Abstract: To provide a glass for an information recording media substrate, which is excellent in weather resistance. A glass for an information recording media substrate, which comprises, as represented by mol % based on oxide, from 61 to 66% of SiO2, from 11.5 to 17% of Al2O3, from 8 to 16% of Li2O, from 2 to 8% of Na2O, from 2.5 to 8% of K2O, from 0 to 6% of MgO, from 0 to 4% of TiO2 and from 0 to 3% of ZrO2, provided that Al2O3+MgO+TiO2 is at least 12%, and Li2O+Na2O+K2O is from 16 to 23%, wherein in a case of where B2O3 is contained, its content is less than 1%. The above glass for an information recording media substrate, wherein when the glass is left under steam atmosphere at 120° C. at 0.2 MPa for 20 hours, and the amount of Li, the amount of Na and the amount of K, which precipitate on a surface of the glass are represented as CLi, CNa and CK respectively, CNa is at most 0.7 nmol/cm2, and CLi+CNa+CK is at most 3.5 nmol/cm2.

Abstract: To provide an alkali-free glass excellent in the properties for glass substrates to be used for display, excellent in the resistance to reduction, and suitable for forming by a float process. An alkali-free glass consisting essentially of, as represented by mol %: SiO2 at least 60% and less than 66%, Al2O3 0 to 12%, B2O3 5 to 10%, MgO 0 to 18%, CaO 0 to 18%, SrO 0 to 18%, BaO 0 to 6%,? CaO + SrO 10 to 25%,? MgO + CaO + SrO + BaO 15.5 to 30%?? and containing substantially no alkali metal oxide.

Abstract: To provide a substrate glass for data storage medium which is excellent in weather resistance even when no additional treatment such as chemical reinforcement treatment is applied and less susceptible to a whitening phenomenon and which has a glass transition temperature of at least 680° C. and is excellent in acid resistance. A substrate glass for data storage medium, which comprises, as represented by mass %, from 47 to 60% of SiO2, from 8 to 20% of Al2O3, from 0 to 8% of MgO, from 0 to 6% of CaO, from 1 to 18% of SrO, from 0 to 13% of BaO, from 1 to 6% of TiO2, from 1 to 5% of ZrO2, from 2 to 8% of Na2O and from 1 to 15% of K2O and which has a glass transition temperature of at least 680° C.

Abstract: To provide glass for a data storage medium substrate, whereby high heat resistance can be obtained. Glass for a data storage medium substrate, which comprises, as represented by mol percentage based on the following oxides, from 55 to 70% of SiO2, from 2.5 to 9% of Al2O3, from 0 to 10% of MgO, from 0 to 7% of CaO, from 0.5 to 10% of SrO, from 0 to 12.5% of BaO, from 0 to 2.5% of TiO2, from 0.5 to 3.7% of ZrO2, from 0 to 2.5% of Li2O, from 0 to 8% of Na2O, from 2 to 8% of K2O and from 0.5 to 5% of La2O3, provided that the total content of Al2O3and ZrO2(Al2O3+ZrO2) is at most 12%, and the total content of Li2O, Na2O and K2O (R2O) is at most 12%.

Abstract: A glass composition for substrates excellent in productivity is provided by lowering the high temperature viscosity while securing characteristics and quality required for FPD substrates, particularly for PDP substrates. A glass composition for substrates, which is characterized by comprising, as represented by mass% based on oxides, from 55 to 75% of SiO2, from 5 to 15% of Al2O3, from 4 to 18% of MgO, from 3 to 12% of CaO, from 4 to 18% of SrO, from 0 to 20% of BaO, from 6 to 20% of Na2O+K2O, from 0.5 to 6% of ZrO2 and from 18 to 25% of MgO+CaO+SrO+BaO, as a glass matrix composition, and containing from 0.001 to 0.6% of SO3, and which is further characterized in that when the viscosity is represented by q, the temperature satisfying log?=2 is at most 1,545° C. and the devitrification temperature is at most the temperature satisfying log?=4, the thermal expansion coefficient is from 75×10?7 to 90×10?7/° C., the specific gravity is at most 2.8, and the glass transition point is at least 600° C.

