Polybutylene terephthalate resin composition and molded article

Abstract

The objective is to obtain molded products that exhibit excellent flame retardancy, tracking resistance, bleed-out resistance, and weld strength. This invention relates to a polybutylene terephthalate resin composition comprising (A) 100 parts by mass of polybutylene terephthalate resin, (B) 10 to 120 parts by mass of a phosphate ester compound, and (D) 1 to 20 parts by mass of a flame retardant resin, wherein the island phase of the flame retardant resin (D) is dispersed in the sea phase of the polybutylene terephthalate resin (A) with an average diameter of 0.05 to 5.0 μm.

Description

Technical Field

[0001] The present invention relates to a polybutylene terephthalate resin composition and a molded article formed therefrom.

Background Art

[0002] Polybutylene terephthalate resin is utilized in a wide range of fields such as mechanical mechanism parts, electrical and electronic parts, and automotive parts by taking advantage of its excellent injection moldability and various properties such as mechanical properties. However, since polybutylene terephthalate resin is inherently flammable, for use as industrial materials such as mechanical mechanism parts, electrical and electronic parts, and automotive parts, safety against fire, that is, flame retardancy, is required, and in many cases, a high level of flame retardancy showing V-0 of the UL-94 standard is necessary. As a method for imparting flame retardancy to polybutylene terephthalate resin, a method of compounding a halogen-based organic compound as a flame retardant into the resin is common, but due to the increasing environmental awareness, there is a movement concerned about the impact of halogen-based organic compounds on the environment. Therefore, in recent years, it has become strongly desired to use these halogen-free non-halogen-based flame retardants. As non-halogen-based flame retardants, for example, phosphorus-based flame retardants such as phosphinates, phosphazene compounds, and phosphate ester compounds, and nitrogen-based flame retardants such as melamine cyanurate are proposed to be blended as flame retardants. Among them, although the effect of imparting flame retardancy of phosphate ester compounds is low, they are low in cost and excellent in fluidity during molding processing, and thus many polybutylene terephthalate resin compositions have been proposed.

[0003] Examples of flame-retardant resin compositions using phosphate ester compounds include a resin composition comprising thermoplastic polyester, condensed phosphate ester, and methacrylic resin (Patent Document 1), a resin composition comprising polyester resin, phosphate esters, and a resin selected from polyphenylene oxide resin and polyphenylene sulfide resin (Patent Document 2), a resin composition comprising polybutylene terephthalate resin, phosphate ester, and a multilayer polymer (Patent Document 3), and a resin composition comprising polyester resin, phosphate ester, and polyphenylene ether resin and / or polyphenylene sulfide resin and polystyrene resin containing epoxy groups. Furthermore, phosphate ester compounds have the problem of easily causing bleed-out on the surface of molded products, and all of the patent documents attempt to suppress bleed-out originating from phosphate ester compounds by incorporating resin components other than polybutylene terephthalate resin. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2014 / 021101 [Patent Document 2] International Publication No. 2003 / 046083 [Patent Document 3] Japanese Patent Publication No. 2004-075868 [Patent Document 4] Japanese Patent Application Publication No. 10-77396 [Overview of the project] [Problems that the invention aims to solve]

[0005] With the increasing power output of electric vehicles in recent years, electrical systems are increasingly using voltages of 400V or higher. In addition to the flame retardancy that has been required for conventional products, insulating components subjected to high voltages, such as connectors and busbars that connect batteries and inverters, and power module cases, are now required to have tracking resistance (500V or higher), which is resistance to tracking breakdown (conductivity due to carbonization degradation) under high voltages, and hydrolysis resistance, which prevents degradation in more severe high-temperature and high-humidity environments.

[0006] Furthermore, with the increasing complexity of product shapes, such as mechanical components, electrical and electronic components, and automotive parts, weld lines may be formed during injection molding. In such cases, there has been a problem of product breakage occurring at the weld lines, which have low mechanical strength.

[0007] Furthermore, due to growing environmental awareness, in addition to being halogen-free, there is a demand for products that do not contain PFAS, which are organofluorine compounds, and also for products that do not contain fluorine-based resins, which are generally added as anti-dripping agents to enhance flame retardancy.

[0008] In the resin composition disclosed in Patent Document 1, although flame retardancy and tracking resistance are improved by using a combination of phosphate ester and phosphazene or organophosphinate salts, hydrolysis resistance and weld strength are insufficient, and there is a problem that tracking resistance deteriorates in a humid and hot environment.

[0009] In the resin composition disclosed in Patent Document 2, the polyphenylene oxide resin and polyphenylene sulfide resin, which are added to enhance flame retardancy, are prone to carbonization, resulting in insufficient tracking resistance and weld strength, as well as inconsistencies in flame retardancy.

[0010] The resin composition disclosed in Patent Document 3, while exhibiting flame retardancy, suffers from problems with insufficient tracking resistance and bleed-out resistance due to the inclusion of a multilayer polymer incorporated to improve mechanical properties.

[0011] In the resin composition disclosed in Patent Document 4, the polyphenylene oxide resin and polyphenylene sulfide resin, which are blended to enhance flame retardancy, are prone to carbonization, resulting in insufficient tracking resistance and weld strength, as well as inconsistencies in flame retardancy.

[0012] From the above, it has been difficult to obtain a material that has excellent flame retardancy, tracking resistance, and bleed-out resistance, while also having high weld strength suitable for molded products with welded areas, using the technologies disclosed in Patent Documents 1 to 4. Furthermore, none of Patent Documents 1 to 4 mention avoiding the use of fluororesins as anti-dripping agents. Even in compositions where the flame retardancy is described as V-0, the lack of fluororesins results in large variations in burning time, and the flame retardancy is substantially insufficient. Thus, it has been difficult to obtain a material with consistent flame retardancy without using fluororesins.

[0013] The object of the present invention is to provide a polybutylene terephthalate resin composition and a molded article thereof that can be obtained with excellent flame retardancy, tracking resistance, bleed-out resistance, and weld strength. [Means for solving the problem]

[0014] The inventors of the present invention have conducted extensive research to solve the above-mentioned problems and have found that the above-mentioned problems can be solved by blending (A) polybutylene terephthalate resin with 10 to 120 parts by mass of (B) phosphate ester compound and (D) flame retardant resin in a mixture of 100 parts by mass of (A) polybutylene terephthalate resin, and by dispersing the island phase of (D) flame retardant resin with an average diameter of 0.05 to 5.0 μm within the sea phase of (A) polybutylene terephthalate resin, thus arriving at the present invention. That is, the present invention has the following configuration. [1] A polybutylene terephthalate resin composition comprising (A) 100 parts by mass of polybutylene terephthalate resin, (B) 10 to 120 parts by mass of phosphate ester compound, and (D) 1 to 20 parts by mass of flame retardant resin, wherein the island phase of the (D) flame retardant resin is dispersed in the sea phase of the (A) polybutylene terephthalate resin with an average diameter of 0.05 to 5.0 μm. [2] The polybutylene terephthalate resin composition according to [1], wherein 1 to 40 parts by mass of (C) styrene resin are further added to 100 parts by mass of (A) polybutylene terephthalate resin, and the ratio of the amount of (C) styrene resin to the amount of (D) flame retardant resin [(C) styrene resin / (D) flame retardant resin] is 0.5 to 4.0. [3] The polybutylene terephthalate resin composition according to [1] or [2], wherein a composite island phase of (C) a styrene-based resin and (D) a flame-retardant resin is dispersed in the sea phase of (A) a polybutylene terephthalate resin with an average diameter of 1 to 20 μm. [4] The polybutylene terephthalate resin composition according to any one of [1] to [3], wherein the flame-retardant resin (D) is a resin whose mass loss when heated in air from room temperature to 600°C at a heating rate of 40°C / min is 70% by mass or less. [5] The polybutylene terephthalate resin composition according to any one of [1] to [4], wherein the (D) flame retardant resin is a polyphenylene sulfide resin. [6] A polybutylene terephthalate resin composition according to any one of [1] to [5], further comprising 10 to 150 parts by mass of (E) a nitrogen-based flame retardant which is a nitrogen-containing heterocyclic compound having a triazine skeleton, per 100 parts by mass of (A) polybutylene terephthalate resin. [7] A polybutylene terephthalate resin composition according to any one of [1] to [6], further comprising 1 to 40 parts by mass of (F) core-shell rubber per 100 parts by mass of (A) polybutylene terephthalate resin. [8] A polybutylene terephthalate resin composition according to any one of [1] to [7], comprising 100 parts by mass of (A) polybutylene terephthalate resin and further 0.3 to 3.0 parts by mass of (G) a hindered amine compound. [9] The polybutylene terephthalate resin composition according to any one of [1] to [8], wherein the content of polyethylene terephthalate resin, polyphenylene ether resin, and polyetherimide resin is less than 5 parts by mass per 100 parts by mass of the (A) polybutylene terephthalate resin.

[10] (A) A polybutylene terephthalate resin composition according to any one of [1] to [9], wherein the content of fluororesin per 100 parts by mass of polybutylene terephthalate resin is less than 0.5 parts by mass.

