Abstract: A substrate for p-Si TFT flat panel displays made of a glass having a high low-temperature-viscosity characteristic temperature and manufactured while avoiding erosion/wear of a melting tank during melting through direct electrical heating. The glass substrate comprises 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-20 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-0.8 mass % of R2O, wherein R2O is total amount of Li2O, Na2O, and K2O, and 0-0.3 mass % of Sb2O3, and substantially does not comprise As2O3, wherein the mass ratio CaO/RO is equal to or greater than 0.65, the mass ratio (SiO2+Al2O3)/B2O3 is in a range of 7-30, and the mass ratio (SiO2+Al2O3)/RO is equal to or greater than 5. A related method involves melting glass raw materials blended to provide the glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: A flat panel display glass substrate according to the present invention includes a glass comprising, as expressed in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, 3-25% RO (the total amount of MgO, CaO, SrO, and BaO), and substantially no As2O3, and Sb2O3. The devitrification temperature of the glass is 1250° C. or less. The glass substrate has a heat shrinkage rate of 75 ppm or less. The heat shrinkage rate is calculated from the amount of shrinkage of the glass substrate measured after a heat treatment which is performed at a temperature rising and falling rate of 10° C./min and at 550° C. for 2 hours by the heat shrinkage rate (ppm)={the amount of shrinkage of the glass substrate after the heat treatment/the length of the glass substrate before the heat treatment}×106.

Abstract: The disclosed cover glass is produced by etching a glass substrate that has been formed by a down-drawing process, and chemically strengthening the glass substrate to provide the glass substrate with a compressive-stress layer on the principal surfaces thereof. The glass substrate contains, as components thereof, 50% to 70% by mass of SiO2, 5% to 20% by mass of Al2O3, 6% to 30% by mass of Na2O, and 0% to less than 8% by mass of Li2O. The glass substrate may also contain 0% to 2.6% by mass of CaO, if necessary. The glass substrate has an etching characteristic in which the etching rate is at least 3.7 ?m/minute in an etching environment having a temperature of 22° C. and containing hydrogen fluoride with a concentration of 10% by mass.

Abstract: A glass substrate for p-Si TFT flat panel displays that is composed of a glass comprising 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-25 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-1 mass % of Fe2O3, and 0-0.3 mass % of Sb2O3, and substantially not comprising As2O3, the glass having a mass ratio (SiO2+Al2O3)/B2O3 in a range of 7-30 and a mass ratio (SiO2+Al2O3)/RO equal to or greater than 6. A method for manufacturing a glass substrate involves: a melting step of obtaining a molten glass by melting, by employing at least direct electrical heating, glass raw materials blended so as to provide the aforementioned glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: A glass substrate for p-Si TFT flat panel displays that is composed of a glass comprising 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-25 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-1 mass % of Fe2O3, and 0-0.3 mass % of Sb2O3, and substantially not comprising As2O3, the glass having a mass ratio (SiO2+Al2O3)/B2O3 in a range of 7-30 and a mass ratio (SiO2+Al2O3)/RO equal to or greater than 6. A method for manufacturing a glass substrate involves: a melting step of obtaining a molten glass by melting, by employing at least direct electrical heating, glass raw materials blended so as to provide the aforementioned glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: A substrate for p-Si TFT flat panel displays made of a glass having a high low-temperature-viscosity characteristic temperature and manufactured while avoiding erosion/wear of a melting tank during melting through direct electrical heating. The glass substrate comprises 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-20 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-0.8 mass % of R2O, wherein R2O is total amount of Li2O, Na2O, and K2O, and 0-0.3 mass % of Sb2O3, and substantially does not comprise As2O3, wherein the mass ratio CaO/RO is equal to or greater than 0.65, the mass ratio (SiO2+Al2O3)/B2O3 is in a range of 7-30, and the mass ratio (SiO2+Al2O3)/RO is equal to or greater than 5. A related method involves melting glass raw materials blended to provide the glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: A flat panel display glass substrate includes a glass comprising, in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, and 3-25% RO (the total amount of MgO, CaO, SrO, and BaO). The contents in mol % of SiO2, Al2O3, and B2O3 satisfy a relationship (SiO2+Al2O3)/(B2O3)=7.5-17. The strain point of the glass is 665° C. or more. The devitrification temperature of the glass is 1250° C. or less. The substrate has a heat shrinkage rate of 75 ppm or less. The rate of heat shrinkage is calculated from the amount of shrinkage of the substrate measured after a heat treatment which is performed at a rising and falling temperature rate of 10° C./min and at 550° C. for 2 hours by the rate of heat shrinkage (ppm)={the amount of shrinkage of the substrate after the heat treatment/the length of the substrate before the heat treatment}×106.

