Abstract: A process which uses sol-gel to process oxide-based monoliths which are virtually free of cracks, without nullifying the desired attributes of the oxide-based monoliths. The method comprises substantially drying a wet porous gel monolith by removing a portion of the liquid from the pores of the gel monolith while the gel monolith remains wet, shrinking in size, and becoming correspondingly more dense, then removing the remaining portion of the liquid from the pores of the gel monolith such that the outer region of the gel monolith is not dried before the inner region of the gel monolith is dried. The gel monolith is substantially dried under conditions in which the liquid evaporation rate is no greater than the pore liquid diffusion rate.

Abstract: The present invention relates to a method for forming an optical device. The method includes providing a glass aggregate. Typically, the glass aggregate is a mixture of fine glass soot particles and coarser ground or milled glass powder. The glass particles are mixed with a liquid to form a slurry which is cast in a mold to form a porous pre-form. Subsequently, the porous pre-form is consolidated into a glass object by heating the pre-form at a relatively high temperature. The method of the present invention produces optical components having substantially no striae. As a result, scattering is substantially reduced when EUV light is reflected from a component produced from the optical blank.

Abstract: The present invention relates to a process of producing a silica glass in which the sol is transported from a mixer to a former under a certain amount of pressure. The transportation path of the sol is vacuumized in order to remove macro bubbles that can be potentially produced while the sol is transported from the mixer to the former. The interior of a piping connecting between the mixer for bearing the sol and the former for forming the gel is maintained in the vacuum state so as to effectively remove the macro bubbles, which can be potentially produced during the transportation of the sol.

Abstract: Porous, ferro- or ferrimagnetic, glass particles are described that selectively bind molecules of interest, especially nucleic acid molecules, under appropriate conditions. Methods of preparing the porous, ferro- or ferrimagnetic, glass particles and their use of identifying or separating molecules of interest are also described. Kits comprising the porous, ferro- or ferrimagnetic, glass particles are also provided.

Abstract: The invention provides a method for efficiently producing, in a low temperature region, a thin film or micro-spherules of a single component type or a multi-component type metal oxide glass, wherein an organic metal compound is subjected to hydrolyzation in a reaction liquid consisting of water and an organic solvent, with halogen ions (F−, Cl−) as a catalyst in the presence of boron ions (B+), followed by dehydration and condensation, after which a reaction product is vitrified at a temperature of 200° C. or below, thereby obtaining the single component type or multi-component type metal oxide glass film (reaction at a pH value between 5.0 and 4.5), or micro-spherules (reaction at a pH value between 8 and 10). Transparent and homogeneous glass film or micro-spherules, which are excellent in the heat-resistance, moisture-resistance, insulating property, gas-barrier property, and ion-migration preventive property, can be obtained in a normal temperature region.

Abstract: Disclosed is a method for controlling a heat treatment in the process of fabricating a high purity silica glass via a sol-gel process using a low temperature heater having an inhalation line and an exhaust line. Accordingly, the method includes the steps of (a) identifying whether or not the diameter of the exhaust line is varied; (b) controlling the mass flow of the process gas according to the changed diameter of the exhaust line in step (a); (c) measuring an exhaust gas velocity discharged through the exhaust line; (d) comparing the exhaust gas velocity measured in the step (c) with the exhaust gas velocity after the scale of the exhaust line is varied; and, (e) repeating steps (b)-(d) if the comparison result in step (d) is different.

Abstract: The invention relates to optical quality glass made by vacuum casting very stable, low viscosity aqueous suspension of submicron silica particles. The suspension is a mixture of silica particles and aqueous ammonia, and is characterized by a solid loading of up to 75 weight percent.

Abstract: An infrared absorption filter consisting of 70 to 98 mol % of SiO2, 1 to 12 mol % of CuO and 1 to 18 mol % of a network modifier oxide than CuO or CdO is provided. A process of fabricating an infrared absorption filter is also provided. The process comprises introducing a divalent copper compound and a compound of a metal species acting as a network modifier oxide in the form of metal ions into a wet gel. The wet gel can be dipped in a dipping solution to precipitate the divalent copper compound and the compound of a metal species acting as the network modifier oxide in the wet gel. The wet gel can be dried and heated, thereby obtaining an infrared absorption glass. The infrared absorption glass can be cut and polished, thereby fabricating a filter.

