Abstract: The present invention provides methods of producing substantially anatase-free titanium dioxide by mixing titanium tetrachloride with a silicon compound to form an admixture, and introducing the admixture and oxygen into a reaction zone to produce the substantially anatase-free titanium dioxide. The reaction zone has a pressure of greater than 55 psig.

Abstract: Methods of forming metal alkoxides and methods of forming precursor solutions of metal alkoxides suitable for the coating of glass in the manufacture of electrochromic devices are disclosed. The method of forming metal alkoxides involves dissolving the metal halide in an anhydrous solvent and reacting it with an alcohol and (together with the addition of the alcohol or subsequently) adding an epoxide, and then evaporating-off the volatile components of the reaction product to leave a solid metal alkoxide that is substantially free of halide. The alkoxide may then be dissolved in a solvent including an alcohol (preferably ethanol) containing a small proportion of water to produce a precursor solution suitable for coating glass, the coating then being hydrolyzed to form a sol-gel and then baked to remove volatile components and to yield a thin layer of metal oxide.

Abstract: A method for producing fine particles of metal oxide characterized in that metal halide is hydrolyzed in the presence of organic solvent. According to this invention, under hydrolysis of titanium tetrachrolide, anatase type titanium oxide can be obtained by selecting hydrophilic organic solvent, and rutile type titanium oxide can be obtained by selecting hydrophobic organic solvent.

Abstract: A barium titanate powder has an average particle size ranging from 0.1-1.0 &mgr;m, a CV value (standard deviation of the particle size/the average particle size) of the particle size distribution being 40% or less, and a zeta-potential ranging from −30 to −60 mV measured by a laser Doppler method using electrophoresis at pH 6.4. The barium titanate powder is presintered at a temperature ranging from 900 to 1200° C. The barium titanate powder has superior dispersion characteristics in slurrying, and is capable of partly inhibiting agglomeration of the barium titanate after sintering. It is therefore suitable as materials for dielectric layers of multilayer ceramic capacitors. In particular, the barium titanate has a sintered density of 95% or more of the theoretical density thereof, and the dielectric constant is 4000 or more.

Abstract: A novel process for the preparation of ultra-fine powders of metal oxide wherein a surfactant is added to the solution for the preparation of the metal oxide to provide nanometer metal oxide powders without the utilization of vacuum or high pressure conditions is disclosed.

Abstract: Dendrite or asteroidal titanium dioxide micro-particles having a length of 0.2 to 0.5 .mu.m, a thickness of 0.05 to 0.1 .mu.m, and a specific surface area of 20 to 130 m.sup.2 /gram, are produced by treating hydrated titanium oxide particles with an alkali, mixing instantaneously the resulting reaction product with an amount of hydrochloric acid in a ratio of 1 to 4 mols of hydrochloric acid to one mol of the titanium oxide in the reaction product to effect a reaction, then aging under heat at 85.degree. C. or higher, and then drying or, if necessary, firing after the drying, and subsequently may be coated with at least one from oxides and hydrated oxides of elements selected from aluminum, silicon, titanium, zirconium, tin and antimony to improve the dispersibility and resistance to light of the particles, or may be coated with tin oxide containing antimony or indium oxide containing tin to make the particles electroconductive.

Abstract: A titanyl sulfate solution or a titanium tetrachloride solution is neutralized with an alkali to form orthotitanic acid, to which hydrochloric acid is added such as to adjust the TiO.sub.2 concentration to 80-140 g/L and the HCl concentration to 90-150 g/L and a synthesis reaction is performed at a temperature of 25-60.degree. C. to produce titanium oxide particles in which needles aggregate and/or bind together to yield fan-shaped particles.

Abstract: A method for production of mono-dispersed and crystalline titanium dioxide ultra fine powders comprises preparing an aqueous titanyl chloride solution, diluting the aqueous titanyl chloride solution to a concentration of between about 0.2 to 1.2 mole and heating the diluted aqueous titanyl chloride solution and maintaining the solution in a temperature range of between 15 to 155.degree. C. to precipitate titanium dioxide. The aqueous titanyl chloride solution is prepared by adding ice pieces of distilled water or icing distilled water to undiluted titanium tetrachloride.

