JP5360947B2 - Resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material effectively absorbing unnecessary electromagnetic waves within a high-frequency region. <P>SOLUTION: The resin composition contains 50-98 pts.wt. hexagonal ferrite to 100 pts.wt. total resin composition. As the hexagonal ferrite, one or more selected from the group consisting of (M-type) BaM<SB>x</SB>Fe<SB>(12-x)</SB>O<SB>19</SB>, (Z-type) Ba<SB>3</SB>M<SB>&beta;</SB>Fe<SB>24</SB>O<SB>41</SB>or (Y-type) Ba<SB>2</SB>M<SB>2</SB>Fe<SB>12</SB>O<SB>22</SB>(wherein M is one or a combination of two or more chosen from the group consisting of Ti, Co, Ni, Zn, Mn and Cu, provided that Ba may be partially or completely replaced with Sr) are preferably used. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

The present invention relates to an electromagnetic wave absorbing material composed of magnetic powder and resin.
The present invention relates to an electromagnetic wave absorbing material excellent in electromagnetic wave absorption characteristics particularly in a high frequency region.

  In general, an electronic member such as a wiring part of an electronic circuit or a CPU generates an electromagnetic wave. However, the electromagnetic wave may affect other electronic members and cause malfunction. Moreover, when transmitting / receiving electromagnetic waves by information communication, it may be obstructed by unnecessary electromagnetic waves other than the target electromagnetic waves, and may interfere with the transmission / reception of electromagnetic waves.

  A method of using a composite material in which a magnetic material such as metal fine particles or ferrite is blended in a resin has been known as a means for absorbing such unnecessary electromagnetic waves to prevent malfunction of electronic devices and information communication failure ( For example, see Patent Document 1). However, in recent years, with the increase in information communication speed and capacity, the AC frequency of electronic circuits such as personal computers, mobile phones, and DVDs and the electromagnetic wave frequency used for information communication are increasing. In some cases, it has been difficult to effectively absorb electromagnetic waves with magnetic metals.

  In addition, new information communication technologies using high frequency electromagnetic waves are being developed. Here, the high frequency region indicates a region exceeding 1 GHz. For example, in the image technology field, a method has been developed in which image information is transmitted through space using high-frequency electromagnetic waves without going through a cable, and is transmitted to an image device for display. In communication equipment for automobiles, a system has been developed that detects other automobiles and obstacles in front of the automobile with electromagnetic waves in the millimeter wave region and prevents a collision in advance.

As described above, cases of using electromagnetic waves in a high frequency range that have not been used so much in the past are increasing. However, electronic devices that transmit and receive these electromagnetic waves and their peripheral devices are prevented from malfunctioning and reflected waves. A material that can easily and effectively prevent communication failure has not been obtained.
Japanese Patent Laid-Open No. 2005-19846

  An object of this invention is to provide the material which absorbs the unnecessary electromagnetic wave of a high frequency area | region effectively.

As a result of intensive studies on the composition of magnetic powder and resin in order to solve the above problems, the present inventors have found that a composition in which hexagonal ferrite is mixed with a resin exhibits an excellent radio wave absorption effect at a high frequency of 1 GHz or higher. And found the present invention.
That is, this invention is a coating composition containing the resin composition, the sheet | seat which consists of this resin composition, and this resin composition as described below.

(1) In a resin composition containing hexagonal ferrite and a resin,
The hexagonal ferrite is Y-type ferrite or Z-type ferrite;
The Y-type ferrite metal is Zn,
The metal of the Z-type ferrite is Co or a combination of Co and Zn;
The resin is a fluororesin having a fluorine atom in the polymer molecular chain;
A resin composition comprising 50 to 98 parts by weight of hexagonal ferrite with respect to 100 parts by weight of the total amount of the resin composition.
(2) The resin composition as set forth in (1), comprising 90 to 95 parts by weight of the hexagonal ferrite.
( 3 ) The fluororesin is tetrafluoroethylene, perfluoroalkoxyalkane, perfluoroethylene-propene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-chlorofluoro. (1) or (2) characterized in that it is at least one selected from an ethylene copolymer, a tetrafluoroethylene-perfluoroidioxole copolymer, a polyvinylidene fluoride, and a tetrafluoroethylene-propylene copolymer. ) .
( 4 ) The resin composition as described in ( 3 ), wherein the fluororesin is a tetrafluoroethylene-propylene copolymer.
( 5 ) The resin composition according to ( 4 ), wherein the proportion of the number of propylene units in the total number of monomer units in the tetrafluoroethylene-propylene copolymer is 30 to 50%.
( 6 ) The resin composition according to ( 4 ) or ( 5 ), wherein the tetrafluoroethylene-propylene copolymer has a Mooney viscosity of 20 to 50 ML (1 + 10) 100 ° C.
( 7 ) The resin composition according to (1) , wherein the hexagonal ferrite is one or a mixture of two or more selected from the group consisting of M type, Z type, and Y type of the following general formula object.
(M-type) BaM _X Fe _(12-X) O ₁₉
(Z-type) Ba ₃ M _β Fe ₂₄ O ₄₁
(Y type) Ba ₂ M ₂ Fe ₁₂ O ₂₂
In the formula, M is Co or a combination of Co and Zn in the Z type, Zn in the Y type, and part or all of Ba may be replaced with Sr.
In the formula of M type, X is an integer of 0 to 12, and in the formula of Z type, β is 0.1 to 20.
( 8 ) When the hexagonal ferrite includes Z-type, when the molar ratio of the Z-type Fe component and M component is expressed as Fe component: M component = 24: β, the condition of 0.5 ≦ β ≦ 2.6 The resin composition as described in ( 7 ) characterized by satisfy | filling.
( 9 ) When the hexagonal ferrite includes Z-type, the Z-type is Ba ₃ Co _D Zn _E Fe ₂₄ O ₄₁ and 0.4 ≦ D ≦ 2.0, and 0.1 ≦ E ≦ 1.0. The resin composition as described in ( 7 ) or ( 8 ) characterized by satisfying the following condition.
( 10 ) When the hexagonal ferrite includes Y type, the Y type is Ba ₂ (Zn _F ) ₂ Fe ₁₂ O ₂₂ and satisfies the condition of 0.35 ≦ F ≦ 1.35 ( The resin composition as described in 7 ).
( 11 ) The resin is 2 to 47 parts by weight, the hexagonal ferrite is 50 to 95 parts by weight, and the soft magnetic ferrite, soft magnetic alloy, and thermal conductivity is 20 W / 100 parts by weight based on 100 parts by weight of the total resin composition. (1) to ( 12 ) comprising 3 to 48 parts by weight of a mixture composed of one or a combination of two or more selected from the group consisting of a highly heat-conductive inorganic substance of m · K or more and a conductive substance. ).
( 12 ) A sheet comprising the resin composition according to any one of (1) to ( 11 ).
( 13 ) An adhesive sheet having an adhesive layer on the sheet surface according to ( 12 ).
( 14 ) A paint containing the resin composition according to any one of (1) to ( 11 ).
( 15 ) An electromagnetic wave absorbing sheet having a layer containing the paint according to ( 14 ) on a resin sheet surface.
( 16 ) The sheet according to any one of ( 12 ), ( 13 ), and ( 15 ), which is used to absorb electromagnetic waves generated from circuits of electrical products and electronic devices.

