Flame-retardant composite magnetic body

Patent metadata

Field	Value
Publication number	US-10829617-B2
Application number	US-201615743173-A
Country	US
Kind code	B2
Filing date	Jul 6, 2016
Priority date	Jul 10, 2015
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

Provided is a composite magnetic body composite magnetic body including a flaky metallic soft magnetism powder with a volume content of 35% or more and 55% or less, wherein the composite magnetic body is characterized by further including a phosphazene compound, a binder resin, and a phosphorus-free flame retardant auxiliary so that equations (1) and (2) are satisfied:

0.17≤ P/B ≤0.21  (1)

0.89≤( PN +RA)/ B ≤2.71  (2)

(In the equations, PN denotes the mass % of the phosphazene compound in the composite magnetic body, RA denotes the mass % of the flame retardant auxiliary in the composite magnetic body, B denotes the mass % of the binder resin in the composite magnetic body, and P denotes the mass % of phosphorus in the composite magnetic body.) The composite magnetic body can impart high flame retardancy without losing performance such as magnetic permeability.

First claim

The invention claimed is:

1. A composite magnetic body comprising a flaky metallic soft magnetism powder with a volume content of 35% or more and 55% or less, wherein the composite magnetic body further comprises a phosphazene compound, a binder resin, and a phosphorus-free flame retardant auxiliary so that equations (1) and (2) are satisfied:
0.17 ≤P/B≤ 0.21  (1)

0.89≤( PN +RA)/ B≤ 2.71  (2)

(In the equations, PN denotes the mass % of the phosphazene compound in the composite magnetic body, RA denotes the mass % of the flame retardant auxiliary in the composite magnetic body, B denotes the mass % of the binder resin in the composite magnetic body, and P denotes the mass % of phosphorus in the composite magnetic body).

2. The composite magnetic body according to claim 1 , wherein the phosphazene compound is polybisphenoxyphosphazene.

3. The composite magnetic body according to claim 1 , wherein the phosphazene compound is admixed to the composite magnetic body as an organic binding material by dissolving in a solvent along with the binder resin.

4. The composite magnetic body according to claim 1 , wherein the binder resin is alkyl acrylate copolymer.

5. The composite magnetic body according to claim 1 , wherein the phosphorus-free flame retardant auxiliary is selected from metal hydroxides and nitrogenous cyclic compounds.

6. The composite magnetic body according to claim 1 , wherein the composite magnetic body further comprises a silane compound.

7. A magnetic sheet molded into a sheet from the composite magnetic body according to claim 1 .

8. A production method of a magnetic sheet comprising molding into a sheet using a hot press from the composite magnetic body according to claim 1 .

9. A magnetic sheet molded into a sheet from the composite magnetic body according to claim 2 .

10. A magnetic sheet molded into a sheet from the composite magnetic body according to claim 3 .

11. A magnetic sheet molded into a sheet from the composite magnetic body according to claim 4 .

12. A magnetic sheet molded into a sheet from the composite magnetic body according to claim 5 .

13. A magnetic sheet molded into a sheet from the composite magnetic body according to claim 6 .

14. A production method of a magnetic sheet comprising molding into a sheet using a hot press from the composite magnetic body according to claim 2 .

15. A production method of a magnetic sheet comprising molding into a sheet using a hot press from the composite magnetic body according to claim 3 .

16. A production method of a magnetic sheet comprising molding into a sheet using a hot press from the composite magnetic body according to claim 4 .

17. A production method of a magnetic sheet comprising molding into a sheet using a hot press from the composite magnetic body according to claim 5 .

Assignees

• Tokin Corp

Inventors

• Igarashi Toshiyuki
• Yoshida Hiroyuki
• Fuji Masahiko
• Abe Masakazu

Classifications

• C08K5/544

  containing nitrogen · CPC title

• H01F41/0246

  Manufacturing of magnetic circuits by moulding or by pressing powder (magnetic cores made by moulding or by pressing powder H01F27/255; soft magnetic particles H01F1/20, H01F1/36) · CPC title

• C08K3/016

  Flame-proofing or flame-retarding additives · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C08K2003/2224

  Magnesium hydroxide · CPC title