Resin composition and molded article

Abstract

Provided are: a new resin composition from which it is possible to obtain a molded article that does not exhibit draw‑down when exposed to air having a high temperature exceeding the melting point of a thermoplastic resin; and a molded article thereof.　This resin composition contains a thermoplastic resin (A) and a draw-down inhibitor (B) containing an inorganic filler (b2) and an epoxy group- and / or glycidyl group-containing polymer (b1), and satisfies any of specific conditions (I)-(III). The polymer (b1) preferably includes at least one selected from an epoxy group- and / or glycidyl group-containing olefin-based copolymer (b11) and an epoxy resin (b12).

Description

Resin composition and molded article

[0001] This disclosure relates to resin compositions and molded articles thereof.

[0002] Batteries (storage batteries), such as lead-acid batteries, nickel-metal hydride batteries, NAS batteries, and lithium-ion batteries, can be recharged and discharged, allowing for repeated use. Batteries are widely used as power sources for electronic devices such as personal computers and mobile phones, but in recent years, high-capacity, high-output batteries have been developed for use in vehicles such as electric vehicles (EVs), homes, and infrastructure.

[0003] Lithium-ion batteries are configured as battery modules having multiple cells (for example, Patent Document 1, etc.), and there is a growing need for resin materials that offer high flexibility in shape and enable weight reduction as related components of these lithium-ion batteries. In recent years, due to the increase in the number of cells accompanying the improvement in energy density of lithium-ion batteries, and changes in the arrangement of control boards, the modules have become larger and more complex. As a result, the shapes of the exterior components (for example, housings such as upper covers) and interior components of lithium-ion batteries have also become more complex, making the shift to resin materials even more urgent.

[0004] Incidentally, batteries can experience thermal runaway, which can lead to accidents such as the battery overheating or catching fire. When a battery experiences thermal runaway, a "drawdown" occurs where the components and casing surrounding the battery become so hot that they melt, and this can spread to the surrounding area and cause a fire. Lithium-ion batteries, in particular, are prone to thermal runaway caused by internal or external short circuits where the positive and negative electrodes make electrical contact inside or outside the cell. Furthermore, because lithium-ion batteries contain flammable materials, there is a problem that the heat generated by thermal runaway can easily cause a fire.

[0005] Patent Document 2 proposes a composite material in which the surface of an insulating material such as urethane foam or polystyrene foam is coated with a mica sheet, which can be applied to interior components (e.g., insulating components or heat-shielding components) to protect adjacent cells from radiant heat caused by cell thermal runaway. However, such composite materials have the problems of high manufacturing costs and low degree of shape freedom. If the mica sheet is omitted from the viewpoint of cost reduction and shape freedom, the urethane foam or polystyrene foam will draw down during the aforementioned thermal runaway.

[0006] In the field of resin materials, including thermoplastic resins, various resin materials have been proposed that offer improved resistance to thermal loads, such as heat resistance, flame retardancy, heat shock resistance, and impact resistance. However, these properties are entirely different from "drawdown resistance." In other words, these properties evaluate resistance to thermal loads at temperatures below the melting point of the thermoplastic resin contained in the resin material, and do not evaluate resistance when exposed to high-temperature conditions exceeding the melting point. It is common technical knowledge that molded articles made from resin materials containing thermoplastic resins will draw down when exposed to a high-temperature atmosphere exceeding the melting point of the thermoplastic resin, and there has been no known instance of a "resin molded article with drawdown resistance" that does not draw down even when exposed to a high-temperature atmosphere exceeding the melting point.

[0007] International Publication No. 2014 / 141765, Japanese Patent Publication No. 2021-163538

[0008] The object of this disclosure is to provide a novel resin composition and a molded article thereof that does not undergo drawdown when exposed to a high-temperature atmosphere exceeding the melting point of the thermoplastic resin.

[0009] As a result of diligent study, the inventors of the present invention have determined that a drawdown inhibitor (B) comprises a thermoplastic resin (A), an epoxy group and / or glycidyl group-containing polymer (b1), and an inorganic filler (b2), and the following (I): (I) comprising a fibrous inorganic filler (b21) as the inorganic filler (b2), comprising 8 parts by mass or more of the polymer (b1) and 50 parts by mass or more of the fibrous inorganic filler (b21) per 100 parts by mass of the thermoplastic resin (A), the following (II): (II) comprising 8 parts by mass or more of the polymer (b1) and 200 parts by mass or more of the inorganic filler (b2) per 100 parts by mass of the thermoplastic resin (A), We have found that the above problem can be solved with a resin composition that satisfies the following conditions: it contains 8 parts by mass or more of the polymer (b1), 39 parts by mass or more but less than 50 parts by mass of the fibrous inorganic filler (b21), and 115 parts by mass or more but less than 200 parts by mass of the inorganic filler (b2).

[0010] According to this disclosure, it is possible to provide a novel resin composition and a molded article thereof that does not undergo drawdown when exposed to a high-temperature atmosphere exceeding the melting point of the thermoplastic resin.

[0011] These are photographs showing the fixture used for evaluating drawdown resistance and the condition of the test specimen before testing. This is a photograph showing the condition of the test specimen after the drawdown resistance evaluation of Example 1. This is a photograph showing the condition of the test specimen after the drawdown resistance evaluation of Comparative Example 1.

[0012] The following describes in detail one embodiment of the present disclosure. The present disclosure is not limited to the following embodiment and can be implemented with appropriate modifications, provided that these modifications do not impede the effects of the present disclosure. Each configuration and combination thereof in each embodiment is an example, and additions, omissions, substitutions, and other modifications can be made as appropriate, provided that these modifications do not deviate from the spirit of the present disclosure. The present disclosure is not limited by the embodiments. Each aspect disclosed herein can be combined with any other features disclosed herein. Where a particular description given for one embodiment also applies to another embodiment, that description may be omitted in the other embodiments. In this disclosure, the expression "X to Y" for numerical ranges means "X or greater and Y or less".

[0013] [Resin Composition] The first embodiment of the present disclosure relates to a resin composition. The resin composition according to the first embodiment comprises a thermoplastic resin (A), a drawdown inhibitor (B) comprising an epoxy group and / or glycidyl group-containing polymer (b1), and an inorganic filler (b2), and is as follows: (I) (I) comprising a fibrous inorganic filler (b21) as the inorganic filler (b2), comprising 8 parts by mass or more of the polymer (b1) and 50 parts by mass or more of the fibrous inorganic filler (b21) per 100 parts by mass of the thermoplastic resin (A), (II) (II) comprising 8 parts by mass or more of the polymer (b1) and 200 parts by mass or more of the inorganic filler (b2) per 100 parts by mass of the thermoplastic resin (A), The resin composition satisfies the following conditions: it contains 8 parts by mass or more of the polymer (b1), 39 parts by mass or more but less than 50 parts by mass of the fibrous inorganic filler (b21), and 115 parts by mass or more but less than 200 parts by mass of the inorganic filler (b2). According to the resin composition of the first embodiment, a molded article can be obtained that does not draw down when exposed to a high-temperature atmosphere exceeding the melting point of the thermoplastic resin.

[0014] <Thermoplastic Resin (A)> The resin composition according to the first embodiment includes a thermoplastic resin (A) (hereinafter sometimes referred to as "resin (A)"). Resin (A) is not particularly limited, and conventionally known thermoplastic resins can be used. Examples include polyolefin resins, vinyl alcohol resins, vinyl ester resins, polyester resins, polyamide resins, polyimide resins, polyamide-imide resins, polyetherimide resins, polyacetal resins, polyarylene sulfide resins, polysulfone resins, polyethersulfone resins, polyphenylsulfone resins, modified polyphenylene ether resins, polyetherketone resins, polyetheretherketone resins, liquid crystal resins, fluororesins, cyclic olefin resins (cyclic olefin polymers, cyclic olefin copolymers, etc.), silicone polymers, vinyl chloride resins, styrene resins, (meth)acrylic resins, thermoplastic elastomers (however, limited to thermoplastic elastomers that can be melt-extruded or injection-molded alone), biodegradable resins, biomass resins, etc. These may be used individually or in combination of two or more.

[0015] In one preferred embodiment, from the viewpoint of easily obtaining molded articles with excellent mechanical properties, electrical properties, heat resistance, and other physical properties, it is preferable that the resin (A) includes a polyarylene sulfide resin (a1) or a polyester resin. Examples of polyester resins include C2 to C6 alkylene arylate resins such as polyethylene terephthalate resin (PET), polyethylene naphthalate resin (PEN), polytrimethylene terephthalate resin (PTT), and polybutylene terephthalate resin (PBT), and it is preferable that the resin (A) includes a polybutylene terephthalate resin (a2). In a more preferred embodiment, the resin (A) includes a polyarylene sulfide resin (a1) or a polybutylene terephthalate resin (a2). A preferred embodiment of the polyarylene sulfide resin (a1) and the polybutylene terephthalate resin (a2) will be described below.

