The invention relates to a method to produce a medical form body of lithium silicate glass ceramic. To increase its strength it is proposed that a surface compressive stress is created in a form body of lithium silicate glass, or containing lithium silicate glass, through the replacement of lithium ions by alkali metal ions of greater diameter. For this purpose the form body is covered with a paste that contains alkali metal.

A display cover is provided. The display cover includes a first glass and a second glass; a carbon material layer disposed between the first glass and the second glass, wherein the carbon material layer is formed by simultaneously applying a heat treatment process to an organic adhesive layer, the first glass, and the second glass to carbonize the organic adhesive layer. The structural strength of display cover can be strengthened by placing a carbon material layer between two glass layers to achieve a strong chemical bond between the thin carbon material layer disposed between the two glass layers and the two glass layers.

According to one embodiment, a method for thermally treating glass articles may include holding a glass article at a treatment temperature equal to an annealing temperature of the glass article 15 C. for a holding time greater than or equal to 5 minutes. Thereafter, the glass article may be cooled from the treatment temperature through a strain point of the glass article at a first cooling rate CR1 less than 0 C./min and greater than 20 C./min such that a density of the glass article is greater than or equal to 0.003 g/cc after cooling. The glass article is subsequently cooled from below the strain point at a second cooling rate CR.sub.2, wherein |CR.sub.2|>|CR.sub.1|.

According to one embodiment, a method for thermally treating glass articles may include holding a glass article at a treatment temperature equal to an annealing temperature of the glass article 15 C. for a holding time greater than or equal to 5 minutes. Thereafter, the glass article may be cooled from the treatment temperature through a strain point of the glass article at a first cooling rate CR1 less than 0 C./min and greater than 20 C./min such that a density of the glass article is greater than or equal to 0.003 g/cc after cooling. The glass article is subsequently cooled from below the strain point at a second cooling rate CR.sub.2, wherein |CR.sub.2|>|CR.sub.1|.

A drinking implement includes: a first opening; a lumen; a second opening fluidly coupled to the first opening and the lumen; and a wall including a glass and extending from the first opening to the second opening and surrounding the lumen. The wall has an inner surface facing toward the lumen and an outer surface facing away from the lumen. The wall has a first compressive stress layer extending from the inner surface to a first depth within the wall, a second compressive stress layer extending from the outer surface to a second depth within the wall, and a tensile stress layer disposed within the wall at a depth between the first compressive stress layer and the second compressive stress layer. The second depth is from 0.05% to 25% of a thickness of the wall.

A method and apparatus for manufacturing a quartz glass ingot of large cross-sectional area by continuous flame-fusion whereby on-line crack-free cutting of the ingot is ensured by using the internal heat of the ingot to permit equilibration of the internal and surface temperatures while passing through one or more annealing chambers, thus ensuring controlled cooling to temperature at which it is possible to cut the ingot with a water-cooled saw.

A method and apparatus for manufacturing a quartz glass ingot of large cross-sectional area by continuous flame-fusion whereby on-line crack-free cutting of the ingot is ensured by using the internal heat of the ingot to permit equilibration of the internal and surface temperatures while passing through one or more annealing chambers, thus ensuring controlled cooling to temperature at which it is possible to cut the ingot with a water-cooled saw.

Apparatus for shaping at least one glass sheet wherein a lower press ring and an upper press ring are configured to clamp a perimeter section of the glass sheet between the lower press ring and the upper press ring. The apparatus also includes an upper press at least partially disposed within the upper press ring and configured to shape at least a section of the glass sheet inside the perimeter section of the glass sheet, including forming by use of applied vacuum. The inner press may include openings that apply vacuum in selected areas of the inner press to vacuum form the ply within the selected areas. To control the ply on the upper press assembly, vacuum that is applied though passageways in the upper press ring to the gap between the upper press ring and the inner press is controlled through a seal in the gap. The upper press ring includes pivotal joints that increase adjustability of the forming surface of the upper press ring to the face surface of the inner press.

Apparatus for shaping at least one glass sheet wherein a lower press ring and an upper press ring are configured to clamp a perimeter section of the glass sheet between the lower press ring and the upper press ring. The apparatus also includes an upper press at least partially disposed within the upper press ring and configured to shape at least a section of the glass sheet inside the perimeter section of the glass sheet, including forming by use of applied vacuum. The inner press may include openings that apply vacuum in selected areas of the inner press to vacuum form the ply within the selected areas. To control the ply on the upper press assembly, vacuum that is applied though passageways in the upper press ring to the gap between the upper press ring and the inner press is controlled through a seal in the gap. The upper press ring includes pivotal joints that increase adjustability of the forming surface of the upper press ring to the face surface of the inner press.

A method of forming a dissolvable part of amorphous borate includes: preparing a mixture comprising one or more boron compounds and one or more alkali compounds, at least one of the one or more boron compounds and the one or more alkali compounds being hydrous; heating the mixture to a melting temperature for a predetermined time to melt the mixture and release water from the mixture to form an anhydrous boron compound that is moldable, wherein the amount of alkali compound being selected to achieve an alkali oxide content of between about 10 to 25%; with the anhydrous boron compound at a molding temperature, molding the anhydrous boron compound in a mold; and cooling the anhydrous boron compound to form a solid.