Provided is a glass fiber-reinforced resin molded article including low dielectric constant and particularly low dielectric loss tangent, in a high-frequency region of 10 GHz or more. The glass fiber-reinforced resin molded article contains glass fiber in the range of 10 to 90% by mass and a resin in the range of 90 to 10% by mass with respect to the. total amount of the glass fiber-reinforced resin molded article. The glass fiber includes a composition including 52.0 to 59.5% by mass of SiO.sub.2, 17.5 to 25.5% by mass of B.sub.2O.sub.3, 9.0 to 14.0% by mass of Al.sub.2O.sub.3, 0.5 to 6.0% by mass of SrO, 1.0 to 5.0% by mass of MgO, 1.0 to 5.0% by mass of CaO, and 0.1 to 2.5% by mass of F.sub.2 and Cl.sub.2 with respect to the total amount of the glass fiber, and a number average fiber length is 1 to 10000 μm.

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 glass material with low viscosity and a low bubble content attributable to a low weight percentage of silicon dioxide includes boron trioxide (B.sub.2O.sub.3), magnesium oxide (MgO), aluminum oxide (Al.sub.2O.sub.3), and calcium oxide (CaO) in addition to silicon dioxide (SiO.sub.2); wherein Silicon dioxide (SiO.sub.2) constitutes 45%-51% by weight of the glass material, boron trioxide (B.sub.2O.sub.3) 25%-35%, magnesium oxide (MgO) 0.01%-2%, aluminum oxide (Al.sub.2O.sub.3) 10%-14.5%, and calcium oxide (CaO) 4%-10%. As the silicon dioxide (SiO.sub.2) content is lower than in the prior art, the glass material has lower viscosity, and hence a lower bubble content, than in the prior art, and this allows products made of the glass material to have a higher yield than products made of the conventional glass.

A glass material with low viscosity and a low bubble content attributable to a low weight percentage of silicon dioxide includes boron trioxide (B.sub.2O.sub.3), magnesium oxide (MgO), aluminum oxide (Al.sub.2O.sub.3), and calcium oxide (CaO) in addition to silicon dioxide (SiO.sub.2); wherein Silicon dioxide (SiO.sub.2) constitutes 45%-51% by weight of the glass material, boron trioxide (B.sub.2O.sub.3) 25%-35%, magnesium oxide (MgO) 0.01%-2%, aluminum oxide (Al.sub.2O.sub.3) 10%-14.5%, and calcium oxide (CaO) 4%-10%. As the silicon dioxide (SiO.sub.2) content is lower than in the prior art, the glass material has lower viscosity, and hence a lower bubble content, than in the prior art, and this allows products made of the glass material to have a higher yield than products made of the conventional glass.

Glass ceramics having SiO.sub.2 as main crystal phase and precursors thereof are described which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

Glass ceramics having SiO.sub.2 as main crystal phase and precursors thereof are described which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

A ground coat enamel composition for production of an adhesion promoter layer between steel and at least one cover coat enamel for production of an enamel-based coating that is highly corrosion-resistant with respect to mechanical, thermal and chemical effects. The ground coat enamel composition includes boron oxide (B.sub.2O.sub.3) and alkali metal oxide(s), especially Li.sub.2O, Na.sub.2O and/or K.sub.2O, in percentage proportions by weight: a first main constituent, SiO.sub.2 from 35-70%, preferably 40-65%, and, as a second main constituent, from Fe.sub.2O.sub.3 5-28%, preferably in the range from 7-23% and particularly 8%-15% by weight. Also disclosed is a ground coat enamel layer produced from such a ground coat enamel composition. A highly corrosion-resistant article having such a ground coat enamel layer. A method for producing such a ground coat enamel layer and also a method for producing a highly corrosion-resistant article using such a ground coat enamel composition.

A method of producing glass using submerged combustion melting includes supplying a combustible gas mixture to one or more submerged burners of a submerged combustion melter, combusting the combustible gas mixture supplied to the submerged burner(s) to produce combustion products, and discharging the combustion products from the submerged burner(s) directly into a glass melt contained within the submerged combustion melter to agitate and heat the glass melt. The glass melt is comprised of soda-lime-silica glass and has a redox ratio. Additionally, the disclosed method involves controlling one or more operating conditions of the submerged combustion melter selected from (1) an oxygen-to-fuel ratio of the combustible gas mixture supplied to each of the submerged burners, (2) a residence time of the glass melt, and (3) a gas flux through the glass melt.

A method of producing glass using submerged combustion melting includes supplying a combustible gas mixture to one or more submerged burners of a submerged combustion melter, combusting the combustible gas mixture supplied to the submerged burner(s) to produce combustion products, and discharging the combustion products from the submerged burner(s) directly into a glass melt contained within the submerged combustion melter to agitate and heat the glass melt. The glass melt is comprised of soda-lime-silica glass and has a redox ratio. Additionally, the disclosed method involves controlling one or more operating conditions of the submerged combustion melter selected from (1) an oxygen-to-fuel ratio of the combustible gas mixture supplied to each of the submerged burners, (2) a residence time of the glass melt, and (3) a gas flux through the glass melt.

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.