# US 2017/0287604 A1 · Composite magnetic sealing material

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- Number: US 2017/0287604 A1
- Document ID: US20170287604A1
- Status: Published application
- Kind: A1
- Application number: 15/351,701
- Filed: 2016-11-15
- Published: 2017-10-05
- Earliest claimed: 2016-03-31
- Assignees: TDK Corporation
- Applicants: TDK Corporation
- Inventors: KENICHI KAWABATA
- Web page: https://patentgrep.com/patent/US20170287604A1

## CPC

- H10W 76/60: Seals
- H01F 1/14758: {by macromolecular organic substances}
- H10W 42/20: protecting against electromagnetic or particle radiation, e.g. light, X-rays, gamma-rays or electrons
- H10W 42/276: {the arrangements being on an external surface of the package, e.g. on the outer surface of an encapsulation}
- H10W 42/284: {shielding resins}
- H10W 42/287: {materials for magnetic shielding, e.g. ferromagnetic materials}
- H10W 74/473: {containing a filler}
- H10W 74/114: {by a substrate and the encapsulations}
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
- H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES

## Abstract

Disclosed herein is a composite magnetic sealing material includes a resin material and a filler blended in the resin material in a blended ratio of 30 vol. % or more to 85 vol. % or less. The filler includes a magnetic filler containing Fe and 32 wt. % or more and 39 wt. % or less of a metal material contained mainly of Ni, thereby a thermal expansion coefficient of the composite magnetic sealing material is 15 ppm/° C. or less.

## Claims

### Claim 1

A composite magnetic sealing material comprising:
a resin material; and
a filler blended in the resin material in a blended ratio of 30 vol. % or more to 85 vol. % or less,
wherein the filler includes a magnetic filler containing Fe and 32 wt. % or more and 39 wt. % or less of a metal material composed mainly of Ni, thereby a thermal expansion coefficient of the composite magnetic sealing material is 15 ppm/° C. or less.

### Claim 2 (depends on 1)

The composite magnetic sealing material as claimed in claim 1, wherein the metal material further contains 0.1 wt. % or more and 8 wt. % or less of Co relative to a total weight of the magnetic filler.

### Claim 3 (depends on 1)

The composite magnetic sealing material as claimed in claim 1, wherein the filler further includes a non-magnetic filler.

### Claim 4 (depends on 3)

The composite magnetic sealing material as claimed in claim 3, wherein a ratio of an amount of the non-magnetic filler relative to a sum of an amounts of the magnetic filler and the non-magnetic filler is 1 vol. % or more and 40 vol. % or less.

### Claim 5 (depends on 4)

The composite magnetic sealing material as claimed in claim 4, wherein the non-magnetic filler contains at least one material selected from a group consisting of SiO2, ZrW2O8, (ZrO)2P2O7, KZr2(PO4)3, or Zr2(WO4)(PO4)2.

### Claim 6 (depends on 1)

The composite magnetic sealing material as claimed in claim 1, wherein the magnetic filler has a substantially spherical shape.

### Claim 7 (depends on 1)

The composite magnetic sealing material as claimed in claim 1, wherein the magnetic filler is coated with an insulating material.

### Claim 8 (depends on 7)

The composite magnetic sealing material as claimed in claim 7, wherein a film thickness of the insulating material is 10 nm or more.

### Claim 9 (depends on 1)

The composite magnetic sealing material as claimed in claim 1, wherein the resin material comprises a thermosetting resin material.

### Claim 10 (depends on 9)

The composite magnetic sealing material as claimed in claim 9, wherein the thermosetting resin material contains at least one material selected from a group consisting of an epoxy resin, a phenol resin, a urethane resin, a silicone resin, or an imide resin.

### Claim 11 (depends on 1)

The composite magnetic sealing material as claimed in claim 1, wherein a volume resistivity of the composite magnetic sealing material is 1010 W cm or more.

### Claim 12

A composite magnetic sealing material comprising:
a resin material;
a magnetic filler formed of an Fe—Ni based material blended in the resin material, the magnetic filler containing Fe and 32 wt. % or more and 39 wt. % or less of a metal material composed mainly of Ni; and
a non-magnetic filler blended in the resin material,
wherein a ratio of an amount of the non-magnetic filler relative to a sum of an amounts of the magnetic filler and the non-magnetic filler is 1 vol. % or more and 40 vol. % or less, and
wherein a thermal expansion coefficient of the composite magnetic sealing material is 15 ppm/° C. or less.

### Claim 13

(canceled)

### Claim 14 (depends on 12)

The composite magnetic sealing material as claimed in claim 12,
wherein the magnetic filler is coated with an insulating material having a film thickness is 10 nm or more.

### Claim 15 (depends on 12)

The composite magnetic sealing material as claimed in claim 12, wherein the non-magnetic filler contains at least one material selected from a group consisting of SiO2, ZrW2O8, (ZrO)2P2O7, KZr2(PO4)3, or Zr2(WO4)(PO4)2.

### Claim at position 16

16-19. (canceled)