[0016] (Polyarylene sulfide resin (a1)) The resin composition according to the first embodiment may include a polyarylene sulfide resin (a1) as resin (A). The polyarylene sulfide resin (a1) (hereinafter sometimes referred to as "resin (a1)") is characterized by excellent mechanical properties, electrical properties, heat resistance, and other physical and chemical properties, as well as good processability. The resin (a1) in this disclosure is a resin having repeating units represented by the following general formula (1): - (Ar １ -S)-...(1) (In general formula (1), Ar １ (This represents an arylene group which may have substituents.)

[0017] The arylene group in formula (1) is not particularly limited, but examples include p-phenylene group, m-phenylene group, o-phenylene group, substituted phenylene group, p,p'-diphenylene sulfone group, p,p'-biphenylene group, p,p'-diphenylene ether group, p,p'-diphenylene carbonyl group, naphthalene group, etc. The resin (a1) can be a homopolymer containing only the same repeating units from the repeating units represented by the general formula (1) above, or a copolymer containing different types of repeating units.

[0018] As a homopolymer, one having a p-phenylene group as the arylene group and consisting of repeating p-phenylene sulfide groups is preferred. Homopolymers with repeating p-phenylene sulfide groups have extremely high heat resistance and can exhibit high strength, high rigidity, and high dimensional stability over a wide temperature range.

[0019] As the copolymer, any combination of two or more different arylene sulfide groups, including the arylene group described above, can be used. Among these, a combination containing a p-phenylene sulfide group and an m-phenylene sulfide group is preferred from the viewpoint of easily obtaining molded articles with good physical properties such as heat resistance, moldability, and mechanical properties. Of these, polymers containing 70 mol% or more of p-phenylene sulfide groups are more preferred, and polymers containing 80 mol% or more are even more preferred.

[0020] Resin (a1) is generally known to have a molecular structure that is substantially linear and does not have branching or crosslinking structures (linear structure), or a structure that has branching or crosslinking structures, depending on the manufacturing method. In one embodiment, from the viewpoint of the mechanical properties of the molded product, a linear structure is more preferable. In addition to the linear structure resin (a1), polymers can also be used in which a small amount of monomer such as a polyhalo-substituted aromatic compound having three or more halogen substituents is used during polycondensation to form a partially branched or crosslinked structure, or polymers in which the melt viscosity is increased by oxidative crosslinking or thermal crosslinking by heating a low molecular weight linear structure polymer at a high temperature in the presence of oxygen, etc., to improve moldability.

[0021] In one embodiment, the weight-average molecular weight (Mw) of resin (a1) is preferably 10,000 to 80,000, and more preferably 20,000 to 80,000. If Mw is within the above range, molded articles with good mechanical properties are easily obtained. The Mw of resin (a1) can be measured by the following method. Resin (a1) may be used alone or in combination of two or more types, but if resin (a1) is a mixture of two or more types, it is preferable that the Mw of the mixture is within the above range. (Method for measuring Mw) 1-chloronaphthalene is used as the solvent, and it is heated and dissolved in an oil bath at 250°C for 6 minutes. If necessary, it is purified by high-temperature filtration to prepare a 0.05 mass% concentration solution. High-temperature gel permeation chromatography is performed and the weight-average molecular weight is calculated on a standard polystyrene basis. As a measuring device, for example, a product name "SSC-7000" manufactured by Senshu Kagaku Co., Ltd., with a UV detector (detection wavelength: 360 nm) can be used.

[0022] When resin (a1) is included, the ratio of resin (a1) to the total mass of resin (A) is preferably 80% by mass or more, and more preferably 90 to 100% by mass.

[0023] (Polybutylene terephthalate resin (a2)) The resin composition according to the first embodiment may include polybutylene terephthalate resin (a2) (hereinafter sometimes referred to as "resin (a2)") as resin (A). Preferably, resin (a2) is a resin obtained by polycondensation of a dicarboxylic acid component containing at least terephthalic acid or its ester-forming derivative (for example, C1-C6 alkyl esters or acid halides, etc.) and a glycol component containing a C4 alkylene glycol such as 1,4-butanediol or its ester-forming derivative (for example, acetylated compounds, etc.). In one embodiment, resin (a2) is not limited to homopolybutylene terephthalate, but may also be a copolymer containing 60 mol% or more of butylene terephthalate units.

[0024] The amount of terminal carboxyl groups in resin (a2) is not particularly limited as long as it does not hinder the purpose of this disclosure, but in one embodiment, it is preferably 30 meq / kg or less, and more preferably 25 meq / kg or less.

[0025] The intrinsic viscosity (IV) of resin (a2) is not particularly limited as long as it does not hinder the purpose of this disclosure, but in one embodiment, it is preferably 0.60 dL / g or more and 1.3 dL / g or less, and more preferably 0.65 dL / g or more and 1.0 dL / g or less. When resin (a2) with an intrinsic viscosity in this range is included, moldability tends to be better. Furthermore, the intrinsic viscosity can be adjusted by blending resins (a2) having different intrinsic viscosities. For example, a resin (a2) with an intrinsic viscosity of 0.9 dL / g can be prepared by blending a polybutylene terephthalate resin with an intrinsic viscosity of 1.0 dL / g and a polybutylene terephthalate resin with an intrinsic viscosity of 0.7 dL / g. The intrinsic viscosity of resin (a2) can be measured, for example, in o-chlorophenol at a temperature of 35°C.

[0026] In the preparation of resin (a2), when using an aromatic dicarboxylic acid other than terephthalic acid or its ester-forming derivative as a comonomer component, for example, C8-C14 aromatic dicarboxylic acids such as isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4'-dicarboxydiphenyl ether; C4-C16 alkanedicarboxylic acids such as succinic acid, adipic acid, azelaic acid, and sebacic acid; C5-C10 cycloalkanedicarboxylic acids such as cyclohexanedicarboxylic acid; and ester-forming derivatives of these dicarboxylic acid components (such as C1-C6 alkyl ester derivatives and acid halides) can be used. These dicarboxylic acid components may be used individually or in combination of two or more. Among these dicarboxylic acid components, C8-C12 aromatic dicarboxylic acids such as isophthalic acid and C6-C12 alkanedicarboxylic acids such as adipic acid, azelaic acid, and sebacic acid are more preferred.

[0027] In the preparation of resin (a2), glycol components other than 1,4-butanediol may also be used as comonomer components. Examples of glycol components other than 1,4-butanediol include C2 to C10 alkylene glycols such as ethylene glycol, propylene glycol, trimethylene glycol, 1,3-butylene glycol, hexamethylene glycol, neopentyl glycol, and 1,3-octanediol; polyalkylene glycols such as diethylene glycol, triethylene glycol, and dipropylene glycol; cyclohexanedimethanol; alicyclic diols such as hydrogenated bisphenol A; aromatic diols such as bisphenol A and 4,4'-dihydroxybiphenyl; C2 to C4 alkylene oxide adducts of bisphenol A, such as a 2-mol ethylene oxide adduct of bisphenol A and a 3-mol propylene oxide adduct of bisphenol A; or ester-forming derivatives (acetylated compounds, etc.) of these glycols. These glycol components may be used individually or in combination of two or more. Among these glycol components, C2-C6 alkylene glycols such as ethylene glycol and trimethylene glycol, polyalkylene glycols such as diethylene glycol, or alicyclic diols such as cyclohexanedimethanol are more preferred.

[0028] Other comonomer components that can be used besides the dicarboxylic acid and glycol components include, for example, aromatic hydroxycarboxylic acids such as 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, and 4-carboxy-4'-hydroxybiphenyl; aliphatic hydroxycarboxylic acids such as glycolic acid and hydroxycaproic acid; C3 to C12 lactones such as propiolactone, butyrolactone, valerolactone, and caprolactone (ε-caprolactone, etc.); and ester-forming derivatives of these comonomer components (C1 to C6 alkyl ester derivatives, acid halides, acetylated compounds, etc.).

[0029] When resin (a2) is included, the ratio of resin (a2) to the total mass of resin (A) is preferably 80% by mass or more, and more preferably 90 to 100% by mass.

[0030] <Drawdown Inhibitor (B)> The resin composition according to the first embodiment includes an epoxy group and / or glycidyl group-containing polymer (b1) and an inorganic filler (b2) comprising a drawdown inhibitor (B). The melting points of the thermoplastic resin (A) of the present disclosure are, for example, about 280°C for resin (a1) and about 225°C for resin (a2). The drawdown inhibitor (B) of the present disclosure has the function of suppressing drawdown of the molded article when the molded article is exposed to a high-temperature atmosphere at a temperature exceeding the melting point of resin (A), for example, 360°C. That is, by blending the resin composition according to the first embodiment with the drawdown inhibitor (B) to satisfy the above conditions (I), (II), or (III), a molded article that does not draw down when exposed to a high-temperature atmosphere exceeding the melting point of resin (A) can be obtained.

