WO2019054085A1 - Near-field noise-suppression sheet - Google Patents

Near-field noise-suppression sheet Download PDF

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Publication number
WO2019054085A1
WO2019054085A1 PCT/JP2018/029289 JP2018029289W WO2019054085A1 WO 2019054085 A1 WO2019054085 A1 WO 2019054085A1 JP 2018029289 W JP2018029289 W JP 2018029289W WO 2019054085 A1 WO2019054085 A1 WO 2019054085A1
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Prior art keywords
noise suppression
alloy powder
suppression sheet
flame retardant
less
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PCT/JP2018/029289
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French (fr)
Japanese (ja)
Inventor
雅規 蔵前
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株式会社リケン
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Priority to KR1020207004423A priority Critical patent/KR102155542B1/en
Priority to CN201880047397.6A priority patent/CN110892492B/en
Publication of WO2019054085A1 publication Critical patent/WO2019054085A1/en

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00—Screening of apparatus or components against electric or magnetic fields
    • H05K9/0073—Shielding materials
    • H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
    • H05K9/0083—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
    • C08J7/04—Coating
    • C08J7/05—Forming flame retardant coatings or fire resistant coatings
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/02—Elements
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/10—Metal compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/38—Boron-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L101/00—Compositions of unspecified macromolecular compounds
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C45/00—Amorphous alloys
    • C22C45/02—Amorphous alloys with iron as the major constituent
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/153—Amorphous metallic alloys, e.g. glassy metals
    • H01F1/15308—Amorphous metallic alloys, e.g. glassy metals based on Fe/Ni
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H01F1/28—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder dispersed or suspended in a bonding agent
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00—Screening of apparatus or components against electric or magnetic fields
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/08—Metallic powder characterised by particles having an amorphous microstructure

Definitions

  • the present invention relates to a near-field noise suppression sheet used to suppress extra radiated radio waves (noise) in electronic devices and communication devices.
  • a near-field noise suppression sheet (hereinafter, also referred to as a “noise suppression sheet”) capable of converting unnecessary radiated radio waves (noise) into heat and preventing unnecessary magnetic field coupling is used as equipment or the like.
  • this noise suppression sheet has a thickness of 0.05 mm to 2 mm, it can be inserted in the vicinity of an electronic component or electronic circuit, and is easy to process and has a high degree of freedom in shape. Therefore, the noise suppression sheet can be adapted to the miniaturization and weight reduction of the electronic device and the communication device, and is widely used as a noise countermeasure component of the electronic device and the communication device.
  • a typical noise suppression sheet comprises a soft magnetic alloy powder processed into a flat shape and an organic binder, and the noise suppression effect can be obtained by the magnetic loss of the soft magnetic alloy powder due to the magnetic resonance. Therefore, the noise suppression performance of the noise suppression sheet depends on the magnetic permeability of the soft magnetic alloy powder contained in the noise suppression sheet.
  • the imaginary part magnetic permeability ⁇ ′ ′ is distributed over the frequency band of radio wave noise to be absorbed (hereinafter also referred to as “target band”).
  • target band the distribution of the imaginary part magnetic permeability ⁇ ′ ′ with respect to frequency.
  • the ⁇ ′ dispersion differs in ⁇ ′ ′ value and distribution depending on the material and shape of the soft magnetic alloy powder contained in the noise suppression sheet. Therefore, in order to enhance the effect of noise suppression, it is necessary to select a noise suppression sheet suitable for the target band.
  • the target band is as low as the kHz to MHz band, and the transmission becomes higher as the frequency becomes higher.
  • the magnetic permeability decreases.
  • the ⁇ ′ ′ value substantially approaches 1, the noise suppression effect can not be exhibited.
  • Patent Documents 1 and 2 have a flat soft shape of Sendust composition.
  • a noise suppression sheet containing magnetic alloy powder and carbon powder has been proposed: In the low frequency band, the magnetic loss by the soft magnetic alloy powder is used, and in the high frequency band, the dielectric loss by the carbon powder is used.
  • the target band is wide band.
  • Patent Document 3 is characterized by mainly containing flat soft magnetic particles composed of an iron-based amorphous alloy and an organic binder, and having a complex relative magnetic permeability ⁇ ′ ′ of 7 or more at 10 GHz.
  • electromagnetic interference suppressing body which is described here, as the soft magnetic particles, the composition formula:.
  • Patent Documents 4 and 5 disclose soft magnetic alloys having a structure in which ⁇ -Fe crystals are precipitated in an amorphous state.
  • Patent Document 4 discloses an amorphous structure in which ⁇ -Fe crystal grains having an average particle diameter of 5 to 30 nm are precipitated, which has a composition formula: Fe 100-a-b-c-d Si a B b C c Cu d (where, 1% ⁇ a ⁇ 3% , 9% ⁇ b ⁇ 14%, 1% ⁇ c ⁇ 4%, 0.3% ⁇ d ⁇ 1.5%, 80% ⁇ 100-a A soft magnetic alloy represented by -b-c-d ⁇ 86%) is described.
  • Patent Document 5 has an amorphous structure in which ⁇ -Fe crystal grains having an average particle diameter of 5 to 30 nm are precipitated, and the compositional formula: Fe 100-a-b-c-d Si a P b C c Cu d (however, 0% ⁇ a ⁇ 3%, 9% ⁇ b ⁇ 13%, 4% ⁇ c ⁇ 6%, 0.3% ⁇ d ⁇ 1.5%, 80% ⁇ 100 ⁇ ab ⁇ A soft magnetic alloy represented by cd ⁇ 86%) is described. And as an example, it is described that these soft-magnetic alloys can be applied to magnetic parts, such as a noise suppression sheet
  • JP 2012-186384 A JP, 2013-182931, A JP, 2015-46538, A JP, 2016-94651, A Unexamined-Japanese-Patent No. 2016-94652 gazette
  • the magnetic permeability of the noise suppression sheet is influenced not only by the composition of the alloy powder but also by the degree of orientation and the filling rate of the flat alloy powder in the noise suppression sheet. That is, since the flat alloy powder has magnetic anisotropy in the in-plane direction, it is necessary to increase the degree of orientation of the alloy powder in the in-plane direction of the sheet to increase the magnetic permeability of the noise suppression sheet. .
  • the permeability of the noise suppression sheet is also influenced by the filling rate of the alloy powder contained in the sheet, and in order to increase the permeability of the noise suppression sheet, it is necessary to increase the density of the noise suppression sheet.
  • a flame retardant noise suppression sheet is required due to the nature of the target device using the noise suppression sheet, and it is general to add a flame retardant as a countermeasure.
  • the flame retardant is added, the degree of orientation of the flat alloy powder is lowered, and as a result, the magnetic permeability of the noise suppression sheet is lowered, and the frequency characteristics are also affected.
  • Patent Documents 4 and 5 aim to obtain a soft magnetic alloy excellent in soft magnetic properties by optimizing the component composition and structure of the soft magnetic alloy, but the degree of orientation of the alloy powder in the noise suppression sheet No mention is made of the density and flame retardancy of the noise suppression sheet. Therefore, even if the noise suppression sheet is produced using the soft magnetic alloys described in Patent Documents 4 and 5, in addition to the target band being the MHz to GHz band, a noise suppression sheet having not only flame resistance but also The current situation is that the
  • the flame-retardant noise suppressing sheet for the near field is characterized in that the rising frequency of the ⁇ ′ ′ dispersion is in the band of 1 to 10 MHz and the ⁇ ′ ′ dispersion is distributed to the GHz band. Intended to provide.
  • a noise suppressing sheet for a near field comprising: a base material made of an organic substance, a flat alloy powder supported in the base material, and a flame retardant dispersed in the base material,
  • the alloy powder has, in atomic percent, a composition formula: Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 (where 16 ⁇ X 1 + Y 1 ⁇ 24, 14.5 ⁇ X 1 ⁇ 24, and 0 ⁇ Y 1 ⁇ Alloy powder represented by 1.5) and / or a composition formula: Fe 100 -X 2 -Y 2 (Si, B, C) X 2 Cu Y 2 (where 16 ⁇ X2 + Y 2 ⁇ 24, 14.5 ⁇ X 2 ⁇ 24, and 0 Alloy powder represented by ⁇ Y 2 ⁇ 1.5),
  • the phase structure of the alloy powder is composed of only an amorphous phase or a mixture of an amorphous phase or a mixture of an amorphous phase or a
  • the alloy powder may be 19 ⁇ X1 + Y1 ⁇ 21, 18 ⁇ X1 ⁇ 21, and 0 ⁇ Y1 ⁇ 1.0, and / or 19 ⁇ X2 + Y2 ⁇ 21, 18 ⁇ X2 ⁇ 21, and 0 ⁇ Y2 ⁇
  • the frequency at which the ⁇ ′ ′ value is 1 or more is 1 MHz to 10 MHz, and the ⁇ ′ ′ value at 10 GHz is 2 or more.
  • the near-field noise suppression sheet described in (2) is 1 MHz to 10 MHz.
  • the flame retardant is one or more non-halogen flame retardants selected from among aluminum hydroxide, magnesium hydroxide, zinc borate, melamine cyanate, and red phosphorus.
  • the near-field noise suppression sheet according to any one of (4) to (4).
  • the Fe is substituted with one or more elements selected from Al, Co, Ni, Cr, Nb, Mo, Ta, and W.
  • the noise suppressing sheet for near field according to any one of (1) to (5).
  • the noise suppression sheet contains one or more oxides selected from silicon, titanium, aluminum and zirconium, and the particle size of the oxide is 100 nm or less.
  • the near-field noise suppression sheet according to any one of (1) to (10).
  • a near-field noise suppression sheet capable of coping with magnetic field noise in a broad band of MHz to GHz band and also having flame retardancy.
  • a near-field noise suppression sheet includes a base made of an organic substance, a flat alloy powder supported in the base, and a flame retardant dispersed in the base.
  • the flat alloy powder has, in atomic percent, a composition formula: Fe 100 -X 1 -Y 1 (Si a P b C c ) X 1 Cu Y 1 (where 16 ⁇ X1 + Y1 ⁇ 24, 14.5 ⁇ X1 ⁇ 24, and 0 An alloy powder represented by ⁇ Y1 ⁇ 1.5 and / or a composition formula: Fe 100 ⁇ X 2 ⁇ Y 2 (Si d B e C f ) X 2 Cu Y 2 (where 16 ⁇ X 2 + Y 2 ⁇ 24, 14.5 ⁇ X 2 ⁇ And an alloy powder represented by 0 ⁇ Y2 ⁇ 1.5).
  • Fe 100 -X 1 -Y 1 (Si a P b C c ) X 1 Cu Y 1 is expressed as Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 and Fe 100 -X 2 -Y 2 Si d B e C f) X2 Cu Y2 of Fe 100-X2-Y2 (Si , denoted B, C) and X2 Cu Y2.
  • the total amount of Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 and Fe 100-X 2-Y 2 (Si, B, C) X 2 Cu Y 2 is preferably 50 mass% or more.
  • the ratio of each alloy powder in the case where both Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 and Fe 100-X 2-Y 2 (Si, B, C) X 2 Cu Y 2 are contained is not particularly limited. .
  • the phase structure of the alloy powder having the above composition has a structure consisting only of an amorphous phase.
  • those containing Cu are mixed with an amorphous phase and a crystalline phase mainly composed of ⁇ -Fe by performing annealing treatment described later to precipitate ⁇ -Fe crystals. It can also be a matter of course.
  • ⁇ -Fe is the main component means that the volume ratio of ⁇ -Fe in the crystal phase is 50% or more, preferably 70% or more.
  • X1, X2 and Y1, Y2 of the above composition have 19 ⁇ X1 + Y1 ⁇ 21, 18 ⁇ X1 ⁇ 21, and 0 ⁇ Y1 ⁇ 1.0, and / or 19 ⁇ X2 + Y2 ⁇ It is preferable to satisfy 21, 18 ⁇ X2 ⁇ 21, and 0 ⁇ Y2 ⁇ 1.0.
  • 3 atomic% or less of Fe may be substituted with one or more elements selected from Al, Co, Ni, Cr, Nb, Mo, Ta, and W.
  • the total addition amount of the elements to be substituted exceeds 3 atomic%, the saturation magnetization of the alloy powder is significantly reduced, whereby the magnetic permeability of the noise suppression sheet is reduced. Therefore, the upper limit value is 3 atomic%.
  • a flat alloy powder, an organic matter, a flame retardant, and an organic solvent are mixed to prepare a slurry.
  • the raw material powder As a raw material powder of alloy powder, it is preferable to use a powder having the above-mentioned composition, and to make the shape of the raw material powder spherical.
  • the raw material powder can be obtained by a gas atomization method or a water atomization method which is a general powder synthesis method.
  • the average particle diameter of raw material powder means the particle diameter (50% accumulated particle diameter: D50) in 50% of the integration value in the particle size distribution calculated
  • Flat alloy powder is obtained by mechanical processing of such spherical raw material powder.
  • the average value of the thickness of the flat alloy powder is 0.1 ⁇ m or more It is preferable to carry out flattening so as to be 1.5 ⁇ m or less.
  • the average value of the aspect-ratio of alloy powder may be 10 or more and 100 or less.
  • the average value of the aspect ratio is 10 or more, the influence of the demagnetizing field in the plane of the flat alloy powder can be ignored, and if 100 or less, the degree of orientation of the alloy powder in the in-plane direction of the sheet is This is because it is possible to obtain a noise suppression sheet which is increased during film formation and has a flat surface.
  • known or arbitrary machining such as a ball mill, attritor, or stamp mill can be suitably used.
  • the “average value of thickness” is obtained by observing the ion milling polished surface of the cross section in the thickness direction of the noise suppression sheet produced by the method described later with a scanning electron microscope (SEM) and viewing in the visual field.
  • the mean value of the thickness of the flat alloy powder is meant for 10 powders, and the “average value of the aspect ratio” is also 10 in the field of view as observed by SEM.
  • the value of the ratio of length / thickness of the flat alloy powder is averaged for the powder of
  • the alloy powder is annealed in an inert atmosphere such as nitrogen or argon.
  • an inert atmosphere such as nitrogen or argon.
  • the annealing conditions may be, for example, a temperature of 200 to 500 ° C. and a time of 0.5 to 5 hours.
  • an alloy powder having a desired coercive force can be obtained by appropriately selecting the annealing conditions and controlling the phase structure of the alloy powder.
  • the coercive force of the alloy powder is preferably 0.5 A / cm or more and 8 A / cm or less.
  • the ⁇ ′ ′ dispersion start frequency can be present in the MHz band, and if 8 A / cm or less, ⁇ ′ ′ of sufficient size to suppress noise It is because a value can be obtained.
  • a self-oxidized film or an externally treated film on the surface of the flat alloy powder for the purpose of applying an insulation treatment.
  • the means and material for film formation are not particularly limited as long as they can maintain insulation.
  • the thickness of the film is suitably 20 to 100 nm, and if the film is formed more than necessary, the volume of the magnetic phase decreases, so it is not possible to obtain a sufficiently large ⁇ ′ ′ value.
  • a heat treatment in the air or a heat treatment in a hydrocarbon-based organic solvent is a typical method, and as a method of forming an external treatment film, a vapor phase method such as dip coating or CVD.
  • the order of the above-mentioned insulation treatment and annealing treatment is not particularly limited.
  • the flat alloy powder may also be surface-treated with one or more coupling agents selected from silicon, titanium, aluminum and zirconium.
  • the method of coupling treatment is not particularly limited, and a typical treatment method will be described here. That is, the flat alloy powder is charged into a solvent in which the above-mentioned coupling agent is dissolved, and after stirring, the alloy powder is recovered and dried at a temperature of 100 to 200 ° C., for example. Thereby, an oxide having a particle size of 100 nm or less is formed on the surface of the alloy powder.
  • the degree of familiarity with an organic substance to be described later is improved, and a noise suppression sheet having a high packing density of the alloy powder can be obtained.
  • a ⁇ ′ ′ value large enough for noise suppression can be obtained.
  • particles of insulating oxide resulting from the coupling agent are formed on the surface of the flat alloy powder, it also contributes to the improvement of the insulation of the alloy powder.
  • an organic substance which comprises a base material the thing which does not contain a halogen element is preferable. This is because, in the conventional noise suppression sheet, organic substances such as chlorinated polyethylene having high flame retardancy were used, but in recent years, a noise suppression sheet containing no halogen element is required by environmental regulations such as the RoHS directive. It is from.
  • a halogen element for example, any resin material such as epoxy resin, phenol resin, cellulose resin, polyethylene resin, polyester resin, or any rubber material such as silicone rubber, acrylic rubber, nitrile rubber, butyl rubber Materials, and arbitrary fiber materials such as non-woven fabric, polyester fiber, acrylic fiber, etc.
