616 results about "Colloidal Silicon Dioxide" patented technology

A coating admixture, method of coating and substrates coated thereby, wherein the coating contains colloidal silica, colloidal alumina, or combinations thereof; a filler such as silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide and boron oxide; and one or more emissivity agents such as silicon hexaboride, carbon tetraboride, silicon tetraboride, silicon carbide, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, or metallic oxides such as iron oxides, magnesium oxides, manganese oxides, chromium oxides, copper chromium oxides, cerium oxides, terbium oxides, and derivatives thereof. In a coating solution, an admixture of the coating contains water. A stabilizer such as bentonite, kaolin, magnesium alumina silicon clay, tabular alumina and stabilized zirconium oxide is also added.

An improved composition and method for polishing a sapphire surface is disclosed. The method comprises abrading a sapphire surface, such as a C-plane or R-plane surface of a sapphire wafer, with a polishing slurry comprising an abrasive amount of an inorganic abrasive material such as colloidal silica suspended in an aqueous medium having a salt compound dissolved therein. The aqueous medium has a basic pH and includes the salt compound in an amount sufficient to enhance the sapphire removal rate relative to the rate achievable under the same polishing conditions using a the same inorganic abrasive in the absence of the salt compound.

A microcrystalline cellulose-based excipient having improved compressibility, whether utilized in direct compression, dry granulation or wet granulation formulations, is disclosed. The excipient is an agglomerate of microcrystalline cellulose particles and from about 0.1% to about 20% silicon dioxide particles, by weight of microcrystalline cellulose, wherein the microcrystalline cellulose and silicon dioxide are in intimate association with each other. The silicon dioxide utilized in the novel excipient has a particle size from about 1 nanometer to about 100 microns. Most preferably, the silicon dioxide is a grade of colloidal silicon dioxide. An extra low moisture excipient is provided which exhibits improved compressibility as compared to conventional microcrystalline cellulose, while providing a moisture content of from about 0.5 to 2.5% LOD, preferably between about 0.5 and about 1.8%, more preferably between 0.8 and 1.5%, and most preferably between about 0.8 and about 1.2 %.

A polishing composition includes silicon dioxide, an alkaline compound, an anionic surfactant, and water. The silicon dioxide is, for example, colloidal silica, fumed silica, or precipitated silica. The alkaline compound is, for example, potassium hydroxide, sodium hydroxide, ammonia, tetramethylammonium hydroxide, piperazine anhydride, or piperazine hexahydrate. The anionic surfactant is at least one selected from a sulfonic acid surfactant, a carboxylic acid surfactant, and a sulfuric acid ester surfactant. The polishing composition can be suitably used in applications for polishing a silicon wafer.

A water-based coating is described comprising colloidal silica and lamellar materials such as glass flakes or mica admixed with a water-based film-forming polymeric carrier such as an epoxy. The water-based epoxy coating can be directly applied to unset, set, cured or uncured concrete and exhibits a water vapor permeance of about 0.14 perms by ASTM F-1869-04. A method for using the coating is also disclosed.

A metal-polishing composition includes colloidal silica particles, which has a ratio of minor axis/major axis of 0.2 to 0.8 and a surface at least partially covered with aluminum atoms, comprises in an amount of 50% or more with respect to total abrasives. The metal-polishing composition preferably includes an oxidizing agent, an organic acid or the like. The colloidal silica constituting the colloidal silica particles is preferably formed by hydrolysis of alkoxysilane. The major axis of the colloidal silica particles is preferably in a range of 20 nm to 100 nm.

A diluted slurry supplying apparatus utilized in a polishing apparatus for finishing a semiconductor wafer with a slurry containing colloidal silica and water-soluble polymer is provided. The polishing method comprises: a slurry supplier capable of supplying the slurry containing the colloidal silica and the water-soluble polymer; a diluent supplier capable of supplying a diluent containing an aggregation preventing agent to dilute the slurry; a mixer capable of receiving the slurry and the diluent having been supplied from the slurry supplier and the diluent supplier, respectively, the mixer forming a diluted slurry with a pH value of at least 9; and an ultrasonic vibrator capable of applying an ultrasonic vibration to the diluted slurry staying in the mixer or being fed out from the mixer. Here, the diluent supplying apparatus can change a dilution proportion of the diluted slurry.