[0031] (Epoxy group and / or glycidyl group-containing polymer (b1)) The resin composition according to the first embodiment contains an epoxy group and / or glycidyl group-containing polymer (b1) as a drawdown inhibitor (B). The epoxy group and / or glycidyl group-containing polymer (b1) (hereinafter sometimes referred to as "component (b1)") refers to a polymer in general that contains one or more groups selected from epoxy groups and glycidyl groups in its structure. The inventors of the present invention have found that the epoxy group and / or glycidyl group-containing polymer (b1) and an inorganic filler (b2) function as agents that suppress drawdown of a molded article of a resin composition containing a thermoplastic resin (A) (preferably the above resin (a1) or resin (a2)). In one embodiment, the epoxy group and / or glycidyl group-containing polymer (b1) preferably contains one or more selected from epoxy group and / or glycidyl group-containing olefin copolymers (b11) and epoxy resins (b12).

[0032] [Epoxy group and / or glycidyl group-containing olefin copolymer (b11)] The resin composition according to the first embodiment may contain an epoxy group and / or glycidyl group-containing olefin copolymer (b11) as component (b1). The epoxy group and / or glycidyl group-containing olefin copolymer (b11) (hereinafter sometimes referred to as "component (b11)") refers to all olefin copolymers having one or more groups selected from epoxy groups and glycidyl groups in their structure, and includes olefin copolymers having glycidyl esters, glycidyl ethers, etc. in their side chains, and olefin copolymers having double bonds that have been epoxy-oxidized.

[0033] A more specific embodiment of component (b11) is, for example, an olefin copolymer obtained by copolymerizing monomers having epoxy groups and / or glycidyl groups. Examples of such olefin copolymers include glycidyl group-containing olefin copolymers obtained by copolymerizing α-olefin and glycidyl esters of α,β-unsaturated acids; maleic anhydride-modified olefin copolymers; glycidyl ether-modified olefin copolymers; and olefin-alkyl acrylate copolymers. Of these, component (b11) preferably contains one or more selected from glycidyl group-containing olefin copolymers obtained by copolymerizing α-olefin and glycidyl esters of α,β-unsaturated acids, maleic anhydride-modified olefin copolymers, and glycidyl ether-modified olefin copolymers, and more preferably contains the glycidyl group-containing olefin copolymer. That is, in one preferred embodiment of component (b11), it contains an olefin copolymer containing constituent units derived from α-olefins having two or more carbon atoms and constituent units derived from glycidyl esters of α,β-unsaturated acids.

[0034] The α-olefins having 2 or more carbon atoms (hereinafter sometimes simply referred to as "α-olefins") are not particularly limited, and examples thereof include ethylene, propylene, butylene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, 4-methyl-1-hexene and the like. Among them, it is preferable to contain ethylene. The structural unit derived from the α-olefin may be contained alone or in combination of two or more. The content of the structural unit derived from the α-olefin is not particularly limited, but can be, for example, 0.5 to 20% by mass based on the total mass of the resin composition.

[0035] Next, the structural unit derived from the glycidyl ester of α,β-unsaturated acid will be described. In the present specification, the alkyl (meth)acrylate may be described as (meth)acrylate. For example, the glycidyl (meth)acrylate may be described as the glycidyl ester of (meth)acrylic acid. In the present specification, "(meth)acrylic acid" means both acrylic acid and methacrylic acid, and "(meth)acrylate" means both acrylate and methacrylate.

[0036] The glycidyl ester of α,β-unsaturated acid (hereinafter sometimes simply referred to as "glycidyl ester") is not particularly limited, and examples thereof include those having a structure represented by the following general formula (2). [In the general formula (2), R １ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. ]

[0037] Examples of the compound represented by the general formula (2) include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, etc. Among them, glycidyl methacrylate is preferable. The structural unit derived from the glycidyl ester of α,β-unsaturated acid may be contained alone or in combination of two or more. The content of the structural unit derived from the glycidyl ester of α,β-unsaturated acid is preferably 0.02 to 2.5% by mass, more preferably 0.05 to 1.5% by mass, and particularly preferably 0.08 to 1.0% by mass based on the total mass of the resin composition.

[0038] The glycidyl group-containing olefin copolymer preferably further contains a structural unit derived from an alkyl (meth)acrylate. The alkyl (meth)acrylate is not particularly limited, and examples thereof include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-hexyl acrylate, n-amyl acrylate, n-octyl acrylate; and alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, n-amyl methacrylate, n-octyl methacrylate. Among them, methyl acrylate is particularly preferable. The structural unit derived from the above alkyl (meth)acrylate may be contained alone or in combination of two or more. The content of the structural unit derived from the alkyl (meth)acrylate is preferably 0.2 to 5.5% by mass based on the total mass of the resin composition.

[0039] The glycidyl group-containing olefin copolymer is particularly preferably a glycidyl methacrylate-modified ethylene copolymer containing ethylene-derived structural units and glycidyl methacrylate-derived structural units. Examples of glycidyl methacrylate-modified ethylene copolymers include glycidyl methacrylate graft-modified ethylene copolymer, ethylene-glycidyl methacrylate copolymer, ethylene-glycidyl methacrylate-methyl acrylate copolymer, ethylene-glycidyl methacrylate-ethyl acrylate copolymer, ethylene-glycidyl methacrylate-propyl acrylate copolymer, and ethylene-glycidyl methacrylate-butyl acrylate copolymer. Among these, from the viewpoint of drawdown resistance, one or more selected from ethylene-glycidyl methacrylate copolymer and ethylene-glycidyl methacrylate-methyl acrylate copolymer are preferred, and the inclusion of ethylene-glycidyl methacrylate-methyl acrylate copolymer is particularly preferred. Commercially available products may be used as the ethylene-glycidyl methacrylate copolymer and the ethylene-glycidyl methacrylate-methyl acrylate copolymer. For example, the "BondFirst® series" manufactured by Sumitomo Chemical Co., Ltd. can be used.

[0040] (b11) When component includes a glycidyl ether-modified ethylene copolymer, examples of the copolymer include a glycidyl ether graft-modified ethylene copolymer and a glycidyl ether-ethylene copolymer.

[0041] In one embodiment, the total amount of epoxy groups and glycidyl groups in component (b11) is preferably 100 to 1000 μmol / g, more preferably 150 to 950 μmol / g, and even more preferably 200 to 850 μmol / g, from the viewpoint of balancing drawdown resistance and moldability.

[0042] [Epoxy Resin (b12)] The resin composition according to the first embodiment may include an epoxy resin (b12) (hereinafter sometimes referred to as "component (b12)") as an epoxy group and / or glycidyl group-containing polymer (b1). The epoxy resin (b12) is a thermosetting synthetic resin having epoxy groups at its ends, and examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, brominated epoxy resin, bisphenol S type epoxy resin, diphenyl ether type epoxy resin, hydroquinone type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, fluorene type epoxy resin, bisphenol A type novolac epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, and dicyclopentadienephenol type epoxy resin. Examples include trishydroxyphenylmethane type epoxy resins, trifunctional epoxy resins, tetraphenyloleethane type epoxy resins, tetrafunctional epoxy resins, hydrogenated bisphenol A type epoxy resins, bisphenol A-containing polyol type epoxy resins, polypropylene glycol type epoxy resins, glycidyl ester type epoxy resins, glycidylamine type epoxy resins, glyoxal type epoxy resins, alicyclic epoxy resins, alicyclic polyfunctional epoxy compounds, heterocyclic epoxy resins such as triglycidyl isocyanate (TGIC), and urethane-modified epoxy resins. These may be used individually or in combination of two or more. Of these, from the viewpoint of balancing drawdown resistance and moldability, component (b12) preferably contains bisphenol A type epoxy resin or bisphenol A type novolac epoxy resin, and more preferably contains bisphenol A type epoxy resin. Furthermore, the bisphenol A type epoxy resin preferably has an epoxy equivalent of 700 to 1400 μmol / g, and more preferably 800 to 1200 μmol / g. Commercially available epoxy resins can be used for this purpose; for example, products such as "jER1004K" and "jER1004F" manufactured by Mitsubishi Chemical Corporation can be used.

[0043] In one embodiment, the total amount of epoxy groups and glycidyl groups in the resin composition is preferably 10 μmol / g or more, more preferably 10 to 500 μmol / g, even more preferably 11 to 300 μmol / g, even more preferably 12 to 200 μmol / g, and particularly preferably 13 to 100 μmol / g. By selecting component (b1) and blending it into resin (A) such that the total amount of epoxy groups and glycidyl groups in the resin composition is 10 μmol / g or more, it becomes easier to obtain molded articles that do not draw down even when exposed to a high-temperature atmosphere exceeding the melting point of resin (A).

[0044] (Inorganic filler (b2)) The resin composition according to the first embodiment includes an inorganic filler (b2) as a drawdown inhibitor (B). By blending the aforementioned epoxy group and / or glycidyl group-containing polymer (b1) and the inorganic filler (b2) in specific amounts with respect to the resin (A), the drawdown of the molded product can be suppressed. The inorganic filler (b2) (hereinafter sometimes referred to as "component (b2)") includes a specific amount of fibrous inorganic filler (b21) and / or other inorganic fillers in the resin composition. Preferably, the inorganic filler (b2) includes one or more selected from fibrous inorganic filler (b21), plate-like inorganic filler (b22), and powder-like inorganic filler (b23).

