JP2021130811A - Resin molding material, molding, and method for producing molding - Google Patents

Abstract

To provide a resin molding material that achieves improvement in aggregation solidification (blocking properties) and has excellent flowability and releasability from a die, and also has reduced occurrence of burrs during molding.SOLUTION: A resin molding material has (A) a thermosetting resin, (B) a curing agent, (C) a compound obtained by esterification of a copolymer of a C5-60 α-olefin and a maleic anhydride with a C5-25 long-chain aliphatic alcohol, and (D) soft magnetic particles.SELECTED DRAWING: None

Description

The present invention relates to a resin molding material, a molded product, and a method for producing the molded product.

As a component of various electric and electronic products, a coil having a magnetic core / exterior member (also called a "reactor" or "inductor" depending on the application field) is being actively studied. Further, a moldable magnetic material for producing a magnetic core or an exterior member of such a coil is also being actively studied.

Patent Document 1 discloses a compound containing an epoxy resin, a phenol resin, a wax containing a montanic acid ester, an imidazole compound, and a metal-containing powder. Document 1 describes that the compound is excellent in fluidity and releasability from a mold, can reduce molding burrs, and can increase the mechanical strength of a molded product. ..
Patent Document 2 discloses an ester compound having a predetermined structure.

International Publication No. 2019/1068113 International Publication No. 2011/002905

In the technique of Patent Document 1, since the resin molding material may coagulate and solidify into a lump (blocking property) at the time of molding, the fluidity of the resin molding material may decrease or the resin molding material may be cured. Improvements have been made in that the composition of the molded product (magnetic material) becomes non-uniform, and desired characteristics such as mold releasability from the mold, magnetic properties such as magnetic permeability, and mechanical strength decrease cannot be obtained. There was room for improvement, and there was still room for improvement in reducing molding burrs. Patent Document 2 does not have an example in which the ester compound is used as a magnetic material.

By using a predetermined ester compound, the present inventors suppress coagulation and solidification (blocking property) of the resin molding material, and also have excellent fluidity and mold releasability during molding. The present invention has been completed by finding that the generation of burrs is reduced.

According to the present invention
(A) Thermosetting resin and
(B) Hardener and
(C) A compound obtained by esterifying a copolymer of an α-olefin having 5 to 60 carbon atoms and maleic anhydride with a long-chain fatty alcohol having 5 to 25 carbon atoms.
(D) Soft magnetic particles and
Resin molding materials are provided, including.
According to the present invention, a molded product obtained by curing the resin molding material is provided.
According to the present invention, a step of injecting a melt of the resin molding material into a mold using a transfer molding apparatus, and
The process of curing and molding the melt and
The process of releasing the molded product from the mold and
A method for producing an article is provided, including.
According to the present invention, a step of compression molding the resin molding material in a mold and
The process of releasing the molded product from the mold and
A method for producing an article is provided, including.

According to the resin molding material of the present invention, coagulation and solidification (blocking property) is suppressed, fluidity and mold release property from the mold are excellent, and the generation of burrs during molding can be reduced. ..

It is a photograph of the resin molding material (with a lumpy solidified product) after the test in Comparative Example 2.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, "~" represents "greater than or equal to" to "less than or equal to" unless otherwise specified.

The resin molding material of the present embodiment is composed of (A) a thermosetting resin, (B) a curing agent, (C) a copolymer of α-olefin having 5 to 60 carbon atoms and maleic anhydride, and having a carbon number of carbon atoms. It contains a compound esterified with 5 to 25 long-chain aliphatic alcohols and (D) soft magnetic particles.

According to the resin molding material of the present embodiment, coagulation and solidification during use or storage is suppressed, fluidity and releasability from the mold are excellent, and the occurrence of burrs during molding is reduced. be able to. Further, according to the resin molding material of the present embodiment, it is possible to obtain a molded product having excellent magnetic properties such as magnetic permeability and mechanical strength.

[Thermosetting resin (A)]
Examples of the thermosetting resin (A) include epoxy resin, phenol resin, urea resin, melamine resin, unsaturated polyester resin, polyimide resin, and the like, and at least one of them can be included. In the present embodiment, the thermosetting resin (A) preferably contains an epoxy resin.

(Epoxy resin)
The epoxy resin is not particularly limited, and for example, 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 type epoxy resin such as bisphenol P type epoxy resin and bisphenol Z type epoxy resin; Novolak type epoxy resin such as phenol novolac type epoxy resin and cresol novolac type epoxy resin; Biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, arylalkylene type Epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, adamantan type epoxy resin, fluorene type epoxy resin, triphenylmethane type epoxy resin, etc. Can be done. Examples of the epoxy resin include those in the form of a solid at 23 ° C.

