Abstract: There is provided a cerium-based abrasive containing cerium oxide as a main component, in which the abrasive particles composing the abrasive are coated with a coating layer containing at least either one of a silicon component of silicon or a silicon compound and an aluminum component of aluminum or an aluminum compound. The cerium-based abrasive can be produced by wet-dispersing the cerium-based abrasive in a dispersion medium to obtain a slurry and carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry. Further, the cerium-based abrasive can be produced by carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry during the pulverization step or after the pulverization step in the conventional cerium-based abrasive production process and after that roasting and classifying the obtained cerium-based abrasive.

Abstract: There is provided a cerium-based abrasive containing cerium oxide as a main component, in which the abrasive particles composing the abrasive are coated with a coating layer containing at least either one of a silicon component of silicon or a silicon compound and an aluminum component of aluminum or an aluminum compound. The cerium-based abrasive can be produced by wet-dispersing the cerium-based abrasive in a dispersion medium to obtain a slurry and carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry. Further, the cerium-based abrasive can be produced by carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry during the pulverization step or after the pulverization step in the conventional cerium-based abrasive production process and after that roasting and classifying the obtained cerium-based abrasive.

Abstract: There is provided a cerium-based abrasive containing cerium oxide as a main component, in which the abrasive particles composing the abrasive are coated with a coating layer containing at least either one of a silicon component of silicon or a silicon compound and an aluminum component of aluminum or an aluminum compound. The cerium-based abrasive can be produced by wet-dispersing the cerium-based abrasive in a dispersion medium to obtain a slurry and carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry. Further, the cerium-based abrasive can be produced by carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry during the pulverization step or after the pulverization step in the conventional cerium-based abrasive production process and after that roasting and classifying the obtained cerium-based abrasive.

Abstract: This invention aims to provide a method of manufacturing a cerium-based abrasive containing coarse particles in lower concentration and having higher polishing ability and excellent cleanability for a polished face. Further, the present invention provides a method of manufacturing a cerium-based abrasive, including the steps of pulverizing a raw material, roasting a raw material after pulverization and disintegrating a raw material after roasting, in which a cerium-based rare earth carbonate or a mixture of a cerium-based rare earth carbonate and a cerium-based rare earth oxide is used as a cerium-based abrasive raw material, and the step of pulverizing a raw material pulverizes a raw material through heating while the material is kept immersed in aqueous solution.

Abstract: This invention is a method for producing a cerium-based abrasive which includes: a step of grinding raw material for the cerium-based abrasive; a step of roasting the ground raw material; and a step of subjecting the roasted raw material to wet processing, the method being characterized in that it further includes a lower-temperature re-roasting step of heating the wet-processed raw material at 200 to 700° C. In the invention disclosed in this application, an abrasive with particularly preferable properties can be produced by fully drying the wet-processed raw material in a drying step, and subsequently subjecting the dried raw material to the lower-temperature re-roasting step.

Abstract: A cerium-based abrasive and a production method of the cerium-based abrasive excellent in polishing properties of a high polishing speed and scarce formation of polishing scratches are provided by keeping the color of the abrasive in specified ranges or stably making fluorine be contained in the abrasive. For example, as such a cerium-based abrasive, examples include a cerium-based abrasive containing cerium oxide as a main component and having an L* value in a range not lower than 65 and or lower 90, an a* value in a range 0 or higher but 15 or lower, and a b* value in a range 10 or higher but 30 or lower in the case the color is expressed by an L*a*b* color system.

Abstract: This invention aims to provide a method of manufacturing a cerium-based abrasive containing coarse particles in lower concentration and having higher polishing ability and excellent cleanability for a polished face. Further, the present invention provides a method of manufacturing a cerium-based abrasive, including the steps of pulverizing a raw material, roasting a raw material after pulverization and disintegrating a raw material after roasting, in which a cerium-based rare earth carbonate or a mixture of a cerium-based rare earth carbonate and a cerium-based rare earth oxide is used as a cerium-based abrasive raw material, and the step of pulverizing a raw material pulverizes a raw material through heating while the material is kept immersed in aqueous solution.