Abstract: To provide an alkali free glass which is suitable as a glass substrate for LCD and has few defects of bubbles and an undissolved starting material, and a process for producing an alkali free glass which can readily lower the defects in bubbles and an undissolved starting material. An alkali free glass with a matrix composition comprising SiO2, Al2O3, B2O3, MgO, CaO, SrO and BaO and containing substantially no alkali metal oxide, of which the temperature at which the viscosity becomes 102 dPa·s, is at most 1,600° C. and which contains sulfur in an amount of from 0.001 to 0.1% as calculated as SO3, as represented by the mass percentage, per 100% of the total amount of the above matrix composition, and a process for producing a glass which comprises preparing a starting material and melting it so that a sulfate be incorporated to the starting material in an amount of from 0.01 to 5% as calculated as SO3, as represented by the mass percentage, per 100% of the total amount of the above matrix composition.

Abstract: To provide a glass plate for display devices wherein without carrying out a post treatment, the depth of a compression stress layer is increased, while the surface compression stress is prevented from being excess only by chemical tempering. A glass plate for display devices, which is obtained by chemically tempering a glass plate comprising, as represented by mol % based on the following oxides, from 50 to 74% of SiO2, from 1 to 10% of Al2O3, from 6 to 14% of Na2O, from 3 to 15% of K2O, from 2 to 15% of MgO, from 0 to 10% of CaO and from 0 to 5% of ZrO2, wherein the total content of SiO2 and Al2O3 is at most 75%, the total content of Na2O and K2O, i.e. Na2O+K2O, is from 12 to 25%, and the total content of MgO and CaO, i.e. MgO+CaO, is from 7 to 15%.

Abstract: The present invention provides a glass substrate for flat panel display in which yellowing occurring in a case of forming silver electrodes on glass substrate surface is inhibited. A glass substrate for flat panel display, which is formed by a float method, which has a composition consisting essentially of, in terms of oxide amount in mass %: SiO2 50 to 72%, Al2O3 0.15 to 15%, MgO + CaO + SrO + BaO 4 to 30%, Na2O more than 0% and at most 10%, K2O 1 to 21%, Li2O 0 to 1%, Na2O + K2O + Li2O 6 to 25%, ZrO2 0 to 10%, and Fe2O3 0.0725 to 0.15%; and wherein the average Fe2+ content in a surface layer of the glass substrate within a depth of 10 ?m from the top surface is at most 0.0725% in terms of Fe2O3 amount.

Abstract: To provide a substrate glass for data storage medium which is excellent in weather resistance even when no additional treatment such as chemical reinforcement treatment is applied and less susceptible to a whitening phenomenon and which has a glass transition temperature of at least 680° C. and is excellent in acid resistance. A substrate glass for data storage medium, which comprises, as represented by mass %, from 47 to 60% of SiO2, from 8 to 20% of Al2O3, from 0 to 8% of MgO, from 0 to 6% of CaO, from 1 to 18% of SrO, from 0 to 13% of BaO, from 1 to 6% of TiO2, from 1 to 5% of ZrO2, from 2 to 8% of Na2O and from 1 to 15% of K2O and which has a glass transition temperature of at least 680° C.

Abstract: To provide glass for a data storage medium substrate, whereby high heat resistance can be obtained. Glass for a data storage medium substrate, which comprises, as represented by mol percentage based on the following oxides, from 55 to 70% of SiO2, from 2.5 to 9% of Al2O3, from 0 to 10% of MgO, from 0 to 7% of CaO, from 0.5 to 10% of SrO, from 0 to 12.5% of BaO, from 0 to 2.5% of TiO2, from 0.5 to 3.7% of ZrO2, from 0 to 2.5% of Li2O, from 0 to 8% of Na2O, from 2 to 8% of K2O and from 0.5 to 5% of La2O3, provided that the total content of Al2O3 and ZrO2 (Al2O3+ZrO2) is at most 12%, and the total content of Li2O, Na2O and K2O (R2O) is at most 12%.

