Magnetic sheet and wirelessly charged magnetic member including same

Patent metadata

Field	Value
Publication number	US-9831022-B2
Application number	US-201415028174-A
Country	US
Kind code	B2
Filing date	Oct 8, 2014
Priority date	Oct 8, 2013
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

An embodiment of the present invention relates to a magnetic sheet having both an electromagnetic field shielding function and a heat dissipating function, and to a wirelessly charged magnetic member using same.

First claim

What is claimed is:

1. A magnetic sheet comprising:
a thin film formed from a base substrate composition including a binder resin and a plurality of particles of Fe-based alloy magnetic powder having a width-direction length (X) longer than a thickness-direction length (Y),
wherein a proportion of the particles of the magnetic powder oriented to have an angle (θ) with respect to total number of the particles of the magnetic powder is in a range of 30%˜99%, the angle being formed by an extension line of a cross section of each of the particles of the magnetic powder in a horizontal direction and an extension line of a horizontal plane of the base substrate wherein the angle is an acute angle, an obtuse angle or a straight angle,
wherein the plurality of particles of the magnetic powder in the base substrate has an apparent density of 0.2˜0.8 g/cm 3 ,
wherein the magnetic sheet is configured such that the base substrate has a thermal conductivity (Ta) in the width direction greater than a thermal conductivity (Tb) in the thickness direction,
wherein a ratio (Ta:Tb) of the thermal conductivity (Ta) in the width direction and the thermal conductivity (Tb) in the thickness direction is in a range of (5˜1.5):1,
wherein the thermal conductivity (Ta) in the width direction is in a range of 3 W/m·k to 10 W/m·k, and
wherein the Fe-based alloy comprises Si having a content by weight in a range of 1%-16%.

2. The magnetic sheet of claim 1 , wherein the magnetic powder satisfies a relationship in which an angle formed between an extension line (X 2 ) in the width-direction (X) of the particles of the magnetic powder and the extension line of the horizontal plane of the base substrate is in a range of 30° ˜60° at a central point (X 1 ) that is a center of the width-direction length (X) of the particles of the magnetic powder.

3. The magnetic sheet of claim 1 , wherein the plurality of particles of the magnetic powder satisfies a relationship in which a ratio of the width-direction length (X) and the thickness-direction length (Y) is in a range of (3˜80):1.

4. The magnetic sheet of claim 3 , wherein an average width-direction length (X) of the particles of the magnetic powder is in a range of 10˜100 μm.

5. The magnetic sheet of claim 1 , wherein the binder resin comprises at least one selected from the group consisting of a polyvinyl alcohol-based resin, a silicon-based resin, an epoxy-based resin, an acrylate-based resin, a urethane-based resin, a polyamide-based resin, and a polyimide-based resin.

6. The magnetic sheet of claim 5 , wherein a blending ratio of the magnetic powder and the binder resin is in a range of 70:30˜95:5 (based on weight).

7. A wirelessly charged magnetic member comprising:
two or more stacked magnetic sheets,
wherein each of the magnetic sheets comprises a thin film formed from a base substrate composition including a binder resin and a plurality of particles of Fe-based alloy magnetic powder having a width-direction length (X) longer than a thickness-direction length (Y),
wherein a proportion of the particles of the magnetic powder oriented to have an angle (θ) with respect to total number of the particles of the magnetic powder is in a range of 30%˜99%, the angle being formed by an extension line of a cross section of each of the particles of the magnetic powder in a horizontal direction and an extension line of a horizontal plane of the base substrate wherein the angle is an acute angle, an obtuse angle or a straight angle,
wherein the plurality of particles of the magnetic powder in the base substrate has an apparent density of 0.2˜0.8 g/cm 3 ,
wherein the thermal conductivity (Ta) in the width direction is in a range of 3 W/m·k to 10 W/m·k,
wherein a ratio (Ta:Tb) of the thermal conductivity (Ta) in the width direction and the thermal conductivity (Tb) in the thickness direction is in a range of (5˜15):1, and
wherein the Fe-based alloy comprises Si having a content by weight in a range of 1%-16%.

8. The wirelessly charged magnetic member of claim 7 ,
wherein the magnetic powder satisfies a relationship in which the angle formed between an extension line (X 2 ) in the width-direction (X) of the particles of the magnetic powder and the extension line of the horizontal plane of the base substrate is in a range of 30° ˜60° at a central point (X 1 ) that is a center of the width-direction length (X) of the particles of the magnetic powder.

9. The wirelessly charged magnetic member of claim 7 ,
wherein an average width-direction length (X) of the particles of the magnetic powder is in a range of 10˜100 μm, and
wherein the plurality of particles of the magnetic powder satisfies a relationship in which a ratio of the width-direction length (X) and the thickness-direction length (Y) is (3˜80):1.

10. The wirelessly charged magnetic member of claim 7 , wherein a blending ratio of the magnetic powder and the binder resin is in a range of 70:30˜95:5 (based on weight).

Assignees

• Lg Innotek Co Ltd
• Lg Innotek Co Ltd

Inventors

• Kim So Yeon
• Bae Seok
• Hyun Soon Young
• Yeom Jai Hoon
• Lee Sang Won
• Lee Hee Jung
• Choi Don Chul

Classifications

• H02J50/10

  using inductive coupling · CPC title

• H01M10/44

  Methods for charging or discharging (circuits for charging H02J7/00) · CPC title

• H01F10/007 Primary

  ultrathin or granular films (H01F10/005 and H01F10/3227 take precedence; applying ultrathin or granular layers to substrates H01F41/301) · CPC title

• H05K9/0075

  Magnetic shielding materials · CPC title

• H02J50/70

  involving the reduction of electric, magnetic or electromagnetic leakage fields · CPC title