Magnetic shielding sheet and method of preparation thereof

Patent metadata

Field	Value
Publication number	US-10999959-B2
Application number	US-202016796718-A
Country	US
Kind code	B2
Filing date	Feb 20, 2020
Priority date	Feb 22, 2019
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

The present disclosure relates to a magnetic shielding sheet and a method of preparation thereof. The magnetic shielding sheet includes a magnetic layer, and a protective layer disposed on at least one surface of the magnetic layer. The magnetic layer includes a metal-ceramic composite that is metal powder, on which a ceramic coating layer is formed.

First claim

What is claimed is:

1. A magnetic shielding sheet, comprising:
a magnetic layer; and
a protective layer disposed on at least one surface of the magnetic layer, wherein
the magnetic layer comprises a metal-ceramic composite that is a metal powder, on which a ceramic coating layer is formed,
wherein a saturation magnetization value of the magnetic layer is 160 emu/g or more.

2. The magnetic shielding sheet of claim 1 , wherein
the metal powder comprises one or more metal materials selected from the group consisting of Fe, Fe—Co, Fe—Si, Fe—Al, and Fe—Mn.

3. The magnetic shielding sheet of claim 1 , wherein
the ceramic coating layer comprises one or more of ceramic materials selected from the group of MgO, Al 2 O 3 , SiO 2 , and, Y 2 O 3 .

4. The magnetic shielding sheet of claim 1 , wherein
in a criterion of 100% by weight of the metal-ceramic composite,
the metal powder is 60 to 90% by weight and the ceramic coating layer is 10 to 40% by weight.

5. The magnetic shielding sheet of claim 1 , wherein
the magnetic layer has 400 kW/m 3 or less of a core loss value at 100 kHz.

6. A method of preparing a magnetic shielding sheet, comprising:
(a) preparing a metal-ceramic composite by forming a ceramic coating layer on a surface of a metal powder; and
(b) preparing the magnetic shielding sheet by stacking a protective layer and a magnetic layer comprising the metal-ceramic composite,
wherein a saturation magnetization value of the magnetic layer is 160 emu/g or more.

7. The method of preparing the magnetic shielding sheet of claim 6 , wherein
the step of (a) comprises:
preparing a precursor solution comprising a metal material and a ceramic material; and
preparing a metal-ceramic composite by heat-treating the precursor solution within a reactor and passing through a partial reduction process.

8. The method of preparing the magnetic shielding sheet of claim 6 , wherein
the metal powder comprises one or more metal materials selected from the group consisting from Fe, Fe—Co, Fe—Si, Fe—Al, and Fe—Mn.

9. The method of preparing the magnetic shielding sheet of claim 6 , wherein
the ceramic coating layer comprises one or more ceramic materials selected from the group consisting from MgO, Al 2 O 3 , SiO 2 , and, Y 2 O 3 .

Assignees

• Lg Electronics Inc

Inventors

• Kim Jin Bae
• Kang Dongwon
• Kim Joungwook

Classifications

• B22F1/16

  Metallic particles coated with a non-metal (coated with lubricating or binding agents or with organic material B22F1/10) · CPC title

• H01F10/142

  containing Si · CPC title

• H01Q1/526

  Electromagnetic shields · CPC title

• H01F1/147

  Alloys characterised by their composition {(treatment thereof for enhancing their electromagnetic properties C21D8/12)} · CPC title

• H01F1/33

  mixtures of metallic and non-metallic particles; metallic particles having oxide skin · CPC title