Resin molding material, method for producing resin molding material, molded article, and method for producing molded article

Abstract

To provide a resin molding material to form a magnetic material which has high saturation magnetic flux density and excellent mechanical strength such as bending strength.SOLUTION: The resin molding material comprises (A) an epoxy resin, (B) a curative, (C) a compound represented by the specified general formula (1), and (D) soft magnetic particles, and is in a granular or tablet form.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resin molding material, a method for manufacturing a resin molding material, a molded article, and a method for manufacturing a molded article.

Background Art

[0002] As components of various electrical and electronic products, coils provided with magnetic cores / exterior members (also called "reactors", "inductors", etc. depending on the application field) are being actively studied. In addition, moldable magnetic materials for producing such magnetic cores and exterior members of coils are also being actively studied.

[0003] For example, Patent Document 1 discloses a soft magnetic powder composition containing 80 to 93% by weight of a soft magnetic material and 7 to 20% by weight of a polymer material. And it is described in the document that a silane coupling agent can be used to improve the bonding property between the organic material and the inorganic material.

[0004] Patent Document 2 discloses a bonded magnet cured body in which a silicone component is present in the voids of a bonded magnet obtained by compression molding or curing a resin compound containing an epoxy resin composition and powder for magnets. And it is described in the document that a silane coupling agent can be used to enhance the adhesion between the resin composition and the surface of the magnetic powder.

[0005] Patent Document 3 discloses a compound containing a resin composition containing an epoxy resin, a phenol resin, a wax, and an imidazole-based compound, and a metal element-containing powder. And it is described in the document that a silane coupling agent can be used to enhance the adhesion between the resin composition and the metal element-containing powder and improve the flexibility and mechanical strength of a molded body formed from the compound. Patent Document 4 discloses a resin composition for sealing containing a predetermined silane coupling agent. Patent Documents 5 to 7 describe resin molding materials containing aminophenyl-based silane coupling agents, but no specific examples using such silane coupling agents are described.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Summary of the Invention

Problems to be Solved by the Invention

[0007] Here, in order to increase the saturation magnetic flux density of the magnetic material obtained from the resin molding material (composition), it is necessary to increase the filling amount of the soft magnetic powder. However, when the filling amount of the soft magnetic powder is increased, the resin molding material tends to become brittle and the mechanical strength such as the bending strength decreases. That is, there is a trade-off relationship between the increase in the saturation magnetic flux density of the magnetic material and the improvement of the mechanical strength such as the bending strength.

[0008] Patent Documents 1 and 2 do not specifically describe what silane coupling agent can be used, and there is room for improvement in the mechanical strength such as bending strength of the compositions described in these documents.

[0009] In Patent Document 3, 3-glycidoxypropyltrimethoxysilane is used in the examples, but there is still room for improvement in the mechanical strength such as bending strength.

Means for Solving the Problems

[0010] As a result of intensive studies, the inventors of the present invention have completed the invention provided below and solved the above problems. According to the present invention, (A) an epoxy resin, (B) a curing agent, (C) a compound represented by the following general formula (1), (D) soft magnetic particles, and a resin molding material in the form of tablets or granules is provided.

Chemical Formula

[0011] According to the present invention, it is possible to provide a resin molding material capable of obtaining a magnetic material having a high saturation magnetic flux density and excellent mechanical strength such as bending strength. [Brief Description of the Drawings]

[0012]

Figure 1

Figure 2

Figure 3

[0013] Hereinafter, embodiments of the present invention will be described. In addition, "~" represents "from... to..." unless otherwise specified.

[0014] The resin molding material of the present embodiment contains (A) an epoxy resin, (B) a curing agent, (C) a compound represented by the general formula (1), and (D) soft magnetic particles, and is in the form of tablets or granules. The resin molding material of the present embodiment has a high saturation magnetic flux density and can obtain a magnetic material having excellent mechanical strength such as bending strength.

[0015] [Epoxy Resin (A)] The resin molding material of this embodiment contains an epoxy resin (A). The epoxy resin (A) is not particularly limited as long as it can exhibit the effects of the present invention, and known compounds can be used.

[0016] Examples of the epoxy resin (A) include bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethyl bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol E type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, and bisphenol Z type epoxy resin; novolac type epoxy resins such as phenol novolac type epoxy resin and cresol novolac type epoxy resin; biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, aryl alkylene type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, fluorene type epoxy resin, triphenylmethane type epoxy resin, etc. Specific epoxy resins include those that are solid at 23°C among these. The resin molding material of this embodiment may contain only one type of epoxy resin or two or more types of epoxy resins. Also, epoxy resins of the same type but different molecular weights may be used in combination.

[0017] The epoxy resin (A), particularly as a specific epoxy resin, preferably contains at least one selected from the group consisting of an epoxy resin containing a triphenylmethane structure and / or an epoxy resin containing a biphenyl structure. Due to the appropriate rigidity of the structures of these epoxy resins, the heat resistance and durability of the obtained molded body can be enhanced.

[0018] From another perspective, the epoxy resin (A) preferably contains a bisphenol A type or F type epoxy resin as a specific epoxy resin. Since the resin skeleton of this epoxy resin is moderately flexible, it is easy to enhance the flow characteristics during transfer molding or lower the molding temperature during transfer molding. Furthermore, the moldability (fillability) during transfer molding and compression molding is improved.

[0019] In particular, it is preferable to use in combination (i) at least one selected from the group consisting of an epoxy resin containing a triphenylmethane structure and / or an epoxy resin containing a biphenyl structure, and (ii) a bisphenol A type or F type epoxy resin in terms of the balance of various performances.

[0020] The epoxy resin containing a triphenylmethane structure is specifically an epoxy resin containing a partial structure in which three of the four hydrogen atoms of methane (CH4) are substituted with benzene rings. The benzene ring may be unsubstituted or substituted with a substituent. Examples of the substituent include a hydroxy group and a glycidyloxy group.

[0021] Specifically, the epoxy resin containing a triphenylmethane structure contains a structural unit represented by the following general formula (a1). When two or more of these structural units are consecutive, a triphenylmethane skeleton is formed.

[0022]

Chemical formula

[0023] In the general formula (a1), R 11 when there are a plurality of them, each is independently a monovalent organic group, a halogen atom, a hydroxy group or a cyano group, R 12 when there are a plurality of them, each is independently a monovalent organic group, a halogen atom, a hydroxy group or a cyano group, i is an integer from 0 to 3, j is an integer from 0 to 4.

[0024] R 11 and R 12 Examples of the monovalent organic groups of and R include those listed as the monovalent organic groups of R and R in the general formula (BP) described below. a and R b can be exemplified by those listed as the monovalent organic groups of and R. i and j are each independently, preferably 0 to 2, more preferably 0 to 1.

[0025] In one aspect, both i and j are 0. That is, in one aspect, all of the benzene rings in the general formula (a1) do not have substituents other than the explicitly shown glycidyloxy group as the monovalent substituent.

[0026] The epoxy resin containing a biphenyl structure specifically refers to an epoxy resin containing a structure in which two benzene rings are connected by a single bond. The benzene rings here may or may not have substituents. Specifically, the epoxy resin containing a biphenyl structure has a partial structure represented by the following general formula (BP).

[0027]

Chemical formula

[0028] In the general formula (BP), R a and R b When there are a plurality of them, they are each independently a monovalent organic group, a hydroxyl group or a halogen atom, r and s are each independently 0 to 4, * represents being connected to another atomic group.

[0029] R a and R bSpecific examples of the monovalent organic group include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkaryl group, a cycloalkyl group, an alkoxy group, a heterocyclic group, a carboxyl group, and the like.

[0030] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a neopentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and the like.

[0031] Examples of the alkenyl group include an allyl group, a pentenyl group, a vinyl group, and the like. Examples of the alkynyl group include an ethynyl group and the like. Examples of the alkylidene group include a methylidene group, an ethylidene group, and the like. Examples of the aryl group include a tolyl group, a xylyl group, a phenyl group, a naphthyl group, an anthracenyl group.