Abstract: The invention relates to a method for manufacturing optical glasses and coloured glasses with the aid of a fluid phase sintering process from a basic material encompassing at least SiO2 powder as well as additives for reducing the temperature of the fluid phase sintering and/or melting process encompassing the following steps:

Abstract: The use of silica powders having large particle sizes in making sol-gel silica bodies has been found to have important advantages. Among these are higher gel strength, higher silica loading, more rapid aging and drying of the gel, a reduction in the amount of organic additives leading to reduced process time required for organic burn-off, and easier removal of contaminant particles due to their larger size. It was also discovered that spherical particle morphology contributes to the improved properties.

Abstract: The present invention discloses a method for fabricating silica glass using a sol-gel process, which includes a sol forming step for forming a sol by mixing a starting material, deionized water and an additive together; gelation step for gelatinizing the sol after filling a circular mold with the gel produced; gel drying step for separating the gel from the circular mold and drying the gel; setting step for placing the gel inside of a heat chamber and injecting helium gas into the heat chamber; and low heat treatment step for pressurizing and depressurizing an internal pressure of the heat chamber repeatedly for several times.

Abstract: Inorganic porous materials contained in a confined space with at least one dimension of less than 1 mm, which are in liquid tight contact with the walls of said confined space. Preferred as the confined space are capillaries. Articles contained such materials and methods for making them in the confined space are described.

Abstract: A composition for production of silica glass using a sol-gel process is described, comprising silica particles, a dispersing agent, and a solution containing a polymerizable monomer for formation of acrylic resin and a crosslink agent dissolved in distilled water. The polymerizable monomer is n-methylol acrylamide or n-methylol methacrylamide. A method for production of silica glass is described, including the step of adding silica particles and a dispersing agent to a premix solution of the polymerizable monomer for formation of acrylic resin and the crosslink agent dissolved in distilled water.

Abstract: The present invention provides a method of forming a coating including a metalloxane polymer on a substrate. The method according to the invention includes forming a non-aqueous mixture including an alkoxide, a siloxane, and an organo-metallic catalyst, applying the mixture to the substrate, and heating the substrate to cure the coating. The mixture can also comprise one or more fillers including ceramic powders, glass powders, metal powders, and pigments The method can be used to apply coatings to metal, glass, porcelain enamel, ceramic, and polymeric substrates.

Abstract: Pyrogenically produced oxides of metals and/or metalloids doped with erbium oxide, in which the base component is a pyrogenically produced oxide doped with erbium oxide in an amount of 0.000001 to 40 wt %, in which the BET surface of the doped oxide lies between 1 and 1000 m2/g, are produced by feeding an aerosol into a flame, as used for production of pyrogenic oxide, in which an erbium salt solution is used as the starting product for the aerosol, the aerosol being produced by atomization with an aerosol generator, this aerosol is mixed homogeneously before reaction with a gas mixture for flame oxidation or flame hydrolysis, the aerosol-gas mixture is then allowed to react in a flame, and the formed pyrogenic oxides doped with erbium oxide are separated from the gas stream in a known fashion. The pyrogenic oxide of metals and/or metalloids doped with erbium oxide can be used as glass raw material.

Abstract: The present invention is directed to microemulsion techniques for rapidly preparing photochromic glass nanoparticles and to the photochromic glass nanoparticles so prepared. More particularly, the method of the invention comprises the combination of two microemulsions, one containing a water-soluble silver salt and a glass precursor and the other containing a halide salt and an initiator for glass formation, which process rapidly yields silver halide particles. This invention gives nanometer-sized silver halide particles embedded in glass, thus providing photochromic glass nanoparticles without further annealing, or at most mild annealing. These nanoparticles are valuable as added components to any macro-material that one might wish to have photochromic properties. The particles would impart photochromism while not affecting the physical properties of the material.