  The resin composition of the present invention can effectively absorb unnecessary electromagnetic waves in a high frequency region.

The present invention will be described in detail below.
The present invention is a composition comprising hexagonal ferrite and a resin.
Hexagonal ferrite is a ferrite in which the crystal lattice has a hexagonal columnar shape, and exhibits a high resonance frequency because it has magnetic anisotropy in the c-plane and c-axis directions.

The hexagonal ferrite is the difference in composition and structure, _{(M-type) BaM X Fe (12-X} ) O 19, (Z _{-type) Ba 3 M β Fe 24 O} 41, (Y _-type) Ba ₂ M _{2 Fe 12} O ₂₂ (W type) BaM ₂ Fe ₁₆ O ₂₇ , (X type) Ba ₂ M ₂ Fe ₂₈ O ₄₆ , (U type) Ba ₄ M ₂ Fe ₃₆ O ₆₀ . In the formula, M is one or a combination of two or more selected from the group consisting of Ti, Co, Ni, Zn, Mn, and Cu, and part or all of Ba may be replaced with Sr. In the (M type) formula, X is an integer of 0 to 12, and β is 0.1 to 20.
Among the hexagonal ferrites, the hexagonal ferrite used in the present invention is preferably M-type, Y-type, or Z-type from the viewpoint of electromagnetic wave absorption.

The M-type ferrite is also called a magnetoplumbite type ferrite and is represented by the general formula BaM _X Fe _(12-X) O ₁₉ . In the formula, the M component is one or a combination of two or more selected from the atomic group consisting of Ti, Co, Ni, Zn, Mn, and Cu. Part or all of Ba may be replaced with Sr.
Increasing the number of moles of the M component relative to the number of moles of Fe atoms in the M-type ferrite decreases the resonance frequency. The preferred number of moles of the M component relative to the number of moles of Fe atoms in the present invention is in the range of 1 ≦ α ≦ 6.4 when expressed as Fe component: M component = 10: α. When α is 1 or more, the amount of electromagnetic wave absorption is high, and when it is 6.4 or less, the resonance frequency at which the electromagnetic wave absorption effect is maximized is high.

In the above formula of M-type ferrite, the case where the metal element M contains at least Co is preferable from the viewpoint of electromagnetic wave absorption, more preferably a combination of Ti and Co, and particularly preferably a combination of Ti, Co and Zn.
The structure of M-type ferrite _{Ba (Ti A Co B Zn C} ) is preferred composition range of each component when expressed in _{2 Fe 10 O 19 0.3 ≦ A} ≦ 1.5,0.1 ≦ B ≦ 1. 0, and 0.1 ≦ C ≦ 0.7. Above the lower limit of each composition range is preferable because a sufficient amount of electromagnetic wave absorption is obtained, and below the upper limit is preferable because the resonance frequency is high.

Y-type ferrite is classified as a Ferrox planar type and is represented by the general formula Ba ₂ M ₂ Fe ₁₂ O ₂₂ . Part or all of Ba may be replaced by Sr, and M is preferably one or a combination of two or more selected from an atomic group consisting of Ti, Co, Ni, Zn, Mn, and Cu. Among these, Zn is particularly preferable because it has a high resonance frequency and a large amount of electromagnetic wave absorption.
When the structural formula when M is Zn is expressed as Ba ₂ (Zn _F ) ₂ Fe ₁₂ O ₂₂ , the composition of Zn preferably satisfies the condition of 0.35 ≦ F ≦ 1.35. When F is 0.35 or more, a sufficient amount of electromagnetic wave absorption is obtained, and when F is 1.35 or less, the resonance frequency is high, which is preferable.

Z-type ferrite is also classified as a Ferrox planar type and is represented by the general formula Ba ₃ M _β Fe ₂₄ O ₄₁ . Part or all of Ba may be replaced by Sr, and M is preferably one or a combination of two or more selected from an atomic group consisting of Ti, Co, Ni, Zn, Mn, and Cu. Among them, the case where at least Co is included is preferable, and the case where Co and Zn are further included is particularly preferable because the resonance frequency is high and the electromagnetic wave absorption amount is also large.
When the molar ratio of the Fe component and the M component of the Z-type ferrite is expressed by Fe component: M component = 24: β, it is preferable that the condition of 0.5 ≦ β ≦ 2.6 is satisfied. If β is 0.5 or more, a sufficient amount of electromagnetic wave absorption is obtained, and 2.6 or less is preferable because the frequency of electromagnetic waves that can be absorbed is high.
M is a structural formula in the case of _{Co Ba 3 Co D Zn E Fe} 24 preferred composition range of each component when expressed as _{O 41} is 0.4 ≦ D ≦ 2.0, and 0.1 ≦ E ≦ 1. 0. Above the lower limit of each composition range is preferable because a sufficient amount of electromagnetic wave absorption is obtained, and below the upper limit is preferable because the resonance frequency is high.

