Abstract: Dispersion comprising hydrophobic pyrogenically prepared silicon dioxide, alcohol and at least one additive which promotes the dispersion and, as additional component, at least one insecticide and/or acaricide. The dispersion can be canned in spray cans and used as insecticide.

Abstract: A dispersion containing aluminum oxide of pyrogenic origin and water, where the aluminum oxide is present in the form of aggregated primary particles with a BET surface area of 20 to 200 m2/g and has a mean, volume-based aggregate diameter in the dispersion of less than 100 nm, and is surface-modified with (i) organophosphonic acids, or salts thereof, and (ii) at least one hydroxycarboxylic acids or salts thereof.

Abstract: Process for preparing an alkaline dispersion of aggregated silicon dioxide particles by dividing a preliminary dispersion within a pH of 3 to 5 into at least two streams, placing these streams under a pressure of at least 50 bar and depressurizing them to a collision point, each via one nozzle, in a grinding chamber, and admixing the dispersion that runs off at the bottom, while still in the grinding chamber, with an alkaline substance in an amount such that the dispersion overall has a pH of more than 7.

Abstract: Dispersion of aluminium oxide, characterised in that it contains 20 to 60 wt.-% of pyrogenically-produced aluminium oxide powder in form of aggregates of primary particles, wherein the powder has - a BET specific surface area of from 50 to 150 m2/g—a ratio Sears number/BET surface area which is from about 0.150 to 0.160, wherein the mean aggregate diameter in the dispersion is less than 200 nm.

Abstract: An aqueous dispersion that can be used in the coating of glass, ceramics and metal surfaces is prepared by placing, in water, an aggregated titanium dioxide powder having a specific surface area of from 20 to 150 m2/g in such an amount that the desired dispersion contains at least 20 wt. % titanium dioxide, and at least one amino alcohol having from 1 to 6 carbon atoms, and at least one carboxylic acid selected from dibasic carboxylic acids and/or hydroxycarboxylic acids having from 2 to 6 carbon atoms. A pre-dispersion is produced by introducing energy in an amount of less than 200 kJ/m3. Then a dispersion is produced in which the aggregated titanium dioxide powder has a mean, volume-related aggregate diameter of less than 150 nm by grinding the pre-dispersion with a high-energy mill at a pressure of at least 500 bar.

Abstract: Dispersion containing, in addition to water, 0.5 to 20% by weight of hydrophobic silica, 0.01 to 10% by weight of a gelling additive, or viscosity-increasing additive which, as further components, contains at least one phenol or at least one phenol derivative and/or at least one aldehyde. It is prepared by dispersing the individual components successively or together in water, in which case the individual components are deaerated before and/or during the addition or the dispersion is deaerated during the individual dispersion steps and thereafter the residual air present in the dispersion is removed by application of vacuum. The dispersion can be used as insecticide and for controlling pathogenic agents.

Abstract: A method of fractionating a dispersion of oxidic nanoparticles wherein at least one step of the method is a membrane crossflow filtration step, the flow of the dispersion over the membrane being brought about by means of driven rotating parts; and dispersions of oxidic nanoparticles that are obtainable by the method.

Abstract: An aqueous dispersion for use as a finishing agent for textiles, wherein the dispersion contains a pyrogenically produced, aggregated silicon dioxide powder and a cationic polymer which is soluble in the dispersion, wherein the cationic polymer is present in a quantity such that the particles of the silicon dioxide powder exhibit a positive zeta potential.

Abstract: Dispersion comprising water and mixed potassium silicon oxide powder, where—the mixed oxide powder is in the form of aggregates of primary particles, has a BET surface area of 100 to 400 m2/g, has an average aggregate diameter in the dispersion of less than 100 nm, and possesses a potassium fraction of 0.05% to 1.5% by weight, calculated as K2O and based on the mixed oxide powder, and—the dispersion has a fraction of mixed oxide powder in the dispersion of 25% to 40% by weight, the sum of water and mixed oxide powder is at least 98% by weight and the pH is 9 to 11.5.

Abstract: Preparation for producing refractory materials, characterized in that it comprises one or more particulate, refractory components and one or more binders, where—the particulate, refractory component has a mean particle diameter of >0.3 m and—the binder is selected from among—from 0.05 to 50% by weight of a very finely particulate binder having a mean particle diameter of from 10 nm to 0.3 m selected from the group consisting of aluminium oxide, titanium dioxide, zirconium dioxide and/or mixed oxides of the abovementioned oxides, —from 0 to 20% by weight of an inorganic binder, from 0 to 20% by weight of a hydraulically setting binder, —from 0 to 15% by weight of an organic, silicon-free binder—and the preparation additionally contains from 0 to 35% by weight of water, where—the proportion of the particulate, refractory component is equal to 100 and the percentages of the further materials in the preparation are based on the particulate component.

