Resin composition, pellets, and molded article

Abstract

To provide a resin composition, and pellets capable of providing a molded article excellent in tracking resistance while maintaining various physical properties, and a molded article.SOLUTION: There is provided a resin composition comprising: 20 to 40 pts.mass of talc, 10 to 30 pts.mass of a block copolymer, 15 to 40 pts.mass of a flame retardant, and 5 to 40 pts.mass of calcium carbonate based on 100 pts.mass in total of 50 to 100 pts.mass of a polyphenylene ether polymer and 50 to 0 pts.mass of a polystyrene polymer, wherein the talc contains 2.5 to 10 mass% of calcium and 50 to 60 mass% of silica in terms of oxides based on fluorescent X-ray analysis, and a melt mass flow rate of the block copolymer measured in accordance with JIS K7210 is 3 g / 10 minutes or less under measuring conditions of a temperature of 230°C and a load of 2.16 kg.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a resin composition, a pellet, and a molded article, and in particular to a resin composition containing a polyphenylene ether resin as a main component. [Background technology]

[0002] Polyphenylene ether resin (PPE) is a resin that has excellent properties such as heat resistance, flame retardancy, electrical properties, and dimensional stability, as well as low specific gravity and hydrolysis resistance. In addition, polyphenylene ether resin can be blended with various resins such as styrene resins to improve its moldability and impact resistance.

[0003] Such a resin composition containing a polyphenylene ether resin (polyphenylene ether resin composition) has been widely used as a material for various applications such as electric parts, electronic device parts, and vehicle parts. The polyphenylene ether resin composition is required to have various properties depending on the application. For example, when the polyphenylene ether resin composition is used as a material for a protective housing for protecting a battery unit including a battery pack or the like, the polyphenylene ether resin composition is required to have high tracking resistance in addition to flame retardancy and impact resistance required for a protective housing for the battery unit.

[0004] For example, Patent Document 1 discloses a composition that contains 45 to 65% by weight of PPE, 10 to 30% by weight of a polyalkenyl aromatic resin (styrene resin), 1 to 8% by weight of tricalcium phosphate, 3 to 15% by weight of an organic phosphate ester flame retardant, 5 to 10% by weight of titanium oxide, and 3 to 15% by weight of a reinforcing filler, and that exhibits a CTI of 350V or more according to the IEC 60112 standard. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2009 / 040751 Summary of the Invention [Problem to be solved by the invention]

[0006] The above-mentioned Patent Document 1 shows that the tracking resistance is high, but it is only about 400 V, and even higher tracking resistance is required. Even if the tracking resistance is high, if other physical properties are poor, the range of application as a resin composition is limited. The present invention aims to solve the above problems, and to provide a resin composition, pellets, and molded articles that can provide molded articles with excellent tracking resistance while maintaining various physical properties. [Means for solving the problem]

[0007] In view of the above problems, the present inventors have conducted studies and have found that the above problems can be solved by using a talc containing a polyphenylene ether resin, and optionally a styrene resin, talc, a block copolymer, and a flame retardant, the talc having a high calcium content. Specifically, the above problems were solved by the following means. <1> For a total of 100 parts by mass of 50 to 100 parts by mass of polyphenylene ether resin and 50 to 0 parts by mass of polystyrene resin, 20 to 40 parts by mass of talc; 10 to 30 parts by mass of a block copolymer; 15 to 40 parts by mass of a flame retardant; 5 to 40 parts by mass of calcium carbonate, The talc contains, based on an X-ray fluorescence analysis, 2.5 to 10 mass % of calcium and 50 to 60 mass % of silicon calculated as oxides, The block copolymer has a melt mass flow rate, as measured in accordance with JIS K7210, of 3 g / 10 min or less under measurement conditions of a temperature of 230° C. and a load of 2.16 kg. <2> The median diameter of the talc (D 50) is 10 to 25 μm; <1> The resin composition described above. <3> The resin composition contains 80 to 100 parts by mass of the polyphenylene ether resin per 100 parts by mass of the total of the polyphenylene ether resin and the polystyrene resin. <1> or <2> The resin composition according to claim 1. <4> The talc has a chlorine content of less than 0.01% by mass based on X-ray fluorescence analysis. <1> ~ <3> 10. The resin composition according to claim 9 . <5> The talc has an aluminum content of 0.1 to 5 mass% calculated as an oxide based on a fluorescent X-ray analysis. <1> ~ <4> 10. The resin composition according to claim 9 . <6> The block copolymer comprises a vinyl aromatic compound block and a conjugated diene compound block. <1> ~ <5> 10. The resin composition according to claim 9 . <7> The flame retardant includes a phosphorus-based flame retardant. <1> ~ <6> 10. The resin composition according to claim 9 . <8> Further, the stabilizer may contain a phosphorus-based stabilizer and / or a phenol-based stabilizer. <1> ~ <7> 10. The resin composition according to claim 9 . <9> The resin composition is molded into a test piece of 100 mm × 150 mm × 3.2 mm, and the CTI value measured by a measurement method in accordance with IEC 60112 is 500 V or more. <1> ~ <8> 10. The resin composition according to claim 9 . <10> The median diameter of the talc (D 50 ) is 10 to 25 μm, the resin composition contains 80 to 100 parts by mass of a polyphenylene ether-based resin per 100 parts by mass of a total of a polyphenylene ether-based resin and a polystyrene-based resin, and the amount of chlorine in the talc based on a fluorescent X-ray analysis is less than 0.01% by mass; The talc has an aluminum content of 0.1 to 5 mass% calculated as an oxide based on a fluorescent X-ray analysis, the block copolymer comprises a vinyl aromatic compound block and a conjugated diene compound block, The flame retardant includes a phosphorus-based flame retardant, Further, it contains a phosphorus-based stabilizer and / or a phenol-based stabilizer, The resin composition is molded into a test piece of 100 mm × 150 mm × 3.2 mm, and the CTI value measured by a measurement method in accordance with IEC 60112 is 500 V or more. <1> ~ <9> 10. The resin composition according to claim 9 . <11> <1> ~ <10> 2. A pellet of the resin composition according to claim 1. <12> <1> ~ <10> 2. A molded article formed from the resin composition according to claim 1. <13> <11> A molded article formed from the pellets according to claim 1. Effect of the Invention

[0008] According to the present invention, it is possible to provide a resin composition, pellets, and molded articles that can provide molded articles having excellent tracking resistance while maintaining various physical properties. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention (hereinafter, simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to the present embodiment. In this specification, the use of "to" means that the numerical values ​​before and after it are included as the lower limit and upper limit. In this specification, various physical properties and characteristic values ​​are those at 23° C. unless otherwise specified. Examples of the substituent in this specification are preferably a halogen atom, a cyano group, a nitro group, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic group, a heterocyclic oxy group, an alkenyl group, an alkylsulfanyl group, an arylsulfanyl group, an acyl group or an amino group, more preferably a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an alkenyl group or an acyl group, even more preferably an alkyl group, an aryl group, an aryloxy group or an alkenyl group, and even more preferably an alkyl group. The formula weight of these substituents is preferably 15 or more, and is preferably 200 or less. For example, the formula weight is 15 for a methyl group (-CH3). These substituents may further have a substituent, but it is preferable that they do not have a substituent. If the measurement methods, etc. described in the standards shown in this specification vary from year to year, they will be based on the standards as of January 1, 2023, unless otherwise stated.

