Polyamide resin composition and metal-resin composite

Abstract

To provide a polyamide resin composition for insert molding, wherein the polyamide resin composition can enhance flame retardancy while sufficiently enhancing tracking resistance, and also to provide a metal-resin composite using the same.SOLUTION: A polyamide resin composition for insert molding contains a semi-aromatic polyamide resin (A1) having a melting point of 280°C or higher, a halogen-based flame retardant (B), a heat-absorbing filler (C), a fibrous reinforcing material (D), and scaly or platy inorganic particles (E), wherein the content of the halogen-based flame retardant (B) is 21.5 mass% or more and 35.0 mass% or less with respect to the total mass of thermoplastic resin contained in the polyamide resin composition.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a polyamide resin composition and a metal-resin composite. [Background technology]

[0002] Polyamide resin compositions have been known as molding materials. Polyamide resin compositions are widely used as materials for various parts, such as automobile parts and electric / electronic parts, and are known to produce molded articles with excellent mechanical strength.

[0003] For example, Patent Document 1 discloses a mobile phone housing made of a polyamide resin composition containing a specific amount of glass fiber and glass flakes. Patent Document 1 states that the polyamide resin composition enables the housing to achieve good rigidity and impact resistance and low warpage after molding.

[0004] Incidentally, polyamide resin compositions are sometimes used to form metal-resin composites in which a resin member obtained by molding the polyamide resin composition is combined with a metal member. It is known that such metal-resin composites can be obtained, for example, by insert molding. When such metal-resin composites are used in automotive parts (e.g., bus bars) and electrical / electronic parts, tracking failure may occur. Therefore, when polyamide resin compositions are used for these applications, it is necessary to improve the tracking resistance of the resin members.

[0005] For example, Patent Document 2 discloses a flame-retardant resin composition comprising a polyamide resin, a halogen-based flame retardant (such as brominated polystyrene), an organic phosphinic acid or its salt, and a flame-retardant assistant. According to Patent Document 2, the flame-retardant resin composition is said to have improved flame retardancy and tracking resistance. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2010-510374 [Patent Document 2] International Publication No. 2006 / 090751 Summary of the Invention [Problem to be solved by the invention]

[0007] According to the investigations of the present inventors, the polyamide resin compositions described in Patent Documents 1 and 2 could not sufficiently improve the tracking resistance of the resin member.

[0008] Furthermore, for example, in applications such as automobile parts and electric / electronic parts, polyamide resin compositions having high flame retardancy may be required.

[0009] An object of the present invention is to provide a polyamide resin composition for insert molding that can sufficiently improve tracking resistance while also improving flame retardancy, and a metal-resin joined body using the same. [Means for solving the problem]

[0010] In order to solve the above problems, one aspect of the present invention relates to the following polyamide resin compositions [1] to [5]. [1] A polyamide resin composition for insert molding, a polyamide resin (A1) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC); a halogen-based flame retardant (B); an endothermic filler (C); A fibrous reinforcing material (D); scaly or plate-like inorganic particles (E); Including, the content of the halogen-based flame retardant (B) is 21.5 mass% or more and 35.0 mass% or less based on the total mass of the thermoplastic resin contained in the polyamide resin composition; Polyamide resin composition. [2] Further containing a polyamide resin (A2) having a heat of fusion (ΔH) measured by a differential scanning calorimeter (DSC) of 0 J / g or more and 5 J / g or less, [1] The polyamide resin composition according to [1]. [3] The content of the polyamide resin (A2) is 3% by mass or more and 25% by mass or less based on the total mass of the polyamide resin (A1) and the polyamide resin (A2). [1] or [2]. The polyamide resin composition. [4] When the inorganic particles (E) are mica particles, the content of the halogen-based flame retardant (B) is 20% by mass or more and 25% by mass or less based on the total mass of the thermoplastic resin, When the inorganic particles (E) are glass flakes, the content of the halogen-based flame retardant (B) is 22 mass% or more and 35 mass% or less with respect to the total mass of the thermoplastic resin. The polyamide resin composition according to any one of [1] to [3]. [5] Further comprising a fibrous reinforcing material (D), The polyamide resin composition according to any one of [1] to [4].

