Patent ID: 8476340

Claim:
Ceramic powder having a multi-peak frequency distribution pattern having at least two peaks as a particle size distribution as determined using a laser diffraction-scattering type particle size-analyzer, the maximum particle size for the first peak ranging from 40 to 80 μm and that for the second peak ranging from 3 to 8 μm, the rate of the particles having a particle size of not less than 20 μm and less than 40 μm being not more than 20% by mass (inclusive of 0% by mass), the ceramic powder having a chemical absorption amount of ammonia ranging from 0.1 to 1.8 μmole/g the ceramic powder being silica powder having an Al 2 O 3 content ranging from 100 to 8,000 ppm, and the ceramic powder being produced by coating the surface of starting silica powder with alumina particles and then treating the coated powder with a flame to thus melt and sphere the coated powder.