Abstract: A sol-gel process for producing dry porous gel monoliths, e.g., silica glass monoliths, in which the successive process steps of gelling, aging and drying all occur within a mold formed of a selected porous material, e.g., graphite. The mold is inert to the gel solution and it has sufficient strength to withstand the temperatures and pressures encountered during the process. The mold and gel thereby can remain within a sealed autoclave during these process steps, and mechanical handling of the mold and the gel are minimized. This substantially enhances the process' efficiency. Alternatively, the mold can have a non-porous inner skin to enhance ease of cleaning of the mold, and of removal of the gel.

Abstract: The invention allows the fabrication of small, dense, highly polished spherical beads of hexagonal ferrites with selected compositions for use in nonreciprocal microwave and mm-wave devices as well as in microwave absorbent or reflective coatings, composites, and the like. A porous, generally spherical bead of hydrous iron oxide is made by a sol-gel process to form a substantially rigid bead having a generally fine crystallite size and correspondingly finely distributed internal porosity. The resulting gel bead is washed and hydrothermally reacted with a soluble alkaline earth salt (typically Ba or Sr) under conditions of elevated temperature and pressure to convert the bead into a mixed hydrous iron-alkaline earth oxide while retaining the generally spherical shape. This mixed oxide bead is then washed, dried, and calcined to produce the desired (BaFe12O19 or SrFe12O19) crystal structure.

Abstract: A planar optical device is formed on a substrate. The device comprises an array of waveguide cores which guide optical radiation. A cladding layer is formed contiguously with the array of waveguide cores to confine the optical radiation to the array of waveguide cores. At least one of the array of waveguide cores and cladding layer is an inorganic-organic hybrid material that comprises an extended matrix containing silicon and oxygen atoms with at least a fraction of the silicon atoms being directly bonded to substituted or unsubstituted hydrocarbon moieties. This material can be designed with an index of refraction between 1.4 and 1.55 and can be deposited rapidly to thicknesses of up to 40 microns. In accordance with another embodiment of the invention, a method for forming a planar optical device obviates the need for a lithographic process.

Abstract: Disclosed is a method for fabricating high-purity silica glass using a sol-gel processing that includes the steps of: (a) mixing deionized water with a monomer and a dimer to prepare an aqueous premix solution; (b) mixing the aqueous premix solution with a fused silica and a dispersion agent; (c) mixing the resulting mixture to form a dispersed sol; (d) aging the dispersed sol at the ambient temperature to stabilize silica particles, and removing air voids from the sol; and, (e) adding a polymerization initiator and a gelation agent to the aged sol.

Abstract: A process for manufacturing an inorganic material-based article comprising the steps of

Abstract: A hydrous silica gel is dehydrated by freezing, thawing, and removing water separated by thawing, thereby yielding silica particles. In addition, the silica particles thus formed is washed and fired, thereby producing a synthetic quartz glass power.

Abstract: Disclosed are silica structure crack detection methods and apparatuses particularly useful in sol-gel fabrication processes. A wave signature of a crack in the silica structure is sensed to indicate that cracking has occurred. Sensing may be by active or passive techniques and may include contact and non-contact methods of monitoring.

Abstract: An improved sol-gel process is disclosed for producing a synthetic silica glass article, in which a sol is formed having a silica loading as high as 34 to 40%. This high loading is achieved by introducing an aqueous colloidal silica suspension into a silicon alkoxide solution and slowly stirring the mixture together, during which time the mixture hydrolyzes and the colloidal suspension is broken down by chemical reaction. This produces a hydrolyzed sol incorporating a suspension of very fine aggregates of colloidal particles, having particle sizes less than about 10 microns. The need for a stabilizing agent and/or continuous ultra-sonicating or violently stirring the sol is eliminated.

Abstract: This invention resides in a process for making silica articles having few or no visible bubbles by sintering silica gels derived from a sol-gel process. The process incorporates control of pH during hydroxylation and gelation, as well as chlorination at temperatures previously considered unsuitable. The process optionally incorporates addition of dispersant to the silica solution.

Abstract: The use of silica powders having large particle sizes in making sol-gel silica bodies has been found to have important advantages. Among these are higher gel strength, higher silica loading, more rapid aging and drying of the gel, a reduction in the amount of organic additives leading to reduced process time required for organic burn-off, and easier removal of contaminant particles due to their larger size. It was also discovered that spherical particle morphology contributes to the improved properties.

