Abstract: Surface-modified, pyrogenically prepared titanium dioxides coated with silicon dioxide are prepared by spraying the pyrogenically prepared titanium dioxides coated with silicon dioxide with a surface-modifying agent and then tempering them. They can be used in sun protection formulations.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 200±25 m2/g, wherein the aggregates display an average surface area of 7000 to 12000 nm2, an average equivalent circle diameter (ECD) of 80 to 100 nm and an average circumference of 850 to 1050 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1570 to 1630° C. is obtained. It can be used as a filler.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 90±15 m2/g, wherein the aggregates display an average surface area of 10000 to 20000 nm2, an average equivalent circle diameter (ECD) of 90 to 130 nm and an average circumference of 1000 to 1400 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1810 to 1890° C. is obtained. Dispersion containing the pyrogenically produced silicon dioxide powder.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 150±15 m2/g, wherein the aggregates display an average surface area of 12000 to 20000 nm2, an average equivalent circle diameter (ECD) of 90 to 120 nm and an average circumference of 1150 to 1700 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1670 to 1730° C. is obtained. Silicone sealing compound containing the pyrogenically produced silicon dioxide powder.

Abstract: Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 300±25 m2/g, wherein the aggregates display an average surface area of 4800 to 6000 nm2, an average equivalent circle diameter (ECD) of 60 to 80 nm and an average circumference of 580 to 750 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a maximum of up to 40 wt. % of a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1390 to 1450° C. is obtained. It can be used as a filler.

Abstract: Pyrogenically prepared surface-modified silicon dioxide-titanium dioxide mixed oxides are prepared by spraying pyrogenically prepared silicon dioxide-titanium dioxide mixed oxides with a surface-modifying agent.

Abstract: Stable, aqueous dispersion containing silicon dioxide powder having a hydroxyl group density of 2.5 to 4.7 OH/nm2, which is obtained from a silicon dioxide powder produced by a flame hydrolysis process under acid conditions. The dispersion is produced by incorporating the silicon dioxide powder into an aqueous solution by means of a dispersing device. The dispersion can be used to produce glass articles.

Abstract: Pyrogenically produced silica powder with a BET surface of 30: to 90 m2/g, a dibutyl phthalate number of at least 80 and a tamped density of no more than 110 g/l. It is produced in that at least one vaporous silicon compound, a gas containing free oxygen and a combustible gas are mixed together in a closed burner and then burnt in a flame in the flame tube of the burner, the solid obtained is separated from the gas mixture and optionally purified, wherein the oxygen content of the gas containing free oxygen is adjusted such that die lambda value is greater than or equal to 1, and die gamma value is between 1.2 and 1.8. It can be used in toner applications.

Abstract: Powder consisting of particles with a core of titanium dioxide and a coating of silicon dioxide, which powder has a content of silicon dioxide of between 0.5 and 40 wt. %, a BET surface of between 5 and 300 m2/g, and which consists of primary particles that have a coating of silicon dioxide and a core of titanium dioxide. The powder is produced according to a process in which a vaporisable silicon compound and a vaporisable titanium compound are mixed corresponding to the subsequently desired ratio of SiO2 and TiO2 in the product, are vaporised at temperatures of 200° C.

Abstract: A powder mixture consisting of zinc/titanium mixed oxide particles, titanium dioxide particles and zinc oxide particles, in which the zinc/titanium mixed oxide particles have a composition according to the formula (ZnO)1-x(TiO2)x, where 0.01<x<0.99, and are obtained from a thermal process and the powder mixture exhibits remission which, in the UV range from 320 to 400 nm, is lower than that of titanium dioxide and, in the UV range below 320 nm, is lower than that of zinc oxide. The powder mixture may be used in sunscreen preparations.

Abstract: A silicon-titanium mixed oxide powder contains aggregates of primary particles selected from amorphous silicon dioxide particles, crystalline titanium dioxide particles, and silicon-titanium mixed oxide particles each having an amorphous silicon dioxide fraction and a crystalline titanium dioxide fraction. The silicon-titanium mixed oxide particles predominate in the powder. The powder exhibits a BET surface area of from 20 to 200 m2/g, and a titanium dioxide content in a range of from greater than 10 wt. % to less than 70 wt. %. An X-ray diffractogram of the powder exhibits the diffraction patterns of rutile and anatase, with a rutile/anatase ratio of from 2:98 to 98:2. The powder can be produced by vaporizing a silicon halide and a titanium halide at temperatures of less than 180° C.

Abstract: Carbon black with an OAN, measured on the beaded carbon black, of less than 120 ml/100 g. A process for the preparation of the carbon black is described, wherein a salt solution is converted into an aerosol and this is then introduced into the carbon black formation zone. The carbon black can be used in inks, paints, lacquers, printing inks and ink-jet inks, and for coloring plastics.

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: 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: 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: 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: 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: 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.