Abstract: A wavelength-selective transmissive glass has a light transmittance Tmore than 315 nm and 400 nm or less at a wavelength of more than 315 nm and 400 nm or less represented by the formula shown below of 1% or more in terms of a plate thickness of 6 mm and a light transmittance T315 nm or less at a wavelength of 315 nm or less represented by the formula shown below of 60% or less in terms of a plate thickness of 6 mm. Ak is a weighting factor at a wavelength k (nm) for calculating T (light transmittance) defined in ISO-9050:2003, and Tk is a transmittance at the wavelength k (nm) in terms of a plate thickness of 6 mm: Tmore than 315 nm and 400 nm or less=(?k=more than 315400 Ak×Tk)/(?k=more than 315400 Ak) T315 nm or less=(?k=300315 Ak×Tk)/(?k=300315 Ak).

Abstract: To provide a highly transmissive glass and a light guide that allow high internal transmittance of plate glass to be maintained and the internal transmittance spectrum of the plate to be flattened without lowering the redox of iron to a value equal to or more than a certain value. This glass article comprises a glass which includes 1 to 80 mass ppm of total iron oxide (t-Fe2O3) in terms of Fe2O3, has a redox of iron of 0 to 50% and includes 0.01 to 4.0 mass ppm of NiO. The glass article and the light guide comprising the glass article are characterized in that an A value of the internal transmittance spectrum flatness is 0.83 or more.

Abstract: To provide a glass plate excellent in the internal transmittance of light rays in the visible region. A glass plate consisting of multicomponent oxide glass, which has an effective optical path length of from 25 to 200 cm, a thickness of from 0.5 to 10 mm, and an average internal transmittance in the visible region of at least 80% and a chromaticity Y of tristimulus values in the XYZ colorimetric system as defined in JIS Z8701 (Appendix) of at least 90%, under the effective optical path length.

Abstract: In a soda lime glass, a content of total iron calculated as Fe2O3, expressed in mass % on an oxide basis, is 0.25 to 1%, a mass proportion of divalent iron calculated as Fe2O3 in the total iron calculated as Fe2O3 is 30 to 50%, a content of total sulfur calculated as SO3, expressed in mass % on an oxide basis, is 0.003 to 0.1%, and a content of Se is 3 mass ppm or more. In the soda lime glass, visible light transmittance Tv—D65 is 30 to 55% calculated as 6 mm thickness of a glass sheet, solar direct transmittance Te is 20 to 40% calculate as 6 mm thickness of a glass sheet, and excitation purity Pe is 8.0% or less calculated as 6 mm thickness of a glass sheet.

Abstract: The present invention pertains to a glass for a data storage medium substrate which contains a specific amount of each of SiO2, Al2O3, MgO, CaO, SrO, BaO, Li2O, Na2O, and K2O, in molar percentage based on the oxides, and does not substantially contain B2O3 or ZrO2, wherein the sum of the Li2O, Na2O, and K2O contents (R2O), the molar ratio of the SiO2 content to the Al2O3 content (SiO2/Al2O3), and the molar ratio of the sum of the SiO2 and Al2O3 contents (SiO2+Al2O3) to R2O [(SiO2+Al2O3)/R2O] fall within their specific ranges, formula (1): 90<[SiO2]+2×[Al2O3]+0.8×[RO]?0.5×[R2O] [in formula (1), RO represents the sum of the MgO, CaO, SrO, and BaO contents] is satisfied, and the glass transition point Tg, the alkali resistance, and the acid resistance fall within their specific ranges.

