CERAMIC DIELECTRICS AND COMPOSITIONS THEREFOR

摘要

A composition for producing ceramic dielectrics which comprises: a mixture of barium titanate which has average particle size of 0.1-1.5 mu m is amounts of 98-60 mole % and a perovskite type barium titanate solid solution which has average particle size of 0.1-1.5 mu m and a Curie temperature of 50 DEG -115 DEG C. in amounts of 2-40 mole %; and (A) at least one of niobium oxides and tantalum oxides in amounts of 0.3-2 moles % in relation to 100 mole % of the mixture; and (B) at least one of cobalt oxides, nickel oxides, magnesium oxides, manganese oxides, copper oxides and oxides of a rare earth metal in amounts of 0.1-2 moles % in relation to 100 mole % of the mixture. The composition provides a ceramic dielectric which has a large relative permittivity and still has a small temperature dependence of relative permittivity within +/-15% over a temperature range between -55 DEG C. and +125 DEG C. taking a relative permittivity at 20 DEG C. as a standard.