Abstract: This invention is a method for producing a cerium-based abrasive which includes: a step of grinding raw material for the cerium-based abrasive; a step of roasting the ground raw material; and a step of subjecting the roasted raw material to wet processing, the method being characterized in that it further includes a lower-temperature re-roasting step of heating the wet-processed raw material at 200 to 700° C. In the invention disclosed in this application, an abrasive with particularly preferable properties can be produced by fully drying the wet-processed raw material in a drying step, and subsequently subjecting the dried raw material to the lower-temperature re-roasting step.

Abstract: There is provided a cerium-based abrasive containing cerium oxide as a main component, in which the abrasive particles composing the abrasive are coated with a coating layer containing at least either one of a silicon component of silicon or a silicon compound and an aluminum component of aluminum or an aluminum compound. The cerium-based abrasive can be produced by wet-dispersing the cerium-based abrasive in a dispersion medium to obtain a slurry and carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry. Further, the cerium-based abrasive can be produced by carrying out surface treatment by adding a treatment solution containing at least either one of the silicon compound and the aluminum compound to the slurry during the pulverization step or after the pulverization step in the conventional cerium-based abrasive production process and after that roasting and classifying the obtained cerium-based abrasive.

Abstract: A cerium-based abrasive and a production method of the cerium-based abrasive excellent in polishing properties of a high polishing speed and scarce formation of polishing scratches are provided by keeping the color of the abrasive in specified ranges or stably making fluorine be contained in the abrasive. For example, as such a cerium-based abrasive, examples include a cerium-based abrasive containing cerium oxide as a main component and having an L* value in a range not lower than 65 and or lower 90, an a* value in a range 0 or higher but 15 or lower, and a b* value in a range 10 or higher but 30 or lower in the case the color is expressed by an L*a*b* color system.

Abstract: Regarding a cerium oxide-based abrasive containing cerium oxide as a main component and abrasive particles with an average particle diameter of 0.2 to 3.0 &mgr;m, the present invention provides a cerium-based abrasive containing coarse particles of 10 &mgr;m or larger in a concentration of 1000 ppm or lower (by weight) or magnetic particles in a concentration of 1000 ppm or lower (by weight). The coarse particles or the magnetic particles are particularly preferable to exist in a concentration of 300 ppm or lower (by weight). Further, by controlling an average value of the specific surface area of the abrasive particles to be within 0.5 to 30 m2/g, the resulting abrasive is provided with a high cutting property and is capable of forming a polished face with high precision. The production method of such cerium-based abrasives comprises control being the concentration of the coarse particles and the classification point and repeated classification.

Abstract: The present invention provides a stock material for cerium-based abrasives which can be sintered at a relatively low roasting temperature without causing abnormal growth of the particles. More concretely, the stock material for cerium-based abrasives is produced by calcinating the carbonate of rare earth at a given temperature level to partly convert it into the oxide of rare earth in such a way to produce the mixed stock material having a loss on ignition of 0.5 to 25% on a dry basis, determined by heating at 1000° C. for 1 hour.

Abstract: Regarding a cerium oxide-based abrasive containing cerium oxide as a main component and abrasive particles with an average particle diameter of 0.2 to 3.0 &mgr;m, the present invention provides a cerium-based abrasive containing coarse particles of 10 &mgr;m or larger in a concentration of 1000 ppm or lower (by weight) or magnetic particles in a concentration of 1000 ppm or lower (by weight). The coarse particles or the magnetic particles are particularly preferable to exist in a concentration of 300 ppm or lower (by weight) . Further, by controlling an average value of the specific surface area of the abrasive particles to be within 0.5 to 30 m2/g, the resulting abrasive is provided with a high cutting property and is capable of forming a polished face with high precision. The production method of such cerium-based abrasives comprises control being the concentration of the coarse particles and the classification point and repeated classification.