SINTERED BODY FOR CATHODE AND ITS MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To obtain a discharge tube in which sputtering rate is reduced and noise at the light-emitting operation can be suppressed as much as possible, and sufficient luminous amount is secured, and dark spot or the like hardly occurs, and which has a long life including durability. SOLUTION: A press molding of a prescribed shape which a mixture, wherein a metal powder for sintered material of either or both of tantalum and niobium and zirconium, and stearic acid of an additive as a sliding agent and a pore- forming agent are mixed, is compressed, is heated at approximately 600°C in the nitrogen atmosphere, and, by evaporating the additive, many pores are formed inside. This press molding is sintered in the vacuum sintering furnace at the maximum 1800°C or about for several hours by gradually increasing the temperature, and the sintered body is formed. As an active material, cesium chromate or cesium niobate is impregnated in this sintered body. COPYRIGHT: (C)2003,JPO