JP2019106431A - Metal element-containing powder, mold, and method for manufacturing metal element-containing powder - Google Patents

Abstract

To provide metal element-containing powder suitable for fabrication of a mold small in magnetic loss.SOLUTION: Metal element-containing powder comprises: metal element-containing particles; and a cured product of a resin composition coating each metal element-containing particle. The resin composition contains an epoxy resin.SELECTED DRAWING: None

Description

  The present invention relates to a metal element-containing powder, a molded body, and a method of producing a metal element-containing powder.

  The metal element-containing powder containing a metal powder is used as a raw material of various industrial products such as an inductor, an electromagnetic wave shield, or a bond magnet according to various physical properties of the metal powder (see Patent Document 1 below).

Unexamined-Japanese-Patent No. 10-154613 gazette

  Magnetic powder is used for a magnetic core with which high frequency coils, such as a high frequency transformer, a reactor, a thyristor valve, a noise filter, and a choke coil, are provided, for example. The energy lost in the magnetic material in which alternating current magnetic flux is flowing is called magnetic loss. The magnetic core of the high frequency coil is required to have a small magnetic loss and a high magnetic flux density even in a high frequency region.

  The magnetic loss mainly consists of eddy current loss and hysteresis loss. Eddy current loss is closely related to the specific resistance of the magnetic core. The hysteresis loss is greatly affected by the distortion in the magnetic powder produced in the manufacturing process and subsequent processes of the magnetic powder. Eddy current loss is proportional to the square of the frequency of the AC electrical signal. Therefore, in order to reduce the magnetic loss in the high frequency region, it is important to reduce the eddy current loss. In order to reduce the eddy current loss, it is necessary to confine the eddy current to a small area. In order to confine the eddy current in a small area, it is necessary to form a magnetic core by compressing fine magnetic powder, and to isolate individual particles constituting the magnetic powder from one another.

  If the insulation between the individual particles making up the magnetic powder is insufficient, the eddy current losses are large. In order to produce a magnetic core having a small magnetic loss, it is necessary to cover the magnetic powder with an insulating layer having excellent insulating properties.

  An object of the present invention is to provide a metal element-containing powder suitable for producing a compact having a small magnetic loss, a molded body provided with the metal element-containing powder, and a method for producing the metal element-containing powder.

  The metal element-containing powder according to one aspect of the present invention includes metal element-containing particles and a cured product of a resin composition covering the metal element-containing particles, and the resin composition contains an epoxy resin.

  In the metal element-containing powder according to one aspect of the present invention, the resin composition may contain a phenol resin.

  In the metal element-containing powder according to one aspect of the present invention, the content of the cured product may be 0.5% by volume or more and 2.0% by volume or less.

  The metal element-containing powder according to one aspect of the present invention may be used for a magnetic core.

  The molded object concerning one side of the present invention is provided with the above-mentioned metallic element content powder.

  In the method for producing a metal element-containing powder according to one aspect of the present invention, a step of causing a solvent in which a resin composition is dissolved to adhere to the surface of metal element-containing particles, and removing the solvent adhering to the surface of metal element-containing particles The method includes the steps of: obtaining a metal element-containing particle covered with the resin composition; and curing the resin composition covering the metal element-containing particle.

  ADVANTAGE OF THE INVENTION According to this invention, the metal element containing powder suitable for preparation of the molded object with a small magnetic loss, the molded object provided with the said metal element containing powder, and the manufacturing method of the said metal element containing powder are provided.

  Hereinafter, preferred embodiments of the present invention will be described. However, the present invention is not limited to the following embodiment.

<Overview of powder containing metal element>
The metal element-containing powder according to the present embodiment includes a plurality of (multiple) metal element-containing particles and a cured product of a resin composition covering individual metal element-containing particles. That is, each of the plurality of particles constituting the metal element-containing powder has the metal element-containing particles and the cured product of the resin composition covering the surface of the metal element-containing particles. For example, a layer containing a cured product of the resin composition (a layer made of the cured product of the resin composition, etc.) may cover the surface of the metal element-containing particles. The resin composition contains an epoxy resin. That is, the cured product of the resin composition contains the cured product of the epoxy resin.

  Since the cured product of the resin composition containing an epoxy resin is excellent in the insulating property, the metal element-containing particles are covered with the cured product of the resin composition, so that the individual metal element-containing particles constituting the metal element-containing powder Are insulated from one another by the cured product of the resin composition. As a result, the eddy current loss of the compact formed of the metal element-containing powder is small, and the magnetic loss of the compact is small.

  The cured product of the resin composition may cover at least a part or the whole of the surface of the metal element-containing particle. The content of the cured product of the resin composition in the metal element-containing powder may be 0.5% by volume or more and 2.0% by volume or less. When the content of the cured product of the resin composition is 0.5% by volume or more, the surface of the metal element-containing particles is easily covered with the cured product of the resin composition, and the metal element-containing particles are sufficiently insulated. easy. As a result, the magnetic loss of the molded body tends to be small. When the content of the cured product of the resin composition is 2.0% by volume or less, the proportion of metal element-containing particles in the molded article tends to be sufficiently high, and the magnetic flux density of the molded article tends to be high.

  The average particle diameter of the entire metal element-containing particles covered with the cured product of the resin composition may be, for example, 1 μm or more and 500 μm or less. The average particle size of the metal element-containing particles may be, for example, 1 μm or more and 300 μm or less. Each average particle size may be measured, for example, by a particle size distribution analyzer. The average value of the thickness of the layer formed of the cured product of the resin composition covering the metal element-containing particles may be, for example, 0.01 μm or more and 10 μm or less. The average value of the layer thickness may be measured, for example, using a scanning electron microscope or a transmission electron microscope. Although the shape of each particle which comprises metal element containing powder is not limited, For example, it may be spherical shape, flat shape, prismatic shape, or needle shape.