The resin molding material of the present embodiment may contain only one type of epoxy resin, or may contain two or more types of epoxy resin. Further, even if the epoxy resins of the same type are used, those having different molecular weights may be used in combination.

The epoxy resin preferably comprises 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 structure of these epoxy resins, the heat resistance and durability of the obtained molded product can be enhanced.

As another aspect, the epoxy resin preferably contains a bisphenol A type or F type epoxy resin. Since the resin skeleton of this epoxy resin is moderately flexible, it is possible to easily improve the flow characteristics during transfer molding and to lower the molding temperature during transfer molding. Further, the moldability (fillability) at the time of transfer molding and compression molding is improved.

In particular, at least one selected from the group consisting of (i) an epoxy resin containing a triphenylmethane structure and / or an epoxy resin containing a biphenyl structure can be used in combination with (ii) a bisphenol A type or F type epoxy resin. It is preferable in terms of the balance of various performances.

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 (CH 4) are substituted with a benzene ring.} The benzene ring may be unsubstituted or substituted with a substituent. Examples of the substituent include a hydroxy group and a glycidyloxy group.

Specifically, the epoxy resin containing a triphenylmethane structure contains a structural unit represented by the following general formula (a1). A triphenylmethane skeleton is formed by connecting two or more of these structural units.

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

Examples of monovalent organic groups of R ¹¹ and R ¹² include those listed as monovalent organic groups of ^Ra and R ^b in the general formula (BP) described later.
i and j are independently, preferably 0 to 2, and more preferably 0 to 1.

In one aspect, both i and j are 0. That is, as one aspect, all of the benzene rings in the general formula (a1) have no substituent other than the specified glycidyloxy group as the monovalent substituent.

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

In the general formula (BP)
^Ra and R ^b are monovalent organic groups, hydroxyl groups or halogen atoms, respectively, if there are a plurality of them.
r and s are independently 0-4, respectively.
* Indicates that it is connected to another atomic group.

Specific examples of the monovalent organic groups of R ^a and R ^b include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkalil group, a cycloalkyl group, an alkoxy group, a heterocyclic group and a carboxyl group. The group can be mentioned.

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 and a heptyl group. Examples thereof include an octyl group, a nonyl group and a decyl group.

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.
Examples of the alkylidene group include a methylidene group and an ethylidene group.
Examples of the aryl group include a tolyl group, a xsilyl group, a phenyl group, a naphthyl group, and an anthrasenyl group.
Examples of the aralkyl group include a benzyl group and a phenethyl group.
Examples of the alkaline group include a tolyl group and a xylyl group.
Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group and the like.

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 and a neopentyloxy group. , N-hexyloxy group and the like.
Examples of the heterocyclic group include an epoxy group and an oxetanyl group.

^{The total carbon number of the monovalent organic groups of Ra} and R ^b is, for example, 1 to 30, preferably 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 6, respectively.
r and s are independently, preferably 0 to 2, and more preferably 0 to 1. In one aspect, both r and s are 0.

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

In the general formula (BP1)
^{The definitions and specific embodiments of Ra} and R ^b are the same as those of the general formula (BP).
The definitions and preferred ranges of r and s are similar to the general formula (BP).
R ^c is a monovalent organic group, a hydroxyl group or a halogen atom independently of each other when there are a plurality of them.
t is an integer from 0 to 3.

Specific examples of the monovalent organic group of R ^c include those similar to those given as specific examples of ^Ra and R ^b.
t is preferably 0 to 2, more preferably 0 to 1.

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

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

Specific examples of the monovalent organic groups of R ^a , R ^b , R ^c and R ^d are the same as those given as specific examples of the monovalent organic groups of ^Ra and R ^{b in the general formula (BP).} I can mention things.

The amount of the epoxy resin 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 in the resin molding material of the present embodiment is, for example, 0.5 to 60% by volume, preferably 3 to 40% by volume.

(Phenol resin)

The phenol resin is not particularly limited, and examples thereof include novolak-type phenol resins such as phenol novolac resin, cresol novolak resin, and bisphenol A novolak resin, and resol-type phenol resins. One of these may be used alone, or two or more may be used in combination.
Among the phenol resins, a phenol novolac resin is preferable.

(Urea resin)
The urea resin is not particularly limited, and examples thereof include a resin obtained by condensation of urea and formaldehyde.

(Melamine resin)
The melamine resin is not particularly limited, and for example, a melamine resin obtained by reacting melamine and formaldehyde under neutral or weak alkali can be used.
Further, as the melamine resin, a commercially available melamine resin such as a melamine resin manufactured by Sumitomo Chemical Co., Ltd. can also be used.