  • organic substance may be mentioned, and the selection of the organic substance may be appropriately selected according to the purpose.
  • organic substances have functions such as imparting of cohesion and plasticity, and isolation of alloy powders.
  • a plasticizer such as dioctyl phthalate can be added as needed to enhance the flexibility of the noise suppression sheet.
  • the average particle diameter of the finally obtained noise suppression sheet is 10 ⁇ m or less, preferably 0.2 ⁇ m to 8 ⁇ m, and more preferably 0.2 ⁇ m to 6 ⁇ m. Since the flame retardant is present dispersed in the flat alloy powder, when the average particle size exceeds 10 ⁇ m, the degree of orientation of the alloy powder in the in-plane direction of the sheet is significantly reduced. Therefore, even if the flame retardancy can be enhanced, the desired noise suppression effect can not be obtained. In addition, if the average particle diameter of a flame retardant is 0.2 micrometer or more, high flame retardance can be maintained.
  • the average particle diameter of the flame retardant refers to the average value of the major axes of the ten flame retardants in the field of view when the ion milling polished surface of the cross section in the thickness direction of the noise suppression sheet is observed by SEM. means.
  • the type of the flame retardant is not particularly limited, but it is preferably a flame retardant containing no halogen element as in the organic substance, and specifically, aluminum hydroxide, magnesium hydroxide, zinc borate, melamine cyanate, and One or more flame retardants selected from red phosphorus may be mentioned.
  • the mixing ratio of the flat alloy powder, the flame retardant, and the organic substance is 5 parts by mass to 30 parts by mass of the flame retardant and 8 parts by mass to 30 parts of the organic substance when the flat alloy powder is 100 parts by mass. It is preferable to set it as part or less. If the flame retardant is 5 parts by mass or more, it becomes V1 or more in the flame retardancy test of UL94 standard, and the flame retardancy required for the noise suppression sheet can be secured, and if 30 parts by mass or less, the noise suppression This is because it is possible to suppress the magnetic permeability of the noise suppression sheet from being significantly reduced because the volume ratio of the alloy powder to the entire sheet is not significantly reduced.
  • the organic substance is 8 parts by mass or more, the plasticity of the noise suppression sheet can be maintained, and if it is 30 parts by mass or less, the flat alloy powder is easily oriented in the horizontal direction of the sheet at the time of sheet molding. If the organic matter is added at such a compounding ratio, the surface resistance of the noise suppression sheet is 10 5 ⁇ / s even without the above-mentioned insulation treatment.
  • the insulation property of the alloy powder itself is improved, so that the amount of the organic substance added can be reduced as compared with the case where the insulation treatment is not performed. Since the volume of the alloy powder in the noise suppression sheet is improved, the permeability is increased and the flame retardancy is also improved.
  • the organic solvent is not particularly limited, and toluene, butyl acetate, ethyl acetate and the like can be used.
  • the organic solvent is not included in the noise suppression sheet because it is evaporated in the subsequent step.
  • the slurry can be produced by a known ball mill method. That is, flat alloy powder, flame retardant, organic substance, and organic solvent adjusted to a predetermined compounding ratio are charged into a container together with a ball mill media for promoting mixing and stirring, and these are rotated by rotating the container. A homogeneously dispersed slurry can be made.
  • the slurry in the present embodiment can also be produced using a ball mill method. However, in the ball mill method, a large external force is applied to the flat alloy powder by the ball mill media, and it becomes difficult to keep the coercivity of the flat alloy powder in the range of 0.5 A / cm to 8 A / cm.
  • a planetary mixing and stirring device that does not use ball media for the preparation of the slurry.
  • the flat alloy powder, the flame retardant, the organic substance, and the organic solvent can be homogeneously mixed without giving a large external force to the flat alloy powder.
  • the planetary stirring system promotes degassing of the gas contained in the slurry, it is possible to produce a slurry effective for obtaining a noise suppression sheet having a high density of 2.5 g / cm 3 or more. it can.
  • a slurry comprising a flat alloy powder, a flame retardant, an organic substance, and an organic solvent is formed into a sheet by a doctor blade method and dried to prepare a formed body.
  • This molded body has a structure in which a flat alloy powder is supported on a base made of an organic substance, and a flame retardant is dispersed between the alloy powders, and furthermore, a flat alloy is produced by shear stress during molding.
  • the powders are oriented horizontally to one another.
  • a known or arbitrary method such as a calendar roll method can be used, but when producing a noise suppression sheet having a thickness of 0.1 mm or less It is preferable to use a coating method such as a doctor blade method.
  • the sheet-like compact is pressed in a state of being heated to a temperature higher than the softening point of the organic substance (for example, about 60 to 150 ° C.) Apply.
  • the thickness of the noise suppression sheet obtained can be about 0.05 mm to 0.1 mm, and the density of the noise suppression sheet can also be 2.5 g / cm 3 or more. If the density is less than 2.5 g / cm 3 , the number of voids increases, the degree of horizontal orientation of the flat alloy powder decreases, and the ratio of the alloy powder to the whole sheet decreases, so the desired noise The suppression effect can not be obtained.
  • the density of the noise suppression sheet is preferably 2.7 g / cm 3 or more.
  • it is effective to increase the ratio of the alloy powder to the entire sheet by increasing the proportion of the flat alloy powder as much as possible as well as eliminating the voids.
  • a flame retardant noise suppression sheet characterized in that the rising frequency of the ⁇ ′ ′ dispersion is in the band of 1 MHz to 10 MHz and the ⁇ ′ ′ dispersion is distributed to the GHz band. it can. More specifically, in the noise suppression sheet, at the rise of the ⁇ ′ ′ dispersion, the frequency at which the ⁇ ′ ′ value is 1 or more is present in the band of 1 MHz to 10 MHz, and the ⁇ ′ ′ value at 10 GHz is 2 or more. ing.
  • the flame retardant may be added in advance when flattening the alloy powder, not when producing a slurry.
  • the flame retardant when the alloy powder is subjected to flattening processing, the flame retardant is also crushed and crushed, so the flame retardant contained in the noise suppression sheet even if the average particle size of the flame retardant when added is more than 10 ⁇ m. Can be adjusted to 10 ⁇ m or less.
  • Table 1 shows the phase structure measured by powder X-ray diffractometry and the coercivity measured by the coercivity measuring device for each flat alloy powder after the annealing treatment.
  • magnesium hydroxide 9 ⁇ m-red phosphorus 7 ⁇ m and the comparative examples 5 to 8 Magnesium hydroxide was 13 ⁇ m-red phosphorus 13 ⁇ m, magnesium hydroxide 8 ⁇ m-red phosphorus 7 ⁇ m for Inventive Example 11, and magnesium hydroxide 6 ⁇ m-red phosphorus 6 ⁇ m for Inventive Example 12.
  • this slurry was processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method.
  • Table 1 shows the frequency at which the ⁇ ′ ′ value becomes 1 or more and the magnitude of the ⁇ ′ ′ value at 10 GHz when the ⁇ ′ ′ dispersion starts to rise.
  • the component composition of the present invention is satisfied, the average particle diameter of the flame retardant is 10 ⁇ m or less, and the density of the noise suppression sheet is 2.5 g / cm 3 or more.
  • the frequency at which the value of ⁇ ′ ′ is 1 or more is in the range of 1 to 10 MHz, and the value of ⁇ ′ ′ at 10 GHz exceeds 2.
  • the magnetic characteristics are Possibly good, the ⁇ ′ ′ value at 10 GHz was above 4.5.
  • the ⁇ ′ ′ value at 10 GHz was less than 2.
  • Comparative Example 1 the magnetic flux density of the flat alloy powder also decreased due to the low Fe concentration, and the ⁇ ′ ′ value at 10 GHz Is considered to be less than two. Further, in Comparative Example 2, the component composition of the present invention is not satisfied, and since the coercive force of the flat alloy powder exceeds 8 A / cm, the soft magnetic characteristics are degraded, and the ⁇ ′ ′ value at 10 GHz is It is considered that it was less than 2. Further, in Comparative Examples 3 and 4 in which Cu exceeds 1.5 atomic%, it was found by X-ray diffraction measurement that a FeP compound having large magnetic anisotropy was formed.
  • the coercivity exceeded 8 A / cm
  • the distribution width of ⁇ ′ ′ with respect to the frequency was narrow
  • the ⁇ ′ ′ value at 10 GHz was also 0.0. If the ⁇ ′ ′ value at 10 GHz is 2 or more, it is possible to effectively suppress the noise generated in recent electronic devices that are reduced in size, size, size, and frequency, if the ⁇ ′s value at 10 GHz is 2 or more. It can be.
  • the average particle diameter of the flame retardant was more than 10 ⁇ m, and from the observation with SEM, a part where the in-plane orientation of the alloy powder was disturbed was confirmed everywhere. Therefore, at the beginning of the rise of the ⁇ ′ ′ dispersion, the frequency at which the ⁇ ′ ′ value is 1 or more exceeded 10 MHz, and the ⁇ ′ ′ value at 10 GHz was also below 2.
  • the density of the noise suppression sheet was less than 2.5 g / cm 3, and it was confirmed by SEM observation everywhere that the orientation in the sheet plane of the alloy powder was disturbed. Therefore, at the beginning of the rise of the ⁇ ′ ′ dispersion, the frequency at which the ⁇ ′ ′ value is 1 or more exceeded 10 MHz, and the ⁇ ′ ′ value at 10 GHz was also below 2.
  • the average particle diameter of the flame retardant is 8 ⁇ m or less, and the density of the noise suppression sheet is 2.7 g / cm 3 or more.
  • the above frequency is in the range of 1 to 10 MHz, and the ⁇ ′ ′ value at 10 GHz exceeds 5.
  • the in-plane orientation of the flat powder sheet as the average particle diameter of the flame retardant decreases. Becomes better, so that the ⁇ ′ ′ value at 10 GHz also becomes larger.
  • Table 2 shows the phase structure and the coercivity measured by the method described above.
  • each flat alloy powder 100 parts by mass of each flat alloy powder, 20 parts by mass of acrylic rubber (softening point: about 70 ° C.), 50 parts by mass of toluene, and 5 parts by mass of melamine cyanurate as a flame retardant and 1 part by mass of red phosphorus
  • the average particle diameter of the flame retardant at the time of adding is set to magnesium hydroxide 9 ⁇ m-red phosphorus 7 ⁇ m for Inventive Examples 13 to 22 and Comparative Examples 13 to 16 and 21 to 24, and Comparative Examples 17 to 20.
  • Magnesium hydroxide was 13 ⁇ m-red phosphorus 13 ⁇ m, magnesium hydroxide 8 ⁇ m-red phosphorus 7 ⁇ m for invention example 23, magnesium hydroxide 6 ⁇ m-red phosphorus 6 ⁇ m for invention example 24.
  • this slurry was processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method.
  • the permeability characteristics, the average particle diameter of the flame retardant, the density of the noise suppression sheet, and the surface resistance were measured by the methods described above for each of the invention examples and the comparative examples. The measurement results are shown in Table 2.
  • Comparative Example 13 the magnetic flux density of the flat alloy powder also decreased due to the low Fe concentration, and the ⁇ ′ ′ value at 10 GHz Is considered to be less than 2. Further, in Comparative Example 14, the component composition of the present invention is not satisfied, and since the coercive force of the flat alloy powder exceeds 8 A / cm, the soft magnetic characteristics are degraded, and the ⁇ ′ ′ value at 10 GHz is It is considered that it was less than 2. Further, in Comparative Examples 15 and 16 in which Cu exceeds 1.5 atomic%, it was found by X-ray diffraction measurement that a compound of FeB having large magnetic anisotropy was formed. As a result, the coercive force exceeded 8 A / cm, the distribution width of ⁇ ′ ′ with respect to frequency was narrow, and the ⁇ ′ ′ value at 10 GHz was also 0.0.
  • the average particle diameter of the flame retardant was more than 10 ⁇ m, and from the observation with SEM, a portion in which the in-plane orientation of the alloy powder was disturbed was confirmed everywhere. Therefore, at the beginning of the rise of the ⁇ ′ ′ dispersion, the frequency at which the ⁇ ′ ′ value is 1 or more exceeded 10 MHz, and the ⁇ ′ ′ value at 10 GHz was also below 2.
  • the density of the noise suppression sheet was less than 2.5 g / cm 3 , and SEM observation confirmed everywhere that the orientation in the sheet surface of the alloy powder was disturbed. Therefore, at the beginning of the rise of the ⁇ ′ ′ dispersion, the frequency at which the ⁇ ′ ′ value is 1 or more exceeded 10 MHz, and the ⁇ ′ ′ value at 10 GHz was also below 2.
  • the ⁇ ′ ′ value starts to rise, and the ⁇ ′ ′ value is 1
  • the above frequency is in the range of 1 to 10 MHz, and the ⁇ ′ ′ value at 10 GHz exceeds 5.
  • the in-plane orientation of the flat powder sheet as the average particle diameter of the flame retardant decreases. Becomes better, so that the ⁇ ′ ′ value at 10 GHz also becomes larger.
  • each flat alloy powder 20 parts by mass of polybutyral resin (softening point: about 70 ° C.), 50 parts by mass of butyl acetate, and 5 parts by mass of magnesium hydroxide having an average particle diameter of 6 ⁇ m as a flame retardant Parts and 1 part by mass of red phosphorus having an average particle diameter of 6 ⁇ m were mixed by a planetary mixing and stirring apparatus to prepare a slurry (Inventive Examples 26 and 27).
  • these slurries were processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method. Then, the noise suppression sheet
  • the average particle diameter of the flame retardant is 8 ⁇ m or less, and the density of the noise suppression sheet is 2.7 g / cm 3 or more.
  • the frequency of the above was in the range of 1 to 10 MHz, and the ⁇ ′ ′ value at 10 GHz exceeded 2.
  • the flat powder Orientation in the sheet plane was further improved, and the ⁇ ′ ′ value at 10 GHz exceeded 5.
  • the alloy powder was taken out of the solution and dried in the atmosphere at 150 ° C. for 8 hours to form an oxide having an average particle diameter of 100 nm or less on the surface of the alloy powder. Thereafter, annealing was performed in nitrogen at 350 to 450 ° C. for 30 minutes. Table 4 shows the phase structure and the coercivity measured by the method described above.
  • the ⁇ ′ ′ value starts to rise, ⁇ ′ ′ value is 1
  • the above frequency is in the range of 1 to 10 MHz, and the ⁇ ′ ′ value at 10 GHz is more than 2.
  • the total substitution amount of Al, Co, Ni, Cr, Nb, Mo, Ta, W to Fe is In the invention examples 28, 30, 32, 34 of 3 atomic% or less, the ⁇ ′ ′ value at 10 GHz was a high value of 2.5 or more.
  • the magnetic flux density of the alloy powder is reduced when the total of the substitution amounts of Al, Co, Ni, Cr, Nb, Mo, Ta, W with respect to Fe exceeds 3 atomic%, More preferably, the total of the substitutional amounts of Al, Co, Ni, Cr, Nb, Mo, Ta and W with respect to is 3 atomic% or less.
  • a near-field noise suppression sheet capable of coping with magnetic field noise in a broad band of MHz to GHz band and also having flame retardancy.

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Abstract

Provided is a fire-resistant near-field noise-suppression sheet wherein a rising frequency for a μ" distribution is present at 1 to 10 MHz and the μ" distribution spreads over to GHz bands. This near-field noise-suppression sheet is characterized by the inclusion of a base material comprising an organic material, a flat-shaped alloy powder held within the base material, and a fire-retardant dispersed within the base material, the alloy powder being an Fe100-X1-Y1(Si,P,C)X1CuY1 alloy powder (16 ≤ X1+Y1 ≤ 24, 14.5 ≤ X1 ≤ 24, 0 ≤ Y1 ≤ 1.5) and/or an Fe100-X2-Y2(Si,B,C)X2CuY2 alloy powder (16 ≤ X2+Y2 ≤ 24, 14.5 ≤ X2 ≤ 24, 0 ≤ Y2 ≤ 1.5), the phase structure thereof comprising non-crystalline phases only, or a phase wherein a non-crystalline phase and an α-Fe main body crystal phase are mixed, the mean particle diameter of the fire-retardant being 10 μm or smaller, and the density thereof being 2.5 g/cm3 or greater.

Description

近傍界用ノイズ抑制シートNear field noise suppression sheet
　本発明は、電子機器や通信機器における余分な放射電波（ノイズ）を抑制するために使用される近傍界用ノイズ抑制シートに関する。 The present invention relates to a near-field noise suppression sheet used to suppress extra radiated radio waves (noise) in electronic devices and communication devices.