  Depending on the composition or combination of the metal element-containing particles contained in the metal element-containing powder, various physical properties such as electromagnetic properties or thermal conductivity of the metal element-containing powder can be freely controlled, and the metal element-containing powder can be various industrial products Or it can be used for those raw materials. Industrial products manufactured using the metal element-containing powder may be, for example, automobiles, medical devices, electronic devices, electric devices, information communication devices, home appliances, audio devices, and general industrial devices. The metal element-containing powder may be used, for example, in a magnetic core. When the metal element-containing powder contains soft magnetic powder such as an Fe-Si-Cr alloy or ferrite as the metal element-containing particle, the metal element-containing powder is the above-mentioned inductor (for example, EMI filter) or transformer material (for example, magnetic core) May be used as When the metal element-containing powder contains a permanent magnet as the metal element-containing particle, the metal element-containing powder may be used as a raw material of a bonded magnet. When the metal element-containing powder contains iron and copper as the metal element-containing particles, a compact (for example, a sheet) formed of the metal element-containing powder may be used as an electromagnetic wave shield.

<Composition of Metal Element Containing Powder>

(Resin composition)
The resin composition contains at least a resin. The resin composition is a component that may include a resin, a curing agent, a curing accelerator, and an additive, and may be the remaining component (nonvolatile component) excluding the organic solvent and the metal element-containing particles. The additive is a component of the resin composition except the resin, the curing agent and the curing accelerator. The additive is, for example, a coupling agent or a flame retardant.

  The resin composition may contain a thermosetting resin. The thermosetting resin may contain, in addition to the epoxy resin, at least one selected from the group consisting of a phenol resin and a polyamideimide resin. If the resin composition comprises both an epoxy resin and a phenolic resin, the phenolic resin may function as a curing agent for the epoxy resin. The resin composition may contain a thermoplastic resin. The thermoplastic resin may be, for example, at least one selected from the group consisting of acrylic resin, polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyethylene terephthalate. The resin composition may contain both a thermosetting resin and a thermoplastic resin. The resin composition may contain a silicone resin.

  Since an epoxy resin is excellent in fluidity among thermosetting resins, a resin composition containing an epoxy resin can easily cover the surface of metal element-containing particles uniformly. The epoxy resin may be, for example, a resin having two or more epoxy groups in one molecule. Among epoxy resins, crystalline epoxy resins are preferred. Although the molecular weight of the crystalline epoxy resin is relatively low, the crystalline epoxy resin has a relatively high melting point and is excellent in fluidity.

  The epoxy resin is, for example, biphenyl type epoxy resin, stilbene type epoxy resin, diphenylmethane type epoxy resin, sulfur atom containing type epoxy resin, novolak type epoxy resin, dicyclopentadiene type epoxy resin, salicylaldehyde type epoxy resin, naphthols and phenol Copolymerized epoxy resin, epoxy compound of aralkyl type phenol resin, bisphenol type epoxy resin, glycidyl ether type epoxy resin of alcohols, glycidyl ether type epoxy resin of paraxylylene and / or metaxylylene modified phenolic resin, terpene modified phenolic resin Of glycidyl ether type epoxy resin, cyclopentadiene type epoxy resin, glycidyl ether type epoxy resin of polycyclic aromatic ring modified phenolic resin, naphthalene Containing phenolic resin glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidyl type or methyl glycidyl type epoxy resin, alicyclic type epoxy resin, halogenated phenol novolac type epoxy resin, ortho cresol novolac type epoxy resin, hydroquinone type epoxy It may be at least one selected from the group consisting of a resin, a trimethylolpropane type epoxy resin, and a linear aliphatic epoxy resin obtained by oxidizing an olefin bond with a peracid such as peracetic acid.

  The crystalline epoxy resin (highly crystalline epoxy resin) may be, for example, at least one selected from the group consisting of a hydroquinone epoxy resin, a bisphenol epoxy resin, a thioether epoxy resin, and a biphenyl epoxy resin. Commercial products of crystalline epoxy resin include, for example, Epiclon 860, Epiclon 1050, Epiclon 1055, Epiclon 2050, Epiclon 3050, Epiclon 4050, Epiclon 7050, Epiclon HM-091, Epiclon HM-101, Epiclon N-730A, Epiclon N -740, epiclone N-770, epiclone N-775, epiclone N-865, epiclone HP-4032D, epiclone HP-7200L, epiclone HP-7200, epiclone HP-7200 H, epiclone HP-7200 HH, epiclone HP-7200 HHH, epiclone HP -4700, Epiclon HP-4710, Epiclon HP-4770, Epiclon HP-5000, Epiclon HP-6000, and N500P-2 (above, Trade name of IC Corporation), NC-3000, NC-3000-L, NC-3000-H, NC-3100, CER-3000-L, NC-2000-L, XD-1000, NC-7000-L , NC-7300-L, EPPN-501H, EPPN-501HY, EPPN-502H, EOCN-1020, EOCN-102S, EOCN-103S, EOCN-104S, CER-1020, EPPN-201, BREN-S, BREN-10S (Above, trade name of Nippon Kayaku Co., Ltd.), YX-4000, YX-4000H, YL4121H, and YX-8800 (above, trade name of Mitsubishi Chemical Co., Ltd.) You may

  The resin composition may contain one of the above epoxy resins. The resin composition may contain a plurality of epoxy resins among the above. It is preferable that a resin composition contains both a biphenyl type epoxy resin (YX-4000H) and an ortho cresol novolak type epoxy resin (N500P-2) among said epoxy resins.

  The curing agent is classified into a curing agent which cures an epoxy resin in a range from low temperature to room temperature, and a heat curing type curing agent which cures an epoxy resin with heating. Examples of curing agents that cure epoxy resins in the range from low temperature to room temperature include aliphatic polyamines, polyaminoamides, polymercaptans and the like. The heat-curable curing agent is, for example, an aromatic polyamine, an acid anhydride, a phenol novolac resin, and dicyandiamide (DICY).

  When a curing agent for curing the epoxy resin in the range from low temperature to room temperature is used, the glass transition point of the cured product of the epoxy resin is low, and the cured product of the epoxy resin tends to be soft. On the other hand, from the viewpoint of improving the heat resistance of the cured product of the epoxy resin, the curing agent may preferably be a heat curing type curing agent, more preferably a phenol resin, and still more preferably a phenol novolac resin. In particular, by using a phenol novolac resin as a curing agent, a cured product of an epoxy resin having a high glass transition temperature can be easily obtained. As a result, the heat resistance and mechanical strength of the cured product of the resin composition (epoxy resin) covering the metal element-containing particles can be easily improved.