Abstract: The present invention provides a process for producing titanium dioxide (TiO.sub.2) pigment having a coating comprising silica and a second oxide selected from the group consisting of oxides of boron, phosphorus, magnesium, niobium, germanium, and mixtures thereof, comprising the steps of (a) reacting titanium tetrachloride (TiCl.sub.4) in the vapor phase with an aluminum compound and an oxygen-containing gas in a reactor at a temperature in the range of about 900.degree. C. to about 1600.degree. C. to provide a gaseous suspension comprising TiO.sub.2 particles, (b) contacting the gaseous suspension comprising the TiO.sub.2 particles with a silicon halide and an oxide precursor of boron, phosphorus, magnesium, niobium, germanium, and mixtures thereof, and (c) cooling the gaseous suspension to produce TiO.sub.2 pigment having a coating comprising silica and a second oxide.

Abstract: The process for preparing crystalline titania powders is provided. The process comprises dissolving titanium salt in a mixed solvent of water and alcohol, heating the resulting solution to 15.degree..about.75.degree. C. to form titanium hydroxide precipitates, and crystallizing the titanium hydroxide precipitates.

Abstract: The present invention are methods for preparing hydrous titanium oxide spherules, hydrous titanium oxide gels such as gel slabs, films, capillary and electrophoresis gels, titanium monohydrogen phosphate spherules, hydrous titanium oxide spherules having suspendible particles homogeneously embedded within to form a composite sorbent, titanium monohydrogen phosphate spherules having suspendible particles of at least one different sorbent homogeneously embedded within to form a composite sorbent having a desired crystallinity, titanium oxide spherules in the form of anatase, brookite or rutile, titanium oxide spherules having suspendible particles homogeneously embedded within to form a composite, hydrous titanium oxide fiber materials, titanium oxide fiber materials, hydrous titanium oxide fiber materials having suspendible particles homogeneously embedded within to form a composite, titanium oxide fiber materials having suspendible particles homogeneously embedded within to form a composite and spherules of b

Abstract: An ultrafine titanium dioxide powder is disclosed that can be produced by hydrothermal treating an amino titanium oxalate composition. Ultrafine titanium dioxide powders are useful in cosmetic and other applications for controlling exposure to ultraviolet (UV) light.

Abstract: The present invention provides a photochromic compound oxide of Ti, Fe and Si which may contain Al and a cosmetic comprising the above photochromic compound oxide which, even when a light quantity change instantaneously occurs as in taking a photographic picture with the use of flashlight, exhibits satisfactory changes in lightness and color difference in accordance with the above instantaneous light quantity change.

Abstract: The present invention relates to neutral titanium dioxide sols which have been stabilized with hydroxycarboxylic acids or derivatives thereof and are treated with metal ions, inorganic anions, complexing agents and/or oxidizing agents to improve the photostability.

Abstract: The present invention provides a method for producing ceramic fine particles comprising the steps of supplying gaseous starting materials or starting material droplets to a reaction space arranged in an annular portion between inner and outer cylinders of a coaxial, double-cylinder reaction apparatus, the reaction apparatus having a stationary outer cylinder and a rotatable inner cylinder; and subjecting the gaseous starting materials or the starting material droplets to reaction in the reaction space while rotating the inner cylinder. Also, the present invention provides a production apparatus used therefor.

Abstract: A process for producing substantially anatase-free TiO.sub.2 by addition of a silicon halide in a reaction of TiCl.sub.4 and an oxygen-containing gas in a plug flow reactor is disclosed. Pigmentary properties such as gloss and CBU are enhanced without loss of durability.

Abstract: A process for the preparation of very pure titanium dioxide by reacting titanium tetrahalides with sulphuric acid, hydrolysis the titanyl sulphate solution obtained and calcining the hydrolysate is disclosed wherein the reaction between titanium tetrahalide and aqueous 20-40% by weight strength sulphuric acid is performed in such a way that crystallisation of titanyl sulphate does not take place, the hydrogen halide is separated, the solution is optionally concentrated and filtered and then the ratio by weight of sulphuric acid to titanium dioxide is adjusted to between 1.7 and 2.0 and the titanium dioxide concentration is adjusted to between 250 and 300 g/l, the solution is hydrolyzed and the resulting titanium oxide hydrate is filtered off and calcined to give Futile or anatase.

Abstract: A novel process for preparing titanium dioxide from a titanium chloride consists of heating an aqueous solution of the titanium chloride in the presence of a salt of a polycarboxylic acid. The process is useful for producing titanium dioxide having a particle size between 0.1 and 1 micrometer and a purity which is suitable for more demanding electroceramic applications.

