Abstract: The glasses used for making rigid disk substrates have the following composition (in % by weight based on oxides): SiO2, 40 to 50.8; Al2O3, 5 to 20; B2O3, 0 to 5; Li2O, 0 to 10; Na2O, 0 to 12, with the proviso that Li2O+Na2O, 5 to 12; K2O, 0 to 5; MgO, 0 to 20; CaO, 0 to 6, with the proviso that MgO+CaO, 4 to 20; SrO+BaO, 0 to 10; ZrO2, 0 to 5; TiO2,0 to 5; CeO2, 0 to 1; La2O3, 0 to 10; Fe2O3, 0 to 10; Nb2O5, 0 to 10; V2O5, 0 to 15, with the proviso that TiO2+ZrO2+La2O3+Fe2O3+Nb2O5+V2O5≧18.7; As2O3+Sb2O3+F. 0,1 to 1. These glasses also fulfill the following inequality formulae (1): (E/&rgr;)·+3,500 R>38.5 and 1000 R>1  (1), wherein R represents the relaxation rate of the glass and E/&rgr; represents specific elasticity modulus of the glass measured in GPA*cm3/g.

Abstract: The invention relates to a barium-free, X-ray-opaque dental glass, to a dental glass/polymer composite comprising the glass, and to the use thereof as dental filling, where the dental glass has the following composition (in % by weight): SiO2 20-45, Al2O3 5-35, B2O3 1-10, Na2O 1-10, K2O 0-8, Cs2O 0-8, sum all alkali metal oxides 1-15, CaO 0-8, SrO 0-27, ZnO 2-20, ZrO2 2-10, P2O5 0-10, La2O3 0-10, F 2-20, the total content of B2O3, ZnO, ZrO2 and La2O3 is >20% by weight, and the refractive index nd of the dental glass is in the range from 1.47 to 1.70.

Abstract: A glass for a substrate consisting essentially of: SiO2 45 to 65 wt %, Al2O3 6 to 20 wt %, B2O3 0.5 to 6 wt %, MgO 2 to 5 wt %, CaO 1 to 10 wt %, SrO 0 to 6.5 wt %, BaO 0 to 2 wt %, MgO + CaO + SrO + BaO 10 to 17 wt %, ZrO2 0 to 7 wt %, and Na2O + K2O 7 to 15 wt %.

Abstract: An apatite glass ceramic is described which is characterized by good chemical stability, a low expansion coefficient and high translucence, and is particularly suitable, by itself or together with glasses or other glass ceramics, as a veneering material for ceramic dental restorations.

Abstract: The present invention provides an oxide glass capable of exhibiting a long lasting afterglow and photostimulated phosphorescence, can be used not only as a material for confirming an infrared laser or controlling an optical axis, but also as a material for recording or reproducing of &ggr;-rays, X-rays or UV-rays images and further can be used as an optical recording material of such a type that can be read. This glass material is represented, in term of atoms for making up the glass, by the following chemical composition (mol %): GeO2 21 to 80% ZnO 0 to 50% Ga2O2 0 to 55% (ZnO + Ga2O3 = 3 to 55%) Tb2O3 0 to 10% MnO 0 to 2% (Tb2O3 + MnO = 0.01 to 10%) R2O 0 to 45% (R: at least one atom selected from Li, Na, K and Cs) R′O 0 to 40% (R′: at least one atom selected from Mg, Ca, Sr and Ba) R2O + R′O 0.

Abstract: A plate glass containing B2O3, having a total content of Li2O, Na2O and K2O of from 0 to 13 mol %, a content of BaO of from 0 to 0.8 mol % and a content of SiO2 of from 50 to 75 mol %, and having an average linear thermal expansion coefficient of from 75×10−7 to 120×10−7/° C. in a range of from 50 to 350° C., a strain point of at least 550° C., a density of at most 2.65 g/cm3 at 20° C. and an oxygen atom density of from 7.2×10−2 to 9.0×10−2 mol/cm3 at 20° C.

