Abstract: A method for producing a silica container that includes forming a powder mixture by adding an Al compound or a crystal nucleating agent into a first powdered raw material (silica particles), preliminarily molding to an intended shape by feeding the powder mixture to an inner wall of an outer frame while rotating the outer frame having aspiration holes, forming a silica substrate, wherein the preliminarily molded article is degassed by aspiration from a peripheral side and at the same time heated from inside the preliminarily molded article at high temperature thereby making a peripheral part of the preliminarily molded article to a sintered body while an inner part to a fused glass body, and forming a transparent silica glass layer on an inner surface of the silica substrate, wherein a second powdered raw material having a higher silica purity than the first powdered raw material is spread from inside the silica substrate and at the same time heated from the inside at high temperature.

Abstract: A method for producing a silica container comprising: forming a preliminarily molded substrate, wherein a first powdered raw material is fed to an inner wall of an outer frame having aspiration holes while rotating the outer frame; forming a preliminarily molded intermediate layer, wherein a second powdered raw material added with an aluminum compound or a crystal nucleating agent as an additive is fed to an inner wall of the preliminarily molded substrate; and forming an inner layer, wherein the preliminarily molded substrate and the preliminarily molded intermediate layer are degassed by aspiration from a peripheral side with heating from an inside thereby forming a substrate and an intermediate layer, and while a third powdered raw material having a high silica purity is spread from inside the substrate having the formed intermediate layer with heating from the inside thereby forming an inner layer on an inner surface of the intermediate layer.

Abstract: The present invention is a method for producing a silica container having a substrate containing gaseous bubbles in its outer peripheral part and an inner layer comprised of a transparent silica glass formed on an inner surface of the substrate, wherein a powdered raw material for forming a substrate containing Li, Na, and K with the total concentration of 50 or less ppm by weight and a powdered raw material for forming an inner layer containing Ca, Sr, and Ba with the total concentration of 50 to 2000 ppm by weight are prepared; a preliminarily molded substrate is formed in a frame; a preliminarily molded inner layer is formed on an inner surface of the preliminarily molded substrate; and the preliminarily molded substrate and molded inner layer are heated from inside thereof by a discharge-heat melting method under a gas atmosphere containing a hydrogen gas or a helium gas or a gas mixture thereof with the ratio of more than 10% by volume thereby making an outer peripheral part of the preliminarily molded s

Abstract: A method is provided for producing a silica container arranged with a substrate, having a rotational symmetry, comprised of mainly a silica, and containing gaseous bubbles at least in its peripheral part, and an inner layer, formed on an inner surface of the substrate and comprised of a transparent silica glass; wherein a powdered silica, having particle diameter of 10 to 1000 ?m, containing Ca, Sr, and Ba with the total concentration of 50 to 5000 ppm by weight, and releasing hydrogen molecules with the amount of 3×1016 to 3×1019 molecules/g upon heating at 1000° C. under vacuum, is prepared at least as a powdered raw material for forming the inner layer, and then the inner layer is formed from the powdered silica as the powdered raw material for forming the inner layer.

Abstract: A method for producing a silica container having a rotational symmetry is provided. The method includes, forming a preliminarily molded article by feeding a powdered substrate's raw material to an inner wall of an outer frame having aspiration holes with rotating the frame, and forming a silica substrate. The preliminarily molded article is aspirated from an outer peripheral side with controlling a humidity inside the outer frame by ventilating gases present in the outer frame with charging from inside the preliminarily molded article a gas mixture comprised of an O2 gas and an inert gas and made below a prescribed dew-point temperature by dehumidification, and at the same time heated from inside the preliminarily molded article by a discharge-heat melting method with carbon electrodes, thereby making an outer peripheral part of the preliminarily molded article to a sintered body while an inner peripheral part to a fused glass body.

Abstract: A method for producing a silica container, the method including forming a preliminarily molded silica substrate to an intended shape by feeding a powdered substrate's raw material (silica particles) to an inner wall of a carbon-made outer frame having aspiration holes with rotating the outer frame, and forming the silica substrate wherein the preliminarily molded substrate is degassed by aspiration from its outer peripheral side with charging from an inner peripheral side of the preliminarily molded silica substrate a reducing gas containing more than 10% by volume of an H2 gas, and at the same time heated from inside the preliminarily molded silica substrate by a discharge-heat melting method with carbon electrodes, thereby making an outer peripheral part of the preliminarily molded silica substrate to a sintered body while an inner peripheral part of the preliminarily molded silica substrate to a fused glass body.

