Patent ID: 8323368
Filing Date: 2012-12-04
Classification: B82Y,C01G,C01P,C09K

Abstract:
1. A method of producing a polishing composition containing zirconium oxide sol, comprising: a first baking of a zirconium compound comprising zirconium compound particles having a d50 of 5 to 25 μm and a d99 of 60 μm or less, wherein the temperature is elevated from room temperature with a temperature elevating rate of 0.1 to 5° C./min until the temperature reaches a first baking temperature in the range of 200 to less than 400° C., a second baking of the zirconium compound, wherein the temperature is elevated from the first baking temperature with a temperature elevating rate of 0.1 to 10° C./min until the temperature reaches a second baking temperature in the range of 400 to 1000° C. to obtain a zirconium oxide powder, wherein the second baking is performed immediately after the temperature has reached the first baking temperature, or the second baking is performed after the temperature has been maintained at the first baking temperature for some time, up to about 100 hours; and wet-grinding the zirconium oxide powder in an aqueous medium until the d50 of zirconium oxide particles becomes 80 to 130 nm and the d99 of zirconium oxide particles becomes 150 to 500 nm, wherein the wet-grinding is performed by grinding the zirconium oxide powder in the aqueous medium by using stabilized zirconia grinding beads having a diameter of 0.1 to 3.0 mm in a volume ratio of (the zirconium oxide slurry):(the grinding beads) of 1:0.5 to 2.0 using a noncontinuous-type grinding apparatus; wherein: