Ceramic composition of high dielectric constant comprising PbO.sub.3, La.sub.2 O.sub.3, MO, ZrO.sub.2 and TiO.sub.2
 Disclosed herein is a ceramic composition of high dielectric constant which comprises the major constituents of PbO, La.sub.2 O.sub.3, MO, ZrO.sub.2, and TiO.sub.2 in the ratio defined by the formula below. EQU (1-x-y)PbO.multidot.x/2La.sub.2 O.sub.3 .multidot.yMo.multidot.(1-z)ZrO.sub.2 .multidot.zTiO.sub.2 where, PA1 M represents Ba and/or Sr; PA1 0.06.ltoreq.x.ltoreq.0.30 PA1 0.03.ltoreq.y.ltoreq.0.48 PA1 0.20.ltoreq.z.ltoreq.0.50 and an additive represented by PbWo.sub.4 and/or Pb(Mg.sub.1/2 W.sub.1/2)O.sub.3 in an amount of 1-40 wt % (in total) based on the above-mentioned major constituents (provided that the amount of PbWO.sub.4 is less than 15 wt % of the amount of the major constituents and the amount of Pb(Mg.sub.1/2 W.sub.1/2)O.sub.3 is less than 40 wt % of the amount of the major constituents). Less than 5 mol % of all Pb in the composition may be replaced by Ag and/or less than 6 mol % of all Pb in the composition may be replaced by Bi. 
Mitsubishi Mining and Cement Co., Ltd.
C H
C04B H01G
inventional inventional
Takashi Masashi Takeshi
Yamaguchi Saito Inoue