A method for producing bubble-free glasses is provided, in which a glass mixture that is arsenic-free, antimony-free and tin-free with the exception of any unavoidable raw material impurities and at least one sulfate compound as a refining agent are used. The glass mixture and refining agent are melted and primarily refined in a first region of a melting tank, an average melting temperature (T1) is set at T1>1580 C. and an average melt residence time (t1) is set at t1>2 hours. A secondary refinement is carried out in a second region, an average melting temperature (T2) is set at T2>1660 C. and an average melt residence time (t2) is set at t2>1 hour, and the proportion of the SO.sub.3 resulting from decomposition of the sulfate is reduced to less than 0.002 wt. %.

The present invention relates to a composite material, particularly a composite material for ceramic tiles, stone cladding, surface tops (e.g. worktops), and the like. The composite materials are typically derived from waste products. The composite materials of the present invention are formed from a glass component and a non-glass mineral component (e.g. ceramics and/or glaze). Generally the composite materials do not require any binders (especially synthetic binders) to hold the materials together. Therefore, the composite materials and products made therefrom are typically recyclable.

A sealing agent for ion transport membranes (ITMs) includes a composition having a glass powder and a ceramic powder. The ceramic powder can include Ba.sub.0.5Sr.sub.0.5Co.sub.0.8Fe.sub.0.2O.sub.3- (BSCF) or La.sub.2NiO.sub.4+ (LNO). The ceramic powder can be identical to the ceramic powder from which the ITM is made. The glass powder can include PYREX glass. The sealing agent can be in the form of a paste. The sealing agent can be used to attach an ion transport membrane to one or more support tubes. The sealing agent includes from about 10 wt. % to about 40 wt. % glass powder and from about 60 wt. % to about 90% wt. % (BSCF) ceramic powder.

A composition for ceramic substrates that includes a mixture of borosilicate glass powder and ceramic powder. The borosilicate glass powder contains 4% to 8% by weight B.sub.2O.sub.3, 38% to 44% by weight SiO.sub.2, 3% to 10% by weight Al.sub.2O.sub.3, and 40% to 48% by weight MO, where MO is at least one selected from CaO, MgO, and BaO. The mixing proportions of the borosilicate glass powder and the ceramic powder are 50% to 56% by weight the borosilicate glass powder and 50% to 44% by weight the ceramic powder. The ceramic powder has an average particle diameter D50 of 0.4 to 1.5 m.

A method of forming glass ceramic articles. The articles, in some embodiments, have a three dimensional shape. A frit mixture containing the glass ceramic in frit form and a glass frit are dispersed, in some embodiments, in a vehicle to create a slurry, which is then formed into a desired shape to make a green body. Forming may be accomplished by injection molding sinter forging, casting, casting and pressing, isostatically pressing, or the like. The green body is then fired at a high temperature to burn off the binder and fuse the glass ceramic and glass frit into a solid glass ceramic body. In some embodiments, the glass ceramic powder and glass frit material may be ion exchanged to achieve surface layers having high compressive stress, resulting in high damage resistance of the article.

A glass-ceramic that includes: 5 mol %Al.sub.2O.sub.340 mol %; 30 mol %B.sub.2O.sub.360 mol %; 10 mol %WO.sub.350 mol %; 0 mol %SnO.sub.25 mol %; and 1 mol %R.sub.2O30 mol %, wherein R.sub.2O is one or more of Li.sub.2O, Na.sub.2O, K.sub.2O, Rb.sub.2O, and Cs.sub.2O. Further, the glass-ceramic can be silica-free and, in some cases, can have a thickness from about 0.05 mm to about 0.5 mm and one or more of: (a) a total transmittance of less than or equal to 4% at ultraviolet (UV) wavelengths below 400 nm and (b) a total transmittance from about 0.5% to about 4% in the near-infrared (NIR) spectrum from 700 nm to 1500 nm.

A method of manufacturing a heat exchanger core from glass ceramic matrix composite includes placing one or more reinforcing fibers around one or more mandrels into a mold cavity. A glass matrix material infiltrates the one or more reinforcing fibers to produce an infiltrated core and the one or more mandrels is removed to create one or more passages passing through the infiltrated core.

A transparent article is described herein that includes: a substrate; and an optical film structure on the substrate having a thickness of from about 200 to 5000 nm. The optical film structure comprises a scratch-resistant layer, at least one low refractive index (RI), medium RI, and high RI layer, an inner structure disposed on the substrate, and an outer structure comprising alternating high and medium RI layers. Each medium RI layer comprises a refractive index from 1.55 to 1.9, each high RI layer comprises a refractive index greater than 1.80, each low RI layer comprises a refractive index from 1.35 to 1.7.

A wiring board that includes: a wiring conductor; a first dielectric layer around the wiring conductor and containing a first glass and a first ceramic filler; and a second dielectric layer interposed between the wiring conductor and the first dielectric layer, the second dielectric layer being in contact with the wiring conductor and the first dielectric layer, and the second dielectric layer containing a second glass and a second ceramic filler. A sintering temperature of the second glass contained in the second dielectric layer is higher than a sintering temperature of the wiring conductor, and a grain size of the second glass contained in the second dielectric layer is smaller than a grain size of the first glass contained in the first dielectric layer.

A glass-ceramic structure that includes first ceramic layers containing crystals and second ceramic layers containing crystals. The crystal content of the first ceramic layers is different from the crystal content of the second ceramic layers. The shortest distance in a thickness direction from a surface of the glass-ceramic structure to the second ceramic layer and the thickness of the second ceramic layer is 10. The crystals include at least one type selected from Al.sub.2O.sub.3, Zn.sub.2SiO.sub.4, ZnO, ZnAl.sub.2O.sub.4, BaAl.sub.2Si.sub.2O.sub.8, ZnTiO.sub.3, Al.sub.2TiO.sub.5, TiO.sub.2, Mg.sub.2SiO.sub.4, MgSiO.sub.3, and MgO. The percentage of a cross-sectional area of the crystals in the second ceramic layers relative to a cross-sectional area of the second ceramic layers is greater than a percentage of a cross-sectional area of the crystals in the first ceramic layers relative to a cross-sectional area of the first ceramic layers by a difference of 10 area % to 75 area %.