The hexagonal ferrite is preferably a powder. The particle size of the powder is preferably 1 to 50 μm, and more preferably in the range of 1 to 10 μm. If it is 1 μm or more, the handleability is good, and if it is 50 μm or less, the dispersibility in the resin is excellent.
When the hexagonal ferrite powder is used by mixing a large particle size and a small particle size, the space between the particles when mixed with the resin can be reduced, so the filling rate for the resin can be increased, The electromagnetic wave absorption amount of the composition can be improved.
The specific surface area of the hexagonal ferrite powder particles is preferably 0.3 to ² m ² / g. If it is 0.3 m ² / g or more, it is excellent in flexibility when mixed with a resin and formed into a sheet, and if it is 2 m ² / g or less, it can be blended at a high concentration with respect to the resin, so that the electromagnetic wave absorption of the sheet can be increased.

The structure of hexagonal ferrite is specified by X-ray fluorescence analysis (XRF). Specifically, it is obtained by quantitative analysis by a Fundamental Parameter method using a wavelength dispersive X-ray fluorescence analyzer.
The form of the hexagonal ferrite powder particles includes spherical, plate-like, etc., but in the case of plate-like, the hexagonal ferrite is easily oriented horizontally with respect to the sheet plane at the stage of mixing with the resin and forming into a sheet, Orienting horizontally is preferable because there is an advantage that the electromagnetic wave absorption amount of the resin composition sheet can be improved and the sheet thickness can be reduced.
When the hexagonal ferrite powder particles are plate-like, the thickness of the plate is preferably 0.05 μm to 5 μm, and more preferably 0.1 μm to 1 μm. If it is 0.05 μm or more, there is an advantage that the shape can be maintained at the time of kneading with the resin, and if it is 5 μm or less, the sheet of the resin composition can be thinned.

The hexagonal ferrite can be subjected to a coupling treatment on the particle surface for the purpose of improving the adhesion to the resin.
Examples of coupling agents include isopropyl triisostearoyl titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraisopropyl titanate, Tetrabutyl titanate, tetraoctyl bis (ditridecyl phosphite) titanate, isopropyl trioctanoyl titanate, isopropyl tridodecyl benzene sulfonyl titanate, isopropyl tri (dioctyl phosphate) titanate, bis (dioctyl pyrophosphate) ethylene titanate, isopropyl dimethacrylisostearoyl Titanate, tetra (2,2-diallyloxymethyl-1- Titanium coupling agents such as til) bis (ditridecyl phosphite) titanate, isopropyl tricumyl phenyl titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, isopropyl isostearoyl diacryl titanate, γ-aminopropyltriethoxysilane, N -Β- (aminoethyl) -γ-aminopropyltrimethoxysilane, γ-glycidoxy-propyltrimethoxysilane, β- (3,4-epoxy-cyclohexyl) ethyltrimethoxysilane, vinyltriethoxysilane, vinyl-tris ( 2-methoxyethoxy) silane, γ-mercaptopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysila N- (3-triethoxysilylpropyl) urea, methyltrimethoxysilane, octadecyltriethoxylalane, vinyltonoacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ-anilinopropyltrimethoxysilane, Coupling agents containing silicone such as octadecyldimethyl [3- (trimethoxysilyl) promepyl] ammonium chloride, γ-chloropropylmethyldimethoxysilane, methyltrichlorosilane, polyalkylene oxide silanes, perfluoroalkyltrimethoxysilanes, Examples include one or a combination of two or more coupling agents such as aluminum-based, zirconium-based, chromium-based, iron-based, tin-based, such as acetoalkoxyaluminum diisopropylate. The

In order to improve the adhesion between the hexagonal ferrite and the fluororesin, it is preferable to use a coupling agent or a surface treatment agent having F atoms in the molecule.
The pH of the hexagonal ferrite is preferably 7-9, more preferably 7-8.5. When the pH is in the range of 7 to 9, the adhesion to the resin is good, and the flexibility of the sheet of the resin composition is excellent even when the composition of the hexagonal ferrite is increased.
Ferrite plated particles obtained by plating hexagonal ferrite on the surface of the metal powder can be blended with the resin.

  The composition of the hexagonal ferrite resin composition is required to be 50 to 98 parts by weight, preferably 75 to 95 parts by weight, more preferably 90 to 95 parts by weight with respect to 100 parts by weight of the total amount of the resin composition. Part. When the amount is 50 parts by weight or more, effective electromagnetic wave absorption performance is obtained, and when the amount is 98 parts by weight or less, the composite property with the resin is excellent.

The resin mixed with hexagonal ferrite may be either a thermoplastic resin or a thermosetting resin. As the thermoplastic resin, a polymer or copolymer of a monomer having an unsaturated group such as a double bond or a triple bond can be used.
Polymer and copolymer monomers include ethylene, propylene, butadiene, isoprene, styrene, α-methylstyrene, methacrylic acid, acrylic acid, methacrylic acid ester, acrylic acid ester, vinyl chloride, vinylidene chloride, fluorinated ethylene, acrylonitrile , Maleic anhydride, and vinyl acetate. Among them, fluorinated ethylene is preferable. Fluorinated ethylene can be represented by the following general formula (B).

（Ｒ１〜Ｒ４は、Ｈ、Ｆ、Ｃｌ、炭化水素基、アルコキシ基、Ｈ原子の一部又は全てがＦ原子で置換された炭化水素基又はアルコキシ基の中から任意に選択される。）

(R1 to R4 are arbitrarily selected from H, F, Cl, a hydrocarbon group, an alkoxy group, a hydrocarbon group or an alkoxy group in which some or all of the H atoms are substituted with F atoms.)

  Other thermoplastic resins include polyphenylene ether, polyamide, polyimide, polyamideimide, polycarbonate, polyester, polyacetal, polyphenylene sulfide, polyethylene glycol, polyetherimide, polyketone, polyetheretherketone, polyethersulfone, polyarylate, etc. As an example.

Examples of the thermosetting resin include phenol resin, epoxy resin, cyanate ester, polyimide, polyurethane, bismaleimide resin, alkyd resin, unsaturated polyester, silicone resin, benzocyclobutene, and the like. The thermoplastic resin and thermosetting resin may be modified with a compound having a functional group.
The functional group may include one or two or more selected from vinyl group, allyl group, carboxyl group, acid anhydride group, ester group, hydroxyl group, amino group, amide group, imide group, epoxy group, and halogen.