[11] (A) A polybutylene terephthalate resin composition according to any one of [1] to

[10] , wherein the content of either a phosphazene compound or an organophosphinate metal salt is less than 5 parts by mass per 100 parts by mass of polybutylene terephthalate resin. A molded article obtained by melt-molding any of the polybutylene terephthalate resin compositions described in

[12] [1] to

[11] . A high-voltage insulating component comprising the polybutylene terephthalate resin composition described in any of

[13] [1] to

[11] .

[14] High-voltage insulating components as described in

[13] , which are either high-voltage connectors, power module cases, or busbars. [Effects of the Invention]

[0015] The polybutylene terephthalate resin composition of the present invention can produce molded articles that are excellent in flame retardancy, tracking resistance, bleed-out resistance, and weld strength. [Modes for carrying out the invention]

[0016] The polybutylene terephthalate resin composition of the present invention is prepared by blending 10 to 120 parts by mass of a phosphate ester compound (hereinafter sometimes abbreviated as component (B)) and 1 to 20 parts by mass of a flame-retardant resin (hereinafter sometimes abbreviated as component (D)) with respect to 100 parts by mass of a polybutylene terephthalate resin (hereinafter sometimes abbreviated as component (A)). The polybutylene terephthalate resin composition is such that the island phase of the flame-retardant resin (D) is dispersed in the sea phase of the polybutylene terephthalate resin (A) with an average diameter of 0.05 to 5.0 μm.

[0017] Polybutylene terephthalate resin has a low limiting oxygen index and will burn if exposed to an open flame or other source of fire. To improve the flame retardancy of polybutylene terephthalate resin, phosphate ester compounds are blended with flame-retardant resins such as polyphenylene ether resin or polyphenylene sulfide resin. However, if the flame-retardant resin is poorly dispersed in the polybutylene terephthalate resin composition, large carbides are formed by discharge under high voltage, reducing insulation and tracking resistance, which in turn leads to variations in flame retardancy and a decrease in weld strength. Furthermore, phosphate ester compounds blended with polybutylene terephthalate resin may bleed out, which is thought to be due to their low compatibility with the polybutylene terephthalate resin. Therefore, it is generally considered appropriate to blend amorphous resins with high affinity for phosphate ester compounds into the polybutylene terephthalate resin composition. However, if the amorphous resin has high compatibility with the polybutylene terephthalate resin, it reduces the crystallinity of the polybutylene terephthalate resin, lowering its heat resistance and making it more susceptible to bleed-out in high-temperature environments. Conversely, if the amorphous resin has low compatibility with the polybutylene terephthalate resin, poor dispersion leads to reduced flame retardancy and weld strength. Therefore, in this invention, the island phases of the flame-retardant resin (D) are dispersed in the sea phase of the polybutylene terephthalate resin (A) such that the average diameter of the island phases is 0.05 to 5.0 μm. During combustion, these island phases of the flame-retardant resin (D) react with phosphate esters to form a dense, non-combustible carbonized layer. The formation of this non-combustible carbonized layer allows for high flame retardancy while suppressing the formation of coarse carbides under high-voltage discharge. This results in excellent tracking resistance, bleed-out resistance, and weld strength, and allows for the production of molded products with consistent flammability even without containing PFAS.

[0018] Here, the polybutylene terephthalate resin composition of the present invention contains reactants formed by the reactions of components (A), (B), and (D) with other components. However, these reactants are produced by complex reactions, and it is impractical to specify their structure. Therefore, the present invention is defined by the components that are blended.

[0019] In the present invention, the (A) polybutylene terephthalate resin may be either polybutylene terephthalate or a polybutylene terephthalate copolymer, or a combination thereof. From the viewpoints of mechanical strength and bleed-out resistance, polybutylene terephthalate is preferably used.

[0020] The polybutylene terephthalate resin is a polymer obtained by polycondensation reaction of terephthalic acid (or its ester-forming derivative such as dimethyl terephthalate) and 1,4-butanediol (or its ester-forming derivative).

[0021] The polybutylene terephthalate copolymer is a polymer obtained by polymerizing terephthalic acid (or its ester-forming derivative such as dimethyl terephthalate) and 1,4-butanediol (or its ester-forming derivative) in the coexistence of other dicarboxylic acids (or their ester-forming derivatives) or other glycols (or their ester-forming derivatives) copolymerizable with these.

[0022] Specific examples of the copolymerizable dicarboxylic acids include isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid, oxalic acid, malonic acid, succinic acid, itaconic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, dimer acid, or their ester-forming derivatives, etc. However, it is not limited to these, and any substance can be used as long as copolymerization is possible. Also, two or more kinds can be used simultaneously. The proportion of the copolymerizable dicarboxylic acid is preferably in the range of 3 to 30 mol% in the total dicarboxylic acid component from the viewpoint of moldability, and more preferably in the range of 3 to 20 mol%.

[0023] <0000On the other hand, examples of copolymerizable glycols include ethylene glycol, propylene glycol, nonanediol, neopentyl glycol, tetramethylcyclobutanediol, isosorbide, dimer diol, polyethylene glycol, polytetramethylene glycol, 2,2-bis(4-hydroxyphenyl)propane, hydroquinone, resorcinol, 1,1-bis(4-hydroxyphenyl)cyclohexane, and 2,2-bis(3-methyl-4-hydroxyphenyl)propane, but are not limited to these; any copolymerizable glycol can be used. Multiple glycols can also be used simultaneously. From the viewpoint of moldability, the proportion of copolymerizable glycols other than 1,4-butanediol is preferably in the range of 3 to 30 mol%, and more preferably in the range of 3 to 20 mol% of the total glycol components.

[0024] Other copolymerizable components include trimellitic acid, pyromellitic acid, glycerin, trimethylolpropane, pentaerythritol, p-hydroxybenzoic acid, ε-caprolactone, and γ-butyrolactone.

[0025] In the present invention, the carboxyl group concentration of the (A) polybutylene terephthalate resin is preferably 35 eq / t or less, more preferably 30 eq / t or less, and even more preferably 20 eq / t or less. The lower limit of the carboxyl group concentration is 0 eq / t. Here, the carboxyl group concentration of the (A) polybutylene terephthalate resin is the value measured by dissolving the (A) polybutylene terephthalate resin in o-cresol / chloroform solvent (mixing volume ratio = 2 / 1) and then titrating with ethanolic potassium hydroxide.

[0026] The (A) polybutylene terephthalate resin used in the present invention preferably has a weight-average molecular weight (Mw) of 8,000 or more in terms of further improving mechanical properties. Furthermore, a weight-average molecular weight (Mw) of 500,000 or less is preferable because it improves fluidity. More preferably it is 300,000 or less, and even more preferably 250,000 or less. In the present invention, the weight-average molecular weight (Mw) of the (A) polybutylene terephthalate resin is a value converted to polymethyl methacrylate (PMMA) as measured by gel permeation chromatography (GPC) using hexafluoroisopropanol as the solvent.

[0027] The intrinsic viscosity of the (A) polybutylene terephthalate resin used in the present invention is preferably 0.36 dl / g or higher, and more preferably 0.50 dl / g or higher, when measured with an o-chlorophenol solution at 25°C, in order to further improve mechanical properties. Furthermore, it is preferably 1.60 dl / g or lower, and more preferably 1.50 dl / g or lower, in order to improve fluidity.

[0028] Examples of (B) phosphate ester compounds used in the present invention include triphenyl phosphate, tris(dimethylphenyl) phosphate, trixylenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, cresyl dixylenyl phosphate, trimethyl phosphate, triethyl phosphate, condensed phosphate esters, acidic phosphate esters, and phosphate ester amides. Two or more of these phosphate ester compounds can also be used in any combination.

[0029] Among the (B) phosphate ester compounds mentioned above, condensed phosphate esters are preferred from the viewpoint of flame retardancy and bleed-out resistance. Examples of condensed phosphate esters include resorcinol diphenyl phosphate, hydroquinone diphenyl phosphate, bisphenol A diphenyl phosphate, and biphenyl diphenyl phosphate. Commercially available products include PX-202, CR-741, PX-200, PX-201 manufactured by Daihachi Chemical Industry Co., Ltd., and FP-500, FP-600, FP-700, and PFR manufactured by Adeka Corporation.

[0030] The amount of the (B) phosphate ester compound used in the present invention is 10 to 120 parts by mass per 100 parts by mass of the (A) polybutylene terephthalate resin, from the viewpoint of balancing flame retardancy and bleed-out resistance. If the amount of component (B) is less than 10 parts by mass, flame retardancy and tracking resistance will decrease. Preferably, it is 20 parts by mass or more, more preferably 30 parts by mass or more, even more preferably 40 parts by mass or more, and particularly preferably 60 parts by mass or more. On the other hand, if the amount of component (B) exceeds 120 parts by mass, bleed-out resistance and weld strength will decrease. Preferably, it is 110 parts by mass or less, more preferably 100 parts by mass or less, and even more preferably 90 parts by mass or less.

[0031] In the present invention, it is preferable to further incorporate (C) styrene resin (hereinafter sometimes abbreviated as (C) component).

[0032] In the present invention, (C) styrene-based resin is a thermoplastic resin obtained by polymerizing a monomer containing styrene, and specifically includes polystyrene, styrene / acrylonitrile copolymer, and rubber-modified styrene-based resin. Specific examples of rubber-modified styrene-based resins include, for example, high-impact polystyrene (HIPS), ABS resin (acrylonitrile / butadiene / styrene copolymer), AAS resin (acrylonitrile / acrylic / styrene copolymer), and AES resin (acrylonitrile / ethylene propylene / styrene copolymer).

