Abstract: A front glass plate for a stacked structure includes greater than or equal to 5 mol % of Al2O3, in terms of an oxide, as a component, 50% crack initiation load of the front glass plate being greater than or equal to 0.5 kg.

Abstract: To provide a method for producing chemically tempered glass, whereby frequency of replacement of the molten salt can be reduced. A method for producing chemically tempered glass, which comprises repeating ion exchange treatment of immersing glass in a molten salt, wherein the glass comprises, as represented by mole percentage, from 61 to 77% of SiO2, from 1 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 6% of K2O; SiO2+Al2O3 is from 65 to 85%; MgO+CaO is from 3 to 15%; and R calculated by the following formula by using contents of the respective components, is at least 0.66: R=0.029×SiO2+0.021×Al2O3+0.016×MgO?0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O?2.

Abstract: There are provided a method for measuring strength of a chemically strengthened glass, that reflects the state of actual drop fracture more appropriately, and can reproduce slow cracking in the chemically strengthened glass, a method for reproducing cracking of a chemically strengthened glass, and a method for producing a chemically strengthened glass. Load is applied to an indenter having a tip formed into a sharp shape having a minimum angle ?min of cross-section of less than 120°, the indenter is pushed into a chemically strengthened glass under a static load condition such that the tip is vertical to a surface of the chemically strengthened glass, and the load when the chemically strengthened glass cracks is measured.

Abstract: The present invention provides a cover glass for a display, having high durability to slow cracking and strong abraded strength even though a compressive stress is large and a depth of a compressive stress layer is deep. The present invention relates to a cover glass for a display, in which a depth of a compressive stress layer (DOL) is 30 ?m or more, a surface compressive stress is 300 MPa or more, a position (HW) at which a compressive stress is half of a value of the surface compressive stress is a position of 8 ?m or more from a glass surface, and the depth of the compressive stress layer (DOL) and the position (HW) at which the compressive stress is half of the value of the surface compressive stress satisfy the following formula: 0.05?HW/DOL?0.23??(1).

Abstract: A Glass for chemical tempering, which includes, as represented by mole percentage based on the following oxides, from 60 to 75% of SiO2, from 5 to 15% of Al2O3, more than 7 and at most 12% of MgO, from 0 to 3% of CaO, from 0 to 3% of ZrO2, from 10 to 20% of Li2O, from 0 to 8% of Na2O and from 0 to 5% of K2O, and has a total content R2O of Li2O, Na2O and K2O of at most 25%, and a ratio Li2O/R2O of the Li2O content to R2O of from 0.5 to 1.0.

Abstract: To provide chemically tempered glass which is less likely to break even if scratched. Chemically tempered glass, which comprises, as represented by mole percentage based on the following oxides, from 56 to 72% of SiO2, from 8 to 20% of Al2O3, from 9 to 25% of Na2O, from 0 to 2% of K2O, and from 0 to 15% of MgO, and which has a surface compressive stress of at least 900 MPa and an internal tensile stress of at most 30 MPa. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 56 to 69% of SiO2, from 8 to 16% of Al2O3, from 9 to 22% of Na2O, from 0 to 1% of K2O, from 5.5 to 14% of MgO, from 0 to 2% of ZrO2, and from 0 to 6% of B2O3.

Abstract: The present invention provides a method for producing a chemically strengthened glass for a display device, which is capable of suppressing generation of concave defects. The present invention relates to a method for producing a chemically strengthened glass substrate for a display device, in which a calcium concentration in a cleaning liquid used in a final cleaning step before a chemical strengthening step is 5 ppm or less.

Abstract: To provide a plasma display device whereby it is possible to improve the image quality and at the same time to reduce warpage of a thin cover glass plate having a large area. A plasma display device 10 is provided which comprises a plasma display panel 20 provided with glass substrates 21, 22, and a cover glass plate 30 bonded to the display side of the plasma display panel 20, wherein the cover glass plate 30 has a diagonal length of at least 81 cm and a thickness of at most 1.5 mm, and the average thermal expansion coefficient of the cover glass plate 30 is from 80 to 120% of the average thermal expansion coefficient of the glass substrates 21, 22 within a range of from 50 to 350° C.

Abstract: To provide glass to be used for chemically tempered glass which is hardly broken even when flawed. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 65 to 85% of SiO2, from 3 to 15% of Al2O3, from 5 to 15% of Na2O, from 0 and less than 2% of K2O, from 0 to 15% of MgO and from 0 to 1% of ZrO2, and has a total content Si02+Al2O3 of SiO2 and Al2O3 of at most 88%.

Abstract: To provide a process for producing a chemically tempered glass whereby it is possible to increase the surface compressive stress. A process for producing a chemically tempered glass, which comprises holding a glass at a temperature of at least the strain point minus 40° C. and at most the strain point plus 70° C. for at least 30 minutes for heat treatment, and thereafter, immersing it in a molten salt for ion exchange without allowing the temperature to exceed the strain point plus 70° C.