Those having the F atom, Cl atom, and Br atom in the molecular chain are excellent in flame retardancy and can be preferably used as the above-mentioned thermal plastic resin and thermosetting resin. It is particularly preferable because of its excellent properties, chemical resistance, low water absorption, and dielectric properties.
In the resin having fluorine atoms, the weight ratio of fluorine atoms in the molecular structure of the polymer is preferably 10 to 70% by weight based on the total amount of the polymer. If it is 10% by weight or more, it is excellent in flame retardancy, chemical resistance, low water absorption, and dielectric properties, and if it is 70% by weight or less, kneading with hexagonal ferrite is easy. Among resins having a fluorine atom, a group called a fluororesin having a structure represented by the following general formula (A) in the molecular chain is preferable.

（Ｒ１〜Ｒ４は、Ｈ、Ｆ、Ｃｌ、炭化水素基、アルコキシ基、Ｈ原子の一部又は全てがＦ原子で置換された炭化水素基又はアルコキシ基の中から任意に選択されるが、少なくとも１個のＦ原子を有する。ｎは５以上の整数。）

(R1 to R4 are arbitrarily selected from H, F, Cl, a hydrocarbon group, an alkoxy group, a hydrocarbon group or an alkoxy group in which some or all of the H atoms are substituted with F atoms, but at least (It has one F atom. N is an integer of 5 or more.)

  Examples of fluororesin include tetrafluoroethylene, perfluoroalkoxyalkane, perfluoroethylene-propene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-chlorofluoroethylene. Copolymer, tetrafluoroethylene-perfluoroidioxole copolymer, polyvinylidene fluoride, propylene-tetrafluoroethylene copolymer, etc., among which tetrafluoroethylene-propylene copolymer and tetrafluoroethylene-ethylene are mentioned. A copolymer is preferably used, and a tetrafluoroethylene-propylene copolymer is most preferable.

The tetrafluoroethylene-propylene copolymer is a copolymer of a tetrafluoroethylene monomer and a propylene monomer, and various properties of the resin vary depending on the composition ratio of the two monomers.
A preferred ratio of the number of propylene units to the total number of monomer units of the tetrafluoroethylene-propylene copolymer is 30 to 50%. If it is 30% or more, hexagonal ferrite can be blended at a high concentration with respect to the resin component, and if it is 50% or less, the flame retardancy, chemical resistance, low water absorption and dielectric properties of the composition are excellent.

The Mooney viscosity of the tetrafluoroethylene-propylene copolymer is preferably 20 to 50 ML (1 + 10) 100 ° C. At 20 ML (1 + 10) 100 ° C. or higher, the sheet strength of the composition with hexagonal ferrite is excellent, and at 50 ML (1 + 10) 100 ° C. or lower, even if hexagonal ferrite is blended in a high composition, the composition sheet is sufficient. Has flexibility.
Here, the Mooney viscosity is measured in accordance with JIS K6300. For example, in the case of 50 ML (1 + 10) 100 ° C., 50 M is the Mooney viscosity, L is the rotor shape and the L shape is (1 + 10). Represents a preheating time (minute) of 1 minute and a rotor rotation time (minute) of 10 minutes, and 100 ° C. represents a test temperature of 100 ° C.

In addition to the resin and hexagonal ferrite, the composition of the present invention includes one or a combination of two or more selected from the group consisting of soft magnetic ferrite, soft magnetic alloy, highly heat conductive inorganic material, and conductive material as a third component. Can be added.
The preferred composition of the above components is 2 to 47 parts by weight of resin, 50 to 95 parts by weight of hexagonal ferrite, and 3 to 48 parts by weight of the third component with respect to 100 parts by weight of the total resin composition. When the third component is 3 parts by weight or more, the characteristics of the third component are expressed, and when it is 48 parts by weight or less, the electromagnetic wave absorption characteristics in the high frequency region of the hexagonal ferrite are maintained.

Specific examples of the soft magnetic ferrite include MnFe ₂ O ₄ , CoFe ₂ O ₄ , NiFe ₂ O ₄ , CuFe ₂ O ₄ , ZnFe ₂ O ₄ , MgFe ₂ O ₄ , Fe ₃ O ₄ , Cu—Zn ferrite, Ni-Zn ferrite, Mn-Zn-ferrite, etc. are mentioned.
Specific examples of the soft magnetic alloy include Fe-Ni, Fe-Co, Fe-Cr, Fe-Si, Fe-Al, Fe-Cr-Si, Fe-Cr-Al, Fe-Al-Si, Fe- Pt etc. are mentioned. By adding a magnetic material different from the hexagonal ferrite to the resin composition, the frequency range of electromagnetic waves absorbed by the composition can be expanded.

As the inorganic material having high thermal conductivity, those having a thermal conductivity of 20 W / m · K or more are particularly preferable. Specific examples thereof include silica, beryllia, titanium oxide, zirconia, bengara, zinc oxide, aluminum oxide, and hydroxide. Examples thereof include metal nitrides such as aluminum, magnesium hydroxide, graphite, boron nitride, aluminum nitride, and iron nitride, and metals such as copper and aluminum. By adding the inorganic material having high thermal conductivity, a composition having both electromagnetic wave absorption and thermal conductivity functions can be obtained.
The conductive material is preferably a metal such as iron, copper, or aluminum, but a semiconductor such as Si, Ge, ZnO, or SiC can be used.

For the purpose of imparting flame retardancy, flame retardants such as organic halides, metal hydroxides, and phosphorus compounds may be added to the composition of the present invention.
Specific examples thereof include hexabromobenzene, decabromobenzyl phenyl ether, decabromobenzyl phenyl oxide, tetrabromobisphenol, tetrabromophthalic anhydride, tetrabromobisphenol A, tricresyl phosphate, triphenyl phosphate, triallyl phosphate, trichloro Examples include ethyl phosphate, halogen-containing condensed phosphate ester, phosphazene, chlorinated paraffin, perchloropentacyclodecane, aluminum hydroxide, magnesium hydroxide, antimony trioxide, antimony pentoxide, zinc borate, ammonium bromide, titanium phosphate, etc. be able to.

