Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Murata Manufacturing Co., Ltd.

Kazuhiro Komatsu

Atsuo Nagai

Kenji Oka

Kazuki Hirata

Hiroki Moriwake

Hideki Kuramitsu

Keiji Kobayashi

Tadashi Onomi

A dielectric ceramic composition containing at least 0.15 to 2.5 mol of a Mg compound in terms of MgO, 0 to 1.6 mol of a Ba compound in terms of BaCO, 0.1 to 3.0 mol of a Ln (Ln includes two or three kinds of elements selected from Er, Dy, and Ho with Er being essential) compound in terms of LnO, 0.01 to 0.4 mol of a Mn compound in terms of MnO, 0.01 to 0.26 mol of a V compound in terms of VO, 0.3 to 3.5 mol of a Si compound in terms of SiO, and 0.01 to 2.5 mol of an Al compound in terms of AlOto 100 mol of barium titanate adjusted for a Ba/Ti molar ratio of 0.997 to 1.007.

Dielectric porcelain composition, and method for manufacturing capacitor using the same

A method of manufacturing a multilayer ceramic capacitor includes the steps of: preparing a mixture of a raw material powder mainly composed of barium titanate particles; forming the mixture and a binder into a green sheet; alternately layering the green sheet and an internal electrode to obtain a laminated body; and sintering the laminated body. The step of preparing the mixture includes the steps of: introducing the raw material powder and the dispersion medium into a mixing container, and stirring them with balls serving as a mixing medium, to obtain a slurry containing a raw material powder mixture; and drying the slurry. The mixing medium has a diameter that is equal to or less than 400 times the mean particle size of the barium titanate particles of the raw material. The present invention provides a multilayer ceramic capacitor having good DC bias characteristics by suppressing the variation in crystal particles.

Method for manufacturing multilayer ceramic capacitor

The present invention relates to a method of manufacturing a multilayer ceramic capacitor, having the steps of: (a) alternately layering internal electrodes and ceramic green sheets containing a ceramic material having barium titanate to form a laminated body; (b) sintering the laminated body to obtain a sintered body; and (c) forming an external electrode on end faces of the sintered body to obtain a multilayer ceramic capacitor. The barium titanate has a diffraction line derived from (002) plane and a diffraction line derived from (200) plane in an X-ray diffraction chart. The ratio I/Iof peak intensity Iat 2&#x3b8;to diffraction intensity Iat a midpoint angle between peak angle 2&#x3b8;of the diffraction line derived from the (002) plane and peak angle 2&#x3b8;of the diffraction line derived from the (200) plane is 2 to 10. The product r&#xb7;Sa of mean particle size r (&#x3bc;m) of the barium titanate and specific surface area Sa (m/g) is 1 to 2.

Process for producing laminated ceramic capacitor

In present invention, the c-axis/a-axis ratio is set in the range of 1.005 through 1.009 in a tetragonal-perovskite-type crystal structure of BaTiO. The present invention provides a ceramic capacitor having a large capacity and a method of manufacturing it.

Ceramic capacitor and method of manufacturing the same

A dielectric ceramic composition of the present invention is a mixture of barium titanate as a main component whose Ba/Ti molar ratio ranging from 1.001 to 1.05 and sub components comprising, at least 0.5 to 5.0 mol of Mg in the form of MgO, 0.1 to 3.0 mol of Dy in the form of Dy O , 0.01 to 0.4 mol of Mn in the form of Mn O , 0.01 to 0.26 mol of V in the form of V O , 0.3 to 3.5 mol of Si in the form of SiO and 0.01 to 3.0 mol of Al in the form of Al O per 100 mol of the barium titanate. Even when external electrodes are made of base metal such as copper or the like, a multilayer capacitor whose dielectric layers are not reduced and have high insulation resistance can be obtained by using the dielectric ceramic composition of the present invention.

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Chitose, Japan

Kazuhiro Komatsu