[0011] In order to solve the above problems, another aspect of the present invention relates to the metal-resin bonded body described below in [6]. [6] A metal member; and a resin member comprising the polyamide resin composition according to any one of [1] to [5], which is composited on the surface of the metal member. Metal resin composite. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a polyamide resin composition for insert molding that can sufficiently improve tracking resistance while also improving flame retardancy, and a metal resin composite using the same. [Brief explanation of the drawings]

[0013] [Figure 1]FIG. 1 is a schematic diagram showing an exemplary embodiment of a metal-resin composite as a busbar unit. [Figure 2] FIG. 2 is a configuration diagram showing an exemplary configuration of a moving body (vehicle) having a busbar unit. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments.

[0015] 1. Polyamide resin composition The polyamide resin composition according to the present embodiment is a polyamide resin composition for insert molding, and comprises a polyamide resin (A1) having a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC), a halogenated flame retardant (B), an endothermic filler (C), a fibrous reinforcing material (D), and scale-like or plate-like inorganic particles (E). The content of the halogenated flame retardant (B) is 21.5% by mass or more and 35.0% by mass or less, based on the total mass of the thermoplastic resin contained in the polyamide resin composition.

[0016] When a resin member containing a polyamide resin composition is used as an insulating member for insulating a conductive member, a voltage is applied to the resin member containing the polyamide resin composition. It is known that if a voltage is applied to the surface of a resin member containing a polyamide resin composition with minute amounts of dirt and moisture attached thereto, tracking breakdown can occur. Specifically, the dirt and moisture act as electrical pathways, causing leakage current to flow between the electrodes, resulting in Joule heat. This Joule heat evaporates the moisture, forming a dry area (dry zone). Because the dry zone has high insulation resistance, applying a high voltage across the dry zone generates scintillation discharge. This supplies thermal energy to the surface of the resin member, causing carbonization and precipitation of char on the surface of the resin member. Repeated discharges then cause the char precipitated on the surface of the molded article to grow into carbonized areas, which then bridge the electrodes, resulting in tracking breakdown.

[0017] According to the findings of the present inventors, while the halogenated flame retardant (B) described in Patent Document 2 can impart flame retardancy to a resin member containing a polyamide resin composition, it is prone to causing the tracking fracture. In particular, when a styrene-containing halogenated flame retardant such as brominated polystyrene or polybrominated styrene is used as the halogenated flame retardant (B), the aromatic ring concentration of the halogenated flame retardant (B) itself is high, which increases the aromatic ring concentration of the entire polyamide resin composition, making the tracking fracture more likely to occur. Therefore, it is desirable to reduce the content of the halogenated flame retardant (B). However, simply reducing the content of these compounds within a range that maintains the flame retardancy of the polyamide resin composition did not improve the tracking resistance of the polyamide resin composition.

[0018] Therefore, the present inventors attempted to improve tracking resistance by using an endothermic filler (C). It is believed that the endothermic filler (C) can absorb most of the thermal energy supplied to the surface of the molded body when the scintillation discharge occurs. The thermal energy absorbed by the endothermic filler (C) is consumed in the decomposition reaction of the endothermic filler, so the amount of thermal energy supplied to the surface of the molded body can be reduced, and carbonization deterioration of the surface of the molded body can be suppressed. The present inventors believed that this would make carbonization deterioration and tracking failure of the surface of the resin part less likely to occur, thereby improving tracking resistance.

[0019] However, even in polyamide resin compositions in which the content of the halogen-based flame retardant (B) is reduced and the heat-absorbing filler (C) is added, the tracking resistance is not sufficiently improved.