[0045] [Fibrous inorganic filler (b21)] Examples of fibrous inorganic fillers (b21) include fibrous and whisker-like fibrous inorganic fillers. These may be used individually or in combination of two or more. Examples of fibrous inorganic fillers (b21) (hereinafter sometimes referred to as "(b21) component") include glass fibers; ceramic fibers; PAN-based, pitch-based, and other carbon fibers; zirconia fibers; alumina fibers; silica fibers; silica-alumina fibers; zinc oxide fibers; titanium oxide fibers; boron nitride fibers; silicon nitride fibers; boron fibers; potassium titanate fibers; stainless steel fibers; metal fibers such as aluminum fibers and brass fibers; silicon carbide fibers; rock wool; potassium titanate whiskers; silicon nitride whiskers; wollastonite, etc. Of these, from the viewpoint of moldability, it is preferable that the (b21) component includes glass fibers. In addition, hollow fibers can be used as the fibrous inorganic filler (b21) for purposes such as reducing the specific gravity of the resin composition.

[0046] The average fiber length of component (b21) is preferably 0.01 to 3.5 mm, more preferably 0.05 to 3.5 mm, even more preferably 0.1 to 3.5 mm, and particularly preferably 0.5 to 3 mm, from the viewpoint of the mechanical properties of the resulting molded product. The average fiber length can be calculated using a scanning electron microscope and image processing software, and the arithmetic mean measured for 1000 (b21) components is used. The average fiber length can also be the manufacturer's value (a value published by the manufacturer in their catalog, etc.).

[0047] In one embodiment, the cross-sectional shape perpendicular to the longitudinal direction of the fibers of component (b21) can be a circular shape (including a nearly circular shape); an oblong, cocoon-shaped, elliptical, semicircular, rectangular, or other flattened shapes; a square, other polygons, a star shape, or other polygonal shapes; or similar shapes. Note that "cocoon-shaped" is a shape in which a part of the longitudinal direction of an oblong is indented inward. As component (b21), one type of fibrous inorganic filler having the above cross-sectional shapes may be used alone, or two or more types may be used in combination.

[0048] In one embodiment, component (b21) is preferably used with a specific gravity of 2.0 to 4.0, more preferably 2.0 to 3.5, and even more preferably 2.0 to 3.3. If the specific gravity of component (b21) is within the above range, the molded product tends to be lightweight.

[0049] In one embodiment, component (b21) may be surface-treated with various surface treatment agents such as commonly known epoxy compounds, isocyanate compounds, silane compounds, titanate compounds, and fatty acids. Surface treatment makes it easier to improve adhesion with resin (A).

[0050] <Glass Fibers> In a preferred embodiment, component (b21) includes glass fibers. The glass fibers may be glass fibers with a diameter difference ratio (hereinafter also simply referred to as "diameter difference ratio") of 1.5 or more, or 1.4 or less, which is the ratio of the major axis (longest straight distance of the cross section) of the cross section perpendicular to the longitudinal direction to the minor axis (longest straight distance in the direction perpendicular to the major axis) of the cross section (major axis of the cross section / minor axis of the cross section). The diameter difference ratio refers to the diameter difference ratio of the initial shape (shape before melting and kneading). The diameter difference ratio can be calculated using a scanning electron microscope and image processing software, and the arithmetic mean measured for 10 glass fibers is used. The diameter difference ratio may also be the manufacturer's value (a value published by the manufacturer in a catalog, etc.).

[0051] (Glass fibers with a diameter difference ratio of 1.5 or more) When using glass fibers with a diameter difference ratio of 1.5 or more, the diameter difference ratio may be 2.0 or more, 3.0 or more, 3.5 or more, or 3.8 or more. The upper limit of the diameter difference ratio may be 10.0 or less, 8.0 or less, or 6.0 or less. In one embodiment, the diameter difference ratio of the glass fibers may be 1.5 to 10.0, 2.0 to 9.5, 3.0 to 9.0, 3.5 to 8.0, or 3.8 to 6.0. In one embodiment, the diameter difference ratio of the glass fibers may be 4.0, and this may be the upper or lower limit of the numerical range described above.

[0052] In one embodiment, the major diameter of a cross-section perpendicular to the longitudinal direction of glass fibers with an aspect ratio of 1.5 or more may be 10 to 40 μm, or may be 20 to 30 μm. In one embodiment, the minor diameter of a cross-section perpendicular to the longitudinal direction of glass fibers with an aspect ratio of 1.5 or more may be 1 to 20 μm, or may be 3 to 10 μm. The major diameter and the minor diameter of the cross-section perpendicular to the longitudinal direction can both be calculated using a scanning electron microscope and image processing software, and are taken as the arithmetic mean value measured for 10 glass fibers. Also, the major diameter and the minor diameter of the cross-section perpendicular to the longitudinal direction can both adopt the manufacturer's values (the values publicly announced by the manufacturer in a catalog or the like).

[0053] The cross-sectional area of glass fibers with an aspect ratio of 1.5 or more is 1×10 －５ to 1×10 －３ mm ２ and may be, or may be 1×10 －４ to 5×10 －４ mm ２ The "cross-sectional area" can be a value obtained by multiplying the value obtained by dividing the major diameter by 2 and the value obtained by dividing the minor diameter by 2, and further multiplying by the pi π, when the longest straight-line distance of the cross-section of the glass fiber measured using a scanning electron microscope and image processing software is taken as the major diameter and the shortest straight-line distance is taken as the minor diameter. The cross-sectional area is taken as the arithmetic mean value measured for 10 glass fibers.

[0054] When using glass fibers with an aspect ratio of 1.5 or more as the (b21) component, commercially available products may be used as the glass fibers. As commercially available products, for example, products manufactured by Nitto Boseki Co., Ltd., such as profiled cross-section chopped strands (product name "CSG 3PA-830" (major diameter: 28 μm, minor diameter: 7 μm), product name "CSG 3PA-820" (major diameter: 28 μm, minor diameter: 7 μm), product name "CSG 3PL-962" (major diameter: 20 μm, minor diameter: 10 μm)) can be adopted.

[0055] (Glass fibers with a diameter difference ratio of 1.4 or less) When using glass fibers with a diameter difference ratio of 1.4 or less, the diameter difference ratio may be 1.0. In one embodiment, the diameter difference ratio of the glass fibers may be 1.0 to 1.4, 1.0 to 1.3, 1.0 to 1.2, or 1.0 to 1.1.

[0056] In one embodiment, the major axis of a cross-section perpendicular to the longitudinal direction of glass fibers with a diameter ratio of 1.4 or less may be 1 to 25 μm or 3 to 20 μm. In one embodiment, the minor axis of a cross-section perpendicular to the longitudinal direction of glass fibers with a diameter ratio of 1.4 or less may be 1 to 25 μm or 3 to 20 μm. Both the major and minor axes of the cross-section perpendicular to the longitudinal direction can be calculated using a scanning electron microscope and image processing software, and the arithmetic mean measured for 10 glass fibers is used. Alternatively, the manufacturer's values ​​(values ​​published by the manufacturer in catalogs, etc.) can also be used for both the major and minor axes of the cross-section perpendicular to the longitudinal direction.

[0057] When the ratio of different diameters is 1.0, the lengths of the major and minor diameters are the same, and the major or minor diameter becomes the fiber diameter. In one embodiment, when the ratio of different diameters is 1.0, the average fiber diameter is preferably 9 to 17 μm, and more preferably 9 to 15 μm, from the viewpoint of further improving mechanical properties. The average fiber diameter when the ratio of different diameters is 1.0 can be calculated using a scanning electron microscope and image processing software, and is the arithmetic mean of the longest straight-line distance of the cross-section perpendicular to the longitudinal direction, measured for 50 glass fibers. Alternatively, the average fiber diameter can be the manufacturer's value (a value published by the manufacturer in their catalog, etc.).

[0058] The cross-sectional area of ​​glass fibers with a diameter ratio of 1.4 or less is 1 × 10⁻⁶. －５ ~1 x 10 －３ mm ２ It may also be 2 x 10 －５ ~8 x 10 －３ mm ２ That's fine.

[0059] (b21) When using glass fibers with a diameter ratio of 1.4 or less as component, commercially available glass fibers may be used. Commercially available options include, for example, chopped strands from Nippon Electric Glass Co., Ltd. (product names "ECS 03T-747N" (average fiber diameter: 17 μm), "ECS 03T-747" (average fiber diameter: 13 μm), "ECS 03T-717" (average fiber diameter: 13 μm), "ECS 03T-747H" (average fiber diameter: 10.5 μm), "ECS 03T-790DE" (average fiber diameter: 6 μm), etc.), chopped glass fibers from Fuji Fiber Glass Co., Ltd. (product name "CS 3DE-257" (average fiber diameter: 6 μm), etc.), and chopped glass fibers from Owens Corning Manufacturing Co., Ltd. (product name "CS03DE 416A" (average fiber diameter: 6 μm), etc.).

