Method of manufacturing barium titanate and electronic component of barium titanate

Patent metadata

Field	Value
Publication number	US-9796631-B2
Application number	US-201514938329-A
Country	US
Kind code	B2
Filing date	Nov 11, 2015
Priority date	Jun 12, 2013
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A method of manufacturing barium titanate powder by dispersing, in a solvent such as ethanol, barium titanate. Then, the barium titanate is separated from the slurry by evaporating the solvent while pressurizing the slurry in a pressure container. Then, the separated barium titanate is subjected to a heat treatment, thereby producing the barium titanate powder.

First claim

The invention claimed is:

1. A method of manufacturing barium titanate powder the method comprising:
providing a slurry containing barium titanate dispersed in a solvent;
separating the barium titanate from the slurry by evaporating the solvent while pressurizing the slurry; and
heat-treating the separated barium titanate to produce the barium titanate powder, wherein the barium titanate that is dispersed in the slurry is obtained by a reaction caused by adding barium hydroxide to a titanium oxide slurry containing titanium oxide powder dispersed in water.

2. The method of manufacturing barium titanate powder according to claim 1 , wherein the solvent is at least one of a water-based solvent, an organic-based solvent, and a water-based and organic-based solvent.

3. The method of manufacturing barium titanate powder according to claim 1 , wherein the solvent is ethanol.

4. The method of manufacturing barium titanate powder according to claim 3 , wherein a concentration of the ethanol in the solvent is 5 vol %.

5. The method of manufacturing barium titanate powder according to claim 1 , wherein the barium titanate is separated from the slurry by pressurizing the slurry by putting the slurry into a container, heating the slurry from an outside of the container, filling the container with a gas from the outside of the container, and evaporating the solvent from the slurry.

6. The method of manufacturing barium titanate powder according to claim 5 , wherein the gas is N 2 .

7. The method of manufacturing barium titanate powder according to claim 1 , wherein the barium titanate is separated from the slurry by pressurizing the slurry by putting the slurry into a container, heating the slurry from an outside of the container, and evaporating the solvent from the slurry.

8. The method of manufacturing barium titanate powder according to claim 1 , wherein the barium titanate is separated from the slurry by pressurizing the slurry by putting the slurry into a container and filling the container with a gas from an outside of the container.

9. The method of manufacturing barium titanate powder according to claim 8 , wherein the gas is N 2 .

10. The method of manufacturing barium titanate powder according to claim 1 , wherein a specific surface area of the barium titanate dispersed in the slurry is 65 m 2 /g.

11. The method of manufacturing barium titanate powder according to claim 10 , wherein a c/a axis ratio of the barium titanate dispersed in the slurry is 1.0000.

12. The method of manufacturing barium titanate powder according to claim 1 , wherein a c/a axis ratio of the barium titanate dispersed in the slurry is 1.0000.

13. The method of manufacturing barium titanate powder according to claim 1 , wherein the slurry is pressurized at 0.2 MPa.

14. The method of manufacturing barium titanate powder according to claim 1 , wherein the heat treating of the separated barium titanate is carried out at a temperature of 800° C. to 1000° C.

15. The method of manufacturing barium titanate powder according to claim 1 , wherein a c/a axis ratio of the produced barium titanate powder is 1.009 or more.

16. The method of manufacturing barium titanate powder according to claim 11 , wherein a c/a axis ratio of the produced barium titanate powder is 1.009 or more.

17. The method of manufacturing barium titanate powder according to claim 12 , wherein a c/a axis ratio of the produced barium titanate powder is 1.009 or more.

Assignees

• Murata Manufacturing Co

Inventors

• Konishi Shinya
• Fujii Kazuya
• Nada Kazushige

Classifications

• C04B2235/5454

  nanometer sized, i.e. below 100 nm · CPC title

• C01P2006/12

  Surface area · CPC title

• C01P2004/62

  Submicrometer sized, i.e. from 0.1-1 micrometer · CPC title

• C04B35/4682 Primary

  based on BaTiO3 perovskite phase · CPC title

• H01G4/30

  Stacked capacitors (H01G4/33 takes precedence) · CPC title