Ceramic dielectric materials for microwave use and a method for producing thereof

Claim 1

A ceramic dielectric material formed primarily of a composite of two component materials X and Y of the general formula X l-A Y A , the first of said two component materials being of the general formula: X={BaO}.sub.x {TiO.sub.2 }.sub.y {(Sm.sub.2 O.sub.3).sub.l-m-n (SrO•CeO.sub.2).sub.m (CaO•CeO.sub.2).sub.n }.sub.z ; and the second of said two component materials being of the general formula: Y=SrTiO.sub.3 ; wherein, 0.1≦x≦0.25, 0.6≦y≦0.85, 0.05≦z≦0.3, 0≦m≦0.80, 0≦n<0.8,x+y+z=1, m+n≦0.8, 0<A≦0.40; and x, y, z, m, n, and A are expressed by mol fraction.

Claim 3

A method for producing a composite ceramic dielectric material comprising the steps: (a) selecting starting materials from the group consisting of BaCO 3 , TiO 2 , Sm 2 O 3 , CaCO 3 , SrCO 3 , CeO 2 , Mn 2 O 3 , SrTiO 3 , for preparation as a composite material of two component materials X and Y in the general formula X A Y l-A , the first of said two component materials being of the general formula: X={BaO}.sub.x {TiO.sub.2 }.sub.y {(Sm.sub.2 O.sub.3).sub.l-m-n (SrO•CeO.sub.2).sub.m (CaO•CeO.sub.2).sub.n }.sub.z ; and the second of said two component materials being of the general formula: Y=SrTiO.sub.3 ; wherein, 0.1≦x≦0.25, 0.6≦y≦0.85, 0.05≦z≦0.3, 0≦m≦0.80, 0≦n<0.8, x+y+z=1, m+n≦0.8, 0<A≦0.40; and x, y, z, m, n, and A are expressed by mol fraction; (b) weighing, compounding and mixing said selected starting materials of said first component material in proportions in accordance with said general formula for said first component material; (c) calcinating said mixed materials; (d) grinding said calcinated materials; (e) mixing said second component material SrTiO 3 in said calcinated and ground materials in proportions in accordance with the general formula X l-A Y A ; (f) molding said mixed first and second component materials by applying pressure thereto to form a molded body; and (g) holding the molded body so formed in an oxygen atmosphere at an elevated temperature for obtaining the composite ceramic dielectric material.

Claim 4

A method for producing a composite ceramic dielectric material comprising the steps: (a) selecting starting materials from the group consisting of BaCO 3 , TiO 2 , Sm 2 O 3 , CaCO 3 , SrCO 3 , CeO 2 , Mn 2 O 3 , SrTiO 3 , for preparation as a composite material of two component materials X and Y in the general formula X A Y l-A , the first of said two component materials being of the general formula: X={BaO}.sub.x {TiO.sub.2 }.sub.y {(Sm.sub.2 O.sub.3).sub.l-m-n (SrO•CeO.sub.2).sub.m (CaO•CeO.sub.2).sub.n }.sub.z ; and the second of said two component materials being of the general formula: Y=SrTiO.sub.3 ; wherein, 0.1≦x≦0.25, 0.6≦y≦0.85, 0.05≦z≦0.3, 0≦m≦0.80, 0≦n<0.8, x+y+z=1, m+n≦0.8, 0<A≦0.40; and x, y, z, m, n, and A are expressed by mol fraction; (b) weighing, compounding and mixing said selected starting materials of said first component material in proportions in accordance with said general formula for said first component material; (c) calcinating said mixed materials; (d) grinding said calcinated materials; (e) mixing said second component material SrTiO 3 in said calcinated and ground materials in proportions in accordance with the general formula X l-A Y A ; (f) molding said mixed first and second component materials by applying pressure thereto to form a molded body; and (g) holding the molded body so formed in an oxygen atmosphere at an elevated temperature for obtaining the composite ceramic dielectric material.