An inorganic oxide particles which have a minute particle diameter at which no interference fringes occur in a coating film and high transparency can be secured even when applied to a high refractive index substrate, and in which excitation by ultraviolet radiation is almost completely suppressed, a coating composition containing such particles, and an optical member having a cured film formed from the coating composition. Inorganic oxide particles obtained by bonding an organosilicon compound having a nitrogen-containing heterocyclic group to the surface of modified metal oxide colloid particles (C) having an average particle diameter of 2 to 100 nm, which include metal oxide colloid particles (A) having an average primary particle diameter of 2 to 60 nm as nuclei and with the nuclei surface coated with a coating composed of inorganic oxide colloid particles (B) having an average primary particle diameter of 1 to 4 nm.

The present invention is a multilayered composite comprising porous metal oxide particles that are covalently bonded by way of inorganic ether groups to one or more sites of a first polyhydroxyl-functionalized polymer. This first polymer is in turn covalently bonded by way of inorganic ether groups to one or more sites of a second polyhydroxyl-functionalized polymer. The multilayered composites can be prepared by contacting porous inorganic-oxide particles with a sufficient amount of OH-reactive crosslinking agent to form metal oxide particles imbibed with the crosslinking agent, and then contacting the inorganic-oxide particles with a solution of polyhydroxyl-functionalized polymer under reactive conditions.

Hollow structure particles which contain titanium oxide and silica, in which the crystal type of the titanium oxide is rutile type; a method for producing the hollow structure particles; a white ink which contains these hollow structure particles as a coloring agent; use of the white ink in inkjet recording; and an inkjet recording method which uses the white ink.

Aqueous dispersion containing a hydrophilic metal oxide powder comprising a metal oxide and a surface modification of the metal oxide, wherein a) the metal oxide is selected from the group consisting of TiO.sub.2, ZrO.sub.2, SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2O.sub.3, Fe.sub.3O.sub.4, Sb.sub.2O.sub.3, WO.sub.3, CeO.sub.2 and mixed oxides thereof and b) the surface modification b1) comprises silicon atoms and aluminum atoms and b2) the silicon atoms are at least partly bonded to a hydrocarbon radical via a C atom and b3) the Al/Si molar ratio of the surface modification is 1:2-1:20.

A reflective particulate material includes a particulate substrate having high total solar reflectance, bulk and apparent densities and toughness, and a low dust index. The reflective particulate can have a total solar reflectance of 80% to 87%, a toughness of 1% or fewer fines, an apparent density of 2.75 g/cm.sup.3 or greater, and a dust index of 1 or lower. A method of manufacturing the reflective particulate material includes preparing a slurry of the particulate substrate, spray drying the slurry to form a spray dried particulate, crushing the spray dried particulate to form a crushed particulate, and heating/calcining the crushed particulate. The heated, crushed particulate may further be coated to form a coated roofing granule.

A particulate metal oxide has a metal oxide core and a coating layer containing an inorganic material and (i) a quaternary silane coupling agent, and/or (ii) a silane coupling agent and a hydrophobizing agent. Preferred materials are titanium dioxide core particles, an amino organosilane coupling agent and a fatty acid hydrophobizing agent. The particulate metal oxide is suitable for use in forming a dispersion, and the particles and dispersion can be used in an end-use sunscreen composition which is transparent, exhibits effective UV absorption properties, reduced photoactivity, and/or improved skin feel.

Disclosed are a glossy pigment having a hollow structure and a method for producing the same. The glossy pigment having a hollow structure according to the present invention comprises: a hollow which penetrates through the center of the inside thereof; and a metal oxide coating layer which covers a part or all of the hollow, wherein the metal oxide coating layer has a hollow structure having a thickness of 0.1-3 m.

Provided are a titanium dioxide aqueous dispersion having high dispersibility and little aggregation or coarse particles, and a method for producing the same. The titanium dioxide aqueous dispersion contains titanium dioxide particles having a hydrophobic compound such as a higher fatty acid or a salt thereof on the surface, an aqueous dispersion medium, a nonionic surfactant having an HLB value of 10 or higher, and a basic compound such as an alkanolamine, and the pH is in the 8.5-13 range. The method for producing a titanium dioxide aqueous dispersion has a step for mixing the titanium dioxide particles having a hydrophobic compound on the surface, the aqueous dispersion medium, the nonionic surfactant having an HLB value of 10 or higher, and the basic compound to bring the pH of the aqueous dispersion into the 8.5-13 range.

A process is provided for the preparation of lacing resistant, titanium dioxide particles for use in photodurable thin film production. Said process involves dewatering titanium dioxide particles that have been encapsulated with a layer of amorphous alumina in continuous fashion at temperatures in excess of 100 C.

The invention relates to a method for preparing durable titanium dioxide particles. The preparation process includes an aqueous grinding step, which comprising providing an aqueous slurry or dispersion comprising titanium dioxide particles, aluminum containing compound and phosphorous containing compound into grinding equipment. The slurry or dispersion is subjected to an aqueous grinding process, and subsequently titanium dioxide particles having a core of titanium dioxide and a pre-coating layer thereon is obtained, said pre-coating layer containing aluminum and phosphorous containing compounds. The invention further covers the resulting titanium dioxide particles and uses thereof.