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:
This invention provides a black synthetic quartz glass, which has a high level of emissivity in a far infrared region, has excellent light shielding properties, can maintain the same metal impurity level as a synthetic quartz glass, has high-temperature viscosity properties comparable with natural quartz glass, and, at the same time, has electroconductive properties on its surface, and a process for producing the black synthetic quartz glass. The black synthetic quartz glass has an emissivity of not less than 0.8 in a far infrared region, a light transmittance of not more than 10% at 200 to 10000 nm in a thickness of 1 mm, a total metal impurity concentration of not more than 1 ppm, and a viscosity of not less than 10 11.7 poise at 1280°C. Preferably, the content of carbon is more than 30 ppm and not more than 50000 ppm and the concentration of hydroxyl group is not more than 10 ppm.
Abstract:
첫 번째로, 불순물이 적고 천연 석영 유리와 동등 이상의 고온 점도 특성을 가지고, 고온 환경하에서도 변형하기 어려운 합성 석영 유리의 제조 방법, 특히 발포가 없고 치밀한 고내열성 합성 석영 유리의 제조 방법을 제공한다. 두 번째로, 본 발명의 제조 방법에 의하여 용이하게 얻어지는 고내열성 합성 석영 유리체, 특히 발포가 없고 치밀하며, 적외선 흡수율 및 방출율이 높고, 또 알칼리금속 확산 방지 효과가 대단히 높은 투명 또는 흑색 유리체를 제공한다. 245nm의 흡수 계수가 0.05cm -1 이상인 고내열성 석영 유리체를 제조하는 방법으로, 실리카 다공질체를 환원 처리한 후, 소성해서 치밀한 유리체로 하도록 했다. 고내열성 합성 석영 유리, 실리카 다공질체, 환원 처리, 치밀한 유리체, 발포, 고온 점도 특성, 석영 유리 지그, 투명 석영 유리, 흑색 석영 유리, 실라잔, 휘발성 규소화합물
Abstract:
A method for producing a synthetic quartz glass having an absorbing coefficient at 245 nm of 0.05 cm-1 or greater, which comprises subjecting a porous silica material to a reducing treatment, and then firing the resultant product, to thereby form a dense glass article; and a transparent or black synthetic quartz glass which has a reduced content of impurities, exhibits a high temperature viscosity characteristics being the same as or superior to those of a natural quartz glass, is less prone to deformation even in a high temperature atmosphere, exhibits high absorbance and high emission rate for an infrared ray, and exhibits extremely high effect for the prevention of diffusion of an alkali metal, in particular, a dense and highly heat-resistant synthetic quartz glass containing no bubbles. The method allows the production of the above synthetic quartz glass with ease.
Abstract:
The invention relates to a method for producing a silica glass article, involving method steps i.) providing a silica granulate, ii.) forming a glass melt from the silica granulate, and iii.) forming a silica glass article from at least some of the glass melt, step i.) comprising step I. providing a silica powder and step II. processing the powder to obtain a silica granulate, the processing involving spray drying a silica suspension using a nozzle. The nozzle has a contact surface to the suspension composed of glass, plastic or a combination thereof. The invention further relates to a silica glass article that can be obtained by said method. The invention also relates to the production of a silica granulate. The invention finally relates to an optical waveguide, an illuminant and a molded article, each of which can be obtained by further processing the silica glass article.
Abstract:
The invention relates to a method for producing a silica glass body, comprising the method steps: i.) providing silicon dioxide particles ii.) forming a glass melt from the silicon dioxide particles in a furnace and iii.) forming a silica glass body from at least one portion of the glass melt, wherein the furnace has a gas outlet, through which gas can be removed from the furnace and the dew point of the gas exiting the furnace through the gas outlet is less than 0°C. The invention also relates to a silica glass body that can be obtained by this method. In addition, the invention relates to a light guide, a lighting means and a shaped body, each of which can be obtained by subsequent processing of the silica glass body.
Abstract:
The invention relates to a method for producing a silica glass article, involving method steps i.) providing a silica granulate which is made from pyrogenic silica powder and has a BET surface area ranging from 20 to 40 m2/g, ii.) forming a glass melt from the silica granulate in a furnace, and iii.) forming a silica glass article from at least some of the glass melt, the furnace including at least a first chamber and another chamber which are connected to one another by a passage, the temperature in the first chamber being lower than the temperature in the other chamber. The invention further relates to a silica glass article that can be obtained by said method. The invention also relates to an optical waveguide, an illuminant and a molded article, each of which can be obtained by further processing the silica glass article.
Abstract:
Um bekannte Verfahren zur Herstellung eines Verbundkörpers mit einer ersten Schicht aus hochkieselsäurehaltigem Werkstoff mit einer Zusatzkomponente in einer ersten Konzentration, verbunden mit einer zweiten Schicht aus hochkieselsäurehaltigem Werkstoff mit einer Zusatzkomponente in einer von der ersten Konzentration abweichenden zweiten Konzentration, wobei die erste und die zweite Konzentration größer oder gleich Null ist, dahingehend zu optimieren, dass ein mechanisch und thermisch stabiler Verbundkörpers kostengünstig hergestellt werden kann und großflächige Fügeverbindungen durch Verschweißen realisierbar sind, wird erfindungsgemäß ein Verfahren vorgeschlagen, das folgende Verfahrensschritte umfasst: (a) Herstellen eines eine freie Oberfläche aufweisenden ersten Schlickerschicht unter Einsatz einer ersten Schlickermasse, die ein erstes Dispergiermittel und darin dispergiert erste SiO 2 -Teilchen und die Zusatzkomponente in einer ersten Konzentration enthält, (b) Bereitstellen einer zweiten Schlickermasse, die ein zweites Dispergiermittel und darin dispergiert zweite SiO 2 -Teilchen und die Zusatzkomponente in einer zweiten Konzentration enthält, die sich von der ersten Konzentration unterscheidet, (c) Bildung eines Verbundkörper-Vorprodukts durch Auftragen der zweiten Schlickermasse auf die freie Oberfläche der ersten Schlickerschicht, und (d) Erhitzen des Verbundkörper-Vorprodukts unter Bildung des Verbundkörpers.