Abstract: A method for producing an optical quartz glass for use in excimer lasers, comprising a step of forming a porous silica preform by depositing silica in a soot-like form formed by flame hydrolysis of a high-purity volatile silicon compound, followed by a step of vitrifying said porous silica preform into transparent glass in an atmosphere containing water vapor and hydrogen, and a vertical type heating furnace for carrying out the production method therein.

Abstract: An alkali-free glass applicable to a light transparent glass substrate in a liquid crystal display essentially consists, by weight, of basic elements of 40-70% SiO2, 6-25% Al2O3, 5-20% B2O3, 0-10% MgO, 0-15% CaO, 0-30% BaO, 0-10% SrO, and 0-10% ZnO, and a fining agent of a combination of 0.05-3% Sb2O3 and at least one of 0.05-2% SnO2 and 0.005-1% Cl2, which fining agent makes the resultant glass free from bubbles without the use of toxic As2O3 which has been known as the fining agent in the art.

Abstract: A pressure pad array is used to float glass sheets from a glass heating furnace to a ring mold in a press bending station. The pressure pads have transversely spaced, longitudinally-extending slotted nozzles angled towards one another to provide a static pressure area for floating the glass sheet. The slotted nozzles are aligned with the direction of glass sheet travel and the space between adjacent pressure pads is covered by a spacer baffle to generate additional static pressure flotation areas. The static pressure areas formed by the slotted nozzles generally produce uniform pressure profiles extending longitudinally and transversely against the sheet's underside to stably float the glass sheets on a heated gas cushion.

Abstract: A silica glass forming method is a method of pressing a synthetic silica bulk having at least a set of opposed surfaces, on the surfaces under a high temperature condition by a presser, wherein an elastic member with permeability is placed between the presser and the surfaces of the synthetic silica bulk pressed by the presser and wherein the synthetic silica bulk is pressed through the elastic member by the presser. This method is able to reduce bubbles remaining inside the synthetic glass formed product after the forming to a sufficiently small amount. Therefore, it becomes feasible to provide the method that permits high-yield production of silica glasses with excellent optical characteristics.

Abstract: A method and apparatus is described, with which individual rectangular glass panes of thickness between 0.03 mm and 2 mm can be cut from a glass band (2) drawn vertically from a hot forming device (1) in an in-line process with reduced rejects and reduced waste. The method provides that the glass band (2) drawn vertically downward through a vertical zone is cooled below a lower cooling point of the glass and subsequently is deflected through a bending zone (3b) with a bending radius between 0.1 m and 4 m into a horizontal zone (3c) in which it is horizontally oriented. The vertical alignment of the glass band (2) in the vertical zone (3a) is continuously monitored. At least one cutting process is performed on the horizontally oriented glass band (2) in the horizontal zone (3c). The device (20) for monitoring the vertical alignment of the glass band (2) includes at least three sensors (22a, 22b, 22c; 22a′, 22b′, 22c′) that detect the glass edges These sensors can be mechanical rollers.

Abstract: This invention provides a belt for bending a glass sheet without surface defects caused by roller marks, belt junctions or belt deformations. A strip of heat-resistant member is joined together while the ends of the heat-resistant member are arranged so that they are not exposed at the surface defined by an endless track for bending the glass sheet. Alternatively, fitting portions are arranged along the endless track, and the glass sheets are bent while these fitting portions prevent a deformation of the belt. Bent glass sheets can be manufactured efficiently and without surface defects by bending the sheets while conveying them with such a belt.

Abstract: In a method of producing a glass gob by continuously dropping a molten glass 9 from a nozzle 2 in a dropping direction, a gas flow 20 is caused to continuously flow in the dropping direction along an outer peripheral surface of the nozzle 2 at a predetermined flow rate. The gas flow 20 applies a wind pressure to the molten glass 9 appearing from a nozzle end 2a of the nozzle 2 to drop the molten glass 9.

Abstract: A synthetic quartz glass for optical use, to be used by irradiation with light within a range of from the ultraviolet region to the vacuum ultraviolet region, which contains fluorine, which has a ratio of the scattering peak intensity of 2250 cm−1 (I2250) to the scattering peak intensity of 800 cm−1 (I800), i.e. I2250/I800, of at most 1×10−4 in the laser Raman spectrum, and which has an absorption coefficient of light of 245 nm of at most 2×10−3 cm−1.

Abstract: The apparatus serves for pushing at least one of two hollow glass articles from a dead plate of a glass forming machine onto a conveyor belt. A pusher serves for this purpose, and includes a base portion and, for each glass article which is to be pushed, at least one thrust finger extending transversely to the base portion. Each thrust finger defines with the base portion a pocket for receiving the glass article. A nozzle is arranged in the region of a corner of the associated pocket. From each nozzle compressed air can be blown such that a pressure below atmospheric pressure which draws the glass article into the pocket is created between the pusher and the glass article. The compressed air is blown from the corner out between the base portion and the glass article.

