Abstract: Aqueous dispersion comprising silicon/titanium mixed oxide powder with a BET surface area of 5 to 500 m2/g which has been prepared by flame hydrolysis and has a titanium dioxide content of 0.5 to 20 wt. %, based on the powder, water and at least one pH-regulating substance which can be removed completely from the reaction mixture on heating, the aqueous dispersion having a solids content of between 40 and 80 wt. %. A green body produced therefrom with a green density of between 40 and 85%. A shaped glass article of optical quality with a coefficient of thermal expansion of not more than 0.5×10−6/K produced from the green body.

Abstract: The present invention relates to an aqueous dispersion containing a silicon dioxide powder coated with cerium oxide. In addition, the present invention provides a method of producing an aqueous dispersion containing a silicon dioxide powder coated with cerium oxide and methods of using this aqueous dispersion for chemical-mechanical polishing.

Abstract: Pyrogenically produced silicon dioxide doped with aluminum oxide by means of an aerosol is produced by introducing an aqueous aerosol of an aluminum salt into the flame of a pyrogenic silica producing flame hydrolysis method or a flame oxidation method. The silicon dioxide doped with Al2O3 by means of an aerosol may inter alia be used in the production of inkjet paper or inkjet films.

Abstract: A process for the preparation of doped, pyrogenically prepared titanium dioxide is described. The titanium dioxide is doped with zinc oxide, platinum oxide, magnesium oxide, or aluminium oxide, by injecting an aerosol of the oxide into the production stream. The doped titanium dioxide may be used as a photocatalyst or UV absorber.

Abstract: Doped, pyrogenically prepared oxides of metals and/or non-metals which are doped with one or more doping components in an amount of 0.00001 to 20 wt. %. The doping component may be a metal and/or non-metal or an oxide and/or a salt of a metal and/or a non-metal. The BET surface area of the doped oxide may be between 5 and 600 m2/g. The doped pyrogenically prepared oxides of metals and/or non-metals are prepared by adding an aerosol which contains an aqueous solution of a metal and/or non-metal to the gas mixture during the flame hydrolysis of vaporizable compounds of metals and/or non-metals.

Abstract: A layer which is obtained by thermal treatment from an aqueous dispersion applied to a substrate, the dispersion containing silicon/titanium mixed oxide powder prepared by flame hydrolysis. It is prepared by applying a dispersion which contains the silicon/titanium mixed oxide powder to a substrate and then sintering by using a thermal treatment. It can be used, for example, on materials with very low coefficients of expansion.

Abstract: An ink jet recording material excellent in all characteristics including drying property, ink absorbency, water resistance and the like, is provided. The ink jet recording material has an ink-receiving layer comprising hydrophilic resin and inorganic pigment, the ink-receiving layer containing silica particles surface-doped with alumina as the inorganic pigment. The alumina-doped silica is prepared by a process employing flame hydrolysis techniques combined with pyrolysis. The ink-receiving layer preferably contains the alumina-doped silica in an amount ranging from 5 to 200 weight parts based on 100 weight parts of the hydrophilic resin.

Abstract: Dispersions of pyrogenic oxides, doped using an aerosol, are prepared by mixing the oxide with a suspending agent and milling. The dispersions can be used to prepare inkjet paper.

Abstract: Metal oxide particles having a metal oxide core and a silicon dioxide coating have a low structure. The particle are produced by a base dissolved in water being added under agitation to a dispersion comprising a metal oxide, at least one compound of the type XnSi(OR)4−n, and water, the reaction product being separated out, optionally washed with water and dried. The metal oxide particles coated with silicon dioxide may be used in sun screening agents and in chemical-mechanical-polishing (CMP) applications.

Abstract: Pyrogenically produced aluminum-silicon mixed oxides with a BET surface of more than 300 m2/g and a composition of 0.01 to 99.99% by wt. Al2O3, remainder SiO2 are produced in accordance with the method of flame pyrolysis or preferably flame hydrolysis by a joint combustion of the gaseous raw substances. They can be used to produce coating colors, especially for inkjet papers or inkjet foils or other inkjet materials.

