Ngk Spark Plug Company, Limited

Yasuyuki Okimura

Kazushige Ohbayashi

Hisashi Kozuka

Takeshi Mitsuoka

Hiroshi Watanabe

Masato Yamazaki

Hideto Yamada

Takayuki Matsuoka

Toshiaki Kurahashi

Takashi Kasashima

Shinji Ban

Kazuaki Kitamura

Hitoshi Yokoi

Tadashi Hattori

Yoshihito Mizoguchi

Tomoki Yamaguchi

Mina Sato

Seiji Oya

Hiroaki Nakanishi

Tomohiro Nishi

Seiya Matsuda

Yoshiteru Honda

Akira Seike

Yoshinobu Hirose

Hiroshi Watanbe

A sintered electrically conductive oxide for an oxygen sensor electrode includes a crystal phase formed of a perovskite-type electrically conductive oxide containing at least La, Fe and Ni. The oxide has an absolute value of thermoelectromotive force at 770&#xb0; C. of 21.0 &#x3bc;V/K or less.

Sintered electrically conductive oxide for oxygen sensor electrode, and oxygen sensor using the same

An electrically conductive oxide sintered compact according to one embodiment of the present invention includes a crystal phase that has a perovskite oxide crystal structure represented by the composition formula: RECoCuNiOwhere RE is a rare-earth element; a+b+c+d=1; and 1.25&#x2264;x&#x2264;1.75, wherein the values of a, b, c and d respectively satisfy the following conditions: 0.474&#x2264;a&#x2264;0.512; 0.050&#x2264;b&#x2264;0.350; 0&#x2264;c&#x2264;0.250; and 0.050&#x2264;d&#x2264;0.350.

Electrically conductive oxide sintered compact, member for electrical conduction, gas sensor, piezoelectric element, and method for producing piezoelectric element

A gas sensor, characterized by having an electrode formed of a conductive oxide sintered body which contains a primary phase formed of a perovskite oxide containing at least La, Fe, and Ni; and a secondary phase formed of an LaMOphase or an LaMOphase (M=Co, Fe, Ni), wherein the conductive oxide sintered body has a conductivity of 300 S/cm or higher at room temperature.

Electrically conductive oxide sintered compact, member for electrical conduction, and gas sensor

A lead-free piezoelectric ceramic composition including an alkali niobate/tantalate perovskite oxide main phase having piezoelectric properties and a different metal oxide. The mole ratio (Na/K) between Na (sodium) and K (potassium) in the main phase is 0.40&#x3c;(Na/K)&#x3c;3.0. The main phase has a crystal structure in which (i) first spots corresponding to a primitive lattice period and (ii) second spots corresponding to the lattice period two times the primitive lattice period and being weaker than the first spots appear in an electron beam diffraction image entering from the &#x3c;100&#x3e; direction with the main phase represented as a pseudo-cubic crystal system. Also, the area ratio of a crystal phase reflecting the second spots in the main phase is 33% or less, and the maximum grain size of crystals reflecting the second spots in the main phase is 25 nm or less.

Lead-free piezoelectric ceramic composition, piezoelectric element using the same, and method of manufacturing lead-free piezoelectric ceramic composition

A lead-free piezoelectric ceramic composition including an alkali niobate/tantalate perovskite oxide main phase having piezoelectric properties and a different metal oxide subphase. The mole ratio (Na/K) between Na (sodium) and K (potassium) in the main phase assumes a value in a range represented by 0.40&#x3c;(Na/K)&#x3c;3.0. The main phase has a crystal structure in which (i) first spots corresponding to a primitive lattice period and (ii) second spots corresponding to the lattice period two times the primitive lattice period and being weaker than the first spots appear in an electron beam diffraction image entering from the &#x3c;100&#x3e; direction with the main phase represented as a pseudo-cubic crystal system.

A gas sensor including a conductive oxide sintered body, the sintered body including a crystal phase having a perovskite-type oxide crystal structure represented by a compositional formula: RECuFeNiOwherein RE represents a rare earth element, wherein the following conditions: a+b+c+d=1 and 1.25&#x2264;x&#x2264;1.75 are satisfied, and wherein a, b, c, and d satisfy the following conditions: 0.375&#x2264;a&#x2264;0.524; 0.050&#x3c;b&#x2264;0.200; 0.025&#x2264;c&#x2264;0.250; and 0.150&#x2264;d&#x2264;0.350. Also disclosed is a conductive oxide sintered body, a wiring board including a conductor layer formed of the conductive oxide sintered body and a gas sensor including an electrode formed of the conductive oxide sintered body.

Gas sensor, electrically conductive oxide sintered body, and wiring board

In a manufacturing method for a thermistor element () including: a thermistor portion () which is a sintered body formed from a thermistor material; and a pair of electrode wires () which are embedded in the thermistor portion () and at least one end portion of each of the electrode wires projects at an outer side of the thermistor portion (), the resistance value of the thermistor element () is adjusted by performing a removal processing of removing a part of the thermistor portion ().

Thermistor element and manufacturing method therefor

A lead-free piezoelectric ceramic composition includes a first crystal phase made of an alkali niobate/tantalate type perovskite oxide having piezoelectric properties, and a second crystal phase made of an M-Ti&#x2014;O spinel compound (where the element M is a monovalent to quadrivalent element).