(Unsaturated polyester resin)
The unsaturated polyester resin is not particularly limited, and includes, for example, the most common orthotype using phthalic anhydride as a raw material, an isotype using isophthalic acid, and a paratype using terephthalic acid. , These prepolymers are also included. One of these can be used alone or two or more can be used in combination.

(Polyimide resin)
The polyimide resin is not particularly limited, but is synthesized, for example, by copolymerizing diamine, dianhydride and anhydride to synthesize a polyamic acid which is a precursor of polyimide, and then imidizing the polyamic acid. NS.

[Curing agent (B)]
The resin molding material of the present embodiment contains a curing agent (B).

The curing agent (B) is not particularly limited as long as it can react with the epoxy group of the epoxy resin to form a bond. For example, amine compounds such as aliphatic polyamines, aromatic polyamines, aromatic diamines and disiamine diamides, acid anhydrides such as alicyclic acid anhydrides and aromatic acid anhydrides, phenols such as novolak type phenolic resins. Examples thereof include compounds and imidazole compounds. Examples of the specific curing agent include those solid at 23 ° C.

The curing agent (B) preferably contains a phenolic curing agent (phenol compound) as a specific curing agent. As a result, it can be expected that the durability of the finally obtained molded product will be further improved. Phenolic curing agents typically have two or more hydroxy groups per molecule.

The phenolic curing agent preferably comprises any skeleton selected from the group consisting of a novolak skeleton and a biphenyl skeleton. When the phenolic curing agent contains any of these skeletons, the durability of the molded product can be particularly enhanced.
Specifically, the "biphenyl skeleton" is a structure in which two benzene rings are connected by a single bond as in the general formula (BP) in the above-mentioned explanation of the epoxy resin.

Specific examples of the phenolic curing agent having a biphenyl skeleton include those having a structure in which the glycidyl group is replaced with a hydrogen atom in the general formula (BP1) in the above-mentioned description of the epoxy resin.
Specific examples of the phenolic curing agent having a novolak skeleton include those having a structural unit represented by the following general formula (N).

In the general formula (N)
R ⁴ represents a monovalent substituent and represents
u is an integer from 0 to 3.
Specific examples of the monovalent substituent of R ⁴ include the same as those described as the monovalent substituent of ^Ra and R ^{b in the general formula (BP).}
u is preferably 0 to 2, more preferably 0 to 1, and even more preferably 0.

When the curing agent (B) is a polymer or an oligomer, the number average molecular weight (standard polystyrene conversion value measured by GPC) of the curing agent (B) is, for example, about 200 to 800.
The content of the curing agent in the resin molding material is, for example, 0.1 to 20% by mass, preferably 0.5 to 10% by mass.

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.
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 obtained cured product can be improved.

[Compound (C)]
The resin molding material of the present embodiment contains a compound (C) in which a copolymer of an α-olefin having 5 to 60 carbon atoms and maleic anhydride is esterified with a long-chain fatty alcohol having 5 to 25 carbon atoms. ..

By using the compound (C), the coagulation and consolidation (blocking property) of the resin molding material is suppressed, so that the fluidity and the releasability from the mold are excellent, and the occurrence of burrs during molding is reduced. Will be done. In other words, the balance of these characteristics is excellent. Further, by using the compound (C), it is possible to obtain a molded product having excellent magnetic properties such as magnetic permeability and mechanical strength.

Compound (C) can be obtained, for example, by the following steps.
Step (a): Copolymerization of α-olefin having 5 to 60 carbon atoms and maleic anhydride to obtain a copolymer Step (b): The copolymer obtained in step (a) and the number of carbon atoms Step of esterifying 5 to 25 long-chain fatty alcohols in the presence of trifluoromethanesulfonic acid

(Step (a))
Examples of the α-olefin having 5 to 60 carbon atoms used in the step (a) include 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-octadecene, 1-eicosene, 1 -Dodecene, 1-Tetracontene, 1-Hexacontene, 1-Octene, 1-Triacontene, 1-Hentria Conten, 1-Dodecene Conten, 1-Tritoria Contene, 1-Tetratriacontene, 1-Pentatoria Contene, 1-hexatria content, 1-tetraconten, 1-hentetraconten, 1-dodeceneconten, 1-tritetracontene, 1-tetratetracontene, 1-pentaconten, 1-henpentaconten, 1- Linear 1-alkenes such as dopentene content, 1-tripenta content, 1-penta penta content, 1-hexa content, 1-hepta content, 1-octa content, 3-methyl-1-tria content, 3, Examples thereof include branched 1-alkenes such as 4-dimethyl-triacontene, 3-methyl-1-tetracontene, and 3,4-dimethyl-tetracontene, and these may be used alone or in combination of two or more. You may.