[0033] The (C) styrene-based resin of the present invention is preferably epoxy-modified by graft polymerization or copolymerization with an epoxy group-containing monomer such as glycidyl acrylate, from the viewpoint of the dispersibility of the island phase of component (D). It may also have a syndiotactic structure formed by polymerization using a metallocene catalyst.

[0034] Furthermore, the amount of component (C) is preferably 1 to 40 parts by mass per 100 parts by mass of polybutylene terephthalate resin (A). If the amount of component (C) is less than 1 part by mass, the bleed-out resistance may decrease. Preferably, it is 3 parts by mass or more, more preferably 5 parts by mass or more, and particularly preferably 10 parts by mass or more. On the other hand, if the amount of component (C) exceeds 40 parts by mass, the flame retardancy tends to decrease. Preferably, it is 35 parts by mass or less, more preferably 30 parts by mass or less, and particularly preferably 25 parts by mass or less.

[0035] In the present invention, (D) flame-retardant resin refers to a thermoplastic resin that is flame-retardant even without the addition of a flame retardant, and it is preferable to use a resin in which the mass loss from room temperature to 600°C when heated in air at a heating rate of 40°C / min is 70% by mass or less. From the viewpoint of flame retardancy, the upper limit of the mass loss is preferably 60% by mass or less, and more preferably 50% by mass or less. The lower limit of the mass loss is 0% by mass.

[0036] The aforementioned mass loss can be calculated using a calorimeter (Perkin Elmer, TGA-7) to measure the mass when the temperature is raised from 30°C at room temperature to 600°C at a heating rate of 40°C / min while supplying air at a flow rate of 40 mL / min, and then calculated using the formula: {(Mass before heating (at room temperature) - Mass after heating (at 600°C)) / Mass before heating × 100}.

[0037] Examples of the (D) flame-retardant resin of the present invention include polyarylene ether ketone, polyetherimide resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, crystalline polyester resin, polyarylate resin, and phenolic resin, and polyphenylene sulfide resin is preferred from the viewpoint of efficiently forming island phases of the (D) component.

[0038] In the present invention, the polyphenylene sulfide resin is a polymer or copolymer having repeating units represented by the following general formula (1).

[0039] [ka]

[0040] A polymer or copolymer containing, preferably 70 mol% or more, and more preferably 90 mol% or more, of the repeating units represented by the above general formula (1) is preferred from the viewpoint of heat resistance. Furthermore, a polyphenylene sulfide resin can be composed of repeating units having the structure described in the following general formula (2) for less than 30 mol% of its repeating units.

[0041] [ka]

[0042] The melt viscosity of polyphenylene sulfide resin is not particularly limited as long as melt mixing is possible, but is typically 5 to 2000 Pa·s (at 320°C and a shear rate of 10 sec). -1 The following will be used.

[0043] Polyphenylene sulfide resins can be manufactured by known methods. Commercially available products include, for example, "Torelina" (registered trademark) (manufactured by Toray Industries, Inc.) and PPS (manufactured by DIC Corporation).

[0044] Furthermore, the amount of component (D) blended is 1 to 20 parts by mass per 100 parts by mass of polybutylene terephthalate resin (A). If the amount of component (D) blended is less than 1 part by mass, the flame retardancy decreases. More preferably, it is 3 parts by mass or more, more preferably 5 parts by mass or more, and particularly preferably 6 parts by mass or more. On the other hand, if the amount of component (D) blended exceeds 20 parts by mass, the tracking resistance decreases. Preferably, it is 18 parts by mass or less, more preferably 16 parts by mass or less, and particularly preferably 14 parts by mass or less.

[0045] The polybutylene terephthalate resin composition of the present invention has a phase structure in which the average diameter of the island phase of the flame-retardant resin (D) is 0.05 to 5.0 μm within the sea phase of the polybutylene terephthalate resin (A).

[0046] The average diameter of the island phase of component (D) in the resin composition of the present invention can be determined by electron microscopy observation using the following method. Under general molding conditions, the phase separation structure and the size of each phase of the resin composition do not change, so in the present invention, the phase separation structure is observed using a test piece obtained by molding the resin composition. First, the center of the cross-sectional direction of a strip-shaped test piece (length 125 mm × width 13 mm × thickness 1.6 mm) obtained by injection molding is cut into a 1 to 1.6 mm square to obtain a sample for electron microscopy. After depositing platinum-palladium onto the sample for electron microscopy by sputtering, an elemental mapping image is obtained by energy dispersion using a field emission scanning electron microscope (FE-SEM). If necessary to clearly observe components (A), (C), and (D), the sample may be stained with a dye such as ruthenium oxide depending on the resin used, and observed using the elements contained in the dye. For example, if styrene resin is selected for component (C) and polyphenylene sulfide resin for component (D), the components can be distinguished by mapping each component with the elements they contain, such as mapping oxygen atoms for component (A), carbon atoms for component (C), and sulfur atoms for component (D), and then observing the island phases of components (C) and (D) while overlaying them with the SEM image. Furthermore, if it is difficult to distinguish between components (A) and (D), the components can be distinguished by staining component (A) with ruthenium oxide.

[0047] In this invention, if an island phase of component (D) is formed, the magnification is adjusted so that 100 to less than 200 island phases are present in a square electron microscope image in order to determine its average diameter. At this magnification, 20 island phases are selected from the largest to smallest in the observed image, and the major and minor axes are measured for each island phase. The average of these major and minor axes is taken as the diameter of each island phase, and the average of the diameters of all measured island phases is taken as the diameter of the island phase. The major and minor axes of the island phase refer to the longest and shortest diameters, respectively. The value was the average of the measurements taken from three test specimens.

[0048] The average diameter of the island phase of component (D) in the resin composition of the present invention is 0.05 to 5.0 μm. If the average diameter of the island phase is less than 0.05 μm, flame retardancy and bleed-out resistance decrease. Preferably, it is 0.1 μm or more, more preferably 0.2 μm or more, and particularly preferably 0.3 μm or more. On the other hand, if the average diameter of the island phase exceeds 5 μm, tracking resistance and weld strength decrease. Preferably, it is 4.0 μm or less, more preferably 3.0 μm or less, and particularly preferably 2.0 μm or less.

[0049] In the present invention, the method for making the island phase of component (D) have a specific average diameter is not limited as long as such a resin composition can be obtained. For example, one method is to select a polyphenylene sulfide resin as component (D), increase the cylinder temperature, screw kneading count, and screw rotation speed so that the resin temperature during melt kneading of the composition is between 285°C and 335°C, and then set the blending ratio of component (C) to component (D) in the range of 0.5 to 4.0. Alternatively, it is also preferable to select a polyphenylene sulfide resin as component (D), increase the cylinder temperature, screw kneading count, and screw rotation speed so that the resin temperature during melt kneading of the composition is between 285°C and 335°C, and then set the blending amount of component (B) in the range of 80 to 120 parts by mass. These conditions vary depending on the combination of resins used and cannot be generalized, but the conditions can be set by conducting simple preliminary experiments.

[0050] In the present invention, it is preferable to further incorporate component (C) so that component (C) becomes unevenly distributed at the interface of the island phase of component (D), forming a composite island phase in which the island phase of component (D) is dispersed within the island phase of component (C), thereby further improving flame retardancy and tracking resistance.

[0051] In the resin composition of the present invention, the average diameter of the composite island phase is preferably 1 to 20 μm. If the average diameter of the composite island phase is 1 μm or more, flame retardancy and bleed-out resistance are further improved. Preferably, it is 2 μm or more, more preferably 3 μm or more, and particularly preferably 4 μm or more. On the other hand, if the average diameter of the composite island phase is 20 μm or less, tracking resistance and weld strength are further improved. Preferably, it is 18 μm or less, more preferably 16 μm or less, and particularly preferably 14 μm or less. The average diameter of the composite island phase can be determined by determining the average diameter of the island phase of component (C), which includes the island phase of component (D), in the same way as determining the average diameter of the island phase of component (D).

[0052] Therefore, from the viewpoint of forming a composite island phase, a preferred range can be set for the ratio (C) / (D) of [(A) polybutylene terephthalate resin (C) blended with 100 parts by mass of polybutylene terephthalate resin (A)] to [(D) flame retardant resin (D) blended with 100 parts by mass of polybutylene terephthalate resin (A)]. The lower limit of (C) / (D) is preferably 0.5 or more, more preferably 0.8 or more, even more preferably 1.1 or more, and particularly preferably 1.5 or more. On the other hand, the upper limit of (C) / (D) is preferably 4.0 or less, more preferably 3.6 or less, even more preferably 3.0 or less, and particularly preferably 2.5 or less, from the viewpoint of setting the upper limit of the average diameter of the island phase of component (D) to a preferred range.

[0053] In the present invention, the polybutylene terephthalate resin composition preferably contains 10 to 150 parts by mass of (E) a nitrogen-containing heterocyclic compound having a triazine skeleton (hereinafter sometimes abbreviated as component (E)) per 100 parts by mass of (A) polybutylene terephthalate resin. The inclusion of component (E) is preferable because it improves the flame retardancy and bleed-out resistance of the polybutylene terephthalate resin composition.