  The phenolic resin is, for example, an aralkyl type phenolic resin, a dicyclopentadiene type phenolic resin, a salicylaldehyde type phenolic resin, a novolak type phenolic resin, a copolymer type phenolic resin of benzaldehyde type phenol and an aralkyl type phenol, paraxylylene and / or metaxylylene modified From the group consisting of phenolic resin, melamine modified phenolic resin, terpene modified phenolic resin, dicyclopentadiene type naphthol resin, cyclopentadiene modified phenolic resin, polycyclic aromatic ring modified phenolic resin, biphenyl type phenolic resin, and triphenylmethane type phenolic resin It may be at least one selected. The phenolic resin may be a copolymer composed of two or more of the above. As a commercial item of phenol resin, for example, Tamanor 758 or Tamanor 759 manufactured by Arakawa Chemical Industries, Ltd., HP-850N manufactured by Hitachi Chemical Co., Ltd., or the like may be used.

  The phenol novolac resin may be, for example, a resin obtained by condensation or cocondensation of phenols and / or naphthols with aldehydes under an acidic catalyst. The phenols constituting the phenol novolac resin may be, for example, at least one selected from the group consisting of phenol, cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol and aminophenol. The naphthols constituting the phenol novolac resin may be, for example, at least one selected from the group consisting of α-naphthol, β-naphthol and dihydroxynaphthalene. The aldehydes constituting the phenol novolac resin may be, for example, at least one selected from the group consisting of formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde and salicylaldehyde.

  The curing agent may be, for example, a compound having two phenolic hydroxyl groups in one molecule. The compound having two phenolic hydroxyl groups in one molecule may be, for example, at least one selected from the group consisting of resorcin, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenol.

  The resin composition may contain one of the above phenolic resins. The resin composition may comprise a plurality of phenolic resins of the above. The resin composition may contain one of the above curing agents. The resin composition may contain a plurality of curing agents among the above.

  The ratio of the active group (phenolic OH group) in the curing agent that reacts with the epoxy group in the epoxy resin is preferably 0.5 to 1.5 equivalents, more preferably one equivalent to the epoxy group in the epoxy resin. May be 0.8 to 1.2 equivalents, more preferably 0.9 to 1.1 equivalents. When the ratio of active groups in the curing agent is less than 0.5 equivalent, the amount of OH per unit weight of the epoxy resin after curing decreases, and the curing rate of the resin composition (epoxy resin) decreases. If the ratio of active groups in the curing agent is less than 0.5 equivalent, the glass transition temperature of the resulting cured product may be lowered, or sufficient mechanical strength of the cured product may not be obtained. On the other hand, when the ratio of active groups in the curing agent exceeds 1.5 equivalents, the mechanical strength of the cured product tends to decrease. However, even when the ratio of active groups in the curing agent is out of the above range, the effects according to the present invention can be obtained.

  The curing accelerator is not limited as long as it is, for example, a composition that reacts with the epoxy resin to accelerate the curing of the epoxy resin. The curing accelerator may be, for example, an alkyl group-substituted imidazole or an imidazole such as benzimidazole. The resin composition may comprise one type of curing accelerator. The resin composition may be provided with a plurality of curing accelerators. By containing a curing accelerator as a component of the resin composition, the mechanical strength of the cured product of the resin composition covering the metal element-containing particles can be easily improved.

  The compounding quantity of a hardening accelerator should just be an quantity which the hardening acceleration effect is acquired, and is not specifically limited. However, from the viewpoint of improving the curability and flowability of the resin composition, the compounding amount of the curing accelerator is preferably 0.1 to 30 parts by mass, more preferably 1 to 100 parts by mass of the epoxy resin. -15 mass parts may be sufficient. It is preferable that content of a hardening accelerator is 0.001 mass part or more and 5 mass parts or less with respect to the sum total of the mass of an epoxy resin and a hardening agent (for example, phenol resin). When the content of the curing accelerator is less than 0.001 parts by mass, it is difficult to obtain a sufficient curing acceleration effect. When content of a hardening accelerator exceeds 5 mass parts, the mechanical strength of the hardened | cured material of the resin composition which covers metal element containing particle | grains falls easily. However, even when the compounding amount and the content of the curing accelerator are out of the above range, the effect according to the present invention can be obtained.

  The coupling agent improves the adhesion between the resin composition and the metal element-containing particles, and improves the flexibility and mechanical strength of the particles constituting the metal element-containing powder. The coupling agent may be, for example, at least one selected from the group consisting of silane compounds (silane coupling agents), titanium compounds, aluminum compounds (aluminum chelates), and aluminum / zirconium compounds. The silane coupling agent may be, for example, at least one selected from the group consisting of epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, acid anhydride silane and vinylsilane. In particular, aminophenyl-based silane coupling agents are preferred. The resin composition may include one of the above coupling agents, and may include a plurality of the above coupling agents.

  The resin composition may contain a flame retardant because of the environmental safety, recyclability, moldability and low cost of the metal element-containing powder. The flame retardant is, for example, at least one selected from the group consisting of bromine flame retardants, stalk flame retardants, hydrated metal compound flame retardants, silicone flame retardants, nitrogen containing compounds, hindered amine compounds, organic metal compounds and aromatic engineering plastics It may be. The resin composition may include one of the above-described flame retardants, and may include a plurality of the above-described flame retardants.