Examples of the copolymer of the α-olefin having 5 to 60 carbon atoms and maleic anhydride obtained in the above step (a) include compounds having the structures represented by the formulas (e) and (f). As a commercial product, Diacarna (registered trademark) 30 (registered trademark) 30 (manufactured by Mitsubishi Chemical Co., Ltd.) using 1-octacosen, 1-triaconten, 1-tetraconten, 1-pentacontene, 1-hexaconten, etc. as raw materials First name).

R in the general formulas (e) and (f) represents an aliphatic hydrocarbon group having 3 to 58 carbon atoms, and n is an integer of 1 or more. m represents the copolymerization molar ratio a / b of the α-olefin (a) and maleic anhydride (b), and is 1/2 to 10/1, preferably 1/2 to 5/1. It is more preferably 1/2 to 2/1, and further preferably about 1/1 of about equimolar.

The method for producing a copolymer of α-olefin and maleic anhydride is not particularly limited, and a general copolymerization method such as reacting raw materials can be used. An organic solvent or the like capable of dissolving α-olefin and maleic anhydride may be used for the reaction. The organic solvent is not particularly limited, but toluene is preferable, and aromatic solvents, ether solvents, halogen solvents and the like can also be used. The reaction temperature varies depending on the type of organic solvent used, but is preferably 50 to 200 ° C., more preferably 100 to 150 ° C. from the viewpoint of reactivity and productivity. The reaction time is not particularly limited as long as the copolymer can be obtained, but is preferably 1 to 30 hours, more preferably 2 to 15 hours, still more preferably 4 to 10 hours from the viewpoint of productivity. After completion of the reaction, unreacted components, solvents and the like can be removed, if necessary, under heating and reduced pressure. The conditions are such 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 0.5 to 10 hours. Is preferable. In addition, a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or benzoyl peroxide (BPO) may be added to the reaction, if necessary.

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

Examples of long-chain aliphatic alcohols having 5 to 25 carbon atoms include pentyl alcohols, hexyl alcohols, octyl alcohols, decyl alcohols, lauryl alcohols, myristyl alcohols, cetyl alcohols, stearyl alcohols, eicosyl alcohols, behenyl alcohols, and 2-methyl-. Linear or branched long-chain aliphatic saturated alcohols such as decane-1-ol, 2-ethyl-decane-1-ol, 2-hexyl-octane-1-ol, hexenol, 2-hexen-1-ol. Examples thereof include linear or branched long-chain aliphatic unsaturated alcohols such as oar, 1-hexen-3-ol, pentenol and 2-methyl-1-pentenol, and even if these are used alone, 2 You may use a combination of seeds or more. Among these, a linear alcohol having 10 to 25 carbon atoms is preferable, and a linear aliphatic saturated alcohol having 15 to 20 carbon atoms is more preferable from the viewpoint of blocking property at the time of molding.

The amount of trifluoromethanesulfonic acid is preferably 100 ppm or more and 1000 ppm or less with respect to 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 obtained esterified product may be oxidized. Oxides of esterified products tend to reduce continuous moldability.

The molar ratio of the copolymer obtained in the step (a) to the alcohol having 5 to 25 carbon atoms is not particularly limited and can be set arbitrarily. However, by adjusting this reaction molar ratio, the esterified product can be prepared. Since it is possible to control the degree of hydrophilicity, it is preferable to appropriately set it according to the semiconductor encapsulant to be applied. An organic solvent or the like capable of dissolving α-olefin and maleic anhydride may be used for the reaction. The organic solvent is not particularly limited, but toluene is preferable, and aromatic solvents, ether solvents, halogen solvents and the like can also be used. The reaction temperature varies depending on the type of organic solvent used, but is preferably 50 to 200 ° C., more preferably 120 to 170 ° C. from the viewpoint of reactivity and productivity. The reaction time is not particularly limited as long as the copolymer can be obtained, but is preferably 1 to 30 hours, more preferably 2 to 30 hours, still more preferably 4 to 28 hours from the viewpoint of productivity. After completion of the reaction, unreacted components, solvents and the like can be removed, if necessary, under heating and reduced pressure. The conditions are such 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 0.5 to 10 hours. Is preferable.

The compound obtained by esterifying a copolymer of α-olefin and maleic anhydride with the above alcohol having 5 to 25 carbon atoms is at least one repeating unit selected from the formulas (a) to (d). Can contain at least one compound (c1) comprising.