A method of making an anti-reflection coating using a sol-gel process, for use in a photovoltaic device or the like. The method may include the following steps in certain example embodiments: forming a polymeric component of silica by mixing glycycloxypropyltrimethoxysilane (or other suitable silane) with one or more of a first solvent, a catalyst, and water; forming a silica sol gel by mixing the polymeric component with a colloidal silica, optionally a second solvent, and at least one organic additive; casting the mixture by spin coating to form a porous silica based layer on a substrate; and curing and/or heat treating the layer. This layer may make up all or only part of an anti-reflection coating.

A welding flux that includes a flux agent, water glass and colloidal compound formed from small particles of silicon dioxide. The welding flux has a very low hygroscopicity, thus is well suited from low hydrogen electrodes.

A process for producing a hydrophobic silica powder, comprises the steps for hydrophobic treatment of: adding to an aqueous silica sol containing hydrophilic colloidal silica having a specific surface area of 5.5 to 550 m²/g, a disilazane compound represented by formula (1)

(R¹₃Si)₂NH  (1)

wherein each R¹ is C_1-6alkyl group or phenyl group that is selected independently of one another, in an amount of 0.1 to 10 mmol per surface area 100 m² of the hydrophilic colloidal silica, to obtain a first mixture of the aqueous silica sol and the disilazane compound; and heating the mixture at a temperature of 50 to 100° C. for aging it to obtain a slurry as dispersion of hydrophobic treated colloidal silica. The process provides a hydrophobic silica powder through a simple hydrophobic treatment step.

The invention provides a cerium oxide polishing liquid suitable for polishing rock crystals, photomask quartz glass, semiconductor devices and glass-prepared hard disks and polishing low-dielectric-constant materials for interlayer insulating films of semiconductor devices of siloxane and the like. The polishing liquid contains surface modified nano cerium oxide, silicon dioxide, a dispersing agent, an oxidizing agent, an alkaline compound, an alcohol compound and water. Preferably, stearic acid treated nano cerium oxide is selected, the particle size is preferably 10-100 nm, and the mass content is 1-10%; preferably, the particle size of the colloidal silicon dioxide is 40-100 nm, and the mass content is 0.1-5%; preferably, the polishing liquid contains 0.01-5% of the high-molecular dispersing agent, 1-10% of the hydrogen peroxide oxidizing agent, and the balance an alcohol-water mixture, wherein the pH value of a slurry is 8-10. The nano cerium oxide polishing liquid selects the surface modified nano cerium oxide, has addition of a proper amount of the silicon dioxide, thereby reducing the grinding trigger time and improving the processing stability.

It is an object of the present invention to provide a laminate having excellent weatherability and abrasion resistance as well as adhesion.

The present invention relates to a laminate comprising a base, a first layer formed by thermally curing an acrylic resin composition and a second layer formed by thermally curing an organosiloxane resin composition, all of which are formed in the mentioned order, wherein

• • the acrylic resin composition comprises:
  • (A) an acrylic copolymer which contains at least 70 mol % of a recurring unit represented by the following formula (A):

wherein X is a hydrogen atom or methyl group, and Y is a methyl group, ethyl group, cycloalkyl group, hydroxyalkyl group having 2 to 5 carbon atoms or triazine-based ultraviolet absorber residue;

• • (B) a blocked polyisocyanate compound;
  • (C) a curing catalyst; and
  • (D) a triazine-based ultraviolet absorber, and
  • the organosiloxane resin composition comprises:
  • (E) colloidal silica and (F) a hydrolysis condensate of an alkoxysilane.

A chemical mechanical polishing aqueous dispersion includes (A) colloidal silica having an average particle size calculated from the specific surface area determined by the BET method of 10 to 60 nm, (B) an organic acid having two or more carboxyl groups and one or more hydroxyl groups in one molecule, and (C) a quaternary ammonium compound shown by the following general formula (1),

wherein R₁ to R₄ individually represent hydrocarbon groups, and M⁻ represents an anion, the chemical mechanical polishing aqueous dispersion having a pH of 3 to 5.

Colloidal silica having an increased particle size and narrow particle size distribution is disclosed. A method for continuously producing the desired colloidal composition is disclosed comprising the steps of providing preformed silica particles having a surface area which controls the particle size of the colloidal silica product, adding a feed silica comprising an alkaline solution and silicate at a feed rate which is less than a nucleation rate, and increasing the feed rate as the feed silica is added wherein the feed rate is less than the nucleation rate.