Abstract: Aqueous dispersion which comprises hydrophobized silicon dioxide powder with a content of between 5 and 50 wt. % and which comprises at least one compound of the general formula R & supl; —COO—(CH2-CH(Ph)—O)a-(CnH2n-xR2x-O)b-R3 (I). It is prepared by dispersing the hydrophobic silicon dioxide powder, dispersing agent and optionally pH-regulating substances and further additives in an aqueous medium. It can be employed as an additive to waterborne fillers in the automobile industry, as a coating constituent in can and coil coating processes, as an additive in water-based UV-curable formulations e.g. for wood preservation and as a constituent of protective lacquer films.

Abstract: Aqueous dispersion containing transition aluminium oxide as only solid and a dispersant, in which—the transition aluminium oxide is present in the form of aggregates of primary particles, the content of transition aluminium oxide in the dispersion is from 40 to 65% by weight, the aggregates in the dispersion have a mean aggregate diameter of less than 100 nm,—the dispersant contains polyaluminium hydroxychloride, polyaluminium hydroxynitrate and/or polyaluminium hydroxysulphate, the dispersion has a pH of from 3 to 5.

Abstract: A process for the preparation of products of high early strength comprising hydraulic binders, in which a hydraulic binder, water and 0.1 to 5% by weight, based on the hydraulic binder, of a finely divided titanium dioxide are mixed with agitation and in any desired sequence.

Abstract: Stable, pourable silicon dioxide dispersion, in which the average, number-related aggregate diameter of the silicon dioxide particles in dispersion is less than 200 nm, and which comprises at least 35 wt. % of a silicon dioxide powder, 3 to 35 wt. % of at least one polyol, 20 to 60 wt. % of water, 0 to 10 wt. % of an additive and a substance having an alkaline action in an amount such that a pH of 10<pH<12 is established. It can be prepared by a procedure in which silicon dioxide powder is introduced into water and a polyol in a rotor/stator machine, the pH being less than 5, and the mixture is dispersed until the current uptake of the rotor/stator machine is largely constant, and a substance having an alkaline action is subsequently added in an amount such that a pH of the dispersion of 10<pH<12 results, the substance having an alkaline reaction being added so rapidly that no gel formation takes place.

Abstract: Dispersion containing pyrogenic silicon-titanium mixed oxide powders with a silicon dioxide content of 75 to 99.99 wt.-% and a titanium dioxide content of 0.01 to 25 wt. %, water and a basic, quaternary ammonium compound, wherein the mean aggregate diameter of the particles of the silicon-titanium mixed oxide powder in the dispersion is 200 nm at most. Process for the production of a titanium-containing zeolite with the use of the dispersion.

Abstract: A method of fractionating a dispersion of oxidic nanoparticles wherein at least one step of the method is a membrane crossflow filtration step, the flow of the dispersion over the membrane being brought about by means of driven rotating parts; and dispersions of oxidic nanoparticles that are obtainable by the method.

Abstract: A method and device for producing a finely divided dispersion of solids having a mean particle size of 10 nm to 10 µm, in which at least two flows of a predispersion are sprayed by means of pumps, preferably high-pressure pumps, through one nozzle each into a grinding chamber enclosed by a reactor housing onto a collision point, wherein the grinding chamber is flooded with the predispersion and the finally divided dispersion is removed from the grinding chamber by the overpressure of the predispersion continuing to flow into the grinding chamber.

Abstract: Dispersion containing aluminium oxide and water, wherein the aluminium oxide is present in the form of aggregated primary particles with a BET surface area of 20 to 200 m2/g and has a mean, volume-based aggregate diameter in the dispersion of less than 100 nm, is modified with organophosphonic acids and/or salts thereof, wherein the surface is completely or partially modified, the organophosphonic acids bear at least one amino and/or hydroxy group and is present in a content of 20 to 70 wt. %, based on the total quantity of the dispersion. Preparation containing this dispersion and a melamine resin. Cured product obtainable from the preparation. Use of the dispersion, of the preparation or of the cured product for the preparation of laminates.

Abstract: Dispersion of zirconium dioxide having a solids content of from 30 to 75 wt. %, based on the total amount of the dispersion, and a median value of the particle size distribution in the dispersion of less than 200 nm, obtainable by predispersing a zirconium dioxide powder and/or a zirconium mixed oxide powder having a ZrC>2 content of at least 70 wt. %, the powders being in the form of aggregated primary particles and having no internal surface and a BET surface area of the powder of 60±15 m2/g, in a dispersing agent in the presence of from 0.1 to 5 wt.

Abstract: Preparation containing at least one photocatalytically active metal oxide powder with a specific surface area of at least 20 m2/g at least one wetting agent. Use of the preparation for weed control.