[0010] The resin composition of the present embodiment is characterized in that, relative to a total of 100 parts by mass of 50 to 100 parts by mass of a polyphenylene ether resin and 50 to 0 parts by mass of a polystyrene resin, the composition contains 20 to 40 parts by mass of talc, 10 to 30 parts by mass of a block copolymer, 15 to 40 parts by mass of a flame retardant, and 5 to 40 parts by mass of calcium carbonate, the talc contains 2.5 to 10 mass% of calcium and 50 to 60 mass% of silicon in terms of oxide based on fluorescent X-ray analysis, and the melt mass flow rate of the block copolymer measured in accordance with JIS K7210 is 3 g / 10 min or less under measurement conditions of a temperature of 230° C. and a load of 2.16 kg. By adopting such a constitution, a resin composition capable of providing a molded product excellent in tracking resistance while maintaining various physical properties can be obtained. Talc is usually mainly composed of SiO2 and MgO, but in this embodiment, it is presumed that the tracking resistance can be improved by using talc containing calcium and having a low SiO2 content. The tracking resistance can be improved by blending calcium carbonate into the resin component, but if the calcium content in the resin component increases, other physical properties tend to deteriorate. In this embodiment, it is presumed that the tracking resistance can be increased without deteriorating the physical properties by using talc with a high calcium content.

[0011] <Polyphenylene ether resin> The resin composition of the present embodiment contains a polyphenylene ether resin. The polyphenylene ether resin is preferably a polymer having a structural unit represented by formula (1) in the main chain. The polyphenylene ether resin may be a homopolymer or a copolymer.

[0012] [ka]

[0013] In formula (1), two R a each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an aminoalkyl group, an alkoxy group, or an aryloxy group. a cannot both be hydrogen atoms. b each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkoxy group, or an aryloxy group. Furthermore, each of the above groups may be substituted with a substituent (for example, a halogen atom), but is preferably unsubstituted.

[0014] R a and R bis preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-amyl group, an isoamyl group, a 2-methylbutyl group, a 2,3-dimethylbutyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 4-methylpentyl group, a heptyl group, an isopropyl group, a sec-butyl group, and a 1-ethylpropyl group. a R is more preferably a methyl group or a phenyl group, and even more preferably a methyl group. b is particularly preferably a hydrogen atom.

[0015] Suitable examples of homopolymers of polyphenylene ether resins include 2,6-dialkylphenylene ether polymers, etc. Examples of the 2,6-dialkylphenylene ether polymers include poly(2,6-dimethyl-1,4-phenylene ether), poly(2,6-diethyl-1,4-phenylene ether), poly(2,6-dipropyl-1,4-phenylene ether), poly(2-ethyl-6-methyl-1,4-phenylene ether), poly(2-methyl-6-propyl-1,4-phenylene ether), etc.

[0016] Suitable examples of the copolymer of polyphenylene ether resin include 2,6-dialkylphenol / 2,3,6-trialkylphenol copolymer, graft copolymer obtained by graft polymerizing styrene to poly(2,6-dimethyl-1,4-phenylene ether), graft copolymer obtained by graft polymerizing styrene to 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer, etc. Examples of the 2,6-dialkylphenol / 2,3,6-trialkylphenol copolymer include 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer, 2,6-dimethylphenol / 2,3,6-triethylphenol copolymer, 2,6-diethylphenol / 2,3,6-trimethylphenol copolymer, 2,6-dipropylphenol / 2,3,6-trimethylphenol copolymer, etc.

[0017] Among these, poly(2,6-dimethyl-1,4-phenylene ether) and 2,6-dimethylphenol / 2,3,6-trimethylphenol random copolymer are particularly preferred as polyphenylene ether resins. As the polyphenylene ether resins, for example, as described in JP-A-2005-344065, polyphenylene ether resins having a specified number of terminal groups and copper content can also be suitably used.

[0018] The polyphenylene ether resin used in this embodiment may be a recycled product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or a scrap material used in molding a polyphenylene ether resin.

[0019] The molecular weight of the polyphenylene ether resin is preferably 0.2 dL / g or more, more preferably 0.3 dL / g or more, in terms of the viscosity average molecular weight obtained by converting from the intrinsic viscosity measured at a temperature of 30°C using chloroform as a solvent. By setting the viscosity average molecular weight of the polyphenylene ether resin to one in which the intrinsic viscosity is 0.2 dL / g or more, the mechanical strength of the resin composition tends to be improved. In addition, the intrinsic viscosity is preferably 0.8 dL / g or less, more preferably 0.6 dL / g or less. By setting the viscosity average molecular weight of the polyphenylene ether resin to one in which the intrinsic viscosity is 0.8 dL / g or less, the flowability of the resin composition tends to be improved, and as a result, the molding process of the resin composition tends to be facilitated. In addition, it is also preferable to adjust the intrinsic viscosity of the polyphenylene ether resin within the intrinsic viscosity range by using two or more polyphenylene ether resins having different intrinsic viscosities in combination.

[0020] The method for producing the polyphenylene ether resin is not particularly limited, and known methods can be used. For example, the polyphenylene ether resin can be produced by a method such as oxidative polymerization of a monomer such as 2,6-dimethylphenol in the presence of an amine copper catalyst. In this case, the intrinsic viscosity can be controlled within a desired range by selecting reaction conditions. For example, the control of the intrinsic viscosity can be achieved by selecting conditions such as polymerization temperature, polymerization time, and catalyst amount.

