Abstract: A dispersion wherein dispersoid particles including colloidal silica and zinc cyanurate are dispersed in a liquid medium. The colloidal silica particles may have an average diameter of 5 to 500 nm, and the dispersion may contain 0.1 to 40% by mass of the particles in terms of SiO2 concentration. Primary particles of the zinc cyanurate may have a major axis length of 50 to 1000 nm, a minor axis length of 10 to 300 nm, and a ratio of major to minor axis length of 2 to 25, and the dispersion may contain 0.1 to 50% by mass of the particles in terms of solids content. A mass ratio of the colloidal silica to the zinc cyanurate particles may be 1:0.01 to 100, and total solids content may be 0.1 to 50% by mass. The liquid medium may be water or an organic solvent.

Abstract: A coating-forming composition for an electrical steel sheet that maintains excellent insulating properties, corrosion resistance, adhesion, and the like required in a coating for an electrical steel sheet, and exhibits excellent viscosity stability, with an increase in viscosity over time being kept gradual. A coating-forming composition for an electrical steel sheet comprises colloidal silica, a phosphate, phenylphosphonic acid or a salt thereof, and an aqueous medium.

Abstract: A coating-forming composition for an electrical steel sheet that maintains excellent insulating properties, corrosion resistance, adhesion, and the like required in a coating for an electrical steel sheet, and exhibits excellent viscosity stability, with an increase in viscosity over time being kept gradual. A coating-forming composition for an electrical steel sheet comprises colloidal silica, a phosphate, phenylphosphonic acid or a salt thereof, and an aqueous medium.

Abstract: The ?-eucryptite fine particle production method of the invention includes spraying, into an atmosphere at 50° C. to a temperature lower than 300° C., a solution containing a water-soluble lithium salt, a water-soluble aluminum salt, and colloidal silica, in such amounts that the mole proportions among lithium atoms, aluminum atoms, and silicon atoms (Li:Al:Si) are adjusted to 1:1:1, to thereby dry the solution, and, subsequently, firing the dried product in air at 600 to 1,300° C.

Abstract: The ?-eucryptite fine particle production method of the invention includes spraying, into an atmosphere at 50° C. to a temperature lower than 300° C., a solution containing a water-soluble lithium salt, a water-soluble aluminum salt, and colloidal silica, in such amounts that the mole proportions among lithium atoms, aluminum atoms, and silicon atoms (Li:Al:Si) are adjusted to 1:1:1, to thereby dry the solution, and, subsequently, firing the dried product in air at 600 to 1,300° C.

Abstract: There is provided a polishing liquid composition that can effectively reduce LPDs having a size of 50 nm or less on a wafer surface in polishing of semiconductor wafers. A semiconductor wafer polishing liquid composition including: water; silica particles; an alkaline compound; a water-soluble polymer compound; and polyethylene glycol, wherein the semiconductor wafer polishing liquid composition satisfies conditions (a) to (c): (a) a shape factor SF1 of the silica particles is 1.00 to 1.20, (b) a mean primary particle diameter of the silica particles that is obtained by a nitrogen adsorption method is 5 nm to 100 nm, and a coefficient of particle diameter variation CV value obtained from image analysis of the transmission electron microscope image is in a range of 0% to 15%, and (c) the polyethylene glycol has a number average molecular weight of 200 to 15,000.

Abstract: The present invention relates to a polishing composition for silicon wafer comprising silica, a basic compound, a polyaminopolycarboxylic acid compound having hydroxy group, and water. The polishing composition can prevent metal contamination by nickel, chromium, iron, copper or the like, particularly copper contamination in polishing of silicon wafer.

Abstract: The present invention relates to a polishing composition for silicon wafer comprising silica; a basic compound; at least one compound selected from the group consisting of amino acid derivatives represented by formula (1) wherein R1, R2 and R3 are identical or different one another, C1-12alkylene group that may be substituted by hydroxyl group, carboxyl group, phenyl group or amino group, and formula (2) wherein R4 and R5 are identical or different each other, hydrogen atom, or C1-12alkyl group that may be substituted by hydroxyl group, carboxyl group, phenyl group or amino group, with a proviso that both R4 and R5 are not hydrogen at the same time, and R6 is C1-12alkylene group that may be substituted by hydroxyl group, carboxyl group, phenyl group or amino group, and the salts of the amino acid derivatives; and water. The polishing composition can prevent metal contamination, particularly copper contamination in polishing of silicon wafer.