[0054] Examples of nitrogen-containing heterocyclic compounds having a (E) triazine skeleton used in the present invention include melamine, benzoguanamine, cyanuric acid, melamine cyanurate, melamine isocyanurate, triphenyltriazine, ammeline, ammelido, thiocyanuric acid, diaminomethyltriazine, and melamine polyphosphate, with melamine cyanurate, melamine isocyanurate, and melamine polyphosphate being preferred.

[0055] The melamine cyanurate or melamine isocyanurate is preferably an adduct of a triazine compound and cyanuric acid or isocyanuric acid, typically having a 1:1 molar ratio, and sometimes a 1:2 molar ratio. These are produced by known methods, but for example, a mixture of melamine and cyanuric acid or isocyanuric acid is made into an aqueous slurry, thoroughly mixed to form fine particles of salts of both, and then filtered and dried to generally obtain a powder. The salt does not need to be completely pure, and some unreacted melamine, cyanuric acid, or isocyanuric acid may remain. If dispersibility is poor, dispersants such as tris(β-hydroxyethyl) isocyanurate or known surface treatment agents such as polyvinyl alcohol and metal oxides such as silica may be used in combination. The average diameter of the melamine cyanurate or melamine isocyanurate before and after being blended into the resin is preferably 0.1 to 100 μm from the viewpoint of flame retardancy, mechanical strength, and surface properties of the molded article. Here, the average diameter is the average diameter measured at the cumulative distribution 50% particle size using the laser microsizing method. As commercially available melamine cyanurate or melamine isocyanurate, Nissan Chemical Corporation's MC-4000, MC-4500, and MC-6000 are preferably used.

[0056] Furthermore, the amount of nitrogen-containing heterocyclic compound having a triazine skeleton (E) is preferably 10 to 150 parts by mass per 100 parts by mass of polybutylene terephthalate resin (A), from the viewpoint of balancing flame retardancy and mechanical properties. An amount of component (E) of 10 parts by mass or more is preferable because it has excellent flame retardancy and bleed-out resistance, more preferably 50 parts by mass or more, and even more preferably 70 parts by mass or more. On the other hand, an amount of component (E) of 150 parts by mass or less is preferable because it has excellent weld strength, more preferably 130 parts by mass or less, and even more preferably 110 parts by mass or less.

[0057] In the present invention, the polybutylene terephthalate resin composition preferably contains 1 to 40 parts by mass of (F) core-shell rubber (hereinafter sometimes abbreviated as component (F)) per 100 parts by mass of (A) polybutylene terephthalate resin.

[0058] (F) Core-shell rubber is a polymer having a structure known as a core-shell type, consisting of an innermost layer (core layer) and one or more layers (shell layers) covering it, and adjacent layers being composed of different polymers, and having at least one rubber layer inside.

[0059] The number of layers constituting the (F) core shell rubber of the present invention is not particularly limited and may be two or more layers, or it may be three or more layers or four or more layers.

[0060] In the (F) core-shell rubber of the present invention, the type of rubber layer is not particularly limited and can be any polymer component having rubber elasticity. For example, rubber composed of polymers of acrylic components, silicone components, styrene components, nitrile components, conjugated diene components, urethane components, or ethylene propylene components is an example. Preferred rubbers are, for example, rubber composed of polymers of acrylic components such as ethyl acrylate units or butyl acrylate units, silicone components such as dimethylsiloxane units or phenylmethylsiloxane units, styrene components such as styrene units or α-methylstyrene units, nitrile components such as acrylonitrile units or methacrylonitrile units, and conjugated diene components such as butanediene units or isoprene units. Furthermore, rubbers composed of copolymers of two or more of these components are also preferred. Examples include: (1) rubber composed of a copolymer of acrylic components such as ethyl acrylate units and butyl acrylate units and silicone components such as dimethylsiloxane units and phenylmethylsiloxane units; (2) rubber composed of a copolymer of acrylic components such as ethyl acrylate units and butyl acrylate units and styrene components such as styrene units and α-methylstyrene units; (3) rubber composed of a copolymer of acrylic components such as ethyl acrylate units and butyl acrylate units and conjugated diene components such as butanediene units and isoprene units; and (4) rubber composed of a copolymer of acrylic components such as ethyl acrylate units and butyl acrylate units, silicone components such as dimethylsiloxane units and phenylmethylsiloxane units, and styrene components such as styrene units and α-methylstyrene units. In addition to these components, rubbers obtained by copolymerizing and crosslinking crosslinkable components such as divinylbenzene units, allyl acrylate units, and butylene glycol diacrylate units are also preferred. In this invention, any material that falls under either (C) styrene resin or (F) core-shell rubber is included in (F) core-shell rubber.

[0061] In the (F) core-shell rubber of the present invention, the type of layer other than the rubber layer is not particularly limited as long as it is composed of a thermoplastic polymer component, but it is preferable that the polymer component has a higher glass transition temperature than the rubber layer. Examples of thermoplastic polymers include polymers containing at least one unit selected from unsaturated carboxylate alkyl ester units, unsaturated glycidyl group-containing units, unsaturated dicarboxylic acid anhydride units, aliphatic vinyl units, aromatic vinyl units, vinyl cyanide units, maleimide units, unsaturated dicarboxylic acid units, and other vinyl units. Among these, polymers containing at least one unit selected from unsaturated carboxylate alkyl ester units, unsaturated glycidyl group-containing units, and unsaturated dicarboxylic acid anhydride units are preferred, and polymers containing at least one unit selected from unsaturated glycidyl group-containing units and unsaturated dicarboxylic acid anhydride units are even more preferred.

[0062] The above unsaturated carboxylate alkyl ester units are not particularly limited, but alkyl (meth)acrylates are preferably used. Specifically, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, stearyl (meth)acrylate, octadecyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, chloromethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, and (meth)acrylate. Examples include 3-hydroxypropyl lylate, 2,3,4,5,6-pentahydroxyhexyl (meth)acrylate, 2,3,4,5-tetrahydroxypentyl (meth)acrylate, aminoethyl acrylate, propylaminoethyl acrylate, dimethylaminoethyl methacrylate, ethylaminopropyl methacrylate, phenylaminoethyl methacrylate, and cyclohexylaminoethyl methacrylate. From the viewpoint of significantly improving impact resistance, methyl (meth)acrylate is preferably used. These units can be used individually or in combination of two or more.

[0063] The above-mentioned unsaturated glycidyl group-containing units are not particularly limited and include glycidyl (meth)acrylate, glycidyl itaconic acid, diglycidyl itaconic acid, allyl glycidyl ether, styrene-4-glycidyl ether, and 4-glycidylstyrene. From the viewpoint of having a significant effect in improving impact resistance, glycidyl (meth)acrylate is preferably used. These units can be used individually or in combination of two or more.

[0064] Examples of the unsaturated dicarboxylic acid anhydride units mentioned above include maleic anhydride, itaconic anhydride, glutaconic anhydride, citraconic anhydride, and aconitic anhydride. Maleic anhydride is preferred because it has a significant effect in improving impact resistance. These units can be used individually or in combination of two or more.

[0065] Furthermore, the above aliphatic vinyl units include ethylene, propylene, and butadiene, the above aromatic vinyl units include styrene, α-methylstyrene, 1-vinylnaphthalene, 4-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene, and halogenated styrene, the above vinyl cyanide units include acrylonitrile, methacrylonitrile, and ethacrylonitrile, and the above maleimide units include maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-cyclohexylmaleimide, N Examples of unsaturated dicarboxylic acid units include phenylmaleimide, maleic acid, maleic acid monoethyl ester, itaconic acid, and phthalic acid, and examples of other vinyl units include acrylamide, methacrylamide, N-methylacrylamide, butoxymethylacrylamide, N-propylmethacrylamide, N-vinyldiethylamine, N-acetylvinylamine, allylamine, methallylamine, N-methylallylamine, p-aminostyrene, 2-isopropenyl-oxazoline, 2-vinyl-oxazoline, 2-acroyl-oxazoline, and 2-styryl-oxazoline. These units can be used individually or in combination of two or more.

[0066] In the (F) core-shell rubber of the present invention, the type of outermost layer is not particularly limited, and includes at least one selected from polymers containing unsaturated carboxylate alkyl ester units, unsaturated glycidyl group-containing units, aliphatic vinyl units, aromatic vinyl units, vinyl cyanide units, maleimide units, unsaturated dicarboxylic acid units, unsaturated dicarboxylic acid anhydride units, and other vinyl units. Among these, at least one selected from polymers containing unsaturated carboxylate alkyl ester units, aliphatic vinyl units, aromatic vinyl units, and vinyl cyanide units is preferred, and polymers containing aromatic vinyl units and vinyl cyanide units are even more preferred.

[0067] The unsaturated carboxylate alkyl ester units referred to herein are not particularly limited, but alkyl (meth)acrylates are preferred, and methyl (meth)acrylates are even more preferred. Furthermore, styrene is more preferred as the aromatic vinyl unit, and acrylonitrile is more preferred as the vinyl cyanide unit.

