| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high density, large-sized sintered compact under normal pressure through such processes that, stock powder prepared by specifying both reaction and calcination conditions using indium nitrate and tin nitrate as raw materials and also using an alkaline carbonate as neutralizing agent is subjected to each specific primary adjustment and secondary adjustment to produce granulated powder which is then molded and sintered. SOLUTION: First, an alkaline carbonate or bicarbonate is added at <=60 deg.C to an indium nitrate solution or its mixture with tin nitrate to effect neutralization, the resultant precipitate is dried and then calcinated in air or an oxygen- enriched atmosphere to produce indium oxide powder or the oxide-contg. Indium oxide powder. Secondary, the tin oxide-contg. indium oxide powder <=30ppm in halogen element content and >=15m<2> /g in specific surface area is subjected to primary adjustment so as to be <=1μm and <=3μm in D50 and D90 as respective laser scattering diameters and then subjected to secondary adjustment so as to be 30-80μm in average particle size and <=25 degree in angle of repose, Finally, the resultant granulated powder thus produced in subjected to pressure molding and then sintered in air to obtain the objective ITO sintered compact. |