[0021] <Polystyrene resin> The resin composition of the present embodiment may contain a styrene-based resin. Examples of the styrene-based resin include a polymer of a styrene-based monomer, a copolymer of a styrene-based monomer and another copolymerizable monomer, and a styrene-based graft copolymer. In this embodiment, a resin that is a styrene-based resin and also a block copolymer, which will be described later, is classified as a block copolymer.

[0022] More specifically, the styrene resin may be polystyrene (PS), high impact polystyrene (HIPS), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), methyl methacrylate-acrylonitrile-butadiene-styrene copolymer (MABS resin), acrylonitrile-acrylic rubber-styrene copolymer (AAS resin), acrylonitrile-ethylene propylene rubber-styrene copolymer (AES resin), styrene-IPN type rubber copolymer, or a mixture thereof. The styrene resin may have stereoregularity such as syndiotactic polystyrene. Among these, polystyrene and high impact polystyrene are preferred as the styrene resin, and high impact polystyrene is particularly preferred from the viewpoint of improving the impact resistance of the resin composition.

[0023] The high-impact polystyrene used as the styrene-based resin in this embodiment is obtained, for example, by polymerizing at least a styrene-based monomer in the presence of rubber. In the high-impact polystyrene, fine rubber particles are blended or graft-polymerized in a matrix of a styrene-based polymer. Examples of the rubber include polybutadiene, styrene-butadiene copolymer, polyisoprene, and ethylene-propylene copolymer. Examples of the styrene-based polymer include polystyrene and copolymers of styrene and other copolymerizable monomers. Among them, polystyrene is preferred.

[0024] In addition, examples of the styrene-based polymer include a polymer consisting of a repeating unit represented by formula (2) and a copolymer containing 50 mass % or more of a repeating unit represented by formula (2) and other copolymerizable monomers.

[0025] [ka]

[0026] In formula (2), R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Z is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a halogen atom. n is an integer of 1 to 5.

[0027] Furthermore, examples of monomers other than styrene monomers that can be copolymerized with styrene monomers include vinyl monomers such as acrylonitrile and methyl (meth)acrylate.

[0028] The content of the rubber polymer component in the impact resistant polystyrene is preferably 1% by mass or more, more preferably 4% by mass or more, and even more preferably 8% by mass or more. The content of the rubber polymer component in the impact resistant polystyrene is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less. When the impact resistant polystyrene contains a monomer component other than a styrene-based monomer, the sum of the contents of the rubber polymer component and the styrene-based monomer component in the impact resistant polystyrene is preferably 85% by mass or more, and more preferably 90% by mass or more.

[0029] The rubber polymer component in the high-impact polystyrene is distributed throughout the polystyrene matrix in the form of particles, and is mainly composed of a multi-cell structure. The volume average particle diameter of this particulate rubber polymer component (hereinafter referred to as rubber particles) is preferably 0.1 to 2.0 μm, more preferably 0.2 to 1.5 μm, and even more preferably 0.3 to 1.0 μm. By blending high-impact polystyrene containing rubber particles with such a volume average particle diameter, the impact resistance, surface gloss, and colorability of the resin composition tend to be improved.

[0030] The volume average particle diameter of the rubber particles in the high-impact polystyrene is determined by observing a photograph of a sample prepared by staining an ultrathin slice of the target high-impact polystyrene with an osmium tetroxide aqueous solution with a transmission electron microscope, and using the following formula: For example, the volume average particle diameter of the rubber particles can be calculated by using the following formula for about 500 to about 700 rubber particles in the transmission electron microscope photograph. Volume average particle size = Σ(ni·Di 4 ) / Σ(ni·Di 3 )

[0031] In this formula, ni represents the number of rubber particles with a particle diameter Di. The measurement interval for the particle diameter Di is 0.1 μm, and if the shape of the rubber particle in the photograph cannot be regarded as a circle, the particle diameter Di is measured assuming it to be equivalent to a circle.

[0032] As a manufacturing process of high-impact polystyrene having a volume average particle size of 0.1 to 2.0 μm, for example, a known method described in JP-A-3-28210 can be used. Examples of commercially available products of high-impact polystyrene having the above volume average particle size include HT478 manufactured by PS Japan Co., Ltd., and XL1 and XL4 manufactured by Toyo Styrene Co., Ltd.

[0033] The weight average molecular weight (Mw) of the styrene resin is, for example, preferably 50,000 or more, more preferably 100,000 or more, and even more preferably 150,000 or more. The upper limit of the Mw of the styrene resin is, for example, preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 300,000 or less. The Mw of the styrene resin can be measured by a measurement method such as size exclusion chromatography.

[0034] The styrene-based resin used in this embodiment may be a recycled product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or a scrap material obtained when molding a styrene-based resin.

[0035] The method for producing the styrene resin is not particularly limited, and known methods can be used. For example, the styrene resin can be produced by emulsion polymerization, solution polymerization, suspension polymerization, bulk polymerization, or the like. As the styrene resin, one type of styrene resin may be used alone, or two or more types of styrene resins may be used in combination.

[0036] <Blend ratio of polyphenylene ether resin and polystyrene resin> The resin composition of the present embodiment contains 50 to 100 parts by mass of a polyphenylene ether resin and 50 to 0 parts by mass of a polystyrene resin. The resin composition of the present embodiment preferably contains 75 to 100 parts by mass of the polyphenylene ether-based resin, and more preferably contains 80 to 100 parts by mass of the polyphenylene ether-based resin, per 100 parts by mass of the total of the polyphenylene ether-based resin and the polystyrene-based resin.

[0037] In the resin composition of this embodiment, the total content of the polyphenylene ether resin and the polystyrene resin blended as necessary is preferably 40 mass% or more of the resin composition, more preferably 45 mass% or more, and even more preferably 50 mass% or more, and is preferably 64 mass% or less, more preferably 60 mass% or less, and even more preferably 57 mass% or less. The polyphenylene ether resin may include only one type, or may include two or more types. In addition, when a polystyrene-based resin is contained, only one type may be contained, or two or more types may be contained. When two or more of these resins are contained in total, the total amount is preferably in the above range.

[0038] The resin composition of the present embodiment may or may not contain a thermoplastic resin other than the polyphenylene ether-based resin, the polystyrene-based resin, and the block copolymer. Examples of thermoplastic resins other than those mentioned above include olefin-based resins such as polyamide resins, polyester resins, polyphenylene sulfide resins, liquid crystal polyester resins, polycarbonate resins, polyacetal resins, polyacrylonitrile resins, acrylic resins, polyethylene resins, and polypropylene resins. The total amount of the thermoplastic resins is preferably less than 10% by mass, more preferably less than 5% by mass, even more preferably less than 3% by mass, and even more preferably less than 1% by mass, in 100% by mass of the resin composition. The resin composition of the present embodiment is preferably substantially free of thermoplastic resins other than polyphenylene ether resins, polystyrene resins, and block copolymers. By "substantially free," it is meant that the content of thermoplastic resins other than polyphenylene ether resins, polystyrene resins, and block copolymers contained in the resin composition is preferably less than 5% by mass, more preferably less than 3% by mass, and even more preferably less than 1% by mass of the resin composition.