[0032] Examples of the aralkyl group include a benzyl group, a phenethyl group, and the like. Examples of the alkaryl group include a tolyl group, a xylyl group, and the like. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, and the like.

[0033] Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an s-butoxy group, an isobutoxy group, a t-butoxy group, an n-pentyloxy group, a neopentyloxy group, an n-hexyloxy group, and the like. Examples of the heterocyclic group include an epoxy group, an oxetanyl group, and the like.

[0034] R a and R bThe total carbon number of each monovalent organic group is, for example, 1 to 30, preferably 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 6. r and s are each independently preferably 0 to 2, more preferably 0 to 1. In one aspect, both r and s are 0.

[0035] More specifically, the epoxy resin containing a biphenyl structure has a structural unit represented by the following general formula (BP1).

[0036]

Chemical formula

[0037] In general formula (BP1), R a and R b have the same definitions and specific aspects as in general formula (BP), The definitions and preferred ranges of r and s are the same as in general formula (BP), R c , when there are a plurality of them, are each independently a monovalent organic group, a hydroxyl group, or a halogen atom, t is an integer from 0 to 3.

[0038] R c Specific examples of the monovalent organic group of a and R b can be the same as those listed as specific examples of t is preferably 0 to 2, more preferably 0 to 1.

[0039] Specific examples of bisphenol A-type or F-type epoxy resins (epoxy resins produced by the condensation reaction of bisphenol A or bisphenol F and epichlorohydrin) include epoxy resins represented by the following general formula (EP).

[0040]

Chemical formula

[0041] In the general formula (EP), the plurality of Rs are each independently a hydrogen atom or a methyl group, preferably a methyl group, R a , R b , R c and R d are each, when there are a plurality of them, each independently a monovalent organic group, a hydroxyl group or a halogen atom, p, q, r and s are each independently 0 to 4, preferably 0 to 2, n is an integer of 0 or more, usually 0 to 10, preferably 0 to 5.

[0042] R a , R b , R c and R d Specific examples of the monovalent organic groups of a and R b are the same as those exemplified as specific examples of the monovalent organic groups of R The amount of the epoxy resin (A) in the resin molding material of the present embodiment is, for example, 0.1 to 20% by mass, preferably 0.5 to 10% by mass. The amount of the epoxy resin (A) in the resin molding material of the present embodiment is, for example, 0.5 to 60% by volume, preferably 3 to 40% by volume.

[0043] [Hardening agent (B)] The resin molding material of the present embodiment contains a hardening agent (B). The hardening agent (B) is not particularly limited as long as it can react with the epoxy groups of the epoxy resin (A) to form bonds.

[0044] Examples of the hardening agent (B) include amine compounds such as aliphatic polyamines, aromatic polyamines, aromatic diamines, dicyandiamide diamides, acid anhydrides such as alicyclic acid anhydrides and aromatic acid anhydrides, phenol compounds such as novolak type phenol resins, imidazole compounds, and the like. Specific hardening agents include those that are solid at 23°C among these.

[0045] The curing agent (B) preferably contains a phenolic curing agent (phenolic compound) as a specific curing agent. Thereby, further improvement in the durability of the finally obtained molded article can be expected. The phenolic curing agent typically has two or more hydroxy groups per molecule.

[0046] The phenolic curing agent preferably contains any skeleton selected from the group consisting of a novolac skeleton and a biphenyl skeleton. By the phenolic curing agent containing any of these skeletons, the durability of the molded article can be particularly enhanced. The "biphenyl skeleton" specifically refers to a structure in which two benzene rings are linked by a single bond, such as the general formula (BP) in the description of the aforementioned epoxy resin (A).

[0047] Specific examples of the phenolic curing agent having a biphenyl skeleton include those having a structure in which the glycidyl group in the general formula (BP1) in the description of the aforementioned epoxy resin (A) is replaced with a hydrogen atom. Specific examples of the phenolic curing agent having a novolac skeleton include those having a structural unit represented by the following general formula (N).

[0048]

Chemical formula

[0049] In the general formula (N), R 4 represents a monovalent substituent, u is an integer from 0 to 3. R 4 Specific examples of the monovalent substituent of a and R b are the same as those described as the monovalent substituents of u is preferably from 0 to 2, more preferably from 0 to 1, and still more preferably 0.

[0050] When the curing agent (B) is a polymer or an oligomer, the number average molecular weight of the curing agent (B) (value in terms of standard polystyrene by GPC measurement) is, for example, about 200 to 800. The content of the curing agent (B) in the resin molding material is, for example, 0.1 to 20% by mass, preferably 0.5 to 10% by mass. Also, the content of the curing agent (B) in the resin molding material is, for example, 0.5 to 60% by volume, preferably 3 to 40% by volume.

[0051] By appropriately adjusting the amount of the curing agent (B), the fluidity can be further improved, and the mechanical properties and magnetic properties of the resulting cured product can be improved. By appropriately adjusting the amount of the curing agent (B), the moldability can be further improved, and the mechanical properties and magnetic properties of the resulting cured product can be improved.

[0052] [Compound (C) represented by general formula (1)] The resin molding material of the present embodiment contains a compound (C) represented by the following general formula (1). In the present embodiment, by containing the compound (C), it is possible to provide a resin molding material from which a magnetic material having a high saturation magnetic flux density and excellent mechanical strength such as flexural strength can be obtained.

[0053] [Chemical formula]

[0054] In general formula (1), R 1 represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group.

[0055] Examples of alkyl groups having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a neopentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. Examples of cycloalkyl groups having 3 to 10 carbon atoms include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.

[0056] Examples of alkoxy groups having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an s-butoxy group, an isobutoxy group, a t-butoxy group, an n-pentyloxy group, a neopentyloxy group, and an n-hexyloxy group.

[0057] Examples of alkenyl groups having 1 to 10 carbon atoms include a vinyl group, a propenyl group, a 1-butenyl group, an isobutenyl group, a 1-pentenyl group, a 2-pentenyl group, a 2-methyl-1-butenyl group, a 2-cyclopentenyl group, a 1-vinylhexyl group, a styryl group, a styrylmethyl group, and a 2-styrylethyl group.

[0058] Examples of alkynyl groups having 1 to 10 carbon atoms include an ethynyl group, a propynyl group, a 1-butynyl group, a 1-pentynyl group, a 2-pentynyl group, and a 2-methyl-1-pentynyl group. Examples of aryl groups include a tolyl group, a xylyl group, a phenyl group, a naphthyl group, and an anthracenyl group. Examples of aralkyl groups include a benzyl group and a phenethyl group.

[0059] The substituted cycloalkyl group having 3 to 10 carbon atoms, substituted aryl group or substituted aralkyl group may have substituents such as a halogen atom, hydroxyl group, carboxyl group, amino group, cyano group, mercapto group, alkyl group having 1 to 5 carbon atoms, haloalkyl group having 1 to 5 carbon atoms, alkoxy group having 1 to 5 carbon atoms, haloalkoxy group having 1 to 5 carbon atoms, etc., and may have one or more selected from these.

[0060] In the present embodiment, from the viewpoint of the effects of the present invention, R 1 is preferably a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group.

[0061] R 2 represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms. As these groups, the groups exemplified for R 1 can be used. In the present embodiment, from the viewpoint of the effects of the present invention, R 2 is preferably an alkylene group having 1 to 10 carbon atoms.

[0062] A each independently represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.

[0063] Examples of the compound (C) include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane (KBM-602, manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.), 3-aminopropyltrimethoxysilane (KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.), 3-aminopropyltriethoxysilane (KBE-903, manufactured by Shin-Etsu Chemical Co., Ltd.), 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine (KBE-9103P, manufactured by Shin-Etsu Chemical Co., Ltd.), N-phenyl-3-aminopropyltrimethoxysilane (KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd. / CF-4083: manufactured by Toray Dow Corning Co., Ltd.), etc.