In the formulas (a) to (d), R represents an aliphatic hydrocarbon group having 3 to 58 carbon atoms, R ² represents a long-chain aliphatic hydrocarbon group having 5 to 25 carbon atoms, and m is the α. -The copolymer molar ratio a / b of the olefin (a) and the maleic anhydride (b) is shown, which is 1/2 to 10/1, and n is an integer of 1 or more.

The compound (c1) contains (1) any one of the formulas (a) to (d) alone in the main clavicle, and (2) any of the formulas (a) to (d) in the main clavicle. Or two or more kinds are randomly included, regularly included, or contained in a block shape, etc., and these may be contained alone or as a mixture of two or more kinds.

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 further preferably 90% or more.

The reaction mixture containing the esterified product obtained in the step (b) may contain an α-olefin present unreacted in the step (a).

The number average molecular weight of the esterified product obtained by the method of the present invention is preferably 2,000 to 10,000. Within the above range, the coagulation and consolidation (blocking property) of the resin molding material is further improved, the fluidity and the mold releasability from the mold are improved, and the generation of burrs during molding is further reduced. ..

The content of the compound (C) is preferably 0.01 to 3% by mass, more preferably 0.05 to 2% by mass in the entire resin molding material.
The content of the compound (C) is preferably 0.03 to 15% by volume, preferably 0.1 to 10% by volume in the entire resin molding material.
As a result, the coagulation and consolidation (blocking property) of the resin molding material is further improved, the fluidity and the mold releasability from the mold are improved, and the generation of burrs during molding is further reduced. Further, it is possible to obtain a molded product having excellent magnetic properties such as magnetic permeability and mechanical strength.

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

Examples of the constituent material of the soft magnetic particles (D) include a metal-containing material having an iron content of 85% by mass or more as a constituent element. Such a metal material having a high iron content as a constituent element exhibits soft magnetism having relatively good magnetic properties such as magnetic permeability and magnetic flux density. Therefore, for example, a resin molding material capable of exhibiting good magnetic properties when molded into a magnetic core or the like can be obtained.

Examples of the form of the metal-containing material include simple substances, solid solutions, eutectic systems, alloys such as intermetallic compounds, and the like. By using the particles made of such a metal material, it is possible to obtain 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.

Moreover, the above-mentioned metal-containing material may contain an element other than iron as a constituent element. Elements other than iron include, for example, B, C, N, O, Al, Si, P, S, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Cd. , In, Sn and the like, and one or a combination of two or more of these is used. In the present embodiment, one or more kinds of elements selected from Fe, Ni, Si and Co can be contained as a main element.

Specific examples of the above metal-containing materials include pure iron, silicon steel, iron-cobalt alloy, iron-nickel alloy, iron-chromium alloy, iron-aluminum alloy, carbonyl iron, stainless steel, or any of these. Examples thereof include composite materials containing one type or two or more types. Silicon steel and carbonyl iron can be preferably used from the viewpoint of availability.
The soft magnetic particles (Fe-based soft magnetic particles) may be other particles. For example, it may be a magnetic particle containing Ni-based soft magnetic particles, Co-based soft magnetic particles, and the like.

The resin molding material of the present embodiment has a soft magnetic particle (D) content of 85% by mass or more and 98% by mass or less, preferably 86% by mass or more and 98% by mass or less, preferably 90% by mass or more and 97% by mass or less. Can be included in quantity.
The resin molding material of the present embodiment contains the soft magnetic particles (D) in an amount of 70% by volume or more and 90% by volume or less, preferably 70% by volume or more and 85% by volume or less, and more preferably 75% by volume or more and 85% by volume or less. include. As a result, a magnetic material having a high saturation magnetic flux density can be obtained.

(Curing catalyst)
The resin molding material of the present embodiment preferably contains a curing catalyst. The curing catalyst is sometimes called a curing accelerator or the like. The curing catalyst is not particularly limited as long as it accelerates the curing reaction of the epoxy resin, and a known epoxy curing catalyst can be used.

Specifically, phosphorus atom-containing compounds such as organic phosphine, tetra-substituted phosphonium compound, phosphobetaine compound, adduct of phosphine compound and quinone compound, adduct of phosphonium compound and silane compound; imidazole such as 2-methylimidazole. Classes (imidazole-based curing accelerators); 1,8-diazabicyclo [5.4.0] Undecene-7, benzyldimethylamine and the like, examples of amidine and tertiary amines, and nitrogen atoms such as amidine and quaternary salts of amines. Examples include contained compounds.
When a curing catalyst is used, only one type may be used, or two or more types may be used.

