Murata Manufacturing Co., Ltd.

Kazuhiro Harada

Harunobu Sano

Shinichi Kobayashi

Osamu Yamaoka

Yoshitaka Kageyama

Toshiya Esumi

Sano Harunobu

A nonlinear dielectric ceramic having the D-E hysteresis characteristics contains a barium titanate-based compound as a principal constituent and a nonreducing oxide glass as a secondary constituent, and thus the nonlinear dielectric ceramic has reduction resistance. A pulse generating capacitor including the nonlinear dielectric ceramic, a high-pressure vapor discharge lamp circuit including the pulse generating capacitor, and a high-pressure vapor discharge lamp including the pulse generating capacitor are also disclosed.

Nonlinear dielectric ceramic, pulse generating capacitor, high-pressure vapor discharge lamp circuit, and high-pressure vapor discharge lamp

An inexpensive capacitor for pulse generation whose characteristics do not deteriorate even when the capacitor is used in a high temperature, high vacuum, reducing atmosphere, and which enables generation of high-voltage pulses over a wide temperature range. The dielectric body of the capacitor is constructed of a non-linear dielectric ceramic which exhibits resistance to reduction. The non-linear dielectric ceramic comprises a polycrystalline substance containing barium titanate as a primary component, and when the polycrystalline substance is represented by (1&minus;a&minus;b)ABO &plus;aM&plus;bR wherein ABO is a barium titanate component and represents a perovskite structure, M is an oxide of at least one element selected from the group consisting of Mn, Ni and Co, R is an oxide of at least one element selected from the group consisting of La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er and Yb, and a and b represent mole fractions; A, B, a, and b satisfy the following relationships: 1.000&lE;A/B&lE;1.006 (mole ratio), 0.3&lE;b/a&lE;3, 0.0015&lE;a&lE;0.0050, and 0.0015&lE;b&lE;0.0050, and a total content of M and R represented by Ad satisfies 0.3<Ad&lE;1.0 (wt. %).

Dielectric ceramic and a capacitor using the same

A dielectric ceramic composition including: a barium titanate containing principal component represented by the formula: (1-.alpha.-.beta.-.gamma.){BaO}.sub.m .multidot.TiO.sub.2 +.alpha.M.sub.2 O.sub.3 +.beta.Re.sub.2 O.sub.3 +.gamma.(Mn.sub.1-x-y Ni.sub.x Co.sub.y)O wherein M.sub.2 O.sub.3 is at least one of Sc.sub.2 O.sub.3 and Y.sub.2 O.sub.3 ; Re.sub.2 O.sub.3 is at least one of Sm.sub.2 O.sub.3, Eu.sub.2 O.sub.3, and Gd.sub.2 O.sub.3 ; 0.0025.ltoreq..alpha.+.beta..ltoreq.0.025, 0&lt;.beta..ltoreq.0.0075, 0.0025.ltoreq..gamma..ltoreq.0.05, .gamma./(.alpha.+.beta.).ltoreq.4, 0.ltoreq.x&lt;1.0, 0.ltoreq.y&lt;1.0, 0.ltoreq.x+y&lt;1.0, and 1.000&lt;m.ltoreq.1.035, at least one of scandium oxide and yttrium oxide, at least one of samarium oxide, europium oxide and gadolinium oxide, and at least one oxide of magnesium in an amount of from about 0.5 to 5.0 mols calculated as MgO to 100 mols of the principal components and further containing from about 0.2 to 3.0 parts by weight of an Al.sub.2 O.sub.3 --MO--B.sub.2 O.sub.3 oxide glass, wherein MO is at least one of BaO, CaO, SrO, MgO, ZnO, and MnO, to 100 parts by weight of the sum total of the principal components and magnesium oxide.

Monolithic ceramic capacitor

A multilayer ceramic capacitor is made of a principal component (100 mol) represented by the compositional formula

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Shiga-ken, Japan

Kazuhiro Harada