Abstract: The present invention relates to the dielectric composition including barium titanate, strontium titanate, titanium oxide and bismuth oxide. In case when the content of barium titanate, converted to BaTiO3, is a mol %, the content of strontium titanate, converted to SrTiO3, is b mol %, the content of titanium oxide and bismuth oxide, converted to Bi2Ti3O9, is c mol %, and a+b+c=100, a, b and c are values within a scope surrounded by the following four points, i.e. point A, point B, point C and point D in a three-dimensional phase diagram. Point A: (a, b, c)=(52.1, 40.0, 7.9); point B: (a, b, c)=(86.5, 5.6, 7.9); point C: (a, b, c)=(91.0, 5.6, 3.4); point D: (a, b, c)=(56.6, 40.0, 3.4).

Abstract: A dielectric ceramic composition comprising forsterite in an amount of 93.0 to 99.0 mol % when calculating in terms of 2MgO.SiO2 and calcium titanate in an amount of 1.0 to 7.0 mol % when calculating in terms of CaTiO3 as main components, and as a subcomponent, aluminum oxide in an amount of 0.2 to 5 mass % when calculating in terms of Al2O3 per 100 mass % of said main components. According to the present invention, a dielectric ceramic composition, capable of having both low permittivity and good frequency-temperature characteristic as well as ensuring high Qf value and further having sufficient mechanical strength, and suitable to use in an antenna, a filter and the like used in the high-frequency region, can be provided. Also, the present invention allows providing a dielectric ceramic composition further having resistance to reduction in addition to all of the above properties.

Abstract: A dielectric ceramic composition comprising forsterite in an amount of 93.0 to 99.0 mol % when calculating in terms of 2MgO—SiO2 and calcium titanate in an amount of 1.0 to 7.0 mol % when calculating in terms of CaTiO3 as main components, and as a subcomponent, aluminum oxide in an amount of 0.2 to 5 mass % when calculating in terms of Al2O3 per 100 mass % of said main components. According to the present invention, a dielectric ceramic composition, capable of having both low permittivity and good frequency-temperature characteristic as well as ensuring high Qf value and further having sufficient mechanical strength, and suitable to use in an antenna, a filter and the like used in the high-frequency region, can be provided. Also, the present invention allows providing a dielectric ceramic composition further having resistance to reduction in addition to all of the above properties.