Abstract: A non-reducible dielectric ceramic composition consists essentially of a main component consisting essentially of oxides of BaO, CaO, MgO, TiO.sub.2, ZrO.sub.2 and Nb.sub.2 O.sub.5 and having a composition expressd by the general formula:{(Ba.sub.1-x-y Ca.sub.x Mg.sub.y)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2wherein 0<x.ltoreq.0.20, 0<y.ltoreq.0.05, 0<o.ltoreq.0.25, 0.0005.ltoreq.p .ltoreq.0.023, and 1.000.ltoreq.m.ltoreq.1.03; at least one primary additive selected from the group consisting of oxides of Mn, Fe, Cr, Co and Ni; and at least one secondary additive selected from the group consisting of SiO.sub.2 and ZnO. The primary additives contained in an mount of 0.02 to 2.0 moles per 100 moles of the main component in terms of respective oxides, MnO.sub.2, Fe.sub.2 O.sub.3, Cr.sub.2 O.sub.3, CoO and NiO, while the secondary additive is contained in an amount of 0.1 to 2.0 moles per 100 moles of the main component.

Abstract: A nonreducing dielectric ceramic composition that includes BaTi0.sub.3 as a main component, the BaTi0.sub.3 containing alkali metal oxides in an amount more than 0.04 weight % as impurities. One or more of the following rare earth metal oxides (Re.sub.2 O.sub.3): Tb.sub.2 O.sub.3, Dy.sub.2 O.sub.3, Ho.sub.2 O.sub.3 and Er.sub.2 O.sub.3 ; and Co.sub.2 O.sub.3 in the following ratios: BaTiO.sub.3 is 92.0-00.4 mol %; Re.sub.2 O.sub.3 is 0.3-4.0 mol %; and Co.sub.2 O.sub.3 is 0.3-4.0 mol %; the composition also includes the following subcomponents: 0.2-4.0 mol % BaO; 0.2-3.0 mol % of MnO; and 0.5-5.0 mol % of MgO. The composition may include 0.5-2.5 weight parts of oxide glass containing BaO-SrO-Li.sub.2 O-SiO.sub.2 incorporated with 100 weight parts for the above composition. The composition may also include 0.5-4.0 mol % CaTiO.sub.3, 0.5-3.5 mol % CaZrO.sub.3 or one or both of NiO and Al.sub.2 O.sub.3 in an amount 0.3-3.0 mol %. Further, 0.5-2.5 weight parts of oxide glass containing BaO-SrO-Li.sub.2 O-SiO.sub.

Abstract: The present invention is directed to non-reducible dielectric composition consisting essentially of a main composition composed of a modified barium titanate system and additives (A) and (B) incorporated therein, said main composition consisting essentially of oxides of Ba, Ca, Ti, Zr, and Nb and having a composition represented by general formula:{(Ba.sub.1-x Ca.sub.x)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2'wherein x, o, p and m satisfy the relationships of, ##EQU1## said additive (A) being composed at least one oxides selected from the group consisting of oxides of Mn, Fe, Cr, Co, and Ni, said additive (A) being incorporated into said main composition in an amount of 0.02 to 2.0 moles per 100 moles of said main composition in terms of respective oxides, MnO.sub.2, FeO.sub.3, Cr.sub.2 O.sub.3, CoO, and NiO, said additive (B) consisting of SiO.sub.2 and/or ZnO and incorporated into said main composition in an amount of 0.1 to 2.0 moles per 100 moles of said main composition.

Abstract: A non-reducible dielectric ceramic composition comprises of a basic composition expressed by the general formula:{(Ba.sub.1-x-y Sr.sub.x Ca.sub.y)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2wherein 0.05.ltoreq.x 0.30, 0.005.ltoreq.y.ltoreq.0.12, 0.ltoreq.o.ltoreq.0.20, 0.0005.ltoreq.p.ltoreq.0.012, and 1.002.ltoreq.m.ltoreq.1.03, or{(Ba.sub.1-x-y-z Sr.sub.x Ca.sub.y Mg.sub.z)O}.sub.m (Ti.sub.1-o-p Zr.sub.o Nb.sub.p)O.sub.2+p/2wherein 0.05.ltoreq.x.ltoreq.0.35, 0.005.ltoreq.y 0.12, 0.0005 .ltoreq.z.ltoreq.0.05, 0<o.ltoreq.0.20, 0.0005.ltoreq.p.ltoreq.0.02, 1.000.ltoreq.m.ltoreq.1.04. The composition contains an additive (A) composed of one or more oxides selected from the group of MnO.sub.2, Fe.sub.2 O.sub.3, Cr.sub.2 O.sub.3, CoO and NiO in an amount of 0.02 to 2.0 moles per 100 moles of the basic composition. The composition further contains an additive (B) consisting of SiO.sub.2 and/or ZnO in an amount of 0.1 to 2.

Abstract: A process for preparing a particulate ceramic material comprising the steps of:(a) adding carbon dioxide or an aqueous solution of a soluble carbonate to first aqueous solution of a nitrate or chloride of Ba, Sr, Ca or Mg in a first vessel to adjust the pH of said first aqueous solution to between 7 and 10 thereby forming a carbonate precipitate;(b) adding an aqueous solution of a soluble hydroxide to a second aqueous solution of a nitrate or chloride of Ti, Zr, Sn or Pb in a second vessel to adjust the pH of said second aqueous solution to between 7 and 10 thereby forming a hydroxide precipitate;(c) combining slurries containing the precipitates formed in said first and second vessels;(d) mixing the combined slurries;(e) passing the slurries through a filter;(f) washing the filter cake with water;(g) drying the filter cake to form a powder;(h) calcining the dried powder; and(i) grinding the calcined powder.

Abstract: Ceramic dielectric compositions for temperature compensating capacitors, exhibiting a high dielectric constant, a relatively small temperature coefficient of dielectric constant and a very excellent linearity of the temperature coefficient, comprising 1.2-19.0% by weight of SrO, 12.2-17.4% by weight of CaO, 35.8-43.9% by weight of TiO.sub.2, 15.7-37.6% by weight of Bi.sub.2 O.sub.3, 1.9-14.6% by weight of Pb.sub.3 O.sub.4 and 0.9-2.7% by weight of MgO.

Abstract: A ceramic dielectric composition of a ternary system Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 -Pb(Zn.sub.1/3 Nb.sub.2/3)O.sub.3 -PbTiO.sub.3, comprising 69.05-69.60% by weight of Pb.sub.3 O.sub.4, 2.41-4.00% by weight of MgO, 0.08-3.15% by weight of ZnO, 24.01-26.66% by weight of Nb.sub.2 O.sub.5 and 0.13-2.59% by weight of TiO.sub.2. The composition can be sintered at a low firing temperature less than 1,150.degree. C., and has a high dielectric constant above 10,000.