　近年、電子機器や通信機器の小型化および軽量化に伴い、電子回路に装着される部品の実装密度が高くなっている。そのため、電子部品から放射される電波ノイズに起因して、電子部品同士間あるいは電子回路同士間において電波干渉や磁界結合が生じることによる電子機器や通信機器の誤動作が問題となる。 2. Description of the Related Art In recent years, with the miniaturization and weight reduction of electronic devices and communication devices, the mounting density of components mounted on electronic circuits has been increasing. Therefore, the malfunction of the electronic device or the communication device caused by the radio wave interference and the magnetic field coupling between the electronic components or the electronic circuits due to the radio wave noise radiated from the electronic components becomes a problem.
　この問題を防ぐために、余分な放射電波（ノイズ）を熱に変換し、不要な磁界結合を防ぐことができる近傍界用ノイズ抑制シート（以下、「ノイズ抑制シート」とも称する。）が機器などに実装されている。このノイズ抑制シートは、厚さが０．０５ｍｍ～２ｍｍであることから、電子部品や電子回路近傍に挿入することが可能であり、加工が容易で形状自由度も高い。そのため、ノイズ抑制シートは、電子機器や通信機器の小型化および軽量化に適応することができ、電子機器や通信機器のノイズ対策部品として広く用いられている。 In order to prevent this problem, a near-field noise suppression sheet (hereinafter, also referred to as a “noise suppression sheet”) capable of converting unnecessary radiated radio waves (noise) into heat and preventing unnecessary magnetic field coupling is used as equipment or the like. Has been implemented. Since this noise suppression sheet has a thickness of 0.05 mm to 2 mm, it can be inserted in the vicinity of an electronic component or electronic circuit, and is easy to process and has a high degree of freedom in shape. Therefore, the noise suppression sheet can be adapted to the miniaturization and weight reduction of the electronic device and the communication device, and is widely used as a noise countermeasure component of the electronic device and the communication device.
　典型的なノイズ抑制シートは、偏平状に加工された軟磁性合金粉末と有機結合剤からなり、軟磁性合金粉末の磁気共鳴による磁気損失によってノイズ抑制効果が得られる。よって、ノイズ抑制シートのノイズ抑制性能は、ノイズ抑制シートに含まれる軟磁性合金粉末の透磁率に依存する。一般に、透磁率は、実部透磁率μ’と虚数部透磁率μ”を用いて複素透磁率μ＝μ’－ｊ・μ”で表されるが、ノイズ抑制シートのように磁気損失を利用する場合には、虚数部透磁率μ”が重要になる。すなわち、吸収したい電波ノイズの周波数帯域（以下、「対象帯域」とも称する。）にわたって、虚数部透磁率μ”が分布することが重要である。以下、本明細書では、周波数に対する虚数部透磁率μ”の分布を「μ”分散」と称する。μ”分散は、ノイズ抑制シートに含まれる軟磁性合金粉末の材質および形状に応じて、μ”値や分布が異なる。そのため、ノイズ抑制の効果を高めるには、対象帯域に適したノイズ抑制シートを選択する必要がある。 A typical noise suppression sheet comprises a soft magnetic alloy powder processed into a flat shape and an organic binder, and the noise suppression effect can be obtained by the magnetic loss of the soft magnetic alloy powder due to the magnetic resonance. Therefore, the noise suppression performance of the noise suppression sheet depends on the magnetic permeability of the soft magnetic alloy powder contained in the noise suppression sheet. In general, the magnetic permeability is expressed by complex magnetic permeability μ = μ'-j · μ "using real part magnetic permeability μ 'and imaginary part magnetic permeability μ", but magnetic loss is used like a noise suppression sheet In this case, the imaginary part magnetic permeability μ ′ ′ is important. That is, it is important that the imaginary part magnetic permeability μ ′ ′ is distributed over the frequency band of radio wave noise to be absorbed (hereinafter also referred to as “target band”). Hereinafter, the distribution of the imaginary part magnetic permeability μ ′ ′ with respect to frequency is referred to as “μ ′ dispersion” in the present specification. The μ ′ ′ dispersion differs in μ ′ ′ value and distribution depending on the material and shape of the soft magnetic alloy powder contained in the noise suppression sheet. Therefore, in order to enhance the effect of noise suppression, it is necessary to select a noise suppression sheet suitable for the target band.
　例えば、いわゆるセンダスト組成のＦｅ-Ｓｉ-Ａｌ系合金に代表されるような偏平状の軟磁性合金粉末を使用したノイズ抑制シートでは、対象帯域がｋＨｚ～ＭＨｚ帯と低く、周波数が高くなるにつれて透磁率が減少する。特に、ＧＨｚ帯域においては、μ”値が実質的に１に近づくために、ノイズ抑制効果を発揮することができない。これに対応すべく、特許文献１，２では、センダスト組成の偏平状の軟磁性合金粉末と炭素粉末とを含むノイズ抑制シートが提案されている。すなわち、周波数の低い帯域では軟磁性合金粉末による磁気損失を利用し、周波数の高い帯域では炭素粉末による誘電損失を利用することで、対象帯域を広帯域としている。 For example, in a noise suppression sheet using a flat soft magnetic alloy powder represented by a so-called Sendust composition Fe-Si-Al alloy, the target band is as low as the kHz to MHz band, and the transmission becomes higher as the frequency becomes higher. The magnetic permeability decreases. In particular, in the GHz band, since the μ ′ ′ value substantially approaches 1, the noise suppression effect can not be exhibited. In order to cope with this, Patent Documents 1 and 2 have a flat soft shape of Sendust composition. A noise suppression sheet containing magnetic alloy powder and carbon powder has been proposed: In the low frequency band, the magnetic loss by the soft magnetic alloy powder is used, and in the high frequency band, the dielectric loss by the carbon powder is used. The target band is wide band.
　また、磁性部材の透磁率は、磁性部材の電気抵抗にも影響され、ノイズ抑制シートのμ”分散を高周波化させるには、電気抵抗の大きな軟磁性合金粉末を使用するのが有利である。したがって、結晶質の軟磁性合金よりも電気抵抗が大きい非晶質の軟磁性合金を使用することがμ”分散の高周波化に有効な手段である。例えば、特許文献３には、鉄系の非晶質合金からなる偏平状の軟磁性粒子と有機結合剤を主に含有し、１０ＧＨｚにおける複素比透磁率μ”が７以上であることを特徴とする電磁干渉抑制体が記載されている。ここで、上記軟磁性粒子としては、組成式：｛Ｆｅａ（ＳｉｘＢｙＰｚ）１－ａ｝１００－ｂＬｂ（但し、ＬはＡｌ、Ｃｒ、Ｚｒ、Ｎｂ、Ｍｏ、Ｈｆ、Ｔａ、Ｗから選ばれる１種以上の元素、０．７０≦ａ≦０．８２原子％、０＜ｂ≦８原子％、０．０５≦ｘ≦０．６０原子％、０．１０≦ｙ≦０．８５原子％、０．０５≦ｚ≦０．７０原子％、ｘ＋ｙ＝ｚ＝１）で表わされる粒子や、組成式：（Ｆｅ１－ａＴＭａ）１００－ｗ－ｘ－ｙ－ｚＰｗＢｘＬｙＳｉｚ（但し、ＴＭはＣｏ、Ｎｉから選ばれる１種以上の元素、ＬはＡｌ、Ｖ、Ｃｒ、Ｙ、Ｚｒ、Ｍｏ、Ｎｂ、Ｔａ、Ｗから選ばれる１種以上の元素、０≦ａ≦０．９８原子％、２≦ｗ≦１６原子％、２≦ｘ≦１６原子％、０＜ｙ≦１０原子％、０≦ｚ≦８原子％）で表わされる粒子が挙げられている。 The magnetic permeability of the magnetic member is also affected by the electrical resistance of the magnetic member, and it is advantageous to use a soft magnetic alloy powder having a large electrical resistance in order to increase the μ ′ ′ dispersion of the noise suppression sheet. Therefore, using an amorphous soft magnetic alloy having a larger electrical resistance than a crystalline soft magnetic alloy is an effective means for increasing the frequency of μ ′ ′ dispersion. For example, Patent Document 3 is characterized by mainly containing flat soft magnetic particles composed of an iron-based amorphous alloy and an organic binder, and having a complex relative magnetic permeability μ ′ ′ of 7 or more at 10 GHz. electromagnetic interference suppressing body which is described here, as the soft magnetic particles, the composition formula:. {Fe a (Si x B y P z) 1-a} 100-b L b ( where, L is Al At least one element selected from Cr, Zr, Nb, Mo, Hf, Ta, W, 0.70 ≦ a ≦ 0.82 atomic%, 0 <b ≦ 8 atomic%, 0.05 ≦ x ≦ 0 .60 atomic percent, 0.10 ≦ y ≦ 0.85 atomic percent, 0.05 ≦ z ≦ 0.70 atomic percent, x + y = z = 1, particles represented by the formula: (Fe 1-a TM a) 100-w-x- y-z P w B x L y Si z ( where, TM is Co, 1 or more selected from Ni L, at least one element selected from Al, V, Cr, Y, Zr, Mo, Nb, Ta, W, 0 ≦ a ≦ 0.98 atomic percent, 2 ≦ w ≦ 16 atomic percent, 2 ≦ A particle represented by x ≦ 16 atomic percent, 0 <y ≦ 10 atomic percent, 0 ≦ z ≦ 8 atomic percent) is mentioned.
　また、特許文献４，５には、非晶質中にα－Ｆｅ結晶が析出した組織を有する軟磁性合金が記載されている。具体的には、特許文献４には、平均粒径が５～３０ｎｍのα－Ｆｅ結晶粒が析出した非晶質組織を有する、組成式：Ｆｅ１００－ａ－ｂ－ｃ－ｄＳｉａＢｂＣｃＣｕｄ（但し、１％≦ａ≦３％、９％≦ｂ≦１４％、１％≦ｃ≦４％、０．３％≦ｄ≦１．５％、８０％≦１００－ａ－ｂ－ｃ－ｄ≦８６％）で表わされる軟磁性合金が記載されている。また、特許文献５には、平均粒径が５～３０ｎｍのα－Ｆｅ結晶粒が析出した非晶質組織を有する、組成式：Ｆｅ１００－ａ－ｂ－ｃ－ｄＳｉａＰｂＣｃＣｕｄ（但し、０％≦ａ≦３％、９％≦ｂ≦１３％、４％≦ｃ≦６％、０．３％≦ｄ≦１．５％、８０％≦１００－ａ－ｂ－ｃ－ｄ≦８６％）で表わされる軟磁性合金が記載されている。そして、一例として、これらの軟磁性合金をノイズ抑制シートなどの磁性部品に適用できることが記載されている。 Patent Documents 4 and 5 disclose soft magnetic alloys having a structure in which α-Fe crystals are precipitated in an amorphous state. Specifically, Patent Document 4 discloses an amorphous structure in which α-Fe crystal grains having an average particle diameter of 5 to 30 nm are precipitated, which has a composition formula: Fe 100-a-b-c-d Si a B b C c Cu d (where, 1% ≦ a ≦ 3% , 9% ≦ b ≦ 14%, 1% ≦ c ≦ 4%, 0.3% ≦ d ≦ 1.5%, 80% ≦ 100-a A soft magnetic alloy represented by -b-c-d <86%) is described. Further, Patent Document 5 has an amorphous structure in which α-Fe crystal grains having an average particle diameter of 5 to 30 nm are precipitated, and the compositional formula: Fe 100-a-b-c-d Si a P b C c Cu d (however, 0% ≦ a ≦ 3%, 9% ≦ b ≦ 13%, 4% ≦ c ≦ 6%, 0.3% ≦ d ≦ 1.5%, 80% ≦ 100 − ab − A soft magnetic alloy represented by cd <86%) is described. And as an example, it is described that these soft-magnetic alloys can be applied to magnetic parts, such as a noise suppression sheet | seat.
特開２０１２-１８６３８４号公報JP 2012-186384 A 特開２０１３-１８２９３１号公報JP, 2013-182931, A 特開２０１５-４６５３８号公報JP, 2015-46538, A 特開２０１６-９４６５１号公報JP, 2016-94651, A 特開２０１６-９４６５２号公報Unexamined-Japanese-Patent No. 2016-94652 gazette
　近年、電子機器や通信機器の電子回路設計の高性能化および多様化が急速に進んでおり、電子回路内部のノイズの周波数も高周波化かつ広帯域化している。例えば、パソコンでは更なる高速化が求められ、ＣＰＵの駆動周波数はＭＨｚ～ＧＨｚ帯域に差し掛かっている。また、無線ＬＡＮなどの通信機器では扱うデジタルコンテンツの容量は増大しており、通信周波数もＧＨｚ帯が中心になってきている。加えて、デジタルＴＶ放送や道路交通情報システムなどの衛星通信も急速に拡大し、ユビキタスネットワーク時代が実現されつつある。このような情報通信機器の多機能化や融合が進む一方で、電子機器や通信機器から放射される余分な電波ノイズの周波数も高くなり、その電波ノイズによる機能干渉や誤動作も従来に増して心配される。そのため、従来のノイズ抑制シートは、対象帯域がｋＨｚ～ＭＨｚ帯であったのに対し、近年では、対象帯域がＭＨｚ～ＧＨｚ帯のノイズ抑制シートが求められている。 In recent years, the performance and diversification of electronic circuit designs of electronic devices and communication devices are rapidly advancing, and the frequency of noise in the electronic circuits is also increased in frequency and in a wide band. For example, in personal computers, further speeding up is required, and the drive frequency of the CPU reaches the MHz to GHz band. In addition, the capacity of digital content handled by communication devices such as wireless LANs is increasing, and the communication frequency is also centered at the GHz band. In addition, satellite communications such as digital TV broadcasting and road traffic information systems are rapidly expanding, and the ubiquitous network era is being realized. While the functions and integration of such information communication devices progress, the frequency of extra radio noise emitted from electronic devices and communication devices also increases, and functional interference and malfunction due to the radio noise are also more worrying than before. Be done. Therefore, the noise suppression sheet having the target band of MHz to GHz has been required in recent years while the conventional noise suppression sheet has the target band of kHz to MHz.
　ところが、特許文献１，２に記載のノイズ抑制シートでは、ＧＨｚ帯においては、磁性損失ではなく、誘電損失のみが作用するので、ＧＨｚ帯の電界ノイズを抑制することができたとしても、ＧＨｚ帯の磁界ノイズを抑制することはできない。電子回路では、電流回路の相互的な作用により、電界ノイズをよりも、磁界ノイズを抑制することが重要である。 However, in the noise suppression sheets described in Patent Documents 1 and 2, only the dielectric loss, not the magnetic loss, acts in the GHz band, so even if the electric field noise in the GHz band can be suppressed, the GHz band Magnetic field noise can not be suppressed. In electronic circuits, it is important to suppress magnetic field noise more than electric field noise due to the mutual action of current circuits.
　また、特許文献３に記載のノイズ抑制シートでは、μ”分散の立ち上がり周波数が１０ＭＨｚを超えたところに存在するため、１ＭＨｚ～１０ＭＨｚのノイズ抑制効果を発揮することができず、ＭＨｚからＧＨｚの広帯域に対応するノイズ抑制シートとして適していない。 Further, in the noise suppression sheet described in Patent Document 3, since the rising frequency of the μ ′ ′ dispersion is present at a position where it exceeds 10 MHz, the noise suppression effect of 1 MHz to 10 MHz can not be exhibited. It is not suitable as a noise suppression sheet corresponding to
　さらに、ノイズ抑制シートの透磁率は、合金粉末の組成の他に、ノイズ抑制シートにおける偏平状の合金粉末の配向度や充填率にも影響される。すなわち、偏平状の合金粉末は、その面内方向に磁気的異方性を有するので、ノイズ抑制シートの透磁率を高めるには、シートの面内方向における合金粉末の配向度を高める必要がある。また、ノイズ抑制シートの透磁率は、シートに含まれる合金粉末の充填率にも影響され、ノイズ抑制シートの透磁率を高めるためには、ノイズ抑制シートの密度を高める必要がある。加えて、近年、ノイズ抑制シートを使用する対象機器の性質上、難燃性のノイズ抑制シートが求められており、この対策として難燃剤を添加することが一般的である。しかしながら、難燃剤を添加すると、偏平状の合金粉末の配向度が低下してしまい、その結果、ノイズ抑制シートの透磁率が低下することによって、その周波数特性も影響を受ける。 Furthermore, the magnetic permeability of the noise suppression sheet is influenced not only by the composition of the alloy powder but also by the degree of orientation and the filling rate of the flat alloy powder in the noise suppression sheet. That is, since the flat alloy powder has magnetic anisotropy in the in-plane direction, it is necessary to increase the degree of orientation of the alloy powder in the in-plane direction of the sheet to increase the magnetic permeability of the noise suppression sheet. . The permeability of the noise suppression sheet is also influenced by the filling rate of the alloy powder contained in the sheet, and in order to increase the permeability of the noise suppression sheet, it is necessary to increase the density of the noise suppression sheet. In addition, in recent years, a flame retardant noise suppression sheet is required due to the nature of the target device using the noise suppression sheet, and it is general to add a flame retardant as a countermeasure. However, when the flame retardant is added, the degree of orientation of the flat alloy powder is lowered, and as a result, the magnetic permeability of the noise suppression sheet is lowered, and the frequency characteristics are also affected.