[0068] Preferred examples of the (F) core-shell rubber of the present invention include those in which the core layer is a dimethylsiloxane / butyl acrylate polymer and the outermost layer is a methyl methacrylate polymer, those in which the core layer is a dimethylsiloxane / butyl acrylate polymer and the outermost layer is a styrene / acrylonitrile polymer, those in which the core layer is a butanediene / styrene polymer and the outermost layer is a methyl methacrylate polymer, and those in which the core layer is a butyl acrylate polymer and the outermost layer is a methyl methacrylate polymer, with the case in which the core layer is a dimethylsiloxane / butyl acrylate polymer and the outermost layer is a styrene / acrylonitrile polymer being particularly preferred.

[0069] The particle size of the (F) core-shell rubber of the present invention is not particularly limited, but is preferably 0.01 μm or more and 100 μm or less, more preferably 0.02 μm or more and 10 μm or less, and most preferably 0.05 μm or more and 1 μm or less.

[0070] In the (F) core-shell rubber of the present invention, the mass ratio of the core to the shell is not particularly limited, but it is preferable that the core layer is 10 parts by mass or more and 90 parts by mass or less, and more preferably 30 parts by mass or more and 80 parts by mass or less, relative to the entire core-shell rubber.

[0071] The (F) core shell rubber of the present invention may be a commercially available product that satisfies the above-mentioned conditions, or it may be manufactured by a known method and used.

[0072] Examples of commercially available core-shell rubbers include "Metablen" from Mitsubishi Chemical Corporation, "Kaneace" from Kaneka Corporation, "Paraloid" from Dow Corporation, "Stafiloid" from Aica Industrial Co., Ltd., and "Parapet SA" from Kuraray Co., Ltd., which can be used individually or in combination of two or more types.

[0073] Furthermore, the amount of component (F) is preferably 1 to 40 parts by mass per 100 parts by mass of polybutylene terephthalate resin (A). If the amount of component (F) is less than 1 part by mass, the bleed-out resistance decreases. Preferably, it is 3 parts by mass or more, more preferably 5 parts by mass or more, and particularly preferably 10 parts by mass or more. On the other hand, if the amount of component (F) exceeds 40 parts by mass, the flame retardancy decreases. Preferably, it is 35 parts by mass or less, more preferably 30 parts by mass or less, and particularly preferably 25 parts by mass or less.

[0074] The polybutylene terephthalate resin composition of the present invention preferably further contains (G) a hindered amine compound to improve flame retardancy, bleed-out resistance, weld strength, and stability of molding pressure during injection molding. The hindered amine compound is a compound having a structure in which at least one 2,2,6,6-tetramethylpiperidine derivative is present in the molecule.

[0075] Specific examples of hindered amine compounds used in the present invention include 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis-(2,2,6,6-tetramethyl-4-piperidyl)adipate, bis-(2,2,6,6-tetramethyl-4-piperidyl)sverate, bis-(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis-(2,2,6,6-tetramethyl-4-piperidyl)phthalate, bis-(2,2,6,6-tetramethyl-4-piperidyl)terephthalate, and bis-(1,2,2,6,6-pentamethyl-4-piperidine). Lysyl) sebacate, bis-(1,2,2,6,6-pentamethyl-4-piperidyl) terephthalate, N,N'-bis-(2,2,6,6-tetramethyl-4-piperidyl) isophthalamide, N,N'-bis-(2,2,6,6-tetramethyl-4-piperidyl) adipamide, bis-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-butyl(3,5-di-t-butyl-4-hydroxybenzyl) malonate, bis-(2,2,6,6-tetramethyl-4-piperidyl)-n-butyl(3,5-di-t-butyl-4-hydroxybenzyl) Malonate, tetra-(2,2,6,6-tetramethyl-4-piperidyl) ester of butanetetracarboxylic acid, 1-[2-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]2,2,6,6-tetramethylpiperidine, poly[[6-(1,1,3,3-tetramethylbutyl)imino-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethylpiperidyl)imino]hexamethylene[(2,2,6,6 -Tetramethyl-4-piperidyl)imino]], tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate, dimethyl-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine succinate, 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-4-piperidinol and β,β,β',β'-tetramethyl-3,9-(2,4,Examples include condensates of 8,10-tetraoxaspiro[5,5]undecane)diethanol, and condensates of 1,2,3,4-butanetetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol, and β,β,β',β'-tetramethyl-3,9-(2,4,8,10-tetraoxaspiro[5,5]undecane)diethanol.

[0076] The amount of the (G) hindered amine compound used in the present invention is preferably 0.3 to 3.0 parts by mass per 100 parts by mass of (A) polybutylene terephthalate resin, from the viewpoint of flame retardancy, bleed-out resistance, weld strength, and stability of molding pressure during injection molding. An amount of 0.3 parts by mass or more of component (G) is preferable because it provides excellent bleed-out resistance and weld strength, more preferably 0.5 parts by mass or more, even more preferably 0.8 parts by mass or more, and particularly preferably 1.0 part by mass or more. On the other hand, an amount of 3.0 parts by mass or less of component (G) is preferable because it suppresses the decomposition of the (A) polybutylene terephthalate resin by the amine component, resulting in excellent flame retardancy and weld strength, more preferably 2.5 parts by mass or less, even more preferably 2.0 parts by mass or less, and particularly preferably 1.5 parts by mass or less.

[0077] The polybutylene terephthalate resin composition of the present invention preferably has a ratio of parts by mass of the (B) phosphate ester compound to parts by mass of the (G) hindered amine compound ([parts by mass of component (B) per 100 parts by mass of component (A)] / [parts by mass of component (G) per 100 parts by mass of component (A)]) (hereinafter sometimes abbreviated as (B) / (G)) of 5 to 50. Controlling the ratio of the amounts of component (B) and component (G) within the above range is preferable because it provides excellent dispersibility of component (B) in the (A) polybutylene terephthalate resin composition, efficiently reacts with component (G), and provides superior flame retardancy, bleed-out resistance, weld strength, and stability of molding pressure during injection molding at a higher level. From the viewpoint of flame retardancy and mechanical strength, (B) / (G) is more preferably 6 or higher, and even more preferably 8 or higher. On the other hand, from the viewpoint of bleed-out resistance, weld strength, and stability of molding pressure during injection molding, a value of 40 or less is more preferable, and 30 or less is even more preferable.

[0078] The polybutylene terephthalate resin composition of the present invention preferably further contains (H) fibrous reinforcing material (hereinafter sometimes abbreviated as (H) component). The (H) fibrous reinforcing material can further improve mechanical strength and heat resistance.

[0079] Specific examples of the (H) fibrous reinforcing material mentioned above include glass fibers, aramid fibers, and carbon fibers. The glass fibers used are preferably chopped strand type or roving type glass fibers, and are treated with a sizing agent containing a silane coupling agent such as an aminosilane compound or epoxysilane compound, and / or a copolymer of urethane, acrylic acid such as an acrylic acid / styrene copolymer, a copolymer of maleic anhydride such as a methyl acrylate / methyl methacrylate / maleic anhydride copolymer, vinyl acetate, one or more epoxy compounds such as bisphenol A diglycidyl ether or novolac epoxy compounds. Glass fibers treated with a copolymer of maleic anhydride or a sizing agent containing an epoxy compound are even more preferable because they can further improve mechanical properties and hydrolysis resistance during high-temperature molding. The silane coupling agent and / or sizing agent may be mixed into an emulsion liquid before use. Furthermore, the fiber diameter of the glass fibers is usually preferably in the range of 1 to 30 μm. From the viewpoint of dispersibility of glass fibers in the polybutylene terephthalate resin composition, the lower limit is preferably 5 μm, and from the viewpoint of mechanical strength, the upper limit is preferably 15 μm. Furthermore, although the fiber cross-section is usually circular, fibrous reinforcing materials with arbitrary cross-sections, such as elliptical glass fibers with arbitrary aspect ratios, flattened glass fibers, and cocoon-shaped glass fibers, can also be used, which has the advantage of improving fluidity during injection molding and producing molded products with less warping.

[0080] Furthermore, the amount of (H) fibrous reinforcing material added is preferably 1 to 170 parts by mass per 100 parts by mass of (A) polybutylene terephthalate resin. Adding 1 part by mass or more of (H) fibrous reinforcing material can further improve mechanical strength, heat resistance, and weld strength. More preferably 10 parts by mass or more, and even more preferably 30 parts by mass or more. On the other hand, adding 170 parts by mass or less of (H) fibrous reinforcing material can further improve mechanical strength and fluidity. More preferably 150 parts by mass or less, and even more preferably 130 parts by mass or less.

[0081] The polybutylene terephthalate resin composition of the present invention preferably contains a chelating agent to further improve hydrolysis resistance. The chelating agent can be any compound that can react and chelate the carboxyl group ends of the (A) polybutylene terephthalate resin, such as epoxy compounds or carbodiimide compounds.

[0082] The polybutylene terephthalate resin composition of the present invention may contain one or more optional additives such as antioxidants, thermal stabilizers, ultraviolet absorbers, light stabilizers, plasticizers, mold release agents, antistatic agents, drip inhibitors, carbon black, titanium dioxide, and various colored pigments and dyes, as well as one or more inorganic fillers other than component (H), to the extent that the objectives of the present invention are not impaired.