[0060] The (b21) component may include one or more selected from the above-mentioned glass with a diameter difference ratio of 1.5 or more and glass with a diameter difference ratio of 1.4 or less, and two or more types may be used in combination. Furthermore, if the (b21) component includes only glass fibers with a diameter difference ratio of 1.5 or more, or only glass fibers with a diameter difference ratio of 1.4 or less, or if glass fibers with a diameter difference ratio of 1.5 or more and glass fibers with a diameter difference ratio of 1.4 or less are used in combination, two or more types of glass fibers with a diameter difference ratio of 1.5 or more or glass fibers with a diameter difference ratio of 1.4 or less may be used in combination. "Using two or more types in combination" includes using two or more types of glass fibers with different diameter difference ratios and / or average fiber lengths. The average fiber length, average fiber diameter, and specific gravity of the glass fibers can preferably be within the ranges described above. In one embodiment, the average fiber length (cut length) of the glass fibers in the initial shape to be blended into the resin composition is preferably 1 to 5 mm, and more preferably 2 to 4 mm.

[0061] [Plate-shaped inorganic filler (b22)] The resin composition according to the first embodiment may include a plate-shaped inorganic filler (b22) (hereinafter sometimes referred to as "(b22) component") as component (b2). In this disclosure, "plate-shaped" refers to a shape in which the ratio of different diameters is greater than 4 and the aspect ratio is 1 to 500. Examples of component (b22) include glass flakes, mica, kaolin, clay, alumina (plate-shaped), etc. In one embodiment, it is preferable to use a component (b22) with an average particle diameter (volume-based cumulative 50% diameter D50) of 10 to 1000 μm, and more preferably one with an average particle diameter of 30 to 800 μm. The average particle diameter (volume-based cumulative 50% diameter D50) refers to the value measured by laser diffraction scattering.

[0062] In one embodiment, component (b22) is preferably used with a specific gravity of 2.0 to 4.0, more preferably 2.0 to 3.5, and even more preferably 2.0 to 3.3. If the specific gravity of component (b22) is within the above range, the molded product tends to be lightweight.

[0063] [Powdered or Granular Inorganic Filler (b23)] The resin composition according to the first embodiment may contain a powdered or granular inorganic filler (b23) (hereinafter sometimes referred to as "(b23) component") as component (b2). Examples of component (b23) include silica; quartz powder; glass beads; glass powder; silicates such as calcium silicate, aluminum silicate, and diatomaceous earth; metal oxides such as iron oxide, titanium oxide, zinc oxide, and alumina (granular); metal carbonates such as calcium carbonate and magnesium carbonate; metal sulfates such as calcium sulfate and barium sulfate; and others such as silicon carbide, silicon nitride, and boron nitride. These may be used individually or in combination of two or more. Of these, from the viewpoint of moldability and ease of availability, component (b23) preferably contains a metal carbonate, and more preferably contains calcium carbonate.

[0064] In one embodiment, the (b23) component is preferably one with an average particle size (D50) of 0.1 to 50 μm, and more preferably one with an average particle size (D50) of 1 to 40 μm. The average particle size (D50) refers to the value measured by laser diffraction scattering.

[0065] In one embodiment, component (b23) is preferably used with a specific gravity of 2.0 to 4.0, more preferably 2.0 to 3.5, and even more preferably 2.0 to 3.3. If the specific gravity of component (b23) is within the above range, the molded product tends to be lightweight.

[0066] In one embodiment, the specific gravities of components (b21), (b22), and (b23) incorporated into the resin composition are preferably all between 2.0 and 4.0.

[0067] <Condition (I)> The resin composition according to the first embodiment comprises the aforementioned resin (A) and the aforementioned drawdown inhibitor (B). When condition (I) is satisfied, the ratio of the drawdown inhibitor (B) to the resin (A) is 8 parts by mass or more of component (b1) and 50 parts by mass or more of component (b21) per 100 parts by mass of resin (A). Surprisingly, by including 8 parts by mass or more of component (b1) and 50 parts by mass or more of component (b21) per 100 parts by mass of resin (A), a molded article that does not draw down can be obtained even when exposed to a high-temperature atmosphere exceeding the melting point of resin (A) (for example, an atmosphere of 360°C).

[0068] In condition (I), the upper limit of component (b1) per 100 parts by mass of resin (A) is not particularly limited as long as the effects of this disclosure are achieved, but from the viewpoint of mechanical properties, 60 parts by mass or less is preferred. In one embodiment, the ratio of component (b1) per 100 parts by mass of resin (A) is preferably 8 to 60 parts by mass, more preferably 9 to 57 parts by mass, and even more preferably 10 to 56 parts by mass. In one preferred embodiment, component (b11) is included in 8 to 60 parts by mass per 100 parts by mass of resin (A).

[0069] In condition (I), the upper limit of component (b21) per 100 parts by mass of resin (A) is not particularly limited as long as the effects of this disclosure are achieved, but from the viewpoint of mechanical properties, 360 parts by mass or less is preferred. In one embodiment, the ratio of component (b21) per 100 parts by mass of resin (A) is preferably 50 to 360 parts by mass, more preferably 55 to 320 parts by mass, and even more preferably 60 to 310 parts by mass.

[0070] In condition (I), the resin (A) contains 50 parts by mass or more of component (b21) per 100 parts by mass, but may also contain inorganic fillers other than component (b21) (the aforementioned components (b22) and / or (b23)) as component (b2). In other words, an embodiment in which the resin (A) contains 50 parts by mass or more of component (b21) and also contains components (b22) and / or (b23) per 100 parts by mass is also included in condition (I).

[0071] In condition (I), when component (b21) is used in combination with component (b22) and / or component (b23), the mass ratio of component (b21) to the total amount of components (b22) and (b23) (((b22) + (b23)):(b21)) is preferably 1:1 to 1:4, and more preferably 1:1 to 1:2.

[0072] In one embodiment, the resin (A) contains 8 parts by mass or more of component (b1) and 50 parts by mass or more of component (b21) per 100 parts by mass of resin (A), and the mass ratio of component (b21) to component (b21) ((b21) / (b1)) is preferably 3 to 15, and more preferably 4 to 12. If the mass ratio of component (b21) to component (b1) is within the above range, it becomes easier to obtain molded products that do not draw down even when exposed to a high-temperature atmosphere exceeding the melting point of resin (A).

[0073] <Condition (II)> When the resin composition according to the first embodiment satisfies condition (II), it contains 8 parts by mass or more of component (b1) and 200 parts by mass or more of component (b2) per 100 parts by mass of resin (A). By containing 8 parts by mass or more of component (b1) and 200 parts by mass or more of component (b2) per 100 parts by mass of resin (A), a molded article that does not draw down can be obtained even when exposed to a high-temperature atmosphere exceeding the melting point of resin (A) (for example, an atmosphere at 360°C), just as when condition (I) is satisfied. Note that in condition (II), component (b21) may be included in component (b2). However, an embodiment containing 50 parts by mass or more of component (b21) is included in condition (I). Condition (II) is that it does not contain component (b21), or contains less than 50 parts by mass of component (b21) per 100 parts by mass of resin (A) (i.e., contains 0 or more but less than 50 parts by mass of component (b21) per 100 parts by mass of resin (A)), and contains inorganic fillers other than component (b21), preferably component (b22) and / or component (b23).

[0074] In condition (II), the upper limit of component (b1) per 100 parts by mass of resin (A) is not particularly limited as long as the effects of this disclosure are achieved, but from the viewpoint of balancing mechanical properties and drawdown resistance, 60 parts by mass or less is preferred. In one embodiment, the ratio of component (b1) per 100 parts by mass of resin (A) is preferably 8 to 60 parts by mass, more preferably 9 to 57 parts by mass, and even more preferably 10 to 56 parts by mass. In one preferred embodiment, component (b11) is included in 8 to 60 parts by mass per 100 parts by mass of resin (A).

[0075] In condition (II), the upper limit of component (b2) per 100 parts by mass of resin (A) is not particularly limited as long as the effects of this disclosure are achieved, but from the viewpoint of mechanical properties, 360 parts by mass or less is preferred. In one embodiment, the ratio of component (b2) per 100 parts by mass of resin (A) is preferably 200 to 360 parts by mass, more preferably 210 to 320 parts by mass, and even more preferably 220 to 310 parts by mass.

[0076] A preferred embodiment that satisfies condition (II) contains a total of 200 parts by mass or more of component (b2) other than component (b21) per 100 parts by mass of resin (A). A more preferred embodiment contains 200 parts by mass or more of component (b23) only per 100 parts by mass of resin (A). A still preferred embodiment contains 200 parts by mass or more of calcium carbonate per 100 parts by mass of resin (A).

[0077] In one embodiment, the resin (A) contains 8 parts by mass or more of component (b1) and 200 parts by mass or more of component (b2) per 100 parts by mass of resin (A), and the mass ratio of component (b2) to component (b1) ((b2) / (b1)) is preferably 3 to 15, and more preferably 4 to 12. If the mass ratio of component (b2) to component (b1) is within the above range, it is easier to obtain molded products that do not draw down.