[0064] The resin molding material of the present embodiment can contain the compound (C) in an amount of 0.01 to 0.5% by mass, preferably 0.02 to 0.2% by mass. The resin molding material of the present embodiment can contain the compound (C) in an amount of 0.03 to 1.5% by volume, preferably 0.05 to 1.0% by mass. Thereby, a resin molding material excellent in mechanical strength such as bending strength can be provided.

[0065] [Soft magnetic particles (D)] The resin molding material of the present embodiment contains soft magnetic particles (D). Note that soft magnetism refers to ferromagnetism with a small coercive force, and generally, ferromagnetism with a coercive force of 800 A / m or less is called soft magnetism.

[0066] Examples of the constituent material of the soft magnetic particles (D) include metal-containing materials in which the iron content as a constituent element is 85% by mass or more. Such metal materials with a high iron content as a constituent element exhibit soft magnetism with relatively good magnetic properties such as magnetic permeability and magnetic flux density. Therefore, for example, when molded into a magnetic core or the like, a resin molding material that can exhibit good magnetic properties can be obtained.

[0067] Examples of the form of the above metal-containing material include, for example, a single substance, as well as alloys such as solid solutions, eutectics, and intermetallic compounds. By using particles composed of such metal materials, a resin molding material having excellent magnetic properties derived from iron, that is, magnetic properties such as high magnetic permeability and high magnetic flux density, can be obtained.

[0068] In addition, the above metal-containing material may contain elements other than iron as constituent elements. Examples of elements other than iron include B, C, N, O, Al, Si, P, S, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Cd, In, Sn, etc., and one or more of these are used in combination. In the present embodiment, it can contain one or more elements selected from Fe, Ni, Si, and Co as main elements.

[0069] Specific examples of the above metal-containing materials include, for example, pure iron, silicon steel, iron-cobalt alloy, iron-nickel alloy, iron-chromium alloy, iron-aluminum alloy, carbonyl iron, stainless steel, or composite materials containing one or more of these. From the perspective of availability, etc., silicon steel or carbonyl iron can be preferably used. The soft magnetic particles (Fe-based soft magnetic particles) may be other particles. For example, magnetic particles including Ni-based soft magnetic particles, Co-based soft magnetic particles, etc. may be used. As the soft magnetic particles (D), crystalline magnetic powder or amorphous magnetic powder can be used, or these can be mixed and used.

[0070] The resin molding material of this embodiment contains soft magnetic particles (D) in an amount of 70% by volume or more and 85% by volume or less. Thereby, a magnetic material with a high saturation magnetic flux density can be obtained.

[0071] (Curing catalyst (E)) The resin molding material of this embodiment preferably contains a curing catalyst (E). The curing catalyst (E) may sometimes be called a curing accelerator, etc. The curing catalyst (E) is not particularly limited as long as it accelerates the curing reaction of the epoxy resin (A), and known curing catalysts can be used.

[0072] Specifically, phosphorus atom-containing compounds such as organic phosphines, tetra-substituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, adducts of phosphonium compounds and silane compounds, etc.; imidazoles such as 2-methylimidazole, 2-phenylimidazole (imidazole-based curing accelerators); amidines and tertiary amines such as 1,8-diazabicyclo[5.4.0]undecene-7, benzyldimethylamine, etc., and nitrogen atom-containing compounds such as quaternary salts of amidines and amines can be exemplified. Only one kind may be used, or two or more kinds may be used.

[0073] Among these, from the viewpoint of obtaining a magnetic material with improved curability and excellent mechanical strength such as flexural strength, it is preferable to contain a phosphorus atom-containing compound, and it is more preferable to contain those having latency such as a tetra-substituted phosphonium compound, a phosphobetaine compound, an adduct of a phosphine compound and a quinone compound, an adduct of a phosphonium compound and a silane compound, etc., and a tetra-substituted phosphonium compound, an adduct of a phosphine compound and a quinone compound, and an adduct of a phosphonium compound and a silane compound are particularly preferable. By using in combination the compound (C) represented by the general formula (1) and a latent curing catalyst, a magnetic material having more excellent moldability and more excellent mechanical strength such as flexural strength can be obtained.

[0074] Examples of the organic phosphine include primary phosphines such as ethylphosphine and phenylphosphine; secondary phosphines such as dimethylphosphine and diphenylphosphine; and tertiary phosphines such as trimethylphosphine, triethylphosphine, tributylphosphine, and triphenylphosphine.

[0075] Examples of the tetra-substituted phosphonium compound include compounds represented by the following general formula (6).

[0076]

Chemical formula

[0077] In the general formula (6), P represents a phosphorus atom. R 4 、R 5 、R 6 and R 7 each independently represents an aromatic group or an alkyl group. A represents an anion of an aromatic organic acid having at least one functional group selected from a hydroxyl group, a carboxyl group, and a thiol group in the aromatic ring. AH represents an aromatic organic acid having at least one functional group selected from a hydroxyl group, a carboxyl group, and a thiol group on an aromatic ring. x and y are 1 to 3, z is 0 to 3, and x = y.

[0078] The compound represented by the general formula (6) can be obtained, for example, as follows. First, a tetra-substituted phosphonium halide, an aromatic organic acid, and a base are mixed in an organic solvent and uniformly mixed to generate an aromatic organic acid anion in the solution system. Then, when water is added, the compound represented by the general formula (6) can be precipitated. In the compound represented by the general formula (6), R bonded to the phosphorus atom 4 , R 5 , R 6 and R 7 are preferably phenyl groups, AH is a compound having a hydroxyl group on the aromatic ring, that is, phenols, and A is an anion of the phenols. Examples of the above phenols include monocyclic phenols such as phenol, cresol, resorcinol, and catechol, condensed polycyclic phenols such as naphthol, dihydroxynaphthalene, and anthraquinol, bisphenols such as bisphenol A, bisphenol F, and bisphenol S, and polycyclic phenols such as phenylphenol and biphenol.

[0079] Examples of the phosphobetaine compound include compounds represented by the following general formula (7).

[0080]

Chemical formula

[0081] In the general formula (7), P represents a phosphorus atom. R 8 is an alkyl group having 1 to 3 carbon atoms, and R 9 represents a hydroxyl group. f is 0 to 5, and g is 0 to 3.

[0082] The compound represented by the general formula (7) can be obtained, for example, as follows. First, it is obtained through a step of contacting a triaromatic-substituted phosphine, which is a tertiary phosphine, with a diazonium salt to substitute the diazonium group possessed by the triaromatic-substituted phosphine and the diazonium salt.

[0083] Examples of the adduct of the phosphine compound and the quinone compound include compounds represented by the following general formula (8).

[0084]

Chemical formula

[0085] In the general formula (8), P represents a phosphorus atom. R 10 , R 11 and R 12 represent an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and may be the same as or different from each other. R 13 , R 14 and R 15 represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and may be the same as or different from each other. R 14 and R 15 may be bonded to form a cyclic structure.

[0086] As the phosphine compound used for the adduct of the phosphine compound and the quinone compound, those having no substitution or substituents such as an alkyl group or an alkoxyl group on the aromatic ring, such as triphenylphosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, trinaphthylphosphine, and tris(benzyl)phosphine, are preferred. Examples of the substituents such as an alkyl group and an alkoxyl group include those having 1 to 6 carbon atoms. From the viewpoint of easy availability, triphenylphosphine is preferred.

[0087] In addition, examples of the quinone compound used in the adduct of the phosphine compound and the quinone compound include benzoquinone and anthraquinones. Among them, p-benzoquinone is preferable from the viewpoint of storage stability.

[0088] As a method for producing an adduct of a phosphine compound and a quinone compound, an adduct can be obtained by contacting and mixing both an organic tertiary phosphine and a benzoquinone in a solvent in which both can dissolve. As the solvent, ketones such as acetone and methyl ethyl ketone, which have low solubility in the adduct, are preferable. However, it is not limited thereto.