When a curing catalyst is used, its content is preferably 0.01 to 1% by mass, more preferably 0.05 to 0.8% by mass, based on the entire resin molding material. By setting such a numerical range, a sufficient curing accelerating effect can be obtained without excessively deteriorating other performances.

(Other ingredients)
The resin molding material of the present embodiment may contain components other than the above-mentioned components. For example, the resin molding material of the present embodiment may contain a low stress agent, a coupling agent, an adhesion aid, a colorant, an antioxidant, an anticorrosion, a dye, a pigment, a flame retardant and the like.

Examples of the low stress agent include silicone compounds such as polybutadiene compounds, acrylonitrile butadiene copolymer compounds, silicone oils, and silicone rubbers. When a low stress agent is used, only one type may be used, or two or more types may be used in combination.

As the coupling agent, the above-mentioned coupling agent used for surface treatment of magnetic particles can be used. For example, a silane-based coupling agent, a titanium-based coupling agent, a zirconia-based coupling agent, an aluminum-based coupling agent, and the like can be mentioned. When a coupling agent is used, only one type may be used, or two or more types may be used in combination.

(Manufacturing method of resin molding material)
Industrially, for example, the resin molding material of the present embodiment first (1) mixes each component using a mixer, and (2) then uses a roll at about 120 ° C. for 5 minutes or more, preferably. It can be produced by kneading for about 10 minutes to obtain a kneaded product, (3) and cooling the obtained kneaded product, and (4) further pulverizing the kneaded product. From the above, a powdery resin molding material can be obtained. Since the powdery resin molding material of the present embodiment suppresses coagulation and consolidation, it has excellent fluidity and improved handleability.

The powdery resin molding material may be tableted into a tablet. As a result, a resin molding material particularly suitable for use in a transfer molding method or a compression molding method can be obtained.

(Form of resin molding material)
The resin molding material of the present embodiment is preferably in the form of tablets or granules at 23 ° C., and more preferably in the form of tablets. The powdery resin molding material can be tableted to form a tablet. Since the resin molding material is in the form of tablets or granules, it is easy to distribute and store the resin molding material, and it is easy to apply it to transfer molding and compression molding.
The powdery resin molding material of the present embodiment is suppressed from agglutination and consolidation, and can be a tablet-like or granular composition having a uniform composition.

(Characteristics when the resin molding material is melted)
Since the resin molding material of the present embodiment contains the compound (C), the fluidity of the resin molding material at the time of melting can be improved, and the moldability and the like can be improved.

Specifically, the melt viscosity measured at a temperature of 175 ° C. using a constant load thin tube extrusion rheometer (flow tester) is preferably 0.1 to 200 Pa · s, more preferably 0.1 to 180 Pa. · S, more preferably 0.1 to 150 Pa · s.

As the constant load thin tube extrusion 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 (392N).

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

In the spiral flow test, for example, a low-pressure transfer molding machine (“KTS-15” manufactured by Kotaki Seiki Co., Ltd.) is used to inject into a mold for measuring spiral flow according to EMMI-1-66 at a mold temperature of 175 ° C. This can be done by injecting a resin molding material under the conditions of a pressure of 6.9 MPa and a curing time of 120 seconds, and measuring the flow length.
The resin molding material of the present embodiment can have a gelation time of 5 seconds or more and 300 seconds or less, preferably 10 seconds or more and 200 seconds or less at 175 ° C.

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 of a coil (large structure) such as a vehicle-mounted reactor can be improved, and the gelation time can be set to be equal to or lower than the above upper limit value. By doing so, it is possible to suppress the occurrence of variation in magnetic permeability and enhance the magnetic characteristics.

(Glass transition temperature of cured product)
The glass transition temperature of the cured product obtained by melting the resin molding material of the present embodiment at 175 ° C. and curing it in the air at 175 ° C. for 4 hours is preferably 150 to 220 ° C., more preferably. Is 160-200 ° C. By designing the resin molding material so that the glass transition temperature is 150 ° C. or higher, it is easy to clear the heat resistance required for in-vehicle use, for example. 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.

<Molded product>
The molded product of this embodiment can be obtained by curing the above-mentioned resin molding material. Since the powdery resin molding material of the present embodiment suppresses coagulation and consolidation, the composition of the obtained molded product (magnetic material) is uniform, and magnetic properties such as magnetic permeability or saturation magnetic flux density and the machine It is possible to exhibit desired characteristics in terms of target strength and the like.

Since the molded product of the present embodiment has a uniform composition as described above, magnetic flux can easily pass through (magnetization is easy), and the relative magnetic permeability can be 15 or more, preferably 20 or more.