Abstract: The object of the present invention is brown solar glasses, absorbing UV or IR radiation, as well as solar ophthalmic lenses in said glasses. Said glasses have the following composition, expressed in percentages by weight: SiO2: 64-71; B2O3: 2-8; Al2O3: 0-4; ZrO2: 0-2; Li2O: 0-4; Na2O: 6-10; K2O: 7-16; CaO: 0-5.5; ZnO: 0-5.5; TiO2; 0-2; Fe2O3: 3-9; Co3O4: 0-0.030; NiO: 0-0.2; SeO2: 0.0030-0.1; As2O3: 0-0.1; Sb2O3: 0-0.1; SnO2: 0-0.1; Cl: 0-2; Br: 0-2; F: 0-2.

Abstract: A graded index lens is obtained by treating a raw glass material having a rod shape by ion exchange using silver to form a refractive index distribution in the radial direction of the rod, wherein the raw glass material comprises a glass composition of the following components:

Abstract: A lead-free glass, which is suitable for use as imitation lead crystal tableware and decorative crystal glassware, has a chemical composition as a percentage by weight within the following range: silica 50-58 zirconium oxide 0-5 potash (K2O) 0-13, e.g. 0-12 yttrium oxide 0-5 soda (Na2O) 0-9 alumina 0-3 lithium oxide 0-4 tin oxide 0-5 calcium oxide 0-3 lanthanum oxide 0-9 magnesium oxide 0-4 niobium oxide 0-9 boric anhydride (B2O3) 0-2 bismuth oxide 0-13, e.g. 0-12 zinc oxide 16-30 germanium oxide 0-5 barium oxide 0-13, e.g. 0-12 antimony oxide 0-1 titanium oxide 0-6.

Abstract: A dielectric layer for use in a magneto-optic storage medium contains a compound glass of SiO2—MO2, SiO2—M2O3, or SiO2—M2O5 and combinations thereof where M is selected from Zr, Ti, Al, Nb, Y, Sn, In, Ta and Sb.

Abstract: A borosilicate glass having properties that enable it to be drawn as microsheets for use as a solar cell cover glass, and a solar cell having such microsheet as a cover glass, the glass having a composition consisting essentially of, expressed in terms of weight percent on an oxide basis: SiO2 59-69 ZnO 6.5-8.5 B2O3 8.5-14  CeO2 0.25-3   Al2O3   2-2.5 TiO2 0-1 Na2O  5.5-12.5 CeO2 + TiO2 0.5-4   K2O 0-8 Sb2O3    0-0.5.

Abstract: The zirconium-containing and lithium-containing borosilicate glasses have a higher resistance to chemical attack and have the following composition (in % by weight on an oxide basis): SiO2, 71 to <73%; B2O3, 7 to 10%; Al2O3, 6 to 9%; Li2O, 0.5 to 2%; Na2O, 0 to 10%; K2O, 0 to 10%; MgO, 0 to 2%; CaO, 0 to 3%; SrO, 0 to 3%; BaO, 0 to 3%; ZnO, 0 to 3%; ZrO2, 0.8 to 3%; CeO2, 0 to 1%, and a refining agent in an amount suitable for refining, as needed, with the proviso that a total amount of Li2O+Na2O+K2O is from 0.5 to 10.5%, and with the proviso that a total amount of MgO+CaO+SrO+BaO+ZnO is from 0 to 3%. These borosilicate glasses with their thermal expansion coefficients &agr;20/300 between 5.2 and 5.7×10−6/K are especially suitable for sealing glasses for Fe—Co—Ni alloys.

Abstract: An apatite glass ceramic is described which is characterized by good chemical stability, a low expansion coefficient and high translucence, and is particularly suitable, by itself or together with glasses or other glass ceramics, as a veneering material for ceramic dental restorations.

Abstract: Provided is a porcelain which is suitable as a dental porcelain capable of being fired on a ceramics core and has a low firing temperature and a low thermal expansion coefficient and which is excellent in a chemical durability. The above dental porcelain comprises glass containing silicon oxide, aluminum oxide, boron oxide, zinc oxide, sodium oxide and lithium oxide as principal components. The contents of these respective components in the above glass are 57 to 65% by weight of SiO2, 8 to 18% by weight of Al2O3, 15 to 25% by weight of B2O3, 0.1 to 2% by weight of ZnO, 3 to 7% by weight of Na2O and 2 to 8% by weight of Li2O respectively in terms of a percent by weight based on the total of the respective components when the respective components are reduced to SiO2, Al2O3, B2O3, ZnO, Na2O and Li2O respectively. The particularly preferred dental porcelain comprises glass having a thermal expansion coefficient of 6.0×10−6 (1/°C.) or less as a principal structural component.

