The present invention relates to an alkali-free glass substrate, having a strain point of 680 C. or higher, a Young's modulus of 78 GPa or greater, an UV transmittance at a wavelength of 300 nm of from 40% to 85% in terms of 0.5 mm thickness, an in-plane distribution of the UV transmittance at a wavelength of 300 nm in a G6-sized substrate of 1% or less in terms of 0.5 mm thickness, an average cooling rate around the glass transition point obtained according to a rate cooling method of 400 C./min or lower, and an in-plane distribution of the average cooling rate of 40 C./min or less.

The present invention refers to a glass composition and a method for the commercial production of a solar control thin green glass mainly for use in the automotive industry such as symmetric-hybrid windshields or asymmetric-hybrid windshields, sidelights and rear windows, which includes a basic composition of soda-lime-silica glass, and consists essentially, in weight percentage: from 1.30 to 2.50% of total iron expressed as Fe.sub.2O.sub.3; from 15 to 40% of Fe.sup.2+ (Ferrous) and from 0.15 to 0.65% of FeO, expressed as Fe.sub.2O.sub.3; from about 0.05 to about 0.30% of SO.sub.3; from about 0.02 to about 1.0% of TiO.sub.2; from about 0.0002 to about 0.03% of Cr.sub.2O.sub.3; and from about 0.0002 to about 0.015% of CuO. The solar control thin green glass having an illuminant A light transmission (T.sub.LA) greater than 70%, a direct solar transmittance (T.sub.DS) of less than 51%, a total UV light transmittance (T.sub.UV) of less than 40% and a total solar transmittance (T.sub.TS) of less than 63%; a dominant wavelength () from 490 nm to 600; and excitation purity less than 7, for thickness from about 0.7 to 3.0 mm.

An ultraviolet transmitting glass containing, in mole percentage based on oxides, 55 to 80% of SiO.sub.2, 12 to 27% of B.sub.2O.sub.3, 4 to 20% of R20 (where R represents an alkali metal selected from a group consisting of Li, Na, and K) in total, 0 to 3.5% of Al.sub.2O.sub.3, 0 to 5% of RO (where R represents an alkaline earth metal selected from a group consisting of Mg, Ca, Sr, and Ba) in total, 0 to 5% of ZnO, and 0 to 10% of ZrO.sub.2, wherein transmittance at a wavelength of 254 nm in terms of spectral transmittance at a plate thickness of 0.5 mm is 70% or more. The glass with high ultraviolet light transmittance, in particular, high deep ultraviolet light transmittance is provided.

A UV lamp including a filter material of doped quartz glass is provided that effects a transparency as high as possible for operating radiation in the ultraviolet spectral range above 210 nm together with low transparency in the wavelength range below about 190 nm. The filter material of doped quartz glass includes at least 99 wt. % of SiO.sub.2 and Al.sub.2O.sub.3, wherein the Al.sub.2O.sub.3 portion is in the range of 2 wt. % to 4 wt. The filter material has an edge wavelength at a wavelength below 190 nm and a spectral transmission of 80% mm.sup.1 or higher at a wavelength of 210 nm.

Provided is a glass substrate with which it is possible to reduce dielectric loss in high-frequency signals, and which also has excellent thermal shock resistance. This invention satisfies the relation {Young's modulus (GPa)average thermal expansion coefficient (ppm/ C.) at 50-350 C.}300 (GPa.Math.ppm/ C.), wherein the relative dielectric constant at 20 C. and 35 GHz does not exceed 10, and the dielectric dissipation factor at 20 C. and 35 GHz does not exceed 0.006.

A glass composition, wherein components thereof are represented by weight percentage, including: 50-70% of SiO.sub.2; 3-20% of B.sub.2O.sub.3; 11-25% of Al.sub.2O.sub.3; 1-15% of CaO; 0-10% of MgO. Through rational component design, the glass composition features excellent chemical stability, high UV light transmittance and transition temperature, so as to meet the requirements for carrier and packaging in semiconductor manufacturing process and to be applicable for semiconductor manufacturing field.

Provided is a glass substrate with which it is possible to reduce dielectric loss in high-frequency signals, and which also has excellent thermal shock resistance. This invention satisfies the relation {Young's modulus (GPa)average thermal expansion coefficient (ppm/ C.) at 50-350 C.}300 (GPa.Math.ppm/ C.), wherein the relative permittivity at 20 C. and 35 GHz does not exceed 10, and the dielectric loss tangent at 20 C. and 35 GHz does not exceed 0.006.

Glass materials, glass articles, and sheets of glass materials are disclosed, as well as methods of making these, in which the glass materials comprise alkaline earth metals and have a high deep UV transmission, such as greater than 50% at wavelengths of 245-270 nm, and are further compatible with or formable by large scale manufacturing techniques such as fusion drawing.

The present invention relates to an alkali-free glass substrate, having a strain point of 680 C. or higher, a Young's modulus of 78 GPa or greater, an UV transmittance at a wavelength of 300 nm of from 40% to 85% in terms of 0.5 mm thickness, an in-plane distribution of the UV transmittance at a wavelength of 300 nm in a G6-sized substrate of 1% or less in terms of 0.5 mm thickness, an average cooling rate around the glass transition point obtained according to a rate cooling method of 400 C./min or lower, and an in-plane distribution of the average cooling rate of 40 C./min or less.

The present invention relates to an alkali-free glass substrate, having a strain point of 680 C. or higher, a Young's modulus of 78 GPa or greater, an UV transmittance at a wavelength of 300 nm of from 40% to 85% in terms of 0.5 mm thickness, an in-plane distribution of the UV transmittance at a wavelength of 300 nm in a G6-sized substrate of 1% or less in terms of 0.5 mm thickness, an average cooling rate around the glass transition point obtained according to a rate cooling method of 400 C./min or lower, and an in-plane distribution of the average cooling rate of 40 C./min or less.