Abstract: Cup-shaped porous silica preforms suitable for manufacture of large 24-inch crucibles used in Czochralski crystal-growing furnaces are produced by a unique electrophoretic casting process using a high-purity aqueous silica slip or slurry having a predetermined particle-size distribution, an average particle size of from 6 to 10 microns and a solids content of from 80 to 85 percent by weight. The slurry contains an electrolyte, such as ammonium hydroxide, has a pH of from 7.5 to 8.5, and can be wet milled at a pH of at least 7 in such manner as to provide the micronized silica particles with excellent electrophoretic mobility, thereby providing a superb process for economical mass production of large pure silica preforms using safe voltages, such as 20 to 40 volts. The electrophoretic casting apparatus can be of the type shown in FIGS.

Abstract: The disclosed method of making microstructured optical fiber comprises providing a mold, with a multiplicity of elongate elements extending into the mold and being maintained in a predetermined spatial arrangement with respect to the mold. Silica-containing sol is introduced into the mold and is caused to or permitted to gel, such that a gel body results. After removing the elongate elements from the gel body and removing the gel body from the mold, the gel body is dried, sintered and purified, and the microstructured fiber is drawn from the sintered body.

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: A glass-impregnated, fiber-reinforced ceramic comprises a ceramic matrix having open voids, inorganic fibers embedded in the ceramic matrix in a regular or irregular orientation, and a glass matrix filling up the open voids in the ceramic matrix. The glass-impregnated, fiber-reinforced ceramic is manufactured by a manufacturing method comprising the steps of forming a fiber-reinforced ceramic comprising the ceramic matrix having open voids, and inorganic fibers embedded in the ceramic matrix, impregnating the fiber-reinforced ceramic with a glass precursor solution containing a glass precursor to stop up the open voids of the ceramic matrix with the glass precursor solution, and subjecting the fiber-reinforced ceramic impregnated with the solution to a heat treatment.

Abstract: A silica sol-gel fabrication process is provided which allows improved control of the shrinkage that takes place during the drying of a gel body. In particular, the invention makes it possible to attain extremely low shrinkage through the completion of the drying stage, e.g., below 1% linear shrinkage, in relatively large sol-gel bodies of (dry weight) 1 kg or more, typically 10 kg or more, or even 40 kg or more, compared to the much higher shrinkages typically encountered. Specifically, use of a particular polymeric additive makes it possible for a gel body to experience linear shrinkage at least 55% less than an identical process without the polymeric additive.

Abstract: A composition for production of silica glass using a sol-gel process is described, comprising silica particles, a dispersing agent, and a solution containing a polymerizable monomer for formation of acrylic resin and a crosslink agent dissolved in distilled water. The polymerizable monomer is n-methylol acrylamide or n-methylol methacrylamide. A method for production of silica glass is described, including the step of adding silica particles and a dispersing agent to a premix solution of the polymerizable monomer for formation of acrylic resin and the crosslink agent dissolved in distilled water.

Abstract: A holographic light shaping diffuser (LSD) is formed from a monolithic glass material by recording light shaping structures (sometimes collectively known as “speckle”, particularly when the structures extend into the interior of the diffuser) in the glass material during its formation. A volume LSD may be produced by the photolithographic writing or other imaging of light shaping structures in a photosensitive glass material. Alternatively, a surface LSD may be produced by this imaging process or by embossing light shaping structures onto a high quality optical glass or by embossing a light shaping structures on a glass film layer coated onto a substrate. Both types of diffusers control the angular spread of transmitted light while homogenizing otherwise spatially noisy light sources such as LCDs and filamented light sources and while maintaining damage thresholds consistent with any glass optical element.

Abstract: A sol-gel process for fabricating bulk, germanium-doped silica bodies useful for a variety of applications, including core rods, substrate tubes, immediate overcladding, pumped fiber lasers, and planar waveguides, is provided. The process involves the steps of providing a dispersion of silica particles in an aqueous quaternary ammonium germanate solution—typically tetramethylammonium germanate, gelling the dispersion to provide a gel body, and drying, heat treating, and sintering the body to provide the germanium-doped silica glass.