(Metal element containing particles)
The metal element-containing particle may contain, for example, at least one selected from the group consisting of a single metal, an alloy and a metal compound. The metal element-containing particles may be made of, for example, at least one selected from the group consisting of simple metals, alloys, and metal compounds. The alloy may include at least one selected from the group consisting of solid solution, eutectic and intermetallic compounds. The alloy may be, for example, stainless steel (Fe-Cr based alloy, Fe-Ni-Cr based alloy, etc.). The metal compound may be, for example, an oxide such as ferrite. The metal element-containing particles may contain one or more metal elements. The metal element contained in the metal element-containing particle may be, for example, a base metal element, a noble metal element, a transition metal element, or a rare earth element. The metal element contained in the metal element-containing powder is, for example, iron (Fe), copper (Cu), titanium (Ti), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), aluminum ( Al), tin (Sn), chromium (Cr), barium (Ba), strontium (Sr), lead (Pb), silver (Ag), praseodymium (Pr), neodymium (Nd), samarium (Sm) and dysprosium ( It may be at least one selected from the group consisting of Dy). The metal element-containing particle may contain an element other than the metal element. The metal element-containing particles may contain, for example, oxygen (O), beryllium (Be), phosphorus (P), boron (B), or silicon (Si). The metal element-containing particles may be magnetic powder. The metal element-containing particles may be a soft magnetic alloy or a ferromagnetic alloy. The metal element-containing particles are, for example, Fe-Si alloys, Fe-Si-Al alloys (Sendust), Fe-Ni alloys (Permalloy), Fe-Cu-Ni alloys (Permalloy), Fe-Co alloys (Permendur), Fe-Cr-Si alloy (electromagnetic stainless steel), Nd-Fe-B alloy (rare earth magnet), Sm-Fe-N alloy (rare earth magnet), Al-Ni-Co alloy It may be at least one selected from the group consisting of (alnico magnet) and ferrite. The ferrite may be, for example, spinel ferrite, hexagonal ferrite, or garnet ferrite. The metal element-containing particles may be a copper alloy such as a Cu-Sn alloy, a Cu-Sn-P alloy, a Cu-Ni alloy, or a Cu-Be alloy. The metal element-containing particle may contain one of the above elements and compositions, and may contain a plurality of the above elements and compositions.

  The metal element-containing particles may be Fe alone. The metal element-containing particles may be an iron-containing alloy (Fe-based alloy). The Fe-based alloy may be, for example, an Fe-Si-Cr-based alloy or an Nd-Fe-B-based alloy. When the metal element-containing powder contains at least one of Fe and Fe-based alloy as metal element-containing particles, it is easy to produce a molded body having a high space factor and excellent in magnetic characteristics from the metal element-containing powder . The metal element-containing particles may be Fe amorphous alloy. Commercial products of Fe amorphous alloy powder include, for example, AW2-08, KUAMET-6B2 (all trade names of Epson Atomics Co., Ltd., DAP MS3, DAP MS7, DAP MSA10, DAP PB, DAP PC, DAP MKV 49). , DAP 410L, DAP 430L, DAP HYB series (all trade names of Daido Steel Co., Ltd.), MH45D, MH28D, MH25D, and MH20D (all trade names of Kobe Steel, Ltd.) Or at least one of them may be used.

  The shape of the metal element-containing particle is not particularly limited. The individual metal element-containing particles may be, for example, spherical, flat or needle-like. The metal element-containing powder may contain plural types of metal element-containing particles having different average particle sizes.

<Method of producing metal element-containing powder>
The method for producing the metal element-containing powder according to the present embodiment comprises: attaching a solvent in which the resin composition is dissolved to the surface of the metal element-containing particles; and removing the solvent adhering to the surface of the metal element-containing particles. And removing the metal element-containing particles covered with the resin composition, and curing the resin composition covering the metal element-containing particles. A curing step may be performed after the removal step. The removal step and the curing step may be performed simultaneously. The method of producing the metal element-containing powder may include another step in addition to the adhesion step, the removal step, and the curing step. For example, the method for producing the metal element-containing powder may further include a pulverizing step of grinding an aggregate formed from the metal element-containing powder after the curing step. The details of each step may be, for example, as follows. However, each process is not limited to the following cases.

  In the adhesion step, first, the resin composition is dissolved in a solvent to obtain a surface treatment liquid. The solvent is not particularly limited as long as it is a liquid that dissolves the resin composition. The solvent is, for example, at least one selected from the group consisting of acetone, N-methyl pyrrolidinone (N-methyl-2-pyrrolidone), γ-butyrolactone, dimethylformamide, dimethyl sulfoxide, methyl ethyl ketone, methyl isobutyl ketone, toluene and xylene. You may The solvent is preferably acetone. When the solvent is acetone, acetone is easy to dry. Therefore, the solvent can be removed from the surface treatment solution by drying the surface treatment solution attached to the surface of the metal element-containing particles in the removal step described later. Subsequently, the metal element-containing particles and the surface treatment liquid are mixed to obtain a mixed liquid. In the liquid mixture, the metal element-containing particles and the resin composition are in contact with each other, and the resin composition covers the surface of the metal element-containing particles. The content of the cured product of the resin composition in the metal element-containing powder can be adjusted by the content of the resin composition in the surface treatment liquid.

  In the removing step, the mixed solution is separated by filtration to obtain metal element-containing particles with the surface treatment solution attached to the surface. Subsequently, the solvent is sufficiently removed from the surface treatment liquid attached to the surface of the metal element-containing particles. When the resin composition contained in the surface treatment liquid adheres to the surface of the metal element-containing particles along with the removal of the solvent, the metal element-containing particles covered with the resin composition can be obtained. The resin composition may be attached to the entire surface of the metal element-containing particle, or may be attached to only a part of the surface of the metal element-containing particle. The method for removing the solvent from the surface treatment solution is not particularly limited. For example, the solvent can be removed from the surface treatment liquid by drying the surface treatment liquid. The drying method may be, for example, air drying.

  In the curing step, the resin composition is cured by heating the metal element-containing particles covered with the resin composition. The heating temperature may be 150 ° C. or more and 250 ° C. or less. When the heating temperature is 150 ° C. or less, the curing reaction tends to be insufficient. When the heating temperature is 250 ° C. or more, the resin contained in the resin composition is likely to be deteriorated and the metal element-containing particles are easily oxidized. The heating time may be 3 minutes or more and 2 hours or less. When the heating time is 3 minutes or less, the curing reaction tends to be insufficient. When the heating time is 2 hours or more, the production efficiency of the metal element-containing powder tends to decrease.

  The method for producing the metal element-containing powder is not limited to the above method. For example, in the adhesion step, the surface treatment liquid may be added to the metal element-containing particles (powder of the particles), and the powder and the surface treatment liquid may be mixed to obtain a mixture. In the removal step, the solvent may be removed from the mixture by drying the mixture without filtering. Drying of the mixture and curing of the resin composition may be performed simultaneously or sequentially by heating the mixture.

