Coating liquid and method for manufacturing thermoelectric member

Patent metadata

Field	Value
Publication number	US-11274217-B2
Application number	US-201916959686-A
Country	US
Kind code	B2
Filing date	Feb 19, 2019
Priority date	Mar 12, 2018
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

A coating liquid includes aluminum phosphate, a nonionic surfactant, and water and/or water-soluble solvent that dissolves or disperses the aluminum phosphate and the nonionic surfactant. An amount of the nonionic surfactant is preferably 1 vol % or more and 10 vol % or less. The nonionic surfactant is preferably at least one selected from the group consisting of ester, ether, alkylglycoside, octylphenol ethoxylate, pyrrolidone, and polyhydric alcohol. Applying such a coating liquid to a surface of a thermoelectric member, and drying and firing the coating liquid enables formation of a dense antioxidant film containing aluminum phosphate on the surface of the thermoelectric member.

First claim

What is claimed is:

1. A coating liquid comprising:
aluminum phosphate;
a nonionic surfactant; and
water and/or water-soluble solvent that dissolves or disperses the aluminum phosphate and the nonionic surfactant,
wherein the coating liquid does not contain silica particles, and
wherein an amount of the nonionic surfactant is 1 vol % or more and 10 vol % or less.

2. The coating liquid according to claim 1 , wherein the nonionic surfactant is at least one selected from the group consisting of ester, ether, alkylglycoside, octylphenol ethoxylate, pyrrolidone, and polyhydric alcohol.

3. The coating liquid according to claim 1 , wherein the coating liquid is employed for surface coating of an intermetallic compound-based thermoelectric material.

4. The coating liquid according to claim 3 , wherein the thermoelectric material is P-type bismuth telluride.

5. A method for manufacturing a thermoelectric member, the method comprising:
applying the coating liquid according to claim 1 to a surface of a thermoelectric member to form a coating film;
drying the coating film to obtain a precursor film; and
firing the thermoelectric member provided with the precursor film.

6. The coating liquid according to claim 1 , wherein an amount of the nonionic surfactant is 5 vol % or more and 10 vol % or less.

7. The coating liquid according to claim 1 , wherein an amount of the nonionic surfactant is 7.5 vol % or more and 10 vol % or less.

8. The coating liquid according to claim 1 , wherein the aluminum phosphate is present in an amount of 20 wt % or more.

Assignees

• Toyota Chuo Kenkyusho Kk

Inventors

• Matsubara Masato
• Saiki Yumi
• Asahi Ryoji

Classifications

• C01B19/04

  Binary compounds {including binary selenium-tellurium compounds (C01B19/004, C01B19/005, C01B19/007 take precedence)} · CPC title

• C09D7/63

  organic · CPC title

• C09D5/084

  Inorganic compounds · CPC title

• C01B25/36

  Aluminium phosphates · CPC title

• C09D7/48 Primary

  Stabilisers against degradation by oxygen, light or heat · CPC title