[0089] In the compound represented by the general formula (8), R10, R11, and R12 bonded to the phosphorus atom are phenyl groups, and R 13 , R 14 and R 15 are hydrogen atoms, that is, a compound obtained by adding 1,4-benzoquinone and triphenylphosphine is preferable in terms of reducing the storage modulus of the cured product of the sealing resin composition.

[0090] Examples of the adduct of the phosphonium compound and the silane compound include a compound represented by the following general formula (9).

[0091]

Chemical formula

[0092] In the general formula (9), P represents a phosphorus atom, and Si represents a silicon atom. R 16 , R 17 , R 18 and R 19 each represent an organic group having an aromatic ring or a heterocyclic ring, or an aliphatic group, and may be the same or different from each other. R 20 is an organic group that binds to the groups Y 2 and Y 3 . R 21 is a group Y4 and Y 5 is an organic group that binds to Y 2 and Y 3 represent a group formed by a proton-donating group releasing a proton, and the groups Y 2 and Y 3 in the same molecule bind to a silicon atom to form a chelate structure. Y 4 and Y 5 represent a group formed by a proton-donating group releasing a proton, and the groups Y 4 and Y 5 in the same molecule bind to a silicon atom to form a chelate structure. R 20 , and R 21 may be the same as or different from each other, and Y 2 Y 3 Y 4 and Y 5 may be the same as or different from each other. Z1 is an organic group having an aromatic ring or a heterocyclic ring, or an aliphatic group.

[0093] In general formula (9), R 16 R 17 R 18 and R 19 include, for example, a phenyl group, a methylphenyl group, a methoxyphenyl group, a hydroxyphenyl group, a naphthyl group, a hydroxynaphthyl group, a benzyl group, a methyl group, an ethyl group, an n-butyl group, an n-octyl group, and a cyclohexyl group, etc. Among these, aromatic groups or unsubstituted aromatic groups having substituents such as alkyl groups, alkoxy groups, and hydroxyl groups, such as a phenyl group, a methylphenyl group, a methoxyphenyl group, a hydroxyphenyl group, and a hydroxynaphthyl group, are more preferable.

[0094] In general formula (9), R 20 is an organic group that binds to Y 2 and Y 3 . Similarly, R 21 is the group Y 4 and Y 5is an organic group that binds to Y. 2 and Y 3 is a group formed by a proton-donating group releasing a proton, and the groups Y 2 and Y 3 in the same molecule bind to a silicon atom to form a chelate structure. Similarly, Y 4 and Y 5 is a group formed by a proton-donating group releasing a proton, and the groups Y 4 and Y 5 in the same molecule bind to a silicon atom to form a chelate structure. The groups R 20 and R 21 may be the same as or different from each other, and the groups Y 2 , Y 3 , Y 4 , and Y5 may be the same as or different from each other. The groups represented by -Y 2 -R 20 -Y 3 - and Y 4 -R 21 -Y 5 - in the general formula (9) are composed of groups formed by a proton donor releasing two protons. As the proton donor, an organic acid having at least two carboxyl groups or hydroxyl groups in the molecule is preferable, and further, an aromatic compound having at least two carboxyl groups or hydroxyl groups at adjacent carbons constituting an aromatic ring is preferable, and an aromatic compound having at least two hydroxyl groups at adjacent carbons constituting an aromatic ring is more preferable. Examples include catechol, pyrogallol, 1,2-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,2'-biphenol, 1,1'-bi-2-naphthol, salicylic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, chloranilic acid, tannic acid, 2-hydroxybenzyl alcohol, 1,2-cyclohexanediol, 1,2-propanediol, and glycerin, etc. Among these, catechol, 1,2-dihydroxynaphthalene, and 2,3-dihydroxynaphthalene are more preferable.

[0095] Z in the general formula (9) 1represents an organic group or an aliphatic group having an aromatic ring or a heterocyclic ring. Specific examples thereof include aliphatic hydrocarbon groups such as methyl group, ethyl group, propyl group, butyl group, hexyl group and octyl group, aromatic hydrocarbon groups such as phenyl group, benzyl group, naphthyl group and biphenyl group, glycidyloxypropyl group, mercaptopropyl group, alkyl groups having glycidyloxy group, mercapto group, amino group such as aminopropyl group, and reactive substituents such as vinyl group. Among these, methyl group, ethyl group, phenyl group, naphthyl group and biphenyl group are more preferable from the viewpoint of thermal stability.

[0096] The production method of the adduct of the phosphonium compound and the silane compound is as follows, for example. Into a flask containing methanol, a silane compound such as phenyltrimethoxysilane and a proton donor such as 2,3-dihydroxynaphthalene are added and dissolved, and then a sodium methoxide-methanol solution is dropped while stirring at room temperature. Further, a solution prepared by dissolving a tetra-substituted phosphonium halide such as tetraphenylphosphonium bromide in advance in methanol is dropped while stirring at room temperature, and crystals are precipitated. The precipitated crystals are filtered, washed with water, and dried under vacuum to obtain an adduct of the phosphonium compound and the silane compound.

[0097] When using the curing catalyst (E), its content is preferably 0.01 to 1% by mass, more preferably 0.02 to 0.8% by mass, based on the whole resin molding material. By setting such a numerical range, a sufficient curing acceleration effect can be obtained without excessively deteriorating other performances.

[0098] (Release agent) The resin molding material of this embodiment preferably contains a release agent. Thereby, the releasability after transfer molding or compression molding can be enhanced.

[0099] Examples of the release agent include natural waxes such as carnauba wax, synthetic waxes such as montanic acid ester wax and oxidized polyethylene wax, higher fatty acids such as zinc stearate and metal salts thereof, paraffin, and compounds obtained by esterifying a copolymer of an α-olefin having 5 to 60 carbon atoms and maleic anhydride with a long-chain aliphatic alcohol having 5 to 25 carbon atoms. These may be used alone or in combination of two or more. When using a release agent, only one kind may be used, or two or more kinds may be used.

[0100] The compound obtained by esterifying the copolymer of the α-olefin having 5 to 60 carbon atoms and maleic anhydride with a long-chain aliphatic alcohol having 5 to 25 carbon atoms can be obtained, for example, by the following steps. Step (a): A step of copolymerizing an α-olefin having 5 to 60 carbon atoms and maleic anhydride to obtain a copolymer Step (b): A step of subjecting the copolymer obtained in step (a) and a long-chain aliphatic alcohol having 5 to 25 carbon atoms to an esterification reaction in the presence of trifluoromethanesulfonic acid

[0101] (Step (a)) Examples of the α-olefin having 5 to 60 carbon atoms used in step (a) include linear 1-alkenes such as 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-octadecene, 1-eicosene, 1-docosene, 1-tetracosene, 1-hexacosene, 1-octacosene, 1-triacontene, 1-hentriacontene, 1-dotriacontene, 1-tritriacontene, 1-tetratriacontene, 1-pentatriacontene, 1-hexatriacontene, 1-tetracosene, 1-hentetracosene, 1-dotetracosene, 1-tritetracosene, 1-tetratetracosene, 1-pentacontene, 1-henpentacontene, 1-dopentacontene, 1-tripentacontene, 1-pentapentacontene, 1-hexacontene, 1-heptacontene, 1-octacontene, etc., and branched 1-alkenes such as 3-methyl-1-triacontene, 3,4-dimethyl-triacontene, 3-methyl-1-tetracosene, 3,4-dimethyl-tetracosene, etc. These may be used alone or in combination of two or more thereof.

[0102] The method for producing a copolymer of an α-olefin and maleic anhydride is not particularly limited, and a general copolymerization method such as reacting raw materials can be used. For the reaction, an organic solvent in which the α-olefin and maleic anhydride are soluble may be used. The organic solvent is not particularly limited, but toluene is preferable, and aromatic solvents, ether solvents, halogen solvents, etc. can also be used. The reaction temperature varies depending on the type of organic solvent used, but from the viewpoints of reactivity and productivity, it is preferably 50 to 200°C, more preferably 100 to 150°C. The reaction time is not particularly limited as long as a copolymer is obtained, but from the viewpoint of productivity, it is preferably 1 to 30 hours, more preferably 2 to 15 hours, and even more preferably 4 to 10 hours. After completion of the reaction, unreacted components, solvents, etc. can be removed under heating and reduced pressure as necessary. The conditions are a temperature of 100 to 220°C, more preferably 120 to 180°C, and a pressure of 13.3×10 3 Pa or less, more preferably 8×10 3It is preferable that the pressure be below Pa and the time be from 0.5 to 10 hours. Further, a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or benzoyl peroxide (BPO) may be added to the reaction as necessary.

