Abstract: A method for coating the surface of inorganic solid particles in an aqueous suspension, particularly for coating titanium dioxide with SiO2 includes: a) disagglomeration of the solid particles contained in aqueous suspension, b) addition of a water-soluble precursor of the coating substance to the suspension, c) immediately following step b) homogenization of the suspension, where the temperature and pH value of the suspension do not change significantly in steps a) to c), d) feeding the slurry into a tank and precipitation of the coating substance onto the particle surface and, optionally, application of further coatings, and e) separation of the solid particles from the suspension. The method produces to a highly homogeneous and continuous skin on the particle surface, and to less separately precipitated coating substance.

Abstract: A method of predicting photostability of coatings with various dopants on titanium dioxide pigment particles is disclosed. Calculations of the density of states show that a doped coating which reduces the density of states near the band edge or increases the density of states within the band gap of the pigment particles increases the photostability of the doped pigment.

Abstract: A method of predicting photostability of coatings with various dopants on titanium dioxide pigment particles is disclosed. Calculations of the density of states show that a doped coating which reduces the density of states near the band edge or increases the density of states within the band gap of the pigment particles increases the photostability of the doped pigment.

Abstract: The invention relates to a rutile titanium dioxide pigment for use in decorative laminating papers that yields higher opacity of the papers compared to the prior art, as well as a method for its manufacture. The pigment displays a surface coating that contains aluminum phosphate, aluminum oxide, silicon oxide and titanium oxide. The silicon oxide is precipitated in fluffy form. The coated particles display a BET value of at least 15 m2/g. The manufacturing method is characterized in that an aluminum and a phosphorus component are first added to a TiO2 suspension. Thereafter, an alkaline silicon component, an acid-reacting titanium component and, optionally, a further pH-regulating component are added, the pH value being set in the range from 4 to 9 in this context.

Abstract: A method of predicting photostability of coatings with various dopants on titanium dioxide pigment particles is disclosed. Calculations of the density of states show that a doped coating which reduces the density of states near the band edge or increases the density of states within the band gap of the pigment particles increases the photostability of the doped pigment.

Abstract: A method of predicting photostability of coatings with various dopants on titanium dioxide pigment particles is disclosed. Calculations of the density of states show that a doped coating which reduces the density of states near the band edge or increases the density of states within the band gap of the pigment particles increases the photostability of the doped pigment.

Abstract: A weather-resistant titanium dioxide pigment particularly suitable for use in engineering plastics, as well as to a method for its manufacture and to polymers containing the pigment. The titanium dioxide is provided with a surface coating that, from the inside to the outside, displays a SiO2 layer, an Al2O3 layer and an organic layer, where the maximum total Al2O3 content is 2.4% by weight and the organic layer contains at least one compound from the group comprising H-siloxanes, silicone oils and organically functionalised polysiloxanes. The manufacturing method is characterised in that an aqueous suspension of Al-doped titanium dioxide particles is milled in an agitator mill, and a SiO2 layer and an Al2O3 layer are then applied in batch mode, after which an organic layer is applied that contains at least one compound from the group comprising H-siloxanes, silicone oils and organically functionalised polysiloxanes.

Abstract: The invention relates to a weather resistant titanium dioxide pigment with good optical properties having a SiO2 dense skin doped with metal atoms. Particularly suitable elements for doping are tin, zirconium and titanium. The SiO2 dense skin is composed of multiple layers whereby the innermost layer does not contain any significant quantity of metal atoms. The coating according to the invention is produced by adding the components to the alkaline suspension (pH at least 9) one after the other with a sliding pH. Complete formation of the doped SiO2 dense skin requires that the pH subsequently be lowered to below 9. The pigment is particularly suitable for use in surface coatings and plastics.

Abstract: A method for coating the surface of inorganic solid particles in an aqueous suspension, particularly for coating titanium dioxide with SiO2 includes: a) disagglomeration of the solid particles contained in aqueous suspension, b) addition of a water-soluble precursor of the coating substance to the suspension, c) immediately following step b) homogenization of the suspension, where the temperature and pH value of the suspension do not change significantly in steps a) to c), d) feeding the slurry into a tank and precipitation of the coating substance onto the particle surface and, optionally, application of further coatings, and e) separation of the solid particles from the suspension. The method produces to a highly homogeneous and continuous skin on the particle surface, and to less separately precipitated coating substance.

Abstract: A method for manufacturing inorganic solid particles, particularly titanium dioxide pigment particles, with a smooth and homogeneous surface coating in an aqueous suspension.

Abstract: A coated titanium dioxide pigment with good opacity and simultaneously good retention for use in decorative laminating paper characterized by a surface coating containing aluminum oxide phosphate and attached hollow bodies, e.g., hollow microbodies. A manufacturing method is characterized in that an aluminum containing component and a phosphorus containing component are first added to a TiO2 suspension, during which time the pH value does not drop below 10. The hollow bodies are subsequently added, followed by addition of at least one acidic component, as a result of which the pH value of the suspension is lowered to the range from about 4 to 9. In an alternative embodiment of the method, the suspension has a pH value of under 4 at the time of addition of the aluminum containing component and a phosphorus containing component.