Abstract: The present invention provides a high-transparency glass having a high fining action at a low temperature and capable of achieving redox lowering more than before. The present invention relates to a glass containing 1 to 500 ppm of a total iron oxide (t-Fe2O3) in terms of Fe2O3, having a redox ([divalent iron (Fe2+) in terms of Fe2O3]/[total (Fe2++Fe3+) of divalent iron (Fe2+) and trivalent iron (Fe3+) in terms of Fe2O3]) of 0% or more and 25% or less, containing, as expressed by mass percentage based on oxides, 50 to 81% of SiO2, 1 to 20% of Al2O3, 0 to 5% of B2O3, 5 to 20% of Li2O+Na2O+K2O, and 5 to 27% of MgO+CaO+SrO+BaO, and having a bubble disappearance-starting temperature (TD) of 1485° C. or lower.

Abstract: The present invention provides a high-transparency glass having a high fining action at a low temperature and capable of achieving redox lowering more than before. The present invention relates to a glass containing 1 to 500 ppm of a total iron oxide (t-Fe2O3) in terms of Fe2O3, having a redox ([divalent iron (Fe2+) in terms of Fe2O3]/[total (Fe2++Fe3+) of divalent iron (Fe2+) and trivalent iron (Fe3+) in terms of Fe2O3]) of 0% or more and 25% or less, containing, as expressed by mass percentage based on oxides, 50 to 81% of SiO2, 1 to 20% of Al2O3, 0 to 5% of B2O3, 5 to 20% of Li2O+Na2O+K2O, and 5 to 27% of MgO+CaO+SrO+BaO, and having a bubble disappearance-starting temperature (TD) of 1485° C. or lower.

Abstract: A glass plate, with a thickness ? of 1.0 mm or more, having first and second main surfaces and end surfaces, includes 1 to 80 weight ppm of iron in terms of Fe2O3 with 0.1 to 10.0 weight ppm of Fe2+; and 0.1 to 10.0 weight ppm of Ni, Mn, Cr, Co and V in total. In a sample with a size of 50 mm×50 mm×8 obtained from the glass plate, and an arithmetic average roughness of the main surfaces and first and second cut surfaces being 0.1 ?m or less, a first average absorbance coefficient for a wavelength of 400 to 700 nm measured on the first main surface in a normal direction is 0.009 or less, and a ratio of a second average absorbance coefficient measured on the first cut surface, to the first absorbance coefficient is 1.3 or less.

Abstract: To provide a highly transmissive glass and a light guide that allow high internal transmittance of plate glass to be maintained and the internal transmittance spectrum of the plate to be flattened without lowering the redox of iron to a value equal to or more than a certain value. This glass article comprises a glass which includes 1 to 80 mass ppm of total iron oxide (t-Fe2O3) in terms of Fe2O3, has a redox of iron of 0 to 50% and includes 0.01 to 4.0 mass ppm of NiO. The glass article and the light guide comprising the glass article are characterized in that an A value of the internal transmittance spectrum flatness is 0.83 or more.

Abstract: The present invention relates to a glass article having high transmittance, while suppressing the discoloration and the solarization of the glass. The glass article is provided by controlling the contents of cerium oxide and iron oxide in the glass composition within the optimum range, further controlling the contents of manganese oxide and iron oxide in the glass composition within the optimum range, and controlling the basicity of the alkaline earth metal oxides in the glass composition depending on the iron amount contained in the glass.

Abstract: The present invention aims to provide a heat-ray- and ultraviolet-absorbing glass plate having low solar transmittance and ultraviolet transmittance, having a high visible light transmittance, and containing a small amount of bubbles. The present invention relates to a heat-ray- and ultraviolet-absorbing glass plate that is a soda lime glass having a specific composition, having a mass proportion of divalent iron to the total iron being 50% or more, and having, as a value calculated as 4 mm thickness of the glass plate, a visible light transmittance Tv of 66% or more, a solar transmittance Te of 65% or less, a ratio Tv/Te of Tv and Te of 1.3 or more, and an ultraviolet transmittance Tuv of 50% or less.