[0103] (Step (b)) The copolymer obtained in step (a) is esterified using an alcohol having 5 to 25 carbon atoms in the presence of trifluoromethanesulfonic acid.

[0104] Examples of the long-chain aliphatic alcohol having 5 to 25 carbon atoms include linear or branched long-chain aliphatic saturated alcohols such as pentyl alcohol, hexyl alcohol, octyl alcohol, decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, eicosyl alcohol, behenyl alcohol, 2-methyl-decan-1-ol, 2-ethyl-decan-1-ol, 2-hexyl-octan-1-ol, etc., and linear or branched long-chain aliphatic unsaturated alcohols such as hexenol, 2-hexen-1-ol, 1-hexen-3-ol, pentenol, 2-methyl-1-pentenol, etc. These may be used alone or in combination of two or more. Among these, from the viewpoint of blocking properties during molding, linear alcohols having 10 to 25 carbon atoms are preferable, and linear aliphatic saturated alcohols having 15 to 20 carbon atoms are more preferable.

[0105] The amount of trifluoromethanesulfonic acid is preferably 100 ppm or more and 1000 ppm or less based on the total mass of the copolymer and the alcohol in order to exhibit its performance. If it is less than the above lower limit, it does not function sufficiently as an esterification catalyst, and if it exceeds the above upper limit, the resulting esterified product may be oxidized. The oxide of the esterified product tends to reduce the continuous moldability.

[0106] The molar ratio of the copolymer obtained in step (a) to the alcohol having 5 to 25 carbon atoms is not particularly limited and can be arbitrarily set. By adjusting this reaction molar ratio, it is possible to control the degree of hydrophilicity of the esterified product. For the reaction, an organic solvent in which α-olefin and maleic anhydride are soluble may be used. There is no particular limitation on the organic solvent, but toluene is preferred, and aromatic solvents, ether solvents, halogen solvents, etc. can also be used. The reaction temperature varies depending on the type of organic solvent used, but from the viewpoints of reactivity and productivity, it is preferably 50 to 200 °C, more preferably 120 to 170 °C. The reaction time is not particularly limited as long as the copolymer is obtained, but from the viewpoint of productivity, it is preferably 1 to 30 hours, more preferably 2 to 30 hours, and even more preferably 4 to 28 hours. After the reaction is completed, if necessary, unreacted components, solvents, etc. can be removed under heating and reduced pressure, etc. The conditions are that the temperature is 100 to 220 °C, more preferably 120 to 180 °C, the pressure is 13.3×10 3 Pa or less, more preferably 8×10 3 Pa or less, and the time is preferably 0.5 to 10 hours.

[0107] The reaction yield of the esterification reaction between the copolymer and the alcohol is preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably 90% or more.

[0108] The reaction mixture containing the esterified product obtained in step (b) may contain the α-olefin that was present unreacted in step (a).

[0109] The number average molecular weight of the esterified product obtained by the method of the present invention is preferably 2,000 to 10,000. If it is within the above range, the agglomeration and solidification (blocking property) of the resin molding material are more improved, the fluidity and the mold release property from the mold are more excellent, and the generation of burrs during molding is further reduced.

[0110] When using a release agent, its content is preferably 0.01 to 3% by mass, more preferably 0.05 to 2% by mass in the entire resin molding material. Thereby, the effect of improving releasability can be surely obtained.

[0111] (Other resins) The resin molding material of the present embodiment may contain other resins other than the epoxy resin (A) as long as the handleability and the like are not excessively impaired. Examples of other resins include thermosetting resins such as phenol resins, urea resins, melamine resins, unsaturated polyester resins, and polyimide resins.

[0112] In addition, polyolefins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymers, modified polyolefins, polyamides (nylons), liquid crystal polymers such as thermoplastic polyimides and aromatic polyesters, polyphenylene oxides, polyphenylene sulfides, polycarbonates, polymethyl methacrylates, polyethers, polyether ether ketones, polyetherimides, polyacetals, styrene-based, polyolefin-based, polyvinyl chloride-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, chlorinated polyethylene-based, etc. Thermoplastic resins can also be mentioned.

[0113] (Other components) The resin molding material of the present embodiment may contain components other than the above-described components. For example, it may contain one or more of a low stress agent, an adhesion aid, a colorant, an antioxidant, a corrosion inhibitor, a dye, a pigment, a flame retardant, and the like.

[0114] (Regarding volatile organic solvents) The resin molding material of the present embodiment preferably does not contain a volatile organic solvent as a component other than the above-described various components, or contains only a small amount even if it contains one. Thereby, the handleability of the resin molding material becomes even better.

[0115] Specifically, the content of the volatile organic solvent in the resin molding material of the present embodiment is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less. Particularly preferably, the resin molding material of the present embodiment substantially does not contain a volatile organic solvent.

[0116] (Form of the resin molding material) The resin molding material of the present embodiment is preferably in tablet form or granular form at 23°C, and more preferably in tablet form. When the resin molding material is in tablet form or granular form, it is easy to distribute and store the resin molding material, and it is also easy to apply to transfer molding or compression molding.

[0117] (Properties when the resin molding material is melted) The resin molding material of the present embodiment can improve the fluidity when the resin molding material is melted, and can enhance the moldability and the like. Specifically, the melt viscosity measured under the condition of a temperature of 175°C using a constant load capillary extrusion type rheometer (flow tester) is preferably 0.1 to 200 Pa·s, more preferably 0.1 to 180 Pa·s, and even more preferably 0.1 to 150 Pa·s.

[0118] As the constant load capillary extrusion type rheometer, for example, a flow tester "CFT-500D" manufactured by Shimadzu Corporation can be used. The die hole diameter can be, for example, 0.5 mm, the die length can be, for example, 1.0 mm, and the pressure (load) can be, for example, 40 kgf (392 N).

[0119] Also, the flow length measured by a spiral flow test at a temperature of 175°C can be 15 cm or more, preferably 20 cm or more, and even more preferably 25 cm or more.

[0120] The spiral flow test can be carried out by injecting a resin molding material into a mold for measuring spiral flow according to EMMI-1-66 using, for example, a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.) under the conditions of a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a curing time of 120 seconds, and measuring the flow length. The resin molding material of this embodiment can have a gelation time at 175°C of 5 seconds or more and 300 seconds or less, preferably 10 seconds or more and 200 seconds or less.

[0121] By setting the gelation time at the molding temperature of transfer molding to be equal to or higher than the above lower limit value, the moldability in a coil (a large structure) such as an in-vehicle reactor can be improved. By setting the gelation time to be equal to or lower than the above upper limit value, variations in the relative permeability can be suppressed, and the magnetic properties can be improved.

[0122] (Glass transition temperature of the cured product) The glass transition temperature of the cured product obtained by melting and molding the resin molding material of this embodiment at 175°C and then post-curing it at 175°C for 4 hours in the atmosphere is preferably 150 to 220°C, more preferably 160 to 200°C. By designing the resin molding material so that the glass transition temperature is 150°C or higher, it is easier to meet, for example, the heat resistance requirements for in-vehicle applications. By designing the resin molding material so that the glass transition temperature is 220°C or lower, molding can be performed at a relatively low temperature. This is preferable in terms of suppressing shrinkage of the molded product due to low-temperature processing.

[0123] (Manufacturing method of the resin molding material) The manufacturing method of the resin molding material of this embodiment includes the following steps. Step a: Mix soft magnetic particles (D) and a compound (C) represented by the general formula (1). Step b: Mix the mixture obtained in step a with an epoxy resin (A) and a curing agent (B).