　ところが、特許文献４，５では、軟磁性合金の成分組成や組織を最適化することによって軟磁気特性に優れた軟磁性合金を得ることを目的としているものの、ノイズ抑制シートにおける合金粉末の配向度や、ノイズ抑制シートの密度や難燃性については記載されていない。したがって、特許文献４，５に記載の軟磁性合金を用いて、ノイズ抑制シートを作製しても、対象帯域がＭＨｚ～ＧＨｚ帯であることに加え、難燃性も併せ持つノイズ抑制シートの実現には至っていないのが現状である。 However, Patent Documents 4 and 5 aim to obtain a soft magnetic alloy excellent in soft magnetic properties by optimizing the component composition and structure of the soft magnetic alloy, but the degree of orientation of the alloy powder in the noise suppression sheet No mention is made of the density and flame retardancy of the noise suppression sheet. Therefore, even if the noise suppression sheet is produced using the soft magnetic alloys described in Patent Documents 4 and 5, in addition to the target band being the MHz to GHz band, a noise suppression sheet having not only flame resistance but also The current situation is that the
　そこで本発明は、上記課題に鑑み、ＭＨｚ～ＧＨｚ帯の広帯域における磁界ノイズに対応することができ、かつ難燃性も併せ持つ近傍界用ノイズ抑制シートを提供することを目的とする。すなわち、本発明は、μ”分散の立ち上がり周波数が１～１０ＭＨｚの帯域に存在し、かつ、μ”分散がＧＨｚ帯域まで分布していることを特徴とする難燃性の近傍界用ノイズ抑制シートを提供することを目的とする。 Accordingly, in view of the above problems, it is an object of the present invention to provide a near-field noise suppression sheet capable of coping with magnetic field noise in a wide band of MHz to GHz and also having flame retardancy. That is, according to the present invention, the flame-retardant noise suppressing sheet for the near field is characterized in that the rising frequency of the μ ′ ′ dispersion is in the band of 1 to 10 MHz and the μ ′ ′ dispersion is distributed to the GHz band. Intended to provide.
　上記課題を解決する本発明の要旨構成は以下のとおりである。
　（１）有機物からなる基材と、前記基材中に担持された偏平状の合金粉末と、前記基材中に分散した難燃剤と、を含む近傍界用ノイズ抑制シートであって、
　前記合金粉末は、原子％で、組成式：Ｆｅ１００-Ｘ１-Ｙ１（Ｓｉ，Ｐ，Ｃ）Ｘ１ＣｕＹ１（但し、１６≦Ｘ１＋Ｙ１≦２４、１４．５≦Ｘ１≦２４、及び０≦Ｙ１≦１．５）で表わされる合金粉末および／または組成式：Ｆｅ１００-Ｘ２-Ｙ２（Ｓｉ，Ｂ，Ｃ）Ｘ２ＣｕＹ２（但し、１６≦Ｘ２＋Ｙ２≦２４、１４．５≦Ｘ２≦２４、及び０≦Ｙ２≦１．５）で表わされる合金粉末であり、
　前記合金粉末の相構造は、非晶質相のみからなり、又は非晶質相とα-Ｆｅを主体とした結晶相とが混在する相からなり、
　前記難燃剤の平均粒径が１０μｍ以下であり、
　前記近傍界用ノイズ抑制シートの密度が２．５ｇ/ｃｍ３以上である
ことを特徴とする近傍界用ノイズ抑制シート。 The essential features of the present invention for solving the above-mentioned problems are as follows.
(1) A noise suppressing sheet for a near field, comprising: a base material made of an organic substance, a flat alloy powder supported in the base material, and a flame retardant dispersed in the base material,
The alloy powder has, in atomic percent, a composition formula: Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 (where 16 ≦ X 1 + Y 1 ≦ 24, 14.5 ≦ X 1 ≦ 24, and 0 ≦ Y 1 ≦ Alloy powder represented by 1.5) and / or a composition formula: Fe 100 -X 2 -Y 2 (Si, B, C) X 2 Cu Y 2 (where 16 ≦ X2 + Y 2 ≦ 24, 14.5 ≦ X 2 ≦ 24, and 0 Alloy powder represented by ≦ Y 2 ≦ 1.5),
The phase structure of the alloy powder is composed of only an amorphous phase or a mixture of an amorphous phase and a crystalline phase mainly composed of α-Fe,
The average particle size of the flame retardant is 10 μm or less,
A near-field noise suppression sheet characterized in that the density of the near-field noise suppression sheet is 2.5 g / cm 3 or more.
　（２）前記合金粉末は、１９≦Ｘ１＋Ｙ１≦２１、１８≦Ｘ１≦２１、及び０≦Ｙ１≦１．０、および／または、１９≦Ｘ２＋Ｙ２≦２１、１８≦Ｘ２≦２１、及び０≦Ｙ２≦１．０を満たす、上記（１）に記載の近傍界用ノイズ抑制シート。 (2) The alloy powder may be 19 ≦ X1 + Y1 ≦ 21, 18 ≦ X1 ≦ 21, and 0 ≦ Y1 ≦ 1.0, and / or 19 ≦ X2 + Y2 ≦ 21, 18 ≦ X2 ≦ 21, and 0 ≦ Y2 ≦ The noise suppression sheet for near fields as described in said (1) which satisfy | fills 1.0.
　（３）前記近傍界用ノイズ抑制シートのμ”分散の立ち上がりにおいて、μ”値が１以上となる周波数が１ＭＨｚ以上１０ＭＨｚ以下であり、かつ１０ＧＨｚにおけるμ”値が２以上である、上記（１）又は（２）に記載の近傍界用ノイズ抑制シート。 (3) In the rise of the μ ′ ′ dispersion of the near-field noise suppression sheet, the frequency at which the μ ′ ′ value is 1 or more is 1 MHz to 10 MHz, and the μ ′ ′ value at 10 GHz is 2 or more. Or the near-field noise suppression sheet described in (2).
　（４）前記合金粉末の保磁力が０．５Ａ/ｃｍ以上８Ａ/ｃｍ以下である、上記（１）～（３）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (4) The near-field noise suppression sheet according to any one of the above (1) to (3), wherein the coercive force of the alloy powder is 0.5 A / cm to 8 A / cm.
　（５）前記難燃剤は、水酸化アルミニウム、水酸化マグネシウム、ホウ酸亜鉛、メラミンシアネレート、及び赤リンのうちから選択される１種以上の非ハロゲン系難燃剤である、上記（１）～（４）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (5) The flame retardant is one or more non-halogen flame retardants selected from among aluminum hydroxide, magnesium hydroxide, zinc borate, melamine cyanate, and red phosphorus. The near-field noise suppression sheet according to any one of (4) to (4).
　（６）前記合金粉末において、前記Ｆｅの３原子％以下が、Ａｌ、Ｃｏ、Ｎｉ、Ｃｒ、Ｎｂ、Ｍｏ、Ｔａ、及びＷのうちから選択される１種以上の元素で置換された、上記（１）～（５）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (6) In the alloy powder, 3 atomic% or less of the Fe is substituted with one or more elements selected from Al, Co, Ni, Cr, Nb, Mo, Ta, and W. The noise suppressing sheet for near field according to any one of (1) to (5).
　（７）前記合金粉末のアスペクト比の平均値が１０以上１００以下である、上記（１）～（６）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (7) The near-field noise suppression sheet according to any one of the above (1) to (6), wherein the average value of the aspect ratio of the alloy powder is 10 or more and 100 or less.
　（８）前記合金粉末の厚さの平均値が０．１μｍ以上１．５μｍ以下である、上記（１）～（７）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (8) The near-field noise suppression sheet according to any one of the above (1) to (7), wherein the average value of the thickness of the alloy powder is 0.1 μm to 1.5 μm.
　（９）前記近傍界用ノイズ抑制シートの表面抵抗が１０５Ω/□以上である、上記（１）～（８）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (9) The near-field noise suppression sheet according to any one of the above (1) to (8), wherein the surface resistance of the near-field noise suppression sheet is 10 5 Ω / □ or more.
　（１０）前記基材はハロゲン元素を含まない、上記（１）～（９）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (10) The near-field noise suppression sheet according to any one of the above (1) to (9), wherein the base material does not contain a halogen element.
　（１１）前記ノイズ抑制シートは、シリコン系、チタン系、アルミニウム系およびジルコニウム系のうちから選択される１種以上の酸化物を含み、前記酸化物の粒径が１００ｎｍ以下である、上記（１）～（１０）のいずれか一つに記載の近傍界用ノイズ抑制シート。 (11) The above-mentioned (1), wherein the noise suppression sheet contains one or more oxides selected from silicon, titanium, aluminum and zirconium, and the particle size of the oxide is 100 nm or less. The near-field noise suppression sheet according to any one of (1) to (10).
　本発明によれば、ＭＨｚ～ＧＨｚ帯の広帯域における磁界ノイズに対応することができ、かつ難燃性を併せ持つ近傍界用ノイズ抑制シートを得ることができる。 According to the present invention, it is possible to obtain a near-field noise suppression sheet capable of coping with magnetic field noise in a broad band of MHz to GHz band and also having flame retardancy.
　以下、本発明による近傍界用ノイズ抑制シートの一実施形態について説明する。 Hereinafter, an embodiment of the near-field noise suppression sheet according to the present invention will be described.
　本発明の一実施形態による近傍界用ノイズ抑制シートは、有機物からなる基材と、基材中に担持された偏平状の合金粉末と、基材中に分散した難燃剤と、を含む。 A near-field noise suppression sheet according to an embodiment of the present invention includes a base made of an organic substance, a flat alloy powder supported in the base, and a flame retardant dispersed in the base.
　偏平状の合金粉末は、原子％で、組成式：Ｆｅ１００-Ｘ１-Ｙ１（ＳｉａＰｂＣｃ）Ｘ１ＣｕＹ１（但し、１６≦Ｘ１＋Ｙ１≦２４、１４．５≦Ｘ１≦２４、及び０≦Ｙ１≦１．５）で表わされる合金粉末および／または組成式：Ｆｅ１００-Ｘ２-Ｙ２（ＳｉｄＢｅＣｆ）Ｘ２ＣｕＹ２（但し、１６≦Ｘ２＋Ｙ２≦２４、１４．５≦Ｘ２≦２４、及び０≦Ｙ２≦１．５）で表わされる合金粉末である。ここで、ａ,ｂ,ｃ,ｄ,ｅ,ｆは、ａ＋ｂ＋ｃ＝Ｘ１、ｄ＋ｅ＋ｆ＝Ｘ２を満たす限り、特に限定されず、０≦ａ≦１０、８≦ｂ≦１９、３≦ｃ≦６、１≦ｄ≦１５、８≦ｅ≦１９、及び３≦ｆ≦６の範囲から適宜調整することができる。本明細書では、Ｆｅ１００-Ｘ１-Ｙ１（ＳｉａＰｂＣｃ）Ｘ１ＣｕＹ１をＦｅ１００-Ｘ１-Ｙ１（Ｓｉ，Ｐ，Ｃ）Ｘ１ＣｕＹ１と表記し、Ｆｅ１００-Ｘ２-Ｙ２（ＳｉｄＢｅＣｆ）Ｘ２ＣｕＹ２をＦｅ１００-Ｘ２-Ｙ２（Ｓｉ，Ｂ，Ｃ）Ｘ２ＣｕＹ２と表記する。また、Ｆｅ１００-Ｘ１-Ｙ１（Ｓｉ，Ｐ，Ｃ）Ｘ１ＣｕＹ１とＦｅ１００-Ｘ２-Ｙ２（Ｓｉ，Ｂ，Ｃ）Ｘ２ＣｕＹ２の合計量は、５０質量％以上とすることが好ましい。なお、Ｆｅ１００-Ｘ１-Ｙ１（Ｓｉ，Ｐ，Ｃ）Ｘ１ＣｕＹ１とＦｅ１００-Ｘ２-Ｙ２（Ｓｉ，Ｂ，Ｃ）Ｘ２ＣｕＹ２をともに含む場合の各合金粉末の比率は、特に限定されない。上記組成を有する合金粉末の相構造は、非晶質相のみからなる構造を有する。あるいは、これらの合金粉末のうちＣｕを含むものについては、後述する焼鈍処理を施してα-Ｆｅ結晶を析出させることによって、非晶質相とα-Ｆｅを主体とした結晶相とが混在する相とすることもできる。なお、α-Ｆｅが主体であるとは、結晶相中のα-Ｆｅの体積率が５０％以上、好ましくは７０％以上であることを意味する。 The flat alloy powder has, in atomic percent, a composition formula: Fe 100 -X 1 -Y 1 (Si a P b C c ) X 1 Cu Y 1 (where 16 ≦ X1 + Y1 ≦ 24, 14.5 ≦ X1 ≦ 24, and 0 An alloy powder represented by ≦ Y1 ≦ 1.5 and / or a composition formula: Fe 100 −X 2 −Y 2 (Si d B e C f ) X 2 Cu Y 2 (where 16 ≦ X 2 + Y 2 ≦ 24, 14.5 ≦ X 2 ≦ And an alloy powder represented by 0 ≦ Y2 ≦ 1.5). Here, a, b, c, d, e and f are not particularly limited as long as a + b + c = X1 and d + e + f = X2 are satisfied, and 0 ≦ a ≦ 10, 8 ≦ b ≦ 19, 3 ≦ c ≦ 6, It can adjust suitably from the range of 1 <= d <= 15, 8 <= e <= 19, and 3 <= f <= 6. In this specification, Fe 100 -X 1 -Y 1 (Si a P b C c ) X 1 Cu Y 1 is expressed as Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 and Fe 100 -X 2 -Y 2 Si d B e C f) X2 Cu Y2 of Fe 100-X2-Y2 (Si , denoted B, C) and X2 Cu Y2. Further, the total amount of Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 and Fe 100-X 2-Y 2 (Si, B, C) X 2 Cu Y 2 is preferably 50 mass% or more. In addition, the ratio of each alloy powder in the case where both Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 and Fe 100-X 2-Y 2 (Si, B, C) X 2 Cu Y 2 are contained is not particularly limited. . The phase structure of the alloy powder having the above composition has a structure consisting only of an amorphous phase. Alternatively, among these alloy powders, those containing Cu are mixed with an amorphous phase and a crystalline phase mainly composed of α-Fe by performing annealing treatment described later to precipitate α-Fe crystals. It can also be a matter of course. Here, that α-Fe is the main component means that the volume ratio of α-Fe in the crystal phase is 50% or more, preferably 70% or more.
　ノイズ抑制効果をより高める観点から、上記組成のＸ１，Ｘ２及びＹ１，Ｙ２は、１９≦Ｘ１＋Ｙ１≦２１、１８≦Ｘ１≦２１、及び０≦Ｙ１≦１．０、および／または、１９≦Ｘ２＋Ｙ２≦２１、１８≦Ｘ２≦２１、及び０≦Ｙ２≦１．０を満たすことが好ましい。 From the viewpoint of further enhancing the noise suppression effect, X1, X2 and Y1, Y2 of the above composition have 19 ≦ X1 + Y1 ≦ 21, 18 ≦ X1 ≦ 21, and 0 ≦ Y1 ≦ 1.0, and / or 19 ≦ X2 + Y2 ≦ It is preferable to satisfy 21, 18 ≦ X2 ≦ 21, and 0 ≦ Y2 ≦ 1.0.
　また、３原子％以下のＦｅを、Ａｌ、Ｃｏ、Ｎｉ、Ｃｒ、Ｎｂ、Ｍｏ、Ｔａ、及びＷのうちから選択される１種以上の元素で置換してもよい。ここで、置換する元素の合計の添加量が３原子％を超えると、合金粉末の飽和磁化が著しく低下することによりノイズ抑制シートの透磁率が低下する。したがって、上限値を３原子％とする。 In addition, 3 atomic% or less of Fe may be substituted with one or more elements selected from Al, Co, Ni, Cr, Nb, Mo, Ta, and W. Here, when the total addition amount of the elements to be substituted exceeds 3 atomic%, the saturation magnetization of the alloy powder is significantly reduced, whereby the magnetic permeability of the noise suppression sheet is reduced. Therefore, the upper limit value is 3 atomic%.
