Abstract: When a polybasic acid salt containing at least one species selected from the group consisting of an alkaline earth metal, a transition metal, and Al is caused to be present on the surfaces of titanium dioxide fine particles, there are obtained photocatalytic particles and powder exhibiting sufficent photocatalytic properties when irradiated with light from a light source of low quantity of light. By use of the photo-functional particles and powder, an organic polymer composition, a slurry, a coating agent, and a product having a surface exhibiting photocatalytic property and hydrophilicity are obtained.

Abstract: When a polybasic acid salt containing at least one species selected from the group consisting of an alkaline earth metal, a transition metal, and Al is caused to be present on the surfaces of titanium dioxide fine particles, there are obtained photocatalytic particles and powder exhibiting sufficient photocatalytic properties when irradiated with light from a light source of low quantity of light. By use of the photo-functional particles and powder, an organic polymer composition, a slurry, a coating agent, and a product having a surface exhibiting photocatalytic property and hydrophilicity are obtained.

Abstract: A method of producing composite particles of titanium dioxide and a compound inactive as a photocatalyst, comprising the steps of preparing a water based slurry of pH 3 to 5 comprising titanium dioxide, preparing a water based solution comprising a compound inactive as a photocatalyst, and reacting the slurry and the water based solution together at a pH within a range from 4 to 10 is provided, together with highly active photocatalyst particles produced using such a method, and potential uses of such photocatalyst particles.

Abstract: A method of producing composite particles of titanium dioxide and a compound inactive as a photocatalyst, comprising the steps of preparing a water based slurry of pH 3 to 5 comprising titanium dioxide, preparing a water based solution comprising a compound inactive as a photocatalyst, and reacting the slurry and the water based solution together at a pH within a range from 4 to 10 is provided, together with highly active photocatalyst particles produced using such a method, and potential uses of such photocatalyst particles.

Abstract: When a polybasic acid salt containing at least one species selected from the group consisting of an alkaline earth metal, a transition metal, and Al is caused to be present on the surfaces of titanium dioxide fine particles, there are obtained photocatalytic particles and powder exhibiting sufficient photocatalytic properties when irradiated with light from a light source of low quantity of light. By use of the photo-functional particles and powder, an organic polymer composition, a slurry, a coating agent, and a product having a surface exhibiting photocatalytic property and hydrophilicity are obtained.

Abstract: A cerium oxide slurry for polishing comprising cerium oxide dispersed in water, wherein the slurry has a conductivity of about 30 c &mgr;S/cm or less when the cerium oxide concentration in the slurry is c wt. %. In order to adjust the conductivity to about 30 c &mgr;S/cm or less, cerium oxide is washed with deionized water.

Abstract: A photocatalytic titanium dioxide coating composition is described, which comprises (a) finely-divided titanium dioxide particles exhibiting photocatalytic activity, (b) particles of an inorganic compound other than titanium dioxide, or particles of an organic compound convertible to particles of an inorganic compound on firing, (c) a binder, and (d) a solvent. The articles of an inorganic compound have an average particle diameter larger than that of the finely divided titanium dioxide particles and falls within the range of about 0.1 &mgr;m to about 1.0 &mgr;m. The inorganic compound particles are substantially insoluble in the solvent. The amount of the inorganic compound particles is in the range of about 0.5% to about 7% by weight based on the weight of the finely divided titanium dioxide particles. By coating a surface of a substrate with the coating composition, a coating film exhibiting excellent photocatalytic activity and no interference color is formed.

Abstract: A condensed phosphate containing an alkaline earth metal is caused to be present on the surface of titanium dioxide fine particles, and as a result, the condensed phosphate is firmly coupled with the fine particles and is barely liberated from the surface of the fine particles into a medium such as a binder or a resin. As a result, photo-functional particles exhibiting durability and dispersion stability are obtained. By use of the photo-functional particles, a powder and a slurry exhibiting excellent photo-functional property, durability, dispersion stability, and hydrophilicity are produced. In addition, by use of the powder and slurry, a polymer composition, a coating agent, a photo-functional formed article, and a photo-functional structure are produced.

Abstract: A cerium oxide slurry for polishing comprising cerium oxide dispersed in water, wherein the slurry has a conductivity of about 30c &mgr;S/cm or less when the cerium oxide concentration in the slurry is c wt. %. In order to adjust the conductivity to about 30c &mgr;S/cm or less, cerium oxide is washed with deionized water.

Abstract: A cerium oxide slurry for polishing comprising cerium oxide dispersed in water, wherein the slurry has a conductivity of about 30c &mgr;S/cm or less when the cerium oxide concentration in the slurry is c wt.%. In order to adjust the conductivity to about 30c &mgr;S/cm or less, cerium oxide is washed with deionized water.

Abstract: An object of the present invention is to provide a transparent noise-barrier wall which is slow to foul, easy to clean even when fouled, and capable of maintaining these effects over a long period of time. The transparent noise-barrier wall has brookite titanium dioxide substantially existing on the surface. The titanium dioxide particles preferably contain about 20% by mass or more of brookite titanium dioxide.