| 摘要 |
PROBLEM TO BE SOLVED: To provide dielectric ceramics which are obtained by firing in a reducing atmosphere, are high in a dielectric constant, lessen the temperature change of the dielectric constant and the change of the dielectric constant with time under a DC voltage loading, are high in the CR-product, are long in the accelerated life of the insulation resistance at a high temperature and under a high voltage and are excellent in reliability. SOLUTION: The dielectric ceramics containing an essential component expressed by ABO3 (A is Ba, etc., and B is Ti, etc.), and additive components including rear earth elements is so formed as to satisfy the conditions under which the ratio of the crystal particles to allow the average concentration of the rear earth elements at analysis points 1 to 9 within crystal particles 11 to attain <=1/2 the average concentration of the rear earth elements at a grain boundary 12 and to allow the concentration of the rear earth elements at an analysis point 1 in the central part of the crystal grains 11 to attain >=1/50 the maximum concentration of the rear earth elements at analysis points 6 to 9 of the region from the surface to 5% of the diameter of the crystal particles is 20 to 70%. |