[0039] <Talc> The resin composition of the present embodiment contains talc, and the talc contains 2.5 to 10 mass % of calcium and 50 to 60 mass % of silicon calculated as oxides based on fluorescent X-ray analysis. By using such talc, it is possible to improve tracking resistance while maintaining other physical properties at high levels.

[0040] The amount of calcium in the talc, calculated as oxide based on fluorescent X-ray analysis, is preferably 3% by mass or more, and is preferably 9% by mass or less, more preferably 7% by mass or less, and even more preferably 5% by mass or less. By making it equal to or more than the lower limit, tracking resistance tends to be further improved. Also, by making it equal to or less than the upper limit, the strength and elastic modulus of the obtained molded product tend to be improved despite the inclusion of talc.

[0041] The amount of silicon in the talc calculated as oxide based on fluorescent X-ray analysis is preferably 51% by mass or more, more preferably 53% by mass or more, even more preferably 54% by mass or more, even more preferably 55% by mass or more, even more preferably 57% by mass or more, and preferably 59% by mass or less. By making it equal to or more than the lower limit, the elastic modulus of the obtained molded article tends to be improved. Also, by making it equal to or less than the upper limit, the tracking resistance tends to be further improved.

[0042] The amount of aluminum in the talc calculated as oxide based on fluorescent X-ray analysis is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less. By making it equal to or more than the lower limit, tracking resistance tends to be improved. Also, by making it equal to or less than the upper limit, the deflection temperature under load of the obtained molded product tends to be improved.

[0043] The amount of chlorine in the talc based on fluorescent X-ray analysis is preferably less than 0.01% by mass, more preferably less than 0.001% by mass, and even more preferably not detectable. A small amount of chlorine tends to improve tracking resistance. In addition, the amount of halogen atoms in the talc based on fluorescent X-ray analysis is preferably less than 0.01 mass%, more preferably less than 0.001 mass%, and even more preferably not detectable. The smaller amount of halogen atoms tends to further improve tracking resistance. The X-ray fluorescence analysis is performed according to the method described in the Examples below.

[0044] The median diameter (D 50 ) is preferably 10 μm or more, more preferably 11 μm or more, even more preferably 12 μm or more, even more preferably 13 μm or more, even more preferably 14 μm or more, and is preferably 25 μm or less, more preferably 21 μm or less, even more preferably 19 μm or less, even more preferably 17 μm or less, and even more preferably 16 μm or less. By making it equal to or more than the lower limit, tracking resistance tends to be further improved. Also, by making it equal to or less than the upper limit, impact resistance of the obtained molded article tends to be improved. When the resin composition of the present embodiment contains two or more types of talc, the median diameter of the talc is the median diameter of the mixture.

[0045] The talc may be surface-treated with at least one compound selected from polyorganohydrogensiloxanes and organopolysiloxanes. In this case, the amount of the siloxane compound attached to the talc is preferably 0.1 to 5% by mass of the talc.

[0046] The whiteness of the talc used in this embodiment is preferably not less than 85 and not more than 91. The whiteness is measured according to the description in the examples described later.

[0047] The content of talc in the resin composition of this embodiment is 20 parts by mass or more, preferably 22 parts by mass or more, more preferably 24 parts by mass or more, even more preferably 25 parts by mass or more, and even more preferably 26 parts by mass or more, relative to the total 100 parts by mass of 50 to 100 parts by mass of polyphenylene ether resin and 50 to 0 parts by mass of polystyrene resin, and is 40 parts by mass or less, preferably 38 parts by mass or less, more preferably 36 parts by mass or less, even more preferably 34 parts by mass or less, even more preferably 32 parts by mass or less, even more preferably 30 parts by mass or less, even more preferably 29 parts by mass or less, and may be 28 parts by mass or less. By making it equal to or more than the lower limit, the reinforcing effect of the resin composition or molded article tends to be further improved. Also, by making it equal to or less than the upper limit, the decrease in impact resistance of the obtained molded article tends to be more effectively suppressed. The resin composition of the present embodiment may contain only one type of talc, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0048] <Block copolymer> The resin composition of the present embodiment contains a block copolymer. The melt mass flow rate (MFR) of the block copolymer measured in accordance with JIS K7210 is 3 g / 10 min or less under the measurement conditions of a temperature of 230° C. and a load of 2.16 kg. By containing such a block copolymer, the impact resistance and tracking resistance of the resulting molded article can be effectively improved. The MFR is preferably 2 g / 10 min or less, more preferably 1 g / 10 min or less, and even more preferably 0.5 g / 10 min or less. The lower limit of the MFR is that there is no flow under the above measurement conditions. By making the MFR equal to or less than the upper limit, impact resistance tends to be improved. In addition, tracking resistance tends to be improved. When the resin composition of the present embodiment contains two or more types of block copolymers, the MFR of the mixture preferably falls within the above range. The MFR is measured as described in the Examples section below.

[0049] The block copolymer in this embodiment preferably contains a vinyl aromatic compound block and a conjugated diene compound block, and the vinyl aromatic compound block and the conjugated diene compound block preferably account for 90 mass % or more of the block copolymer. The block copolymer is a resin component contained in the resin composition mainly for the purpose of improving the impact resistance of the resin composition. The block copolymer used in the present embodiment is preferably a hydrogenated product, and may be a partially hydrogenated product or a completely hydrogenated product. Specifically, the hydrogenation rate of the block copolymer is preferably 80% or more, more preferably 90% or more, even more preferably 95% or more, and particularly preferably 98% or more.

[0050] The vinyl aromatic compound block is a polymer block containing a vinyl aromatic compound as a main component. That is, the content of the vinyl aromatic compound is more than 50% by mass in 100% by mass of the vinyl aromatic compound block. The content of the vinyl aromatic compound is preferably 70% by mass or more, more preferably 80% by mass or more. The upper limit of the content of the vinyl aromatic compound is not particularly limited, but is preferably 100% by mass or less.

