Abstract: A polishing composition includes more than 0.1% by mass of colloidal silica, and water, and has a pH of 6 or less. The polishing composition has the ability to polish a titanium material at a high stock removal rate. Thus, the polishing composition is suitable for use in applications for polishing a titanium-containing object.

Abstract: A polishing composition contains at least abrasive grains and water and is used in polishing an object to be polished. The abrasive grains are selected so as to satisfy the relationship X1×Y1?0 and the relationship X2×Y2>0, where X1 [mV] represents the zeta potential of the abrasive grains measured during polishing of the object by using the polishing composition, Y1 [mV] represents the zeta potential of the object measured during polishing of the object by using the polishing composition, X2 [mV] represents the zeta potential of the abrasive grains measured during washing of the object after polishing, and Y2 [mV] represents the zeta potential of the object measured during washing of the object after polishing. The abrasive grains are preferably of silicon oxide, aluminum oxide, cerium oxide, zirconium oxide, silicon carbide, or diamond. The object is preferably of a nickel-containing alloy, silicon oxide, or aluminum oxide.

Abstract: A polishing composition contains at least abrasive grains and water and is used in polishing an object to be polished formed of a substrate material for optical devices, a substrate material for power devices, or a compound semiconductor material. The abrasive grains have a zeta potential satisfying the relationship X×Y?0, where X [mV] represents the zeta potential of the abrasive grains measured in the polishing composition and Y [mV] represents the zeta potential of the object to be polished measured during polishing using the polishing composition. The abrasive grains are preferably of aluminum oxide, silicon oxide, zirconium oxide, diamond, or silicon carbide. The object to be polished is preferably of sapphire, gallium nitride, silicon carbide, gallium arsenide, indium arsenide, or indium phosphide.

Abstract: According to the present invention, a filtration method capable of prolonging the life of a filter and regenerating it without impairing the efficiency can be provided. Further, a filter regenerating method and a regenerating apparatus, for efficiently regenerating a filter, are provided. The filtration method of the present invention is a method of subjecting a liquid to filtration by using a resin media filter, wherein ultrasonic waves at a frequency of at least 30 kHz are applied to the filter while the filtration is carried out, during the temporary stop of the filtration or after completion of the filtration. Efficient purification is possible by subjecting a polishing composition to filtration by such a filtration method. Further, the filter regenerating method of the present invention comprises applying ultrasonic waves at a frequency of at least 30 kHz to a used resin filter.

Abstract: A polishing composition includes more than 0.1% by mass of colloidal silica, and water, and has a pH of 6 or less. The polishing composition has the ability to polish a titanium material at a high stock removal rate. Thus, the polishing composition is suitable for use in applications for polishing a titanium-containing object.

Abstract: A polishing composition includes an abrasive, phosphoric acid, and an oxidizing agent and has a pH of 6 or less. The polishing composition has the capability for polishing an alloy containing nickel and iron with a high stock removal rate. Accordingly, the polishing composition is preferably used in an application for polishing an object including the alloy containing nickel and iron.

Abstract: A polishing composition contains alumina, a complexing agent, and an oxidizing agent. It is preferable that the complexing agent is at least one compound selected from an ?-amino acid, ammonia, and an ammonium salt. The polishing composition is preferably used in applications for polishing an object having a resin section with a trench, and a conductor layer provided on the resin section so that at least the trench is filled with the conductor layer.

Abstract: A polishing composition capable of satisfactorily polishing a semiconductor. The first polishing composition of the present invention includes silicon dioxide, at least one component selected from periodic acids and salts thereof, at least one component selected from tetraalkyl ammonium hydroxides and tetraalkyl ammonium chlorides, hydrochloric acid, and water, and contains substantially no iron. The second polishing composition of the present invention includes a predetermined amount of fumed silica, a predetermined amount of at least one component selected from periodic acids and salts thereof, a tetraalkyl ammonium salt represented by the following general formula (1), at least one component selected from ethylene glycol and propylene glycol, and water. The pH of the second polishing composition is greater than or equal to 1.8 and is less than 4.0.

