Abstract: The present invention provides a zirconium element-containing resin composition capable of achieving both high transparency and a high refractive index. The present invention is a zirconium element-containing resin composition containing a zirconium element-containing metal oxide (A); a dispersant (B); and a polymerizable resin (C), in which the zirconium element-containing metal oxide (A) has an average particle diameter of 20 nm or less as measured by a dynamic light scattering method, and the dispersant (B) contains a compound represented by the following formula (1), the zirconium element-containing resin composition may contain a silane coupling agent, and a content ratio of the silane coupling agent is less than 30 parts by mass with respect to 100 parts by mass of a total of the compound represented by the formula (1) and the silane coupling agent.

Abstract: The present invention provides a boron-containing silica dispersion having better dispersion stability at a high concentration, and higher binding properties between boron and silica than conventional dispersions. The present invention is a boron-containing silica dispersion containing amorphous silica particles containing boron atoms and a dispersion medium; the boron-containing amorphous silica particles having an average particle size of 10 to 100 nm, as determined from 40 particles selected at random in a transmission electron micrograph; the boron-containing silica dispersion having a solids content of 5 to 30 mass %; and the boron-containing silica dispersion having a sedimentation rate of the particles of 4% or less, when the boron-containing silica dispersion is left standing for 1000 hours, and proportions of SiO2 and B2O3 of 90.0 to 99.8 mass % and 0.2 to 10.

Abstract: Provided is a boron-containing amorphous silica powder more excellent in terms of low temperature sinterability than conventional silica powders. The present invention relates to amorphous silica powder containing boron atoms, the boron-containing amorphous silica powder having an average particle size of 10 to 100 nm, as determined from 40 particles selected at random in a transmission electron micrograph, the boron-containing amorphous silica powder having a decrement in a boron content of 10 mass % or less, when fired under the following conditions: <Firing conditions> 5 to 10 g of a dried product of the boron-containing amorphous silica powder is filled into an alumina crucible, heated in the atmosphere at 200° C./hour to 1000° C. to 1100° C., maintained as it is for 5 hours, and cooled to room temperature.

Abstract: The present invention relates to fine barium sulfate powder that can be readily and simply dispersed in resins or solvents; a resin composition, a coating composition, an ink composition, and a resin molded article each containing the barium sulfate powder; and a method for producing the barium sulfate powder. Provided is barium sulfate powder having a number average primary particle size of 1 to 100 nm, the powder including an organic compound on its surface, the powder in the form of compressed compact having a contact angle with distilled water of 10 to 170 degrees.

Abstract: The invention provides a low alpha dose barium sulfate particle having a silica content of 0.6% by weight or less, an average particle diameter of 1 ?m or less, a sulfur content of 10 ppm or less, and an alpha dose of 0.07 cph/cm2 or less.

Abstract: The present invention relates to fine barium sulfate powder that can be readily and simply dispersed in resins or solvents; a resin composition, a coating composition, an ink composition, and a resin molded article each containing the barium sulfate powder; and a method for producing the barium sulfate powder. Provided is barium sulfate powder having a number average primary particle size of 1 to 100 nm, the powder including an organic compound on its surface, the powder in the form of compressed compact having a contact angle with distilled water of 10 to 170 degrees.

Abstract: The invention provides a low alpha dose barium sulfate particle having a silica content of 0.6% by weight or less and an alpha dose of 0.07 cph/cm2 or less.

Abstract: The invention provides a low alpha dose barium sulfate particle having a silica content of 0.6% by weight or less and an alpha dose of 0.07 cph/cm2 or less.

Abstract: The invention provides a low alpha dose barium sulfate particle having a silica content of 0.6% by weight or less, an average particle diameter of 1 ?m or less, a sulfur content of 10 ppm or less, and an alpha dose of 0.07 cph/cm2 or less.