Abstract:
A synthetic silica glass article made by hydrolyzing an alkoxysilane and thermally sintering the resulting silica; this synthetic silica glass article has a viscosity of not lower than 10.sup.10 poise at 140.degree. C., and contains, as metallic impurities, less than 1 ppm at Al, less than 0.2 ppm of Fe, less than 0.2 ppm of Na, less than 0.2 ppm of K, less than 0.01 ppm of Li, less than 0.2 ppm of Ca, less than 0.02 ppm of Ti, less than 0.01 ppm of B, less than 0.01 of P, less than 0.01 ppm of As.
Abstract:
In the manufacture of preforms for optical fibres, the materials of the core (.alpha.) and of the light-conducting cladding layer (.beta..sub.1) are previously deposited from the gaseous phase. Deposition time is here considerably reduced in that only the materials of the core (.alpha.) and a part of the light-conducting cladding layer (.beta..sub.1) are deposited from the gaseous phase and the remaining light-conducting cladding material (.beta..sub.2 +.beta..sub.3) is supplied as pre-formed tubes of cladding material.
Abstract:
A method for forming high purity silica articles. The high purity silica articles can be particularly suitable for forming packaging such as packaging for pharmaceutical applications. The method for forming high purity silica articles can comprise, in one embodiment, (a) forming a fused quartz melt from a SiO2 raw material; (b) forming a quartz tube from the fused quartz melt; (c) treating the quartz tube with an acid composition; (d) heat treating the quartz tube subsequent to treating with the acid composition; and (e) optionally treating the quartz article with an acid composition subsequent to the heat treating operation. The method can enhance the purity of silica glass articles and products made therefrom.
Abstract:
The production of quartz glass granules comprises the granulation of pyrogenically produced silicic acid and the formation of a SiO2 granulate (9), the drying and cleaning of the SiO2 granulate (9) by heating in an atmosphere containing halogen, and the vitrification of the SiO2 granulate (9) under a treatment gas which contains at least 30% by volume of helium and/or hydrogen. This process is time-consuming and expensive. In order to provide a method which, starting from a porous SiO2 granulate (9), allows the cost-effective production of dense, synthetic quartz glass granules suitable for melting bubble-free components of quartz glass, the invention proposes that the cleaning and vitrification of the SiO2 granulate (9) and a post-treatment of the vitrified quartz glass granules are carried out in each case in a rotary tube (6) of a rotary kiln (1), said rotary tube rotating about a central axis (7), wherein the rotary tube (6) comprises an inner wall made of a ceramic material during vitrification, and wherein the vitrified quartz glass granules are subjected to a post-treatment during a treatment period of at least 10 minutes in an atmosphere which contains less than 20% of helium or hydrogen at a treatment temperature of 300° C. or more.
Abstract:
The present invention relates to an optical member for deep ultraviolet having a wavelength of 250 nm or shorter, containing a synthetic silica glass which does not substantially contain a halogen element, has a maximum OH group content of less than 10 ppm by weight, has contents of ODC (oxygen deficient centers) and E-prime center of each less than 1×1014 cm−3, does not substantially contain SiH and peroxy linkage, and has a fictive temperature of 1,050° C. or lower.
Abstract:
A method of molding a synthetic silica glass molded body by accommodating a synthetic silica glass block in a mold provided with a pressing portion, and by pressing the block while heating, the method including: washing the synthetic silica glass block so that a concentration of copper which is present on the surface of the synthetic silica glass block is 2 ng/cm2 or less; heating high purity carbon powders with a content of copper and aluminium; heating the mold at a temperature condition of 1700° C. to 1900° C.; applying the powders before accommodating the block in the mold; and molding the block in a predetermined form by pressing the block while heating within a hold temperature range of 1500° C. to 1700° C., after accommodating the washed block in the mold.
Abstract translation:一种合成石英玻璃成型体的成型体,其通过将合成石英玻璃块容纳在具有按压部的模具中,并且在加热的同时加压块而成型,其特征在于,包括:洗涤合成石英玻璃块,使铜 存在于合成石英玻璃块的表面上的浓度为2ng / cm 2以下; 加热含有铜和铝的高纯度碳粉; 在1700℃至1900℃的温度条件下加热模具。 在将块容纳在模具中之前施加粉末; 并且在将洗涤的块体容纳在模具中之后,在1500℃至1700℃的保持温度范围内加热的同时通过压制块将模块成型为预定形式。
Abstract:
A method of molding a synthetic silica glass molded body by accommodating a synthetic silica glass block in a mold provided with a pressing portion, and by pressing the block while heating, the method including: washing the synthetic silica glass block so that a concentration of copper which is present on the surface of the synthetic silica glass block is 2 ng/cm2 or less; heating high purity carbon powders with a content of copper and aluminium; heating the mold at a temperature condition of 1700° C. to 1900° C.; applying the powders before accommodating the block in the mold; and molding the block in a predetermined form by pressing the block while heating within a hold temperature range of 1500° C. to 1700° C., after accommodating the washed block in the mold.
Abstract translation:一种合成石英玻璃成型体的成型体,其通过将合成石英玻璃块容纳在具有按压部的模具中,并且在加热的同时加压块而成型,其特征在于,包括:洗涤合成石英玻璃块,使铜 存在于合成石英玻璃块的表面上的浓度为2ng / cm 2以下; 加热含有铜和铝的高纯度碳粉; 在1700℃至1900℃的温度条件下加热模具。 在将块容纳在模具中之前施加粉末; 并且在将洗涤的块体容纳在模具中之后,在1500℃至1700℃的保持温度范围内加热的同时通过压制块将模块成型为预定形式。
Abstract:
Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
Abstract:
First of all, there is provided a production process of a synthetic quartz glass which has less impurity, has a high-temperature viscosity characteristic equal to or more than that of a natural quartz glass, and hardly deforms even in a high-temperature environment, and especially a production process of a highly heat resistant synthetic quartz glass which is free from the generation of bubbles and is dense. Secondly, there is provided a highly heat resistant synthetic quartz glass body which is easily obtained by the production process of the present invention, and especially a transparent or black quartz glass body which is free from the generation of bubbles, is dense, has high infrared absorption rate and emission rate, and has an extremely high effect for preventing diffusion of alkali metal. The process is a process of producing a highly heat resistant quartz glass body having an absorption coefficient at 245 nm of 0.05 cm−1 or more, and the silica porous body was subjected to a reduction treatment, followed by baking, thereby forming a dense glass body.
Abstract:
Granules based on silicon dioxide and having the properties: Average grain size:10 to 120 μm BET surface area:40 to 400 m2/g Pore volume:0.5 to 2.5 ml/g Pore size distribution:less than 5% of the total pore volume exists of pores with a diameter