Abstract: This invention relates to lead-free silicate glasses that find use in producing fine crystal glassware and in laminated ware applications. The glasses consist essentially, in weight percent, of: SiO2 52-66 ZnO 15-30 Al2O3 0-4 BaO 0-7 Li2O 0-4 MgO + CaO + SrO 0-4 Na2O  3-16 ZrO2 0-4 K2O  0-12 B2O3  0-4.

Abstract: A fixed tint, photochromic glasses and sunglass lenses produced therefrom. The glasses have R2O—Al2O3—B2O3—SiO2 base compositions, contain silver chloride and bromide contents as photochromic constituents and 0.27-0.38% and 0.035-0.060%, both by weight percent, as glass colorants, the NiO:Co3O4 ratio being at least 6:1.

Abstract: A glass composition comprising, in mole percent of the total composition: glass-forming compounds in a total amount of 75 to 85%, wherein said glass forming compounds comprise 40 to 65% SiO2, 10 to 20% Bi2O3 and 0.1 to 3% Al2O3, and glass modifiers in a total amount of 15 to 25%, wherein said glass modifiers comprise 1 to 23 % ZnO, 0.1 to 5% CuO, 0.1 to 5 CaO and 0.1 to 2% MgO, thick film formulations containing said composition and uses thereof.

Abstract: A fixed tint, photochromic glasses and sunglass lenses produced therefrom. The glasses have R.sub.2 O--Al.sub.2 O.sub.3 --B.sub.2 O.sub.3 --SiO.sub.2 base compositions, contain silver chloride and bromide contents as photochromic constituents and 0.22-0.38% NiO and 0.034-0.060% CoO, both by weight percent, as glass colorants, the NiO:CoO ratio being in the range of 5.5-7.2:1.

Abstract: The invention concerns photochromic glasses with improved properties having the following composition, in wt. %: SiO.sub.2 : 51-66, B.sub.2 O.sub.3 : 15-23, Al.sub.2 O.sub.3 : 3-10, ZrO.sub.2 : 2.5-11, TiO.sub.2 : 0-1, Li.sub.2 O: 3-7, Na.sub.2 O: 0-8, K.sub.2 O: 2-9, Ag: 0.080-0.30, CuO>0.0020-0.0130, Cl: 0.1-0.6, Br 0.040-0.3, MgO: 0-3, CaO: 0-3, SrO: 0-3, BaO: 0-3, Nb.sub.2 O.sub.5 : 0-1, La.sub.2 O.sub.3 : 0-8, Y.sub.2 O.sub.3 : 0-8, with 0.2<Ag/(Cl+Br).ltoreq.0.5, Br/(Cl+Br)>0.15, 0.5.ltoreq.La.sub.2 O.sub.3 +Y.sub.2 O.sub.3.ltoreq.8, TiO.sub.2 +Nb.sub.2 O.sub.5 .ltoreq.1.2, 10.ltoreq.Al.sub.2 O.sub.3 +ZrO.sub.2 .ltoreq.17, MgO+CaO+SrO+BaO.ltoreq.6. Use for the production of ophthalmic lenses.

Abstract: The present invention provides an oxide glass capable of exhibiting a long lasting afterglow and photostimulated phosphorescence, whereby energy can be accumulated by radiation excitation, for example, by .gamma.-rays, X-rays, UV-rays, etc., light emission can be continued for a long time even after stopping the excitation. Furthermore, the long lasting afterglow and photostimulated luminescence oxide glass can be used not only as a phosphorescent material for night illumination or night signal, but also as a material for confirming an infrared laser or controlling an optical axis because of exhibiting photostimulated luminescence by irradiation of infrared rays or visible rays. In addition, this glass is useful for recording or reproducing of .gamma.-rays, X-rays or UV-rays images. This glass material is represented, in term of atoms for making up the glass, by the following chemical composition (mol %):______________________________________ SiO.sub.2 1 to 55% B.sub.2 O.sub.3 1 to 50% (SiO.sub.2 + B.sub.2 O.

