Provided is a method comprises: continuously forming an elongated, glass film having marginal portions from molten glass into a given shape having two marginal portions, in width-directional opposite edge regions thereof, wherein the glass film having marginal portions has the marginal portions, and an effective portion formed in a width-directional central region of the glass film having marginal portions; annealing the glass film having marginal portions; continuously forming resin tapes on the glass film having marginal portions at positions adjacent to and away by a given distance from the respective marginal portions, to extend in a length direction of the glass film having marginal portions; and continuously removing each of the marginal portions from the glass film having marginal portions, along a position between the marginal portion and a corresponding one of the resin tapes, or at a given width-directional position within the corresponding resin tape.

A method for manufacturing a glass substrate having a strain point of 680° C. or higher, the method includes: a step of melting a glass raw material; and a step of forming a molten glass, in which the forming step includes a step of cooling the molten glass such that a cooling time in a temperature range from an annealing point of the glass substrate to 500° C. is 35 seconds or more, and in a case where a cooling profile indicating a temperature change with respect to the cooling time is linearly approximated by a least-squares method in the temperature range from the annealing point of the glass substrate to 500° C., a coefficient of determination R.sup.2 in the least-squares method is 0.7 or more.

A method of predicting the gravity-free shape of a glass sheet and a method of managing the quality of a glass sheet based on the gravity-free shape of the glass sheet. The initial shape of a glass sheet is determined. When the glass sheet is flattened, values of stress at a plurality of locations in the glass sheet are obtained. A shape that the glass sheet will have when the flattened glass sheet is deformed such that the values of stress are zero is predicted as a stress-induced shape and a gravity-free shape of the glass sheet is predicted by combining the initial shape and the stress-induced shape. Quality management is performed on glass sheets based on gravity-free shapes thereof predicted using the method of predicting the gravity-free shape of a glass sheet.

A method for making a heat-resistant roll includes pre-selecting a plurality of heat-resistant disks and pressing at least a selected portion of the pre-selected disks together such that a total axial thickness of the pressed disks relative to a total axial thickness of the selected disks prior to pressing is within a predetermined range.

Methods of producing a glass article include melting a first glass composition and feeding a second glass composition into the melter. Both glass compositions include the same combination of components but at least one component has a concentration that is different in each. At least three glass articles may be drawn from the melter, including: a first glass article formed from the first glass composition; at least one intermediate glass article composed of neither the first nor the second glass composition; and a final glass article not composed of the first glass composition. The concentration of the at least one component in the intermediate glass article may be between the concentration in the first and second glass compositions. The first glass article and final glass article may have differing values for certain properties, and the intermediate glass article may have an intermediate set of values for the same properties.

Methods of producing a glass article include melting a first glass composition and feeding a second glass composition into the melter. Both glass compositions include the same combination of components but at least one component has a concentration that is different in each. At least three glass articles may be drawn from the melter, including: a first glass article formed from the first glass composition; at least one intermediate glass article composed of neither the first nor the second glass composition; and a final glass article not composed of the first glass composition. The concentration of the at least one component in the intermediate glass article may be between the concentration in the first and second glass compositions. The first glass article and final glass article may have differing values for certain properties, and the intermediate glass article may have an intermediate set of values for the same properties.

A tempered glass sheet of the present invention is a tempered glass sheet having a compressive stress layer in a surface thereof, wherein the tempered glass sheet comprises as a glass composition, in terms of mol %, 50% to 75% of SiO.sub.2, 1% to 20% of Al.sub.2O.sub.3, 5% to 30% of B.sub.2O.sub.3, 0% to 15% of Li.sub.2O, 1% to 25% of Na.sub.2O, 0% to 10% of K.sub.2O, and 0% to 15% of P.sub.2O.sub.5, wherein the tempered glass sheet has a molar ratio [Al.sub.2O.sub.3]/[Na.sub.2O] of from 0.1 to 2.5, and wherein the tempered glass sheet satisfies the following relationship:

[SiO.sub.2]−3×[Al.sub.2O.sub.3]−[B.sub.2O.sub.3]−2×[Li.sub.2O]−1.5×[Na.sub.2O]−[K.sub.2O]+1.2×[P.sub.2O.sub.5]≥−20%.

Methods for producing a glass sheet are provided. The methods can include forming a glass ribbon from molten glass, applying a polymer precursor to at least a portion of a first or second major surface of the glass ribbon, curing the polymer precursor to form a polymer coating, and separating the glass ribbon to produce at least one glass sheet. Glass ribbons and glass sheets produced by these methods are also disclosed.

A laminated glass article includes a glass core layer and a glass cladding layer adjacent to the glass core layer. At least one of the glass core layer or the glass cladding layer is a tinted layer. The tinted layer can include a tinting agent that imparts a color to the tinted layer.

Provided is a method of manufacturing a glass sheet, which comprises a conveying step of conveying a glass sheet (G3) by holding an upper part of the glass sheet (G3) in a vertical posture. The conveying step comprises a first conveying step of conveying the glass sheet (G3) in a first direction along a direction perpendicular to a main surface of the glass sheet (G3), and a second conveying step of conveying the glass sheet (G3) in a second direction along a direction parallel to the main surface after the first conveying step. When a conveying direction of the glass sheet is changed from the first direction to the second direction, a lower part of the main surface (G3y) is supported by a roller (41) of a support portion (4) from a forward side in the conveying direction of the glass sheet (G3) conveyed in the first direction.