Nippon Soken, Inc.

Denso Corporation

Other

Horiba, Ltd.

Atsuhiro Sumiya

Toshiatsu Nagaya

Hitoshi Shindo

Takashi Yamamoto

Eturo Yasuda

Akira Fujii

Itsuhei Ogata

Tsukasa Satake

Etsuro Yasuda

Juichiro Ukon

Takumi Kataoka

Noriaki Kihara

Yasunori Suzuki

Kumi Sawaguchi

Youta Iwamoto

Ryoji Kai

A method of producing a laminated dielectric element of high quality, free of delamination. A method of producing a laminated dielectric elementby alternately laminating dielectric ceramic layersand base metal electrode layerscomprising the steps of printing electrodes by applying a paste material for the base metal electrodes onto the surfaces of at least one side of the ceramic green sheets, laminating and press-adhering the ceramic green sheets to fabricate a laminate thereof, dewaxing the laminate, reducing the electrodes to form base metal electrode layers by heating the laminate while flowing an atmospheric gas and by reducing the paste material for the base metal electrodes, and sintering the laminate. In the step of reducing the electrodes, the paste material for the base metal electrodes is so reduced that the amount of the base metal oxide remaining in the base metal electrode layers is not larger than 20% by weight and that the amount of lead liberated from the ceramic material is not larger than 30 atomic % within 5000 &#x212b; from the surfaces of the base metal electrode layers.

Method for fabricating laminate-type dielectric element

This invention provides a method of producing a laminate type dielectric device free from peeling of an electrode layer and a ceramic layer and from voids in both electrode layer and ceramic layer, and an electrode paste material. The invention relates also to an electrode paste material for constituting electrode layers of a laminate type dielectric device produced by at least the steps of alternately laminating ceramic layerscontaining a lead element as a constituent component and electrode layers, and degreasing and baking the laminate, wherein the electrode paste material contains CuO as a principal component of a starting material of an electrically conductive material, a solvent, a binder, and a cooperative material consisting of at least one kind of the main components constituting the ceramic layer

Production method for laminate type dielectric device and electrode paste material

This invention provides a stacked ceramic body that prevents reaction between components of dielectric layers and components of electrode layers of an unsintered stacked body during sintering and in which both components do not easily form a liquid phase, and a production method of such a stacked ceramic body. A print portionis formed on a green sheetcontaining lead by use of an electrode paste consisting of copper oxide as its main component. A desired number of print sheetsare stacked to give an unsintered stacked body. Degreasing is conducted in an atmosphere to degrease organic components. The print portionis subjected to reducing treatment in a reducing atmosphere containing hydrogen and is converted to a print portioncontaining copper as its main component. The unsintered stacked bodyis sintered in a reducing atmosphere. Dielectric layers containing lead and electrode layers for applying a voltage to the dielectric layers are alternately stacked, and an oxidation portion containing copper is formed in the proximity of a surface of the electrode layer. A thickness of the oxidation portion in a stacking direction is 0.5 to 2 &#x3bc;m and a copper content in the oxidation portion is 1 to 30 wt %.

Stacked ceramic body and production method thereof

This invention provides a method for producing a stacked ceramic body that does not require strict control of an oxygen partial pressure in a sintering gas. To produce a stacked ceramic body by alternately stacking dielectric layer and electrode layers, an unsintered stacked bodyis prepared by alternately stacking unsintered dielectric layers containing a PZT type dielectric material and unsintered electrode layers containing an electrode material, and is sintered in a sintering gas to which a dielectric layer anti-reducing agentand an electrode layer anti-oxidantare introduced. Alternatively, sintering is conducted in a gas containing only the dielectric layer anti-reducing agentor in a gas containing only the electrode layer anti-oxidant

Method for producing stacked ceramic body

A laminate type dielectric device is formed by alternately laminating dielectric ceramic layers and electrode layers and integrally baking the laminate product. The electode layers are mainly made of an electrically conductive base metal material having greater standard Gibbs free energy for the formation of a metal oxide at a baking temperature than that of the ceramic material constituting the dielectric ceramic layers. Segregation of the materials including the electrically conductive base metal material does not occur at portions sandwiched between adjacent positive and negative electrode layers among the dielectric ceramic layers.