In the production of the composition of the present invention, a kneader such as a pressure kneader, a Banbury mixer, a twin screw extruder, a single screw extruder, or a roll mixer can be used.
When the composition is subjected to a molding process such as film molding or sheet molding, methods such as injection molding, transfer molding, press molding, T-die extrusion molding, calendar molding, and roll rolling can be used. These molding processes can be performed in the presence of a magnetic field or an electric field, or while irradiating ultrasonic waves, electromagnetic waves, or ultraviolet rays, as necessary.

The composition of the present invention can also crosslink resin components for the purpose of improving mechanical properties and solvent resistance.
After mixing the composition of this invention with a solvent and disperse | distributing uniformly, it can also be set as a coating film form by apply | coating and drying to a support body.
After impregnating a varnish obtained by mixing the composition of the present invention with a solvent and uniformly dispersing it into a fibrous sheet such as cloth, paper, glass cloth, and the like, by volatilizing the solvent, these fibrous sheets and A composite of the composition can be obtained.

The composition of the present invention can also be used as a paint. In that case, the composition and a solvent such as toluene, xylene, methyl ethyl ketone, acetone, methanol, propanol, cyclohexane, hexane, etc. are mixed to form a solution, emulsion, suspension, slurry, paste, or a curable liquid silicone resin. It is preferable to use it dispersed in an epoxy resin or the like.
An electromagnetic wave absorbing function can be imparted by the presence of the paint of the above composition. Specific examples include a case where it is applied to a resin film, a sheet molded body, and the like, and a case where it is applied to a metal structure to prevent electromagnetic wave reflection.

The composition of the present invention can effectively absorb electromagnetic waves in a high frequency region. The high frequency region in the present invention refers to a region of 1 GHz or more, and particularly shows a remarkable effect at 5 GHz or more.
By sticking a sheet made of the composition of the present invention to an object, an electromagnetic wave absorbing function can be imparted to the object. If the thickness is 0.05 mm or more, the thickness of the sheet can be easily controlled and the amount of electromagnetic wave absorption is sufficient.

  It is preferable that the sheet | seat which consists of a composition of this invention has an adhesion layer. When the sheet has an adhesive layer, it is useful when pasting at a desired location. Examples of a method for applying an adhesive layer to the sheet include a method of attaching a double-sided tape to the sheet surface, a method of applying an adhesive material to the sheet surface, and the like.

A sheet made of the composition of the present invention is attached to a member such as a wiring board or a CPU, LSI, or wiring mounted in an electronic device or information communication device such as a mobile phone, a personal computer, or a digital camera. Used to absorb unnecessary electromagnetic noise that causes malfunction.
A sheet made of the composition of the present invention is used to prevent reflection of radio waves transmitted from a vehicle-mounted device by being affixed to a structure of an automatic toll collection system installed on a road or painted as a paint. Used for.

The seat made of the composition of the present invention communicates road traffic information such as traffic jams and position information, front obstacle information to a running car, in-vehicle equipment used in a road traffic information system and its peripheral members, Used to prevent communication failures.
The sheet made of the composition of the present invention is used for preventing reflection of radar waves in structures such as buildings, bridges, and steel towers.
The sheet | seat which consists of a composition of this invention is used for the ceiling and wall of a building room for the purpose of the leakage prevention of indoor wireless communication.

The composition sheet was evaluated by the methods shown in the following (1) to (5).
(1) Radio wave absorption characteristics <Evaluation method 1>
The measurement was carried out according to the transmission attenuation power ratio method. On the micro split line (MSL) having a line width of 2.2 mm and a characteristic impedance of 50Ω, the entire substrate is covered with a sheet having a width of 100 mm and a length of 50 mm or more, which is the size of the MSL substrate. The parameter value is obtained, and the electromagnetic wave attenuation (R) by the sheet is obtained by the following equation.
(R) = 10 log [10 ^{S21 / 10} / (1-10 ^{S11 / 10} )] [dB]
This (R) value is shown in the table.
<Evaluation method 2>
A doughnut-shaped test piece having an outer diameter of 7 mm and an inner diameter of 3 mm is punched from the sheet, and this test piece is inserted into the coaxial rod without any gap. The S11 (sample) parameter was measured using a network analyzer with the ends of the coaxial rods short-circuited. Further, S11 (base) in an empty state where no sample was inserted was measured, and the electromagnetic wave absorption amount was calculated from the following equation.
[Electromagnetic wave absorption] = [S11 (sample)]-[S11 (base)] (dB)
The value of the frequency at which the electromagnetic wave absorption amount becomes the maximum value and the absorption amount at that time are shown in the table.

(2) Flexibility test A 10 cm square composition sheet is folded by hand as shown in FIG. 1, and the state of the sheet is observed after leaving it for 10 seconds. If it is restored to the original state before folding without a crease or the like, it is acceptable (O), and if it is not restored to the original state, it is unacceptable (X).

(3) Solvent resistance test A 1 cm square composition sheet is immersed in toluene or chloroform at room temperature for 24 hours. When the magnetic powder separated from the composition in the solvent, it was marked as x.

(4) Hot water resistance test (PCT test)
A 1 cm square composition sheet is placed under 1.2 atmosphere of saturated steam for 2 hours, and then the sheet is folded. As a result, when the sheet is restored to the original sheet state, it is acceptable (O), and when the sheet is broken or broken, it is unacceptable (X).

(5) Combustion test A part of the composition sheet was cut out, brought into direct contact with the flame of the gas burner for 10 seconds, separated from the flame, and burned for 5 seconds or more. ).

(6) Thermal conductivity test A rapid thermal conductivity meter KEMTHRM QTM-D3 type (manufactured by Kyoto Electronics Industry) was used. A sheet sample to be measured is placed on a standard sample having a known thermal conductivity, and the overall thermal conductivity (Q1) of the standard sample and the sheet is measured. When the thermal conductivity of the reference sample is (Q2), the deviation (ε) is obtained from the following equation.
(Ε) = [(Q1) − (Q2)] / (Q2)
(Ε) was plotted against log (Q2), the thermal conductivity when (ε) was zero was determined by interpolation, and the thermal conductivity of the sheet sample was determined.
Reference samples include silicon rubber (Q2) = 0.241 (W / m · K), rubber plate (Q2) = 0.536 (W / m · K), quartz glass (Q2) = 1.416 ( W / m · K) and zirconia (Q2) = 3.277 (W / m · K) were used.
The resins used in the examples are shown in Tables 1 and 2, and the hexagonal ferrites are shown in Tables 3, 4 and 5.