[0124] In step a, by premixing the soft magnetic particles (D) and the compound (C), the surface of the soft magnetic particles (D) is treated with the compound (C), which is considered to be able to improve the bonding strength with the epoxy resin (A) and the curing agent (B), and to improve the mechanical properties such as bending strength. The mixing method is not particularly limited and can be carried out using a mixer. It may be mixed all at once, or the compound (C) may be gradually added to the soft magnetic particles (D).

[0125] Step a includes step a1 of preparing a solution in which the compound (C) is dissolved in a solvent and mixing the soft magnetic particles (D) with the solution containing the compound (C), and preferably includes step a2 of heat-treating the mixture obtained in the above step. Thereby, since the compound (C) can be surely brought into contact with the surface of the soft magnetic particles (D) and surface-treated, it is considered that the bonding strength with the epoxy resin (A) and the curing agent (B) can be further improved, and the mechanical properties such as bending strength can be further improved.

[0126] Examples of the solvent used in step a1 include water, methanol, ethanol, isopropyl alcohol, etc. The solution can contain about 20% by weight of the compound (C). The heat treatment in step a2 can be carried out at about 80°C for about 1 hour. In step b, the mixture obtained in step a, the epoxy resin (A), the curing agent (B), and, if necessary, a curing catalyst (E), a release agent, other resins or other components are mixed. The mixing method is not particularly limited and can be carried out using a mixer. It may be mixed all at once, or gradually added. As described above, a resin composition (resin molding material) can be prepared by mixing the components (A) to (D), etc.

[0127] Industrially, (1) the obtained resin composition is kneaded using a roll at around 120°C for 5 minutes or more, preferably about 10 minutes to obtain a kneaded product, (2) the obtained kneaded product is cooled, and (3) then, it is pulverized to produce a resin molding material. Thus, a powdery resin molding material can be obtained.

[0128] The powdery resin molding material may be tableted into tablets. Thereby, a resin molding material particularly suitable for use in a transfer molding method or a compression molding method can be obtained.

[0129] <Molded product> The molded product of the present embodiment can be obtained by curing the above-described resin molding material. Since the molded product of the present embodiment is composed of a composite material having a high saturation magnetic flux density as described above, a high saturation magnetic flux density can be realized, which can be 1.0 T or more, preferably 1.2 T or more, more preferably 1.3 T or more.

[0130] In addition, the molded product of the present embodiment obtained from a resin molding material containing the compound represented by the general formula (1) can improve the flexural strength. Specifically, the flexural strength at room temperature of 25°C measured in accordance with JIS K 6911 can be 65 MPa or more. The upper limit value is not particularly limited but can be 300 MPa or less. The preferable range of the flexural strength at room temperature of 25°C varies depending on various physical properties such as the type and particle diameter of the soft magnetic particles (D) contained in a large amount in the molded product.

[0131] The molded product of the present embodiment can have a flexural strength at 250°C measured in accordance with JIS K 6911 of 3.5 MPa or more. The upper limit value is not particularly limited but can be 20 MPa or less. The preferable range of the flexural strength at room temperature of 250°C varies depending on various physical properties such as the type and particle diameter of the soft magnetic particles (D) contained in a large amount in the molded product. Since it has excellent flexural strength when hot, it also has excellent mechanical properties even when the molded product is used in a high-temperature environment such as an automobile engine.

[0132] The manufacturing method of the molded product is not particularly limited, and examples thereof include a transfer molding method or a compression molding method.

[0133] (Transfer molding method) The manufacturing method of the molded product by the transfer molding method includes a step of injecting the melt of the above resin molding material into a mold using a transfer molding apparatus, and a step of curing the melt. According to the resin molding material of the present embodiment, it is possible to achieve both high density of the saturation magnetic flux density of the magnetic material and mechanical properties, which are in a trade-off relationship.

[0134] Regarding transfer molding, it can be carried out by appropriately using a known transfer molding apparatus. Specifically, first, the preheated resin molding material is put into a heating chamber (also called a transfer chamber) and melted to obtain a melt. Then, the melt is injected into the mold with a plunger and held as it is to cure the melt. Thereby, a desired molded product can be obtained. Transfer molding is preferable in terms of controllability of the dimensions of the molded product and improvement of the degree of freedom of shape.

[0135] Various conditions in transfer molding can be arbitrarily set. For example, the preheating temperature is 60 to 100 °C, the heating temperature during melting is 100 to 250 °C, the mold temperature is 100 to 200 °C, and the pressure when injecting the melt of the resin molding material into the mold can be appropriately adjusted between 1 and 20 MPa. By not raising the mold temperature too high, shrinkage of the molded product can be suppressed.

[0136] (Compression molding method) The manufacturing method of the molded product by the compression molding method (compression molding method) includes a step of compression molding the resin molding material.

[0137] Regarding compression molding, it can be carried out by appropriately using a known compression molding apparatus. Specifically, the resin molding material is placed in the recess of a fixed mold having a concave shape that opens upward. The resin molding material can be preheated. Thereby, the molded product can be uniformly cured, and the molding pressure can be reduced.

[0138] Next, from above, a convex mold is moved to the concave fixed mold, and the resin molding material is compressed in the cavity formed by the convex portion and the concave portion. First, the resin molding material is softened and fluidized sufficiently at a low pressure, and then the mold is closed and pressurized again to be cured for a predetermined time.

[0139] Various conditions in compression molding can be arbitrarily set. For example, the preheating temperature is 60 to 100°C, the heating temperature during melting is 100 to 250°C, the mold temperature is 100 to 200°C, the pressure when the resin molding material is compressed by the mold is 1 to 20 MPa, and the curing time can be appropriately adjusted between 60 and 300 seconds. By not raising the mold temperature too high, shrinkage of the molded product can be suppressed.

[0140] Since the resin molding material of this embodiment has high magnetic permeability and high saturation magnetic flux density, and furthermore, a magnetic material excellent in mechanical strength such as bending strength can be obtained, a film or the like obtained by curing the resin molding material can be used, for example, for a thin film inductor, a transmission unit or a reception unit for wireless power feeding, etc. Here, a thin film inductor will be taken as an example and described. Specifically, as shown in FIG. 1, the thin film inductor 10 includes a soft magnetic thin film 12(38) made of a resin molding material and an MID (Molded Interconnect Device) circuit 14 on its upper surface. The manufacturing method of the thin film inductor 10 will be described according to the first embodiment and the second embodiment.

[0141] (First Embodiment) The manufacturing method of the thin film inductor 10 of this embodiment will be described with reference to FIG. 2. First, the soft magnetic thin film 12 is formed from the resin molding material of the present embodiment by the above-described transfer molding or compression molding (Fig. 2(a)). The film thickness of the soft magnetic thin film 12 is about 200 μm. The resin molding material of the present embodiment may contain a non-conductive metal compound that forms metal nuclei upon irradiation with active energy rays. Such a compound acts as an LDS (LASER DIRECT STRUCTURING) additive. The non-conductive metal compound is not limited as long as it can form metal nuclei upon irradiation with active energy rays. Although the detailed mechanism is not clear, when such a non-conductive metal compound is irradiated with active energy rays such as a YAG laser having an absorbable wavelength region, the metal nuclei are activated (for example, reduced), and it is considered that metal nuclei capable of metal plating are generated. Then, when the surface of the cured product of the thermosetting resin composition in which the non-conductive metal compound is dispersed is irradiated with active energy rays, a seed region having metal nuclei capable of metal plating is formed on the irradiated surface. By using the obtained seed region, it becomes possible to form a plating pattern such as a circuit on the surface of the cured product of the thermosetting resin composition.

[0142] The non-conductive metal compound includes, for example, one or more selected from the group consisting of (i) spinel-type metal oxides, (ii) metal oxides selected from Groups 3 to 12 of the periodic table and having two or more adjacent transition metal elements in the group, and (iii) tin-containing oxides.