Abstract: Disclosed are apparatus and method for ultrasonically dispersing a silica sol such as is used in a process of manufacturing a silica glass by a sol-gel method. The apparatus includes a sol feeder for holding a sol to be dispersed, a sol container for containing the ultrasonically dispersed sol, a medium tank having a liquid-phase ultrasonic medium, an ultrasonic vibrator for generating ultrasonic waves within the tank, and a sol pipe for providing a sol feeding path connecting the sol feeder and the sol container to each other, the sol pipe having a portion submerged under the ultrasonic medium in the medium tank. The portion of the sol pipe submerged under the ultrasonic medium has a shape bent in a zigzagged fashion.

Abstract: A silica sol-gel fabrication process is provided which allows improved control of the shrinkage that takes place during the drying of a gel body. In particular, the invention makes it possible to attain extremely low shrinkage through the completion of the drying stage, e.g., below 1% linear shrinkage, in relatively large sol-gel bodies of (dry weight) 1 kg or more, typically 10 kg or more, or even 40 kg or more, compared to the much higher shrinkages typically encountered. Specifically, use of a particular polymeric additive makes it possible for a gel body to experience linear shrinkage at least 55% less than an identical process without the polymeric additive.

Abstract: A new method is disclosed for producing thin plates by sintering a thin gel plate (e.g., silica) made using a sol-gel process, which substantially eliminates warpage of the plate during the sintering step. Sintering a sol-gel based silica plate to a dense glass typically causes significant shrinkage, and this can cause the plate to curl, especially around its edges. This phenomenon is referred to as warpage. In the method of the invention, the sintering step is performed while the gel plate is mounted on a support surface, separated by a thin layer of refractory powder. At the high sintering temperature, the powder partially fuses and sticks to both the gel plate and the support surface, which prevents non-uniform stresses in the gel plate from warping the plate.

Abstract: The invention provides a method for efficiently producing, in a low temperature region, a thin film or micro-spherules of a single component type or a multi-component type metal oxide glass, wherein an organic metal compound is subjected to hydrolyzation in a reaction liquid consisting of water and an organic solvent, with halogen ions (F−, Cl−) as a catalyst in the presence of boron ions (B′), followed by dehydration and condensation, after which a reaction product is vitrified at a temperature of 200° C. or below, thereby obtaining the single component type or multi-component type metal oxide glass film (reaction at a pH value between 5.0 and 4.5), or micro-spherules (reaction at a pH value between 8 an 10). Transparent and homogeneous glass film or micro-spherules, which are excellent in the heat-resistance, moisture-resistance, insulating property, gas-barrier property, and ion-migration preventive property, can be obtained in a normal temperature region.

Abstract: A composition for production of silica glass using a sol-gel process is described, comprising silica particles, a dispersing agent, and a solution containing a polymerizable monomer for formation of acrylic resin and a crosslink agent dissolved in distilled water. The polymerizable monomer is n-methylol acrylamide or n-methylol methacrylamide. A method for production of silica glass is described, including the step of adding silica particles and a dispersing agent to a premix solution of the polymerizable monomer for formation of acrylic resin and the crosslink agent dissolved in distilled water.

Abstract: The invention relates to a water-repellent glass pane having a glass substrate and a water-repellent film formed thereon. This glass pane is prepared by a first or second method. The first method includes sequential steps of (a) mixing together a raw material for producing the water-repellent film, an organic solvent for diluting the raw material, and water for hydrolyzing the raw material, such that the raw material is subjected to hydrolysis and then to dehydration and polycondensation, thereby to turn a mixture of the raw material, the organic solvent and the water into a sol; (b) adjusting water content of the sol, thereby to prepare a coating liquid; and (c) applying the coating liquid to the glass substrate, in an atmosphere having a first temperature and a relative humidity.

Abstract: An object of the present invention is to provide a quartz glass body, especially a quartz glass jig for plasma reaction in producing semiconductors having excellent resistance against plasma corrosion, particularly, excellent corrosion resistance against F-based gaseous plasma; and a method for producing the same. A body made of quartz glass containing a metallic element and having an improved resistance against plasma corrosion is provided that contains bubbles and crystalline phase at an amount expressed by projected area of less than 100 mm2 per 100 cm3.

