公开(公告)号：US12057260B2

公开(公告)日：2024-08-06

申请号：US16957397

申请日：2019-01-11

Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.

Inventor： Daisuke Kodama ,  Masahiro Gotoh

IPC: H01F3/08 ,  B22F1/05 ,  B22F1/102 ,  B22F1/16 ,  H01F1/147 ,  H01F27/255

CPC classification number: H01F3/08 ,  B22F1/05 ,  B22F1/102 ,  B22F1/16 ,  H01F1/14766 ,  H01F27/255 ,  B22F2301/35 ,  B22F2302/256 ,  B22F2304/10 ,  B22F2999/00 ,  B22F1/16 ,  C22C33/02 ,  C22C2202/02 ,  B22F3/02 ,  B22F3/10 ,  B22F1/05 ,  B22F2998/10 ,  B22F1/102 ,  B22F1/145 ,  B22F1/16 ,  C22C33/02

Abstract: A silicon oxide-coated iron powder has a small particle diameter, can achieve high in a high frequency band, and has high insulating property. In a method for producing the powder, a silicon alkoxide is added to a slurry containing iron powder having an average particle diameter of 0.25 μm or more and 0.80 μm or less and an average axial ratio of 1.5 or less dispersed in a mixed solvent of water and an organic material containing water in an amount of 1% by mass or more and 40% by mass or less. Then, a hydrolysis catalyst for the silicon alkoxide is added to perform silicon oxide coating, the method resulting in a silicon oxide-coated iron powder having the high μ′ in a high frequency band and the high insulating property.