Abstract: Granules based on pyrogenically prepared silicon dioxide doped with aluminum oxide by means of an aerosol, which granules have the characteristic data: 1 mean particle diameter: from 10 to 150 &mgr;m BET surface area: from 25 to 100 m2/g pH value: from 3 to 6 tamped density: from 400 to 1200 g/l

Abstract: Pyrogenically, especially flame-hydrolytically produced zirconium dioxide powder with a specific surface area between 20 and 200 m2/g, a primary particle size between 7 and 100 nm, a tamped density of the deacidified and non-deacidified zirconium dioxide between 40 and 150 g/l with Sears numbers of the deacidified and non-deacidified zirconium dioxide between 1 and 20 ml/2 g and with a chlorine content of the deacidified zirconium dioxide less than 0.6% by weight. These are produced by evaporating zirconium halides, mixing the vapors alone or together with a carrier gas in a burner with air, oxygen, nitrogen and hydrogen, causing the gases to react with each other in a flame in a closed burner chamber, cooling off the waste gases and the zirconium dioxide in a heat exchanger unit, separating the waste gases from the zirconium dioxide and removing any halide remnants adhering to the zirconium dioxide by a heat treatment with moistened air.

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: Oxide particles with a doping component distributed in the core and a shell surrounding the core, which can be prepared by first introducing the doping into the core of a metal oxide or metalloid oxide via an aerosol in a pyrogenic process, subsequently coating the doped core with a salt solution of a metal or metalloid, drying it and optionally calcining it; which particles can be employed for chemical-mechanical polishing.

Abstract: A method for producing potassium-doped pyrogenic oxides involves mixing a gaseous mixture including a pyrogenic oxide precursor and an aqueous aerosol containing a potassium salt to form an aerosol-gaseous mixture which is then reacted in a flame under conditions suitable for producing pyrogenic oxides by flame oxidation or flame hydrolysis to form the potassium-doped pyrogenic oxides product. The particle product is spherical, has a BET surface between 1 and 1000 m2/g and a narrow distribution of particle size of at least 0.7. The doped oxides can be used as polishing material (CMP application).

Abstract: Surface-modified, doped, pyrogenically produced oxides surface-modified with one or several compounds from the following groups:

Abstract: An ink jet recording material excellent in all characteristics including drying property, ink absorbency, water resistance and the like, is provided. The ink jet recording material has an ink-receiving layer comprising hydrophilic resin and inorganic pigment, the ink-receiving layer containing silica particles surface-doped with alumina as the inorganic pigment. The alumina-doped silica is prepared by a process employing flame hydrolysis techniques combined with pyrolysis. The ink-receiving layer preferably contains the alumina-doped silica in an amount ranging from 5 to 200 weight parts based on 100 weight parts of the hydrophilic resin.

Abstract: A pyrogenic process is used to prepare alkali-doped silica particles. Particles produced by this process exhibit homogeneous doping, reduced agglomeration, greater stability and higher removal rates. Aqueous dispersions containing alkali-doped pyrogenic silica with average particle size less than 100 nm are used for polishing surfaces (CMP).

Abstract: A silicon-aluminum mixed oxide produced by flame hydrolysis and having a composition of from 1 to 99.999 wt. % Al2O3, the remainder being SiO2, which mixed oxide exhibits an amorphous structure in the X-ray diffraction pattern and consists of intergrown primary particles, and in these primary particles crystallites are present. These crystallites having sizes of between one and 200 namometers and the specific surface of the powder being between 5 and 300 m2/g. These products are produced by a process wherein silicon halide and aluminum halide are vaporized in a particular ratio to one another and are homogeneously mixed with air, oxygen and hydrogen in a mixing unit by means of any carrier gas, this mixture undergoes combustion in a burner of known construction and, after the separation of the solids from the vapour phase, any traces of halide possibly adhering to the product are separated off in a further processing step by means of moist air at elevated temperature.

Abstract: Aqueous dispersion containing a silicon-aluminum mixed oxide powder, the powder containing 0.1 to 99.9 wt. % Al2O3 and Si—O—Al-bonds. The dispersion can be produced using dispersing and/or grinding devices which a achieve an energy input of at least 200 KJ/m3. The dispersion can be used for the chemical-mechanical polishing of semiconductor substrates.