[0020] The inventors investigated the reasons and found that when the surface of the resin member is low in smoothness, the tracking resistance is not sufficiently improved. When the surface of the resin member is low in smoothness, relatively large irregularities exist on the surface of the resin member. When such irregularities exist, the Joule heat caused by the leakage current described above makes it easier for the dry bands described above to form on the convex portions. In other words, the dry bands tend to be concentrated and formed at specific positions on the surface of the molded body. As a result, scintillation discharges also tend to be concentrated and generated at specific positions on the surface of the molded body (on the convex portions described above), which makes it easier for carbide deposition on the surface of the molded body to be promoted at specific positions. The precipitated carbides then make it easier for tracking failure to occur.

[0021] In response to this, the present inventors have conducted extensive research and found that the use of scaly or plate-like inorganic particles (E) can improve the tracking resistance of the resin workpiece. It is believed that the use of scaly or plate-like inorganic particles (E) can improve the surface smoothness of the resin workpiece obtained by molding the polyamide resin composition.

[0022] Furthermore, by improving the smoothness of the resin member surface, the resin member surface does not have the above-mentioned relatively large convex portions, or even if they do, the probability of their existence is low. Therefore, the dry zones are not concentrated in specific locations on the surface of the molded body, but are formed randomly over a wide area of ​​the surface of the molded body. This causes scintillation discharges to occur randomly over a wide area of ​​the surface of the molded body, preventing them from concentrating in specific locations, and dispersing the thermal energy supplied to the surface of the molded body by the scintillation discharge. As a result, it is thought that carbides are prevented from concentrating and precipitating in specific locations on the surface of the molded body, and the generation of carbides that serve as starting points for carbonization growth is suppressed.

[0023] Based on these findings, the present inventors have conducted extensive research and found that the flame retardancy of the resin part can be improved while also sufficiently improving tracking resistance by setting the content of the brominated polystyrene or the polybrominated styrene (B) to 21.5 mass % or more and 35.0 mass % or less, relative to the total mass of the thermoplastic resin contained in the polyamide resin composition, and the content of the phosphinate compound (C) to 0.5 mass % or more, relative to the total mass of the polyamide resin composition.

[0024] 1. Polyamide resin (A1) The polyamide resin (A1) is a polyamide resin having a melting point of 280° C. or higher as measured by a differential scanning calorimeter (DSC). The polyamide resin (A1) forms crystals in a molded article, and can increase the mechanical strength (such as tensile strength) of the molded article.

[0025] The polyamide resin (A1) is, for example, a polyamide resin containing a component unit (A1a) derived from a dicarboxylic acid and a component unit (A1b) derived from a diamine. Hereinafter, the polyamide resin containing the component unit (A1a) derived from a dicarboxylic acid and the component unit (A1b) derived from a diamine will be described.

[0026] (Constituent unit (A1a) derived from dicarboxylic acid) The dicarboxylic acid-derived constituent units (A1a) preferably include constituent units derived from an aromatic dicarboxylic acid, and more preferably include constituent units derived from terephthalic acid.

[0027] The content of the component units derived from terephthalic acid is preferably 20 mol% to 95 mol% of the total number of moles of the component units (A1a) derived from dicarboxylic acids, more preferably 30 mol% to 90 mol%, even more preferably 40 mol% to 85 mol%, and even more preferably 40 mol% to 65 mol%. When the content is 20 mol% or more, the melting point of the polyamide resin (A1) increases, and the heat resistance of the resin member increases.

[0028] The dicarboxylic acid-derived unit (A1a) may contain other dicarboxylic acid-derived units. Examples of other dicarboxylic acids include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids other than terephthalic acid. Of these, aliphatic dicarboxylic acids are preferred.

[0029] Examples of the aliphatic dicarboxylic acid include aliphatic dicarboxylic acids having 4 to 20 carbon atoms. The number of carbon atoms is preferably 6 to 12. Examples of such aliphatic dicarboxylic acids include adipic acid, azelaic acid, and sebacic acid. Among these, adipic acid and sebacic acid are preferred, and adipic acid is more preferred.

