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

Patent metadata

Field	Value
Publication number	US-9790098-B2
Application number	US-201615090783-A
Country	US
Kind code	B2
Filing date	Apr 5, 2016
Priority date	Apr 6, 2015
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

A sintered electroconductive oxide having a perovskite oxide type crystal structure represented by a compositional formula: M1 a M2 b Mn c Al d Cr e O f wherein 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≦a<1.000, 0<b≦0.400, 0≦c<0.150, 0.400≦d<0.950, 0.050<e≦0.600, 0.50<e/(c+e)≦1.00, and 2.80≦f≦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.

First claim

What is claimed is:

1. A sintered electroconductive oxide having a perovskite oxide type crystal structure represented by a compositional formula: M1 a M2 b Mn c Al d Cr e O f wherein M1 represents at least one element selected from group 3 elements; and M2 represents at least one element selected from the group consisting of Mg, Ca, Sr and Ba, wherein element M1 predominantly includes at least one element selected from the group consisting of Nd, Pr and Sm, and a, b, c, d, e and f satisfy the following relationships:
0.600≦ a< 1.000,

0< b≦ 0.400,
0≦ c< 0.150,

0.400≦ d< 0.950,

0.050< e≦ 0.600,
0.50< e /( c+e )≦1.00, and

2.80≦ f≦ 3.30.

2. The sintered electroconductive oxide as claimed in claim 1 , wherein c and e satisfy 0.65≦e/(c+e)≦1.00.

3. The sintered electroconductive oxide as claimed in claim 1 , wherein a, b, c d, e and f satisfy the following relationships:
0.700≦ a< 1.000,

0< b≦ 0.300,
0≦ c< 0.140,

0.500< d< 0.950,
0.050< e≦ 0.500,
0.65< e /( c+e )≦1.00, and

2.80≦ f≦ 3.30.

4. The sintered electroconductive oxide as claimed in claim 1 , wherein M1 is at least one element selected from the group consisting of Nd, Pr and Sm, and M2 is at least one element selected from the group consisting of Ca and Sr.

5. A thermistor element comprising a thermistor portion which is formed of the sintered electroconductive oxide as claimed in claim 1 .

6. A temperature sensor comprising the thermistor element as claimed in claim 5 .

Assignees

• Ngk Spark Plug Co

Inventors

• Watanabe Hiroshi
• Ban Shinji
• Yamaguchi Tomoki
• Okimura Yasuyuki
• Nishi Tomohiro

Classifications

• C04B2235/768

  Perovskite structure ABO3 · CPC title

• C04B2235/602

  Making the green bodies or pre-forms by moulding · CPC title

• C04B2235/3206

  Magnesium oxides or oxide-forming salts thereof · CPC title

• C04B2235/3205

  Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide · CPC title

• C04B2235/3241

  Chromium oxides, chromates, or oxide-forming salts thereof · CPC title