　以下、本実施形態によるノイズ抑制シートの製造方法の一例を示す。 Hereinafter, an example of the manufacturing method of the noise suppression sheet | seat by this embodiment is shown.
　まず、偏平状の合金粉末と、有機物と、難燃剤と、有機溶媒とを混合してスラリーを作製する。 First, a flat alloy powder, an organic matter, a flame retardant, and an organic solvent are mixed to prepare a slurry.
　合金粉末の原料粉末としては、上記の組成を有する粉末を使用し、原料粉末の形状は球形とすることが好ましい。原料粉末は、一般的な粉末の合成方法であるガスアトマイズ法または水アトマイズ法によって得ることができる。原料粉末の平均粒径は、５μｍ以上７０μｍ以下とすることが好ましい。５μｍ以上であれば、後述するアスペクト比（＝直径/厚さ）が大きな偏平状の合金粉末を容易に得ることができ、７０μｍ以下であれば、後述する偏平加工を短時間で効率的に行うことができるからである。なお、原料粉末の平均粒径は、レーザー回折・散乱法によって求めた粒度分布における積算値５０％での粒径（５０％累積粒径：Ｄ５０）を意味する。 As a raw material powder of alloy powder, it is preferable to use a powder having the above-mentioned composition, and to make the shape of the raw material powder spherical. The raw material powder can be obtained by a gas atomization method or a water atomization method which is a general powder synthesis method. The average particle size of the raw material powder is preferably 5 μm to 70 μm. If it is 5 μm or more, a flat alloy powder having a large aspect ratio (= diameter / thickness) described later can be easily obtained, and if 70 μm or less, flattening processing described later is efficiently performed in a short time Because you can do it. In addition, the average particle diameter of raw material powder means the particle diameter (50% accumulated particle diameter: D50) in 50% of the integration value in the particle size distribution calculated | required by the laser diffraction and the scattering method.
　偏平状の合金粉末は、このような球形の原料粉末を機械的に加工することによって得られる。ここで、μ”分散の立ち上がり周波数を１ＭＨｚ～１０ＭＨｚの帯域に存在させ、かつ、μ”分散をＧＨｚ帯域まで分布させるためには、偏平状の合金粉末の厚さの平均値が０．１μｍ以上１．５μｍ以下となるように偏平加工することが好ましい。また、合金粉末のアスペクト比の平均値が１０以上１００以下となるように偏平加工することが好ましい。アスペクト比の平均値が１０以上であれば、偏平状の合金粉末の面内における反磁界の影響を無視することができ、１００以下であれば、シートの面内方向における合金粉末の配向度が成膜時に高まり、平坦な表面を有するノイズ抑制シートを得ることができるからである。偏平加工には、ボールミル、アトライタ、スタンプミルなどの公知または任意の機械加工を好適に用いることができる。なお、「厚さの平均値」は、後述する方法によって作製したノイズ抑制シートの厚さ方向の断面のイオンミリング研磨面を走査型電子顕微鏡（Scanning Electron Microscope：ＳＥＭ）で観察し、視野中の１０個の粉末について、偏平状の合金粉末の厚さの値を平均した値を意味するものとし、「アスペクト比の平均値」は、同様に、ＳＥＭで観察したときの、視野中の１０個の粉末について、偏平状の合金粉末の長さ/厚さの比の値を平均した値とする。 Flat alloy powder is obtained by mechanical processing of such spherical raw material powder. Here, in order to make the rising frequency of the μ ′ ′ dispersion in the band of 1 MHz to 10 MHz and distribute the μ ′ ′ dispersion to the GHz band, the average value of the thickness of the flat alloy powder is 0.1 μm or more It is preferable to carry out flattening so as to be 1.5 μm or less. Moreover, it is preferable to carry out flat processing so that the average value of the aspect-ratio of alloy powder may be 10 or more and 100 or less. If the average value of the aspect ratio is 10 or more, the influence of the demagnetizing field in the plane of the flat alloy powder can be ignored, and if 100 or less, the degree of orientation of the alloy powder in the in-plane direction of the sheet is This is because it is possible to obtain a noise suppression sheet which is increased during film formation and has a flat surface. For flattening processing, known or arbitrary machining such as a ball mill, attritor, or stamp mill can be suitably used. The “average value of thickness” is obtained by observing the ion milling polished surface of the cross section in the thickness direction of the noise suppression sheet produced by the method described later with a scanning electron microscope (SEM) and viewing in the visual field. The mean value of the thickness of the flat alloy powder is meant for 10 powders, and the “average value of the aspect ratio” is also 10 in the field of view as observed by SEM. The value of the ratio of length / thickness of the flat alloy powder is averaged for the powder of
　次に、偏平加工の後に、合金粉末に対して窒素やアルゴンなどの不活性雰囲気中で焼鈍処理を行う。これにより、Ｃｕを含む合金粉末については、α-Ｆｅを析出させることができる。また、この焼鈍処理によって偏平加工によって合金粉末に生じた残留応力を除去することもできるので、透磁率の低下を防ぐことができる。焼鈍条件は、例えば、２００～５００℃の温度で、０．５～５時間とすることができる。このように、焼鈍条件を適宜選択して、合金粉末の相構造を制御することによって、所望の保磁力を有する合金粉末を得ることができる。合金粉末の保磁力は、０．５Ａ/ｃｍ以上８Ａ/ｃｍ以下とすることが好ましい。保磁力が０．５Ａ/ｃｍ以上であれば、μ”分散の立ち上がり周波数をＭＨｚ帯域に存在させることができ、８Ａ/ｃｍ以下であれば、ノイズを抑制するのに十分な大きさのμ”値を得ることができるからである。 Next, after flattening, the alloy powder is annealed in an inert atmosphere such as nitrogen or argon. Thereby, α-Fe can be precipitated for an alloy powder containing Cu. Moreover, since the residual stress which arose in the alloy powder by flattening is also removable by this annealing process, the fall of the magnetic permeability can be prevented. The annealing conditions may be, for example, a temperature of 200 to 500 ° C. and a time of 0.5 to 5 hours. Thus, an alloy powder having a desired coercive force can be obtained by appropriately selecting the annealing conditions and controlling the phase structure of the alloy powder. The coercive force of the alloy powder is preferably 0.5 A / cm or more and 8 A / cm or less. If the coercivity is 0.5 A / cm or more, the μ ′ ′ dispersion start frequency can be present in the MHz band, and if 8 A / cm or less, μ ′ ′ of sufficient size to suppress noise It is because a value can be obtained.
　また、絶縁処理を施すことを目的として、偏平状の合金粉末の表面に、自己酸化被膜または外部処理被膜を形成することが好ましい。被膜形成の手段や材質は、絶縁性を保つことができるのであれば、特に制限はない。被膜の厚さは２０～１００ｎｍとするのが適当であり、必要以上に被膜を形成すると磁性相の体積が減少するため、十分な大きさのμ”値を得ることができない。自己酸化被膜の形成方法としては、大気中での加熱処理または炭化水素系有機溶媒中での加熱処理が代表的な方法である。また、外部処理被膜の形成方法としては、ディップコートやＣＶＤなどの気相法が挙げられる。なお、上記の絶縁処理と焼鈍処理の順序は特に制限されない。 In addition, it is preferable to form a self-oxidized film or an externally treated film on the surface of the flat alloy powder for the purpose of applying an insulation treatment. The means and material for film formation are not particularly limited as long as they can maintain insulation. The thickness of the film is suitably 20 to 100 nm, and if the film is formed more than necessary, the volume of the magnetic phase decreases, so it is not possible to obtain a sufficiently large μ ′ ′ value. As a forming method, a heat treatment in the air or a heat treatment in a hydrocarbon-based organic solvent is a typical method, and as a method of forming an external treatment film, a vapor phase method such as dip coating or CVD. The order of the above-mentioned insulation treatment and annealing treatment is not particularly limited.
　また、偏平状の合金粉末に対して、シリコン系、チタン系、アルミニウム系およびジルコニウム系のうちから選択される１種以上のカップリング剤で表面処理を施すこともできる。カップリング処理の方法は特に限定されず、ここでは代表的な処理方法を説明する。すなわち、上記のカップリング剤を溶解した溶媒中に、偏平状の合金粉末を投入して、攪拌した後に、合金粉末を回収し、例えば１００～２００℃の温度で乾燥させる。これにより、合金粉末の表面には、粒径が１００ｎｍ以下の酸化物が形成される。このカップリング処理によって、後述する有機物との馴染み度合いが向上し、合金粉末の充填密度が高いノイズ抑制シートを得ることができ、その結果、ノイズ抑制に十分な大きさのμ”値を得ることができる。また、偏平状の合金粉末の表面に、カップリング剤に起因する絶縁酸化物の粒子が形成されるため、合金粉末の絶縁性の向上にも寄与する。 The flat alloy powder may also be surface-treated with one or more coupling agents selected from silicon, titanium, aluminum and zirconium. The method of coupling treatment is not particularly limited, and a typical treatment method will be described here. That is, the flat alloy powder is charged into a solvent in which the above-mentioned coupling agent is dissolved, and after stirring, the alloy powder is recovered and dried at a temperature of 100 to 200 ° C., for example. Thereby, an oxide having a particle size of 100 nm or less is formed on the surface of the alloy powder. By this coupling process, the degree of familiarity with an organic substance to be described later is improved, and a noise suppression sheet having a high packing density of the alloy powder can be obtained. As a result, a μ ′ ′ value large enough for noise suppression can be obtained. In addition, since particles of insulating oxide resulting from the coupling agent are formed on the surface of the flat alloy powder, it also contributes to the improvement of the insulation of the alloy powder.
　基材を構成する有機物としては、ハロゲン元素を含まないものが好ましい。これは、従来のノイズ抑制シートでは、難燃性が高い塩素化ポリエチレンなどの有機物を用いていたが、近年、ＲｏＨＳ指令等の環境規制によって、ハロゲン元素を含まないノイズ抑制シートが求められているからである。ハロゲン元素を含まない有機物としては、例えば、エポキシ樹脂、フェノール樹脂、セルロース樹脂、ポリエチレン樹脂、ポリエステル樹脂などの任意の樹脂系材料や、シリコーンゴム、アクリルゴム、ニトリルゴム、ブチルゴムなどの任意のゴム系材料や、不織布、ポリエステル繊維、アクリル繊維などの任意の繊維系材料が挙げられ、有機物の選定については目的に応じて適宜選定すればよい。これらの有機物は、結合性や可塑性の付与および合金粉末同士の絶縁隔離といった機能を有する。また、ノイズ抑制シートの柔軟性を高めるために、必要に応じてフタル酸ジオクチルなどの可塑剤を添加することもできる。 As an organic substance which comprises a base material, the thing which does not contain a halogen element is preferable. This is because, in the conventional noise suppression sheet, organic substances such as chlorinated polyethylene having high flame retardancy were used, but in recent years, a noise suppression sheet containing no halogen element is required by environmental regulations such as the RoHS directive. It is from. As an organic substance which does not contain a halogen element, for example, any resin material such as epoxy resin, phenol resin, cellulose resin, polyethylene resin, polyester resin, or any rubber material such as silicone rubber, acrylic rubber, nitrile rubber, butyl rubber Materials, and arbitrary fiber materials such as non-woven fabric, polyester fiber, acrylic fiber, etc. may be mentioned, and the selection of the organic substance may be appropriately selected according to the purpose. These organic substances have functions such as imparting of cohesion and plasticity, and isolation of alloy powders. In addition, a plasticizer such as dioctyl phthalate can be added as needed to enhance the flexibility of the noise suppression sheet.
　難燃剤については、最終的に得られるノイズ抑制シートにおけるその平均粒径を１０μｍ以下とし、好ましくは０．２μｍ以上８μｍ以下、より好ましくは０．２μｍ以上６μｍ以下とする。難燃剤は、偏平状の合金粉末間に分散して存在するので、その平均粒径が１０μｍを超えると、合金粉末のシート面内方向の配向度が著しく低下してしまう。そのため、難燃性を高めることができても、所望のノイズ抑制効果が得られない。なお、難燃剤の平均粒径が０．２μｍ以上であれば、高い難燃性を維持することができる。ここで、「難燃剤の平均粒径」とは、ノイズ抑制シートの厚さ方向の断面のイオンミリング研磨面をＳＥＭで観察したときの、視野中の１０個の難燃剤の長径の平均値を意味する。なお、難燃剤の種類は、特に限定されないが、有機物と同様にハロゲン元素を含まない難燃剤が好ましく、具体的には、水酸化アルミニウム、水酸化マグネシウム、ホウ酸亜鉛、メラミンシアネレート、及び赤リンのうちから選択される１種以上の難燃剤が挙げられる。 For the flame retardant, the average particle diameter of the finally obtained noise suppression sheet is 10 μm or less, preferably 0.2 μm to 8 μm, and more preferably 0.2 μm to 6 μm. Since the flame retardant is present dispersed in the flat alloy powder, when the average particle size exceeds 10 μm, the degree of orientation of the alloy powder in the in-plane direction of the sheet is significantly reduced. Therefore, even if the flame retardancy can be enhanced, the desired noise suppression effect can not be obtained. In addition, if the average particle diameter of a flame retardant is 0.2 micrometer or more, high flame retardance can be maintained. Here, “the average particle diameter of the flame retardant” refers to the average value of the major axes of the ten flame retardants in the field of view when the ion milling polished surface of the cross section in the thickness direction of the noise suppression sheet is observed by SEM. means. The type of the flame retardant is not particularly limited, but it is preferably a flame retardant containing no halogen element as in the organic substance, and specifically, aluminum hydroxide, magnesium hydroxide, zinc borate, melamine cyanate, and One or more flame retardants selected from red phosphorus may be mentioned.
　偏平状の合金粉末、難燃剤、及び有機物の配合比は、偏平状の合金粉末を１００質量部とした場合に、難燃剤を５質量部以上３０質量部以下、有機物を８質量部以上３０質量部以下とすることが好ましい。難燃剤が５質量部以上であれば、ＵＬ９４規格の難燃性試験においてＶ１以上となり、ノイズ抑制シートに要求される難燃性を確保することができ、３０質量部以下であれば、ノイズ抑制シート全体に対する合金粉末の体積率が著しく減少しないので、ノイズ抑制シートの透磁率が著しく低下するのを抑制することができるからである。また、有機物が８質量部以上であれば、ノイズ抑制シートの可塑性を保つことができ、３０質量部以下であれば、シート成型時に偏平状の合金粉末がシートの水平方向に配向しやすく、十分な大きさのμ”値を得ることができるからである。ここで、このような配合比で有機物を添加すれば、上述の絶縁処理を施さなくともノイズ抑制シートの表面抵抗が１０５Ω/□以上となる。なお、上述した絶縁処理を施した場合は、合金粉末自体の絶縁性が向上するため、絶縁処理を施さない場合に比べて有機物の添加量を減らすことができる。その結果、ノイズ抑制シートにおける合金粉末の体積が向上するので、透磁率が大きくなり、また難燃性も向上する。 The mixing ratio of the flat alloy powder, the flame retardant, and the organic substance is 5 parts by mass to 30 parts by mass of the flame retardant and 8 parts by mass to 30 parts of the organic substance when the flat alloy powder is 100 parts by mass. It is preferable to set it as part or less. If the flame retardant is 5 parts by mass or more, it becomes V1 or more in the flame retardancy test of UL94 standard, and the flame retardancy required for the noise suppression sheet can be secured, and if 30 parts by mass or less, the noise suppression This is because it is possible to suppress the magnetic permeability of the noise suppression sheet from being significantly reduced because the volume ratio of the alloy powder to the entire sheet is not significantly reduced. Moreover, if the organic substance is 8 parts by mass or more, the plasticity of the noise suppression sheet can be maintained, and if it is 30 parts by mass or less, the flat alloy powder is easily oriented in the horizontal direction of the sheet at the time of sheet molding. If the organic matter is added at such a compounding ratio, the surface resistance of the noise suppression sheet is 10 5 Ω / s even without the above-mentioned insulation treatment. When the above-described insulation treatment is performed, the insulation property of the alloy powder itself is improved, so that the amount of the organic substance added can be reduced as compared with the case where the insulation treatment is not performed. Since the volume of the alloy powder in the noise suppression sheet is improved, the permeability is increased and the flame retardancy is also improved.
　有機溶媒は、特に限定されず、トルエン、酢酸ブチル、酢酸エチルなどを用いることができる。なお、有機溶媒は、後続の工程で蒸発するので、ノイズ抑制シートには含まれない。 The organic solvent is not particularly limited, and toluene, butyl acetate, ethyl acetate and the like can be used. The organic solvent is not included in the noise suppression sheet because it is evaporated in the subsequent step.