Abstract: To provide a highly transmissive glass and a light guide that allow high internal transmittance of plate glass to be maintained and the internal transmittance spectrum of the plate to be flattened without lowering the redox of iron to a value equal to or more than a certain value. This glass article comprises a glass which includes 1 to 80 mass ppm of total iron oxide (t-Fe2O3) in terms of Fe2O3, has a redox of iron of 0 to 50% and includes 0.01 to 4.0 mass ppm of NiO. The glass article and the light guide comprising the glass article are characterized in that an A value of the internal transmittance spectrum flatness is 0.83 or more.

Abstract: A white glass contains, in terms of mole percentage on the basis of the following oxides, from 50 to 80% of SiO2, from 0 to 10% of Al2O3, from 11 to 30% of MgO, from 0 to 15% of Na2O and from 0.5 to 15% of P2O5.

Abstract: The present invention provides a high-transparency glass having a high fining action at a low temperature and capable of achieving redox lowering more than before. The present invention relates to a glass containing 1 to 500 ppm of a total iron oxide (t-Fe2O3) in terms of Fe2O3, having a redox ([divalent iron (Fe2+) in terms of Fe2O3]/[total (Fe2++Fe3+) of divalent iron (Fe2+) and trivalent iron (Fe3+) in terms of Fe2O3]) of 0% or more and 25% or less, containing, as expressed by mass percentage based on oxides, 50 to 81% of SiO2, 1 to 20% of Al2O3, 0 to 5% of B2O3, 5 to 20% of Li2O+Na2O+K2O, and 5 to 27% of MgO+CaO+SrO+BaO, and having a bubble disappearance-starting temperature (TD) of 1485° C. or lower.

Abstract: A glass plate for a light guide plate includes a first glass layer; a second glass layer facing the first glass layer; and a third glass layer that is an intermediate glass layer formed between the first glass layer and the second glass layer, wherein the glass plate is provided with a three layer structure in a plate thickness direction, and wherein the glass plate satisfies t1C/(t1B1+t1B2+t1C)<0.03 . . . (1); n1C>n1B1 . . . (2); and n1C>n1B2 . . . (3), where t1B1 is a thickness of the first glass layer, t1B2 is a thickness of the second glass layer, t1C is a thickness of the third glass layer, n1B1 is a refractive index of the first glass layer, n1B2 is a refractive index of the second glass layer, and n1C is a refractive index of the third glass layer.

Abstract: A glass plate for a light guide plate includes a light emitting surface; and a light scattering surface that is opposite to the light emitting surface, wherein a refractive index distribution is provided between the light emitting surface and the light scattering surface in a plate thickness direction, and wherein a refractive index calculated from a measured value of reflectance of the light scattering surface is greater than a refractive index of an inner part of the glass plate measured by a V block method after each of the light emitting surface and the light scattering surface is polished and removed by 100 microns.

Abstract: A process for producing a chemically strengthened glass is provided. The method for producing a chemically strengthened glass includes subjecting a phase-separated glass to an ion exchange treatment. A chemically strengthened glass which is obtained by the process and a phase-separated glass which has been subjected to the ion exchange treatment are also provided.

Abstract: To provide glass having a favorable color tone, and its production process. Glass comprising, as represented by mass percentage based on oxides, at least 60% and at most 75% of SiO2, at least 8% and at most 20% of Na2O, at least 4.5% of MgO, at least 1% and at most 10% of CaO, and at least 0.01% and at most 0.5% of Er2O3.

Abstract: To provide a glass plate excellent in the internal transmittance of light rays in the visible region. A glass plate consisting of multicomponent oxide glass, which has an effective optical path length of from 25 to 200 cm, a thickness of from 0.5 to 10 mm, and an average internal transmittance in the visible region of at least 80% and a chromaticity Y of tristimulus values in the XYZ colorimetric system as defined in JIS Z8701 (Appendix) of at least 90%, under the effective optical path length.

Abstract: A white glass contains, in terms of mole percentage on the basis of the following oxides, from 50 to 80% of SiO2, from 0 to 10% of Al2O3, from 11 to 30% of MgO, from 0 to 15% of Na2O and from 0.5 to 15% of P2O5.