533 results about "Vitreous Bodies" patented technology

Numerous applications for hollow glass bodies made from low melting glass material require an increase in the chemical resistance of the interior surface of the glass body. In order to avoid a disadvantageous de-alkalizing process the hollow glass body must be provided with an interior coating in a comparatively expensive prior art process. In an improved process according to the invention a glass tube acting as a semifinished product from which the hollow glass body is made is provided with an interior coating of oxide material, preferably SiO2, Al2O3, TiO2 or mixtures thereof, having a predetermined coating thickness according to the required chemical resistance or working conditions for forming the glass body and then the hollow glass body is made from the glass tube. The coating is advantageously provided by means of a PICVD process.

PCT No. PCT/EP97/03818 Sec. 371 Date Mar. 3, 1998 Sec. 102(e) Date Mar. 3, 1998 PCT Filed Jul. 17, 1997 PCT Pub. No. WO98/03440 PCT Pub. Date Jan. 29, 1998In a known process for the production of quartz glass bodies, SiO2 particles are deposited of the mantle surface of a cylindrical carrier rotating about its longitudinal axis, forming an elongated, porous preform, where the SiO2 particles are formed in a plurality of flame hydrolysis burners which are arranged in at least one burner row parallel to the longitudinal axis of the carrier and are moved at a preset translational speed forward and back between turnaround points at which points their direction of movement is reversed, and in which process the preform is sintered. In order to make available on this basis an easily accomplished process that makes it possible to manufacture a preform which is largely free of localized density variations, the invention proposes on the one hand that the base value of the surface temperature of the preform being formed be kept in a range between 1,050 DEG C. and 1,350 DEG C., that the average peripheral velocity of the preform be kept in the range between 8 m/min and 15 m/min and the average translational velocity of the burner row be kept in a range between 300 mm/min and 800 mm/min. On the other hand, the object is also accomplished according to the invention and on the basis of the known process in that in the area of the turnaround points (A, B) the peripheral velocity of the preform being formed is increased and/or the flame temperature is lowered and/or the distance of the burners from the preform surface is changed.

A method of manufacturing an optical fiber, characterized by comprising the steps of forming a glass body having a core, forming a glass tube constituting a clad portion, inserting the glass body into the glass tube, forming the glass body integrally with the glass tube, finishing at least the extraction side end part of the glass tube in a tapered shape and washing the outer surface of the glass tube, characterized in that a difference between the outer diameter of the glass body and the inner diameter of the glass tube is 1.0 to 10.0 mm, and the inner diameter of a support tube fitted to one end of the glass tube is increased more than that of the glass tube or the extraction side end part of the glass tube is sealed with a tapered part provided at least on the inner surface thereof and a spacer is installed so that a clearance between the outer diameter of the glass body and the inner diameter of the glass tube becomes generally constant in the longitudinal direction.

The invention relates to a method for manufacturing a glass tube with a coated inner surface by drawing a glass melt (5) to a bag (8) of softened glass and hot forming to a glass tube (9). During the process a substance is introduced into the bag (8) of softened glass. According to the invention the substance is introduced as an aerosol and the inner surface is coated by means of the substance during the hot forming. The method permits economical internal coating with a continuous glass drawing method. The use of aggressive chemical substances for internal coating can be dispensed with according to the invention. As a result, for example, internally coated glass tubes with improved hydrolytic resistance can be manufactured. The invention also relates to a suitable apparatus for manufacturing internally coated glass tubes and the use of glass tubes manufactured by this means for further processing to a hollow, internally coated formed glass body, for example, as primary packaging in the pharmaceuticals field.

A method for laser patterning of a glass body, the method comprising the steps of:

• (i) providing a laser, said laser having an output beam at a laser wavelength λ;
• (ii) providing a glass body having optical density at of at least 1.5/cm at said wavelength;
• (iii) directing said laser output beam to (a) impinge on the glass body without ablating said glass, and (b) heat the glass body at a location proximate to said laser output beam so as to form a swell at this location; and
• (iv) etching this location.

It is to provide a silica glass containing TiO₂, having a wide temperature range wherein the coefficient of thermal expansion is substantially zero.

A silica glass containing TiO₂, which has a TiO₂ concentration of from 3 to 10 mass %, a OH group concentration of at most 600 mass ppm and a Ti³⁺ concentration of at most 70 mass ppm, characterized by having a fictive temperature of at most 1,200° C., a coefficient of thermal expansion from 0 to 100° C. of 0±150 ppb/° C., and an internal transmittance T_400-700 per 1 mm thickness in a wavelength range of from 400 to 700 nm of at least 80%. A process for producing a silica glass containing TiO₂, which comprises porous glass body formation step, F-doping step, oxygen treatment step, densification step and vitrification step.