[0051] Examples of the vinyl aromatic compound contained in the vinyl aromatic compound block include styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene, diphenylethylene, etc. Among these, styrene is particularly preferred as the vinyl aromatic compound. The vinyl aromatic compound block may contain one type of vinyl aromatic compound alone or two or more types of vinyl aromatic compounds.

[0052] The conjugated diene compound block is a polymer block containing a conjugated diene compound as a main component. That is, the content of the conjugated diene compound is more than 50% by mass out of 100% by mass of the conjugated diene compound block. The content of the conjugated diene compound is preferably 70% by mass or more, and more preferably 80% by mass or more. The upper limit of the content of the conjugated diene compound is not particularly limited, but is preferably 100% by mass or less.

[0053] Examples of the conjugated diene compounds contained in the conjugated diene compound block include butadiene, isoprene, 1,3-pentadiene, and 2,3-dimethyl-1,3-butadiene. Among these, butadiene, isoprene, and combinations thereof are preferred as the conjugated diene compounds. In the conjugated diene compound block, one type of conjugated diene compound may be used alone, or two or more types of conjugated diene compounds may be used.

[0054] The molecular structure of the block copolymer is not particularly limited as long as it contains a structure in which a vinyl aromatic compound block and a conjugated diene compound block are bonded, and may be linear, branched, radial, or a combination of two or more of these. Examples of the block copolymer used in this embodiment include styrene-ethylene-propylene (SEP), styrene-ethylene-propylene-styrene (SEPS), styrene-ethylene-ethylene-propylene-styrene (SEEPS), and styrene-ethylene-butylene-styrene (SEBS), with SEPS being preferred. In the block copolymer containing the above-mentioned vinyl aromatic compound block and conjugated diene compound block, the content of the vinyl aromatic compound block in 100% by mass of the block copolymer is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 18% by mass or more, and is preferably 45% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less.

[0055] The content of the block copolymer in the resin composition of this embodiment is 10 parts by mass or more, preferably 11 parts by mass or more, more preferably 13 parts by mass or more, more preferably 15 parts by mass or more, even more preferably 16 parts by mass or more, even more preferably 17 parts by mass or more, and 30 parts by mass or less, preferably 28 parts by mass or less, more preferably 26 parts by mass or less, even more preferably 24 parts by mass or less, even more preferably 22 parts by mass or less, and even more preferably 20 parts by mass or less, relative to the total 100 parts by mass of 50 to 100 parts by mass of the polyphenylene ether resin and 50 to 0 parts by mass of the polystyrene resin. By making it equal to or more than the lower limit, the impact resistance of the obtained molded article can be more effectively improved. Also, by making it equal to or less than the upper limit, the flame retardancy of the obtained molded article tends to be improved. The resin composition of the present embodiment may contain only one type of block copolymer, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0056] <Flame retardants> The resin composition of the present embodiment contains a flame retardant. By containing the flame retardant, the flame retardancy of the obtained molded article can be improved. In addition, the tracking resistance can be improved. The flame retardant is not particularly limited as long as it improves the flame retardancy of the resulting molded article. Examples of the flame retardant include phosphorus-based flame retardants, halogen-based flame retardants, and organometallic flame retardants. Of these, phosphorus-based flame retardants that are compatible with the above-mentioned polyphenylene ether resin are preferred.

[0057] Examples of phosphorus-based flame retardants include metal ethylphosphinate, metal diethylphosphinate, melamine polyphosphate, condensed phosphate, and phosphazene compounds. Among these, condensed phosphate or phosphazene compounds are preferred, and condensed phosphate is more preferred. As the flame retardant, one type of flame retardant may be used alone, or two or more types of flame retardants having different compositions may be used in combination.

[0058] In particular, when a phosphorus-based flame retardant is used as the flame retardant, the phosphorus-based flame retardant is preferably, for example, a phosphoric acid ester represented by formula (3).

[0059] [ka]

[0060] In formula (3), R 1 , R 2 , R 3 , R 4 each independently represents an aryl group. The aryl group may be substituted or unsubstituted. X represents a divalent aromatic group. The divalent aromatic group may or may not have another substituent. n represents an integer of 0 to 5.

[0061] R 1 , R 2 , R 3 , R 4 The aryl group represented by each of R includes, for example, a phenyl group, a naphthyl group, etc., with the phenyl group being preferred. The divalent aromatic group represented by X includes, for example, a phenylene group, a naphthylene group, or a group derived from a bisphenol, with the phenylene group being preferred. 1 , R 2 , R 3 , R 4 The substituents in each of and X are preferably, for example, an alkyl group, an alkoxy group, or a hydroxy group. When the integer n is 0, the phosphate ester flame retardant represented by formula (3) is a phosphate. When the integer n is any of 1 to 5, the phosphate ester flame retardant represented by formula (3) is a condensed phosphate. The condensed phosphate may be a mixture. In this embodiment, condensed phosphate esters are preferred.

[0062] Examples of such phosphate ester flame retardants include triphenyl phosphate, bisphenol A bisphosphate, hydroquinone bisphosphate, resorcinol bisphosphate, or substitution products, condensates, etc. Commercially available phosphate ester flame retardants include, for example, "TPP" (triphenyl phosphate), "CR733S" (resorcinol bis(diphenyl phosphate)), "CR741" (bisphenol A bis(diphenyl phosphate)), "PX-200" (resorcinol bis(dixylenyl phosphate)) manufactured by Daihachi Chemical Industry Co., Ltd., and "FP-900L" (biphenyl-4,4'-diol bis(diphenyl phosphate)) manufactured by ADEKA Corporation, and are easily available.

[0063] The content of the flame retardant (preferably a phosphorus-based flame retardant) in the resin composition of this embodiment is 15 parts by mass or more, preferably 16 parts by mass or more, more preferably 18 parts by mass or more, more preferably 20 parts by mass or more, even more preferably 21 parts by mass or more, even more preferably 22 parts by mass or more, and 40 parts by mass or less, preferably 35 parts by mass or less, more preferably 33 parts by mass or less, even more preferably 30 parts by mass or less, even more preferably 27 parts by mass or less, and even more preferably 25 parts by mass or less, relative to the total 100 parts by mass of 50 to 100 parts by mass of the polyphenylene ether resin and 50 to 0 parts by mass of the polystyrene resin. By making the content equal to or more than the lower limit, the combustion time of the obtained molded article can be shortened and the fluidity of the resin composition tends to be improved. In addition, by making the content equal to or less than the upper limit, the deterioration of the heat resistance and impact resistance of the obtained molded article tends to be more effectively suppressed. The resin composition of the present embodiment may contain only one type of flame retardant (preferably a phosphorus-based flame retardant), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0064] <Calcium carbonate> The resin composition of the present embodiment contains calcium carbonate. By containing calcium carbonate, tracking resistance can be improved. In this embodiment, when calcium carbonate is in the state of a raw material (before being contained in a resin composition), the average particle size of the primary particles of calcium carbonate is preferably 0.1 μm or more, more preferably 0.15 μm or more, and preferably 15 μm or less, more preferably 5 μm or less. The average particle size of the primary particles of calcium carbonate can be obtained by arithmetically averaging the average particle size of the primary particles of particles in a photograph taken by observation using a scanning electron microscope (SEM). By setting the average particle size of the primary particles of calcium carbonate to the above lower limit or more, the obtained molded product tends to have improved tracking resistance while maintaining high impact resistance. In addition, by setting it to the above upper limit or less, dispersion during melt kneading is improved.

