公开(公告)号：US11247265B2

公开(公告)日：2022-02-15

申请号：US16316060

申请日：2017-07-10

Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.

Inventor： Hidenori Yamaji ,  Masahiro Gotoh

IPC: B22F1/00 ,  B22F1/02 ,  C01G49/06 ,  H01F1/20 ,  B22F9/22 ,  B22F3/00 ,  C22C38/00 ,  H01F1/24 ,  B22F9/04

Abstract: An iron powder and method of making an iron powder. The method includes a step of neutralizing an acidic aqueous solution containing a trivalent iron ion and a phosphorus-containing ion, with an alkali aqueous solution, so as to provide a slurry of a precipitate of a hydrated oxide, or a step of adding a phosphorus-containing ion to a slurry containing a precipitate of a hydrated oxide obtained by neutralizing an acidic aqueous solution containing a trivalent iron ion with an alkali aqueous solution. A silane compound is added to the slurry so as to coat a hydrolysate of the silane compound on the precipitate of the hydrated oxide. The precipitate of the hydrated oxide after coating is recovered through solid-liquid separation, the recovered precipitate is heated to provide iron particles coated with a silicon oxide, and a part or the whole of the silicon oxide coating is dissolved and removed.

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.

公开(公告)号：US20220148775A1

公开(公告)日：2022-05-12

申请号：US17427178

申请日：2020-01-30

Applicant: Dowa Electronics Materials Co., Ltd.

Inventor： Hidenori Yamaji ,  Masahiro Gotoh

IPC: H01F1/34 ,  H05K9/00 ,  C01G49/00

Abstract: There are provided a magnetoplumbite-type hexagonal crystal ferrite magnetic powder which can be suitably used as the material of a radio wave absorber having an excellent radio wave absorbing power in the 76 GHz band, and a method for producing the same. In a method for producing a magnetoplumbite-type hexagonal crystal ferrite magnetic powder, the method comprising the steps of: mixing powders of the raw materials of a magnetoplumbite-type hexagonal crystal ferrite magnetic powder, which is expressed by a compositional formula of AFe(12-x)AlxO19 (A is at least one selected from the group consisting of Sr, Ba, Ca and Pb, x=1.0 to 2.2), to obtain a mixture; granulating and molding the mixture to obtain molded bodies; firing the molded bodies to obtain fired bodies; and pulverizing the fired bodies, there are prepared a plurality of firing containers (firing scabbards 10), each of which has an opening of the upper face thereof and a notch (10a) formed in the upper portion of the side face thereof so as to be communicated with the outside thereof, each of the firing containers being filled with the molded bodies, and the firing containers being stacked in a plurality of stages so as to close the opening of the top face of the lower firing container, to fire the molded bodies in a firing furnace (20).

公开(公告)号：US20150108392A1

公开(公告)日：2015-04-23

申请号：US14391274

申请日：2013-05-07

Applicant: DOWA Electronics Materials, Co., Ltd.

Inventor： Masahiro Gotoh ,  Takayuki Yoshida ,  Kazumasa Ikari

IPC: H01F1/33 ,  H01F1/147 ,  H01F1/20

CPC classification number: H01F1/33 ,  B22F1/0018 ,  B22F1/02 ,  B82Y30/00 ,  C22C19/07 ,  C22C33/02 ,  C22C38/005 ,  C22C38/06 ,  C22C38/10 ,  C22C2202/02 ,  H01F1/0063 ,  H01F1/147 ,  H01F1/20 ,  H01F1/26 ,  H01F3/08 ,  H01F17/045 ,  H01Q7/08 ,  H01Q9/0421 ,  Y10T428/12014

Abstract: In magnetic parts such as inductors and antennas using magnetic metal powder, the complex component of a magnetic permeability, which represents a loss in a GHz band, has been high.A magnetic part formed from a soft magnetic metal powder including iron as a main component can reduce a loss factor in a kHz to GHz band. The soft magnetic metal powder has an average particle diameter of 100 nm or less, an axial ratio (=major axis length/minor axis length) of 1.5 or more, a coercive force (Hc) of 39.8 to 198.9 kA/m (500 to 2500 Oe), and a saturation magnetization of 100 Am2/kg or more.

Abstract translation: 在使用磁性金属粉末的诸如电感器和天线的磁性部件中，磁导率的复合分量代表GHz带中的损耗已经很高。 由包含铁作为主要成分的软磁性金属粉末形成的磁性部件可以减小kHz至GHz频带的损耗因子。 软磁性金属粉末的平均粒径为100nm以下，轴比（=长轴长/短轴长）为1.5以上，矫顽力（Hc）为39.8〜198.9kA / m（500〜 2500Oe），饱和磁化强度为100Am 2 / kg以上。

公开(公告)号：US11114228B2

公开(公告)日：2021-09-07

申请号：US15578471

申请日：2016-06-01

Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.

