Abstract: A polishing composition having silica-based abrasive grains and a polishing method. A polishing composition having silica particles, wherein on the basis of a colloidal silica dispersion of the silica particles, the dispersion has an Rsp of 0.15 to 0.7 as measured using pulse NMR, and the colloidal silica particles have a shape coefficient SF1 of 1.20 to 1.80, wherein Rsp is calculated based on equation (1): Rsp = ( Rav - Rb ) / ( Rb ) ( 1 ) (wherein Rsp is an index that indicates water affinity; Rav is an inverse of a relaxation time of the colloidal silica dispersion; and Rb is an inverse of a relaxation time of a blank aqueous solution obtained by removing the silica particles from the colloidal silica dispersion), and the shape coefficient SF1 is calculated based on equation (2): SF ? 1 = ( area ? of ? a ? circle ? whose ? diameter ? is ? a ? maximum ? diameter ? of ? the ? particle ) / ( projected ? area ) .

Abstract: A polishing composition having silica-based abrasive grains and a polishing method. A polishing composition having silica particles, wherein on the basis of a colloidal silica dispersion of the silica particles, the dispersion has an Rsp of 0.15 to 0.7 as measured using pulse NMR, and the colloidal silica particles have a shape coefficient SF1 of 1.20 to 1.80, wherein Rsp is calculated based on equation (1): Rsp=(Rav?Rb)/(Rb)??(1) (wherein Rsp is an index that indicates water affinity; Rav is an inverse of a relaxation time of the colloidal silica dispersion; and Rb is an inverse of a relaxation time of a blank aqueous solution obtained by removing the silica particles from the colloidal silica dispersion), and the shape coefficient SF1 is calculated based on equation (2): SF1=(area of a circle whose diameter is a maximum diameter of the particle)/(projected area)??(2).

Abstract: A polishing composition having silica-based abrasive grains and a polishing method. A polishing composition having silica particles, wherein on the basis of a colloidal silica dispersion of the silica particles, the dispersion has an Rsp of 0.15 to 0.7 as measured using pulse NMR, and the colloidal silica particles have a shape coefficient SF1 of 1.20 to 1.80, wherein Rsp is calculated based on equation (1): Rsp=(Rav?Rb)/(Rb)??(1) (wherein Rsp is an index that indicates water affinity; Rav is an inverse of a relaxation time of the colloidal silica dispersion; and Rb is an inverse of a relaxation time of a blank aqueous solution obtained by removing the silica particles from the colloidal silica dispersion), and the shape coefficient SF1 is calculated based on equation (2): SF1=(area of a circle whose diameter is a maximum diameter of the particle)/(projected area)??(2).

Abstract: A polishing composition that is for use in CMP polishing and that makes it possible to minimize the occurrence of defects. A polishing composition comprising silica particles, a basic nitrogen-containing organic compound, and water serving as a solvent, wherein the composition exhibits an Rsp value of the following Formula (1) of more than 0.7 and 6 or less as calculated from values measured by pulse NMR: Rsp=(Rav?Rb)/(Rb) . . . (1) (wherein Rsp is an index of water affinity; Rav is the reciprocal of the relaxation time of the polishing composition; and Rb is the reciprocal of the relaxation time of the water serving as a solvent of the polishing composition).

Abstract: A polishing composition having silica-based abrasive grains and a polishing method. A polishing composition having silica particles, wherein on the basis of a colloidal silica dispersion of the silica particles, the dispersion has an Rsp of 0.15 to 0.7 as measured using pulse NMR, and the colloidal silica particles have a shape coefficient SF1 of 1.20 to 1.80, wherein Rsp is calculated based on equation (1): Rsp=(Rav?Rb)/(Rb)??(1) (wherein Rsp is an index that indicates water affinity; Rav is an inverse of a relaxation time of the colloidal silica dispersion; and Rb is an inverse of a relaxation time of a blank aqueous solution obtained by removing the silica particles from the colloidal silica dispersion), and the shape coefficient SF1 is calculated based on equation (2): SF1=(area of a circle whose diameter is a maximum diameter of the particle)/(projected area)??(2).