<Compound>
The compound which concerns on this embodiment contains the said metal element containing powder | flour, and a resin composition (resin composition distinguished from the resin composition which covers metal element containing particle | grains). Components other than the hardened | cured material of the resin composition which covers the surface of a metal element containing particle among the resin compositions contained in a compound are described with the resin composition for compounds. The compounding resin composition may cover at least a part or all of the individual particles constituting the metal element-containing powder. The compounding resin composition may be attached to the surface of the individual particles constituting the metal element-containing powder. The compounding resin composition may be attached to the entire surface of the particle, or may be attached to only a part of the surface of the particle. The compound may comprise an uncured compound resin composition and a metal element-containing powder. The compound may comprise a semi-cured product of a compounding resin composition (for example, a B-stage compounding resin composition) and a metal element-containing powder. The compound may be a powder (compound powder).

(Resin composition for compound)
The compounding resin composition contains at least a resin. The resin composition for compounding is a component that can include a resin, a curing agent, a curing accelerator, and an additive, and is a resin composition that covers an organic solvent and metal element-containing powder (metal element-containing particles and metal element-containing particles (Non-volatile component) except for the cured product of An additive is a component of the remainder except resin, a hardening | curing agent, and a hardening accelerator among resin compositions for compounds. The additive is, for example, a coupling agent or a flame retardant. The compounding resin composition may contain a wax as an additive. As described below, the compound may be formed from the metal element-containing powder and the resin composition for compounding.

  The resin composition for compounding has a function as a binder (binder) of metal element-containing powder and imparts mechanical strength to a molded body formed from the compound. For example, when the compound resin composition for compounding contained in the compound is molded at high pressure using a mold, it is filled between the particles constituting the metal element-containing powder to bind the particles to each other. By curing the compounding resin composition in the molded body, the cured product of the compounding resin composition binds particles forming the metal element-containing powder more firmly, and the mechanical strength of the molded body is increased. improves.

  The resin composition for compounding may contain a thermosetting resin. The thermosetting resin may be, for example, at least one selected from the group consisting of an epoxy resin, a phenol resin, and a polyamideimide resin. When the compounding resin composition contains both an epoxy resin and a phenol resin, the phenol resin may function as a curing agent for the epoxy resin. The compounding resin composition may contain a thermoplastic resin. The thermoplastic resin may be, for example, at least one selected from the group consisting of acrylic resin, polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyethylene terephthalate. The compounding resin composition may contain both a thermosetting resin and a thermoplastic resin. The resin composition for compounding may contain a silicone resin.

  The content of the resin composition for compounding in the compound may be 0.2 to 10% by mass with respect to the mass of the entire compound (the total of the mass of the metal element-containing powder and the resin composition for compounding), more preferably May be 4 to 6% by mass.

  Since the epoxy resin is excellent in fluidity among thermosetting resins, the resin composition for compounding preferably contains an epoxy resin. The epoxy resin may be, for example, a resin having two or more epoxy groups in one molecule. Among epoxy resins, crystalline epoxy resins are preferred. Although the molecular weight of the crystalline epoxy resin is relatively low, the crystalline epoxy resin has a relatively high melting point and is excellent in fluidity.

  The epoxy resin may be at least one of the above epoxy resins. The crystalline epoxy resin may be at least one of the crystalline epoxy resins described above.

  The resin composition for compounding may contain one of the above epoxy resins. The resin composition for compounding may contain two or more of the above-described epoxy resins. It is preferable that the resin composition for compound contains both a biphenyl type epoxy resin (YX-4000H) and an ortho cresol novolak type epoxy resin (N500P-2) among said epoxy resins.

  The curing agent is classified into a curing agent which cures an epoxy resin in a range from low temperature to room temperature, and a heat curing type curing agent which cures an epoxy resin with heating. Examples of curing agents that cure epoxy resins in the range from low temperature to room temperature include aliphatic polyamines, polyaminoamides, polymercaptans and the like. The heat-curable curing agent is, for example, an aromatic polyamine, an acid anhydride, a phenol novolac resin, and dicyandiamide (DICY).

  When a curing agent for curing the epoxy resin in the range from low temperature to room temperature is used, the glass transition point of the cured product of the epoxy resin is low, and the cured product of the epoxy resin tends to be soft. As a result, the molded body formed from the compound also tends to be soft. On the other hand, from the viewpoint of improving the heat resistance of the molded product, the curing agent may preferably be a heat-curing type curing agent, more preferably a phenol resin, and still more preferably a phenol novolac resin. In particular, by using a phenol novolac resin as a curing agent, a cured product of an epoxy resin having a high glass transition temperature can be easily obtained. As a result, the heat resistance and mechanical strength of the molded body can be easily improved.

  The phenolic resin may be at least one of the above phenolic resins. The conphenol novolac resin may be at least one of the above mentioned phenolic novolac resins.

  The curing agent may be, for example, a compound having two phenolic hydroxyl groups in one molecule. The compound having two phenolic hydroxyl groups in one molecule may be, for example, at least one selected from the group consisting of resorcin, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenol.

  The resin composition for compounding may contain one of the above-mentioned phenol resins. The resin composition for compounding may be provided with a plurality of phenolic resins among the above. The compounding resin composition may contain one of the above-mentioned curing agents. The resin composition for compounding may contain a plurality of curing agents among the above.

  The ratio of the active group (phenolic OH group) in the curing agent that reacts with the epoxy group in the epoxy resin is preferably 0.5 to 1.5 equivalents, more preferably one equivalent to the epoxy group in the epoxy resin. May be 0.9 to 1.4 equivalents, more preferably 1.0 to 1.2 equivalents. When the ratio of active groups in the curing agent is less than 0.5 equivalent, the amount of OH per unit weight of the epoxy resin after curing decreases, and the curing rate of the resin composition for compounding (epoxy resin) decreases. If the ratio of active groups in the curing agent is less than 0.5 equivalent, the glass transition temperature of the resulting cured product may be lowered, or a sufficient elastic modulus of the cured product may not be obtained. On the other hand, when the ratio of active groups in the curing agent exceeds 1.5 equivalents, the mechanical strength after curing of the molded body formed from the compound tends to decrease. However, even when the ratio of active groups in the curing agent is out of the above range, the effects according to the present invention can be obtained.

