A low infrared absorbing lithium glass includes FeO in the range of 0.0005-0.015 wt %, more preferably 0.001-0.010 wt %, and a redox ratio in the range of 0.005-0.15, more preferably in the range of 0.005-010. The glass can be chemically tempered and used to provide a ballistic viewing cover for night vision goggles or scope. A method is provided to change a glass making process from making a high infrared absorbing lithium glass having FeO in the range of 0.02 to 0.04 wt % and a redox ratio in the range of 0.2 to 0.4 to the low infrared absorbing lithium glass by adding additional oxidizers to the batch materials. A second method is provided to change a glass making process from making a low infrared absorbing lithium glass to the high infrared absorbing lithium glass by adding additional reducers to the batch material. In one embodiment of the invention the oxidizer is CeO.sub.2. An embodiment of the invention covers a glass made according to the method.

The present invention provides crystallized glass of three-dimensional shape for easily producing chemically strengthened glass of three-dimensional shape that resists damage and has exceptional transparency. This crystallized glass of three-dimensional shape:

contains crystals; has light transmittance in terms of a thickness of 0.8 mm of 80% or higher; and contains 45-74% SiO.sub.2, 1-30% Al.sub.2O.sub.3, 1-25% Li.sub.2O, 0-10% Na.sub.2O, 0-5% K.sub.2O, a total of 0-15% of SnO.sub.2 and/or ZrO.sub.2, and 0-12% P.sub.2O.sub.5, these amounts expressing the oxide-based mass percentage.

A low infrared absorbing lithium glass includes FeO in the range of 0.0005-0.015 wt %, more preferably 0.001-0.010 wt %, and a redox ratio in the range of 0.005-0.15, more preferably in the range of 0.005-010. The glass can be chemically tempered and used to provide a ballistic viewing cover for night vision goggles or scope. A method is provided to change a glass making process from making a high infrared absorbing lithium glass having FeO in the range of 0.02 to 0.04 wt % and a redox ratio in the range of 0.2 to 0.4 to the low infrared absorbing lithium glass by adding additional oxidizers to the batch materials. A second method is provided to change a glass making process from making a low infrared absorbing lithium glass to the high infrared absorbing lithium glass by adding additional reducers to the batch material. In one embodiment of the invention the oxidizer is CeO.sub.2. An embodiment of the invention covers a glass made according to the method.

Embodiments relate to a green glass composition, which can reduce the cooling load of a building and a vehicle by effectively lowering solar heat ray and ultraviolet ray transmittance while ensuring a high visible light transmittance suitable for window glass without using a coloring agent such as Ce, Co and Cr, and also has excellent bubble quality; green glass manufactured therefrom; and a method for manufacturing green glass. According to at least one embodiment, there is provided a green glass composition including 0.65-1.3 wt % of Fe.sub.2O.sub.3, 0.1-0.4 wt % of TiO.sub.2, and 0.05-0.20 wt % of SO.sub.3, based on 100 wt % of a soda lime mother glass composition, wherein an oxidation-reduction ratio of Fe.sub.2O.sub.3 is 0.22 to 0.38.

A method of producing flint glass using submerged combustion melting involves introducing a vitrifiable feed material into a glass melt contained within a submerged combustion melter. The vitrifiable feed material is formulated to provide the glass melt with a glass chemical composition suitable for producing flint glass articles. To that end, the glass melt comprises a total iron content expressed as Fe.sub.2O.sub.3 in an amount ranging from 0.04 wt % to 0.06 wt % and also has a redox ratio that ranges from 0.1 to 0.4, and the vitrifiable feed material further includes between 0.008 wt % and 0.016 wt % of selenium or between 0.1 wt % and 0.2 wt % of manganese oxide in order to achieve an appropriate content of selenium or manganese oxide in the glass melt.

A composition for glass, alkaline earth aluminosilicate glass, and a preparation method therefor and applications thereof. Based on the total number of moles of each component and the counting of oxides, the composition contains 68-73 mol % of SiO.sub.2, 11.5-15 mol % of Al.sub.2O.sub.3, 2-6 mol % of MgO, 2.5-7.5 mol % of CaO, 0-3 mol % of SrO, 2-7 mol % of BaO, 0-4 mol % of ZnO and 0.05-1.5 mol % of TiO.sub.2. The glass has a high strain point, a high Young's modulus, a high specific modulus, a high Vickers hardness, high chemical stability, a high refractive index and high glass formation stability, and has a lower forming temperature, a lower melting temperature, a lower thermal expansion coefficient, a lower surface tension, a lower density, and low glass manufacturing difficulty.

In a process for manufacturing glass, a mixture of solid glass-forming materials may be melted by application of heat from one or more submerged combustion burners to produce a volume of unrefined molten glass comprising, by volume, 20% to 40% gas bubbles. A refining agent may be introduced into the unrefined molten glass to promote gas bubble removal from the molten glass. The unrefined molten glass including the refining agent may be heated at a temperature in the range of 1200° C. to 1500° C. to produce a volume of refined molten glass. The refined molten glass may comprise, by volume, fewer gas bubbles than the unrefined molten glass. A colorant material may be introduced into the refined molten glass to produce a volume of molten glass having a final desired color.

A method of fining low-density submerged combustion glass is disclosed. The method involves introducing unfined molten glass produced in a submerged combustion melter into a fining chamber of a downstream fining tank. Additionally, additive particles are also introduced into the fining chamber to release one or more fining agents into the molten glass bath contained in the fining chamber to accelerate the removal of bubbles from the molten glass bath. The fining of the molten glass bath as assisted by the one or more fining agents allows for fined glass to be discharged from the fining tank that has fewer bubbles and a greater density than that of the unfined molten glass introduced into the fining tank. Additive particles that include a physical mixture of a glass reactant material and the fining agent(s) are also disclosed.

A method of fining glass is disclosed that includes flowing a molten glass bath through a fining chamber. The molten glass bath has an undercurrent that flows beneath a skimmer that is partially submerged in the molten glass bath. One or more fining agents are introduced into the undercurrent of the molten glass bath directly beneath the skimmer from a dissolvable fining material component. In this way, the fining agent(s) may selectively target the gas bubbles drawn under the skimmer within the undercurrent of the molten glass for removal. The method may be employed to fine molten gas produced in a submerged combustion melter. A fining vessel for fining molten glass is also disclosed.

A method of producing and fining glass includes monitoring a temperature of a molten glass bath contained within a fining chamber of a fining vessel and, based on the monitored temperature, controlling an amount of a sulfate chemical fining agent added into a glass melt contained within an interior reaction chamber of an upstream submerged combustion melter that feeds the fining vessel. The temperature of the molten glass bath may be determined within a temperature indication zone that encompasses a subsurface portion of the molten glass bath that lies adjacent to a floor of a housing of the fining vessel. By monitoring the temperature of the molten glass bath and controlling the amount of the sulfate chemical fining agent added to the glass melt of the submerged combustion melter, the wasteful use of the sulfate chemical fining agent can be minimized and the fining process rendered more efficient.