[0083] The polybutylene terephthalate resin composition of the present invention may contain thermoplastic resins other than component (A) to the extent that the objectives of the present invention are not impaired, thereby improving moldability, dimensional accuracy, molding shrinkage, and toughness. Examples of thermoplastic resins other than component (A) include polyolefin resins, polyamide resins, polyacetal resins, polyurethane resins, aliphatic polyketone resins, thermoplastic starch resins, poly-4-methylpentene-1, cellulose acetate resins, and polyvinyl alcohol resins. When thermoplastic resins other than component (A) are incorporated, it is preferable that component (A) accounts for the largest proportion among the thermoplastic resin types incorporated into the polybutylene terephthalate resin composition of the present invention.

[0084] In the polybutylene terephthalate resin composition of the present invention, there are no restrictions on the amount of the above-mentioned components to be blended, as long as the objective of the present invention is not impaired. However, it has been found that the properties can be further improved by limiting the amount of specific components. Four components for which it is preferable to limit the amount of blending are described below.

[0085] Firstly, in order to prevent a decrease in the crystallinity of (A) polybutylene terephthalate resin and improve bleed-out resistance, it is preferable that at least one selected from polyethylene terephthalate resin, polyetherimide resin, and polycarbonate resin be in amounts of less than 5 parts by mass, more preferably less than 3 parts by mass, and particularly preferably less than 1 part by mass, per 100 parts by mass of (A) polybutylene terephthalate resin.

[0086] Secondly, in order to form the island phase of component (D) with a suitable average diameter and improve tracking resistance, it is preferable that the amount of polyphenylene ether resin is less than 5 parts by mass, more preferably less than 3 parts by mass, and particularly preferable less than 1 part by mass per 100 parts by mass of polybutylene terephthalate resin (A).

[0087] Thirdly, in terms of reducing the PFAS content and improving weld strength, it is preferable that the content of fluororesin, which is generally blended as an anti-dripping agent, is less than 0.5 parts by mass, more preferably less than 0.3 parts by mass, and particularly preferable less than 0.1 parts by mass per 100 parts by mass of (A) polybutylene terephthalate resin.

[0088] The aforementioned fluororesins are resins containing fluorine in their molecular structure and are compounds subject to PFAS regulations. Specifically, examples include polytetrafluoroethylene, polyhexafluoropropylene, (tetrafluoroethylene / hexafluoropropylene) copolymers, (tetrafluoroethylene / perfluoroalkyl vinyl ether) copolymers, (tetrafluoroethylene / ethylene) copolymers, (hexafluoropropylene / propylene) copolymers, polyvinylidene fluoride, and (vinylidene fluoride / ethylene) copolymers. Among these, polytetrafluoroethylene, (tetrafluoroethylene / perfluoroalkyl vinyl ether) copolymers, (tetrafluoroethylene / hexafluoropropylene) copolymers, (tetrafluoroethylene / ethylene) copolymers, and polyvinylidene fluoride are particularly noteworthy.

[0089] Fourthly, in terms of improving bleed-out resistance, it is preferable that the amount of at least one phosphinate or phosphazene compound selected from phosphinates and diphosphinates, which are commonly used as flame retardants, be less than 5 parts by mass, more preferably less than 3 parts by mass, and particularly preferably less than 1 part by mass, per 100 parts by mass of (A) polybutylene terephthalate resin.

[0090] The polybutylene terephthalate resin composition of the present invention can be obtained, for example, by melt-kneading components (A) to (D) and, if necessary, other components.

[0091] Examples of melt-mixing methods include pre-mixing components (A) to (D), other components as needed, and various additives, and supplying them to an extruder for thorough melt-mixing, or supplying predetermined amounts of each component to an extruder using a weight feeder or similar quantitative feeder for thorough melt-mixing.

[0092] Examples of the above pre-mixing include dry blending and mixing using mechanical mixing equipment such as tumblers, ribbon mixers, and Henschel mixers. In addition, (H) fibrous reinforcing materials and inorganic fillers other than fibrous reinforcing materials may be added by installing a side feeder between the loading and vent sections of a multi-screw extruder such as a twin-screw extruder. In the case of liquid additives, methods such as installing a liquid addition nozzle between the loading and vent sections of a multi-screw extruder such as a twin-screw extruder and adding it using a plunger pump, or supplying it from the loading section using a metering pump may be used.

[0093] The polybutylene terephthalate resin composition of the present invention is preferably pelletized before molding. Examples of pelletizing methods include using a single-screw extruder, twin-screw extruder, tri-screw extruder, conical extruder, or kneader-type mixer equipped with "Unimelt" or "Dalmege" type screws to extrude the material in strands, which are then cut with a strand cutter.

[0094] The polybutylene terephthalate resin composition of the present invention is preferably kneaded by a twin-screw extruder from the viewpoint of productivity in order to uniformly mix components (A) to (D). For the twin-screw extruder, it is preferable to have one or more kneading sections, and more preferably two or more, in order to improve the dispersibility of the flame retardant. The locations of the kneading sections are, for example, when component (H) is added from a side feeder, it is preferable to have one or more kneading sections upstream of the side feeder to promote the plasticization and dispersion of components (A) to (D), and one or more kneading sections downstream of the side feeder to disperse component (H) in the resin composition while suppressing breakage, for a total of two or more kneading sections.

[0095] In order to form a composite island phase with a specific average diameter, the polybutylene terephthalate resin composition of the present invention allows for the setting of a preferred range for the resin temperature during kneading of components (A) to (D). The lower limit of the resin temperature during kneading is preferably 285°C or higher, more preferably 288°C or higher, and particularly preferably 290°C or higher, in order to finely disperse and composite components (C) and (D). On the other hand, the upper limit of the resin temperature during kneading is preferably 335°C or lower, more preferably 320°C or lower, and particularly preferably 310°C or lower, in order to suppress the decomposition of component (A) and improve its strength. The resin temperature during kneading can be controlled by the processing rate of the resin composition per unit of time, the temperature setting of the heating section of the kneader, and the rotation speed of the screw and stirring blades. The resin temperature can be measured by directly contacting a thermocouple with the molten resin composition in the hole when the resin composition is discharged from the hole in the discharge section of the extruder.

[0096] By melt-molding the polybutylene terephthalate resin composition of the present invention, films, fibers, and molded articles of various other shapes can be obtained. Examples of melt-molding methods include injection molding, extrusion molding, and blow molding, with injection molding being particularly preferred.

[0097] In addition to conventional injection molding methods, other known injection molding methods include gas-assisted molding, two-color molding, sandwich molding, in-mold molding, insert molding, and injection press molding, and any of these molding methods can be applied.

[0098] The molded articles of the present invention can be used as molded parts for mechanical mechanisms, electrical components, electronic components, and automotive parts, taking advantage of their excellent flame retardancy, tracking resistance, bleed-out resistance, and weld strength. Furthermore, due to their excellent weld strength, they can be used for small, thin-walled molded articles and molded articles containing metal inserts. In addition, because the molded articles of the present invention have excellent flame retardancy, tracking resistance, and bleed-out resistance, they are particularly useful for electrical and electronic components for automobiles.

[0099] Specific examples of mechanical components, electrical components, electronic components, and automotive components include circuit breakers, electromagnetic switches, focus cases, flyback transformers, molded parts for fusers in photocopiers and printers, housings for general household appliances and office automation equipment, variable capacitor case components, various terminal boards, printed circuit boards, housings, terminal blocks, coil bobbins, connectors, relays, disk drive chassis, transformers, switch components, outlet components, motor components, sockets, plugs, capacitors, various cases, resistors, electrical and electronic components incorporating metal terminals and wires, computer-related components, audio components such as sound components, lighting components, telegraph equipment-related components, telephone equipment-related components, air conditioner components, home appliance components such as VTRs and televisions, photocopier components, facsimile components, optical equipment components, automotive ignition system components, automotive charging system components, automotive connectors, automotive high-voltage connectors, insulating materials such as busbars, and various automotive electrical components.

[0100] The molded articles of the present invention are useful for high-voltage insulating components because they can achieve both high flame retardancy and tracking resistance. In particular, they are especially useful in high-voltage connectors, power module cases, and busbars, particularly when used in high-voltage applications of 400V or higher, as they allow for greater design flexibility and miniaturization. [Examples]

[0101] Next, the effects of the polybutylene terephthalate resin composition of the present invention will be specifically explained with reference to examples. The raw materials used in the examples and comparative examples are shown below. Here, % and parts all represent mass%, and " / " in the resin names below indicates copolymerization.

[0102] (A) Polybutylene terephthalate resin <a-1>Polybutylene terephthalate resin: A polybutylene terephthalate resin manufactured by Toray Industries, Inc. was used, with a carboxyl group content of 30 eq / t and an intrinsic viscosity of 0.80 dl / g measured at 25°C using o-chlorophenol as a solvent.

[0103] (B) Phosphate ester compounds <b-1>Resorcinol bis(di-2,6-xylyl phosphate): PX-200 manufactured by Daihachi Chemical Industry Co., Ltd. was used.