Abstract: A method for producing an active silicic acid solution in which the existing amount of foreign matters as plate-like fine particles is reduced and a method for producing a silica sol in which such foreign matters are reduced. The method fulfills the following condition; the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is measured to be 0% to 30% in accordance with measuring method A, the method including the steps of: preparing an active silicic acid solution by subjecting an alkali silicate aqueous solution having a silica concentration of 0.5% by mass to 10.0% by mass to cation-exchange to remove alkaline components; and filtering the active silicic acid solution through a filter whose removal rate of particles having a primary particle size of 1.0 ?m is 50% or more.

Abstract: A method for producing an active silicic acid solution in which the existing amount of foreign matters as plate-like fine particles is reduced and a method for producing a silica sol in which such foreign matters are reduced. The method fulfills the following condition: the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is measured to be 0% to 30% in accordance with measuring method A, the method including the steps of: preparing an active silicic acid solution by subjecting an alkali silicate aqueous solution having a silica concentration of 0.5% by mass to 10.0% by mass to cation-exchange to remove alkaline components; and filtering the active silicic acid solution through a filter whose removal rate of particles having a primary particle size of 1.0 ?m is 50% or more.

Abstract: To provide a method for producing an alkali silicate aqueous solution containing a reduced amount of foreign substance of plate-like fine particles and a method for producing a silica sol containing a reduced amount of foreign substance of plate-like fine particles. A method for producing an alkali silicate aqueous solution fulfilling the following condition: the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is determined to be 0 to 30%. The method for producing an alkali silicate aqueous solution includes the steps of adjusting a silica concentration of an alkali silicate aqueous solution to 0.5 to 10.0% by mass and filtering the alkali silicate aqueous solution through a filter having a removal rate of particles with a primary particle size of 1.0 ?m of 50% or more.

Abstract: A method for producing an active silicic acid solution in which the existing amount of foreign matters as plate-like fine particles is reduced and a method for producing a silica sol in which such foreign matters are reduced. The method fulfills the following condition; the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is measured to be 0% to 30% in accordance with measuring method A, the method including the steps of: preparing an active silicic acid solution by subjecting an alkali silicate aqueous solution having a silica concentration of 0.5% by mass to 10.0% by mass to cation-exchange to remove alkaline components; and filtering the active silicic acid solution through a filter whose removal rate of particles having a primary particle size of 1.0 ?m is 50% or more.

Abstract: To provide a method for producing an alkali silicate aqueous solution containing a reduced amount of foreign substance of plate-like fine particles and a method for producing a silica sol containing a reduced amount of foreign substance of plate-like fine particles. A method for producing an alkali silicate aqueous solution fulfilling the following condition: the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is determined to be 0 to 30%. The method for producing an alkali silicate aqueous solution includes the steps of adjusting a silica concentration of an alkali silicate aqueous solution to 0.5 to 10.0% by mass and filtering the alkali silicate aqueous solution through a filter having a removal rate of particles with a primary particle size of 1.0 ?m of 50% or more.

Abstract: To provide a method for producing an alkali silicate aqueous solution containing a reduced amount of foreign substance of plate-like fine particles and a method for producing a silica sol containing a reduced amount of foreign substance of plate-like fine particles. A method for producing an alkali silicate aqueous solution fulfilling the following condition: the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is determined to be 0 to 30%. The method for producing an alkali silicate aqueous solution includes the steps of adjusting a silica concentration of an alkali silicate aqueous solution to 0.5 to 10.0% by mass and filtering the alkali silicate aqueous solution through a filter having a removal rate of particles with a primary particle size of 1.0 ?m of 50% or more.

Abstract: A silicon carbide substrate polishing composition for polishing a surface of a silicon carbide substrate contains water and colloidal silica particles having a true specific gravity of 2.10 to 2.30, and has a free alkali metal ion concentration of 1 ppm to 150 ppm.

Abstract: A method for producing an active silicic acid solution in which the existing amount of foreign matters as plate-like fine particles is reduced and a method for producing a silica sol in which such foreign matters are reduced. The method fulfills the following condition: the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is measured to be 0% to 30% in accordance with measuring method A, the method including the steps of: preparing an active silicic acid solution by subjecting an alkali silicate aqueous solution having a silica concentration of 0.5% by mass to 10.0% by mass to cation-exchange to remove alkaline components; and filtering the active silicic acid solution through a filter whose removal rate of particles having a primary particle size of 1.0 ?m is 50% or more.

