Photosensitive lithium zinc aluminosilicate glasses that can be selectively irradiated and cerammed to provide patterned regions of glass and lithium-based glass ceramic, and composite glass articles made from such glasses and glass ceramics are provided. The lithium zinc aluminosilicate glass can be negatively photosensitive or positively photosensitive to radiation having a wavelength in a range from about 248 nm to about 360 nm.

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 that includes a housing, a skimmer, and a dissolvable fining material component disposed directly beneath the skimmer.

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 that includes a housing, a skimmer, and a dissolvable fining material component disposed directly beneath the skimmer.

The invention relates to the field of glass manufacturing, and discloses non-alkali aluminum silicate glass and a preparation method as well as application thereof. A glass melt of the non-alkali aluminum silicate glass at 1600° C. has a resistivity of 200 Ω.Math.cm or less; a temperature T.sub.35000 corresponding to 35000 P viscosity is 1250° C. or more; an annealing point corresponding to 1013 P viscosity is 790° C. or more, based on a total molar weight of the non-alkali aluminum silicate glass, the non-alkali aluminum silicate glass comprises, by oxide, 69-73 mol % of SiO.sub.2, 11-15 mol % of Al.sub.2O.sub.3, 0-2 mol % of B.sub.2O.sub.3, 2-8 mol % of MgO, 2-8 mol % of CaO, 0-3 mol % of SrO, 3-10 mol % of BaO, 0.1-2 mol % of ZnO, 0.02-0.7 mol % of RE.sub.2O.sub.3, 0.01-0.5 mol % of Se.sub.2O.sub.3 and R.sub.2O, less than 0.05 mol %, wherein RE represents rare earth elements, and R represents alkali metals.

A glass material with a low dielectric constant and a low fiberizing temperature includes silicon dioxide, boron trioxide, aluminum oxide, calcium oxide, phosphorus pentoxide and zinc oxide. The silicon dioxide makes up 45%-52% by weight of the glass material. The boron trioxide makes up 25%-30% by weight of the glass material. The aluminum oxide makes up 10%-14% by weight of the glass material. The calcium oxide makes up 1%-4% by weight of the glass material. The phosphorus pentoxide makes up 0-3% by weight of the glass material. The zinc oxide makes up 1%-5% by weight of the glass material. The reduced silicon dioxide content and calcium oxide content and addition of phosphorus pentoxide and zinc oxide in the glass material lower the dielectric constant and fiberizing temperature of the glass material.

A glass material with a low dielectric constant and a low fiberizing temperature includes silicon dioxide, boron trioxide, aluminum oxide, calcium oxide, phosphorus pentoxide and zinc oxide. The silicon dioxide makes up 45%-52% by weight of the glass material. The boron trioxide makes up 25%-30% by weight of the glass material. The aluminum oxide makes up 10%-14% by weight of the glass material. The calcium oxide makes up 1%-4% by weight of the glass material. The phosphorus pentoxide makes up 0-3% by weight of the glass material. The zinc oxide makes up 1%-5% by weight of the glass material. The reduced silicon dioxide content and calcium oxide content and addition of phosphorus pentoxide and zinc oxide in the glass material lower the dielectric constant and fiberizing temperature of the glass material.

A glass-ceramic comprising, in weight percent on an oxide basis, of 50 to 70% SiO.sub.2, 0 to 20% Al.sub.2O.sub.3, 12 to 23% MgO, 0 to 4% Li.sub.2O, 0 to 10% Na.sub.2O, 0 to 10% K.sub.2O, 0 to 5% ZrO.sub.2, and 2 to 12% F, wherein the predominant crystalline phase of said glass-ceramic is a trisilicic mica, a tetrasilicic mica, or a mica solid solution between trisilicic and tetrasilicic, and wherein the total of Na.sub.2O+Li.sub.2O is at least 2 wt. %; wherein the glass-ceramic can be ion-exchanged.

A chemically strengthened bioactive glass-ceramic composition as defined herein. Also disclosed are methods of making and using the disclosed compositions.

A chemically strengthened bioactive glass-ceramic composition as defined herein. Also disclosed are methods of making and using the disclosed compositions.

Coated glass or glass ceramic substrates having high temperature resistance, high strength, and a low coefficient of thermal expansion. The coating includes pores, is fluid-tight and suitable for coating a temperature-resistant, high-strength glass or glass ceramic substrate with a low coefficient of thermal expansion, and to a method for producing such a coated substrate.