Abstract: The present invention provides high temperature sealing glass compositions for use in producing mechanically and chemically durable electrically insulating hermetic glass seals between materials such as zirconia, alumina, fosterite, steatite, carbon steels, stainless steels, and superalloys. High temperature sealing glass compositions according to the present invention include a glass component and optional vehicles. The glass component includes one or more glass frits containing in weight percent from about 17% to about 56% BaO+SrO, from about 18% to about 60% SiO.sub.2, from about 6% to about 36% B.sub.2 O.sub.3, from about 2% to about 32% Al.sub.2 O.sub.3, from about 0% to about 25% CaO plus MgO, from about 0% to about 20% Y.sub.2 O.sub.3, from about 0% to about 7% ZrO.sub.2, from about 0% to about 3% alkali oxides, from about 0% to about 5% Co.sub.3 O.sub.4, from about 0% to about 5% NiO, and from about 0% to about 3% MoO.sub.3.

Abstract: A dental porcelain composition, comprising a glassy matrix and leucite crystallites embedded therein, and having maturing temperatures in the range from about 600.degree. C. to about 885.degree. C. and CTEs in the range from about 11 to about 19, more preferably in the range from about 11.5 to about 18, and most preferably in the range from about 12 to about 17.5.times.10.sup.-6 /.degree.C. (measured from 25.degree. C. to 500.degree. C.). The tetragonal leucite is preferably both fine-grained (i.e, having average diameters of less than about 7 microns) and uniformly-sized. Preferably, the average diameters are less than about 1 to about 3 microns.

Abstract: Alkali silicate glasses are described which, in view of their good chemical stability and their optical properties and processing properties, are particularly suitable as a coating or veneering material for ceramic dental frameworks and hence for the production of all-ceramic dental restorations such as crowns or bridges.

Abstract: An alkali metal-free aluminoborosilicate glass is described which has the following composition (in % by weight based on oxide):SiO.sub.2 57-60; B.sub.2 O.sub.3 6.5-9.5; Al.sub.2 O.sub.3 14-17.5; MgO 5-8; CaO 1-4; SrO 5-8; BaO 0-3.5; with MgO+CaO+SrO+BaO 15-17; ZrO.sub.2 0.4-1.5; TiO.sub.2 0.4-1.5; CeO.sub.2 0.1-0.5; SnO.sub.2 0.2-1.The glass is particularly suitable for use as a substrate glass in display technology.

Abstract: The invention relates to a glass ceramic in which mica and ZrO.sub.2 are present in crystallized form, containing:K.sub.2 O: 0-9% by weightNa.sub.2 O: 0-9% by weight with the condition that Na.sub.2 O and K.sub.2 O together make up at least about 4% by weight,SiO.sub.2 : 35-60% by weightMgO: 10-25% by weightAl.sub.2 O.sub.3 : 7-30% by weightZrO2: 4-12% by weightF.sup.- : 2-10% by weight which is essentially free of lithium, calcium, strontium and barium, to a process for its production and to its use as a tooth replacement.

Abstract: The invention is directed to an aluminosilicate glass containing alkaline earth metals for lamp bulbs which have molybdenum components and bulb temperatures of greater than 650.degree. C. The glass has a composition in percent by weight on oxide basis as follows: SiO.sub.2 >58-62; Al.sub.2 O.sub.3 15-17.5; B.sub.2 O.sub.3 0.2-0.7; MgO 0-<1; CaO 5.5-14; SrO 0-8; BaO 6-10; ZrO 0.05-1.0; CeO.sub.2 0-0.3; TiO.sub.2 0-0.5; Br.sup.- 0-0.6 where .SIGMA. RO 21-24; (MgO+CaO+SrO)/BaO 1.45-1.75; and an alkali metal content of <0.03% by weight and a water content of <0.02% by weight.

Abstract: The invention relates to a glass composition intended for the manufacture of thermally stable substrates or panes, which comprises the following constituents in the following proportions by weight:______________________________________ SiO.sub.2 55-70% Al.sub.2 O.sub.3 0-5% or 5-10% ZrO.sub.2 5-10% or 0-5% B.sub.2 O.sub.3 0-3% Na.sub.2 O 2-6% K.sub.2 O 5-11% MgO 0-6% CaO 2-11% SrO 4-12% BaO 0-2% ______________________________________with the following relationships:Na.sub.2 O+K.sub.2 O.gtoreq.8%MgO+CaO+SrO+BaO>10%the said composition having a strain point which is in excess of 600.degree. C.