[0065] The calcium carbonate may be surface-treated. The surface treatment applied to the calcium carbonate is not particularly limited, and examples thereof include surface treatment with a fatty acid, a resin acid, silicic acid, phosphoric acid, a silane coupling agent, an alkylarylsulfonic acid or a salt thereof, and the like. Examples of the fatty acid include saturated or unsaturated fatty acids having 6 to 31 carbon atoms, and preferably saturated or unsaturated fatty acids having 12 to 28 carbon atoms. Among them, calcium carbonate surface-treated with a fatty acid is preferred from the viewpoint of dispersibility and handling during production. When calcium carbonate surface-treated with a fatty acid is used as calcium carbonate, calcium carbonate is more uniformly dispersed in the polyphenylene ether resin, and thus the tracking resistance of the obtained molded article tends to be further improved.

[0066] The content of calcium carbonate in the resin composition of the present embodiment is 5 parts by mass or more, preferably 6 parts by mass or more, more preferably 7 parts by mass or more, even more preferably 8 parts by mass or more, and even more preferably 9 parts by mass or more, relative to the total 100 parts by mass of 50 to 100 parts by mass of polyphenylene ether resin and 50 to 0 parts by mass of polystyrene resin, and is 40 parts by mass or less, preferably 35 parts by mass or less, more preferably 30 parts by mass or less, even more preferably 25 parts by mass or less, even more preferably 20 parts by mass or less, even more preferably 15 parts by mass or less, and may be 12 parts by mass or less. By making it equal to or more than the lower limit, the tracking resistance of the obtained molded article tends to be further improved. Also, by making it equal to or less than the upper limit, the mechanical strength such as rigidity and impact resistance, heat resistance and fluidity of the obtained molded article tend to be further improved. The resin composition of the present embodiment may contain only one type of calcium carbonate, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0067] Calcium carbonate, by its endothermic dilution action due to its own dehydration or decomposition, suppresses the generation of carbonized components and promotes the volatilization of the carbonized components, and as a result, it is possible to improve the tracking resistance of the obtained molded article by itself. In addition, calcium carbonate can assist the flame retardant in imparting flame retardancy to the resin composition, and thus tends to improve the flame retardancy of the resin composition in cooperation with the flame retardant.

[0068] <Other ingredients> The resin composition of the present embodiment may contain other components in addition to those described above. Examples of other components include resin additives and fillers other than those described above.

[0069] The resin additives may include lubricants (fatty acid metal salts, polyethylene wax, etc.), stabilizers, dyes, pigments, release agents (silicone oils, fatty acids, fatty acid esters, etc.), antioxidants, weather resistance improvers, nucleating agents, impact resistance improvers, plasticizers, flow improvers, etc. The total amount of these resin additives is preferably less than 10% by mass, more preferably less than 5% by mass, and even more preferably less than 3% by mass, based on 100% by mass of the resin composition. For the internal lubricant, the description in paragraphs 0029 to 0035 of WO 2019 / 026689 can be referred to, the contents of which are incorporated herein. In addition, the resin composition of this embodiment can be blended with additives described in paragraphs 0047 to 0103 of WO 2021 / 241471 within the scope of the present invention, the contents of which are incorporated herein.

[0070] Examples of fillers other than the above include glass fiber, carbon fiber, etc. The total amount of fillers other than the above in the resin composition of this embodiment is preferably less than 10 mass%, more preferably less than 5 mass%, even more preferably less than 3 mass%, and even more preferably less than 1 mass%, based on 100 mass% of the resin composition.

[0071] In the resin composition of the present embodiment, the total of the polyphenylene ether resin, the polystyrene resin blended as necessary, the talc, the block copolymer, the flame retardant, and the calcium carbonate preferably accounts for 90 mass % or more of the resin composition, more preferably 95 mass % or more, and even more preferably 97 mass % or more. In the resin composition of the present embodiment, the total of the polyphenylene ether resin, the polystyrene resin blended as necessary, the talc, the block copolymer, the flame retardant, the calcium carbonate, and the stabilizer preferably accounts for 95 mass % or more of the resin composition, more preferably 97 mass % or more, and even more preferably 99 mass % or more.

[0072] <<Stabilizer>> The stabilizers include heat stabilizers and antioxidants. Examples of the stabilizer include a phenol-based stabilizer, an amine-based stabilizer, a phosphorus-based stabilizer, a thioether-based stabilizer, etc. Among these, in the present embodiment, it is preferable to include a phosphorus-based stabilizer and / or a phenol-based stabilizer.

[0073] Any known phosphorus stabilizer can be used. Specific examples include phosphorus oxoacids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; metal acid pyrophosphates such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; phosphates of Group 1 or Group 2B metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds, with organic phosphite compounds being particularly preferred.

[0074] Examples of organic phosphite compounds include triphenyl phosphite, tris(mononylphenyl)phosphite, tris(mononyl / dinonyl phenyl)phosphite, tris(2,4-di-tert-butylphenyl)phosphite, monooctyl diphenyl phosphite, dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, and 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite. Specific examples of such organic phosphite compounds include "ADK STAB (registered trademark; the same applies below) 1178," "ADK STAB 2112," and "ADK STAB HP-10" manufactured by ADEKA Corporation, "JP-351," "JP-360," and "JP-3CP" manufactured by Johoku Chemical Industry Co., Ltd., and "IRGAFOS (registered trademark; the same applies below) 168" manufactured by BASF.