Further, since the molded product of the present embodiment has a uniform composition as described above and is composed of a composite material having a high saturation magnetic flux density, a high saturation magnetic flux density can be realized, and 1.0 T or more. It can be preferably 1.2 T or more, more preferably 1.3 T or more.
The method for producing the molded product is not particularly limited, and examples thereof include a transfer molding method and a compression molding method.

(Transfer molding method)
The method for manufacturing a molded product by the transfer molding method includes a step of injecting a melt of the above-mentioned resin molding material into a mold using a transfer molding apparatus, a step of curing the melt, and a step of curing the melt from the mold. Including the step of removing the mold.

The transfer molding can be performed by appropriately using a known transfer molding apparatus. Specifically, first, the preheated resin molding material is placed in a heating chamber, which is also called a transfer chamber, and melted to obtain a melt. Then, the melt is poured into a 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 in shape.

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

(Compression molding method)

A method for producing a molded product by a compression molding method (compression molding method) includes a step of compression molding the resin molding material. Specifically, it includes a step of compression molding the resin molding material of the present embodiment in a mold and a step of separating the molded product from the mold.

The compression molding can be carried out by appropriately using a known compression molding apparatus. Specifically, the resin molding material is placed in the concave portion of the concave fixed mold that opens upward. The resin molding material can be preheated. As a result, the molded product can be uniformly cured, and the molding pressure can be lowered.

Next, from above, the 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 sufficiently softened and flowed at a low pressure, then the mold is closed and pressed again to cure for a predetermined time.

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

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

<Examples 1 and 2, Comparative Examples 1 and 2>
Each component listed in Table 1 was prepared in the ratio described and mixed uniformly to obtain a mixture.
The resulting mixture was then kneaded at 120 ° C. for 10 minutes. After completion of kneading, the obtained kneaded product was cooled to room temperature to be solidified, and then pulverized to obtain a powdery resin molding material. Further, the obtained powdery resin molding material was tablet-molded to obtain a tablet-shaped resin molding material.
The raw material components listed 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 (volume%) of the magnetic particles shown in Table 1 is the content (that is, the filling rate) when the resin molding material containing the soft magnetic particles is 100% by volume.

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

(Hardener)
Hardener 1: PR-HF-3: Novolac-type phenol resin manufactured by Sumitomo Bakelite Co., Ltd., solid at 23 ° C Hardener 2: MEH-7851SS (biphenylene skeleton-containing phenol aralkyl resin manufactured by Meiwa Kasei Co., Ltd., solid at 23 ° C) )

(Release agent (wax))
Synthesis of mold release agent 1 100.0 g of a copolymer of 1-alkene having 28 to 60 carbon atoms and maleic anhydride (Diacarna R30, manufactured by Mitsubishi Chemical Co., Ltd.) and 47.0 g of stearyl alcohol were added to 300 ml of 4 The mixture was placed in a separable flask and dissolved at 70 ° C., and then 0.5 g of a 10 wt% trifluoromethanesulfonic acid aqueous solution was added. The resulting reaction mixture was stirred at 150 ° C. for 5 hours.
Then, the liquid temperature was cooled to 120 ° C., and the liquid was distilled under reduced pressure for 2 hours under a reduced pressure of 30 Torr to remove free trifluoromethanesulfonic acid and water to obtain 144 g of a release agent 1 as an esterified product. rice field.
Release agent 2: Recoble WE-4: Ester wax manufactured by Clariant Chemicals Co., Ltd. Release agent 3: Lycowax PED1911: Polyethylene oxide wax manufactured by Clariant Chemicals Co., Ltd.

(Curing catalyst)
Curing catalyst 1: Tetraphenylphosphonium 4,4'-sulfonyl diphenolate Curing catalyst 2: Tetraphenylphosphonium bis (naphthalene-2,3-dioxy) phenyl silicate

(Soft magnetic particles)
Iron-based particles 1: Amorphous magnetic powder (manufactured by Epson Atmix Co., Ltd., KUAMET6B2 150C01, median diameter D ₅₀ : 50 μm)
Iron-based particles 2: Amorphous magnetic powder (manufactured by Epson Atmix Co., Ltd., AW2-08 PF3FG, median diameter D ₅₀ : 3.4 μm)

<Evaluation>
(Agglutination and consolidation of resin molding material (blocking property))
20 g of powdered resin molding material is placed in an aluminum cup having a diameter of 55 mm so as to have a height of 5 mm, stored at a temperature of 25 ° C. and a humidity of 55% for 24 hours, and then the resin molding material is spread on a plate and solidified in the powder. The presence or absence of a bond was visually confirmed, and the blocking property was evaluated according to the following evaluation criteria.
Note that FIG. 1 shows a photograph of the resin molding material after the test in Comparative Example 2.
<Evaluation criteria for blocking property>
◯: No solidified material of 2 mm or more is observed in the powdered resin molding material.
Δ: No solidified product of 10 mm or more is observed in the powdered resin molding material.
X: Consolidation of 10 mm or more is observed in the powdered resin molding material.