Examples are shown below. In addition, Examples 1-14, 25-27, 30-41 are missing numbers.
[ Reference Example 1 ]
15 g (A-1) of tetrafluoroethylene-propylene copolymer was put into a kneader and kneaded in a nitrogen atmosphere at 130 ° C. for 3 minutes, and then M-type hexagonal ferrite, Ba (Ti _0.55 Co _{1. 33} Zn _0.33 ) ₂ Fe ₁₀ O ₁₉ (M-1) 135 g was added over 5 minutes while kneading with the resin. During this time, the sample temperature continued to rise and eventually reached 170 ° C. Kneading was continued for 10 minutes even after the total amount of (M-1) was added, and compositions (A-1) and (M-1) were obtained. The composition of each component with respect to 100 parts by weight of the total composition is (A-1) 10 parts by weight (M-1) 90 parts by weight. Next, using a compression molding machine, the composition was compression molded at 200 ° C. and 10 MPa for 5 minutes to obtain a flexible sheet having a thickness of 2 mm. Table 6 shows the evaluation results of the sheet.

[ Reference Example 2 ]
The same procedure as in Example 1 was performed except that (A-1) 22.5 g and (M-1) 127.5 g were used as the raw material composition of the composition. The composition of each component with respect to 100 parts by weight of the total composition is (A-1) 15 parts by weight, and (M-1) is 85 parts by weight. Table 6 shows the evaluation results of the sheet.
[ Reference Example 3 ]
The same procedure as in Example 1 was performed except that (A-1) 4 g and (M-1) 96 g were used as the raw material composition of the composition. The composition of each component with respect to 100 parts by weight of the total composition is (A-1) 4 parts by weight, and (M-1) is 96 parts by weight. Table 6 shows the evaluation results of the sheet.
[ Reference Example 4 ]
The composition was obtained in the same manner as in Example 1 except that (A-1) 30 g and (M-1) 120 g were used as the raw material composition of the composition. The composition of each component with respect to 100 parts by weight of the total composition is (A-1) 20 parts by weight, and (M-1) is 80 parts by weight. Table 6 shows the evaluation results of the sheet.
[ Reference Example 5 ]
The same procedure as in Example 1 was performed except that the raw material composition of the composition was (A-1) 60 g and (M-1) 90 g. The composition of each component with respect to 100 parts by weight of the total composition is (A-1) 40 parts by weight, and (M-1) is 60 parts by weight. Table 6 shows the evaluation results of the sheet.

[ Reference Example 6 ]
The same procedure as in Example 1 was performed except that Ba (Ti _1.5 Co _1.0 Zn _0.4 ) ₂ Fe ₁₀ O ₁₉ M-type hexagonal ferrite (M-2) was used instead of (M-1). went. Table 6 shows the evaluation results of the sheet.
[ Reference Example 7 ]
The same procedure as in Example 1 was performed except that M-type hexagonal ferrite (M-3) of Ba (Ti _0.40 Co _0.2 Zn _0.1 ) ₂ Fe ₁₀ O ₁₉ was used instead of (M-1). went. Table 6 shows the evaluation results of the sheet.
[ Reference Example 8 ]
The same procedure as in Example 1 was performed except that M-type hexagonal ferrite (M-4) of Ba (Ti _0.20 Co _0.09 Zn _0.11 ) ₂ Fe ₁₀ O ₁₉ was used instead of (M-1). went. Table 6 shows the evaluation results of the sheet.

[ Reference Example 9 ]
The same procedure as in Example 1 was performed except that Ba (Ti _1.7 CoZn _0.8 ) ₂ Fe ₁₀ O ₁₉ M-type hexagonal ferrite (M-5) was used instead of (M-1). Table 7 shows the evaluation results of the sheet.
[ Reference Example 10 ]
The same procedure as in Example 1 was conducted except that Ba (Ti _0.6 Co _0.6 ) ₂ Fe ₁₀ O ₁₉ M-type hexagonal ferrite (M-6) was used instead of (M-1). Table 7 shows the evaluation results of the sheet.
[ Reference Example 11 ]
The same procedure as in Example 1 was conducted except that Ba (Ti _0.5 Co _0.5 ) ₂ Fe ₁₀ O ₁₉ M-type hexagonal ferrite (M-7) was used instead of (M-1). Table 7 shows the evaluation results of the sheet.

[ Reference Example 12 ]
The same procedure as in Example 1 was performed except that Ba (Ti · Mn) ₂ Fe ₁₀ O ₁₉ M-type hexagonal ferrite (M-8) was used instead of (M-1). Table 7 shows the evaluation results of the sheet.
[ Reference Example 13 ]
The same procedure as in Example 1 was performed except that Ba (Ti · Cu) ₂ Fe ₁₀ O ₁₉ M-type hexagonal ferrite (M-9) was used instead of (M-1). Table 7 shows the evaluation results of the sheet.
[ Reference Example 14 ]
Except for using _{Sr (Ti 0.6 Co 1.3 Zn 0.3} ) 2 Fe 10 O 19 (M-10) to (M-1) instead of were the same as in Example 1. Table 7 shows the evaluation results of the sheet.

[Example 15]
Except that the blending composition was (A-1) 30 g, Ba ₂ (Zn _0.7 ) ₂ Fe ₁₂ O ₂₂ Y-type hexagonal ferrite (Y-1) 120 g instead of (M-1), Example Same as 1. The composition of each component when the total amount is 100 parts by weight is (A-1) 20 parts by weight and (Y-1) 80 parts by weight. The evaluation results of the sheet are shown in Table 8.