Abstract: A stable silica sol having an SiO2 concentration of 1 to 50% by weight and containing liquid-medium dispersed moniliform colloidal silica particles each having 3 or more as a ratio of D1/D2 of a particle diameter (D1 nm) measured by a dynamic light scattering method to a mean particle diameter (a particle diameter measured by a nitrogen absorption method: D2 nm) where D1 is 50 to 500 nm, and which are comprised by spherical colloidal silica particles having a mean particle diameter of 10 to 80 nm and metal oxide-containing silica bonding these spherical-colloidal silica particles, and in which the spherical colloidal silica particles link in rows in only one plane, process for producing such and a coating composition for ink receiving layers containing such a silica sol and an ink jet recording medium.

Abstract: The present invention relates to a polishing composition for polishing alumina disks, polishing substrates having silica surfaces and semiconductor wafers, comprising a stable aqueous silica sol containing moniliform colloidal silica particles having a ratio (D1/D2) of a particle diameter D1 nm (as measured by dynamic light scattering method) to a mean particle diameter D2 (as measured by nitrogen absorption method) of 3 or more, wherein D1 is between 50 to 800 nm and D2 is between 10 to 120 nm, said moniliform colloidal silica particles being composed of spherical colloidal silica particles and a metal oxide-containing silica bond which bonds these spherical colloidal silica particles together, wherein the spherical colloidal silica particles are linked together in rows in only one plane by observation through an electron microscope, and further wherein said polishing composition contains 0.5 to 50% by weight of said moniliform colloidal silica particles.

Abstract: A process for producing a stable acidic aqueous alumina sol containing 50 to 300 nm of elongate secondary particles which are elongated in only one plane and formed by edge-to-edge coagulation of rectangular plate-like primary particles having a length of one side of 10 to 30 nm when observed through an electron microscope, the process comprises the steps of:(A) adding an alkali to an aqueous alumina sol containing fibrous colloidal particles of an amorphous alumina hydrate to produce a reaction mixture having a pH of 9 to 12,(B) subjecting the reaction mixture obtained in the step (A) to a hydrothermal treatment at a temperature of 110 to 250.degree. C. to produce an aqueous suspension containing an alumina hydrate having a boehmite structure, and(C) desalting the aqueous suspension obtained in the step (B) by adding water and an acid by ultrafiltration to form an acidic aqueous alumina sol having a pH of 3 to 6.

Abstract: A method for preparing a silica sol having an elongated shape comprising a step (a) where an aqueous solution containing a water-soluble calcium salt or a water-soluble magnesium salt or a mixture of the water-soluble calcium salt or the water-soluble magnesium salt is mixed with an aqueous colloidal solution of an active silicic acid; a step (b) where an alkaline substance is mixed with the aqueous liquid obtained in the step (a); a step (c) where a part or the whole of the mixture obtained in the step (b) is heated at 60.degree. C. or higher to obtain a heel solution and a feed solution is prepared by a part of the mixture obtained in the step (b) or a mixture separately prepared by the step (b) and the feed solution is added to the heel solution; and a step where water is evaporated during said addition step so that SiO.sub.2 concentration is concentrated to 6 to 30% by weight.

Abstract: A sol of flat silica particles (100-1000 nm in size) is produced by the following steps (a) to (d) from an acidic aqueous sol (S.sub.0) of negatively charged silica particles (7-30 nm in diameter) and an aqueous solution (B) of basic aluminum or zirconium salt.(a) mixing 100 parts by weight (as SiO.sub.2) of the sol (S.sub.0) with 0.2-10 parts by weight (as Al.sub.2 O.sub.3 or ZrO.sub.2) of the aqueous solution (B), and adjusting the resulting sol to pH 4-7, thereby yielding a sol (S.sub.1),(b) mixing 100 parts by weight (as SiO.sub.2) of the sol (S.sub.1) with 20-200 parts by weight (as SiO.sub.2) of the sol (S.sub.0), and adjusting the resulting sol to pH 4-7, thereby yielding a sol (S.sub.2),(c) mixing 100 parts by weight (as SiO.sub.2) of the sol (S.sub.2) with the aqueous solution (B) in an amount corresponding to 2-50% of the amount (as Al.sub.2 O.sub.3 or ZrO.sub.2 in parts by weight) added to 100 parts by weight (as SiO.sub.2) of the sol (S.sub.