Abstract: The lead- and cadmium-free glass composition for glazing, enameling and decorating glass or glass-ceramic articles contains high quartz and/or keatite solid solution crystals as principal crystalline phases after crystallization and a low thermal expansion coefficient of less than 2.times.10.sup.-6 /K at temperatures between 20 and 700.degree. C. This glass composition contains Li.sub.2 O, 0 to 5% by weight; Na.sub.2 O, 0 to 5% by weight; K.sub.2 O, less than 2% by weight; MgO, 0 to 3% by weight; CaO, 0 to 4% by weight; SrO, 0 to 4% by weight; BaO, 0 to 4% by weight; ZnO, 0 to 4% by weight; B.sub.2 O.sub.3, 15 to 27% by weight; Al.sub.2 O.sub.3, 10 to 20% by weight; SiO.sub.2, 43 to 58% by weight; TiO.sub.2, 0 to 3% by weight and ZrO.sub.2, 0 to 4% by weight, Sb.sub.2 O.sub.3, 0 to 2% by weight; F, 0 to 3% by weight in exchange for oxygen and up to 30% by weight of at least one inorganic pigment resistant to a burning-in temperature on the glass or the glass-ceramics. The sum total amount of Li.sub.2 O, Na.

Abstract: Porcelain compositions of the present invention comprise one or more glass or glass-ceramic powder components. Additionally, one or more opacifying agents, pigments, fluorescing agents and the like may be included in the composition. Based on volume percent, 10% of the particulate in the porcelain has a particle size of less than between about 1.1 microns and about 1.5 microns, 50% of the particulate in the porcelain has a particle size of less than between about 3 and about 6 microns, 90% of the particulate in the porcelain has a particle size of less than between about 8 and about 13.5 microns, and the maximum particle size of the particulate is greater than about 20 microns and less than about 60 microns. The mean particle size is preferably in the range of about 3.0 microns to about 6.5 microns.

Abstract: The present invention provides a porcelain enamel coating composition for use in forming a coating composition upon a metal substrate having an infrared reflectivity of at least 50% at 2.5 .mu.-microns measured with a Perkin Elmer Lambda 19 UV/VIS/NIR spectrometer with a labsphere RSA-PE 19 reflectance spectroscopy accessory. The coating composition comprises a glass component and a separate and distinct addition of cerium oxide. Preferably, the coating composition comprises from about 0.20% to about 3.0% by weight of the cerium oxide.

Abstract: Opal glass compositions for producing opal glass articles such as perfume bottles are disclosed. The compositions are borosilicate compositions and further include 0.5-3.0 wt % of CaO and 1.0-6.0 wt % of P.sub.2 O.sub.5, and the sum of alkaline oxides totals 9-18 wt %.

Abstract: Described is an inorganic fiber comprising silica dioxide, calcium oxide, and alkali oxide having a free energy of hydration greater than (more positive than) -5.00 kcal/mol, an enthalpy of formation less than (more than negative than) -210.0 kcal/mol, a dissolution rate in simulated extra cellular fluid greater than 750 (calculated as nanograms of fiber/per square centimeter of fiber surface area/per hour) having an average fiber diameter not greater than 4.5 micrometers. Also described is a method of manufacturing the fibers.

Abstract: A composition which represents a new class of unleaded transparent vitreous ceramic which is described as an `Advanced or Combined Intermediate-Oxide Alkali Borosilicate. The composition comprises in combination a specially developed alkali borosilicate and a major addition selected from combinations of the group of traditionally accepted opacifiers, consisting of Zirconium, Tin, and Titanium, the said elements being present in said combination in amounts 0.5 to 43.9 wt % in terms of the Oxide form. The major addition will consist of at least two of said elements. The composition may include minor additions (.ltoreq.10 wt %) of any other element or elements which do not cause loss of transparency.