Abstract: The method for converting harmful polychlorinated biphenyl (PCB) oil into a resource includes chemical decomposition treatment, pelletizing treatment and thermal decomposition treatment. The chemical decomposition treatment uses a decomposing agent including calcium oxide powder coated with a vegetable oil and quartz porphyry powder, causes a decomposing action of CaO and far-infrared rays emitted from quartz porphyry, to act onto polychlorinated biphenyl oil, and decomposes the polychlorinated biphenyl oil into powder including a metal salt. The pelletizing treatment hardens the powder into pellets. The thermal decomposition treatment melts the pellets and glass cullet at a temperature above the thermal decomposition temperature of the PCBs for molten integration of the pellets and glass cullet as slag. The slag is cooled and the solid substance can be widely used as various types of construction materials and agricultural materials.

Abstract: A method and apparatus are disclosed for the manufacture of an optical fiber preform having incorporated therein a comparatively high concentration of rare earth dopant material, and which thus can be drawn and processed into an optical fiber having low numerical aperture, low core attenuation, and high pumping power absorption. The high concentrations of rare earth dopant material are accomplished through either the “hybrid vapor processing” (HVP) method or a “hybrid liquid processing” (HLP) method, each capable of being practiced in combination or independently of one another. The HVP method involves the vaporization of a rare earth halogen by the exposure thereof to a sufficiently elevated temperature, independently, or contemporaneously with the transport of the resultant rare earth halogen laden vapor, into a glass forming oxidation reaction zone on a flowing stream of essentially an unreactive inert gas, such as helium.

Abstract: A method of heating low emissivity glass sheet for subsequent processing. The glass sheet is loaded onto a longitudinally extending conveyor and oriented such that the lengthwise edge of the sheet is parallel to the length of the conveyor and the direction of conveyance of the glass sheet. The sheet is conveyed into a heating chamber. The glass sheet is then convectively heated in a specified sequence along the entire length of the glass sheet at selected areas measured along the width by creating a downward flow of heated air proximate the selected areas.

Abstract: The invention relates to a cigarette paper having a low total filler content, 20% by weight of the paper or less, a proportion of the filler being a filler capable of effecting visible sidestream smoke reduction. The basis weight of the paper is about 30 g m−2 or more. Smoking articles made with such papers provide a synergistic sidestream smoke component reduction when compared with control cigarettes. Papers according to the invention with the addition of various burn additives are also described.

Abstract: A laser processing method for removing glass by melting, evaporation or ablation from sheet-like glass substrate for forming microscopic concavities and convexities. Diffraction grating and planar microlens array obtained thereby.

Abstract: A furnace particularly for heat treatments of glass sheets, comprising a longitudinally-elongated chamber which contains roller conveyor elements for the glass sheets. The furnace comprises irradiation-heating elements combined with first and second elements for heating by forced air convection in which the air temperature is controlled by adjusting its circulation rate, the elements being located respectively above and below the conveyor elements and therefore above and below the sheets being treated.

Abstract: A heat-resistant pipe is arranged so as to traverse below a glass ribbon in a float bath of molten tin, and bubbles emanate from the heat-resistant pipe, thereby making the bottom surface (which is in contact with the tin) uneven. Alternatively, the bottom surface is made uneven with a roller for lifting the glass ribbon out of the float bath into an annealing furnace. In addition to these operations for making the glass surface uneven, a film can be applied to the top face of the glass ribbon (i.e. the surface that is not in contact with the tin) by CVD, supplying a mixed gas of raw material from coaters. Thus, the invention makes it possible to manufacture a glass sheet having an uneven surface efficiently, using a technique for processing the surface of a glass sheet that is suitable for a production line for float glass.

Abstract: The present invention discloses novel methods for fabricating glass articles, particularly optical fiber glass preforms, which may contain alumina, yttrium, lanthanum, erbium, or other rare earth metals as dopants. The glass articles made in accordance with the present invention exhibit radially uniform dopant profiles relative to conventional dopant methods. In addition, the overall concentration of the dopant is increased relative to analogous dopant methods.

Abstract: The wet film thickness during spraying of the coating composition onto the substrate is preferably adjusted such that it is greater by a factor of at least 8 than the target dry film thickness.

Abstract: Fused silica boules (19) having improved radial homogeneity are produced by controlling the air flow around the boule (19) during its formation. The boule is formed in a cup-like containment vessel (13) which collects silica particles from a plurality of burners (14). The containment vessel (13) rotates and oscillates relative to the burners (14) as the boule (19) is formed. The containment vessel (13) is bounded by a cup-like containment wall (22), and a shadow or air flow wall (130) is spaced apart from and surrounds the containment wall (22) forming a gap or air flow passage (175) therebetween. A radially-outwardly extending deflecting wedge portion (23) is formed at the upper extent of the containment wall (22) and at an outlet end of flow passage (175).

Abstract: The invention pertains to a stirrer apparatus for glass melts. A stirring element and a stirrer shaft are provided, each comprised of a metal or a metal alloy having a high melting point temperature. A drive shaft for the stirring element comprises a different metallic material, for example an ODS alloy on the basis of iron or nickel. The junction between the stirrer shaft and the drive shaft is located approximately in the region in which the level of the surface of the glass melt is located during use. The end portion of the drive shaft or the end portion of the stirrer shaft, which can be covered by the melt during use, are isolated by a platinum casing.