Abstract: A titanium oxide sol comprising a disperse medium and generally rectangular, non-spherical particles of titanium oxide dispersed in the disperse medium, with narrow scatteres in particle size and configuration. The sol is excellent in dispersibility, long-term stability and light-resistance and, is stable in a wide pH range without causing agglomeration. Moreover, it is excellent in absorbance of ultraviolet ray and in transmittance of visible light. The sol may be prepared by a process wherein hydrogen peroxide is added to a gel or sol of hydrated titanium oxide to dissolve the hydrated titanium oxide in said gel or sol, and the resulting aqueous titanic acid solution is heated in the presence of at least one compound selected from inorganic compounds of metals belonging the Group II, III, IV, V, VI and VIII of the periodic table.

Abstract: An improved process is provided for producing titanium tetrachloride vapor admixed with a desired particular amount of aluminum trichloride vapor for use in the production of rutile titanium dioxide. The vapor mixture is derived from a titanium tetrachloride solution containing the desired particular amount of aluminum trichloride. The solution is produced continuously by dissolving aluminum trichloride in a heated stream of liquid titanium tetrachloride utilizing a cyclic aluminum trichloride bed switching and recharging process.

Abstract: Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions.

Abstract: The present invention provides novel titanium dioxide aggregates especially suitable for an electrophotographic photosensitive material. This titanium dioxide aggregates comprise sintered aggregates of fine primary particles and have a rutile type crystal structure and an oil absorption of 35-65. This titanium dioxide aggregates which are treated with a mineral acid is also provided. There is also provided an electrophotograpic photosensitive material which contains such titanium dioxide in a photosensitive layer.

Abstract: There is provided a method of producing titanium oxides which comprises: admixing an aqueous solution of titanium tetrachloride with sulfuric acid in a molar ratio of sulfuric acid to titanium tetrachloride of at least 0.5 adding an alklai to the resultant solution to produce titanium hydroxide; and drying and calcining the titanium hydroxide. A further method is provided which comprises: adding a solution of an alkali to an aqueous solution of titanium tetrachloride having a concentration of not more than 2.5 moles/l at temperatures of not less than 50.degree. C., thereby to substantially thermally hydrolyze the titanium tetrachloride and to produce titanium hydroxide; and drying and calcining the titanium hydroxide.

Abstract: Sulfur-free anatase titanium dioxide, readily dispersible in aqueous media and well adopted for the production of electronic-grade alkaline earth metal titanates, e.g., barium and strontium titanates, is prepared by hydrolyzing a sulfur-free compound of titanium in the presence of (i) at least one acid containing either one carboxyl group and at least two hydroxyl and/or amino groups, or at least two carboxyl groups and at least one hydroxyl and/or amino group, or (ii) at least one salt of the at least one acid (i).

Abstract: A process for the production of a suspension of nuclei has been developed in which an aqueous mixture of titanium tetrachloride, aluminium ions and hydroxyl ions is cured at at temperature of from 50.degree. to the boiling point. The pH of the suspension before or after curing has a value of from 6.5 to 10.5. The aqueous mixture is prepared by mixing a solution of titanium tetrachloride with a solution of a base, e.g. sodium hydroxide and aluminium hydroxide.When used to nucleate hydrolysis in the "sulphate" process a large crystal size anatase pigment is produced.

Abstract: A process for preparing finely-divided oxides of metals of metalloids of the elements of main groups III and IV and sub-groups III, IV, V and VI of the Periodic System of Elements, comprising reacting compounds of these elements with a polymerizable hydrocarbon compound or mixture to form a polymer product, which is then thermally treated to yield the oxide product.

Abstract: A novel process is described for the preparation of monodisperse ceramic ders wherein particulate oxides or hydroxides are obtained by reaction of hydrolysable compounds with water. The reaction is carried out in the presence of a complexing agent and, optionally, a stabilizer.

Abstract: Poorly crystallized or amorphous TiO.sub.2 particulates having a mean particle size greater than 20 nm are prepared by thermally hydrolyzing a titanium compound in solution, in the presence of at least one carboxylic acid containing a hydroxyl and/or amino group, or an organophosphoric acid; the TiO.sub.2 particulates thus produced are readily molded/extruded into useful shaped articles, e.g., catalysts or catalyst supports, having good porosity and mechanical properties.

Abstract: The invention relates to a method for the preparation of particulate pigmentary titanium dioxide. The method comprises reacting, in solution, a precursor titanium tetrahalide with sulfuric acid to produce an intermediate titanyl sulfate product. Following crystallization and recovery of this intermediate product from solution the crystallized intermediate is redissolved in an aqueous solvent medium and hydrolyzed at elevated temperatures to provide a particulate amorphous titanium dioxide intermediate product. After separation from the aqueous solvent medium, this intermediate product then is subjected to calcination at elevated temperatures to produce the desired particulate titanium dioxide end product.

