Kyocera Corporation

Hirofumi Toda

Nobuyoshi Fujikawa

Shinji Isoyama

Kouichi Maruta

Shinjiro Shimo

A dielectric ceramic composition comprising main components represented by a composition formula on the weight basis, aMgO.multidot.bCaO.multidot.cTiO.sub.2, wherein a, b and c satisfy the following relationships, 25.ltoreq.a.ltoreq.35, 0.3.ltoreq.b.ltoreq.7, 60.ltoreq.c.ltoreq.70, a+b+c=100, blended with a boron-containing compound in an amount of from 3 to 20 parts by weight reckoned as B.sub.2 O.sub.3 and an alkali metal-containing compound in an amount of from 1 to 12 parts by weight reckoned as the alkali metal carbonate per 100 parts by weight of the main components, as well as a multilayer resonator made of said composition, and a filter using said resonator. The ceramic composition can be fired together with a conductor metal such as Ag or Cu at a relatively low temperature of 900.degree. to 1050.degree. C., exhibits large dielectric constant and Q-value, and a relatively small temperature coefficient .tau.f, lending itself well for use as a material for high-frequency electronic parts. The resonator made of this ceramic composition exhibits excellent tproperties in high-frequency regions, and can be realized in a small size.

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Hirofumi Toda