[0143] Then, an insulating layer 13 is formed on the upper surface of the soft magnetic thin film 12 (Fig. 2(b)). The film thickness of the insulating layer 13 is about 200 μm. The insulating layer 13 can be formed from a conventionally known material and is formed by a spray method, a coating method, or various molding methods.

[0144] An active energy ray is irradiated onto a portion (MID circuit pattern) where the MID circuit 14 is to be formed on the upper surface of the insulating layer 13 to etch the insulating layer 13, thereby forming an opening 15 in which the soft magnetic thin film 12 is exposed (FIG. 2(c)). Further, the active energy ray is irradiated onto the soft magnetic thin film 12 exposed in the opening 15 to activate the surface of the soft magnetic thin film 12 to a state where metal can be deposited. Specifically, as described above, it is considered that the soft magnetic material contained in the soft magnetic thin film 12 is exposed on the surface by irradiation with the active energy ray, enabling electroless plating on the surface of the soft magnetic thin film 12. Further, the surface of the soft magnetic thin film 12 is roughened by irradiation with the active energy ray, improving the adhesion to the copper layer 16 described later. Also, after forming the opening 15, an insulating layer can be formed over the entire upper surface of the soft magnetic thin film 12, and the insulating layer can be etched by irradiating an active energy ray to form an insulating layer on the sidewall of the opening 15.

[0145] Next, a plating process is performed to deposit copper on the activated surface of the soft magnetic thin film 12 in the opening 15 to form a copper layer 16 in the opening 15 (FIG. 2(d)). Through the above steps, a thin film inductor 10 including the MID circuit 14 formed of the copper layer 16 on the soft magnetic thin film 12 can be obtained. Note that the thin film inductor 10 can also have the structure shown in FIG. 2(d1).

[0146] (Second Embodiment) A method for manufacturing the thin film inductor 10 of the present embodiment will be described with reference to FIG. 3. First, an LDS thermosetting resin composition is applied and dried by a die coater to form an MID film 32 (FIG. 3(a)). The film thickness of the MID film 32 is about 200 μm. The LDS thermosetting resin composition contains a thermosetting resin, an inorganic filler, and a non-conductive metal compound that forms metal nuclei by irradiation with the above-described active energy ray. As the thermosetting resin and the inorganic filler, known materials can be used.

[0147] On the upper surface of the MID film 32, the MID film 32 is irradiated with active energy rays at a location (MID circuit pattern) where the MID circuit 14 is to be formed, thereby etching the MID film 32 to form an opening 34 (FIG. 3(b)). At this time, the surface of the MID film 32 within the opening 34 is activated to a state where metal can be deposited by the irradiation of the active energy rays. Specifically, as described above, it is considered that the metal nuclei of the non-conductive metal compound contained in the MID film 32 are activated, and metal nuclei capable of metal plating are generated on the surface of the soft magnetic thin film 12. Further, the surface of the MID film 32 is roughened by the irradiation of the active energy rays, and the adhesion with the copper layer 36 described later is improved.

[0148] Then, plating treatment is performed to deposit copper on the activated surface of the MID film 32 within the opening 34, thereby forming a copper layer 36 within the opening 34 of the MID film 32 (FIG. 3(c)). Note that an insulating layer can also be formed on the surface of the copper layer 36 after this step. Next, by the above-described transfer molding or compression molding, a soft magnetic layer (thin film) 38 made of the resin molding material of the present embodiment is formed on the MID film 32 and the copper layer 36 to seal them (FIG. 3(d)).

[0149] Through the above steps, a thin film inductor 10 including the MID circuit 14 formed of the copper layer 36 can be obtained between the MID film 32 and the soft magnetic layer (thin film) 38. Note that the thin film inductor 10 can also have the structure shown in FIG. 3(d1).

[0150] Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than the above can be adopted as long as the effects of the present invention are not impaired.

Example

[0151] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

[0152] <Examples 1 to 4, Comparative Examples 1 to 2> First, each component described in Table-1 was prepared at the described ratio. First, while mixing the soft magnetic particles, a 20 wt% solution (water and methanol) of the compound represented by the general formula (1) was added thereto. After the addition, heat treatment was performed at 80 °C for 1 hour. Further, other components were added thereto and uniformly mixed to obtain a mixture. Next, the obtained mixture was kneaded under the conditions of 120 °C for 10 minutes. After the kneading was completed, the obtained kneaded product was cooled to room temperature to form a solid shape, and then pulverized and tabletted. Thus, a tablet-shaped resin molding material was obtained. The raw material components described in Table-1 are shown below. The evaluation results of the resin molding material and the molded product in Table-1 are shown. The content rate (volume %) of the soft magnetic particles described in Table-1 is the content rate (i.e., filling rate) when the resin molding material containing the soft magnetic particles is 100 volume %.

[0153] (Epoxy resin) Epoxy resin 1: jER1032H60: An epoxy resin containing a triphenylmethane structure, manufactured by Mitsubishi Chemical Corporation, solid at 23 °C, containing the structural unit represented by the general formula (a1) above Epoxy resin 2: YL-6810: A bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation, solid at 23 °C, containing the structure represented by the general formula (EP) above Epoxy resin 3: NC3000L: A biphenyl aralkyl type epoxy resin, manufactured by Nippon Kayaku Co., Ltd., solid at 23 °C, containing the structural unit represented by the general formula (BP1) above

[0154] (Hardening agent) Hardening agent 1: PR-HF-3: A novolak type phenol resin, manufactured by Sumitomo Bakelite Co., Ltd., solid at 23 °C Hardening agent 2: MEH-7851SS: A phenol aralkyl resin containing a biphenylene skeleton, manufactured by Meiwafosis Co., Ltd., solid at 23 °C

[0155] (Release agent (wax)) Release agent 1: WE-4: An ester wax, manufactured by Clariant Chemicals Ltd. Release agent 2: TOWAX-132: A carnauba wax, manufactured by Toagosei Co., Ltd. Release agent 3: A release agent obtained by the following synthesis method 100.0 g of a copolymer of 1-alkene having 28 to 60 carbon atoms and maleic anhydride (Daiyakarna R30, manufactured by Mitsubishi Chemical Corporation) and 47.0 g of stearyl alcohol were charged into a 300 ml four-neck separable flask, dissolved at 70 °C, and then 0.5 g of a 10 wt% aqueous solution of trifluoromethanesulfonic acid was added. The resulting reaction mixture was stirred at 150 °C for 5 hours. Thereafter, the liquid temperature was cooled to 120 °C, and under a reduced pressure of 30 Torr, vacuum distillation was performed for 2 hours to remove free trifluoromethanesulfonic acid and water, and 144 g of release agent 1, which is an esterified product, was obtained.

[0156] (Curing catalyst) Catalyst 1: Tetraphenylphosphonium·4,4'-sulfonyldiphenolate (a latent catalyst represented by the general formula (6) above) Catalyst 2: 2PZ-PW: 2-Phenylimidazole manufactured by Shikoku Kasei Co., Ltd. Catalyst 3: Tetraphenylphosphonium·bis(naphthalene-2,3-dioxy)phenylsilicate (a latent catalyst represented by the general formula (9) above)

[0157] (Compound represented by the general formula (1)) CF-4083: N-Phenyl-3-aminopropyltrimethoxysilane manufactured by Toray Dow Corning Co., Ltd.