[0075] As the phenol-based stabilizer, a hindered phenol-based stabilizer is preferably used. Specific examples of hindered phenol stabilizers include pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide], 2,4-dimethyl-6-(1-methylpentadecyl)phenol, diethyl[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphate, 3,3',3'',5,5',5''-hexa-tert-butyl-a,a',a''-(mesityle) 4,6-bis(octylthiomethyl)-o-cresol, ethylene bis(oxyethylene) bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], hexamethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-tert-butyl -4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol, 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate, and the like.

[0076] Among them, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate are preferred. Specific examples of such hindered phenol stabilizers include "Irganox (registered trademark, the same applies below) 1010" and "Irganox 1076" manufactured by BASF, and "Adeka STAB AO-50" and "Adeka STAB AO-60" manufactured by ADEKA.

[0077] The content of the stabilizer in the resin composition of the present embodiment is usually 0.001 parts by mass or more, preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, and usually 5 parts by mass or less, preferably 3 parts by mass or less, relative to 100 parts by mass of the total amount of the polyphenylene ether resin and the polystyrene resin. By setting the content of the stabilizer within the above range, the effect of adding the stabilizer is more effectively exhibited. The resin composition of the present embodiment may contain only one type of stabilizer, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0078] <Physical properties of resin composition> The resin composition of the present embodiment is preferably excellent in tracking resistance. Specifically, the resin composition is molded into a test piece of 100 mm x 150 mm x 3.2 mm, and the CTI value measured by a measurement method conforming to IEC60112 is preferably 500 V or more, more preferably 550 V or more, and even more preferably 600 V or more. The upper limit of the CTI value is preferably the measurement limit value. In the device used in the examples described later, the measurement limit value is 600 V. The CTI value is measured as described in the Examples section below.

[0079] <Method of producing resin composition> The method for producing the resin composition of this embodiment is not limited, and known methods for producing resin compositions can be widely adopted. Examples of the method include a method in which a polyphenylene ether resin, a polystyrene resin blended as necessary, talc, a block copolymer, a flame retardant, calcium carbonate, and other components blended as necessary are mixed in advance using various mixers such as a tumbler or a Henschel mixer, and then melt-kneaded with a mixer such as a Banbury mixer, a roll, a Brabender, a single-screw kneading extruder, a twin-screw kneading extruder, or a kneader. The temperature for melt-kneading is not particularly limited, but is usually in the range of 240 to 320°C. An example of the resin composition is a pellet.

[0080] <Molded products> The molded article of the present embodiment is formed from the resin composition or pellets of the present embodiment. In the present embodiment, a molded article may be produced by pelletizing the resin composition and molding the resulting pellets by various molding methods. Alternatively, a molded article may be produced by directly molding a resin composition that has been melt-kneaded in a kneader without going through the pelletizing process. The above-mentioned resin composition (e.g., pellets) is molded into a molded product by various molding methods. The shape of the molded product is not particularly limited and can be appropriately selected depending on the use and purpose of the molded product, and examples thereof include film-like, rod-like, cylindrical, annular, circular, elliptical, polygonal, irregular, hollow, frame-like, box-like, panel-like, button-like, etc.

[0081] The method for forming the molded article is not particularly limited, and a conventionally known molding method can be adopted, for example, injection molding, injection compression molding, extrusion molding, profile extrusion, transfer molding, hollow molding, gas-assisted hollow molding, blow molding, extrusion blow molding, IMC (in-mold coating molding) molding, rotational molding, multi-layer molding, two-color molding, insert molding, sandwich molding, foam molding, pressure molding, etc. In particular, the resin composition of this embodiment is suitable for molded articles obtained by injection molding, injection compression molding, and extrusion molding. However, it goes without saying that the resin composition of this embodiment is not limited to molded articles obtained by these methods.

[0082] <Applications of resin composition> The resin composition of the present embodiment can be widely used in applications in which polyphenylene ether-based resins, in particular blends of polyphenylene ether-based resins and styrene-based resins, are generally used. For example, it is suitable for automobile exterior and exterior panel parts, automobile interior parts, and automobile underhood parts, such as bumpers, fenders, door panels, moldings, emblems, engine hoods, wheel covers, roofs, spoilers, engine covers, breaker cases, electrical cover cases, coil cases, and other exterior and exterior panel parts, underhood parts, and interior parts such as instrument panels and console box trim. They can also be used as components for various computers and their peripheral devices, other office automation equipment, cabinets and chassis for televisions, videos, various disk players, refrigerators, air conditioners, liquid crystal projectors, and the like. Furthermore, the material can be used as a coating for electric wires and cables obtained by coating metal conductors or optical fibers, fuel cases for solid methanol batteries, secondary battery containers, fuel cell water pipes, water-cooling tanks, boiler exterior cases, ink-peripheral parts and components and chassis for inkjet printers, as well as molded articles such as water piping and joints, and lithium-ion battery separators obtained by stretching the sheets and films. EXAMPLES

[0083] The present invention will be described in more detail below with reference to examples. The materials, amounts, ratios, processing contents, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0084] 1.Raw materials The raw materials shown in Table 1 below were used. [Table 1]

[0085] MFR is the melt mass flow rate measured in accordance with JIS K7210. MFR was measured at a temperature of 230° C. and a load of 2.16 kg. The unit is g / 10 min. If no flow was observed when measured under the above conditions, it was indicated as "No flow." Details of the above talc are as follows: [Table 2]

[0086] <Talc whiteness> The whiteness of the talc was measured using a Hunter whiteness index spectrophotometer. For the measurement, SE6000 manufactured by Nippon Denshoku Industries Co., Ltd. was used.

[0087] <Talc composition> The composition of talc was measured by X-ray fluorescence analysis and calculated in terms of oxides. Specifically, it was evaluated by semi-quantitative measurement. The total of oxides was set to 100 mass%, and the proportion of each oxide, except for chlorine, was shown in mass%. For the measurements, a Rigaku Supermini200 was used.

[0088] Example 1, Comparative Examples 1 to 8 <Compound> The components shown in Tables 1 and 2 were mixed in the ratios (units: mass%) shown in Tables 3 or 4, and the mixture of the components was melt-kneaded using a twin-screw extruder (Shibaura Machine Co., Ltd.: TEM18SS) at a cylinder temperature of 280°C and a screw rotation speed of 300 rpm, extruded into strands, and the strands were cut (pelletized) to obtain pellets of the resin composition.