Abstract: A method for producing a silica container that includes forming a powder mixture by adding an Al compound or a crystal nucleating agent into a first powdered raw material (silica particles), preliminarily molding to an intended shape by feeding the powder mixture to an inner wall of an outer frame while rotating the outer frame having aspiration holes, forming a silica substrate, wherein the preliminarily molded article is degassed by aspiration from a peripheral side and at the same time heated from inside the preliminarily molded article at high temperature thereby making a peripheral part of the preliminarily molded article to a sintered body while an inner part to a fused glass body, and forming a transparent silica glass layer on an inner surface of the silica substrate, wherein a second powdered raw material having a higher silica purity than the first powdered raw material is spread from inside the silica substrate and at the same time heated from the inside at high temperature.

Abstract: The present invention provides a method for producing a silica container, wherein the method comprises: a step of forming a preliminarily molded substrate, wherein a first powdered raw material (silica particles) is fed to an inner wall of an outer frame having aspiration holes while rotating the outer frame, a step of forming a preliminarily molded intermediate layer, wherein a second powdered raw material (silica particles) added with an aluminum compound or a crystal nucleating agent as an additive is fed to an inner wall of the preliminarily molded substrate, and a step of forming an inner layer, wherein the preliminarily molded substrate and the preliminarily molded intermediate layer are degassed by aspiration from a peripheral side with heating from an inside thereby forming a substrate and an intermediate layer, and while a third powdered raw material having a high silica purity is spread from inside the substrate having the formed intermediate layer with heating from the inside thereby forming an inn

Abstract: The problem to be solved is to provide an automobile interior headliner member which is improved in the film forming property of a complex plastic material used as a base material of the automobile interior headliner member, and has high rigidity and excellent heat resistance, size stability and working efficiency upon attachment; and the base material. An automobile interior headliner molding or forming member which is obtained by kneading mica having a particle size of 10 to 100 &mgr;m with a polypropylene resin having a melt flow rate at 230° C. of 3 to 40 g/10 min to obtain the corresponding resin having a mica content of 15 to 40 wt. %, molding or forming the resin into a mica-containing polypropylene sheet of 100 to 300 &mgr;m thick and then stacking this sheet over each of both sides of an expanded polypropylene sheet of 2 to 6 mm thick obtained at an expansion ratio of 5 to 50 times; and an automobile interior headliner member molded or formed from the molding or forming member.

Abstract: A silica glass optical material for projection lens to be used in vacuum ultraviolet radiation lithography using radiation from 155 to 195 nm in wavelength, wherein, said silica glass optical material is of ultrahigh purity, contains from 1 to 10 wtppm of OH groups, from 100 to 10,000 wtppm of F, and from 1×1017 to 1×1019 molecules/cm3 of H2, and has a distribution in concentration of F that is axially symmetrical to the central axis.

Abstract: A silica glass optical material for transmitting light with a wavelength of from 155 to 195 nm emitted from an excimer laser or an excimer lamp, which comprises silica glass optical material of ultrahigh purity, containing from 1 to 100 wtppm of OH groups, from 5×1016 to 5×1019 molecules/cm3 of H2, and from 10 to 10,000 wtppm of F, but substantially free from halogens other than F, and having a fluctuation in refractive index, &Dgr;n, of from 3×10−6 to 3×10−7.

Abstract: The problem to be solved is to provide an automobile interior headliner member which is improved in the film forming property of a complex plastic material used as a base material of the automobile interior headliner member, and has high rigidity and excellent heat resistance, size stability and working efficiency upon attachment; and the base material.An automobile interior headliner molding or forming member which is obtained by kneading mica having a particle size of 10 to 100 µm with a polypropylene resin having a melt flow rate at 230°C of 3 to 40 g/10 min to obtain the corresponding resin having a mica content of 15 to 40 wt.%, molding or forming the resin into a mica-containing polypropylene sheet of 100 to 300 µm thick and then stacking this sheet over each of both sides of an expanded polypropylene sheet of 2 to 6 mm thick obtained at an expansion ratio of 5 to 50 times; and an automobile interior headliner member molded or formed from the molding or forming member.

