Abstract: A process for wet pulverizing mesoporous silica particles while a surfactant exists in mesopores, and mesoporous silica particles having an average particle diameter of 1 ?m or less, wherein the volume of mesopores having a diameter of 2 to 50 nm is 0.7 mL/g or more and the geometric standard deviation of a mesopore distribution is 2.0 or less. Mesoporous silica particles having a particle diameter in a submicron order can be obtained at a high yield without causing the marked collapse of mesopores and can be produced efficiently by using an ordinary pulverizer and safely by using an aqueous medium. The mesoporous silica particles having an average particle diameter of 1 ?m or less are useful as an ink absorbent for ink jet recording paper, low-dielectric film, catalyst support, separating agent, adsorbent and medical carrier for medicines.

Abstract: A process for wet pulverizing mesoporous silica particles while a surfactant exists in mesopores, and mesoporous silica particles having an average particle diameter of 1 ?m or less, wherein the volume of mesopores having a diameter of 2 to 50 nm is 0.7 mL/g or more and the geometric standard deviation of a mesopore distribution is 2.0 or less. Mesoporous silica particles having a particle diameter in a submicron order can be obtained at a high yield without causing the marked collapse of mesopores and can be produced efficiently by using an ordinary pulverizer and safely by using an aqueous medium. The mesoporous silica particles having an average particle diameter of 1 ?m or less are useful as an ink absorbent for ink jet recording paper, low-dielectric film, catalyst support, separating agent, adsorbent and medical carrier for medicines.

Abstract: A process for wet pulverizing mesoporous silica particles while a surfactant exists in mesopores, and mesoporous silica particles having an average particle diameter of 1 ?m or less, wherein the volume of mesopores having a diameter of 2 to 50 nm is 0.7 mL/g or more and the geometric standard deviation of a mesopore distribution is 2.0 or less. In the above process, mesoporous silica particles having a particle diameter in a submicron order can be obtained at a high yield without causing the marked collapse of mesopores and can be produced efficiently by using an ordinary pulverizer and safely by using an aqueous medium. The mesoporous silica particles having an average particle diameter of 1 ?m or less are useful as an ink absorbent for ink jet recording paper, low-dielectric film, catalyst support, separating agent, adsorbent and medical carrier for medicines.

Abstract: Provided is a cationized silica dispersion prepared by dispersing dry processed silica and a cationic resin in a polar solvent, wherein a concentration of dissolved silicic acid at 25° C. is 200 ppm or less. This cationized silica dispersion does not substantially form coagulated matters when blended with a binder and therefore can advantageously be used for producing a coating composition such as a coating composition for forming a gas barrier layer, a corrosion preventive coating composition and a coating composition for ink jet recording paper.

Abstract: Provided is a cationized silica dispersion prepared by dispersing dry processed silica and a cationic resin in a polar solvent, wherein a concentration of dissolved silicic acid at 25° C. is 200 ppm or less. This cationized silica dispersion does not substantially form coagulated matters when blended with a binder and therefore can advantageously be used for producing a coating composition such as a coating composition for forming a gas barrier layer, a corrosion preventive coating composition and a coating composition for ink jet recording paper.

Abstract: A boron nitride fiber comprising hexagonal and/or turbostratic boron nitride having C planes oriented substantially parallel to the fiber axis and a degree of orientation of 0.74 or above can be obtained by heating an adduct between a boron trihalide such as boron trichloride or the like and a nitrile compound such as acetonitrile, benzonitrile or the like, and an ammonium halide or a primary amine hydrohalide in the presence of a boron trihalide at around 125.degree. C. to form a boron nitride precursor, dissolving the boron nitride precursor in a solvent such as N,N'-dimethyl formamide or the like, capable of dissolving the precursor, spinning the solution to obtain a boron nitride precursor fiber, heat-treating the precursor fiber in an inert gas atmosphere and then in an ammonia gas atmosphere to obtain a boron nitride fiber, and heat-treating the boron nitride fiber with a tensile stress being applied to the fiber. The boron nitride fiber of the present invention has a degree of orientation of 0.

Abstract: A tin oxide fiber expressed by the general formulaSn.sub.(1-y) Z.sub.y O.sub.2 (I)wherein Z is a metal element of the Group V of the periodic table, and y is 0 to 0.3, having a diameter which is greater than 1 .mu.m or having a length which is greater than 3 mm and having an aspect ratio which is greater than 10.This fiber is process for producing a tin oxide fiber comprising spinning an alcohol solution of a tin compound soluble in alcohol, or spinning an alcohol solution of said tin compound and a compound of a metal of the Group V of the periodic table that is soluble in alcohol, followed by heating.

Abstract: Disclosed is a cathode comprising an active layer composed of a nickel/tin alloy having a nickel content of 25 to 99% by weight, which is formed on the surface of an electrically conductive electrode substrate. When this cathode is used for generating hydrogen by the electrolysis, the hydrogen overvoltage is controlled to a very low level. This active layer is formed by co-electro-deposition of Ni and Sn from a plating solution containing Ni and Sn ions or by thermal decomposition of a mixture containing a nickel compound and a tin compound.