma-resistant glass can be controlled to reduce the thermal expansion coefficient of the glass and thereby prevent the glass from being damaged due to thermal shock when used at a high-temperature.

A glass composition includes from 60 mol % to 76 mol % SiO.sub.2; from 7 mol % to 16 mol % Al.sub.2O.sub.3; from 0 mol % to 12 mol % B.sub.2O.sub.3; and from 0 mol to 14 mol % Na.sub.2O. (R.sub.2O+RO)/Al.sub.2O.sub.3 in the glass composition may be greater than or equal to 1. A glass laminate article includes a core glass layer having a low temperature coefficient of thermal expansion (LTCTE.sub.core) and a high temperature coefficient of thermal expansion (HTCTE.sub.core): a clad glass layer laminated to a surface of the core glass layer, the clad glass layer having a low temperature coefficient of thermal expansion (LTCTE.sub.clad) and a high temperature coefficient of thermal expansion (HTCTE.sub.clad); and a thickness t.

One aspect is a process to producing a synthetic quartz glass, including an annealing treatment that includes: putting a synthetic quartz glass as a parent material into a heat treatment furnace; elevating a temperature in the heat treatment furnace to a prescribed keeping temperature that is equal to or higher than the annealing point; keeping the keeping temperature; annealing the synthetic quartz glass; and taking the synthetic quartz glass out of the heat treatment furnace. The process includes determining an annealing rate v [ C./h] of the annealing step based on a value of S/V [mm.sup.2/mm.sup.3], wherein S [mm.sup.2] is the surface area of the synthetic quartz glass as a parent material and V [mm.sup.3] is the volume thereof and a target birefringence Re [nm/cm] for the synthetic quartz glass after the annealing, and the annealing step is performed at the determined annealing rate v.

This chemically tempered glass is manufactured by preparing a slurry or paste including a salt solution of a second ion to undergo ion exchange with a first ion inside a glass, applying the slurry or the paste onto the surface of the glass to form a coating film, drying the coating film formed of the slurry or the paste on the surface of the glass, differently forming the distribution of the precipitation phase of a salt of the second ion on the surface of the glass, and heat-treating the glass on which the coating film is formed, to thereby form visual internal roughness which is provided between a first surface and a second surface of the glass, which face each other, to induce the diffuse reflection and/or scattering of light traveling through the first surface or the second surface.

A method for manufacturing a glass substrate includes: flattening a to-be-scribed region extending along a predetermined to-be-scribed line on a surface of a glass blank by irradiating the surface of the glass blank with a first laser beam along the to-be-scribed line; and forming a scribe line along the to-be-scribed line by irradiating the flattened to-be-scribed region with a second laser beam.