Abstract: The disclosed cover glass is produced by etching a glass substrate that has been formed by a down-drawing process, and chemically strengthening the glass substrate to provide the glass substrate with a compressive-stress layer on the principal surfaces thereof. The glass substrate contains, as components thereof, 50% to 70% by mass of SiO2, 5% to 20% by mass of Al2O3, 6% to 30% by mass of Na2O, and 0% to less than 8% by mass of Li2O. The glass substrate may also contain 0% to 2.6% by mass of CaO, if necessary. The glass substrate has an etching characteristic in which the etching rate is at least 3.7 ?m/minute in an etching environment having a temperature of 22° C. and containing hydrogen fluoride with a concentration of 10% by mass.

Abstract: A substrate for p-Si TFT flat panel displays made of a glass having a high low-temperature-viscosity characteristic temperature and manufactured while avoiding erosion/wear of a melting tank during melting through direct electrical heating. The glass substrate comprises 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-20 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-0.8 mass % of R2O, wherein R2O is total amount of Li2O, Na2O, and K2O, and 0-0.3 mass % of Sb2O3, and substantially does not comprise As2O3, wherein the mass ratio CaO/RO is equal to or greater than 0.65, the mass ratio (SiO2+Al2O3)/B2O3 is in a range of 7-30, and the mass ratio (SiO2+Al2O3)/RO is equal to or greater than 5. A related method involves melting glass raw materials blended to provide the glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: Provided are: a glass substrate for p-Si TFT flat panel displays that is composed of a glass having high characteristic temperatures in the low-temperature viscosity range, typified by the strain point and glass transition point, having a small heat shrinkage rate, and being capable of avoiding the occurrence of the problem regarding the erosion/wear of a melting tank at the time of melting through direct electrical heating; and a method for manufacturing same. The present glass substrate is composed of a glass comprising 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-25 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-1 mass % of Fe2O3, and 0-0.3 mass % of Sb2O3, and substantially not comprising As2O3, the glass having a mass ratio (SiO2+Al2O3)/B2O3 in a range of 7-30 and a mass ratio (SiO2+Al2O3)/RO equal to or greater than 6.

Abstract: Provided are: a glass substrate for p-Si TFT flat panel displays that is composed of a glass having high characteristic temperatures in the low-temperature viscosity range, typified by the strain point and glass transition point, having a small heat shrinkage rate, and being capable of avoiding the occurrence of the problem regarding the erosion/wear of a melting tank at the time of melting through direct electrical heating; and a method for manufacturing same. The present glass substrate is composed of a glass comprising 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-25 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-1 mass % of Fe2O3, and 0-0.3 mass % of Sb2O3, and substantially not comprising As2O3, the glass having a mass ratio (SiO2+Al2O3)/B2O3 in a range of 7-30 and a mass ratio (SiO2+Al2O3)/RO equal to or greater than 6.

Abstract: A flat panel display glass substrate includes a glass comprising, in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, and 3-25% RO (the total amount of MgO, CaO, SrO, and BaO). The contents in mol % of SiO2, Al2O3, and B2O3 satisfy a relationship (SiO2+Al2O3)/(B2O3)=7.5-17. The strain point of the glass is 665° C. or more. The devitrification temperature of the glass is 1250° C. or less. The substrate has a heat shrinkage rate of 75 ppm or less. The rate of heat shrinkage is calculated from the amount of shrinkage of the substrate measured after a heat treatment which is performed at a rising and falling temperature rate of 10° C./min and at 550° C. for 2 hours by the rate of heat shrinkage (ppm)={the amount of shrinkage of the substrate after the heat treatment/the length of the substrate before the heat treatment}×106.

Abstract: A flat panel display glass substrate according to the present invention includes a glass comprising, as expressed in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, 3-25% RO (the total amount of MgO, CaO, SrO, and BaO), and substantially no As2O3 and Sb2O3. The devitrification temperature of the glass is 1250° C. or less. The glass substrate has a heat shrinkage rate of 75 ppm or less. The heat shrinkage rate is calculated from the amount of shrinkage of the glass substrate measured after a heat treatment which is performed at a temperature rising and falling rate of 10° C./min and at 550° C. for 2 hours by the heat shrinkage rate (ppm)={the amount of shrinkage of the glass substrate after the heat treatment/the length of the glass substrate before the heat treatment}×106.

Abstract: A cover glass having a compressive-stress layer on the principal surfaces thereof, and having a glass composition containing 50% to 70% by mole of SiO2, 3% to 20% by mole of Al2O3, 5% to 25% by mole of Na2O, more than 0% by mole and less than or equal to 2.5% by mole of Li2O, 0% to 5.5% by mole of K2O, and 0% to less than 3% by mole of B2O3. Also disclosed is a method for producing a cover glass which includes: (i) preparing molten glass by melting a glass raw material; (ii) forming the prepared molten glass into a plate-like shape by a down-draw process and thereby obtaining a glass substrate; and (iii) forming a compressive-stress layer on the surface of the glass substrate.