Unleaded piezoelectric ceramic composition, piezoelectric element using same, device, and method for manufacturing unleaded piezoelectric ceramic composition

A lead-free piezo-electric porcelain composition which contains a main phase having voids and which is formed of a first crystal phase composed of an alkali niobate/tantalate-based perovskite oxide having piezo-electric characteristics; and a sub-phase containing a second crystal phase composed of an ABO-based compound (where the element A is a monovalent element and the element B is one or more divalent to hexavalent elements). The sub-phase fills voids present in the main phase.

Lead-free piezo-electric porcelain composition, piezo-electric element using the same, and method for producing lead-free piezo-electric porcelain composition

A sintered electroconductive oxide having a perovskite oxide type crystal structure represented by a compositional formula: M1M2MnAlCrOwherein M1 represents at least one element selected from group 3 elements; and M2 represents at least one element selected from among Mg, Ca, Sr and Ba, wherein element M1 predominantly includes at least one element selected from Nd, Pr and Sm, and a, b, c, d, e and f satisfy the following relationships: 0.6005&#x2266;a&#x3c;1.000, 0&#x3c;b&#x2266;0.400, 0&#x2266;c&#x3c;0.150, 0.400&#x2266;d&#x3c;0.950, 0.050&#x3c;e&#x2266;0.600, 0.50&#x3c;e/(c+e)&#x2266;1.00, and 2.80&#x2266;f&#x2266;3.30. Also disclosed is a thermistor element including a thermistor portion which is formed of the sintered electroconductive oxide as well as a temperature sensor employing the thermistor element.

Sintered electrically conductive oxide, thermistor element employing the oxide, and temperature sensor employing the thermistor

A thermistor element includes a thermistor main body having a rectangular parallelepiped shape, and a first covering layer having reduction resistance and covering the periphery of the thermistor main body. At least a portion (exposed outer surface) of the outer surface of the first covering layer is exposed to the outside. When the shortest distance in a straight line in the first covering layer extending from a starting point on the thermistor main body to the exposed outer surface is defined as an exposed layer thickness at the starting point, the first covering layer is formed such that an exposed layer thickness measured by using any vertex of the rectangular parallelepiped thermistor main body as a starting point is equal to or greater than the smallest one of exposed layer thicknesses measured by using points on three sides and three flat surfaces which form the vertex.

Thermistor element, temperature sensor, and method for manufacturing the thermistor element

A conductive sintered oxide which includes: a conductive crystal phase having a perovskite structure represented by (RESr)MO, in which RE is a group of elements consisting of Yb and/or Lu and at least one element selected from Group IIIA elements excluding Yb, Lu and La, and M is a group of elements consisting of Al and at least one element selected from Groups IVA, VA, VIA, VIIA and VIII, a first insulating crystal phase represented by REO, and a second insulating crystal phase represented by SrAlO. The conductive crystal phase has a coefficient c satisfying 0.18&#x3c;c&#x3c;0.50 and has a coefficient d satisfying 0.67&#x2266;d&#x2266;0.93. A content of a third insulating crystal phase represented by REAlO, the content of which may be zero, is smaller than the content of each of the first and second insulating crystal phases.

Conductive sintered oxide, thermistor element including the same, and temperature sensor including the same

A sintered electroconductive oxide forming a thermistor element has a first crystal phase having a composition represented by RE1AlOand a second crystal phase having a perovskite structure represented by (RE2SL)MO. The factor a of the second crystal phase is: 0.18&#x3c;a&#x3c;0.50, wherein RE1 represents at least one of Yb and Lu and at least one species selected from among group 3A elements excluding Yb, Lu, and La; RE2 represents at least one species selected from among group 3A elements excluding La and which contains at least one species selected from the group RE1; M represents Al and at least one species selected from group 4A to 7A, and 8 elements; and SL represents Sr, Ca, and Mg, with at least Sr being included at a predominant proportion by mole.

Electrically conductive oxide sintered compact, thermistor element employing the same, and temperature sensor employing the same

According to an aspect of the present invention, there is provided a sintered electroconductive oxide containing a perovskite phase of perovskite-type crystal structure represented by the composition formula: M1M2M3AlCrOwhere M1 is at least one of elements of group 3A other than La; M2 is at least one of elements of group 2A; M3 is at least one of elements of groups 4A, 5A, 6A, 7A and 8 other than Cr; and a, b, c, d, e and f satisfy the following conditional expressions:0.600&#x2266;a&#x2266;1.000;0&#x2266;b&#x2266;0.400;0.150&#x2266;c&#x3c;0.600;0.400&#x2266;d&#x2266;0.800;0&#x3c;e&#x2266;0.050;0&#x3c;/()&#x2267;0.18; and2.80&#x2266;f&#x2266;3.30.With the use of this conductive oxide sintered body, it becomes possible to carry out proper temperature measurements over the temperature range from a low temperature of &#x2212;40&#xb0; C. to a high temperature of 900&#xb0; C. or higher.

Sintered electroconductive oxide, thermister element using sintered electroconductive oxide, and temperature sensor using thermister element

A thermistor element includes a thermistor body and a reduction-resistant coating covering the thermistor body. The thermistor body contains a perovskite phase of perovskite-type crystal structure represented by the composition formula: ABOwhere A is at least one A-site element and B is at least one B-site element. The reduction-resistant coating is formed of a complex oxide containing one or more of the at least one A-site element and one or more of the at least one B-site element.

Growing community of inventors

Inuyama, Japan

Yasuyuki Okimura