Abstract:
The present invention relates to a cover glass for a display, which is a glass plate having a first main surface and a second main surface. The cover glass contains, as represented by mol percentage based on oxides, from 50 to 75% of SiO2, from 5 to 20% of Al2O3, from 2 to 20% of Na2O, from 0 to 6% of K2O, from 0 to 15% of MgO, from 0 to 10% of a total amount (CaO+SrO+BaO) of CaO, SrO and BaO, from 0 to 5% of a total amount (ZrO2+TiO2) of ZrO2 and TiO2, from 0 to 10% of B2O3, and from 0 to 20% of Li2O. The cover glass has a ream minimum distance of 100 mm or more and 1,000 mm or less, and a ream period of 1 mm or more and 30 mm or less.
Abstract:
The present invention provides for synthesizing high optical quality multicomponent chalcogenide glasses without refractive index perturbations due to striae, phase separation or crystal formation using a two-zone furnace and multiple fining steps. The top and bottom zones are initially heated to the same temperature, and then a temperature gradient is created between the top zone and the bottom zone. The fining and cooling phase is divided into multiple steps with multiple temperature holds.
Abstract:
A vacuum melting furnace for infrared glass, includes an upper furnace body and a lower furnace body that can be connected with each other or isolated from each other. Vacuum melting of the infrared glass is achieved in the upper furnace body wherein the influence of water in the environment is eliminated. The vacuum negative pressure environments can promote separation of hydroxyl in the structure, which achieves removing of hydroxyl in the glass, and then discharging of the molten infrared glass is conducted at atmospheric pressure in the lower furnace body. By using the vacuum melting furnace for infrared glass, infrared glass with good spectrum transmission performance can be obtained with improved property stability and optical homogeneity, which facilitates the preparation and molding of large sized and special-shaped infrared glass products.
Abstract:
Methods for producing glass articles from glass melts are provided that include continuously introducing the glass melt into a stirrer vessel, stirring the glass melt in the stirrer vessel by at least one blade stirrer, continuously discharging the glass melt from the stirrer vessel, and shaping the glass melt to obtain the glass article. In some embodiments, the stirring is sufficient to draw the glass melt located at a surface of the stirrer vessel into the stirrer vessel so that a formation of a surface layer of the glass melt with a different composition from the composition of the glass melt introduced is prevented or at least minimized. In other embodiments, the stirring is sufficient so that the glass melt which is located at a surface in the stirrer vessel is not drawn into the stirrer vessel or is drawn in only insubstantially.
Abstract:
A precious metal structure which has an internal gas permeable membrane is described herein for a glass manufacturing vessel configured to have molten glass flow therein. The internal gas permeable membrane can be supplied with an atmosphere of gas (or gases) to control the flux of hydrogen into our out of the molten glass or otherwise improve the production of the molten glass. In this manner, the undesirable detrimental reactions that can occur at the interface of the molten glass and precious metal interface which can cause defects in the molten glass such as bubbles or solid inclusions can be stopped or at least substantially reduced.
Abstract:
An apparatus for melting and refining a silica-based glass composition includes a vertical first reaction chamber having an input adjacent to a lower end for receiving glass-forming components. The glass-forming components are heated to elevated temperature during upward flow through the vertical first reaction chamber to form a glass precursor melt adjacent to an upper end of the vertical first reaction chamber. A vertical second reaction chamber has an input adjacent to an upper end and an output adjacent to a lower end for delivering glass melt. A cross passage connects the upper end of the vertical first reaction chamber to the upper end of the vertical second reaction chamber such that the precursor melt flows from the vertical first reaction chamber through the cross passage and then through the vertical second reaction chamber to homogenize the precursor melt. Vacuum preferably is applied to the cross passage both to assist upward flow through the vertical first reaction chamber, and to assist refining of the precursor melt during such upward flow and during flow through the cross passage.
Abstract:
The present invention is directed toward a method of reducing contamination of a glass melt in a stirring apparatus by an oxide material. The oxide material, such as platinum oxide, may be volatilized by the high temperature of the glass melt, and then condense on the inside surfaces of a stirring vessel, particularly the stirrer shaft and surrounding surfaces of the stirring vessel cover. A build-up of condensed oxide material may then be dislodged and fall back into the glass melt. Accordingly, an apparatus and method is provided that includes a heating element disposed adjacent an annular gap between the stirring vessel cover and the stirrer shaft. The heating element heats a surface of the stirring vessel cover bounding the annular gap and prevents condensation of volatile oxides that may flow through the annular gap.
Abstract:
In the formation of sheet material from molten glass, molten glass is formed in a melting furnace and transported through a precious metal delivery system to the forming apparatus. Disclosed herein is a method to mitigate carbon contamination of individual components of the precious metal delivery system prior to and/or during their use. The method involves positioning an oxygen generating material within portions of a precious metal component, and may comprise one or more heat treating steps of the component in an oxygen-containing atmosphere.
Abstract:
In the formation of sheet material from molten glass, molten glass is formed in a melting furnace and transported through a precious metal delivery system to the forming apparatus. Disclosed herein is a method to eliminate carbon-containing contamination of individual components of the precious metal delivery system prior to their installation and use. The method comprises one or more heat treating steps in an oxygen-containing atmosphere prior to and/or during assembly of the component.
Abstract:
The device for homogenizing a glass melt has at least one stirring device, which includes a rotatable stirrer shaft (10) and stirrer paddles (11, 11′, 11″). The stirrer paddles are arranged at intervals from each other along the stirrer shaft to produce an essentially axially oriented conveying effect on the glass melt. To improve homogenization while simultaneously saving on noble metal material, the stirrer paddles (11, 11′, 11″) are each provided with a built-in element (11E). The built-in element (11E) has an edge (11K), which extends from the stirrer shaft (10) in a radial direction (R) along a rear paddle area (11B) with an edge length which is less by a specified distance (X) than the length (L) of the paddle area (11B) in a radial direction (R). These built-in elements provide a marked reduction in bubble formation.