Disclosed is a high energy ray-curable composition which is excellent in storage stability before curing and enables to form a cured coating film which is excellent in hardness, property of preventing adhesion of fats and oils, property of wiping off fats and oils, abrasion resistance, transparency, water repellency, adhesion, smoothness and uniformity. Specifically disclosed is a high energy ray-curable composition containing the following components (A)-(D). (A) 100 parts by weight of a polyfunctional acrylate (B) 1-30 parts by weight of an organoalkoxysilane having an aliphatic unsaturated bond (C) 1-100 parts by weight of colloidal silica (D) 0.2-20 parts by weight of a fluorine compound having an aliphatic unsaturated bond.

The invention relates to low temperature curable spin-on glass materials which are useful for electronic applications, such as optical devices, in particular for flat panel displays. A substantially crack-free silicon polymer film is produced by (a) preparing a composition comprising at least one silicon containing pre-polymer, colloidal silica, an optional catalyst, and optional water; (b) coating a substrate with the composition to form a film on the substrate, (c) crosslinking the composition by heating to produce a substantially crack-free silicon polymer film, having a thickness of from about 700 Å to about 20,000 Å, and a transparency to light in the range of about 400 nm to about 800 nm of about 90% or more.

This invention provides a storage-stable dosage form of a thyroxine active drug composition which exhibits an improved stability. The formulation contains a thyroxine active drug substance, an alditol, and a saccharide, and, optionally, additional pharmaceutically accepted excipients. Levothyroxine sodium is the preferred active drug substance, mannitol is the preferred alditol, and sucrose is the preferred saccharide. Additional preferred excipients include, for example, microcrystalline cellulose, crospovidone, magnesium stearate, colloidal silicon dioxide, and sodium lauryl sulfate.

To give high mechanical strength, particularly compression strength, and excellent operationality in a two-paste system, a dental paste glass ionomer cement composition comprises a first paste comprising an α-β unsaturated carboxylic acid polymer, a filler that is not reacted with the α-β unsaturated carboxylic acid polymer and is not in a monodisperse state in water, a silica aqueous sol containing colloidal silica having an average particle diameter of 1 to 100 nm dispersed in a monodisperse state in water to an SiO₂ concentration of 1 to 50% by weight, and water, in prescribed amounts respectively, and a second paste containing fluoroalumino silicate glass powder in a prescribed amount, where the second paste sometimes contains a thickening agent comprising a water soluble polymer material and water, or a polymerizable monomer having no acid group.

An ink jet recording element comprising a support having thereon the following layers: a) a cationic mordant for an anionic dye; b) a nonionic or amphoteric material compatible with a) and c); c) colloidal silica; and d) a hydrophilic overcoat in an amount of at least about 0.25 g/m2; wherein either a) or c) can be directly on the support, b) is always between a) and c), and d) is the outermost layer.

A composition for chemical mechanical polishing a surface of a substrate having a plurality of ultra high purity sol gel processed colloidal silica particles for chemical mechanical polishing having alkali metals Li, Na, K, Rb, Cs, Fr and a combination thereof, at a total alkali concentration of about 300 ppb or less, with the proviso that the concentration of Na, if present, is less than 200 ppb; and a medium for suspending the particles is provided. Also, provided are methods of chemical mechanical polishing which included a step of contacting a substrate and a composition according to the present invention. The contacting is carried out at a temperature and for a period of time sufficient to planarize the substrate.

A method of recycling an abrasive slurry for recycling a slurry that: contains colloidal silica; and has been used in polishing semiconductor wafer(s) is provided. The method includes: adding a dispersant to the used slurry having been collected so as to prevent the used slurry from being gelled; irradiating ultrasound to the used slurry having been added with the dispersant so as to disperse a gelled portion and aggregated silica in the used slurry; and, by using a filter, removing a foreign substance contained in the used slurry having been irradiated with the ultrasound.

This invention provides a storage-stable dosage form of a thyroxine active drug composition which exhibits an improved stability. The formulation contains a thyroxine active drug substance and an antioxidant, and, optionally, additional pharmaceutically accepted excipients. Levothyroxine sodium is the preferred active drug substance, butylated hydroxyanisole is the preferred antioxidant. Additional preferred excipients include, for example, microcrystalline cellulose, sucrose, mannitol, crospovidone, magnesium stearate, colloidal silicon dioxide, and sodium lauryl sulfate.