　次に、スラリーの作製方法について説明する。スラリーは、公知のボールミル法によって作製することができる。すなわち、所定の配合比に調整した偏平状の合金粉末、難燃剤、有機物、及び有機溶剤を、混合および攪拌を促進するボールミルメディアとともに、容器に投入し、その容器を回転させることで、これらが均質に分散したスラリーを作製することができる。本実施形態におけるスラリーも、ボールミル法を用いて作製することは可能である。しかしながら、ボールミル法では、ボールミルメディアによって偏平状の合金粉末に大きな外力が加わり、偏平状の合金粉末の保磁力を０．５Ａ/ｃｍ以上８Ａ/ｃｍ以下の範囲内に保つことが困難になる。そのため、スラリーの作製には、ボールメディアを使用しない遊星式の混合攪拌装置を使用することが好ましい。この場合、偏平状の合金粉末に大きな外力を与えずに、偏平状の合金粉末、難燃剤、有機物、及び有機溶剤を均質に混合することが可能である。また、遊星撹拌方式であるので、スラリーに含まれる気体の脱気も促進されるので、２．５ｇ/ｃｍ３以上という高い密度を有するノイズ抑制シートを得るのに有効なスラリーを作製することができる。 Next, a method of producing a slurry will be described. The slurry can be produced by a known ball mill method. That is, flat alloy powder, flame retardant, organic substance, and organic solvent adjusted to a predetermined compounding ratio are charged into a container together with a ball mill media for promoting mixing and stirring, and these are rotated by rotating the container. A homogeneously dispersed slurry can be made. The slurry in the present embodiment can also be produced using a ball mill method. However, in the ball mill method, a large external force is applied to the flat alloy powder by the ball mill media, and it becomes difficult to keep the coercivity of the flat alloy powder in the range of 0.5 A / cm to 8 A / cm. Therefore, it is preferable to use a planetary mixing and stirring device that does not use ball media for the preparation of the slurry. In this case, the flat alloy powder, the flame retardant, the organic substance, and the organic solvent can be homogeneously mixed without giving a large external force to the flat alloy powder. In addition, since the planetary stirring system promotes degassing of the gas contained in the slurry, it is possible to produce a slurry effective for obtaining a noise suppression sheet having a high density of 2.5 g / cm 3 or more. it can.
　次に、偏平状の合金粉末、難燃剤、有機物、及び有機溶媒とからなるスラリーをドクターブレード法にてシート状に成型および乾燥して、成型体を作製する。この成型体は、偏平状の合金粉末が有機物からなる基材に担持され、かつ難燃剤が合金粉末間に分散した構造を有しており、さらに、成型時の剪段応力によって偏平状の合金粉末は互いに水平方向に配向する。ここで、ノイズ抑制シートの成型方法としては、ドクターブレード法の他にもカレンダーロール法などの公知又は任意の方法を用いることもできるが、厚さ０．１ｍｍ以下のノイズ抑制シートを作製するには、ドクターブレード法などの塗工法式を用いることが好ましい。 Next, a slurry comprising a flat alloy powder, a flame retardant, an organic substance, and an organic solvent is formed into a sheet by a doctor blade method and dried to prepare a formed body. This molded body has a structure in which a flat alloy powder is supported on a base made of an organic substance, and a flame retardant is dispersed between the alloy powders, and furthermore, a flat alloy is produced by shear stress during molding. The powders are oriented horizontally to one another. Here, as a molding method of the noise suppression sheet, in addition to the doctor blade method, a known or arbitrary method such as a calendar roll method can be used, but when producing a noise suppression sheet having a thickness of 0.1 mm or less It is preferable to use a coating method such as a doctor blade method.
　次に、偏平状の合金粉末の水平方向の配向度および密度を高めるために、シート状の成型体に対して、有機物の軟化点以上（例えば６０～１５０℃程度）に加熱した状態でプレスを施す。これにより、得られるノイズ抑制シートの厚さは、０．０５ｍｍ～０．１ｍｍ程度とすることができ、ノイズ抑制シートの密度も２．５ｇ/ｃｍ３以上にすることができる。密度が２．５ｇ/ｃｍ３未満であると、空隙が多くなり、偏平状の合金粉末の水平配向度が低下したり、シート全体に対する合金粉末の占める割合が低下したりするので、所望のノイズ抑制効果が得られない。なお、より高い透磁率を有するノイズ抑制シートとするには、ノイズ抑制シートの密度としては２．７ｇ/ｃｍ３以上にすることが好ましい。そのためには、空隙部の排除はもとより、偏平状の合金粉末の配合割合もできる限り高くして、シート全体に対する合金粉末の占める割合を高めることが有効である。 Next, in order to increase the degree of orientation and density in the horizontal direction of the flat alloy powder, the sheet-like compact is pressed in a state of being heated to a temperature higher than the softening point of the organic substance (for example, about 60 to 150 ° C.) Apply. Thereby, the thickness of the noise suppression sheet obtained can be about 0.05 mm to 0.1 mm, and the density of the noise suppression sheet can also be 2.5 g / cm 3 or more. If the density is less than 2.5 g / cm 3 , the number of voids increases, the degree of horizontal orientation of the flat alloy powder decreases, and the ratio of the alloy powder to the whole sheet decreases, so the desired noise The suppression effect can not be obtained. In order to obtain a noise suppression sheet having higher permeability, the density of the noise suppression sheet is preferably 2.7 g / cm 3 or more. For this purpose, it is effective to increase the ratio of the alloy powder to the entire sheet by increasing the proportion of the flat alloy powder as much as possible as well as eliminating the voids.
　以上の方法により、μ”分散の立ち上がり周波数が１ＭＨｚ～１０ＭＨｚの帯域に存在し、かつ、μ”分散がＧＨｚ帯域まで分布していることを特徴とする難燃性のノイズ抑制シートを得ることができる。より詳細には、かかるノイズ抑制シートでは、μ”分散の立ち上がりにおいて、μ”値が１以上となる周波数が１ＭＨz以上１０ＭＨｚ以下の帯域に存在し、かつ１０ＧＨｚでのμ”値が２以上となっている。 According to the above method, there is provided a flame retardant noise suppression sheet characterized in that the rising frequency of the μ ′ ′ dispersion is in the band of 1 MHz to 10 MHz and the μ ′ ′ dispersion is distributed to the GHz band. it can. More specifically, in the noise suppression sheet, at the rise of the μ ′ ′ dispersion, the frequency at which the μ ′ ′ value is 1 or more is present in the band of 1 MHz to 10 MHz, and the μ ′ ′ value at 10 GHz is 2 or more. ing.
　以上、本実施形態を例にして、本発明の近傍界用ノイズ抑制シートを説明したが、本発明は、上記実施形態に限定されず、特許請求の範囲において適宜変更を加えることができる。 As mentioned above, although the noise suppression sheet | seat for near fields of this invention was demonstrated taking this embodiment as an example, this invention is not limited to the said embodiment, A change can be suitably added in a claim.
　例えば、難燃剤は、スラリーを作製する際ではなく、合金粉末を偏平加工する際に予め添加してもよい。この場合、合金粉末に偏平加工を施す時に、難燃剤も粉砕および解砕されるので、添加する際の難燃剤の平均粒径が１０μｍ超えであったとしても、ノイズ抑制シートに含まれる難燃剤の平均粒径を１０μｍ以下に調整することができる。 For example, the flame retardant may be added in advance when flattening the alloy powder, not when producing a slurry. In this case, when the alloy powder is subjected to flattening processing, the flame retardant is also crushed and crushed, so the flame retardant contained in the noise suppression sheet even if the average particle size of the flame retardant when added is more than 10 μm. Can be adjusted to 10 μm or less.
（発明例１～１２、比較例１～１２）
　水アトマイズ法により、原料粉末として、表１に示す組成の合金粉末を得た。ここで、表１に示す合金粉末中のＳｉ，Ｐ，Ｃの比率は、いずれも１３：６３：２４とした。また、原料粉末の平均粒径は４０～５０μｍとした。次に、それぞれの合金粉末をアトライタにて偏平加工し、偏平状の合金粉末を得た。既述の方法によって測定した偏平状の合金粉末の厚さ及びアスペクト比の平均値を表１に示す。次に、合金粉末の表面に自己酸化被膜を形成するために、大気中にて１００℃、１時間の酸化処理を行った後に、アルゴン中で３５０～４５０℃、３０分間の焼鈍処理を行った。表１には、焼鈍処理後の各偏平状の合金粉末に対して、粉末Ｘ線回折法により測定した相構造と保磁力測定器で測定した保磁力を示す。 (Invention Examples 1 to 12, Comparative Examples 1 to 12)
An alloy powder having the composition shown in Table 1 was obtained as a raw material powder by a water atomizing method. Here, the ratio of Si, P, C in the alloy powder shown in Table 1 was 13:63:24. In addition, the average particle diameter of the raw material powder was 40 to 50 μm. Next, each alloy powder was flattened with an attritor to obtain a flat alloy powder. The average thickness and aspect ratio of the flat alloy powder measured by the method described above are shown in Table 1. Next, in order to form a self-oxidation film on the surface of the alloy powder, after performing an oxidation treatment at 100 ° C. for 1 hour in the air, an annealing treatment was performed for 30 minutes in argon at 350 to 450 ° C. . Table 1 shows the phase structure measured by powder X-ray diffractometry and the coercivity measured by the coercivity measuring device for each flat alloy powder after the annealing treatment.
　次に、偏平加工を施した各合金粉末１００質量部、ポリブチラール樹脂（軟化点：約７０℃）２０質量部、酢酸ブチル５０質量部、並びに難燃剤として水酸化マグネシウム５質量部および赤リン１質量部を、遊星式の混合撹拌装置によって混合してスラリーを作製した。なお、添加する際の難燃剤の平均粒径は、発明例１～１０並びに比較例１～４及び比較例９～１２については、水酸化マグネシウム９μｍ-赤リン７μｍ、比較例５～８については、水酸化マグネシウム１３μｍ-赤リン１３μｍとし、発明例１１については、水酸化マグネシウム８μｍ-赤リン７μｍとし、発明例１２については、水酸化マグネシウム６μｍ-赤リン６μｍとした。次に、ドクターブレード法により、ポリエチレンテレフタラートのフィルム上で、このスラリーをシート状の成型体に加工した。 Next, 100 parts by mass of each flat alloy powder, 20 parts by mass of polybutyral resin (softening point: about 70 ° C.), 50 parts by mass of butyl acetate, and 5 parts by mass of magnesium hydroxide as a flame retardant and red phosphorus 1 Parts by mass were mixed by a planetary mixing and stirring apparatus to prepare a slurry. In addition, as for the average particle diameter of the flame retardant at the time of adding, in the invention examples 1 to 10 and the comparative examples 1 to 4 and the comparative examples 9 to 12, magnesium hydroxide 9 μm-red phosphorus 7 μm and the comparative examples 5 to 8 Magnesium hydroxide was 13 μm-red phosphorus 13 μm, magnesium hydroxide 8 μm-red phosphorus 7 μm for Inventive Example 11, and magnesium hydroxide 6 μm-red phosphorus 6 μm for Inventive Example 12. Next, this slurry was processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method.
　その後、発明例１～１２及び比較例１～８については、１０ＭＰａの圧力下で１００℃、１分間の加熱プレスを施すことで、表１に示す密度を有する厚さ０．０５ｍｍのノイズ抑制シートを得た。一方、比較例９～１２については、加熱プレスを施さないで、表１に示す密度を有する厚さ０．０８ｍｍのノイズ抑制シートを得た。 Thereafter, for Inventive Examples 1 to 12 and Comparative Examples 1 to 8, a noise suppression sheet with a thickness of 0.05 mm having the density shown in Table 1 by applying a heat press at 100 ° C. for 1 minute under a pressure of 10 MPa. I got On the other hand, in Comparative Examples 9 to 12, a noise suppression sheet with a thickness of 0.08 mm having the density shown in Table 1 was obtained without heat pressing.
　各発明例および比較例のノイズ抑制シートについて、ネットワークアナライザを用いたＳパラメータ法によって透磁率特性を測定した。μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数、および１０ＧＨｚにおけるμ”値の大きさを表１に示す。 The permeability characteristics of the noise suppression sheets of the invention examples and the comparative examples were measured by the S-parameter method using a network analyzer. Table 1 shows the frequency at which the μ ′ ′ value becomes 1 or more and the magnitude of the μ ′ ′ value at 10 GHz when the μ ′ ′ dispersion starts to rise.
　また、各発明例および比較例のノイズ抑制シートについて、既述の方法で測定した難燃剤の平均粒径、アルキメデス法によって測定した密度、およびハイレスタにて測定した表面抵抗を表１に示す。 Moreover, about the noise suppression sheet | seat of each invention example and a comparative example, the average particle diameter of the flame retardant measured by the method as stated above, the density measured by the Archimedes method, and the surface resistance measured by the high rester are shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　発明例１～１２では、本発明の成分組成を満足し、難燃剤の平均粒径が１０μｍ以下、ノイズ抑制シートの密度が２．５ｇ/ｃｍ３以上であったので、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数は１～１０ＭＨｚの範囲内に存在し、１０ＧＨｚにおけるμ”値は２を超えていた。特に、発明例２，３，１１，１２では、磁気特性が良好であるせいか、１０ＧＨｚにおけるμ”値は４．５を超えていた。一方、比較例１，２では、１０ＧＨｚにおけるμ”値は２未満であった。比較例１では、Ｆｅ濃度が低いために、偏平状の合金粉末の磁束密度も小さくなり、１０ＧＨｚにおけるμ”値は２未満であったと考えられる。また、比較例２では、本発明の成分組成を満足しておらず、偏平状の合金粉末の保磁力が８Ａ/ｃｍを超えているため、軟磁気特性が低下し、１０ＧＨｚにおけるμ”値は２未満であったと考えられる。また、Ｃｕが１．５原子％を超える比較例３、４では、Ｘ線回折測定によって磁気異方性が大きいＦｅＰ化合物が形成されていることがわかった。その結果、保磁力が８Ａ/ｃｍを超えており、周波数に対するμ”の分布幅は狭く、１０ＧＨｚにおけるμ”値も０．０であった。なお、アスペクト比については、１０以上であれば、透磁率の特性への影響はほとんど無視できると考えられる。また、１０ＧＨzにおけるμ”値が２以上あれば、軽薄短小化および高周波化する近年の電子機器などにおいて発生するノイズを効果的に抑制させることができる。 In the invention examples 1 to 12, the component composition of the present invention is satisfied, the average particle diameter of the flame retardant is 10 μm or less, and the density of the noise suppression sheet is 2.5 g / cm 3 or more. The frequency at which the value of μ ′ ′ is 1 or more is in the range of 1 to 10 MHz, and the value of μ ′ ′ at 10 GHz exceeds 2. Especially, in the invention examples 2, 3, 11 and 12, the magnetic characteristics are Possibly good, the μ ′ ′ value at 10 GHz was above 4.5. On the other hand, in Comparative Examples 1 and 2, the μ ′ ′ value at 10 GHz was less than 2. In Comparative Example 1, the magnetic flux density of the flat alloy powder also decreased due to the low Fe concentration, and the μ ′ ′ value at 10 GHz Is considered to be less than two. Further, in Comparative Example 2, the component composition of the present invention is not satisfied, and since the coercive force of the flat alloy powder exceeds 8 A / cm, the soft magnetic characteristics are degraded, and the μ ′ ′ value at 10 GHz is It is considered that it was less than 2. Further, in Comparative Examples 3 and 4 in which Cu exceeds 1.5 atomic%, it was found by X-ray diffraction measurement that a FeP compound having large magnetic anisotropy was formed. As a result, the coercivity exceeded 8 A / cm, the distribution width of μ ′ ′ with respect to the frequency was narrow, and the μ ′ ′ value at 10 GHz was also 0.0. If the μ ′ ′ value at 10 GHz is 2 or more, it is possible to effectively suppress the noise generated in recent electronic devices that are reduced in size, size, size, and frequency, if the μ ′s value at 10 GHz is 2 or more. It can be.
　比較例５～８では、難燃剤の平均粒径が１０μｍを超えており、ＳＥＭ観察から合金粉末のシート面内の配向性が乱れている部分が随所に確認された。そのため、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数は１０ＭＨｚを超えており、１０ＧＨｚにおけるμ”値も２を下回っていた。 In Comparative Examples 5 to 8, the average particle diameter of the flame retardant was more than 10 μm, and from the observation with SEM, a part where the in-plane orientation of the alloy powder was disturbed was confirmed everywhere. Therefore, at the beginning of the rise of the μ ′ ′ dispersion, the frequency at which the μ ′ ′ value is 1 or more exceeded 10 MHz, and the μ ′ ′ value at 10 GHz was also below 2.
