Abstract: A method for manufacturing a float glass includes a step of melting a glass raw material, a step of forming the glass melted in the melting step into a glass ribbon while floating the glass on a molten metal, and a step of annealing the glass ribbon. In the forming step, a gas or a liquid containing a molecule having a fluorine atom present therein is blown to the glass ribbon having a viscosity of from 1.0×104 to 2.5×1010 Pa·s.

Abstract: The present invention relates to a glass sheet having a fluorine concentration at one surface larger than a fluorine concentration at the other surface, the surfaces being opposite to each other in a thickness direction, in which the following Formula (1) is satisfied and the amount of fluorine contained in the glass is more than 0.23 mol %·?m and 21 mol %·?m or less on a depth-direction profile by secondary ion mass spectrometry (SIMS) in which a horizontal axis expresses depth and a vertical axis expresses fluorine concentration (mol %). The fluorine concentration is an average fluorine concentration (mol %) by SIMS in the depth of from 1 to 24 ?m. 0.1??F/?H2O??(1) (?F and ?H2O are described in the specification).

Abstract: A glass sheet has one surface and the other surface facing the one surface in a thickness direction, wherein a fluorine concentration (average fluorine concentration by SIMS at a depth of 1 to 24 ?m) in the one surface is higher than that in the other surface. The following expression is satisfied: 0.07??F/?H2O. ?F (mol %) is a value obtained by subtracting an average fluorine concentration in the surface having the lower fluorine concentration from that in the surface having the higher fluorine concentration, and ?H2O (mol %) is an absolute value of a value obtained by subtracting an average H2O concentration in the surface having the higher fluorine concentration from that in the surface having the lower fluorine concentration.

Abstract: A float glass for chemical strengthening, having a bottom surface to contact a molten metal during molding and a top surface facing the bottom surface. An absolute value of a difference between a normalized hydrogen concentration at a depth of 5 to 10 ?m that is a value obtained by dividing a hydrogen concentration at a depth of 5 to 10 ?m by a hydrogen concentration at a depth of 50 to 55 ?m in the top surface and the normalized hydrogen concentration at a depth of 5 to 10 ?m in the bottom surface is 0.35 or less.

Abstract: A method for manufacturing a float glass includes a step of melting a glass raw material, a step of forming the glass melted in the melting step into a glass ribbon while floating the glass on a molten metal, and a step of annealing the glass ribbon. In the forming step, a gas or a liquid containing a molecule having a fluorine atom present therein is blown to the glass ribbon having a viscosity of from 1.0×104 to 2.5×1010 Pa·s.

Abstract: The present invention relates to a glass sheet having an amount of fluorine contained in the glass of more than 0.23 mol %·?m and 21 mol %·?m or less on a depth-direction profile by secondary ion mass spectrometry (SIMS) in which a horizontal axis expresses depth and a vertical axis expresses fluorine concentration (mol %). According to the glass sheet of the present invention, warpage after chemical strengthening can be reduced and polishing treatment or the like before the chemical strengthening can be simplified or omitted.

Abstract: The present invention relates to a method for manufacturing a float glass containing a step of melting a glass raw material, a step of forming the glass melted by the preceding step into a glass ribbon while floating the glass on a molten metal, and a step of annealing the glass ribbon. In the forming step, a fluid containing a molecule having a fluorine atom is sprayed onto the glass ribbon to control a fluorine amount in the depth of up to 30 ?m in the thickness direction from the upper surface of the glass ribbon to more than 0.23 mol %·?m.

Abstract: The present invention relates to a glass sheet having a fluorine concentration at one surface larger than a fluorine concentration at the other surface, the surfaces being opposite to each other in a thickness direction, in which the following Formula (1) is satisfied and the amount of fluorine contained in the glass is more than 0.23 mol %·?m and 21 mol %·?m or less on a depth-direction profile by secondary ion mass spectrometry (SIMS) in which a horizontal axis expresses depth and a vertical axis expresses fluorine concentration (mol %). The fluorine concentration is an average fluorine concentration (mol %) by SIMS in the depth of from 1 to 24 ?m. 0.1??F/?H2O ??(1) (?F and ?H2O are described in the specification).