[0104] (C) Styrene resin <c-1>Polystyrene resin: GPPS, HF77 manufactured by PS Japan Co., Ltd. was used. <c-2>Styrene / acrylonitrile (74 / 26% by mass) copolymer: AS resin manufactured by Toray Industries, Inc. was used. <c-3>Styrene / acrylonitrile / glycidyl methacrylate (74 / 25.5 / 0.5% by mass) copolymer: Epoxy-modified AS resin manufactured by Toray Industries, Inc. was used.

[0105] (D) Flame-retardant resin <d-1>Liquid crystal polyester resin: Liquid crystal polyester resin manufactured by the following method <d-1>I used it.

[0106] In a 5L reaction vessel equipped with a stirring blade and a distillation tube, 994 parts by mass of p-hydroxybenzoic acid, 126 parts by mass of 4,4'-dihydroxybiphenyl, 112 parts by mass of terephthalic acid, 216 parts by mass of polyethylene terephthalate with an intrinsic viscosity of approximately 0.6 dl / g, and 960 parts by mass of acetic anhydride (1.10 equivalents of the total phenolic hydroxyl groups) were charged. The mixture was reacted at 145°C for 1 hour with stirring under a nitrogen gas atmosphere, and then the temperature was raised from 145°C to 320°C over 4 hours. The polymerization temperature was then maintained at 320°C, and the pressure was reduced to 1.0 mmHg (133 Pa) over 1.0 hour. The reaction continued until the stirring torque reached 20 kg·cm, at which point polymerization was completed. Next, the polymer was discharged into strands through a nozzle with a 10 mm diameter circular outlet, and then pelletized using a cutter to produce a liquid crystalline polyester resin. <d-1>This liquid crystal polyester resin was obtained. <d-1>Compositional analysis revealed that the proportion of structural units derived from p-hydroxybenzoic acid was 66.7 mol%, those derived from 4,4'-dihydroxybiphenyl was 6.3 mol%, those derived from polyethylene terephthalate were 10.4 mol%, and those derived from terephthalic acid were 16.7 mol%. It was a liquid crystal polyester resin with a melting point of 313°C and a mass loss of 61% by mass when heated from room temperature to 600°C in air at a heating rate of 40°C / min. <d-2>Polyphenylene sulfide resin: Manufactured by Toray Industries, Inc., 320°C, shear rate 10 sec -1 A polyphenylene sulfide resin was used, which had a melt viscosity of 80 Pa·s and a mass loss of 34% by mass when heated in air from room temperature to 600°C at a heating rate of 40°C / min. <d-3>Polyphenylene ether resin: Asahi Kasei Corporation's "Zylon" (registered trademark) S201A was used, which exhibits a mass loss of 42% by mass when heated in air from room temperature to 600°C at a heating rate of 40°C / min.

[0107] (E) Nitrogen-containing heterocyclic compounds having a triazine skeleton <e-1>Melamine cyanurate: Nissan Chemical Corporation's MC-4000 was used. (F) Core shell rubber <f-1>A core-shell rubber, "Metablen" (registered trademark) S-2001, manufactured by Mitsubishi Chemical Corporation, was used, in which the core layer is a dimethylsiloxane / butyl acrylate polymer and the outermost layer is a methyl methacrylate polymer. <f-2>Core-shell rubber with a butyl acrylate polymer core and a methyl methacrylate polymer outermost layer: "Paraloid" (registered trademark) EXL-2315, manufactured by Dow Chemical Japan Ltd. <f-3>The core-shell rubber used is "Metablen" (registered trademark) SX-005, manufactured by Mitsubishi Chemical Corporation, in which the core layer is a dimethylsiloxane / butyl acrylate polymer and the outermost layer is a methyl methacrylate polymer. <f-4>The core-shell rubber used is "Metablen" (registered trademark) SX-006, manufactured by Mitsubishi Chemical Corporation, in which the core is a dimethylsiloxane / butyl acrylate polymer and the outermost layer is a styrene / acrylonitrile polymer.

[0108] (G) Hindered amine compounds <g-1>Bis-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-butyl(3,5-di-t-butyl-4-hydroxybenzyl)malonate: Tinuvin 144, manufactured by BASF Ltd, with a melting point of 150°C was used.

[0109] (H) Fibrous reinforcing material <h-1>Glass fibers treated with a sizing agent containing epoxy compounds: Glass fibers ECS03T-187 manufactured by Nippon Electric Glass Co., Ltd., with a cross-sectional diameter of 13 μm and a fiber length of 3 mm were used.

[0110] (I) Other components <i-1>Polyethylene terephthalate resin: A polyethylene terephthalate resin manufactured by Toray Industries, Inc. was used, with a carboxyl group content of 40 eq / t and an intrinsic viscosity of 0.63 dl / g measured at 25°C using o-chlorophenol as a solvent. <i-2>Fluorine-based resin: Polytetrafluoroethylene, specifically "Teflon" (registered trademark) 6-J manufactured by Mitsui DuPont Fluorochemicals Co., Ltd. was used. <i-3>The phosphinate metal salt used was aluminum diethylphosphinate, specifically "Exolit" (registered trademark) OP-1240 manufactured by Clariant Japan Co., Ltd. <i-4>Phosphazene compound: "Rabitol" (registered trademark) FP-110, manufactured by Fushimi Pharmaceutical Co., Ltd., was used.

[0111] [Measurement methods for each characteristic] In the examples and comparative examples, their characteristics were evaluated using the measurement methods described below.

[0112] (1) Electron microscopy observation of sea-island structures (average diameter of island phase and composite island phase of component (D)) Using a NEX1000 injection molding machine manufactured by Nissei Plastic Industrial Co., Ltd., strip-shaped test specimens measuring 125 mm × 13 mm × 1.6 mm thick were molded under the following molding cycle conditions: cylinder temperature 260°C, mold temperature 80°C, injection time and holding time combined 10 seconds, and cooling time 10 seconds. The center of the cross-sectional direction of the strip-shaped test specimen was cut into 1-1.6 mm squares to obtain samples for electron microscopy. After staining the electron microscope samples with ruthenium tetroxide, platinum-palladium was deposited by sputtering, and then SEM images and elemental mapping images were obtained using a field emission scanning electron microscope (FE-SEM) and energy dispersion method. To identify the island phase of component (D) from the elemental mapping images and SEM images and determine its average diameter, the magnification was adjusted so that there were between 100 and 200 island phases of component (D) in the square electron microscope image. At this magnification, the largest 20 island phases of component (D) were selected from the observed image, and the major and minor axes were measured for each island phase. The average of these major and minor axes was taken as the diameter of each component (D) island phase, and the average of the measured diameters of all component (D) island phases was taken as the diameter of the island phase. The major and minor axes of the component (D) island phases were defined as the longest and shortest diameters, respectively. The values ​​were the average of the measurements taken from three test specimens.

[0113] When component (C) was incorporated, electron microscope observation was performed in the same manner as above. If the island phase of component (D) was contained within the island phase of component (C), it was determined that a composite island phase had been formed, and the average diameter of the composite island phase was calculated in the same manner.

[0114] (2) Flame retardancy (combustion rank) Using a NEX1000 injection molding machine manufactured by Nissei Plastic Industrial Co., Ltd., a combustion test specimen measuring 125 mm × 13 mm × 1.6 mm thick was obtained under the following molding cycle conditions: cylinder temperature 260°C, mold temperature 80°C, injection time and holding pressure time combined 10 seconds, and cooling time 10 seconds. The flame retardancy of the obtained combustion test specimen was evaluated according to the evaluation criteria specified in the UL94 vertical test. Flame retardancy is ranked in the order of V-0 > V-1 > V-2, decreasing in that order. Materials that were inferior in flame retardancy and did not fall into the above flame retardancy ranks were classified as out of specification (V-out). Materials ranked as V-1 or V-2, or classified as out of specification, were judged to have inferior flame retardancy. Furthermore, even among the materials classified as V-0, those in which no test specimens exceeded 10 seconds in maximum burning time after the first or second flame exposure when 20 more test specimens were evaluated showed no variation in flammability and were judged to have stable flame retardancy.

[0115] (3) Tracking resistance and its wet heat stability Using a NEX1000 injection molding machine manufactured by Nissei Plastic Industrial Co., Ltd., injection molding was performed under the same injection molding conditions as in item (1) above to obtain a rectangular plate measuring 80 mm × 80 mm × 3 mm thick. Using the obtained rectangular plate, the comparative tracking index was measured in accordance with the measurement method for comparative tracking index of 600 V or less specified in IEC60112:2003, using a 0.1% ammonium chloride aqueous solution as the electrolyte solution. For comparative tracking indexes exceeding 600 V, the evaluation was performed by reversing the platinum electrode as per the IEC60112:2003 standard. A higher comparative tracking index value was evaluated as indicating better tracking resistance, with values ​​above 500 V being particularly excellent, values ​​above 600 V being even better, and values ​​above 700 V being even better, while values ​​below 500 V were judged to indicate poor tracking resistance.

[0116] Furthermore, the obtained rectangular plates were placed in an EHS-411 advanced accelerated life test apparatus manufactured by ESPEC Corporation, set to a temperature and humidity of 121°C × 100%RH, and subjected to 100 hours of moist heat treatment. The comparative tracking index of the rectangular plates after moist heat treatment was evaluated in the same manner as above, and it was determined that a value of 500V or higher indicated superior tracking resistance.