　比較例９～１２では、ノイズ抑制シートの密度が２．５ｇ/ｃｍ３を下回っており、ＳＥＭ観察から合金粉末のシート面内の配向性が乱れている部分が随所に確認された。そのため、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数は１０ＭＨｚを超えており、１０ＧＨｚにおけるμ”値も２を下回っていた。 In Comparative Examples 9 to 12, the density of the noise suppression sheet was less than 2.5 g / cm 3, and it was confirmed by SEM observation everywhere that the orientation in the sheet plane of the alloy powder was disturbed. Therefore, at the beginning of the rise of the μ ′ ′ dispersion, the frequency at which the μ ′ ′ value is 1 or more exceeded 10 MHz, and the μ ′ ′ value at 10 GHz was also below 2.
発明例１１，１２では、難燃剤の平均粒径が８μｍ以下であり、ノイズ抑制シートの密度が２．７ｇ/ｃｍ３以上であったので、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数が１～１０ＭＨｚの範囲内に存在し、１０ＧＨｚにおけるμ”値は５を超えていた。これらのシートでは、難燃剤の平均粒径が小さくなるほど偏平粉末のシート面内の配向性が良好になり、そのために１０ＧＨｚにおけるμ”値もより大きくなった。 In the invention examples 11 and 12, the average particle diameter of the flame retardant is 8 μm or less, and the density of the noise suppression sheet is 2.7 g / cm 3 or more. The above frequency is in the range of 1 to 10 MHz, and the μ ′ ′ value at 10 GHz exceeds 5. In these sheets, the in-plane orientation of the flat powder sheet as the average particle diameter of the flame retardant decreases. Becomes better, so that the μ ′ ′ value at 10 GHz also becomes larger.
（発明例１３～２４、比較例１３～２４）
　水アトマイズ法により、原料粉末として、表２に示す組成の合金粉末を得た。ここで、表２に示す合金粉末中のＳｉ，Ｂ，Ｃの比率は、いずれも１３：６３：２４とした。また、原料粉末の平均粒径は４０～５０μｍとした。次に、それぞれの合金粉末をアトライタにて偏平加工し、偏平状の合金粉末を得た。既述の方法によって測定した偏平状の合金粉末の厚さ及びアスペクト比の平均値を表２に示す。次に、シランカップリング剤として３-アミノプロピルトリエトキシシランが２質量％添加されているエタノール溶液中に合金粉末を投入し、３０分間の攪拌を行った。その後、粉末を溶液中から取り出し、大気中で１５０℃、８時間の条件で乾燥させた。その後、窒素中で３５０～４５０℃、３０分間の焼鈍処理を行った。表２には、既述の方法によって測定した相構造と保磁力を示す。 (Inventive Examples 13 to 24, Comparative Examples 13 to 24)
An alloy powder of the composition shown in Table 2 was obtained as a raw material powder by a water atomization method. Here, the ratio of Si, B and C in the alloy powder shown in Table 2 was 13:63:24. In addition, the average particle diameter of the raw material powder was 40 to 50 μm. Next, each alloy powder was flattened with an attritor to obtain a flat alloy powder. The average thickness and aspect ratio of the flat alloy powder measured by the method described above are shown in Table 2. Next, the alloy powder was charged into an ethanol solution to which 2% by mass of 3-aminopropyltriethoxysilane was added as a silane coupling agent, and stirring was performed for 30 minutes. Thereafter, the powder was taken out of the solution and dried in the atmosphere at 150 ° C. for 8 hours. Thereafter, annealing was performed in nitrogen at 350 to 450 ° C. for 30 minutes. Table 2 shows the phase structure and the coercivity measured by the method described above.
　次に、偏平加工を施した各合金粉末１００質量部、アクリルゴム２０質量部（軟化点：約７０℃）、トルエン５０質量部、並びに難燃剤としてメラミンシアヌレート５質量部及び赤リン１質量部を、遊星式の混合撹拌装置によって混合してスラリーを作製した。なお、添加する際の難燃剤の平均粒径は、発明例１３～２２並びに比較例１３～１６及び２１～２４については、水酸化マグネシウム９μｍ-赤リン７μｍとし、比較例１７～２０については、水酸化マグネシウム１３μｍ-赤リン１３μｍとし、発明例２３については、水酸マグネシウム８μｍ-赤リン７μｍとし、発明例２４については、水酸化マグネシウム６μｍ-赤リン６μｍとした。次に、ドクターブレード法により、ポリエチレンテレフタラートのフィルム上で、このスラリーをシート状の成型体に加工した。 Next, 100 parts by mass of each flat alloy powder, 20 parts by mass of acrylic rubber (softening point: about 70 ° C.), 50 parts by mass of toluene, and 5 parts by mass of melamine cyanurate as a flame retardant and 1 part by mass of red phosphorus Were mixed by a planetary mixing and stirring apparatus to prepare a slurry. In addition, the average particle diameter of the flame retardant at the time of adding is set to magnesium hydroxide 9 μm-red phosphorus 7 μm for Inventive Examples 13 to 22 and Comparative Examples 13 to 16 and 21 to 24, and Comparative Examples 17 to 20. Magnesium hydroxide was 13 μm-red phosphorus 13 μm, magnesium hydroxide 8 μm-red phosphorus 7 μm for invention example 23, magnesium hydroxide 6 μm-red phosphorus 6 μm for invention example 24. Next, this slurry was processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method.
　その後、発明例１３～２４及び比較例１３～２０については、１０ＭＰａの圧力下で１００℃、１分間の加熱プレスを施すことで、表２に示す密度を有する厚さ０．０５ｍｍのノイズ抑制シートを作製した。一方、比較例２１～２４については、加熱プレスを施さないで、表２に示す密度を有する厚さ０．０８ｍｍのノイズ抑制シートを得た。 Thereafter, for Inventive Examples 13 to 24 and Comparative Examples 13 to 20, by applying a heat press at 100 ° C. for 1 minute under a pressure of 10 MPa, a noise suppression sheet with a thickness shown in Table 2 and a thickness of 0.05 mm. Was produced. On the other hand, in Comparative Examples 21 to 24, a noise suppression sheet with a thickness of 0.08 mm having the density shown in Table 2 was obtained without heat pressing.
　各発明例および比較例について、既述の方法で、透磁率特性、難燃剤の平均粒径、ノイズ抑制シートの密度、および表面抵抗を測定した。測定結果を表２に示す。 The permeability characteristics, the average particle diameter of the flame retardant, the density of the noise suppression sheet, and the surface resistance were measured by the methods described above for each of the invention examples and the comparative examples. The measurement results are shown in Table 2.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　発明例１３～２４では、難燃剤の平均粒径が１０μｍ以下であり、ノイズ抑制シートの密度が２．５ｇ/ｃｍ３以上であったので、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数が１～１０ＭＨｚの範囲内に存在し、１０ＧＨｚにおけるμ”値は２を超えていた。特に、発明例１４，１５,２３，２４では、磁気特性が良好であるせいか、１０ＧＨｚにおけるμ”値は４．５を超えていた。一方、比較例１３，１４では、１０ＧＨｚにおけるμ”値は２未満であった。比較例１３では、Ｆｅ濃度が低いために、偏平状の合金粉末の磁束密度も小さくなり、１０ＧＨｚにおけるμ”値が２未満になったと考えられる。また、比較例１４では、本発明の成分組成を満足しておらず、偏平状の合金粉末の保磁力が８Ａ/ｃｍを超えているため、軟磁気特性が低下し、１０ＧＨｚにおけるμ”値は２未満であったと考えられる。また、Ｃｕが１．５原子％を超える比較例１５，１６では、Ｘ線回折測定によって、磁気異方性が大きいＦｅＢの化合物が形成されていることがわかった。その結果、保磁力が８Ａ/ｃｍを超えており、周波数に対するμ”の分布幅は狭く、１０ＧＨｚにおけるμ”値も０．０であった。 In the invention examples 13 to 24, since the average particle size of the flame retardant is 10 μm or less and the density of the noise suppression sheet is 2.5 g / cm 3 or more, the μ ′ ′ value starts to rise, μ ′ ′ value is 1 The above frequency is in the range of 1 to 10 MHz, and the μ ′ ′ value at 10 GHz exceeds 2. Especially in the invention examples 14, 15, 23, 24 it may be because the magnetic characteristics are good, 10 GHz. The value of μ "at was over 4.5. On the other hand, in Comparative Examples 13 and 14, the μ ′ ′ value at 10 GHz was less than 2. In Comparative Example 13, the magnetic flux density of the flat alloy powder also decreased due to the low Fe concentration, and the μ ′ ′ value at 10 GHz Is considered to be less than 2. Further, in Comparative Example 14, the component composition of the present invention is not satisfied, and since the coercive force of the flat alloy powder exceeds 8 A / cm, the soft magnetic characteristics are degraded, and the μ ′ ′ value at 10 GHz is It is considered that it was less than 2. Further, in Comparative Examples 15 and 16 in which Cu exceeds 1.5 atomic%, it was found by X-ray diffraction measurement that a compound of FeB having large magnetic anisotropy was formed. As a result, the coercive force exceeded 8 A / cm, the distribution width of μ ′ ′ with respect to frequency was narrow, and the μ ′ ′ value at 10 GHz was also 0.0.
　比較例１７～２０では、難燃剤の平均粒径が１０μｍを超えており、ＳＥＭ観察から合金粉末のシート面内の配向性が乱れている部分が随所に確認された。そのため、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数は１０ＭＨｚを超えており、１０ＧＨｚにおけるμ”値も２を下回っていた。 In Comparative Examples 17 to 20, the average particle diameter of the flame retardant was more than 10 μm, and from the observation with SEM, a portion in which the in-plane orientation of the alloy powder was disturbed was confirmed everywhere. Therefore, at the beginning of the rise of the μ ′ ′ dispersion, the frequency at which the μ ′ ′ value is 1 or more exceeded 10 MHz, and the μ ′ ′ value at 10 GHz was also below 2.
　比較例２１～２４では、ノイズ抑制シートの密度が２．５ｇ/ｃｍ３を下回っており、ＳＥＭ観察から合金粉末のシート面内の配向性が乱れている部分が随所に確認された。そのため、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数は１０ＭＨｚを超えており、１０ＧＨｚにおけるμ”値も２を下回っていた。 In Comparative Examples 21 to 24, the density of the noise suppression sheet was less than 2.5 g / cm 3 , and SEM observation confirmed everywhere that the orientation in the sheet surface of the alloy powder was disturbed. Therefore, at the beginning of the rise of the μ ′ ′ dispersion, the frequency at which the μ ′ ′ value is 1 or more exceeded 10 MHz, and the μ ′ ′ value at 10 GHz was also below 2.
　発明例２３，２４では、難燃剤の平均粒径が８μｍ以下であり、ノイズ抑制シートの密度が２．７ｇ/ｃｍ３以上であったので、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数が１～１０ＭＨｚの範囲内に存在し、１０ＧＨｚにおけるμ”値は５を超えていた。これらのシートでは、難燃剤の平均粒径が小さくなるほど偏平粉末のシート面内の配向性が良好になり、そのために１０ＧＨｚにおけるμ”値もより大きくなった。 In the invention examples 23 and 24, since the average particle diameter of the flame retardant is 8 μm or less and the density of the noise suppression sheet is 2.7 g / cm 3 or more, the μ ′ ′ value starts to rise, and the μ ′ ′ value is 1 The above frequency is in the range of 1 to 10 MHz, and the μ ′ ′ value at 10 GHz exceeds 5. In these sheets, the in-plane orientation of the flat powder sheet as the average particle diameter of the flame retardant decreases. Becomes better, so that the μ ′ ′ value at 10 GHz also becomes larger.
（発明例２５～２７）
　水アトマイズ法により、原料粉末として、表３に示す組成の合金粉末を得た。ここで、表３に示す合金粉末中のＳｉ，Ｂ，Ｃ及びＳｉ，Ｐ，Ｃの比率は、いずれも９：６５：２６とし、各発明例２５～２７における２種類の合金粉末の混合比は１：１とした。また、原料粉末の平均粒径は４０～５０μｍとした。次に、それぞれの合金粉末をアトライタにて偏平加工し、偏平状の合金粉末を得た。既述の方法によって測定した偏平状の合金粉末の厚さ及びアスペクト比の平均値を表３に示す。次に、合金粉末の表面に自己酸化被膜を形成するために、大気中にて１００℃、１時間の酸化処理を行った後に、アルゴン中で３５０～４５０℃、３０分間の焼鈍処理を行った。表３には、既述の方法によって測定した相構造と保磁力測定器で測定した保磁力を示す。 Invention Examples 25 to 27
An alloy powder having the composition shown in Table 3 was obtained as a raw material powder by a water atomizing method. Here, the ratio of Si, B, C and Si, P, C in the alloy powder shown in Table 3 is 9:65:26, and the mixing ratio of the two types of alloy powder in each of Inventive Examples 25 to 27. Is 1: 1. In addition, the average particle diameter of the raw material powder was 40 to 50 μm. Next, each alloy powder was flattened with an attritor to obtain a flat alloy powder. The average thickness and aspect ratio of the flat alloy powder measured by the method described above are shown in Table 3. Next, in order to form a self-oxidation film on the surface of the alloy powder, after performing an oxidation treatment at 100 ° C. for 1 hour in the air, an annealing treatment was performed for 30 minutes in argon at 350 to 450 ° C. . Table 3 shows the phase structure measured by the method described above and the coercivity measured by the coercivity meter.
　次に、偏平加工を施した各合金粉末１００質量部、ポリブチラール樹脂（軟化点：約７０℃）２０質量部、酢酸ブチル５０質量部、並びに難燃剤として平均粒径が８μｍの水酸化マグネシウム５質量部および平均粒径が８μｍの赤リン１質量部を、遊星式の混合撹拌装置によって混合してスラリーを作製した（発明例２５）。また、偏平加工を施した各合金粉末１００質量部、ポリブチラール樹脂（軟化点：約７０℃）２０質量部、酢酸ブチル５０質量部、並びに難燃剤として平均粒径が６μｍの水酸化マグネシウム５質量部および平均粒径が６μｍの赤リン１質量部を、遊星式の混合撹拌装置によって混合してスラリーを作製した（発明例２６，２７）。次に、ドクターブレード法により、ポリエチレンテレフタラートのフィルム上で、これらのスラリーをシート状の成型体に加工した。その後、１０ＭＰａの圧力下で１００℃、１分間の加熱プレスを施すことで、厚さ０．０５ｍｍのノイズ抑制シートを作製した。 Next, 100 parts by mass of each flat alloy powder, 20 parts by mass of polybutyral resin (softening point: about 70 ° C.), 50 parts by mass of butyl acetate, and magnesium hydroxide 5 having an average particle diameter of 8 μm as a flame retardant A part by mass and 1 part by mass of red phosphorus having an average particle diameter of 8 μm were mixed by a planetary mixing and stirring device to prepare a slurry (Inventive Example 25). In addition, 100 parts by mass of each flat alloy powder, 20 parts by mass of polybutyral resin (softening point: about 70 ° C.), 50 parts by mass of butyl acetate, and 5 parts by mass of magnesium hydroxide having an average particle diameter of 6 μm as a flame retardant Parts and 1 part by mass of red phosphorus having an average particle diameter of 6 μm were mixed by a planetary mixing and stirring apparatus to prepare a slurry (Inventive Examples 26 and 27). Next, these slurries were processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method. Then, the noise suppression sheet | seat of thickness 0.05 mm was produced by giving the heating press of 100 degreeC and 1 minute under the pressure of 10 Mpa.
　各発明例について、既述の方法で、透磁率特性、難燃剤の平均粒径、ノイズ抑制シートの密度、および表面抵抗を測定した。測定結果を表３に示す。 The permeability characteristics, the average particle size of the flame retardant, the density of the noise suppression sheet, and the surface resistance were measured for each invention example by the method described above. The measurement results are shown in Table 3.
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　発明例２５～２７では、難燃剤の平均粒径が８μｍ以下であり、ノイズ抑制シートの密度が２．７ｇ/ｃｍ３以上であったので、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数が１～１０ＭＨｚの範囲内に存在し、１０ＧＨｚにおけるμ”値は２を超えていた。特に、難燃剤の平均粒径が６μｍ以下であった発明例２６，２７は、偏平粉末のシート面内の配向性が更に良好となり、１０ＧＨｚにおけるμ”値は５を超えていた。 In the invention examples 25 to 27, the average particle diameter of the flame retardant is 8 μm or less, and the density of the noise suppression sheet is 2.7 g / cm 3 or more. The frequency of the above was in the range of 1 to 10 MHz, and the μ ′ ′ value at 10 GHz exceeded 2. Especially in the invention examples 26 and 27 in which the average particle diameter of the flame retardant was 6 μm or less, the flat powder Orientation in the sheet plane was further improved, and the μ ′ ′ value at 10 GHz exceeded 5.