Abstract: The problem to be solved is to provide an automobile interior headliner member which is improved in the film forming property of a complex plastic material used as a base material of the automobile interior headliner member, and has high rigidity and excellent heat resistance, size stability and working efficiency upon attachment; and the base material. An automobile interior headliner molding or forming member which is obtained by kneading mica having a particle size of 10 to 100 &mgr;m with a polypropylene resin having a melt flow rate at 230° C. of 3 to 40 g/10 min to obtain the corresponding resin having a mica content of 15 to 40 wt. %, molding or forming the resin into a mica-containing polypropylene sheet of 100 to 300 &mgr;m thick and then stacking this sheet over each of both sides of an expanded polypropylene sheet of 2 to 6 mm thick obtained at an expansion ratio of 5 to 50 times; and an automobile interior headliner member molded or formed from the molding or forming member.

Abstract: A method of producing an optical component for the transmission of UV light is provided. An optical fiber is prepared from synthetic quartz glass or from doped synthetic quartz glass with a transmission region for the transmission of UV light, and the transmission region is charged with hydrogen and/or with deuterium. The charging includes coating the fiber with a blocking layer inhibiting hydrogen diffusion, and charging the fiber in an atmosphere containing hydrogen and/or deuterium. This atmosphere is under a pressure in the range from 0.1 MPa to 200 MPa and at a temperature between 100° C. and 800° C. so as to produce a concentration of said hydrogen and/or deuterium of at least 5×1019 molecules/cm3 in the transmission region. The coating and charging steps may be performed repeatedly, and the blocking layer is built up to comprise a plurality of thinner layers including a top layer, after application of which charging is discontinued.

Abstract: An object of the present invention is to provide a synthetic silica glass optical material which exhibits excellent transmittance as well as durability for high output power vacuum ultraviolet rays, being emitted from, for example, ArF excimer lasers and Xe.sub.2 excimer lamps, and to provide a method for producing the same. A synthetic silica glass optical material for high output power vacuum ultraviolet rays made from ultra high purity synthetic silica glass for use in the wavelength region of from 165 to 195 nm, containing OH groups at a concentration of from 5 to 300 wtppm with a fluctuation width in OH group concentration (.DELTA.OH/cm) of 10 wtppm or less, containing hydrogen molecules at a concentration of from 1.times.10.sup.17 to 1.times.10.sup.19 molecule/cm.sup.3 with a fluctuation width in hydrogen molecule concentration (.DELTA.H.sub.2 /cm) of 1.times.10.sup.17 molecule/cm.sup.3 or lower, and containing chlorine at a concentration of 50 wtppm or lower.

Abstract: This invention relates to an optical member made of highly transparent, high-purity synthetic silica glass, to a method for manufacturing a blank or an optical member of such glass, and to the optical members themselves. The optical members have an absolute refractive index, n.sub.d, of 1.460 or more and a hydrogen molecule concentration of at least 5.times.10.sup.16 molecules/cm.sup.3 uniformly distributed throughout the glass and are particularly well suited for use in apparatus in which they are exposed to a high-power laser beam such as that produced by an excimer laser.

Abstract: The invention relates to lenses, prisms or other optical members which are subjected to high-power ultraviolet light having a wavelength of about 360 nm or less, or ionizing radiation, particularly optical members for use in laser exposure apparatus for lithography, and to blanks for such optical members. The homogeneity of the refractive index distribution and the resistance to optical deterioration when the optical members are exposed for a long period of time to short wavelength ultraviolet light from a laser beam are improved. The optical members are made of high-purity synthetic silica glass material containing at least about 50 wt. ppm of OH groups, and are doped with hydrogen.

Abstract: The invention relates to lenses, prisms or other optical members which are subjected to high-power ultraviolet light having a wavelength of about 360 nm or less, or ionizing radiation, particularly optical members for use in laser exposure apparatus for lithography, and to blanks for such optical members. The homogeneity of the refractive index distribution and the resistance to optical deterioration when the optical members are exposed for a long period of time to short wavelength ultraviolet light from a laser beam are improved. The optical members are made of high-purity synthetic silica glass material containing at least about 50 wt. ppm of OH groups, and are doped with hydrogen.