  The curing accelerator is not limited as long as it is, for example, a composition that reacts with the epoxy resin to accelerate the curing of the epoxy resin. The curing accelerator may be, for example, an alkyl group-substituted imidazole or an imidazole such as benzimidazole. The compounding resin composition may comprise one type of curing accelerator. The compounding resin composition may be provided with a plurality of curing accelerators. By containing a curing accelerator as a component of the resin composition for compounding, the moldability and releasability of the compound can be easily improved. In addition, by containing a curing accelerator as a component of the resin composition for compounding, mechanical strength of a molded article (for example, an electronic component) manufactured using the compound is improved, or in a high temperature and high humidity environment. The storage stability of the compound is improved.

  The compounding quantity of a hardening accelerator should just be an quantity which the hardening acceleration effect is acquired, and is not specifically limited. However, from the viewpoint of improving the curability and fluidity of the compound resin composition during moisture absorption, the compounding amount of the curing accelerator is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the epoxy resin. More preferably, it may be 1 to 15 parts by mass. It is preferable that content of a hardening accelerator is 0.001 mass part or more and 5 mass parts or less with respect to the sum total of the mass of an epoxy resin and a hardening agent (for example, phenol resin). When the compounding quantity of a hardening accelerator is less than 0.1 mass part, sufficient hardening acceleration effect is hard to be acquired. If the amount of the curing accelerator exceeds 30 parts by mass, the storage stability of the compound tends to be reduced. However, even when the compounding amount and the content of the curing accelerator are out of the above range, the effect according to the present invention can be obtained.

  The coupling agent improves the adhesion between the compounding resin composition and the particles constituting the metal element-containing powder, and improves the flexibility and mechanical strength of the molded body formed from the compound. The coupling agent may be at least one of the coupling agents described above. As the coupling agent, aminophenyl-based silane coupling agents are preferred. The compound may include one of the above coupling agents, and may include more than one of the above coupling agents.

  The compounds may contain flame retardants because of their environmental safety, recyclability, moldability and low cost. The flame retardant may be at least one of the above flame retardants. The compound may include one of the above-described flame retardants, and may include more than one of the above-described flame retardants.

  The wax may be at least one of fatty acids such as higher fatty acids and fatty acid esters. The compound may comprise more than one wax. The wax preferably contains a fatty acid from the viewpoint of easily improving the flowability of the compound.

<Method of manufacturing compound>
Although the manufacturing method of a compound is not specifically limited, For example, it may be as follows. First, a resin solution is prepared by uniformly stirring and mixing a resin, metal element-containing powder and an organic solvent. In other words, a resin solution is prepared by mixing the above-described resin composition for compounding, metal element-containing powder and an organic solvent. The resin solution may contain a curing agent. The resin solution may contain a curing accelerator. The resin solution may contain additives such as coupling agents, flow aids, flame retardants, and lubricants. The organic solvent is not particularly limited as long as it is a liquid that dissolves the compounding resin composition. The organic solvent is, for example, at least one selected from the group consisting of acetone, N-methyl pyrrolidinone (N-methyl-2-pyrrolidone), γ-butyrolactone, dimethylformamide, dimethyl sulfoxide, methyl ethyl ketone, methyl isobutyl ketone, toluene and xylene. May be there. Subsequently, the compound is obtained by sufficiently removing the organic solvent from the resin solution. With the removal of the organic solvent, the resin composition for compounding adheres to the surfaces of the individual particles constituting the metal element-containing powder. The compounding resin composition may be attached to the entire surface of the particle, or may be attached to only a part of the surface of the particle. The method for removing the organic solvent from the resin solution is not particularly limited. For example, the organic solvent can be removed from the resin solution by drying the resin solution. The method of drying the resin solution may be, for example, vacuum drying. A lubricant may be added to the compound obtained above in order to reduce mold damage in the second step described later. The lubricant is not particularly limited. The lubricant may be, for example, at least one selected from the group consisting of metal soaps and wax-based lubricants. Also, in order to reduce damage to the mold in the second step, a lubricant is dispersed in a suitable dispersion medium to prepare a dispersion, and the dispersion is used as a wall in the mold die (wall in contact with the punch) And the applied dispersion may be dried. A powdery compound is obtained by the above method.

<Molded body>
The molded object which concerns on this embodiment is equipped with the said metal element containing powder. The molded body may consist of only the metal element-containing powder, and may have other components in addition to the metal element-containing powder. The molded body may include the metal element-containing powder and the resin composition for compounding. The molded product is an uncured resin composition for compounding, a semi-cured product of the resin composition for compounding (resin composition for compounding for B stage), and a cured product of the resin composition for compounding (resin composition for compounding for C stage At least one selected from the group consisting of The molded body may be a cured product of the above compound. The molded object comprised from the hardened | cured material of a compound may be equipped with metal element containing powder | flour and the hardened | cured material of the resin composition for compounds which mutually bond metal element containing powder | flour.

<Method of manufacturing molded body>
The method for producing a molded article provided with the metal element-containing powder according to the present embodiment may include the step of pressing the metal element-containing powder in a mold. The method for producing a molded body may include only the step of pressing the metal element-containing powder in a mold, and may include other steps in addition to the step. The manufacturing method of the molded object comprised from the hardened | cured material of the said compound may be equipped with a 1st process, a 2nd process, and a 3rd process. Below, the detail of each process is demonstrated.

  In the first step, a compound is produced by the method described above.

  In the second step, the compound is pressurized in a mold to obtain a molded body (a molded body of B-stage). Here, the resin composition for compounding is filled between the individual particles constituting the metal element-containing powder. And the resin composition for compounding functions as a binder (binder), and mutually binds particles which comprise metal element containing powder. The higher the pressure exerted on the compound, the higher the density of the molded body, and the higher the mechanical strength of the molded body. When manufacturing a bonded magnet, the higher the pressure exerted on the compound, the higher the magnetic flux density of the bonded magnet tends to be, and the higher the mechanical strength of the bonded magnet. The pressure exerted on the compound may be, for example, preferably 500 MPa or more and 2500 MPa or less, more preferably 1400 MPa or more and 2000 MPa or less. When the pressure exerted on the compound is within the above range, the mass productivity of the molded product is likely to be improved and the life of the mold is likely to be extended.