Inventor： Toshihiko Ueyama ,  Masahiro Gotoh ,  Takayuki Yoshida ,  Takuyuki Baba

IPC: H01F1/26 ,  H01F1/11 ,  B22F1/00 ,  B22F1/02

Abstract: A magnetic compound having a small dielectric loss and an antenna constituted by the magnetic compound and an electronic device incorporating the antenna are provided by a metal magnetic powder which is well dispersed in a resin having small dielectric loss, and a magnetic powder composite including: a metal magnetic powder; and one or more elements selected from carboxylic acid or its anhydride, aromatic carboxylic acid ester, and a derivative thereof, having a property that real part μ′ permeability is 1.45 or more, tan δμ is 0.1 or less, tan δε is 0.05 or less at a measuring frequency of 2 GHz, when a magnetic powder composite is prepared by adding 5 parts by mass of one or more elements selected from the carboxylic acid or its anhydride, the aromatic carboxylic acid ester, and the derivative thereof to 100 parts by mass of the metal magnetic powder.

公开(公告)号：US11103922B2

公开(公告)日：2021-08-31

申请号：US15129032

申请日：2015-03-27

Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.

Inventor： Masahiro Gotoh ,  Takayuki Yoshida

IPC: B22F1/00 ,  C22C38/00 ,  H01Q7/08 ,  H01Q9/04 ,  H01F1/26 ,  C22C38/10 ,  H01R13/719 ,  H01F1/24 ,  H01F1/33 ,  B22F9/26

Abstract: A method for producing a Fe—Co alloy powder suitable for an antenna includes steps, wherein when introducing an oxidizing agent into an aqueous solution containing Fe ions and Co ions to generate crystal nuclei and cause precipitation and growth of a precursor having Fe and Co as components, Co in an amount corresponding to 40% or more of the total amount of Co used for the precipitation reaction is added to the aqueous solution at a time after the start of the crystal nuclei generation and before the end of the precipitation reaction to obtain the precursor. Then, a dried product of the precursor is reduced to obtain a Fe—Co alloy powder. This Fe—Co alloy powder has a mean particle size of 100 nm or less, a coercive force Hc of 52.0 to 78.0 kA/m, and a saturation magnetization ss of 160 Am2/kg or higher.

公开(公告)号：US11056257B2

公开(公告)日：2021-07-06

申请号：US15578411

申请日：2016-06-01

Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.

Inventor： Takayuki Yoshida ,  Masahiro Gotoh ,  Toshihiko Ueyama ,  Takuyuki Baba ,  Toru Suzuki ,  Koji Tanaka

IPC: H01F1/26 ,  H01F1/20 ,  H01F1/28 ,  B22F1/00 ,  C08K3/08 ,  C08K9/04 ,  C08L81/02 ,  C08K3/40 ,  C08K7/14

Abstract: An object is to provide a magnetic compound excellent in high frequency properties and excellent in mechanical strength, and its related items, using the polyarylene sulfide resin, and to provide a technique regarding the magnetic compound having a metal magnetic powder and a polyarylene sulfide resin, and satisfying both mechanical strength and high frequency properties.

公开(公告)号：US20150104664A1

公开(公告)日：2015-04-16

申请号：US14372342

申请日：2013-03-13

Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.

Inventor： Kazumasa Ikari ,  Masahiro Gotoh ,  Takayuki Yoshida

IPC: H01F1/147 ,  H01F1/20 ,  B22F1/00 ,  H01Q1/36 ,  B22F9/24 ,  B22F1/02 ,  H01F7/02 ,  H01F27/255

CPC classification number: B22F9/26 ,  B22F1/0018 ,  B22F1/02 ,  B22F9/24 ,  B22F2201/03 ,  B22F2301/35 ,  B22F2302/25 ,  B22F2303/01 ,  C22C2202/02 ,  H01F1/20 ,  H01F1/26 ,  H01F17/045 ,  H01F27/255 ,  H01F27/292 ,  H01Q1/364 ,  Y10T428/12014

Abstract: In a magnetic component, such as an inductor and an antenna, produced with a metal magnetic powder, a complex number component of magnetic permeability that is a loss in the GHz band was high.A magnetic component obtained by molding a soft magnetic metal powder can have a reduced loss factor in the GHz band. The soft magnetic metal powder is characterized by containing iron as a main ingredient, and having an average particle size of not larger than 300 nm, a coercive force (Hc) of 16 to 119 kA/m (200 to 1500 Oe), a saturation magnetization of not less than 90 Am2/kg, and a volume resistivity of not less than 1.0×101 Ω·cm. The volume resistivity is determined by measuring, by a four probe method, a molded body formed by vertically pressurizing 1.0 g of the metal powder at 64 MPa (20 kN).

Abstract translation: 在由金属磁性粉末制成的磁电元件（例如电感器和天线）中，在GHz频带中的损耗的磁导率的复数分量高。 通过模制软磁性金属粉末获得的磁性部件可以具有在GHz带中降低的损耗因子。 软磁性金属粉末的特征在于以铁为主要成分，平均粒径为300nm以下，矫顽力（Hc）为16〜119kA / m（200〜1500Oe），饱和度 磁化强度不小于90Am2 / kg，体积电阻率不小于1.0×101Ω·cm·cm。 通过四探针法测定通过在64MPa（20kN）下垂直加压1.0g金属粉末形成的成型体来确定体积电阻率。