Laminate-type dielectric device, a production method and an electrode paste material

A PZT dielectric ceramic material is sintered at a desired low temperature to prevent deterioration of the performance of the base material. An auxiliary oxide is used that is made by adding the oxide of at least one of tungsten and molybdenum to lead oxide in the following proportions:PbO+(WO+MoO)where x+y+z=1, 0.005&#x3c;y+z&#x3c;0.4 and y, z&#x2267;0. 0.5 mol % to 20 mol % of this auxiliary oxide is added to a mixture of a stock material of dielectric ceramic material or its calcination having a composition of ABOtype dielectric ceramic material where 0.9 molar ratio or more lead is included in site A assuming the proportion of site B is 1, and the material is mixed, formed and sintered. The content of tungsten and molybdenum combined is less than 0.098 mole in proportion to 1 mole of lead and the density of the dielectric ceramic material after sintering is 7.5 g/cmlarger. The auxiliary oxide is dispersed in the calcined powder to form a liquid phase at a desired temperature, to accelerate the sintering, thus making it possible to sinter at a lower temperature.

Dielectric ceramic material and method for producing the same

A method of manufacturing large-sized laminated dielectrics of high quality which permit adjustment of the atmosphere during sintering process to be accomplished easily, and which can eliminate the problems such as expansion due to reaction with the atmosphere gas. When a laminated body , consisting of oxide dielectric layers and inner electrode layers having a base metal such as Cu as a main component, is sintered in a reducing atmosphere, a mixed gas having CO gas as a main component and containing optional amount of CO gas and O gas is used. By using the equilibrium system of CO &rlarr;2CO&plus;(1/2)O and adjusting the amounts of CO gas and O gas, oxygen partial pressure in the atmosphere gas can be easily and stably adjusted and fluctuation and variation in the atmosphere can be suppressed.

Method for manufacturing laminated dielectrics

An integrally fired, laminated electromechanical transducing element, fabricated using an inexpensive electrode material and having the electrode characteristic at least equivalent to that of the Ag&mdash;Pd electrode, is disclosed. Especially, in the integrally fired, laminated electromechanical transducing element according to the invention, (A) the rigidity of the internal electrode layers is low and the internal stress generated at the time of expansion or contraction of the ceramic layers is small, (B) the antimigration characteristic is superior, (C) the charge loss is small, the heat conductivity is high and the heat radiation characteristic is superior, and/or (D) the bonding strength between the ceramic layers and the electrode layers is high. The integrally fired, laminated electromechanical transducing element ( ) according to the invention comprises, for example, an integrally fired laminate member fabricated by integrally firing a plurality of the ceramic layers ( ) of piezoelectric ceramic or electrostrictive ceramic and the internal electrode layers ( ) interposed between the ceramic layers ( ). The main component of the internal electrode layers ( ) is a base metal having a rigidity of not more than 160 GPa.

Integrally fired, laminated electromechanical transducing element

A laminate type dielectric device is formed by alternately laminating dielectric ceramic layers and electrode layers and integrally baking the laminate product. The electrode layers are mainly made of an electrically conductive base metal material having greater standard Gibbs free energy for the formation of a metal oxide at a baking temperature than that of the ceramic material constituting the dielectric ceramic layers. Segregation of the materials including the electrically conductive base metal material does not occur at portions sandwiched between adjacent positive and negative electrode layers among the dielectric ceramic layers.

A solid object carrying a catalyzer thereon is placed in a closed reaction chamber into which test gases are supplied and is heated up to a temperature of 1000.degree. C. Adsorbates are formed on the surface of the solid object under the test gas flow in the closed reaction chamber. Infrared radiations radiated from the adsorbates are emitted through an infrared-transmissive window hermetically formed on a wall of the closed reaction chamber, and are analyzed by an infrared radiation spectrometer and observed by a microscope. The infrared-transmissive window is cooled down by a cooling device attached thereto so that the temperature of the window does not exceed a certain level, e.g., 200.degree. C. Thus, the adsorbates formed on the solid object can be detected and analyzed under conditions where the test gas is actually flowing and the temperature of the solid object is elevated up to a high level. Since the infrared-transmissive window is cooled down and prevented from being broken by heat, the detection and analysis of the adsorbates are performed safely.

Apparatus for detecting and analyzing adsorbates

An infrared spectrometer disperses a radiation ray from a catalyst which has been exposed to a gas for evaluation to adsorb adsorbates thereon, and outputs spectral data in accordance with a wavenumber of the radiation ray to a computer storing reference data. The computer normalizes the spectral data and the reference data, and then, it calculates a product of the normalized spectral data and the reference data. Thereafter, a function of the product is differentiated with respect to the wavenumber to obtain a differential function. Accordingly, a specified wavenumber for which the differential function is zero is determined, so that the common peak of the spectral data and the reference data at the specified wavenumber is accurately determined.

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Nishio, Japan

Atsuhiro Sumiya