Ceramic dielectric and composition for the production thereof

摘要

The invention relates to a composition for producing ceramic dielectrics, which comprises: a mixture of barium titanate possessing an average particle size of 0.1-1.5 mu m in amounts of 98-60 mol % and a solid solution of barium titanate of the perovskite type possessing an average particle size of 0.1-1.5 mu m and a Curie temperature of 50-115@C in amounts of 2-40 mol %, and (A) at least one of the compounds niobium oxides and tantalum oxides in amounts of 0.3-2 mol %, based on 100 mol % of mixture, and (B)at least one of the compounds cobalt oxides, nickel oxides, magnesium oxides, manganese oxides, copper oxides and oxides of the rare earth metals in amounts of 0.1-2 mol %, based on 100 mol % of mixture. Such a composition gives ceramic dielectrics which have a high relative dielectric constant but a low temperature dependence of the relative dielectric constant within +/- 15 % over a temperature range between -55@C and +125@C, with the relative dielectric constant at 20@C being taken as standard.