Abstract: A flat panel display glass substrate according to the present invention includes a glass comprising, as expressed in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, 3-25% RO (the total amount of MgO, CaO, SrO, and BaO), and substantially no As2O3, and Sb2O3. The devitrification temperature of the glass is 1250° C. or less. The glass substrate has a heat shrinkage rate of 75 ppm or less. The heat shrinkage rate is calculated from the amount of shrinkage of the glass substrate measured after a heat treatment which is performed at a temperature rising and falling rate of 10° C./min and at 550° C. for 2 hours by the heat shrinkage rate (ppm)={the amount of shrinkage of the glass substrate after the heat treatment/the length of the glass substrate before the heat treatment}×106.

Abstract: A glass substrate for p-Si TFT flat panel displays that is composed of a glass comprising 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-25 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-1 mass % of Fe2O3, and 0-0.3 mass % of Sb2O3, and substantially not comprising As2O3, the glass having a mass ratio (SiO2+Al2O3)/B2O3 in a range of 7-30 and a mass ratio (SiO2+Al2O3)/RO equal to or greater than 6. A method for manufacturing a glass substrate involves: a melting step of obtaining a molten glass by melting, by employing at least direct electrical heating, glass raw materials blended so as to provide the aforementioned glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: A flat panel display glass substrate includes a glass comprising, in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, and 3-25% RO (the total amount of MgO, CaO, SrO, and BaO). The contents in mol % of SiO2, Al2O3, and B2O3 satisfy a relationship (SiO2+Al2O3)/(B2O3)=7.5-17. The strain point of the glass is 665° C. or more. The devitrification temperature of the glass is 1250° C. or less. The substrate has a heat shrinkage rate of 75 ppm or less. The rate of heat shrinkage is calculated from the amount of shrinkage of the substrate measured after a heat treatment which is performed at a rising and falling temperature rate of 10° C./min and at 550° C. for 2 hours by the rate of heat shrinkage (ppm)={the amount of shrinkage of the substrate after the heat treatment/the length of the substrate before the heat treatment}×106.

Abstract: A substrate for p-Si TFT flat panel displays made of a glass having a high low-temperature-viscosity characteristic temperature and manufactured while avoiding erosion/wear of a melting tank during melting through direct electrical heating. The glass substrate comprises 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-20 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-0.8 mass % of R2O, wherein R2O is total amount of Li2O, Na2O, and K2O, and 0-0.3 mass % of Sb2O3, and substantially does not comprise As2O3, wherein the mass ratio CaO/RO is equal to or greater than 0.65, the mass ratio (SiO2+Al2O3)/B2O3 is in a range of 7-30, and the mass ratio (SiO2+Al2O3)/RO is equal to or greater than 5. A related method involves melting glass raw materials blended to provide the glass composition; a forming step of forming the molten glass into a flat-plate glass; and an annealing step of annealing the flat-plate glass.

Abstract: Provided are: a glass substrate for p-Si TFT flat panel displays that is composed of a glass having high characteristic temperatures in the low-temperature viscosity range, typified by the strain point and glass transition point, having a small heat shrinkage rate, and being capable of avoiding the occurrence of the problem regarding the erosion/wear of a melting tank at the time of melting through direct electrical heating; and a method for manufacturing same. The present glass substrate is composed of a glass comprising 52-78 mass % of SiO2, 3-25 mass % of Al2O3, 3-15 mass % of B2O3, 3-25 mass % of RO, wherein RO is total amount of MgO, CaO, SrO, and BaO, 0.01-1 mass % of Fe2O3, and 0-0.3 mass % of Sb2O3, and substantially not comprising As2O3, the glass having a mass ratio (SiO2+Al2O3)/B2O3 in a range of 7-30 and a mass ratio (SiO2+Al2O3)/RO equal to or greater than 6.

Abstract: A flat panel display glass substrate according to the present invention includes a glass comprising, as expressed in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, 3-25% RO (the total amount of MgO, CaO, SrO, and BaO), and substantially no As2O3 and Sb2O3. The devitrification temperature of the glass is 1250° C. or less. The glass substrate has a heat shrinkage rate of 75 ppm or less. The heat shrinkage rate is calculated from the amount of shrinkage of the glass substrate measured after a heat treatment which is performed at a temperature rising and falling rate of 10° C./min and at 550° C. for 2 hours by the heat shrinkage rate (ppm)={the amount of shrinkage of the glass substrate after the heat treatment/the length of the glass substrate before the heat treatment}×106.