[0078] <Condition (III)> If the resin composition according to the first embodiment satisfies condition (III), it contains component (b21) as component (b2), and further contains 8 parts by mass or more of component (b1), 39 parts by mass or more but less than 50 parts by mass of component (b21), and 115 parts by mass or more but less than 200 parts by mass of component (b2) per 100 parts by mass of resin (A). By including components (b1), (b2), and (b21) in the above proportions per 100 parts by mass of resin (A), a molded article that does not draw down can be obtained even when exposed to a high-temperature atmosphere exceeding the melting point of resin (A) (for example, an atmosphere of 360°C), just as when conditions (I) and (II) are satisfied.

[0079] In condition (III), the upper limit of component (b1) per 100 parts by mass of resin (A) is not particularly limited as long as the effects of this disclosure are achieved, but from the viewpoint of mechanical properties, 60 parts by mass or less is preferred. In one embodiment, the ratio of component (b1) per 100 parts by mass of resin (A) is preferably 8 to 60 parts by mass, more preferably 9 to 57 parts by mass, and even more preferably 10 to 56 parts by mass. In one preferred embodiment, component (b11) is included in 8 to 60 parts by mass per 100 parts by mass of resin (A).

[0080] In condition (III), the ratio of component (b21) to 100 parts by mass of resin (A) is 39 parts by mass or more and less than 50 parts by mass. In one embodiment, the ratio of component (b21) to 100 parts by mass of resin (A) is preferably 39 to 49 parts by mass, more preferably 39 to 48 parts by mass, and even more preferably 39 to 46 parts by mass.

[0081] In condition (III), the ratio of component (b2) to 100 parts by mass of resin (A) is 115 parts by mass or more and less than 200 parts by mass. In one embodiment, the ratio of component (b2) to 100 parts by mass of resin (A) is preferably 115 to 190 parts by mass, more preferably 115 to 180 parts by mass, and even more preferably 115 to 170 parts by mass.

[0082] A preferred embodiment that satisfies condition (III) includes, per 100 parts by mass of resin (A), 39 parts by mass or more and less than 50 parts by mass of component (b21) and 65 parts by mass or more and less than 161 parts by mass of component (b23). A more preferred embodiment includes, per 100 parts by mass of resin (A), 39 parts by mass or more and less than 50 parts by mass of glass fiber and 65 parts by mass or more and less than 161 parts by mass of calcium carbonate.

[0083] In condition (III), when component (b21) is used in combination with component (b22) and / or component (b23), the mass ratio of component (b21) to the total amount of components (b22) and (b23) (((b22) + (b23)):(b21)) is preferably 4:1 to 1.3:1, and more preferably 2:1 to 1.3:1.

[0084] In one embodiment of condition (III), the resin (A) contains 8 parts by mass or more of component (b1) and 39 parts by mass or more but less than 50 parts by mass of component (b21) per 100 parts by mass of resin (A), and the mass ratio of component (b21) to component (b1) ((b21) / (b1)) is preferably 1 to 6, and more preferably 1.2 to 5. If the mass ratio of component (b21) to component (b1) is within the above range, it is easier to obtain molded products that do not draw down.

[0085] In all of conditions (I) to (III), the ratio of the drawdown inhibitor (B) to the total mass of the resin composition is preferably 35 to 80% by mass, and more preferably 36 to 79% by mass. The ratio of the resin (A) to the total mass of the resin composition is preferably 20 to 65% by mass, and more preferably 21 to 64% by mass. Even in the resin composition according to the first embodiment, where the proportion of resin (A) is relatively high, the drawdown of the resulting molded article is easily suppressed by combining the resin (A) with the drawdown inhibitor (B), which contains an epoxy group and / or glycidyl group-containing polymer (b1) and an inorganic filler (b2), in a fixed proportion.

[0086] <Other Components (C)> The resin composition according to the first embodiment may contain any components other than the resin (A) and the drawdown inhibitor (B) (other components (C)). Examples of other components include thermosetting resins other than component (b2) (other resins), organic fillers, lubricants, nucleating agents, flame retardants, flame retardant aids, antioxidants, metal deactivators, UV absorbers, stabilizers, plasticizers, pigments, dyes, colorants, antistatic agents, foaming agents, and other additives. The other components may be used individually or in combination of two or more.

[0087] In one embodiment, as resin (A), the melt viscosity of the resin composition containing resin (a1) (measurement temperature: 310°C, shear rate: 1000 sec) －１ From the viewpoint of moldability, the viscosity of the resin (A) is preferably 50 to 700 Pa·s, more preferably 80 to 600 Pa·s, and even more preferably 100 to 500 Pa·s. Furthermore, as resin (A), the melt viscosity of the resin composition containing resin (a2) is measured at a temperature of 260°C and a shear rate of 1000 sec. －１ From the viewpoint of moldability, a pressure of 50 to 700 Pa·s is preferred, 80 to 600 Pa·s is more preferred, and 100 to 500 Pa·s is even more preferred.

[0088] As described above, the invention according to the first embodiment has found that by blending a specific amount of epoxy group and / or glycidyl group-containing polymer (b1) and inorganic filler (b2) into resin (A), these components (b1) and (b2) function as drawdown inhibitors. The exact reason why drawdown is suppressed by the combination of components (b1) and (b2) is unknown, but the inventors of this application consider that when exposed to a high-temperature atmosphere exceeding the melting point of resin (A), a reaction occurs between component (b1) and resin (A), resulting in abnormal viscosity increase. It is also possible that, under such a high-temperature atmosphere, the surfaces of component (b1) and component (b2) become affinity, preventing the molten resin (A) from melting down. No resin composition containing components (b1) and (b2) as drawdown inhibitors for thermoplastic resin (A) has been previously known, and the resin composition according to the first embodiment is a novel composition. Furthermore, the resin composition according to the first embodiment can provide molded articles that suppress drawdown under high-temperature conditions, while also having good moldability.

[0089] <Method for producing a resin composition> The method for producing a resin composition according to the first embodiment includes melt-kneading a resin (A) and a drawdown inhibitor (B), more specifically, melt-kneading 100 parts by mass of resin (A), 8 parts by mass or more of component (b1), and 50 parts by mass or more of component (b21) ((I)), melt-kneading 100 parts by mass of resin (A), 8 parts by mass or more of component (b1), and 200 parts by mass or more of component (b2) ((II)), or blending 100 parts by mass of resin (A), 8 parts by mass or more of component (b1), and 39 parts by mass or more but less than 50 parts by mass of component (b21), and melt-kneading them so that the total amount of component (b2) is 115 parts by mass or more but less than 200 parts by mass ((III)).

[0090] Melt mixing can generally be carried out using equipment and methods commonly used for preparing resin compositions. Typically, the necessary components are mixed and then melt-mixed using a single-screw or twin-screw extruder. The mixture can then be extruded to form molding pellets.

[0091] [Molded Articles] A second embodiment of this disclosure relates to molded articles of a resin composition according to the first embodiment. A molded article according to the second embodiment has drawdown resistance, meaning it does not draw down when exposed to a high-temperature atmosphere exceeding the melting point of the resin (A). In one embodiment, it is preferable that the molded article has drawdown resistance, meaning it does not draw down when exposed to an atmosphere of 360°C. In this disclosure, "drawdown" refers to the phenomenon in which a molten molded article melts down in the direction of gravity.

[0092] In one embodiment, it is preferable that the molded product according to the second embodiment does not draw down when exposed to a 700°C atmosphere for 15 minutes. The draw-down resistance in a 700°C atmosphere can be evaluated under the following conditions. <Evaluation of draw-down resistance in a 700°C atmosphere> The test piece (40 mm × 15 mm × 3 mm thick) is fixed in the heating furnace with both ends gripped and the piece fixed at a height of 40 mm from the hearth. Then, the temperature of the heating furnace is set to 700°C, and the piece is left in the 700°C atmosphere for 15 minutes. A test piece that does not melt down to the hearth, or a test piece that does not detach from one or both gripping parts and whose molten form does not hang down to the hearth, is evaluated as "not drawing down when exposed to 700°C for 15 minutes."

[0093] Figure 1 shows the jig used for evaluating drawdown resistance and a photograph of the test specimen before testing. Figure 2 shows a photograph of the test specimen after the drawdown resistance evaluation of Example 1, and Figure 3 shows a photograph of the test specimen after the drawdown resistance evaluation of Comparative Example 1. As shown in Figure 3, molded articles obtained from resin compositions that do not satisfy the above conditions (I), (II), or (III) show drawdown as the test specimen melts down to the furnace bed. On the other hand, as shown in Figure 2, the molded article of the resin composition according to the first embodiment (the molded article of Example 1) shows swelling in part of the test specimen, but no melting of the resin occurs and no drawdown occurs.

[0094] In one embodiment, the amount of deformation of the test specimen after heating in accordance with the above-mentioned drawdown resistance evaluation (the distance the test specimen hangs down (mm) relative to a height of 40 mm) is preferably in the range of 0 to 25 mm.