  In the third step, the compact is cured by heat treatment to obtain a C-staged compact. The temperature of the heat treatment may be a temperature at which the compounding resin composition in the molded body is sufficiently cured. The temperature of the heat treatment may be, for example, preferably 150 ° C. or more and 300 ° C. or less, more preferably 175 ° C. or more and 250 ° C. or less. In order to suppress the oxidation of the metal element-containing powder (the metal element-containing particles) in the molded body, the heat treatment is preferably performed in an inert atmosphere. When the heat treatment temperature exceeds 300 ° C., the metal element-containing powder is oxidized or the cured resin product is degraded by a trace amount of oxygen inevitably contained in the atmosphere of the heat treatment. In order to sufficiently cure the resin composition for compounding while suppressing the oxidation of the metal element-containing powder and the deterioration of the cured resin, the heat treatment temperature holding time is preferably several minutes to 4 hours, more preferably It may be 5 minutes or more and 1 hour or less.

  Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited by these examples.

(Preparation of surface treatment solution)
[Surface treatment solution 1]
In a 300 mL polycup (polypropylene cup), 0.65 g of an epoxy resin, 0.34 g of a phenol resin, 0.01 g of a curing accelerator, and 99 g of acetone (manufactured by Wako Pure Chemical Industries, Ltd.) were placed. As epoxy resin, YX-4000H manufactured by Japan Epoxy Resins Co., Ltd. was used. The epoxy equivalent of the epoxy resin was 196 g / eq. As phenolic resin, HP-850N made by Hitachi Chemical Co., Ltd. was used. The hydroxyl group equivalent of the phenol resin was 103 g / eq. C11 Z-CN manufactured by Shikoku Kasei Kogyo Co., Ltd. was used as a curing accelerator. The surface treatment solution 1 was obtained by stirring and mixing the raw materials in the polycup. The part of the surface treatment solution 1 excluding the solvent (acetone and the like) corresponds to the resin composition, and the total content of the epoxy resin, the phenol resin, and the curing accelerator in the surface treatment solution 1 A unit: mass%) is shown in following Table 1. In Table 1, "solution concentration" means the sum total of content of the epoxy resin in a surface treatment liquid, a phenol resin, and a hardening accelerator.

[Surface treatment solution 2 to 7]
In preparation of surface treatment solutions 2 to 7, each raw material was placed in a polycup so that the composition of each surface treatment solution had the composition shown in Table 1 below. Surface treatment solutions 2 to 7 were individually prepared by the same method as the surface treatment solution 1 except for the above matters.
HP-4032D in the following Table 1 is a product "Epiclon HP-4032D" manufactured by DIC Corporation and is a naphthalene type epoxy resin (1,6-bis (2,3-epoxypropan-1-yloxy) naphthalene). is there.

Example 1
[Preparation of metal element-containing powder]
In 300 mL of polybin (polyethylene bottle), 60.0 g of carbonyl iron powder (pure iron powder) was placed as metal element-containing particles. As carbonyl iron powder, SQ made by BASF Japan Ltd. was used. 80.0 g of the surface treatment solution 1 was placed in a poly bottle. The mixture was obtained by stirring and mixing the raw materials in the polybin for 30 minutes. The mixed solution was filtered using filter paper to obtain a mixed powder containing the metal element-containing particles covered with the surface treatment solution 1. The mixed powder was allowed to dry overnight. The drying method was air drying. The dried mixed powder was transferred to a metal vat and placed in an oven preheated to 180 ° C. The mixed powder was dried by heating the mixed powder in an oven to cure the resin composition. The drying temperature was 180 ° C. The drying time was 1 hour. The metal element containing powder was obtained by the above method. The metal element-containing powder was provided with a plurality of metal element-containing particles and a cured product of a resin composition covering the surfaces of the individual metal element-containing particles.

[Measurement of Content of Cured Product of Resin Composition]
The mass m ₁ of carbon contained in the metal element-containing powder was measured using a carbon / sulfur analyzer. As carbon / sulfur analyzer, CS744 manufactured by LECO Japan Ltd. was used. In the same manner as described above, the mass m ₀ of the carbon contained in the metal element-containing particles prior to mixing with the surface treatment solution was measured. It was calculated difference _m 1 -m ₀ of m ₁ and _{m 0.} m ₁ -m ₀ corresponds to the mass m _A of carbon contained in the cured product of the resin composition adhering to the surface of the metal element-containing particle. The m _A, divided by the mass M of the entire metal-element-containing powder used in the measurement, the content of carbon in the entire metal-element-containing powder M _{A (unit:} mass%) was calculated. M _A equals 100 × m _A / M. If the weight average molecular weight of the cured product of the resin composition is denoted by M _C, based on the molecular structure of the cured product of the resin composition, the ratio of the mass m _C of carbon in one molecule of the cured product of the resin composition M _B I asked for. M _B is equal to m _C / M _C. By dividing M _A by M _B , the content M _D (unit: mass%) of the cured product of the resin composition contained in the metal element-containing powder was calculated. M _D is equal to M _A / M _B. From the M _D, and density (specific gravity) d _R of the cured product of the resin composition, and the density d _M of the metal element-containing powder, the content of the cured product of the resin composition contained in the metal-element-containing powder [C] ( Unit: volume%) was calculated. [C] is equal to M _D · d _M / d _R. [C] of Example 1 is shown in Table 2 below.

[Preparation of toroidal]
The metal element-containing powder of Example 1 was loaded into a mold. The metal element-containing powder in the mold was pressurized using a hydraulic press to obtain a toroidal (molded body). The pressure applied to the metal element-containing powder was 300 MPa (3 ton / cm ² ). The toroidal shape had an outer diameter of 20 mm, an inner diameter of 12 mm, and a length of 2 mm.