[0089] <Tracking resistance> The pellets of the resin composition obtained above were dried at 100°C for 2 hours, and then fed to an injection molding machine (Shibaura Machine Co., Ltd.: EC160NII) to produce a molded product with a length x width x thickness of 100 mm x 150 mm x 3.2 mm. At this time, the injection molding conditions were a cylinder temperature of 280°C and a mold temperature of 70°C. Using the molded product produced in this manner, the maximum voltage at which tracking breakdown of the molded product did not occur, i.e., the CTI value (unit: V), was measured by a measurement method based on IEC60112 (electrolyte used: solution A, number of drops: 50 drops). The maximum value was 600V.

[0090] <Flame retardancy> The pellets of the resin composition obtained above were dried at 100°C for 2 hours, and then fed into an injection molding machine (Shibaura Machine Co., Ltd.: EC75SX) to mold a test piece for a flammability test having a length x width x thickness of 125 mm x 13 mm x 1.5 mm. At this time, the injection molding conditions were a cylinder temperature of 280°C and a mold temperature of 70°C. The obtained flammability test specimens were subjected to a vertical flammability test (UL94V test: 1.5mmt) in accordance with the UL94 standard, with each set of five specimens being subjected to two tests. In the evaluation of flame retardancy, a grade was determined for each set based on the vertical flammability test. The grades are classified as V-0, V-1, and V-2, from best to worst. In the evaluation of flame retardancy, a maximum burning time of 30 seconds or more and a result that did not fall into any of the grades was determined to be NG.

[0091] <MVR(メルトボリュームレート)> The MVR of the resin composition was measured in accordance with JIS K7210. Among the measurement conditions for MVR, the temperature was 280 °C and the load was 5 kg. The unit was shown as cm 3 / 10 min.

[0092] <DTUL (heat deflection temperature)> After drying the pellets of the resin composition obtained above at 100 °C for 2 hours, they were supplied to an injection molding machine (manufactured by Shibaura Machine Co., Ltd.: EC75SX), and an A-type test piece of ISO 3167:93 (hereinafter referred to as an ISO test piece) was injection molded in accordance with ISO 15103. At this time, as the injection molding conditions, the cylinder temperature was 280 °C and the mold temperature was 70 °C. In accordance with ISO 75-2 obtained above, the parallel part of the above ISO test piece was machined to produce a strip-shaped test piece with a length × width × thickness = 80 mm × 10 mm × 4 mm. Using this test piece, the heat deflection temperature (unit: °C) was measured under the condition of a load of 1.80 MPa.

[0093] <Charpy (notched Charpy impact strength)> Regarding the above-obtained ISO test piece, in accordance with ISO 179-1 and ISO 179-2, it was machined to cut off the gripping parts at both ends of the ISO test piece and to notch (make a cutout) in the central part of the ISO test piece to produce a notched Charpy impact test piece. Regarding the Charpy impact test piece thus obtained, as an evaluation of impact resistance, the Charpy impact strength (unit: kJ / m 2 ) at a temperature of 23 °C was measured by the measurement method in accordance with ISO 179-1 and ISO 179-2.

[0094] <Maximum tensile (maximum tensile strength) and elongation rate (tensile elongation rate)> Regarding the above-obtained ISO test piece, the maximum tensile strength (unit: MPa) and the tensile elongation rate (unit: %) were measured in accordance with ISO 527.

[0095] <Flexural strength and flexural modulus> The flexural strength (unit: MPa) and flexural modulus (unit: MPa) of the ISO test pieces obtained above were measured in accordance with ISO178.

[0096] [Table 3]

[0097] [Table 4]

[0098] As is clear from the above results, the molded articles made from the resin compositions of the present invention were excellent in various physical properties and also in tracking resistance.

Claims

1. For a total of 100 parts by mass of 50 to 100 parts by mass of polyphenylene ether resin and 50 to 0 parts by mass of polystyrene resin, 20 to 40 parts by weight of talc; 10 to 30 parts by weight of a block copolymer; 15 to 40 parts by weight of a flame retardant; 5 to 40 parts by weight of calcium carbonate, The talc contains, based on an X-ray fluorescence analysis, 2.5 to 10 mass % of calcium and 50 to 60 mass % of silicon calculated as oxides, The block copolymer has a melt mass flow rate, as measured in accordance with JIS K7210, of 3 g / 10 min or less under measurement conditions of a temperature of 230° C. and a load of 2.16 kg.

2. The median diameter of the talc (D 50 ) is 10 to 25 μm; The resin composition according to claim 1.

3. The resin composition according to claim 1 or 2, wherein the resin composition contains 80 to 100 parts by mass of the polyphenylene ether-based resin per 100 parts by mass of the polyphenylene ether-based resin and the polystyrene-based resin combined.

4. The resin composition according to claim 1 or 2, wherein the talc has a chlorine content of less than 0.01% by mass as determined by fluorescent X-ray analysis.

5. 3. The resin composition according to claim 1, wherein the talc has an aluminum content of 0.1 to 5 mass % calculated as an oxide based on fluorescent X-ray analysis.

6. The resin composition according to claim 1 or 2, wherein the block copolymer comprises a vinyl aromatic compound block and a conjugated diene compound block.

7. The resin composition according to claim 1 or 2, wherein the flame retardant comprises a phosphorus-based flame retardant.

8. The resin composition according to claim 1 or 2, further comprising a phosphorus-based stabilizer and / or a phenol-based stabilizer.

9. The resin composition according to claim 1 or 2, wherein the resin composition is molded into a test piece of 100 mm x 150 mm x 3.2 mm, and the CTI value measured by a measurement method in accordance with IEC 60112 is 500 V or more.

10. The median diameter of the talc (D 50 ) is 10 to 25 μm, the resin composition contains 80 to 100 parts by mass of a polyphenylene ether-based resin per 100 parts by mass of a total of a polyphenylene ether-based resin and a polystyrene-based resin, and the talc has a chlorine content of less than 0.01% by mass based on a fluorescent X-ray analysis; The talc has an aluminum content of 0.1 to 5 mass% calculated as an oxide based on an X-ray fluorescence analysis, the block copolymer comprises a vinyl aromatic compound block and a conjugated diene compound block, The flame retardant includes a phosphorus-based flame retardant, Further, the composition contains a phosphorus-based stabilizer and / or a phenol-based stabilizer, The resin composition according to claim 1, wherein the resin composition is molded into a test piece of 100 mm x 150 mm x 3.2 mm, and the CTI value measured by a measurement method in accordance with IEC 60112 is 500 V or more.

11. A pellet of the resin composition according to claim 1, 2 or 10.

12. A molded article formed from the resin composition according to claim 1, 2 or 10.

13. A molded article formed from the pellets of claim 11.

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