[0158] (Adhesion promoter) CDA-1M: A benzotriazole-based compound represented by the following formula (1a) manufactured by ADEKA

[0159] [Chemical formula]

[0160] (Soft magnetic particles) Iron-based particle 1: Crystalline magnetic powder (manufactured by Daido Steel Co., Ltd., DAPMS7-200, median diameter D 50 : 52 μm, Fe 93 mass%) Iron-based particle 2: Amorphous magnetic powder (manufactured by Seiko Epson Corporation, KUAMET6B2 053C03, median diameter D 50 : 23 μm, Fe 87 mass%) Iron-based particle 3: (manufactured by Seiko Epson Corporation, Fe-3.5Si-4.5Cr, median diameter D 50 : 10 μm, Fe 92 mass%) Iron-based particle 4: (manufactured by BASF, CIS-HQ, median diameter D 50 : 1.8 μm, Fe 97 mass%) Iron-based particle 5: Amorphous magnetic powder (manufactured by Seiko Epson Corporation, AW2-08 PF3FG, median diameter D 50 : 3.4 μm)

[0161] (Silica) Spherical silica (fused silica, median diameter D 50 : 0.5 μm)

[0162] <Evaluation> (Flowability: Spiral flow test) The spiral flow test was conducted using the resin compositions of the examples and comparative examples. The test was carried out using a low-pressure transfer molding machine ("KTS-15" manufactured by Kotaki Seiki Co., Ltd.) to inject the resin molding material into a mold for spiral flow measurement conforming to EMMI-1-66 under the conditions of a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a curing time of 120 seconds, and measuring the flow length. The larger the numerical value, the better the flowability.

[0163] (Evaluation of mechanical strength (flexural strength)) The resin molding material was injection molded into a mold using a low-pressure transfer molding machine ("KTS-30" manufactured by Kotaki Seiki Co., Ltd.) under the conditions of a mold temperature of 175°C, an injection pressure of 9.8 MPa, and a curing time of 120 seconds. As a result, a molded product with a width of 10 mm, a thickness of 4 mm, and a length of 80 mm was obtained. Then, the obtained molded product was post-cured under the conditions of 175°C for 4 hours. Thereby, a test piece for evaluating the mechanical strength was produced. And the flexural strength (MPa) of the test piece at 250°C or 25°C was measured in accordance with JIS K 6911. Similar effects were also obtained for the test pieces obtained by compression molding.

[0164]

Table 1

[0165] From the results in Table-1, it was confirmed that the resin molding materials of the examples to which the compound (C) represented by the general formula (1) was added had a high saturation magnetic flux density, and furthermore, a magnetic material excellent in flexural strength was obtained.

Explanation of symbols

[0166] 10 Thin film inductor 12, 38 Soft magnetic thin film 13 Insulating layer 14 MID circuit 15, 34 Opening 16, 36 Copper layer 32 MID film

Claims

1. (A) an epoxy resin; (B) a curing agent; (C) a compound represented by the following general formula (1); (D) soft magnetic particles (excluding core-shell type particles including a core component formed of a magnetic material component and a shell component formed of an oxide or nitride of the magnetic material component); comprising the soft magnetic particles (D) are a metal-containing material having an iron content of 85% by mass or more as a constituent element, the content of the soft magnetic particles (D) is 70% by volume or more and 85% by volume or less, a resin molding material in the form of tablets or granules. 【Chemical 1】 (In general formula (1), R １ is a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group.) A each independently represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.)

2. (A) an epoxy resin; (B) a curing agent; (C) a compound represented by the following general formula (1); (D) soft magnetic particles (excluding core-shell type particles including a core component formed of a magnetic material component and a shell component formed of an oxide or nitride of the magnetic material component); comprising the curing agent (B) includes a phenolic curing agent, the soft magnetic particles (D) are a metal-containing material having an iron content of 85% by mass or more as a constituent element, the content of the soft magnetic particles (D) is 70% by volume or more and 85% by volume or less, a resin molding material in the form of tablets or granules. [Chemical Formula 2] (In the general formula (1), R １ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R ２ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms. A each independently represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.)

3. (A) an epoxy resin; (B) a curing agent; (C) a compound represented by the following general formula (1); (D) soft magnetic particles (excluding core-shell type particles including a core component formed of a magnetic material component and a shell component formed of an oxide or nitride of the magnetic material component); (E) a curing catalyst; comprising the soft magnetic particles (D) are a metal-containing material having an iron content of 85% by mass or more as a constituent element, the content of the soft magnetic particles (D) is 70% by volume or more and 85% by volume or less, the curing catalyst (E) is at least one selected from a tetra-substituted phosphonium compound, a phosphobetaine compound, an adduct of a phosphine compound and a quinone compound, and an adduct of a phosphonium compound and a silane compound, a resin molding material in the form of tablets or granules. 【Chemical Formula 3】 (In general formula (1), R １ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R ２ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms. A, independently of each other, represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.

4. The resin molding material according to claim 3, wherein the curing agent (B) contains a phenolic curing agent.

5. In general formula (1), R １ is a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group, and the resin molding material according to any one of claims 2 to 4.

6. The resin molding material according to any one of claims 1 to 5, wherein the soft magnetic particles (D) contain one or more elements selected from Fe, Ni, Si, and Co.

7. The resin molding material according to any one of claims 1 to 6, wherein the flow length measured by a spiral flow test at a temperature of 175 ° C is 15 cm or more.

8. The resin molding material according to any one of claims 1 to 7, wherein the melt viscosity measured under the condition of a temperature of 175 ° C using a constant load capillary extrusion type rheometer is 0.1 to 200 Pa·s.

9. Step a of mixing the soft magnetic particles (D) and the compound (C) represented by the following general formula (1); Step b of mixing the mixture obtained in step a, the epoxy resin (A), and the curing agent (B); A method for producing a resin molding material, comprising: The resin molding material contains the soft magnetic particles (D) in an amount of 70% by volume or more and 85% by volume or less. A method for producing a resin molding material. 【Chemical Formula 4】 (In general formula (1), R １ is a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group.) A, independently of each other, represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.

10. Step a of mixing the soft magnetic particles (D) and the compound (C) represented by the following general formula (1); Step b of mixing the mixture obtained in step a, the epoxy resin (A), and the curing agent (B); A method for producing a resin molding material, comprising: The curing agent (B) contains a phenolic curing agent, The resin molding material contains the soft magnetic particles (D) in an amount of 70% by volume or more and 85% by volume or less. A method for producing a resin molding material. [Chemical Formula 5] (In the general formula (1), R １ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R ２ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms. A, independently of each other, represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.

11. Step a of mixing the soft magnetic particles (D) and the compound (C) represented by the following general formula (1); Step b of mixing the mixture obtained in step a, the epoxy resin (A), the curing agent (B), and the curing catalyst (E); A method for producing a resin molding material, comprising: The resin molding material contains the soft magnetic particles (D) in an amount of 70% by volume or more and 85% by volume or less. A method for producing a resin molding material. 【Chemical Formula 6】 (In general formula (1), R １ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R ２ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms.) A each independently represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.)

12. In the general formula (1), R １ is a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group, and is a method for producing a resin molding material according to claim 10 or 11.

13. The step a is a step of mixing the soft magnetic particles (D) and the solution containing the compound (C); a step of heat-treating the mixture obtained in the above step; A method for producing a resin molding material according to any one of claims 9 to 12, comprising:

14. A molded article obtained by curing the resin molding material according to any one of claims 1 to 8.

15. A step of injecting a melt of the resin molding material according to any one of claims 1 to 8 into a mold using a transfer molding apparatus; a step of curing the melt; A method for producing a molded article, comprising:

16. A method for producing a molded article, comprising: a step of injecting a melt of a resin molding material into a mold using a transfer molding apparatus; a step of curing the melt; wherein the resin molding material comprises (A) an epoxy resin, (B) a curing agent, (C) a compound represented by the following general formula (1), (D) soft magnetic particles (excluding core-shell type particles containing a core component formed of a magnetic component and a shell component formed of an oxide or nitride of the magnetic component), and the soft magnetic particles (D) are a metal-containing material having an iron content of 85% by mass or more as a constituent element, the content of the soft magnetic particles (D) is 70% by volume or more and 85% by volume or less, and the molded article is in tablet form or granular form. [Chemical Formula 7] (In general formula (1), R １ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R ２ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms. A each independently represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and at least one A is an alkoxy group having 1 to 3 carbon atoms.)

17. A method for producing a molded article, comprising a step of compression molding the resin molding material according to any one of claims 1 to 8.

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