Abstract: In this method for producing an ornament (1), wherein an ornamental sheet (3) is bonded/affixed by means of a vacuum-press-bonding method to the convex front surface (21) of a substrate (2) provided with a convex front surface (21) and a concave back surface (22), a work-support base (6) is placed on a work placement surface (121a) formed on the upper surface of the suction chamber (120) of a vacuum-press-bonding device (100), and the substrate (2) is positioned by fitting an engagement protrusion (28) formed on the back surface of the substrate (2) covered by the ornamental sheet (3) to an engagement hole (68) at the work-support surface (61) formed on the upper surface of the work-support base (6). When bonding/affixing the ornamental sheet (3) to the substrate (2) by means of the vacuum-press-bonding device (100), position deviation of the substrate (2) is prevented by the engagement of the engagement hole (68) and the engagement protrusion (28).

Abstract: To provide glass to be used for chemically tempered glass which is hardly broken even when flawed. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 65 to 85% of SiO2, from 3 to 15% of Al2O3, from 5 to 15% of Na2O, from 0 and less than 2% of K2O, from 0 to 15% of MgO and from 0 to 1% of ZrO2, and has a total content SiO2+Al2O3 of SiO2 and Al2O3 of at most 88%.

Abstract: There are provided a method for measuring strength of a chemically strengthened glass, that reflects the state of actual drop fracture more appropriately, and can reproduce slow cracking in the chemically strengthened glass, a method for reproducing cracking of a chemically strengthened glass, and a method for producing a chemically strengthened glass. Load is applied to an indenter having a tip formed into a sharp shape having a minimum angle ?min of cross-section of less than 120° , the indenter is pushed into a chemically strengthened glass under a static load condition such that the tip is vertical to a surface of the chemically strengthened glass, and the load when the chemically strengthened glass cracks is measured.

Abstract: To provide glass to be used for chemically tempered glass which is hardly broken even when flawed. Glass for chemical tempering, which comprises, as represented by mole percentage based on the following oxides, from 65 to 85% of SiO2, from 3 to 15% of Al2O3, from 5 to 15% of Na2O, from 0 and less than 2% of K2O, from 0 to 15% of MgO and from 0 to 1% of ZrO2, and has a total content SiO2+Al2O3 of SiO2 and Al2O3 of at most 88%.

Abstract: To provide a method for producing chemically tempered glass, whereby frequency of replacement of the molten salt can be reduced. A method for producing chemically tempered glass, which comprises repeating ion exchange treatment of immersing glass in a molten salt, wherein the glass comprises, as represented by mole percentage, from 61 to 77% of SiO2, from 1 to 18% of Al2O3, from 3 to 15% of MgO, from 0 to 5% of CaO, from 0 to 4% of ZrO2, from 8 to 18% of Na2O and from 0 to 6% of K2O; SiO2+Al2O3 is from 65 to 85%; MgO+CaO is from 3 to 15%; and R calculated by the following formula by using contents of the respective components, is at least 0.66: R=0.029×SiO2+0.021×Al2O3+0.016×MgO?0.004×CaO+0.016×ZrO2+0.029×Na2O+0×K2O?2.

Abstract: To provide a method for producing chemically tempered glass, whereby the chemical tempering can be done at a low temperature and in a short time. A method for producing chemically tempered glass, which comprises chemically tempering glass for chemical tempering, comprising, as represented by mole percentage based on the following oxides, from 60 to 75% of SiO2, from 5 to 15% of Al2O3, from 1 to 12% of MgO, from 0 to 3% of CaO, from 0 to 3% of ZrO2, from 10 to 20% of Li2O, from 0 to 8% of Na2O and from 0 to 5% of K2O, and having a total content R2O of Li2O, Na2O and K2O of at most 25%, and a ratio Li2O/R2O of the Li2O content to R2O of from 0.5 to 1.0.

Abstract: The present invention relates to a process for producing a chemically strengthened glass, which includes conducting a sampling inspection including a measurement of a refractive index distribution of a glass. According to the process of the invention, the surface compressive stress and the depth of the compressive stress layer of the chemically strengthened glass can be stably and accurately measured.

Abstract: The present invention relates to a process for producing a chemically strengthened glass substrate for a display device, the process including a pre-heating step of pre-heating a glass to a pre-heating temperature and subsequently an ion exchange step of immersing the glass in a chemical strengthening liquid, in which the pre-heating temperature in the pre-heating step and a strain point of the glass satisfy: 220° C.?(strain point?pre-heating temperature).

Abstract: A cover glass for flat panel displays, which is difficult to be spontaneously destroyed is provided. The present invention relates to a cover glass for flat panel displays, obtained by chemically strengthening a glass obtained by a fusion process, in which the glass before chemical strengthening does not contain defects having a particle size of 40 ?m or more, and the cover glass has an internal tensile stress of 30 MPa or more and a thickness of 1.5 mm or less.