[0095] [Method for Manufacturing Molded Articles] A molded article according to the second embodiment can be obtained by molding the resin composition according to the first embodiment. More specifically, this molding includes molding the resin composition according to the first embodiment using generally known molding methods for thermoplastic resins, such as injection molding, extrusion molding, vacuum molding, and compression molding.

[0096] <Applications> As described above, the molded article according to the second embodiment does not draw down when exposed to a high-temperature atmosphere. Such molded articles can be suitably used for equipment equipped with batteries, and especially for equipment in fields where resistance to drawdown is required. In one embodiment, it is preferable that the molded article be used in an environment in which it may be exposed to an atmosphere of 360°C or higher.

[0097] (Devices equipped with batteries) Examples of devices equipped with batteries include devices equipped with the above-mentioned lead-acid batteries, nickel-metal hydride batteries, NAS batteries, or lithium-ion batteries. Furthermore, it is preferable that such devices are used for at least one application selected from automotive, next-generation mobility, infrastructure, mobile, and household use. Here, "automotive devices" include devices used in (or installed in) existing vehicles (e.g., automobiles (electric vehicles, hybrid vehicles, etc.) and railway vehicles, etc.). "Next-generation mobility devices" include devices used in advanced means of transportation that utilize cutting-edge technologies such as autonomous driving. "Infrastructure devices" include devices used in social infrastructure and industrial fields. "Mobile devices" include electronic devices such as smartphones and personal computers. "Household devices" include household storage batteries, etc.

[0098] Preferred applications for the molded product according to the second embodiment include, for example, power supply components, high-voltage components, refractory containers, or refractory components.

[0099] Power supply components refer to components such as regulator components and DC / DC converter components, which connect input power supply wiring and output power supply wiring, as well as components such as inductors and ferrite bead components, which do not change their electrical meaning between the input connection network and the output connection network.

[0100] High-voltage components refer to all components through which a high voltage of 300V or more, preferably 600V or more, flows. Examples of high-voltage components include various electrical and electronic components through which the above-mentioned high voltage flows, such as transistors, thyristors, inverters, converters, connectors, switches, and electromagnetic contactors; automotive components such as those related to HEV / EV drives and power steering; new energy-related components such as solar cells and wind power; components for electric railways; components for various home appliances, as well as their surrounding circuit boards, housings, cases, and module components.

[0101] Of these, the molded article according to the second embodiment is preferably for use in equipment equipped with a lithium-ion battery. Furthermore, such equipment is particularly preferably for automotive and / or next-generation mobility applications. In equipment equipped with a lithium-ion battery used in such applications, the molded article according to the second embodiment is particularly preferably used in related components, including at least one component selected from housings such as upper covers, insulating components such as busbars, and heat-shielding and insulating components such as busbar covers and module covers.

[0102] [Method for improving the drawdown resistance of molded articles] A third embodiment of the present disclosure relates to a method for improving the drawdown resistance of molded articles. The method according to the third embodiment includes blending a drawdown inhibitor (B) containing an epoxy group and / or glycidyl group-containing polymer (b1) and an inorganic filler (b2) with 100 parts by mass of the thermoplastic resin (A) constituting the molded article, wherein the blending is as follows: (I) Selecting a fibrous inorganic filler (b21) as the inorganic filler (b2), and blending 8 parts by mass or more of the epoxy group and / or glycidyl group-containing polymer (b1) and 50 parts by mass or more of the fibrous inorganic filler (b21) with 100 parts by mass of the thermoplastic resin (A); (II) Blending 8 parts by mass or more of the epoxy group and / or glycidyl group-containing polymer (b1) and 200 parts by mass or more of the inorganic filler (b2) with 100 parts by mass of the thermoplastic resin (A); or (III) Selecting a fibrous inorganic filler (b21) as the inorganic filler (b2), This method involves blending 8 parts by mass or more of an epoxy group and / or glycidyl group-containing polymer (b1) and 39 parts by mass or more but less than 50 parts by mass of a fibrous inorganic filler (b21) with 100 parts by mass of a thermoplastic resin (A), and further blending inorganic filler (b2) such that the total amount of inorganic filler (b2) is 115 parts by mass or more but less than 200 parts by mass.

[0103] In the third embodiment, "improving the drawdown resistance of the molded product" may include the molded product not drawing down when exposed to a 360°C atmosphere. It may also include the molded product not drawing down when exposed to a 700°C atmosphere for 15 minutes. The "drawdown resistance evaluation" described in the second embodiment can be applied to evaluate the drawdown resistance.

[0104] The shape and application of the molded product are not particularly limited, but preferably examples include the equipment and parts described in the section on applications of the molded product according to the second embodiment described above.

[0105] Other embodiments of the present disclosure include the use or method of using an epoxy group and / or glycidyl group-containing polymer (b1) and an inorganic filler (b2) as a drawdown inhibitor (B) for a molded article containing a thermoplastic resin (A). The above-mentioned use or method of use is as follows: (I) Select a fibrous inorganic filler (b21) as the inorganic filler (b2), and blend 8 parts by mass or more of epoxy group and / or glycidyl group-containing polymer (b1) and 50 parts by mass or more of fibrous inorganic filler (b21) with 100 parts by mass of thermoplastic resin (A); (II) Blend 8 parts by mass or more of epoxy group and / or glycidyl group-containing polymer (b1) and 200 parts by mass or more of inorganic filler (b2) with 100 parts by mass of thermoplastic resin (A); or (III) Select a fibrous inorganic filler (b21) as the inorganic filler (b2), and blend 8 parts by mass or more of epoxy group and / or glycidyl group-containing polymer (b1) and 50 parts by mass or more of fibrous inorganic filler (b2) with 100 parts by mass of thermoplastic resin (A). This includes blending 8 parts by mass or more of an epoxy group and / or glycidyl group-containing polymer (b1) and 39 parts by mass or more but less than 50 parts by mass of a fibrous inorganic filler (b21), and further blending inorganic filler (b2) such that the total amount of inorganic filler (b2) is 115 parts by mass or more but less than 200 parts by mass.

[0106] A non-limiting list of exemplary embodiments and combinations of exemplary embodiments of the present disclosure is given below. [1] A drawdown inhibitor (B) comprising a thermoplastic resin (A), an epoxy group and / or glycidyl group-containing polymer (b1), and an inorganic filler (b2), the following (I): (I) comprising a fibrous inorganic filler (b21) as the inorganic filler (b2), comprising 8 parts by mass or more of the polymer (b1) and 50 parts by mass or more of the fibrous inorganic filler (b21) per 100 parts by mass of the thermoplastic resin (A), the following (II): (II) comprising 8 parts by mass or more of the polymer (b1) and 200 parts by mass or more of the inorganic filler (b2) per 100 parts by mass of the thermoplastic resin (A), A resin composition comprising 8 parts by mass or more of the polymer (b1), 39 parts by mass or more but less than 50 parts by mass of the fibrous inorganic filler (b21), and 115 parts by mass or more but less than 200 parts by mass of the inorganic filler (b2). [2] The resin composition according to [1], wherein the polymer (b1) comprises one or more selected from epoxy group and / or glycidyl group-containing olefin copolymers (b11) and epoxy resins (b12). [3] The resin composition according to [2], wherein the olefin copolymer (b11) comprises an olefin copolymer containing a structural unit derived from an α-olefin having two or more carbon atoms and a structural unit derived from a glycidyl ester of an α,β-unsaturated acid. [4] The resin composition according to any one of [1] to [3], wherein the thermoplastic resin (A) comprises a polyarylene sulfide resin (a1) or a polybutylene terephthalate resin (a2). [5] The resin composition according to any one of [1] to [4], wherein the inorganic filler (b2) comprises one or more selected from the fibrous inorganic filler (b21), plate-like inorganic filler (b22), and powder-like inorganic filler (b23). [6] The resin composition according to [5], wherein the specific gravity of the fibrous inorganic filler (b21), plate-like inorganic filler (b22), and powder-like inorganic filler (b23) is 2.0 to 4.0.[7] The resin composition according to any one of [1] to [6], wherein the fibrous inorganic filler (b21) contains glass fibers. [8] The resin composition according to any one of [5] to [7], wherein the granular inorganic filler (b23) contains calcium carbonate. [9] The resin composition according to any one of [1] to [8], wherein the total amount of epoxy groups and glycidyl groups in the resin composition is 10 μmol / g or more.

[10] A molded article of the resin composition according to any one of [1] to [9].

[11] The molded article according to

[10] , which has drawdown resistance and does not draw down when exposed to an atmosphere of 360°C.

[12] The molded article according to

[10] or

[11] , which does not draw down when exposed to an atmosphere of 700°C for 15 minutes.

[13] The molded article according to any one of

[10] to

[12] , which is for use in equipment equipped with a battery.

[14] The molded article according to any one of

[10] to

[13] , which is for use in equipment equipped with a lithium-ion battery.

[15] The molded article according to

[14] , wherein the device is used for at least one application selected from automotive, next-generation mobility, infrastructure, mobile, and household.

