Abstract: This invention is directed to glasses especially suitable for use as envelopes in tungsten-halogen lamps, those glasses exhibiting liquidus temperatures no higher than 1125.degree. C., liquidus viscosities of at least 50,000 poises, coefficients of thermal expansion between about 42-46.times.10.sup.-7 /.degree.C., and consisting essentially, in weight percent on the oxide basis ofSiO.sub.2 --56-59Al.sub.2 O.sub.3 --16-17B.sub.2 O.sub.3 --4.5-5.25CaO--7.5-9.25MgO--5.5-6.

Abstract: The present invention is directed to glasses especially suitable as envelopes for tungsten-halogen lamps. The glasses exhibit strain points of at least about 670.degree. C., a coefficient of thermal expansion (0.degree.-300.degree. C.) of 42-45.times.10.sup.-7 /.degree.C. and can be readily melted and shaped utilizing conventional glass melting and high speed tube drawing processes. The glasses consist essentially, in weight percent, of______________________________________ SiO.sub.2 60.0 .+-. 1.5 Al.sub.2 O.sub.3 17.0 .+-. 1.0 B.sub.2 O.sub.3 5.0 .+-. 0.8 CaO 11.4 .+-. 0.8 MgO 7.5 .+-. 0.

Abstract: This invention is directed to the production of glasses having particular utility as envelopes for tungsten-halogen incandescent lamps because of their thermal endurance and capability of use at the high temperatures at which such lamps operate, coupled with their facility for being sealed to molybdenum. The glasses manifest a strain point in excess of 730.degree. C., a liquidus temperature less than 1200.degree. C., a viscosity at the liquidus of at least 40,000 poises, axial compression at room temperature not exceeding 350 PPM and axial tension or compression at 500.degree. C. not exceeding 150 PPM when sealed to molybdenum leads, and a coefficient of thermal expansion (0.degree.-300.degree. C.) less than 48.times.10.sup.-7 /.degree. C. Such glasses consist essentially, by weight on the oxide basis, of 61-65% SiO.sub.2, 14-17% Al.sub.2 O.sub.3, 8-15% CaO, and 6-9% SrO.

Abstract: The present invention is related to the fabrication of electronic devices wherein a thin film of silicon is deposited upon a substrate. More particularly, the invention is directed to such devices wherein the substrate therefor is an alkaline earth metal aluminosilicate glass consisting essentially, by weight, of about 55-75% SiO.sub.2, 5-25% Al.sub.2 O.sub.3, and at least one alkaline earth metal oxide selected from the group consisting of 9-15% CaO, 14-20% SrO, 18-26% BaO, and mixtures thereof in a total amount equivalent on a molar basis to 9-15% CaO.

Abstract: This invention relates to a method for forming glass articles having essentially defect-free surfaces which can be equivalent in smoothness to that achieved in a polishing operation, and which can demonstrate mechanical strength superior to that exhibited by glass articles produced via conventional glass-forming techniques.The method contemplates melting two different glass compositions, one of which is highly soluble in a given solvent and the second of which is relatively insoluble in the same solvent; the molten glasses are simultaneously brought together while in the fluid state to form a laminated glass body wherein the insoluble glass is essentially completely enveloped within the soluble glass; the laminae are fused together at a temperature where the melts are in fluid form to provide an interface therebetween which is free from defects; the laminated article is cooled; and the soluble outer glass layer is dissolved away in an appropriate solvent.

Abstract: A gauge for exhibiting the liquid level in a container of alkaline liquid, for example a boiler or radiator gauge, is disclosed. The gauge includes a glass component composed at least in part of a glass consisting essentially of 20-50% SiO.sub.2, 3-40% Y.sub.2 O.sub.3, 5-25% of a divalent metal oxide and 0-30% Al.sub.2 O.sub.3. Other features of the invention include use of an yttrium concentrate in producing the glass and a composite glass component wherein only a facing portion is composed of the yttrium glass.

Abstract: This invention is concerned with spontaneous opal glasses wherein sodium fluoride (NaF) and strontium fluoride (SrF.sub.2) constitute the predominant opacifying phases. More specifically, the opal glasses of the instant invention have compositions within the Na.sub.2 O--SrO--Al.sub.2 O.sub.3 --SiO.sub.2 --F field and exhibit a dense white appearance, a softening point above 755.degree. C., a strain point in excess of 500.degree. C., a coefficient of thermal expansion (0.degree.-300.degree. C.) in excess of 65.degree. .times. 10.sup.-7 /.degree. C., and satisfactory resistance to weathering and dishwasher environments.

Abstract: This invention relates to the production of a composite article consisting of an opal glass body exhibiting a dense, milky-white appearance coated with an adherent enamel demonstrating high gloss and exceptional chemical durability. More specifically, the opal glasses of the present invention have compositions within the Na.sub.2 O-Al.sub.2 O.sub.3 -SiO.sub.2 -F system and demonstrate a softening point in excess of 760.degree. C., a strain point in excess of 490.degree. C., and a coefficient of thermal expansion (0.degree.-300.degree. C.) of about 66-75 .times. 10.sup..sup.-7 /.degree. C. The enamels of the instant invention have flux compositions within the Li.sub.2 O-B.sub.2 O.sub.3 -TiO.sub.2 -ZrO.sub.2 -PbO-SiO.sub.2 system, will fire to a high gloss in less than about 10 minutes at temperatures below about 720.degree. C., will exhibit coefficients of thermal expansion (25.degree.-300.degree. C.

Abstract: An infrared detection system is described that embodies an improved glass window for transmitting infrared radiation to a heat sensitive detection element in the system. The window is produced from a glass consisting essentially, in percent by weight on an oxide basis, of 25-50% GeO.sub.2, 10-50% La.sub.2 O.sub.3 5-50% Ta.sub.2 O.sub.5 and 2-20% ZnO. Such glasses are hard and abrasion resistant, have moderate coefficients of thermal expansion and have a substantial transmission for infrared radiation in the wavelength range of five to six microns.

Abstract: The invention relates to glasses especially suitable for the envelope of a tungsten-bromine incandescent lamp and which can be sealed directly to molybdenum. Such glasses exhibit strain points in excess of 700.degree.C., a viscosity at the liquidus, of at least 100,000 poises, and a coefficient of thermal expansion (0.degree.-300.degree.C.) between about 48-55 .times. 10.sup.-.sup.7 /.degree.C. More particularly, such glasses consist essentially, by weight on the oxide basis, of about 58-63% SiO.sub.2, 13-16% Al.sub.2 O.sub.3, 14-21% CaO, 0-5% MgO, and 0-7% BaO, the total CaO + MgO + BaO constituting at least about 19%.

Abstract: A composite glass article is disclosed that is composed of a TiO.sub.2 --Al.sub.2 O.sub.3 --SiO.sub.2 glass core portion encompassed within a compressively stressed, vitreous silica-type glass exterior portion. The composite is strengthened by heat treatment within the ranges of 600.degree.C. to 900.degree.C. to effect a non-reversible contraction of the core glass at temperatures below the lowest glass strain point.