Abstract: The invention relates to a glass composition for electric lamps which glass composition comprises SiO.sub.2, Al.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, B.sub.2 O.sub.3, BaO and SrO and optionally CaO, MgO, ZnO, P.sub.2 O.sub.5, Sb.sub.2 O.sub.3, TiO.sub.2, MnO.sub.2, Fe.sub.2 O.sub.3 and/or CeO.sub.2. The composition according to the invention has a B.sub.2 O.sub.3 content of 1 to 2.8 mass %, a SrO content of 2.1 to 4.5 mass %, a BaO content of 3 to 6 mass % and of the components being present optionally, the amount of CaO is maximum 1 mass %, that of MgO is maximum 2.4 mass % and that of ZnO is maximum 3 mass %, on the condition that the total amount of SrO and B.sub.2 O.sub.3 is at least 3.6 mass %, the total amount of CaO and MgO is maximum 2.4 mass % and the total amount of MgO and ZnO is maximum 4.5 mass %.

Abstract: An optical glass has a large negative anomalous dispersion value and optical constants of refractive index (nd) within a range of 1.65-1.80 and Abbe number (.nu.d) within a range of 28-42. The optical glass includes, as its essential ingredients, in weight percent, 20-50% SiO.sub.2, 6-20% B.sub.2 O.sub.3 where SiO.sub.2 /B.sub.2 O.sub.3 .ltoreq.6, 0.5-15% ZrO.sub.2 and 31-50% Nb.sub.2 O.sub.5.

Abstract: The invention relates to glasses which absorb UV radiation and which have the following composition, in wt. %: SiO.sub.2 30-52; ZnO 0-8; B.sub.2 O.sub.3 12-22; PbO 0-2; ZrO.sub.2 5-14; Y.sub.2 O.sub.3 0-15; Al.sub.2 O.sub.3 0-12; La.sub.2 O.sub.3 5-25; Li.sub.2 O 1.5-3.5; TiO.sub.2 0-2; Na.sub.2 O 0-6; HfO.sub.2 0-2; K.sub.2 O 2-9; Nb.sub.2 O.sub.5 0-2; MgO 0-5; Ta.sub.2 O.sub.5 0-2; CaO 0-5; MoO.sub.3 0-2; SrO 0-9; WO.sub.3 0-2; BaO 0-14; SnO 0-4; Sb.sub.2 O.sub.3 0-4; SnO.sub.2 0-4; AS.sub.2 O.sub.3 0-4; CdO 0-1; CuO 0.15-1; F 0-2; Cl 0-3; Br 0-3; I 0-2 with the following conditions: Li.sub.2 O+Na.sub.2 O+K.sub.2 O (X.sub.2 O) 7-14; MgO+CaO+SrO+BaO (XO) 12-20; ZrO.sub.2 +Al.sub.2 O.sub.3 <15; F+Cl+Br+I 0.2-4.0; TiO.sub.2 +PbO+Nb.sub.2 O.sub.5 .ltoreq.2; AS.sub.2 O.sub.3 +Sb.sub.2 O.sub.3 +SnO.sub.2 +SnO 0.05-4.0 and a ratio R=(M.sub.2 O+2MO-Al.sub.2 O.sub.3 -ZrO.sub.2)/B.sub.2 O.sub.3 where M.sub.

Abstract: A mold has a moling surface of a material containing silicon carbide and/or silicon nitride as a main component and a carbon thin film formed on the molding surface to prevent fusion sticking. A glass substance which has a sag point not higher than 565.degree. C. and a predetermined composition free from arsenic oxide is introduced into the mold. The glass substance is press-formed in a heated and softened condition into a glass optical element of high precision.

Abstract: Described is an alkali-free aluminoborosilicate glass with a viscosity of 10.sup.13 dPas at a temperature of above 700.degree.0 C., a processing temperature V.sub.A of less than 1220.degree.0 C., and very good chemical stability, which can be produced in a float unit and has the following composition, in % by weight based on oxide:______________________________________ SiO.sub.2 48 -- <55 B.sub.2 O.sub.3 7 -- 15 Al.sub.2 O.sub.3 >20 -- 26 MgO 0 -- 8 CaO 4 -- 12 BaO 0 -- 2 SrO 0 -- 2 ZnO 1 -- 8 ZrO.sub.2 0 -- 2 SnO.sub.2 0.5 -- 2 ______________________________________The glass is especially suitable for use in display technology.

Abstract: A conductive glass lining composition includes 100 parts by weight of a frit and 0.05 to 1.5 parts by weight of a metal fibers of 0.1 to 30 .mu.m in diameter, 1.5 to 10 mm in length and a length-to-diameter ratio of not less than 50.