（発明例２８～３５）
　水アトマイズ法により、原料粉末として、表４に示す組成の合金粉末を得た。ここで、表４に示す合金粉末中のＳｉ，Ｂ，Ｃ及びＳｉ，Ｐ，Ｃの比率は、いずれも９：６５：２６とした。また、原料粉末の平均粒径は４０～５０μｍとした。次に、それぞれの合金粉末をアトライタにて偏平加工し、偏平状の合金粉末を得た。既述の方法によって測定した偏平状の合金粉末の厚さ及びアスペクト比の平均値を表４に示す。次に、チタン系のカップリング剤としてテトラノルマルブチルチタネートを２質量％添加したエタノール溶液中に合金粉末を投入し、３０分間の攪拌を行った。その後、合金粉末を溶液中から取り出し、大気中で１５０℃、８時間の条件で乾燥させ、合金粉末の表面に、平均粒径が１００ｎｍ以下の酸化物を形成した。その後、窒素中で３５０～４５０℃、３０分間の焼鈍処理を行った。表４には、既述の方法によって測定した相構造と保磁力を示す。 Invention Examples 28 to 35
An alloy powder having the composition shown in Table 4 was obtained as a raw material powder by a water atomizing method. Here, the ratio of Si, B, C and Si, P, C in the alloy powder shown in Table 4 was 9:65:26. In addition, the average particle diameter of the raw material powder was 40 to 50 μm. Next, each alloy powder was flattened with an attritor to obtain a flat alloy powder. The average thickness and aspect ratio of the flat alloy powder measured by the method described above are shown in Table 4. Next, the alloy powder was put into an ethanol solution to which 2% by mass of tetranormal butyl titanate was added as a titanium-based coupling agent, and stirring was performed for 30 minutes. Thereafter, the alloy powder was taken out of the solution and dried in the atmosphere at 150 ° C. for 8 hours to form an oxide having an average particle diameter of 100 nm or less on the surface of the alloy powder. Thereafter, annealing was performed in nitrogen at 350 to 450 ° C. for 30 minutes. Table 4 shows the phase structure and the coercivity measured by the method described above.
　次に、偏平加工を施した各合金粉末１００質量部、アクリルゴム２０質量部（軟化点：約７０℃）、トルエン５０質量部、並びに難燃剤として平均粒径が１０μｍのメラミンシアヌレート５質量部及び平均粒径が１０μｍの赤リン１質量部を、遊星式の混合撹拌装置によって混合してスラリーを作製した。次に、ドクターブレード法により、ポリエチレンテレフタラートのフィルム上で、このスラリーをシート状の成型体に加工した。その後、１０ＭＰａの圧力下で１００℃、１分間の加熱プレスを施すことで、表４に示す密度を有する厚さ０．０５ｍｍのノイズ抑制シートを作製した。 Next, 100 parts by mass of each flat alloy powder, 20 parts by mass of acrylic rubber (softening point: about 70 ° C.), 50 parts by mass of toluene, and 5 parts by mass of melamine cyanurate having an average particle diameter of 10 μm as a flame retardant And 1 part by mass of red phosphorus having an average particle diameter of 10 μm was mixed by a planetary mixing and stirring apparatus to prepare a slurry. Next, this slurry was processed into a sheet-like molded body on a polyethylene terephthalate film by a doctor blade method. Thereafter, a heat suppression was performed at 100 ° C. for 1 minute under a pressure of 10 MPa to produce a noise suppression sheet having a density shown in Table 4 and a thickness of 0.05 mm.
　各発明例について、既述の方法で、透磁率特性、難燃剤の平均粒径、ノイズ抑制シートの密度、および表面抵抗を測定した。測定結果を表４に示す。 The permeability characteristics, the average particle size of the flame retardant, the density of the noise suppression sheet, and the surface resistance were measured for each invention example by the method described above. The measurement results are shown in Table 4.
Figure JPOXMLDOC01-appb-T000004
Figure JPOXMLDOC01-appb-T000004
　発明例２８～３５では、難燃剤の平均粒径が１０μｍ以下であり、ノイズ抑制シートの密度が２．５ｇ/ｃｍ３以上であったので、μ”分散の立ち上がりはじめで、μ”値が１以上となる周波数が１～１０ＭＨｚの範囲内に存在し、１０ＧＨｚにおけるμ”値は２を超えていた。Ｆｅに対するＡｌ、Ｃｏ、Ｎｉ、Ｃｒ、Ｎｂ、Ｍｏ、Ｔａ、Ｗの置換量の合計が３原子％以下の発明例２８，３０，３２，３４は、１０ＧＨｚにおけるμ”値が２．５以上の高い値となっていた。これは、Ｆｅに対するＡｌ、Ｃｏ、Ｎｉ、Ｃｒ、Ｎｂ、Ｍｏ、Ｔａ、Ｗの置換量の合計が３原子％を超えたものは、合金粉末の磁束密度が小さくなったことが考えられ、Ｆｅに対するＡｌ、Ｃｏ、Ｎｉ、Ｃｒ、Ｎｂ、Ｍｏ、Ｔａ、Ｗの置換量の合計は３原子％以下とするのがより好ましい。 In the invention examples 28 to 35, since the average particle size of the flame retardant is 10 μm or less and the density of the noise suppression sheet is 2.5 g / cm 3 or more, the μ ′ ′ value starts to rise, μ ′ ′ value is 1 The above frequency is in the range of 1 to 10 MHz, and the μ ′ ′ value at 10 GHz is more than 2. The total substitution amount of Al, Co, Ni, Cr, Nb, Mo, Ta, W to Fe is In the invention examples 28, 30, 32, 34 of 3 atomic% or less, the μ ′ ′ value at 10 GHz was a high value of 2.5 or more. It is considered that the magnetic flux density of the alloy powder is reduced when the total of the substitution amounts of Al, Co, Ni, Cr, Nb, Mo, Ta, W with respect to Fe exceeds 3 atomic%, More preferably, the total of the substitutional amounts of Al, Co, Ni, Cr, Nb, Mo, Ta and W with respect to is 3 atomic% or less.
　本発明によれば、ＭＨｚ～ＧＨｚ帯の広帯域における磁界ノイズに対応することができ、かつ難燃性を併せ持つ近傍界用ノイズ抑制シートを得ることができる。 According to the present invention, it is possible to obtain a near-field noise suppression sheet capable of coping with magnetic field noise in a broad band of MHz to GHz band and also having flame retardancy.

Claims (11)

  1. 　有機物からなる基材と、前記基材中に担持された偏平状の合金粉末と、前記基材中に分散した難燃剤と、を含む近傍界用ノイズ抑制シートであって、
    　前記合金粉末は、原子％で、組成式：Ｆｅ１００-Ｘ１-Ｙ１（Ｓｉ，Ｐ，Ｃ）Ｘ１ＣｕＹ１（但し、１６≦Ｘ１＋Ｙ１≦２４、１４．５≦Ｘ１≦２４、及び０≦Ｙ１≦１．５）で表わされる合金粉末および／または組成式：Ｆｅ１００-Ｘ２-Ｙ２（Ｓｉ，Ｂ，Ｃ）Ｘ２ＣｕＹ２（但し、１６≦Ｘ２＋Ｙ２≦２４、１４．５≦Ｘ２≦２４、及び０≦Ｙ２≦１．５）で表わされる合金粉末であり、
    　前記合金粉末の相構造は、非晶質相のみからなり、又は非晶質相とα-Ｆｅを主体とした結晶相とが混在する相からなり、
    　前記難燃剤の平均粒径が１０μｍ以下であり、
    　前記近傍界用ノイズ抑制シートの密度が２．５ｇ/ｃｍ３以上である
    ことを特徴とする近傍界用ノイズ抑制シート。     A noise suppressing sheet for a near field, comprising a base made of an organic substance, a flat alloy powder carried in the base, and a flame retardant dispersed in the base,
    The alloy powder has, in atomic percent, a composition formula: Fe 100 -X 1 -Y 1 (Si, P, C) X 1 Cu Y 1 (where 16 ≦ X 1 + Y 1 ≦ 24, 14.5 ≦ X 1 ≦ 24, and 0 ≦ Y 1 ≦ Alloy powder represented by 1.5) and / or a composition formula: Fe 100 -X 2 -Y 2 (Si, B, C) X 2 Cu Y 2 (where 16 ≦ X2 + Y 2 ≦ 24, 14.5 ≦ X 2 ≦ 24, and 0 Alloy powder represented by ≦ Y 2 ≦ 1.5),
    The phase structure of the alloy powder is composed of only an amorphous phase or a mixture of an amorphous phase and a crystalline phase mainly composed of α-Fe,
    The average particle size of the flame retardant is 10 μm or less,
    A near-field noise suppression sheet characterized in that the density of the near-field noise suppression sheet is 2.5 g / cm 3 or more.
  2. 　前記合金粉末は、１９≦Ｘ１＋Ｙ１≦２１、１８≦Ｘ１≦２１、及び０≦Ｙ１≦１．０、および／または、１９≦Ｘ２＋Ｙ２≦２１、１８≦Ｘ２≦２１、及び０≦Ｙ２≦１．０を満たす、請求項１に記載の近傍界用ノイズ抑制シート。 The alloy powder has 19 ≦ X1 + Y1 ≦ 21, 18 ≦ X1 ≦ 21, and 0 ≦ Y1 ≦ 1.0, and / or 19 ≦ X2 + Y2 ≦ 21, 18 ≦ X2 ≦ 21, and 0 ≦ Y2 ≦ 1.0. The near-field noise suppression sheet according to claim 1, wherein
  3. 　前記近傍界用ノイズ抑制シートのμ”分散の立ち上がりにおいて、μ”値が１以上となる周波数が１ＭＨｚ以上１０ＭＨｚ以下であり、かつ１０ＧＨｚにおけるμ”値が２以上である、請求項１又は２に記載の近傍界用ノイズ抑制シート。 3. The frequency at which the μ ′ ′ value is 1 or more is 1 MHz or more and 10 MHz or less, and the μ ′ ′ value at 10 GHz is 2 or more at the rise of the μ ′ ′ dispersion of the near-field noise suppression sheet. Noise suppression sheet for near field described.
  4. 　前記合金粉末の保磁力が０．５Ａ/ｃｍ以上８Ａ/ｃｍ以下である、請求項１～３のいずれか一項に記載の近傍界用ノイズ抑制シート。 The near-field noise suppression sheet according to any one of claims 1 to 3, wherein the coercive force of the alloy powder is 0.5 A / cm or more and 8 A / cm or less.
  5. 　前記難燃剤は、水酸化アルミニウム、水酸化マグネシウム、ホウ酸亜鉛、メラミンシアネレート、及び赤リンのうちから選択される１種以上の非ハロゲン系難燃剤である、請求項１～４のいずれか一項に記載の近傍界用ノイズ抑制シート。 The flame retardant according to any one of claims 1 to 4, wherein the flame retardant is at least one non-halogen flame retardant selected from among aluminum hydroxide, magnesium hydroxide, zinc borate, melamine cyanate and red phosphorus. The noise suppression sheet for near fields as described in 1 or 2.
  6. 　前記合金粉末において、前記Ｆｅの３原子％以下が、Ａｌ、Ｃｏ、Ｎｉ、Ｃｒ、Ｎｂ、Ｍｏ、Ｔａ、及びＷのうちから選択される１種以上の元素で置換された、請求項１～５のいずれか一項に記載の近傍界用ノイズ抑制シート。 In the alloy powder, 3 atomic% or less of the Fe is substituted with one or more elements selected from Al, Co, Ni, Cr, Nb, Mo, Ta, and W. The noise suppression sheet | seat for near fields as described in any one of 5.
  7. 　前記合金粉末のアスペクト比の平均値が１０以上１００以下である、請求項１～６のいずれか一項に記載の近傍界用ノイズ抑制シート。 The noise suppressing sheet for near field according to any one of claims 1 to 6, wherein an average value of aspect ratios of the alloy powder is 10 or more and 100 or less.
  8. 　前記合金粉末の厚さの平均値が０．１μｍ以上１．５μｍ以下である、請求項１～７のいずれか一項に記載の近傍界用ノイズ抑制シート。 The near-field noise suppression sheet according to any one of claims 1 to 7, wherein the average value of the thickness of the alloy powder is 0.1 μm or more and 1.5 μm or less.
  9. 　前記近傍界用ノイズ抑制シートの表面抵抗が１０５Ω/□以上である、請求項１～８のいずれか一項に記載の近傍界用ノイズ抑制シート。 The near-field noise suppression sheet according to any one of claims 1 to 8, wherein a surface resistance of the near-field noise suppression sheet is 10 5 Ω / □ or more.
  10. 　前記基材はハロゲン元素を含まない、請求項１～９のいずれか一項に記載の近傍界用ノイズ抑制シート。 The near-field noise suppression sheet according to any one of claims 1 to 9, wherein the base material does not contain a halogen element.
  11. 　前記ノイズ抑制シートは、シリコン系、チタン系、アルミニウム系およびジルコニウム系のうちから選択される１種以上の酸化物を含み、前記酸化物の粒径が１００ｎｍ以下である、請求項１～１０のいずれか一項に記載の近傍界用ノイズ抑制シート。 The noise suppression sheet according to any one of claims 1 to 10, wherein the noise suppression sheet contains one or more oxides selected from among silicon based, titanium based, aluminum based and zirconium based, and the particle size of the oxide is 100 nm or less. The near-field noise suppression sheet according to any one of the preceding claims.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11354973A (en) * 1998-06-04 1999-12-24 Hitachi Metals Ltd Electromagnetic wave absorber
WO2002000954A1 (en) * 2000-06-29 2002-01-03 Sumitomo Special Metals Co., Ltd Soft magnetic alloy powder for electromagnetic wave absorbing sheet, electromagnetic wave absorbing sheet, and method for manufacturing them
JP2003045708A (en) * 2001-05-23 2003-02-14 Alps Electric Co Ltd Wave absorber and manufacturing method therefor
JP2004111956A (en) * 2002-08-30 2004-04-08 Nec Tokin Corp Magnetic loss material and its manufacturing method
JP2004288941A (en) * 2003-03-24 2004-10-14 Hitachi Metals Ltd Noise suppression sheet
JP2007281074A (en) * 2006-04-04 2007-10-25 Hitachi Metals Ltd Noise suppression sheet
JP2010135567A (en) * 2008-12-04 2010-06-17 Tohoku Univ Radio wave absorbing material

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3990658B2 (en) * 2002-08-19 2007-10-17 住友電気工業株式会社 Electromagnetic wave absorber
JP2009021403A (en) * 2007-07-12 2009-01-29 Alps Electric Co Ltd Electromagnetic wave suppressing sheet
JP4818339B2 (en) * 2007-10-29 2011-11-16 ソニーケミカル＆インフォメーションデバイス株式会社 Magnetic sheet
JP2012186384A (en) 2011-03-07 2012-09-27 Tdk Corp Electromagnetic noise suppression member
JP5708454B2 (en) * 2011-11-17 2015-04-30 日立化成株式会社 Alcohol solution and sintered magnet
JP2013182931A (en) 2012-02-29 2013-09-12 Tdk Corp Electromagnetic noise suppression member
JP6388761B2 (en) 2013-08-29 2018-09-12 株式会社トーキン Electromagnetic interference suppression sheet and manufacturing method thereof
JP5700869B2 (en) * 2013-09-13 2015-04-15 株式会社リケン Near-field electromagnetic wave absorbing sheet
JP6554278B2 (en) 2014-11-14 2019-07-31 株式会社リケン Soft magnetic alloys and magnetic parts
JP6558887B2 (en) 2014-11-14 2019-08-14 株式会社リケン Soft magnetic alloys and magnetic parts
JP6441756B2 (en) * 2015-07-10 2018-12-19 株式会社トーキン Flame retardant composite magnetic material

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11354973A (en) * 1998-06-04 1999-12-24 Hitachi Metals Ltd Electromagnetic wave absorber
WO2002000954A1 (en) * 2000-06-29 2002-01-03 Sumitomo Special Metals Co., Ltd Soft magnetic alloy powder for electromagnetic wave absorbing sheet, electromagnetic wave absorbing sheet, and method for manufacturing them
JP2003045708A (en) * 2001-05-23 2003-02-14 Alps Electric Co Ltd Wave absorber and manufacturing method therefor
JP2004111956A (en) * 2002-08-30 2004-04-08 Nec Tokin Corp Magnetic loss material and its manufacturing method
JP2004288941A (en) * 2003-03-24 2004-10-14 Hitachi Metals Ltd Noise suppression sheet
JP2007281074A (en) * 2006-04-04 2007-10-25 Hitachi Metals Ltd Noise suppression sheet
JP2010135567A (en) * 2008-12-04 2010-06-17 Tohoku Univ Radio wave absorbing material

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