Abstract: Fused silica stepper lens for photolithographic application is disclosed which is resistant to laser-induced damage, specifically, compaction or densification which can lead to an increase in the optical path length of the lens.

Abstract: This invention relates to a method of manufacturing a product based on a simple or mixed metal oxide, or silicon oxide, from a charge of one or more precursors comprising one or more organic precursors. These oxides can be, for example, oxides of Ti, Al, Mg, Th, Si, Ba, Bc or Zr etc. The method comprises bringing the charge of organo-metallic precursors into contact with a reaction medium that comprises supercritical C02, at a temperature of from 31 to 100° C. and a supercritical pressure of from 3×107 to 5×107 Pa, in order to form from the precursor, a product based on a simple or mixed metal oxide, or silicon oxide, from the reaction medium by reducing the pressure of the supercritical C02 to a pressure lower than the supercritical pressure.

Abstract: A process for producing a linearly-miniaturized, densified optical product, which entails a) cold filling a mould with a liquid colloidal dispersion formed from a chemical precursor; b) polycondensing the liquid colloidal dispersion to obtain a gel; c) supercritically drying the gel to form an amorphous aerogel having dimensions corresponding to the mould; and d) isotropically miniaturizing the amorphous monolithic aerogel obtained.

Abstract: A fabrication method of graded index silica glass is disclosed. The method according to the present invention includes the steps of dispersing to form sol by mixing a starting material with a dispersion medium; molding the sol into a moisturized gel with a predetermined shape using a molding frame and separating the moisturized gel from the molding frame; drying the moisturized gel under a predetermined temperature and humidity level to remove the dispersion medium and to form a first dry gel having a predetermined moisture content distribution, hydrolyzing the moisture remained in the first dry gel and an additive solution by putting the first dry gel into the additive solution; re-drying the first dry gel, which underwent said hydrolysis, to form a second dry gel; and, thermal processing the second dry gel by supplying reaction gas thereto, removing impurities therefrom and annealing for isolation.

Abstract: Pyrogenically prepared silicon dioxide with the following physicochemical properties:

Abstract: A sol-gel method of preparing a powder for use in forming a glass is provided, along with methods of preparing glasses and glass fibers from the powder. The inventive method allows for the incorporation of a wide range of elements and compositions into a homogeneous glass or glass fiber that is substantially free of hydroxide groups. In addition, dopants incorporated into glasses prepared by the inventive method are uniformly distributed throughout the glass structure.

Abstract: A process for producing an article having a finely uneven surface coated with a film, which has high heat resistance and which neither cracks nor peels off from a substrate, by forming a film of a sol material between a substrate and a mold in such a manner that the film is in close contact with them and applying heat to form a gelled film, which has a surface configuration that is the inversion of the surface configuration of the mold, on the surface of the substrate, wherein the sol material contains (A) R2SiX2 (R is an alkyl group and X is an alkoxyl group or halogen atom) and (B) R′SiX′3 (R′ is an aryl group or substituted aryl group and X′ is an alkoxyl group or halogen atom).

Abstract: A fabrication method of graded index silica glass is disclosed. The method according to the present invention includes the steps of dispersing to form sol by mixing a starting material with a dispersion medium; molding the sol into a moisturized gel with a predetermined shape using a molding frame and separating the moisturized gel from the molding frame; drying the moisturized gel under a predetermined temperature and humidity level to remove the dispersion medium and to form a first dry gel having a predetermined moisture content distribution, hydrolyzing the moisture remained in the first dry gel and an additive solution by putting the first dry gel into the additive solution; re-drying the first dry gel, which underwent said hydrolysis, to form a second dry gel; and, thermal processing the second dry gel by supplying reaction gas thereto, removing impurities therefrom and annealing for isolation.

Abstract: SiO2—TiO2 glasses having a low coefficient of thermal expansion are produced by a molding being produced that consists of SiO2 powder, SiO2—TiO2 powder or TiO2 powder and that contains by way of secondary component a titanium-containing component which is converted into amorphous TiO2.