Abstract: An alkali-free glass consisting essentially of from 60 to 74 mol % of SiO.sub.2, from 10 to 16 mol % of Al.sub.2 O.sub.3, from 10 to 12 mol % of B.sub.2 O.sub.3, the molar ratio of Al.sub.2 O.sub.3 /B.sub.2 O.sub.3 being from 1.0 to 1.5, from 0 to 5 mol % of MgO, from 0 to 5 mol % of CaO, from 0 to 12 mol % of SrO, from 0 to 12 mol % of BaO, and from 6 to 12 mol % of SrO+BaO, which contains substantially no alkali metal oxide and has a strain point exceeding 650.degree. C. and an average thermal expansion coefficient of at most 40.times.10.sup.-7 /.degree.C. within a range of from 50.degree. to 300.degree. C., and of which the weight loss per unit area after immersion at 25.degree. C. for 20 minutes in a liquid prepared by mixing a 40 wt % ammonium fluoride aqueous solution and a 50 wt % hydrofluoric acid aqueous solution in a volume ratio of 9:1, is less than 0.60 mg/cm.sup.2, the weight loss per unit area after immersion at 95.degree. C. for 20 hours in 0.1N HCl, is less than 0.20 mg/cm.sup.

Abstract: The subject-matter of the invention is a glass composition, which is suitable for use in electric lamps, comprising SiO.sub.2, Al.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, SrO, B.sub.2 O.sub.3, and optionally CaO, MgO, TiO.sub.2, P.sub.2 O.sub.5, Sb.sub.2 O.sub.3, Fe.sub.2 O.sub.3, MnO.sub.2, ZnO and/or CeO.sub.2. It is characterized in that its SiO.sub.2 content is 65-73 mass %, Al.sub.2 O.sub.3 content is 0.5 to 2.5 mass %, Na.sub.2 O content is 5 to 9 mass %, K.sub.2 O content is 8 to 12 mass %, Li.sub.2 O content is 0.4 to 1.5 mass %, SrO content is 0.5 to 5 mass %, B.sub.2 O.sub.3 content is 2.1 to 5 mass %. Furthermore in addition to the components listed, it optionally also comprises maximum 2.5 mass % CaO, maximum 3.8 mass % MgO, maximum 1 mass % TiO.sub.2, maximum 0.8 mass % P.sub.2 O.sub.5, maximum 0.5 mass % Sb.sub.2 O.sub.3, maximum 0.25 mass % Fe.sub.2 O.sub.3, maximum 0.25 mass % MnO.sub.2, maximum 5 mass % ZnO, and/or maximum 0.8 mass % CeO.sub.

Abstract: The invention relates to a glass composition for electric lamps comprising SiO.sub.2, Al.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, B.sub.2 O.sub.3, BaO, CaO and MgO, in addition optionally SrO, Sb.sub.2 O.sub.3, MnO.sub.2, Fe.sub.2 O.sub.3, and/or CeO.sub.2. The glass composition according to the invention is characterized in that its B.sub.2 O.sub.3 content is 1 to 5 mass %, K.sub.2 O content is 7.2 to 11 mass %, BaO content is 5.5 to 9 mass % and MgO content is 2.1 to 4 mass %, furthermore in addition to the components listed, it optionally also comprises maximum 3.5 mass % ZnO, maximum 1.2 mass % TiO.sub.2 and maximum 0.8 mass % P.sub.2 O.sub.5 with the condition that the total amount of CaO, MgO and ZnO in the composition is at least 5.8 mass %. Stems and bulbs made of the above glass composition and used in electric lamps are also subject matters of the invention.

Abstract: The invention is directed to a method of producing a chemically pretensioned glass body. In the method, a glass body is provided having a composition in percent by weight on oxide basis: SiO.sub.2 70-85; B.sub.2 O.sub.3 8-15; Na.sub.2 O 1-5; K.sub.2 O 1-<5; Al.sub.2 O.sub.3 1-5; MgO 0-3; SrO+BaO 0-2; CaO 0-3; ZnO 0-3; with CaO+ZnO 2-6; and, ZrO.sub.2 0-3.5. The glass body is placed in an ion exchange salt bath containing at least 90% by weight of potassium salts. The salt bath is maintained at a temperature below the transformation point Tg of the glass defined by the glass composition for a duration of at least 2.0 hr causing potassium ions from the salt bath to migrate into the surface region of the glass body to thereby produce the chemically pretensioned glass body.