(Liquidity: Spiral flow test)
A spiral flow test was performed using the resin molding materials of Examples and Comparative Examples.
In the test, a low-pressure transfer molding machine (“KTS-15” manufactured by Kotaki Seiki Co., Ltd.) was used to mold for spiral flow measurement according to EMMI-1-66, with a mold temperature of 175 ° C and an injection pressure of 6. This was performed by injecting a resin molding material under the conditions of 9. MPa and a curing time of 120 seconds, and measuring the flow length. The larger the value, the better the fluidity.

(Releasability)
The test was performed using a low-pressure transfer molding machine (“KTS-30” manufactured by Kotaki Seiki Co., Ltd.) with a mold temperature of 175 ° C., an injection pressure of 9.8 MPa, and a curing time of 120 seconds. When the molded product was taken out from the mold, the molded product was confirmed to be damaged, and the releasability was evaluated according to the following evaluation criteria.
<Evaluation criteria for releasability>
◯: No damage was observed in the molded product when the molded product was taken out from the mold.
X: When the molded product was taken out from the mold, damage was observed in the molded product.

(Generation of molding burrs)
In the test, a low-pressure transfer molding machine (“KTS-15” manufactured by Kotaki Seiki Co., Ltd.) was used to mold for spiral flow measurement according to EMMI-1-66, with a mold temperature of 175 ° C and an injection pressure of 6. After injecting the resin molding material under the conditions of 9. MPa and a curing time of 120 seconds, the presence or absence of the resin exuded to the upper part of the plunger was visually confirmed, and the occurrence of molding burrs was evaluated according to the following evaluation criteria.
<Evaluation criteria for molding burrs>
◯: No resin is found on the upper part of the plunger.
X: Resin is found on the upper part of the plunger.

From the results in Table 1, the resin molding material of the example to which the compound (C) was added was suppressed from coagulation and consolidation (blocking property). From this, it was presumed that the resin molding material of the example was excellent in handleability, the composition of the molded product obtained by curing the resin molding material was uniform, and the desired characteristics could be exhibited. Furthermore, it was confirmed that the fluidity and the releasability from the mold were excellent, and that the generation of burrs during molding was reduced, that is, the balance between them was excellent.

Claims (10)

(A) Thermosetting resin and
(B) Hardener and
(C) A compound obtained by esterifying a copolymer of an α-olefin having 5 to 60 carbon atoms and maleic anhydride with a long-chain fatty alcohol having 5 to 25 carbon atoms.
(D) Soft magnetic particles and
Including resin molding materials. The resin molding material according to claim 1, wherein the compound (C) contains at least one compound having at least one repeating unit selected from the following formulas (a) to (d).

(In formulas (a) to (d), R represents an aliphatic hydrocarbon group having 3 to 58 carbon atoms, R ² represents a long-chain aliphatic hydrocarbon group having 5 to 25 carbon atoms, and m is the above. The copolymerization molar ratio a / b of the α-olefin (a) and the maleic anhydride (b) is shown to be 1/2 to 10/1, and n is an integer of 1 or more.) The resin molding material according to claim 1 or 2, wherein the content of the soft magnetic particles (D) is 85% by mass or more and 98% by mass or less. The resin molding material according to any one of claims 1 to 3, wherein the soft magnetic particles (D) contain one or more elements selected from Fe, Ni, Si and Co. The resin molding material according to any one of claims 1 to 4, wherein the thermosetting resin (A) contains an epoxy resin. The resin molding material according to any one of claims 1 to 5, wherein the curing agent (B) contains a phenol-based curing agent. The resin molding material according to any one of claims 1 to 6, which is in the form of tablets or granules at 23 ° C. A molded product obtained by curing the resin molding material according to any one of claims 1 to 7. A step of injecting a melt of the resin molding material according to any one of claims 1 to 7 into a mold using a transfer molding apparatus.
The process of curing and molding the melt and
The process of releasing the molded product from the mold and
A method for manufacturing an article, including. A step of compression molding the resin molding material according to any one of claims 1 to 7 in a mold.
The process of releasing the molded product from the mold and
A method for manufacturing an article, including.

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