[16] The molded article according to any one of

[10] to

[15] , wherein the device is used for power supply components, high-voltage components, refractory containers, or refractory components.

[17] The molded article according to any one of

[10] to

[16] , wherein the molded article is used in an environment in which it may be exposed to an atmosphere of 360°C or higher.

[0107] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following description.

[0108] [Materials] The materials used in the examples and comparative examples are as follows: <Resin (A)> ・Resin (a1): Polyphenylene sulfide (PPS) resin, manufactured by Kureha Corporation, Fortron® KPS, melt viscosity: 20 Pa·s (shear rate: 1200 sec －１ (310°C) (Measurement of melt viscosity of PPS resin) The melt viscosity of the above PPS resin was measured as follows: Using a capillary graph manufactured by Toyo Seiki Seisakusho Co., Ltd., a flat die of 1 mmφ × 20 mmL was used as the capillary, with a barrel temperature of 310°C and a shear rate of 1200 sec. －１The melt viscosity was measured. • Resin (a2): Polybutylene terephthalate (PBT) resin, manufactured by Polyplastics Co., Ltd., (Intrinsic viscosity: 0.69 dL / g) <Drawdown inhibitor (B)> • (b11-1): Ethylene (70%)-glycidyl methacrylate (3%)-methacrylate (27%) copolymer, manufactured by Sumitomo Chemical Co., Ltd., Bondfast 7L, epoxy group weight: 213 μmol / g • (b11-2): Ethylene (67%)-glycidyl methacrylate (6%)-methacrylate (27%) copolymer, manufactured by Sumitomo Chemical Co., Ltd., Bondfast 7M, epoxy group weight: 425 μmol / g • (b12): Epoxy resin, manufactured by Mitsubishi Chemical Corporation, jER1004K, epoxy group weight: 1081 μmol / g • (b21): Glass fiber, manufactured by Nippon Electric Glass Co., Ltd., chopped strand ECS03T-747H, average fiber diameter: 10.5 μm, average fiber length: 3 mm, specific gravity: 2.6 • (b22): Calcium carbonate, manufactured by Toyo Fine Chemical Co., Ltd., Whiteon® P-30, average particle size (D50): 5 μm, specific gravity: 2.7

[0109] [Examples 1-12 and Comparative Examples 1-9] Using the above materials, each component was dry-blended according to the composition and content ratio shown in Table 1. Then, the mixture was fed into a twin-screw extruder with a cylinder temperature of 290°C (component (b21) (glass fiber) was added separately from the side feed section of the extruder) and melt-kneaded to obtain resin composition pellets. Next, the obtained pellets were injection-molded using a molding machine (manufactured by FANUC Corporation, product name "α-S100iA") at a cylinder temperature of 320°C, a mold temperature of 150°C, and an injection speed of 40 mm / sec to obtain molded products (80 mm × 80 mm × 3 mm t). The drawdown resistance of the obtained molded products was evaluated under the following conditions in a 700°C atmosphere. The results are shown in Tables 1-2.

[0110] [Example 13] Using the above materials, each component was dry-blended according to the composition and content ratio shown in Table 1. Then, it was put into a twin-screw extruder with a cylinder temperature of 260°C in the kneading section (component (b21) (glass fiber) was added separately from the side feed section of the extruder) and melt-kneaded to obtain resin composition pellets. Next, the obtained pellets were injection-molded using a molding machine (manufactured by FANUC Corporation, product name "α-S100iA") at a cylinder temperature of 260°C, a mold temperature of 80°C, and an injection speed of 40 mm / sec to obtain a molded product (80 mm × 80 mm × 3 mmt). The drawdown resistance of the obtained molded product was evaluated under the following conditions in a 700°C atmosphere. The results are shown in Table 1.

[0111] <Measurement of Melt Viscosity of Resin Compositions> Using a capillary graph manufactured by Toyo Seiki Seisakusho Co., Ltd., a flat die of 1 mmφ × 20 mmL was used as the capillary. For Examples 1 to 12 and Comparative Examples 1 to 9, the barrel temperature was 310°C and the shear rate was 1000 sec. －１ The melt viscosity was measured. In addition, in Example 13, the barrel temperature was 260°C and the shear rate was 1000 sec. －１ The melt viscosity was measured. The results are shown in Tables 1 and 2.

[0112] <Evaluation of drawdown resistance under a 700°C atmosphere> Test specimens (40 mm x 15 mm x 3 mm thick) were prepared by cutting out the molded product from each example at a position 20 mm from the side parallel to the resin flow direction and on the gate side. Both ends of the test specimen were gripped with iron fasteners and fixed at a height of 40 mm from the hearth, and placed in an electric furnace (manufactured by Yamato Scientific Co., Ltd., product name "Muffle Furnance FP312"). The electric furnace was then heated to 700°C, and after reaching 700°C, it was left in that temperature atmosphere for 15 minutes. The condition of the test specimen in the electric furnace was visually checked, and the amount of deformation of the test specimen (the distance the molded product sagged (mm) relative to the height of 40 mm) was measured. The amount of deformation of samples in which the molded product drew down (samples in which the molten test specimen melted down to the hearth) was evaluated as 40 mm.

[0113]

[0114]

[0115] As shown in Tables 1-2, the molded articles of Examples 1-13 (molded articles of the resin composition according to the first embodiment) did not experience drawdown even when exposed to a high-temperature atmosphere exceeding the melting point of resin (A). On the other hand, the molded articles of Comparative Examples 1, 3, 5-7, which did not contain component (b1) as the drawdown inhibitor (B), Comparative Example 2, which contained less than 50 parts by mass of component (b21), Comparative Examples 4 and 9, which contained less than 200 parts by mass of component (b2), and Comparative Example 8, which contained less than 8 parts by mass of component (b1), all experienced drawdown when exposed to a high-temperature atmosphere exceeding their melting point. From these results, it was confirmed that molded articles with drawdown resistance can be obtained from the resin composition according to the first embodiment. Furthermore, it was confirmed that the molded articles according to the second embodiment also possess drawdown resistance.

Claims

1. A drawdown inhibitor (B) comprising a thermoplastic resin (A), an epoxy group and / or glycidyl group-containing polymer (b1), and an inorganic filler (b2), wherein (I) (I) the inorganic filler (b2) is a fibrous inorganic filler (b21), and the amount is 8 parts by mass or more of the polymer (b1) and 50 parts by mass or more of the fibrous inorganic filler (b21) per 100 parts by mass of the thermoplastic resin (A), (II) (II) the amount is 8 parts by mass or more of the polymer (b1) and 200 parts by mass or more of the inorganic filler (b2) per 100 parts by mass of the thermoplastic resin (A), A resin composition comprising 8 parts by mass or more of the polymer (b1), 39 parts by mass or more but less than 50 parts by mass of the fibrous inorganic filler (b21), and 115 parts by mass or more but less than 200 parts by mass of the inorganic filler (b2).

2. The resin composition according to claim 1, wherein the polymer (b1) comprises one or more selected from epoxy group and / or glycidyl group-containing olefin copolymers (b11) and epoxy resins (b12).

3. The resin composition according to claim 2, wherein the olefin copolymer (b11) contains a structural unit derived from an α-olefin having two or more carbon atoms and a structural unit derived from a glycidyl ester of an α,β-unsaturated acid.

4. The resin composition according to claim 1 or 2, wherein the thermoplastic resin (A) comprises a polyarylene sulfide resin (a1) or a polybutylene terephthalate resin (a2).

5. The resin composition according to claim 1 or 2, wherein the inorganic filler (b2) comprises one or more selected from the fibrous inorganic filler (b21), the plate-like inorganic filler (b22), and the powder-like inorganic filler (b23).

6. The resin composition according to claim 5, wherein the specific gravity of the fibrous inorganic filler (b21), the plate-like inorganic filler (b22), and the powder-like inorganic filler (b23) is all 2.0 to 4.

0.

7. The resin composition according to claim 1 or 2, wherein the fibrous inorganic filler (b21) contains glass fibers.

8. The resin composition according to claim 5, wherein the granular inorganic filler (b23) contains calcium carbonate.

9. The resin composition according to claim 1 or 2, wherein the total amount of epoxy groups and glycidyl groups in the resin composition is 10 μmol / g or more.

10. A molded article of the resin composition according to claim 1 or 2.

11. The molded article according to claim 10, which does not draw down when exposed to a 360°C atmosphere and has draw-down resistance.

12. The molded article according to claim 10, which does not draw down when exposed to a 700°C atmosphere for 15 minutes.

13. The molded article according to claim 10, which is for use in a device equipped with a battery.

14. The molded article according to claim 10, for use in equipment equipped with a lithium-ion battery.

15. The molded article according to claim 14, wherein the device is used for at least one application selected from in-vehicle, next-generation mobility, infrastructure, mobile, and household.

16. The molded article according to claim 10, which is for use with power supply components, high-voltage components, refractory containers, or refractory components.

17. The molded article according to claim 10, wherein the molded article is used in an environment in which it may be exposed to an atmosphere of 360°C or higher.

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