[Example 16]
The same procedure as in Example 15 was performed except that Y-type hexagonal ferrite Ba ₂ (Zn _0.4 ) ₂ Fe ₁₂ O ₂₂ (Y-2) was used instead of (Y-1). The evaluation results of the sheet are shown in Table 8.
[Example 17]
The same procedure as in Example 15 was performed except that Y-type hexagonal ferrite Ba ₂ (Zn _1.3 ) ₂ Fe ₁₂ O ₂₂ (Y-3) was used instead of (Y-1). The evaluation results of the sheet are shown in Table 8.
[Example 18]
Except that instead of (M-1), Y-type hexagonal ferrite Ba ₂ (Zn _0.1 ) ₂ Fe ₁₂ O ₂₂ (Y-4) was used, the composition was changed to the values shown in Table 5, Example 1 was performed. The evaluation results of the sheet are shown in Table 8.
[Example 19]
Example 2 except that instead of (M-1), Y-type hexagonal ferrite Ba ₂ (Zn _1.5 ) ₂ Fe ₁₂ O ₂₂ (Y-5) was used and the composition was changed to the values shown in the table. As well as. The evaluation results of the sheet are shown in Table 8.

[Example 20]
The same procedure as in Example 1 was performed except that Z-type hexagonal ferrite Ba ₂ Co _1.1 Zn _0.5 Fe ₂₄ O ₄₁ (Z-1) was used instead of (M-1). Table 9 shows the evaluation results of the sheet.

[Example 21]
The same procedure as in Example 2 was performed except that Z-type hexagonal ferrite Ba ₂ Co _1.1 Zn _0.5 Fe ₂₄ O ₄₁ (Z-1) was used instead of (M-1). Table 9 shows the evaluation results of the sheet.
[Example 22]
The same procedure as in Example 1 was performed except that Z-type hexagonal ferrite Ba ₂ Co _0.5 Zn _0.2 Fe ₂₄ O ₄₁ (Z-2) was used instead of (Z-1). Table 9 shows the evaluation results of the sheet.
[Example 23]
The same procedure as in Example 1 was performed except that Z-type hexagonal ferrite Ba ₂ Co _0.5 Zn _0.9 Fe ₂₄ O ₄₁ (Z-3) was used instead of (Z-1). Table 9 shows the evaluation results of the sheet.
[Example 24]
The same procedure as in Example 1 was performed except that Z-type hexagonal ferrite Ba ₂ Co _1.9 Zn _0.2 Fe ₂₄ O ₄₁ (Z-4) was used instead of (Z-1). Table 9 shows the evaluation results of the sheet.

[ Reference Example 15 ]
The same procedure as in Example 2 was performed except that (A-2) was used instead of (A-1). The evaluation results of the sheet are shown in Table 10.
[ Reference Example 16 ]
The same procedure as in Example 1 was performed except that (A-3) was used instead of (A-1). The evaluation results of the sheet are shown in Table 10.
[ Reference Example 17 ]
The same procedure as in Example 2 was performed except that (A-4) was used instead of (A-1). The evaluation results of the sheet are shown in Table 10.
[Example 28]
The same procedure as in Example 1 was performed except that (A-3) was used instead of (A-1) and (Y-1) was used instead of (M-1). The evaluation results of the sheet are shown in Table 10.

[Example 29]
The same procedure as in Example 1 was performed except that (A-3) was used instead of (A-1) and (Z-1) was used instead of (M-1). The evaluation results of the sheet are shown in Table 10.
[ Reference Example 18 ]
The same procedure as in Example 3 was performed except that (A-4) was used instead of (A-1). The evaluation results of the sheet are shown in Table 10.
[ Reference Example 19 ]
The same procedure as in Example 1 was performed except that (A-5) was used instead of (A-1). The evaluation results of the sheet are shown in Table 10.
[ Reference Example 20 ]
The same procedure as in Example 2 was performed except that (A-6) was used instead of (A-1). The evaluation results of the sheet are shown in Table 10.

[ Reference Example 21 ]
Chlorinated polyethylene (A-7) was used instead of (A-1). The same procedure as in Example 1 was performed except that the initial temperature during kneading was 100 ° C., the final temperature reached 150 ° C., and the temperature during compression molding of the composition obtained by kneading was 180 ° C. Table 11 shows the evaluation results of the sheet.
[ Reference Example 22 ]
The same procedure as in Example 1 was performed except that acrylonitrile butadiene rubber (A-8) was used instead of (A-1). Table 11 shows the evaluation results of the sheet.
[ Reference Example 23 ]
The same procedure as in Example 1 was performed except that tetrafluoroethylene-ethylene copolymer (A-9) was used instead of (A-1). Table 11 shows the evaluation results of the sheet.
[ Reference Example 24 ]
It carried out similarly to Example 1 except having used perfluoroethylene polymer (A-10) instead of (A-1). Table 11 shows the evaluation results of the sheet.

[ Reference Example 25 ]
15 g of (A-11), 120 g of (M-1), and 15 g of magnesium hydroxide were kneaded at a resin temperature of 120 ° C., and the kneaded product was compression-pressed at 150 ° C. and 5 MPa for 3 minutes to obtain a sheet. Table 12 shows the evaluation results of the sheet.
[ Reference Example 26 ]
The same procedure as in Example 37 was performed, except that 20 g of (A-11) and 120 g of (M-1) were used. Table 12 shows the evaluation results of the sheet.

[ Reference Example 27 ]
The same operation as in Example 1 was performed except that the blending composition was (A-1) 20 g, (M-1) 120 g, and graphite 10 g. The composition of each component with respect to 100 parts by weight of the total amount of the resin composition is (A-1) 13 parts by weight, (M-1) 80 parts by weight, and graphite 7 parts by weight. The measurement result of thermal conductivity is 1.5 W / m. k, and the thermal conductivity of the sheet obtained in Example 1 is 0.8 W / m. The improvement effect was seen compared with K. Table 12 shows the evaluation results of the sheet.

[ Reference Example 28 ]
The same operation as in Example 1 was performed except that the blending composition was (A-1) 20 g, (M-1) 120 g, and alumina 10 g. The composition of each component with respect to 100 parts by weight of the total amount of the resin composition is (A-1) 13 parts by weight, (M-1) 80 parts by weight, and alumina 7 parts by weight. The measurement result of thermal conductivity is 1.4 W / m. k, and the thermal conductivity of the sheet obtained in Example 1 is 0.8 W / m. The improvement effect was seen compared with K. Table 12 shows the evaluation results of the sheet.