Abstract: A hermetically sealed implantable medical device is provided with a multi-pin arrangement including selected glass to metal or ceramic to metal seals for a feedthrough of the compression seal or matched seal type.

Abstract: A heat-resistant glass which has heat resistance sufficient for being free from viscous flowing, e.g., at a temperature of 600.degree. C. or higher, and devitrification resistance adequate for producing a panel of glass, which has, as thermal properties, an expansion coefficient equivalent or close to that of a sealing glass frit, with retaining electrical insulation properties excellent over conventional glass, and which can be used for the production of plate-shaped articles of glass such as a glass substrate, the heat-resistant glass containing, as glass components,______________________________________ 30-45% SiO.sub.2 1-10% B.sub.2 Ohd 3 1-7% Al.sub.2 O.sub.3 1-17% SrO 22-less than 35% BaO 0-5% MgO and 0-14% CaO ______________________________________the above % standing for % by weight, provided that the total amount of MgO+CaO is over 4% to 16% by weight.

Abstract: Glasses for use as substrates for flat panel displays, having a composition consisting essentially of, as calculated in weight percent on an oxide basis, of 42-62 SiO.sub.2, 15-28 Al.sub.2 O.sub.3, 0-4 B.sub.2 O.sub.3, 3-10 Na.sub.2 O, 2-12 K.sub.2 O, 0-6 MgO, 9.5-24 CaO, 0-8 SrO, 0-16 BaO, 0-4 ZrO.sub.2 and 4-16 Li.sub.2 O+Na.sub.2 O+K.sub.2 O.

Abstract: Glasses for use as substrates for flat panel displays, having a composition consisting essentially of, as calculated in weight percent on an oxide basis, 38-56 SiO.sub.2, 10-28 Al.sub.2 O.sub.3, 0-4 Li.sub.2 O, 0-6 Na.sub.2 O, 0-15 K.sub.2 O, 4-18 CaO, 0-5 MgO, more than 8 and less than or equal to about 24 SrO, 0-2 ZrO.sub.2, said glass further consisting essentially of Na.sub.2 O+K.sub.2 O in total between about 6 and 18 weight percent.

Abstract: In order to provide an alkali-free glass substrate which contains substantially no alkali metal oxide, which has chemical resistance, a high strain point, excellent meltability, and devitrification resistance, the alkali-free glass substrate contains substantially no alkali metal oxide and essentially consists, by weight, of 58.0-68.0% SiO.sub.2, 10.0-25.0% Al.sub.2 O.sub.3, 3.0-15.0% B.sub.2 O.sub.3, 0-2.9% MgO, 0-8.0% CaO, 0.1-5.0% BaO, 0.1-10.0% SrO, 0-5.0% ZnO, 0-5.0% ZrO.sub.2, and 0-5.0% TiO.sub.2.

Abstract: A glass flux composition consisting essentially in mol percent of 3.0-13.0 lithium oxide, 0.5-3.5 potassium oxide, 2.5-7.0 sodium oxide, 0.5-2.5 zinc oxide, 2.0-8.0 aluminium oxide, 15-30 boron oxide, 44-68 silica, 1.0-7.0 zirconium oxide, 0-4.0 calcium oxide, 0-3.0 lanthanum oxide, 0-1.0 other rare earth metal oxide, 0-1.0 yttrium oxide, 0-4.0 magnesium oxide, 0-4.0 strontium oxide, 0-4.0 titanium oxide, 0-10 phosphorus pentoxide, 0-1.5 lead oxide and 0-13.0 fluoride is useful for preparing an enamel or cover flux composition, especially for application to ceramic ware.

Abstract: A shaped, high-strength dental ceramic prosthesis is made by pressing a molding composition including from about 1 to 50 percent by weight glass particles and from about 99 to about 50 percent by weight inorganic oxide particles at a pressure of from about 10 to about 40 MPa and a temperature of from about 1000.degree. to about 1200.degree. C. Dental prostheses prepared in accordance with the invention include crowns, bridges, inlays and onlays.