Abstract: To provide a float glass for a display substrate, of which the high temperature viscosity is low, without impairing properties for a substrate glass for a display. A float glass for a display substrate, characterized in that its composition consists essentially of, as represented by mass % based on oxide, from 52 to 62% of SiO2, from 5 to 15% of Al2O3, from more than 0% to 9% of MgO, from 3 to 12% of CaO, from 9 to 18% of SrO, from 0 to 13% of BaO, from 25 to 30% of MgO+CaO+SrO+BaO, from 6 to 14% of Na2O+K2O+Li2O, from 0 to 6% of ZrO2 and from 0 to 1% of SO3, the temperature of glass melt corresponding to the viscosity of 102 dPa·s is at most 1,520° C., the temperature of glass melt corresponding to the viscosity of 104 dPa·s is at most 1,120° C., the glass transition temperature is at least 610° C., and the specific gravity is at most 2.9.

Abstract: To provide a glass for an information recording media substrate, which is excellent in weather resistance. A glass for an information recording media substrate, which comprises, as represented by mol % based on oxide, from 61 to 66% of SiO2, from 11.5 to 17% of Al2O3, from 8 to 16% of Li2O, from 2 to 8% of Na2O, from 2.5 to 8% of K2O, from 0 to 6% of MgO, from 0 to 4% of TiO2 and from 0 to 3% of ZrO2, provided that Al2O3+MgO+TiO2 is at least 12%, and Li2O+Na2O+K2O is from 16 to 23%, wherein in a case of where B2O3 is contained, its content is less than 1%. The above glass for an information recording media substrate, wherein when the glass is left under steam atmosphere at 120° C. at 0.2 MPa for 20 hours, and the amount of Li, the amount of Na and the amount of K, which precipitate on a surface of the glass are represented as CLi, CNa and CK respectively, CNa is at most 0.7 nmol/cm2, and CLi+CNa+CK is at most 3.5 nmol/cm2.

Abstract: A substrate with film and a glass for forming such a film are provided, wherein the film has high gas barrier property, high transmittance in visible light region, and high productivity since the film provides effective gas barrier property even if the film is a single layer. A substrate with film having an inorganic amorphous film having a softening temperature of from 100 to 800° C. formed on at least one surface of a substrate; or a substrate with film having an inorganic amorphous film having a glass transition temperature of from 50 to 500° C. formed on at least one surface of a substrate. Further, a glass for forming film composed of a borate glass containing B2O3 as the main component, a phosphate glass containing P2O5, a tellurite type composition containing TeO2 as the main component, a bismuth oxide type composition containing Bi2O3 as the main component or a chalcogenide type composition containing at least one type of element selected from the group consisting of S, Se and Te.

Abstract: To provide a process for producing and alkali free glass for effectively suppressing bubbles, and an alkali free glass produced by the process, which is suitable as a glass substrate for flat panel displays and has few bubbles. A process for producing an alkali free glass containing substantially no alkali metal oxide, which comprises melting a glass starting material having a matrix composition of the following composition, and subjecting the molten glass to a treatment process of removing bubbles under reduced pressure, stirring or transferring under a condition where the molten glass is in contact with a platinum member, wherein the starting material is prepared so as to contain SnO2 in an amount of from 0.01 to 2.0% per 100% of the total amount of the above matrix composition; the starting material is melted under heating at from 1,500 to 1,650° C.

