Banner, Birch, McKie and Beckett
Dielectric ceramic compositions
 The improved dielectric ceramic composition has sufficiently high dielectric constant, high insulation resistance and small dielectric loss to be suitable for use as a material for ceramic capacitors. The composition comprises as a main component a three-component ceramic composition in solid solution having the formula Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 -Pb(Ni.sub.1/3 Nb.sub.2/3)O.sub.3 -PbTiO.sub.3 which, when expressed by xPb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 -yPb(Ni.sub.1/3 Nb.sub.2/3)O.sub.3 -zPbTiO.sub.3, is defined by the area surrounded by the following points of (x, y, z), i.e., (0.70, 0.20, 0.10), (0.70, 0.15, 0.15), (0.83, 0.02, 0.15), (0.96, 0.02, 0.02) and (0.78, 0.20, 0.02), and this ceramic composition further contains a Mn oxide or a Mn-containing complex oxide as an additive. 
NEC Corporation
C H
C04B H01G
inventional inventional
Kazuaki Tetsuo Souichiro Atsushi Shinji Toru
Utsumi Yoshimoto Sugano Ochi Abe Mori