Abstract: The present invention is directed to a process for preparing free flowing powders of nonpigmentary titanium dioxide granular aggregates. The process comprises the providing of dried preforms of flocculated pigmentary titanium dioxide and the comminution thereof to powders of granular aggregates of enhanced bulk density and predetermined particle size.

Abstract: There is provided a method of producing titanium-oxides which comprises: admixing an aqueous solution of titanium tetrachloride with sulfuric acid in amounts of at least 0.5 times is moles as the titanium tetrachloride; adding an alkali to the resultant solution to produce titanium hydroxide; and drying and calcining the titanium hydroxide. A further method is provided which comprises: adding a solution of an alkali to an aqueous solution of titanium tetrachloride having a concentration of not more than 2.5 moles/l at temperatures of not less than 50.degree. C., thereby to substantially thermally hydrolyze the titanium tetrachloride and to produce titanium hydroxide; and drying and calcining the titanium hydroxide.

Abstract: A precursor of zirconium dioxide in form of submicronic particles is obtained by:dispersing zirconium tetrachloride in an inert, liquid organic vehicle, with a surfactant being used in order to obtain a stable dispersion,adding water to said stable dispersion in order to form an emulsion, or adding water and a co-emulsifier in order to obtain a microemulsion, so as to hydrolyse zirconium tetrachloride and cause the zirconium dioxide precursor to precipitate from the system obtained, andrecovering said precipitated precursor.Such a precursor can be submitted to treatments of calcination in order to prepare zirconium dioxide for ceramic uses.

Abstract: High purity titanium dioxide having uniform controlled particle size and method therefor. Titanium tetrachloride is mixed with water to form titanium oxychloride, which in turn is precipitated from aqueous solution to form titanium dioxide.

Abstract: The present invention includes metal oxide foam particles and a method of making the same. A decomposable metal salt feed solution is injected into a hot atomizing gas. The mixture of hot atomizing gas and feed solution is maintained in the reactor until the feed solution converts to metal oxide foam particles. The metal oxide foam particles have a high specific surface area.

Abstract: A method for producing titanium dioxide with an anatase crystal structure from a titanium oxychloride solution. Titanium tetrachloride is mixed with water to form titanium oxychloride, which in turn is mixed with an organic reagent, preferably sorbitol. The resulting solution is hydrolyzed, precipitated and calcined to form titanium dioxide with an anatase crystal structure.

Abstract: Ultra-fine spherical particles of a metal oxide having an average particle diameter of 40 nm or smaller can be prepared by a method in which a vaporizable metal compound is vaporized and decomposed under heating to give ultra-fine particles of a metal oxide followed by immediate cooling down to a temperature at which coalescence of the fine particles are prevented from coalescence. The fine particles have characteristics such as an excellent power of ultraviolet scattering.

Abstract: A method for controlling the water present in hydrogen fluoride is described which effectively removes all the water contained in the hydrogen fluoride solution to form other compounds that either have extremely low vapor pressure or are acceptable in a process such as chemical vapor purification. The method involves as one of the steps the contacting of a reactive metal halide with a hydrogen fluoride containing water. The metal halide reacts with the water contained in the hydrogen fluoride solution yielding a metal oxide, hydrogen halide, and anhydrous hydrogen fluoride. The metal oxide is a solid, with low vapor pressure, thereby effectively removing oxygen-bearing species from the hydrogen fluoride.

Abstract: A process for preparing titanium dioxide in the form of spherical particles having the particle size distribution indicated by dw/dn.ltoreq.2, by hydrolysis of strongly acid solutions of Ti(IV), wherein the molar ratio SO.sub.4.sup.= /Ti(IV) is at least 1.5, and in the presence of cationic polyelectrolytes having a molecular weight higher than 1 million and a ionicity of at least 3 milliequivalents per gram.

Abstract: A method of purificating titanium tetrachloride, comprising: heating a loose mass of catalytic metal to a temperature over 300.degree. C. approximately, introducing vapor of a crude titanium tetrachloride to contact with said metal, said chloride comprising a minor amount of metal oxychloride, causing a reaction to convert a substantial part of the oxychloride to substances which are less volatile than titanium tetrachloride, removing such substances in condensed state from the titanium tetrachloride in fluid state, and recovering thus purified titanium tetrachloride.

Abstract: A process and apparatus for treating a gas containing a metal halide or an organo substituted metal halide which is drawn into a recovery chamber and is decomposed to a metal precipitate and hydrogen halide by reaction with a warm water spray. Gaseous hydrogen halide is then subjected to a cold water spray to reduce the hydrogen halide gas to an acid which is diluted and discarded as an effluent. The treated gas which is finally discarded to the environment contains substantially no metal halides or organo substituted metal halides and only a minimal concentration of hydrogen halide gas. Metal recovery is enhanced by controlling the pH of the metal oxide and the collected warm water spray and the metal precipitate which is collected in the recovery chamber.

