Multilayer varistor

Patent metadata

Field	Value
Publication number	US-12354776-B2
Application number	US-202318099008-A
Country	US
Kind code	B2
Filing date	Jan 19, 2023
Priority date	Jan 31, 2022
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

A multilayer varistor according to the present disclosure includes a sintered compact, at least one pair of internal electrodes, and at least one pair of external electrodes. The sintered compact contains at least a Zn oxide and a Pr oxide. The at least one pair of internal electrodes are provided inside the sintered compact and contain, as a main component, at least one selected from the group consisting of Pd and Ag and, as a sub-component, an oxide of at least one element selected from the group consisting of Pr, Mn, Co, and Sb. The at least one pair of external electrodes are arranged to cover the sintered compact partially and electrically connected to the at least one pair of internal electrodes, respectively.

First claim

The invention claimed is:

1. A multilayer varistor comprising:
a sintered compact containing at least a Zn oxide and a Pr oxide;
at least one pair of internal electrodes provided inside the sintered compact, the at least one pair of internal electrodes containing, as a main component, at least one selected from the group consisting of Pd and Ag and containing, as a sub-component, an oxide of at least one element selected from the group consisting of Pr, Mn, Co, and Sb; and
at least one pair of external electrodes arranged to cover the sintered compact partially and electrically connected to the at least one pair of internal electrodes, respectively,
wherein Al is not contained in the at least one pair of internal electrodes.

2. The multilayer varistor of claim 1 , wherein
the at least one pair of internal electrodes each contain the sub-component, of which content is equal to or greater than 0.001% by mass and equal to or less than 2% by mass with respect to the main component thereof.

3. The multilayer varistor of claim 1 , wherein
the at least one pair of internal electrodes each contain Pr 6 O 11 as the sub-component thereof.

4. The multilayer varistor of claim 1 , wherein
in a part, located between the at least one pair of internal electrodes, of the sintered compact, a concentration of Pr relative to Zn in neighboring regions of the at least one pair of internal electrodes is at most three times as high as a concentration of Pr relative to Zn in regions adjacent to the neighboring regions.

5. The multilayer varistor of claim 1 , wherein
at least one element selected from the group consisting of In and Ga is not contained in the at least one pair of internal electrodes.

6. A multilayer varistor comprising:
a sintered compact containing at least a Zn oxide and a Pr oxide;
at least one pair of internal electrodes provided inside the sintered compact, the at least one pair of internal electrodes containing, as a main component, at least one selected from the group consisting of Pd and Ag and containing, as a sub-component, an oxide of at least one element selected from the group consisting of Pr, Mn, Co, and Sb; and
at least one pair of external electrodes arranged to cover the sintered compact partially and electrically connected to the at least one pair of internal electrodes, respectively,
wherein the at least one pair of internal electrodes each contain the sub-component, of which content is equal to or greater than 0.001% by mass and equal to or less than 2% by mass with respect to the main component thereof.

7. A multilayer varistor comprising:
a sintered compact containing at least a Zn oxide and a Pr oxide;
at least one pair of internal electrodes provided inside the sintered compact, the at least one pair of internal electrodes containing, as a main component, at least one selected from the group consisting of Pd and Ag and containing, as a sub-component, an oxide of at least one element selected from the group consisting of Pr, Mn, Co, and Sb; and
at least one pair of external electrodes arranged to cover the sintered compact partially and electrically connected to the at least one pair of internal electrodes, respectively,
wherein the at least one pair of internal electrodes each contain Pr 6 O 11 as the sub-component thereof.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Yamagishi Yuji
• Satou Yoshiyuki
• Mutou Naoki

Classifications

• H01C1/14

  Terminals or tapping points specially adapted for resistors; Arrangements of terminals or tapping points on resistors · CPC title

• H01C7/102

  Varistor boundary, e.g. surface layers (H01C7/12 takes precedence) · CPC title

• H01C17/06546

  Oxides of zinc or cadmium · CPC title

• H01C7/1006

  Thick film varistors · CPC title

• H01C7/18

  comprising a plurality of layers stacked between terminals · CPC title