Abstract: The present invention relates to a glass sheet having a fluorine concentration at one surface larger than that at the other surface, in which the following Formula (1) is satisfied and the amount of fluorine contained in the glass is more than 0.23 mol %·?m and 21 mol %·?m or less on a depth-direction profile by SIMS. The fluorine concentration is an average fluorine concentration (mol %) by SIMS in the depth of from 1 to 24 ?m. 1?x??(1) (x is a maximum depth (?m) in which a slope at an arbitrary depth xi (?m) in the fluorine concentration profile by SIMS satisfies the following Formula (2)). [F(xi+0.1)?F(xi)]/0.1=?0.015??(2) (F(xi) represents a fluorine concentration (mol %) by SIMS at the depth xi (?m)).

Abstract: An area S (m2) of a facing surface of each of injectors which faces a glass ribbon is set so as to satisfy: S?(0.0116×P×Cg×T)/{?×F×?(Tgla4?Tinj4)}, wherein P is an output (ton/day) of the glass ribbon; Cg is a specific heat (J/(kg·° C.)) of the glass; T is an acceptable temperature drop (° C.); ? is radiation factor; F is a surface-to-surface view factor; ? is Boltzmann's constant; Tgla is a temperature (K) of the glass ribbon represented by K=(Tin+Tout)/2 where Tin and Tout are measured values of the glass ribbon at the inlet and outlet of the injector, respectively; and Tinj is a temperature (K) of the facing surface of the injector.

Abstract: A glass sheet has one surface and the other surface facing the one surface in a thickness direction, wherein a fluorine concentration (average fluorine concentration by SIMS at a depth of 1 to 24 ?m) in the one surface is higher than that in the other surface. The following expression is satisfied: 0.07??F/?H2O. ?F (mol %) is a value obtained by subtracting an average fluorine concentration in the surface having the lower fluorine concentration from that in the surface having the higher fluorine concentration, and ?H2O (mol %) is an absolute value of a value obtained by subtracting an average H2O concentration in the surface having the higher fluorine concentration from that in the surface having the lower fluorine concentration.

Abstract: An area S (m2) of a facing surface of each of injectors which faces a glass ribbon is set so as to satisfy: S?(0.0116×P×Cg×T)/{?×F×?(Tgla4?Tinj4)}, wherein P is an output (ton/day) of the glass ribbon; Cg is a specific heat (J/(kg·° C.)) of the glass; T is an acceptable temperature drop (° C.); ? is radiation factor; F is a surface-to-surface view factor; ? is Boltzmann's constant; Tgla is a temperature (K) of the glass ribbon represented by K=(Tin+Tout)/2 where Tin and Tout are measured values of the glass ribbon at the inlet and outlet of the injector, respectively; and Tinj is a temperature (K) of the facing surface of the injector.

Abstract: A method for manufacturing a laminated film-coated glass substrate in which a laminated film is formed on a glass ribbon by a CVD method by means of a plurality of injectors disposed in the annealing furnace, wherein: the laminated film is formed at Tg+50° C. or lower; and in each of the injectors, if a quantity of heat exchanged between the injector and the glass ribbon is expressed by Q1 (kW), a quantity of heat exchanged between a heater paired with the injector and the glass ribbon is expressed by Q2 (kW), and an output of the glass is expressed by P (tons/day), then the relational expression |Q1|?P×0.116?|Q2|?|Q1| is satisfied.

Abstract: A method for manufacturing a laminated film-coated glass substrate in which a laminated film is formed on a glass ribbon by a CVD method by means of a plurality of injectors disposed in an annealing furnace and the glass ribbon is cut, wherein the laminated film is formed at Tg+50° C. or lower and at least two layers of the laminated film are formed in a temperature range of Tg+50° C. to Tg. In addition, a temperature drop K1 per unit length of the glass ribbon in a temperature range where all layers of the laminated film are formed is 0° C./m<K1<10° C./m.

Abstract: A float glass for chemical strengthening, having a bottom surface to contact a molten metal during molding and a top surface facing the bottom surface. An absolute value of a difference between a normalized hydrogen concentration at a depth of 5 to 10 ?m that is a value obtained by dividing a hydrogen concentration at a depth of 5 to 10 ?m by a hydrogen concentration at a depth of 50 to 55 ?m in the top surface and the normalized hydrogen concentration at a depth of 5 to 10 ?m in the bottom surface is 0.35 or less.