[Measurement of magnetic loss]
The toroidal magnetic loss of Example 1 was measured using a B-H analyzer. As B-H analyzer, SY-8258 manufactured by Iwasaki Tsushinki Co., Ltd. was used. In the toroidal, a copper wire with a diameter of 0.4 mm was wound 5 turns on the excitation side, and a 0.26 mm copper wire was wound 5 turns on the detection side. The magnetic loss at a frequency of 1000 kHz was measured at an excitation magnetic flux density of 10 mT. The magnetic loss Pcv (unit: kW / m ³ ) of Example 1 is shown in Table 2 below.

[Measurement of toroidal density]
The toroidal density of Example 1 was measured by the Archimedes method. The density (unit: Mg / m ³ = 10 ⁶ g / m ³ ) of Example 1 is shown in Table 2 below.

(Examples 2 to 7)
In preparation of the metal element containing powder of each Example 2-7, the surface treatment liquid shown by following Table 2 was used. The metal element-containing powders of Examples 2 to 7 were individually manufactured by the same method as Example 1 except for the above matters.

  Each [C] of Examples 2 to 7 was measured in the same manner as Example 1. In the same manner as in Example 1, toroids of Examples 2 to 7 were individually produced. In the same manner as in Example 1, the magnetic loss and toroidal density in each of Examples 2 to 7 were measured. The measurement results are shown in Table 2 below.

(Comparative example 1)
As the metal element-containing powder of Comparative Example 1, the same metal element-containing particles as those used in Example 1 were prepared. That is, the metal element-containing powder of Comparative Example 1 consisted of only the metal element-containing particles, and did not have a cured product of the resin composition.

  [C] of Comparative Example 1 was measured in the same manner as Example 1. A toroidal of Comparative Example 1 was produced in the same manner as in Example 1. The magnetic loss and toroidal density of Comparative Example 1 were measured in the same manner as in Example 1. The measurement results are shown in Table 2 below.

(Example 8)
In preparation of the metal element containing powder | flour of Example 8, the surface treatment liquid shown by following Table 3 was used. Moreover, in preparation of the metal element containing powder of Example 8, the powder of Fe-type alloy containing Fe, Nb, Cu, Si, and B was used as metal element containing particle | grains. As a powder of an Fe-based alloy, a powder produced from a metal foil by a water atomization method was used. The particle diameter D50 of the powder of the Fe-based alloy was 25 μm. In preparation of the metal element-containing powder of Example 8, the mass of the metal element-containing particles and the surface treatment liquid contained in the mixture in the polybin was adjusted to the value (unit: g) shown in Table 3 below. In the preparation of the metal element-containing powder of Example 8, the drying temperature was 100.degree. The metal element-containing powder of Example 8 was produced in the same manner as in Example 1 except for the above matters.

  [C] of Example 8 was measured in the same manner as in Example 1. [C] of Example 8 is shown in Table 3 below.

[Preparation of compound]
In a 100 mL polycup, 14.45 g of an epoxy resin, 7.9 g of a phenol resin, 0.15 g of a curing accelerator, and 30 g of acetone (manufactured by Wako Pure Chemical Industries, Ltd.) were placed. As epoxy resin, YX-4000H manufactured by Japan Epoxy Resins Co., Ltd. was used. The epoxy equivalent of the epoxy resin was 196 g / eq. As phenolic resin, HP-850N made by Hitachi Chemical Co., Ltd. was used. The hydroxyl equivalent of the phenol resin was 103 g / eq. As a curing accelerator, C11Z-CN manufactured by Shikoku Kasei Kogyo Co., Ltd. was used. The raw material in the polycup was stirred and mixed for 10 minutes to obtain an epoxy resin solution.

  In 50 mL of poly bottles, 47.75 g of the metal element-containing powder of Example 8 and 5.25 g of the above epoxy resin solution were placed. The polybin was shaken for 10 minutes to mix the ingredients in the polybin to obtain a mixture. The mixture in the polybin was transferred to a metal vat and allowed to dry for 30 minutes. The drying method was air drying. The dried mixture was then placed in an oven preheated to 180 ° C. The mixture was dried by heating the mixture in an oven. The drying temperature was 180 ° C. The drying time was 1 hour. The compound was obtained by the above method.

[Preparation of toroidal]
The compound of Example 8 was loaded into a mold preheated to 200 ° C. The compound in the mold was pressed using a hydraulic press for 3 minutes to obtain a toroidal. The pressure applied to the compound was 300 MPa (3 ton / cm ² ). The toroidal shape had an outer diameter of 20 mm, an inner diameter of 12 mm, and a length of 2 mm.

  The magnetic loss and toroidal density of Example 8 were measured in the same manner as in Example 1. The measurement results are shown in Table 3 below.

(Comparative example 2)
As the metal element-containing powder of Comparative Example 2, the same metal element-containing particles as those used in Example 8 were prepared. That is, the metal element-containing powder of Comparative Example 2 consisted of only the metal element-containing particles, and did not have a cured product of the resin composition.

  [C] of Comparative Example 2 was measured in the same manner as in Example 1. The compound of Comparative Example 2 was produced in the same manner as in Example 8. A toroidal of Comparative Example 2 was produced in the same manner as in Example 8. The magnetic loss and toroidal density of Comparative Example 2 were measured in the same manner as in Example 1. The measurement results are shown in Table 3 below.

  The metal element-containing powder according to the present invention has high industrial value because it is suitable as a material for producing a compact having a small magnetic loss.

Claims (6)

Metal element-containing particles,
A cured product of the resin composition covering the metal element-containing particles;
Including
The resin composition contains an epoxy resin,
Metal element containing powder. The resin composition contains a phenolic resin,
The metal element-containing powder according to claim 1. The content of the cured product is 0.5% by volume or more and 2.0% by volume or less.
The metal element-containing powder according to claim 1 or 2. Used for magnetic core,
The metal element containing powder as described in any one of Claims 1-3. The metal element-containing powder according to any one of claims 1 to 4.
Molded body. Attaching a solvent in which the resin composition is dissolved to the surface of the metal element-containing particles;
Obtaining the metal element-containing particles covered with the resin composition by removing the solvent attached to the surface of the metal element-containing particles;
Curing the resin composition covering the metal element-containing particles;
Equipped with
Method for producing metal element-containing powder.