Abstract: Provided is a crystallized glass spacer for a field emission display resistant to charging with application of an electric field and resistant to chipping or cracking thanks to high fracture toughness. An SiO2—TiO2-based glass is subjected to a reduction and crystallization heat treatment at 600-900° C. in a hydrogen atmosphere or in a mixed atmosphere of hydrogen and nitrogen, to obtain a crystallized glass spacer for FED consisting essentially of, in molar percentage, SiO2: 20-50%, TiO2: 25-45%, MgO+CaO+SrO+BaO+ZnO: 20-50%, B2O3+Al2O3: 0-10% and ZrO2: 0-10%, and containing as a principal crystal at least one crystal selected from BaXTi8O16-based crystals (X=0.8-1.5), Ba2TiSi2O8-based crystals and TiO2-based crystals.

Abstract: To provide an alkali free glass which is suitable as a glass substrate for LCD and has few defects of bubbles and an undissolved starting material, and a process for producing an alkali free glass which can readily lower the defects in bubbles and an undissolved starting material. An alkali free glass with a matrix composition comprising SiO2, Al2O3, B2O3, MgO, CaO, SrO and BaO and containing substantially no alkali metal oxide, of which the temperature at which the viscosity becomes 102 dPa·s, is at most 1,600° C. and which contains sulfur in an amount of from 0.001 to 0.1% as calculated as SO3, as represented by the mass percentage, per 100% of the total amount of the above matrix composition, and a process for producing a glass which comprises preparing a starting material and melting it so that a sulfate be incorporated to the starting material in an amount of from 0.01 to 5% as calculated as SO3, as represented by the mass percentage, per 100% of the total amount of the above matrix composition.

Abstract: Provided is a crystallized glass spacer for a field emission display resistant to charging with application of an electric field and resistant to chipping or cracking thanks to high fracture toughness. An SiO2—TiO2-based glass is subjected to a reduction and crystallization heat treatment at 600-900° C. in a hydrogen atmosphere or in a mixed atmosphere of hydrogen and nitrogen, to obtain a crystallized glass spacer for FED consisting essentially of, in molar percentage, SiO2: 20-50%, TiO2: 25-45%, MgO+CaO+SrO+BaO+ZnO: 20-50%, B2O3+Al2O3: 0-10% and ZrO2: 0-10%, and containing as a principal crystal at least one crystal selected from BaXTi8O16-based crystals (X=0.8-1.5), Ba2TiSi2O8-based crystals and TiO2-based crystals.

Abstract: To provide an alkali-free glass excellent in the properties for glass substrates to be used for display, excellent in the resistance to reduction, and suitable for forming by a float process. An alkali-free glass consisting essentially of, as represented by mol %: SiO2 at least 60% and less than 66%, Al2O3 0 to 12%, B2O3 5 to 10%, MgO 0 to 18%, CaO 0 to 18%, SrO 0 to 18%, BaO 0 to 6%,? CaO + SrO 10 to 25%,? MgO + CaO + SrO + BaO 15.5 to 30%?? and containing substantially no alkali metal oxide.

Abstract: To provide a glass for a display substrate which has solved yellowing problems. A glass plate for a display substrate, which contains at least one member selected from the group consisting of Ti, Mn, Zn, Y, Nb, La, Ce and W in an amount of from 0.1 to 10 mass % as calculated as oxides.

Abstract: A crystallized glass for an optical filter substrate, which has an average linear expansion coefficient ?L of from 95×10?7/° C. to 130×10?7/° C. at from ?30° C. to 70° C. and which has a crystal or the like of Na4-xKxAl4Si4O16 (1<x?4) precipitated therein. Further, a crystallized glass for an optical filter substrate, which comprises from 35 to 60% of SiO2, from 10 to 30% of Al2O3, from 1 to 15% of TiO2+ZrO2, from 4 to 20% of Na2O, from 4 to 20% of K2O, from 0.1 to 10% of CaO+SrO+Bao, from 0 to 10% of MgO, etc., and which has ?L of from 95×10?7/° C. to 130×10?7/° C. and which has a crystal or solid solution precipitated therein.