Process for preparing glass-ceramic body including the steps of providing a basic glass body and subjecting the basic glass body to a thermal treatment whereby a crystalline phase embedded in a glass matrix is formed. The basic glass body is made of a composition comprising 65 to 72 wt-% SiO₂, at least 10.1 wt-% Li₂O and at least 10.1 wt-% Al₂O₃ based on the total weight of the composition, the proportion of Li₂O to Al₂O₃ being from 1:1 to 1.5:1. The thermal treatment involves a nucleation step followed by several crystallization steps at different temperatures, whereby at least two different crystalline phases are formed.

The invention includes an improved quartz glass body, especially an improved quartz glass crucible for melting non-metals, non-ferrous metals, or silicon, and a method and casting mold for making it The quartz glass body is made by a method in which a quartz glass-water mixture is supplied to a casting mold comprising an outer part and an inner part, dried in the mold, and put under an overpressure during the drying. Later a resulting green glass body is removed from the mold. At least a portion of the shaping surfaces of the inner part of the mold are surfaces of a water-impermeable substance. The method provides a cast body with a reduced tendency to crack and with a smaller open porosity.

A luminescence conversion LED having a radiation emitting chip that is connected to electrical connections and is surrounded by a housing that comprises at least a basic body and a cap, the chip being seated on the basic body, in particular in a cutout of the basic body, and the primary radiation of the chip being converted at least partially into longer wave radiation by a conversion element, wherein the cap is formed by a vitreous body, the conversion means being contained in the vitreous body, the refractive index of the vitreous body being higher than 1.6, preferably at least n=1.7.

A silica glass containing TiO₂, which has a fictive temperature of at most 1,200° C., a F concentration of at least 100 ppm and a coefficient of thermal expansion of 0±200 ppb/° C. from 0 to 100° C.

A process for producing a silica glass containing TiO₂, which comprises a step of forming a porous glass body on a target quartz glass particles obtained by flame hydrolysis of glass-forming materials, a step of obtaining a fluorine-containing porous glass body, a step of obtaining a fluorine-containing vitrified glass body, a step of obtaining a fluorine-containing formed glass body and a step of carrying out annealing treatment.

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.

The apparatus integrated with ceramic bushing/s for manufacturing mineral/basalt fibers from natural basalt rocks is disclosed. The apparatus and the ceramic bushing/s are integrated into one unit capable provide all operations which are needed: melt basalt rock materials, homogenize basalt glass body suitable for forming fibers to be drawn/attenuated into continuous fibers and gathered into a strand of elemental fibers from 7 to 20 micrometers (μm) in diameter. Also the coarse fibers at the diameters from 20 μm to 100 micrometers (μm) having amorphous structural state which exhibit ductile/flexible properties. The ceramic bushing/s are designed to eliminate precious Pt, Rd metals using instead corrosion resistant ceramic materials to reduce basalt fiber products cost and to increase its commercial compatibility when compared to the other fibers currently been on the market in reinforced concrete/composite applications, including Three Dimension Fiber Reinforced Concrete-3D FRC.

The present invention relates to poisonous waste treating method and apparatus, and belongs to the field of waste treating technology. The poisonous waste treating apparatus is plasma apparatus comprising a furnace body, a main graphite electrode and an auxiliary graphite electrode connected to the cover of the furnace body, carrier gas supplier connected to the main graphite electrode, a feeder, a vitreous body exhausting heat pump, a metal melt heat pump, a crucible inside the furnace body, a lower electrode in the bottom of the furnace body, a liquid level sensor connected to the sensor controller, and a tail gas exhausting system connected to the furnace body. It is used in treating polychlorinated biphenyl and other high dangerous waste through instantaneous high temperature, and has no secondary pollution, capacity of recovering high energy gas, and capacity of recovering metals.

A biphasic nanoporous vitreous carbon material with a cementitious morphology characterized by presence of non-round porosity, having superior hardness and tribological properties, as useful for high wear-force applications. The biphasic nanoporous vitreous carbon material is produced by firing, under inert atmosphere, of particulate vitrified carbon in a composition containing (i) a precursor resin that is curable and pyrolyzable to form vitreous carbon and, optionally, (ii) addition of one or more of the following: solid lubricant, such as graphite, boron nitride, or molybdenum disulfide; a heat-resistant fiber reinforcement, such as copper, bronze, iron alloy, graphite, alumina, silica, or silicon carbide; or one or more substances to improve electrical conductivity, such as dendritic copper powder, copper “felt” or graphite flake, to produce a superior vitreous carbon that is useful alone or as a continuous phase in reinforced composites, in relation to conventional glassy carbon materials.