Abstract: Precursors, particularly of non-oxide ceramics, are prepared by special seeding, under carefully controlled conditions. Such procedures can lead to the preparation of unique powders, which may be useful, for example as abrasives, or further processed in special manner to prepare a variety of metal substances. Such procedures can permit final firing to sintered product.

Abstract: The process and apparatus for removing metal halide gases from overspray generated during hot-end glass coating operations is disclosed. The excess metal halide gas is drawn into a recovery chamber in which it is decomposed to a metal oxide and a hydrogen halide gas by reaction with a warm water spray. The hydrogen halide gas is then subjected toa cold water spray to reduce the hydrogen halide gas to an acid which is diluted and discarded as an effluent. The treated overspray gas which is finally discarded to the environment contains substantially no metal halides and only a minimal concentration of hydrogen halide gas.

Abstract: A flue for cooling the flow of reaction product from the high temperature oxidation of a metal halide to the metal oxide in the presence of oxygen, said flue comprising a first section wherein the cross-sectional area is increased thereby decreasing the turbulence of the flow and a second section wherein the cross-sectional area is decreased thereby increasing the velocity or turbulence of the flow and the process for using said flue to produce an agglomerate of TiO.sub.2 particles that are readily filterable and easily ground.

Abstract: In a process for the production of titanium dioxide by the vapour phase oxidation of titanium tetrachloride in which process entrained inert particulate material is passed through equipment used to reduce or prevent the deposition of solids thereon, the quantity of inert particulate material entrained may be affected by the varying back pressure normally obtaining in the equipment. The control of this quantity may be improved by reducing pressure differences (by means of conduit 39) between the inlet (40) and outlet (36) of a mechanical feeding device (29, 30) for the solids. This entails the transmission of the pressure (from the conduit 26) into the solids delivery system 25(17) and this may be alleviated, optionally, by maintaining a head of solids in the system and/or by using a system of pressurized hoppers. The invention enables the quantity of inert particulate material used to be reduced.

Abstract: The residual gas obtained in the pyrogenic production of metal oxides or metalloid oxides contain besides the desired product elemental chlorine if a chlorine containing starting material is employed. After cooling the residual gas the elemental chlorine is reacted to form hydrogen chloride by using an aqueous solution of a reducing agent and in this form the chlorine is subsequently washed out of the residual gas.

Abstract: There is provided a pyrogenic process for the production of finely divided oxide of a metal and/or a metalloid in which there is employed as the starting material a vaporizable halogen compound of a metal and/or metalloid. Because of the starting material there is formed elemental halogen which is an impurity in the oxide formed. To remove the halogen there is supplied to the cooling section of the production plant a mixture of hydrogen and inert gas.

Abstract: There is disclosed an improved process and apparatus for the production of finely-divided metal and metalloid oxides by flame hydrolysis of corresponding metal and metalloid halides whereby fouling of burner apparatus is substantially completely avoided.

Abstract: A titanium oxide resistive-type exhaust gas oxygen sensor having a unique microstructure of interlocked highly irregular, flake-like particles forming a highly durable porous body preferably having a surface area greater than about 3 square meters per gram. A method for producing such particles and forming them into such a high surface area body is also described.

Abstract: Fluid permeable wall members through which an auxiliary fluid is passed against pressure exerted by a fluid to be contained, which wall member is composed of inorganic fibres, may be used to contain hot fluids or fluids otherwise having a deleterious effect on the wall members. Vacuum formed shapes composed of refractory inorganic fibres may be used to contain fluids having temperatures of over 2500.degree. C. such as gases which have been heated by electrical discharge means for use in the vapor phase manufacture of oxides of titanium, iron, aluminium, silicon or zirconium and offer low capital costs combined with resistance to thermal shock.

Abstract: In case of the pyrogenous production of metal oxides or metalloid oxides, whenever a halogen compound is used as a starting material, an elementary halogen is formed as a byproduct. This may be converted in the cooling section of the reaction apparatus with hydrogen into hydrogen halide.For a better temperature control and prevention of uncontrolled deflagration of the hydrogen in case of the halogen detonating gas reaction, according to the invention the hydrogen is introduced into the cooling section by means of a double jacket pipe, whereby an inert gas is introduced additionally by way of the interstice between the inside wall and the outside jacket of the double jacket pipe into the cooling section.