Thin glass elements with improved edge strength are provided—from a sheet glass element that has two opposite parallel faces and an edge connecting the faces. The sheet glass element has a thickness of at most 700 μm. At least a portion of the edge is defined by an edge surface portion that is convexly curved, so that at least one of the faces merges into the edge surface portion, wherein a curved arc of the edge surface portion has a length that is at least 1/30 of the thickness of the sheet glass element. In the region of the convex curvature, the edge surface portion has indentations in the form of furrows.

A borosilicate glass for a pharmaceutical container having high appearance quality, particularly a small number of air lines, and a glass tube for a pharmaceutical container are provided. The borosilicate glass for a pharmaceutical container contains, in mass %, from 70.0 to 78.0% of SiO.sub.2, from 5.0 to 8.0% of Al.sub.2O.sub.3, from 5.0 to 12.0% of B.sub.2O.sub.3, from 0 to 4.0% of CaO, from 0 to 4.0% of BaO, from 4.0 to 8.0% of Na.sub.2O, from 0 to 5.0% of K.sub.2O and from 0.001 to 1.0% of SnO.sub.2.

A method of of fining low-density submerged combustion glass includes introducing unfined molten glass produced in a submerged combustion melter into a fining chamber of a fining tank and, further, introducing additive particles into the fining chamber that comprise a glass reactant material and one or more fining agents. The one or more fining agents are released into the molten glass bath upon consumption of the additive particles in the molten glass bath to chemically fine the molten glass bath and the glass reactant material includes one or more materials that integrate into the molten glass bath upon melting. Additionally, the method includes discharging fined molten glass out of the fining chamber of the fining tank. The discharged fined molten glass has a volume percentage of gas bubbles that is less than the volume percentage of gas bubbles in the unfined molten glass introduced into the fining chamber.

A method for producing a glass article having high hydrolytic resistance is provided. A glass tube consisting of borosilicate glass and having an Al.sub.2O.sub.3 content of less than 1 weight-%, a ZrO.sub.2 content of 2-12 weight-%, and a glass transition temperature T.sub.g is reshaped into a glass article and is subsequently subjected to a thermal post-treatment. To reduce the alkali release of the glass article, the glass article is subjected to a treatment temperature of T.sub.B≥T.sub.g+5° K over a treatment time of t.sub.B≥5 min and is subsequently cooled during the thermal post-treatment.

Optical glass filters are provided that include a filter glass showing an optimized transmission spectrum which has a high transmission in the wave length range of 300 to 400 nm and a very low transmission in the visible wave length range. The glass has an especially high optical quality and is excellently suitable as an optical filter for generating UV light without a proportion of visible light. The optical glass filters include the components nickel oxide and cobalt oxide.

A method for forming a laminated glass article may include flowing a molten first glass composition having a first R.sub.2O concentration and a first fining agent with a first fining agent concentration. The method may also include flowing a molten second glass composition having a second R.sub.2O concentration less than the first R.sub.2O concentration of the first glass composition and a second fining agent with a second fining agent concentration that is greater than or equal to the first fining agent concentration of the first glass composition. The molten first glass composition may be contacted with the molten second glass composition to form an interface between the molten first glass composition and the molten second glass composition.

The present invention relates to a float glass substrate including an alkali-free glass, the float glass substrate having a Cl content of from 0.10 to 0.50 mass %, containing substantially no SnO.sub.2, and having a Pt content of, by mass, from 0.001 to 0.30 ppm. The float glass substrate may have a Rh content of, by mass, from 0.001 to 0.50 ppm.

The present applicationprovides transparent glass-ceramics of lithium aluminosilicate type, of β-quartz, the composition of which contains a low content of lithium, articles constituted at least in part by said glass-ceramics, precursor glasses for said glass-ceramics, and also a method of preparing said articles. Said glass-ceramics have a composition, expressed in percentages by weight of oxide, containing63% to 67.5% of SiO.sub.2; 18% to 21% of Al.sub.2O.sub.3; 2% to 2.9% of Li.sub.2O; 0 to 1.5% of MgO; 1% to 3.2% of ZnO; 0 to 4% of BaO; 0 to 4% of SrO; 0 to 2% of CaO; 2% to 5% of TiO.sub.2; 0 to 3% of ZrO.sub.2; 0 to 1% of Na.sub.2O; 0 to 1% of K.sub.2O; 0 to 5% of P.sub.2O.sub.5; with (0.74 MgO+0.19 BaO+0.29 SrO+0.53 CaO+0.48 Na.sub.2O+0.32 K.sub.2O)/Li.sub.2O<0.9; optionally up to 2% of at least one fining agent; and optionally up to 2% of at least one coloring agent.

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.

The present invention relates to the field of glass manufacturing, and discloses aluminoborosilicate glass, and a preparation method and an application thereof. Based on the total weight of components in the composition of the glass, the glass comprises: 33-60 wt % SiO.sub.2, 3-10 wt % Al.sub.2O.sub.3, 10-30 wt % B.sub.2O.sub.3, 1-15 wt % ZnO+TiO.sub.2+Sc.sub.2O.sub.3, and 7-27 wt % alkaline-earth oxide RO, wherein RO is at least one of MgO, CaO, SrO and BaO, and 0.001 wt %≤Sc.sub.2O.sub.3≤1 wt%. The aluminoborosilicate glass provided in the present invention has advantages including low density, high index of refraction, low thermal expansion coefficient, high thermostability, high flexibility, and easy bending, etc.