[ Reference Example 29 ]
The same operation as in Example 1 was performed except that the blending composition was (A-1) 30 g, (M-1) 90 g, and flat Sendust powder 30 g. The composition of each component with respect to 100 parts by weight of the total amount of the resin composition is (A-1) 20 parts by weight, (M-1) 60 parts by weight, and Sendust 20 parts by weight. In the method of radio wave absorption characteristics <Evaluation Method 2>, a peak derived from Sendust powder was observed at 0.8 GHz, and a peak derived from M-1 was observed at 10.1 GHz. Table 12 shows the evaluation results of the sheet.

[Comparative Example 1]
The same procedure as in Example 1 was performed except that Ni—Zn ferrite, which is cubic ferrite, was used instead of (M-1). Table 13 shows the sheet evaluation results.
[Comparative Example 2]
(A-1) 2 g and M type hexagonal ferrite (M-2) 148 g were charged into a kneader and kneading was attempted at 150 ° C., but uniform mixing was impossible. The composition of each component was (A-1) 1.3 parts by weight (M-2) 98.7 parts by weight with respect to 100 parts by weight of the total composition.
[Comparative Example 3]
The same procedure as in Comparative Example 2 was performed except that (Y-2) was used instead of (M-2). Even in this case, uniform mixing was not possible.
[Comparative Example 4]
The same procedure as in Comparative Example 2 was performed except that (Z-2) was used instead of (M-2). Even in this case, uniform mixing was not possible.

[Comparative Example 5]
The same procedure as in Example 1 was conducted except that the blending composition was (M-1) 90 g and (A-1) 60 g. The composition of each component was (A-1) 60 parts by weight (M-1) 40 parts by weight with respect to 100 parts by weight of the total composition. The evaluation results are shown in Table 13.
[Comparative Example 6]
The same procedure as in Comparative Example 5 was performed except that (Y-1) was used instead of (M-1). The evaluation results are shown in Table 13.
[Comparative Example 7]
The same operation as in Comparative Example 5 was performed except that (Z-1) was used instead of (M-1). The evaluation results are shown in Table 13.

  The sheet of the composition of the present invention effectively absorbs unnecessary electromagnetic waves in the high frequency region of 1 GHz or more generated in the circuit by being affixed inside an electronic device such as a personal computer or a mobile phone or a general electric product. Thus, malfunction of the device can be prevented, and radiation intensity of unnecessary electromagnetic waves to the outside of the device can be kept low. The composition of the present invention absorbs radar transmitted from an aircraft, a ship, and a passenger car, and prevents erroneous recognition of a target due to irregular reflection or erroneous reflection.

It is a figure showing the method of the softness | flexibility test (bending test) evaluated by this invention.

Claims (16)

In a resin composition containing hexagonal ferrite and a resin,
The hexagonal ferrite is Y-type ferrite or Z-type ferrite;
The Y-type ferrite metal is Zn,
The metal of the Z-type ferrite is Co or a combination of Co and Zn;
The resin is a fluororesin having a fluorine atom in the polymer molecular chain;
A resin composition comprising 50 to 98 parts by weight of hexagonal ferrite with respect to 100 parts by weight of the total amount of the resin composition.   The resin composition according to claim 1, comprising 90 to 95 parts by weight of the hexagonal ferrite. The fluororesin is tetrafluoroethylene, perfluoroalkoxyalkane, perfluoroethylene-propene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-chlorofluoroethylene copolymer The resin according to claim 1 or 2, which is at least one selected from a polymer, a tetrafluoroethylene-perfluoroidioxole copolymer, a polyvinylidene fluoride, and a tetrafluoroethylene-propylene copolymer. Composition.   The resin composition according to claim 3, wherein the fluororesin is a tetrafluoroethylene-propylene copolymer.   The resin composition according to claim 4, wherein the proportion of the number of propylene units in the total number of monomer units in the tetrafluoroethylene-propylene copolymer is 30 to 50%.   6. The resin composition according to claim 4, wherein the tetrafluoroethylene-propylene copolymer has a Mooney viscosity of 20 to 50 ML (1 + 10) 100 ° C. 6. 2. The resin composition according to claim 1, wherein the hexagonal ferrite is one or a mixture of two or more selected from the group consisting of Z-type and Y-type having the following general formula.
(Z-type) Ba ₃ M _β Fe ₂₄ O ₄₁
(Y type) Ba ₂ M ₂ Fe ₁₂ O ₂₂
In the formula, M is Co or a combination of Co and Zn in the Z type, Zn in the Y type, and part or all of Ba may be replaced with Sr.
In the Z-form formula, β is 0.1-20.   When the hexagonal ferrite includes Z-type, when the molar ratio of Z-type Fe component to M component is expressed as Fe component: M component = 24: β, the condition of 0.5 ≦ β ≦ 2.6 is satisfied. The resin composition according to claim 7. When the hexagonal ferrite includes Z-type, the Z-type is Ba ₃ Co _D Zn _E Fe ₂₄ O ₄₁ , and 0.4 ≦ D ≦ 2.0 and 0.1 ≦ E ≦ 1.0. The resin composition according to claim 7 or 8, wherein the resin composition is satisfied. When the hexagonal ferrite includes a Y type, the Y type is Ba ₂ (Zn _F ) ₂ Fe ₁₂ O ₂₂ and satisfies the condition of 0.35 ≦ F ≦ 1.35. The resin composition as described.   2 to 47 parts by weight of the resin, 50 to 95 parts by weight of the hexagonal ferrite, and soft magnetic ferrite, soft magnetic alloy, and thermal conductivity of 20 W / m · K with respect to 100 parts by weight of the total resin composition The mixture according to any one of claims 1 to 10, comprising 3 to 48 parts by weight of a mixture comprising one or a combination of two or more selected from the group consisting of the above highly heat-conductive inorganic substances and conductive substances. The resin composition as described.   A sheet comprising the resin composition according to claim 1.   The adhesive sheet which has an adhesion layer on the sheet | seat surface of Claim 12.   The coating material containing the resin composition in any one of Claims 1-11.   The sheet | seat for electromagnetic wave absorption which has the layer containing the coating material of Claim 14 on the sheet | seat surface of resin. The sheet according to any one of claims 12, 13, and 15, which is used for absorbing electromagnetic waves generated from a circuit of an electrical product or an electronic device.

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