Abstract: A polishing composition includes an abrasive, phosphoric acid, and an oxidizing agent and has a pH of 6 or less. The polishing composition has the capability for polishing an alloy containing nickel and iron with a high stock removal rate. Accordingly, the polishing composition is preferably used in an application for polishing an object including the alloy containing nickel and iron.

Abstract: A polishing composition contains alumina, a complexing agent, and an oxidizing agent. It is preferable that the complexing agent is at least one compound selected from an ?-amino acid, ammonia, and an ammonium salt. The polishing composition is preferably used in applications for polishing an object having a resin section with a trench, and a conductor layer provided on the resin section so that at least the trench is filled with the conductor layer.

Abstract: A polishing composition includes more than 0.1% by mass of colloidal silica, and water, and has a pH of 6 or less. The polishing composition has the ability to polish a titanium material at a high stock removal rate. Thus, the polishing composition is suitable for use in applications for polishing a titanium-containing object.

Abstract: A polishing composition capable of satisfactorily polishing a semiconductor. The first polishing composition of the present invention includes silicon dioxide, at least one component selected from periodic acids and salts thereof, at least one component selected from tetraalkyl ammonium hydroxides and tetraalkyl ammonium chlorides, hydrochloric acid, and water, and contains substantially no iron. The second polishing composition of the present invention includes a predetermined amount of fumed silica, a predetermined amount of at least one component selected from periodic acids and salts thereof, a tetraalkyl ammonium salt represented by the following general formula (1), at least one component selected from ethylene glycol and propylene glycol, and water. The pH of the second polishing composition is greater than or equal to 1.8 and is less than 4.0.

Abstract: A polishing composition comprising: (a) at least one abrasive selected from the group consisting of silicon dioxide and aluminum oxide, (b) at least one organic compound selected from the group consisting of a polyethylene oxide, a polypropylene oxide, a polyoxyethylene alkyl ether, a polyoxypropylene alkyl ether, a polyoxyethylenepolyoxypropylene alkyl ether and a polyoxyalkylene addition polymer having a C≡C triple bond, represented by the formula (1): wherein each of R1 to R6 is H or a C1-10 alkyl group, each of X and Y is an ethyleneoxy group or a propyleneoxy group, and each of m and n is a positive number of from 1 to 20, (c) at least one polishing accelerating compound selected from the group consisting of citric acid, oxalic acid, tartaric acid, glycine, &agr;-alanine and histidine, (d) at least one anticorrosive selected from the group consisting of benzotriazole, benzimidazole, triazole, imidazole and tolyltriazole, (e) hydrogen peroxide, and (f) water.

Abstract: A polishing method for reliably polishing a polishing target and a polishing composition used for polishing are provided. The polishing method of the present invention includes a first step in which the polishing target is polished with a first polishing composition, a second step in which the polishing target is polished with a second polishing composition, and a third step in which polishing target is polished with a third polishing composition. The polishing target is a multilayer, which includes an insulation layer, which has trenches on its surface, a barrier layer located on the insulation layer, and a conductor layer located on the barrier layer. In the first step, part of a portion of the conductor layer located outside the trenches is removed. In the second step, a remaining part of the portion of the conductor layer located outside the trenches is removed. In the third step, a portion of the barrier layer located outside the trenches is removed.

Abstract: A polishing composition comprising:

Abstract: A process for producing a polishing composition, which comprises preliminarily adjusting water to pH 2-4, adding from 40 to 60 wt % of fumed silica to the water under high shearing force, adding water to lower the viscosity to 2-10000 cps, stirring the mixture under low shearing force for at least 5 minutes, adding water to lower the fumed silica concentration to 10-38 wt %, and adding a basic substance under vigorous stirring to raise the pH to 9-12.

Abstract: A polishing composition comprising fumed silica, a basic potassium compound and water, of which the specific electric conductivity is from 100 to 5,500 .mu.S/cm.