| abstract |
Having a sintering step of sintering a raw material of? -Sialon mixed with at least one of silicon nitride, aluminum nitride, aluminum oxide or silicon oxide and an optically active element compound at a temperature of 1820 占 폚 to 2200 占 폚 There is provided a method for producing an alumina comprising the steps of arranging a plurality of boron nitride containers in a graphite box so that a material of a sialon filled with a plurality of boron nitride containers in a sintering process is easily contacted with nitrogen gas, By firing in a nitrogen atmosphere, the carbon content is reduced, and novel? -Sialon having high emission intensity is obtained. |