Abstract: To provide a method for producing an alkali silicate aqueous solution containing a reduced amount of foreign substance of plate-like fine particles and a method for producing a silica sol containing a reduced amount of foreign substance of plate-like fine particles. A method for producing an alkali silicate aqueous solution fulfilling the following condition: the existing amount of plate-like fine particles having a length of one side of 0.2 to 4.0 ?m and a thickness of 1 to 100 nm is determined to be 0 to 30%. The method for producing an alkali silicate aqueous solution includes the steps of adjusting a silica concentration of an alkali silicate aqueous solution to 0.5 to 10.0% by mass and filtering the alkali silicate aqueous solution through a filter having a removal rate of particles with a primary particle size of 1.0 ?m of 50% or more.

Abstract: A liquid crystal display device 100 includes a liquid crystal panel 12, a backlight device 14, a first housing 16, and a second housing 18. The backlight device 14 is located to face a rear surface of the liquid crystal panel 12. The first housing 16 supports the liquid crystal panel 12 and has a peripheral portion 22 extending along a periphery of the liquid crystal panel 12. The second housing 18 accommodates the backlight device 14, and has a peripheral portion 24 overlapping an inner surface of the peripheral portion 22 of the first housing 16. An attachment hole 26 is formed in the peripheral portion 24 of the second housing 18. At the peripheral portion 22 of the first housing 16, an attachment piece 28 overlapping, and joined to, an inner surface of the peripheral portion 24 of the second housing 18 through the attachment hole 26 in the peripheral portion 24 of the second housing 18 is provided.

Abstract: There is provided an abrasive used for polishing a substrate which comprises silica as a main component, for example a rock crystal, a quartz glass for photomask, for CMP of an organic film, Inter Layer Dielectric (ILD) and shallow trench isolation of a semiconductor device, or for polishing a hard disk made of glass. A sol which particles are dispersed in a medium, wherein the particles have a particle size of 0.005 to 1 ?m and comprise as a main component crystalline cerium oxide of the cubic system and as an additional component a lanthanum compound, a neodymium compound or a combination thereof, wherein the additional component is contained in X/(Ce+X) molar ratio of 0.001 to 0.5 in which X is lanthanum atoms, neodymium atoms or a combination thereof.

Abstract: The present invention provides an abrasive compound suitable for polishing the surface of a glass substrate for an optical disk platter or a magnetic disk platter. More specifically, the present invention provides an abrasive compound for a glass hard disk platter, characterized as comprising a stable slurry having water and, dispersed therein as an abrasive, cerium(IV) oxide particles having an average secondary particle size of 0.1 to 0.5 ?m and containing CeO2 in a concentration of 0.2 to 30 wt %. Preferably, the present invention provides the above abrasive compound in which cerium amounts for 95% or more in terms of oxides of the total amount of rare earth elements in the abrasive.

Abstract: There is provided an abrasive used for polishing a substrate which comprises silica as a main component, for example a rock crystal, a quartz glass for photomask, for CMP of an organic film, Inter Layer Dielectric (ILD) and shallow trench isolation of a semiconductor device, or for polishing a hard disk made of glass. A sol which particles are dispersed in a medium, wherein the particles have a particle size of 0.005 to 1 ?m and comprise as a main component crystalline cerium oxide of the cubic system and as an additional component a lanthanum compound, a neodymium compound or a combination thereof, wherein the additional component is contained in X/(Ce+X) molar ratio of 0.001 to 0.5 in which X is lanthanum atoms, neodymium atoms or a combination thereof.

Abstract: There is provided an abrasive used for polishing a substrate which comprises silica as a main component, for example a rock crystal, a quartz glass for photomask, for CMP of an organic film, Inter Layer Dielectric (ILD) and shallow trench isolation of a semiconductor device, or for polishing a hard disk made of glass.

Abstract: For aluminum disks and glass-made hard disks, those disks having a mean waviness of less than 3 Å are being desired in order to increase the density of memory capacity. The present invention provides polishing compositions that can give smoothly polished surfaces for the disks. The polishing compositions are polishing compositions for aluminum disks or substrates having silica on the surface thereof, which contain colloidal silica particle groups having different particle size distributions and have a SiO2 concentration of 0.5 to 50% by weight.