In order to avoid deposition of evaporating alkali compounds on an inner surface of a hollow glass body during thermal processing to form a glass container from the hollow glass body, an overpressure is provided in the hollow glass body during the thermal processing. Either rinsing the hollow glass body with a gas, such as air, or at least partially closing the glass body at one end so that sufficiently rapid pressure equilibration is avoided, can provide this overpressure. The glass containers made by these methods are especially suited for food or pharmaceuticals because they have a reduced alkali release from their inner surfaces, for example at most about 2.0 mg/l sodium oxide.

The invention relates to lead-free glass powders with low melting point for sealing of metal or alloy and preparation methods thereof. The glass powder comprises P2O5, ZnO, Al2O3, SiO2, MgO, MnO2, Li2O, WO3, CaF2, Na2O, K2O and CaO. The preparation thereof is divided into the following steps: (1) raw materials are drawn and fully mixed according to weight proportions to make into mixed materials; (2) the mixed materials are heated and melted for 30 minutes to two hours under a temperature ranging from 1000 DEG C to 1350 DEG C; (3) the melted glass liquid is cooled and cured into glass body. The glass powder not only has comparatively ideal heat expansion coefficient, softening temperature and chemical stability but also has simple preparation process, straightforward operation and low cost, which is applicable to the sealing of glass, ceramic, metal and semiconductor and in particular applicable for the sealing of metals of molybdenum family and tungsten family or alloy such as kovar alloy. Also the glass powder is competitive in lead-free production and has wide market development prospect.

The invention is directed to the detection and imaging of the internal geometry of the eye, particularly of the important components for imaging in the eye such as the cornea, lens, vitreous body and retinal surface, by multichannel short coherence interferometry. A method and arrangement for obtaining topograms and tomograms of the eye structure by many simultaneously recorded interferometric depth scans through transversely adjacent points in the pupil using spatially coherent or spatially partially coherent light sources. The depth scan is carried out by changing the optical length of the interferometer measurement arm by means of a retroreflector. By continuously displacing the retroreflector, the z-position of the light-reemitting point in the eye can be determined by means of the occurring interference. It is possible to record depth scans simultaneously through the use of spatially coherent or spatially partially coherent light beams comprising a plurality of partial beams.

The present invention is directed to a method for making fused silica glass. A liquid, preferably halide-free, silicon-containing compound capable of being converted by thermal oxidative decomposition to SiO2 is provided and introduced directly into the flame of a combustion burner, thereby forming finely divided amorphous soot. The amorphous soot is deposited on a receptor surface where, either substantially simultaneously with or subsequently to its deposition, the soot is consolidated into a body of fused silica glass. The invention further relates to an apparatus for forming fused silica from liquid, preferably halide-free, silicon-containing reactants which includes: a combustion burner which, in operation, generates a flame; an injector for supplying a liquid silicon-containing compound to the flame to convert the compound by thermal oxidative decomposition to a finely divided amorphous soot; and a receptor surface on which the soot is deposited.

Compositions and methods useful for at least assisting in visualizing vitreous bodies of eyes of humans or animals are provided. Such compositions include a contrast component and a carrier component and are substantially free of any therapeutic agent effective to have pharmacological activity in an eye in which the composition is placed. Methods of using such compositions as visualization devices are also provided.

The object is to provide a vitreous antimicrobial agent that can exhibit excellent antimicrobial properties when added to various types of resins, that has excellent discoloration resistance and hot water resistance, and that can easily be produced at a commercial scale. It is also to provide an antimicrobial resin composition and an antimicrobial product including the vitreous antimicrobial agent.

The present invention relates to a vitreous antimicrobial agent that includes, relative to 100 mass % of total glass components, 0.1 to 2 mass % of Ag₂O, 40.5 to 49 mass % of ZnO, 6 to 9.5 mass % of SiO₂, 30.5 to 39.5 mass % of B₂O₃, 2 to 10 mass % of an alkaline earth metal oxide, and 6 to 7.5 mass % of Na₂O; a vitreous antimicrobial agent comprising, in addition to these, 0.01 to 5 mass % of CeO₂ as necessary; an antimicrobial resin composition that includes the vitreous antimicrobial agent; and an antimicrobial product that includes the vitreous antimicrobial agent.

Sintered materials, especially sintered glasses, produced from pyrogenically produced silicon dioxide which has been processed to silicon granulates in a compacting step, and the use of such granulates in the production of formed glass bodies.

A composition comprises plasmin or an enzymatically equivalent derivative thereof and at least an anti-inflammatory medicament. The composition can be used to effect or induce a controlled posterior vitreous detachment (“PVD”) to prevent, treat, or ameliorate a potential complication of a pathological ocular condition. Such a composition can be administered intravitreally.

The invention discloses an SiO₂—TiO₂ glass, which is preferably made by flame-hydrolysis and which distinguishes itself by increased resistance to radiation, especially in connection with EUV lithography. By purposefully reducing the hydrogen content, clearly improved resistance to radiation and reduced shrinking is achieved.