Patent ID: 8357311

Claim:
A polishing liquid composition comprising: composite oxide particles containing cerium and zirconium; a dispersing agent; and an aqueous medium, wherein a powder X-ray diffraction spectrum of the composite oxide particles obtained by CuKα1 ray, where λ=0.154050 nm, irradiation includes a first peak having a peak top in a diffraction angle 2θ range of 28.61 to 29.67°, wherein θ is a Bragg angle, a second peak having a peak top in a diffraction angle 2θ range of 33.14 to 34.53°, a third peak having a peak top in a diffraction angle 2θ range of 47.57 to 49.63°, and a fourth peak having a peak top in a diffraction angle 2θ range of 56.45 to 58.91°, wherein a half-width of the first peak is 0.8° or less, and wherein when there is at least one peak of a peak a 1 derived from a cerium oxide and a peak a 2 derived from a zirconium oxide in the powder X-ray diffraction spectrum, both heights of peak tops of the peaks a 1 , a 2 are 0% of a height of the peak top of the first peak, where the peak top of the peak a 1 lies in a diffraction angle 2θ range of 28.40 to 28.59° and the peak top of the peak a 2 lies in a diffraction angle 2θ range of 29.69 to 31.60°.