Abstract: A coated titanium dioxide pigment with good opacity and simultaneously good retention for use in decorative laminating paper characterized by a surface coating containing aluminium oxide phosphate and attached hollow bodies, e.g., hollow microbodies. A manufacturing method is characterized in that an aluminium containing component and a phosphorus containing component are first added to a TiO2 suspension, during which time the pH value does not drop below 10. The hollow bodies are subsequently added, followed by addition of at least one acidic component, as a result of which the pH value of the suspension is lowered to the range from about 4 to 9. In an alternative embodiment of the method, the suspension has a pH value of under 4 at the time of addition of the aluminium containing component and a phosphorus containing component.

Abstract: A method of predicting photostability of coatings with various dopants on titanium dioxide pigment particles is disclosed. Calculations of the density of states show that a doped coating which reduces the density of states near the band edge or increases the density of states within the band gap of the pigment particles increases the photostability of the doped pigment.

Abstract: The invention relates to a rutile titanium dioxide pigment for use in decorative laminating papers that yields higher opacity of the papers compared to the prior art, as well as a method for its manufacture. The pigment displays a surface coating that contains aluminium phosphate, aluminium oxide, silicon oxide and titanium oxide. The silicon oxide is precipitated in fluffy form. The coated particles display a BET value of at least 15 m2/g. The manufacturing method is characterized in that an aluminium and a phosphorus component are first added to a TiO2 suspension. Thereafter, an alkaline silicon component, an acid-reacting titanium component and, optionally, a further pH-regulating component are added, the pH value being set in the range from 4 to 9 in this context.

Abstract: A method of predicting photostability of coatings with various dopants on titanium dioxide pigment particles is disclosed. Calculations of the density of states show that a doped coating which reduces the density of states near the band edge or increases the density of states within the band gap of the pigment particles increases the photostability of the doped pigment.

Abstract: A method and material for improved TiO2 pigment for paper and laminates is described. Phosphorous, titanium, and aluminum compounds are successively added to a TiO2 pigment suspension. Resulting pigments show improved greying resistance and hiding power over prior art pigments, and show improved results as pigments in tests of paper and laminates.

Abstract: The invention relates to a method for the surface treatment of a titanium dioxide that leads to pigments with improved retention and improved opacity, where consistently high opacity can be obtained using less pigment. The method is characterised in that an aluminium component and a phosphorus component are first added to a TiO2 suspension, during which process its pH value does not drop below 10. The pH value of the suspension is subsequently lowered to below 9 by adding an acid component. The pigment produced by the method according to the invention is eminently suited to use in decorative laminating paper.

Abstract: The invention relates to a method for the post-treatment of titanium dioxide, in order to produce particularly weather-resistant titanium dioxide pigments with good optical properties. The method is characterized in that, together with the hydrous oxides of tin and zirconium, at least one other from the group comprising aluminium, silicon and titanium is additionally precipitated onto the particle surface. The post-treatment components are added to the aqueous TiO2 suspension either in the acidic range (pH value of 3 at most) or in the alkaline range (pH value of 10 at least). The pH value is subsequently set to between 6 and 8. Final tempering of the pigment at elevated temperatures from over 125° C. to up to 500° C. can improve the tone b. The pigment is particularly suitable for use in paints, coatings and plastics.

Abstract: The invention relates to a weather resistant titanium dioxide pigment with good optical properties having a SiO2 dense skin doped with metal atoms. Particularly suitable elements for doping are tin, zirconium and titanium. The SiO2 dense skin is composed of multiple layers whereby the innermost layer does not contain any significant quantity of metal atoms. The coating according to the invention is produced by adding the components to the alkaline suspension (pH at least 9) one after the other with a sliding pH. Complete formation of the doped SiO2 dense skin requires that the pH subsequently be lowered to below 9. The pigment is particularly suitable for use in surface coatings and plastics.

Abstract: The invention relates to a method for the post-treatment of titanium dioxide, in order to produce particularly weather-resistant titanium dioxide pigments with good optical properties. The method is characterised in that, together with the hydrous oxides of tin and zirconium, at least one other from the group comprising aluminium, silicon and titanium is additionally precipitated onto the particle surface. The post-treatment components are added to the aqueous TiO2 suspension either in the acidic range (pH value of 3 at most) or in the alkaline range (pH value of 10 at least). The pH value is subsequently set to between 6 and 8. Final tempering of the pigment at elevated temperatures from over 125° C. to up to 500° C. can improve the tone b. The pigment is particularly suitable for use in paints, coatings and plastics.