[0117] (4) Bleed-out resistance (bleeding after dry heat or wet heat treatment) Using a NEX1000 injection molding machine manufactured by Nissei Plastic Industrial Co., Ltd., injection molding was performed under the same injection molding conditions as in item (1) above to obtain a test specimen measuring 125 mm × 13 mm × 1.6 mm thick. To evaluate the bleed-out resistance in a dry heat environment, the obtained test specimen was placed in an ESPEC Corporation PHV-222 constant temperature chamber set to 150°C and subjected to dry heat treatment for 100 hours. To evaluate the bleed-out resistance in a humid heat environment, the specimen was placed in an ESPEC Corporation EHS-411 advanced accelerated life tester set to 121°C × 100% RH and humidity and subjected to humid heat treatment for 100 hours. The appearance of the molded product after dry heat treatment and humid heat treatment was visually observed, and bleed-out was determined according to the following criteria. A: No liquid or powdery bleed-out is observed in the molded product. B: Liquid or powdery bleed-out is observed in some or all parts of the molded product.

[0118] Materials that did not exhibit bleed-out after 100 hours of dry heat treatment were evaluated as having excellent bleed-out resistance, and materials that did not exhibit bleed-out after 100 hours of wet heat treatment were evaluated as having even better bleed-out resistance. Materials that exhibited bleed-out under either condition were judged to have poor bleed-out resistance.

[0119] (5) Weld strength (maximum tensile strength of the welded area) Using a NEX1000 injection molding machine manufactured by Nissei Plastic Industrial Co., Ltd., injection molding was performed under the same injection molding conditions as in item (1) above to obtain a test specimen for evaluating the weld properties of an ASTM No. 1 dumbbell (1 / 8 inch thickness) with a weld formed in the center. The tensile maximum point strength (weld strength) of the obtained ASTM No. 1 dumbbell with a weld was measured according to ASTM D638 (2005), and the average value of three measured values ​​was calculated.

[0120] Materials with higher tensile maximum strength were evaluated as having superior weld strength, and those with a tensile maximum strength of less than 20 MPa were judged to have inferior weld strength.

[0121] [Examples 1-35], [Comparative Examples 1-11] Using a twin-screw extruder with a screw diameter of 30 mm and an L / D ratio of 35, and equipped with a co-rotating vent (manufactured by Japan Steel Works, TEX-30α), (A) polybutylene terephthalate resin, (B) phosphate ester compound, (C), (F) styrene resin and / or core-shell rubber, and (D) flame-retardant resin, and optionally (E) nitrogen-containing heterocyclic compound having a triazine skeleton, (G) hindered amine compound, (H) fibrous reinforcing material, and (I) other components were mixed in the compositions shown in Tables 1 to 4 and added from the breech section of the twin-screw extruder. The fibrous reinforcing material (H) was added by installing a side feeder between the breech section and the vent section. The cylinder temperature was set to the values ​​shown in Tables 1 to 4, and the extrusion conditions were 200 rpm screw rotation and 30 kg / h processing rate. The mixture was melted and mixed, extruded in strand form from the discharge hole, passed through a cooling bath, and pelletized by a strand cutter. The resin temperature was measured by bringing a thermocouple into contact with the molten resin composition in the hole during the dispensing process.

[0122] The obtained pellets were dried in a hot air dryer at 130°C for 6 hours, and then evaluated using the method described above. The results are shown in Tables 1 to 4.

[0123] The ratio of parts by mass of component (C) to parts by mass of component (D) ([parts by mass of component (C) per 100 parts by mass of component (A)] / [parts by mass of component (D) per 100 parts by mass of component (A)]) is expressed as "(C) / (D)".

[0124] The ratio of parts by mass of component (B) to parts by mass of component (G) ([parts by mass of component (B) per 100 parts by mass of component (A)] / [parts by mass of component (G) per 100 parts by mass of component (A)]) is expressed as "(B) / (G)".

[0125] [Table 1]

[0126] [Table 2]

[0127] [Table 3]

[0128] [Table 4]

[0129] By comparing the examples and comparative examples, it was found that by blending components (B) and (D) in specific ranges with 100 parts by mass of component (A), and setting the average diameter of component (D) within a specific range, a material with excellent flame retardancy, tracking resistance, bleed-out resistance, and weld strength was obtained.

[0130] By comparing Examples 12, 14, 15, 16, and 17 with Comparative Examples 8, 10, and 11, it was found that incorporating component (C) and setting the (C) / (D) ratio to 0.5-4.0 resulted in a material with a better balance of flame retardancy, tracking resistance, bleed-out resistance, and weld strength.

[0131] By comparing Example 2 with Example 1 and Comparative Example 2, it was found that using polyphenylene sulfide resin as (D) flame retardant resin yielded a material with a better balance of flame retardancy, tracking resistance, bleed-out resistance, and weld strength.

[0132] By comparing Examples 13, 23, 24, and 25 with Example 12, it was found that by further incorporating a specific amount of (F) core-shell rubber, a material with a better balance of flame retardancy, tracking resistance, bleed-out resistance, and weld strength was obtained.

[0133] A comparison of Example 2 and Example 4 showed that by using less than 5 parts by mass of polyethylene terephthalate resin per 100 parts by mass of polybutylene terephthalate resin (A), a material with superior tracking resistance, bleed-out resistance, and maximum tensile strength was obtained.

[0134] By comparing Examples 2 and 3 with Comparative Example 1, it was found that by blending (A) polyphenylene ether resin in an amount of less than 5 parts by mass per 100 parts by mass of polybutylene terephthalate resin, a material with excellent tracking resistance, bleed-out resistance, and maximum tensile strength was obtained.

[0135] By comparing Example 2 and Example 5, it was found that by using less than 0.05 parts by mass of fluororesin per 100 parts by mass of (A) polybutylene terephthalate resin, a PFAS-free material with superior weld strength was obtained.

[0136] A comparison of Example 2 with Examples 6 and 7 revealed that by using less than 5 parts by mass of phosphinate metal salt and phosphazene compound per 100 parts by mass of (A) polybutylene terephthalate resin, a material with superior tracking resistance and bleed-out resistance was obtained.

[0137] A comparison of Examples 2 and 8 with Comparative Examples 3 and 4 revealed that when the resin temperature during melt mixing is between 285°C and 335°C, the average diameter of component (D) is refined, resulting in a material with excellent flame retardancy, tracking resistance, bleed-out resistance, and weld strength.

Claims

1. A polybutylene terephthalate resin composition comprising: (A) 100 parts by mass of polybutylene terephthalate resin, (B) 10 to 120 parts by mass of a phosphate ester compound, (D) 1 to 20 parts by mass of a flame retardant resin, and (E) 10 to 150 parts by mass of a nitrogen-based flame retardant which is a nitrogen-containing heterocyclic compound having a triazine skeleton, wherein the island phase of the flame retardant resin (D) is dispersed in the sea phase of the polybutylene terephthalate resin (A) with an average diameter of 0.05 to 5.0 μm, and the mass loss of the flame retardant resin (D) when heated in air from room temperature to 600°C at a heating rate of 40°C / min is 70% by mass or less.

2. The polybutylene terephthalate resin composition according to claim 1, comprising 100 parts by mass of (A) polybutylene terephthalate resin, further comprising 1 to 40 parts by mass of (C) styrene resin, wherein the ratio of the amount of (C) styrene resin to the amount of (D) flame retardant resin [(C) styrene resin / (D) flame retardant resin] is 0.5 to 4.

0.

3. The polybutylene terephthalate resin composition according to claim 2, wherein a composite island phase of (C) a styrene-based resin and (D) a flame-retardant resin is dispersed in the sea phase of (A) a polybutylene terephthalate resin with an average diameter of 1 to 20 μm.

4. The polybutylene terephthalate resin composition according to claim 1 or 2, wherein the flame-retardant resin (D) is a polyphenylene sulfide resin.

5. The polybutylene terephthalate resin composition according to claim 1 or 2, further comprising 1 to 40 parts by mass of (F) core-shell rubber per 100 parts by mass of (A) polybutylene terephthalate resin.

6. The polybutylene terephthalate resin composition according to claim 1 or 2, further comprising 0.3 to 3.0 parts by mass of (G) a hindered amine compound with respect to 100 parts by mass of (A) polybutylene terephthalate resin.

7. The polybutylene terephthalate resin composition according to claim 1 or 2, wherein the content of each of the polyethylene terephthalate resin, polyphenylene ether resin, and polyetherimide resin is less than 5 parts by mass per 100 parts by mass of the polybutylene terephthalate resin (A).

8. (A) The polybutylene terephthalate resin composition according to claim 1 or 2, wherein the content of fluororesin per 100 parts by mass of polybutylene terephthalate resin is less than 0.5 parts by mass.

9. (A) The polybutylene terephthalate resin composition according to claim 1 or 2, wherein the content of either the phosphazene compound or the organophosphinate metal salt is less than 5 parts by mass per 100 parts by mass of the polybutylene terephthalate resin.

10. A molded article obtained by melt-molding the polybutylene terephthalate resin composition according to claim 1 or 2.

11. A high-voltage insulating component comprising the polybutylene terephthalate resin composition according to claim 1 or 2.

12. The high-voltage insulating component according to claim 11, which is a high-voltage connector, a power module case, or a busbar.

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