[0030] The content of the component units derived from the above aliphatic dicarboxylic acid is preferably 0 mol % or more and 60 mol % or less, and more preferably 0 mol % or more and 45 mol % or less, relative to the total number of moles of the component units (A1a) derived from the dicarboxylic acid.

[0031] Examples of the alicyclic dicarboxylic acid include cyclohexanedicarboxylic acid and its esters.

[0032] Examples of aromatic dicarboxylic acids other than terephthalic acid include isophthalic acid, 2-methylterephthalic acid, and naphthalenedicarboxylic acid.

[0033] The content of component units derived from alicyclic dicarboxylic acids and aromatic dicarboxylic acids other than terephthalic acid is preferably from 20 mol % to 80 mol % and more preferably from 25 mol % to 75 mol % relative to the total number of moles of component units (A1a) derived from dicarboxylic acids.

[0034] (Diamine-derived component unit (A1b)) The diamine-derived component unit (A1b) includes, for example, a component unit derived from an aliphatic diamine having from 4 to 15 carbon atoms, a component unit derived from an alicyclic diamine having from 4 to 20 carbon atoms, and a component unit derived from an aromatic diamine.

[0035] The number of carbon atoms in the aliphatic diamine is preferably 4 or more and 12 or less, and more preferably 6 or more and 12 or less. Examples of the aliphatic diamine include linear alkylenediamines and branched alkylenediamines.

[0036] Examples of the linear alkylenediamine include 1,4-diaminobutane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane. Among these, 1,6-diaminohexane, 1,9-nonanediamine, and 1,10-diaminodecane are preferred, and 1,6-diaminohexane is more preferred. The linear alkylenediamine may be contained alone or in combination of two or more.

[0037] Examples of the branched alkylenediamine include 2,2-dimethyldiaminopropane, 1,1-dimethyl-1,4-diaminobutane, 1-ethyl-1,4-diaminobutane, 1,2-dimethyl-1,4-diaminobutane, 1,3-dimethyl-1,4-diaminobutane, 1,4-dimethyl-1,4-diaminobutane, 2,3-dimethyl-1,4-diaminobutane, 2-methyl-1,5-diaminopentane, 2,5-dimethyl-1,6-diaminohexane, 2,4 -Dimethyl-1,6-diaminohexane, 3,3-dimethyl-1,6-diaminohexane, 2,2-dimethyl-1,6-diaminohexane, 2,2,4-trimethyl-1,6-diaminohexane, 2,4,4-trimethyl-1,6-diaminohexane, 2,4-diethyl-1,6-diaminohexane, 2,3-dimethyl-1,7-diaminoheptane, 2,4-dimethyl-1,7-diaminoheptane, 2,5-dimethyl-1,7-diaminoheptane, 2,2- Dimethyl-1,7-diaminoheptane, 2-methyl-4-ethyl-1,7-diaminoheptane, 2-ethyl-4-methyl-1,7-diaminoheptane, 2,2,5,5-tetramethyl-1,7-diaminoheptane, 3-isopropyl-1,7-diaminoheptane, 3-isooctyl-1,7-diaminoheptane, 2-methyl-1,8-diaminooctane, 1,3-dimethyl-1,8-diaminooctane, 1,4-dimethyl-1,8-diaminooctane, 2, These include 4-dimethyl-1,8-diaminooctane, 3,4-dimethyl-1,8-diaminooctane, 4,5-dimethyl-1,8-diaminooctane, 2,2-dimethyl-1,8-diaminooctane, 3,3-dimethyl-1,8-diaminooctane, 4,4-dimethyl-1,8-diaminooctane, 3,3,5-trimethyl-1,8-diaminooctane, 2,4-diethyl-1,8-diaminooctane, and 5-methyl-1,9-diaminononane. Among these, 2-methyl-1,5-diaminopentane is preferred.

[0038] The content of the component units derived from the aliphatic diamine is preferably 30 mol % or more and 100 mol % or less, and more preferably 70 mol % or more and 100 mol % or less, based on the total number of moles of the component units (A1b) derived from the diamine.

[0039] Examples of the alicyclic diamine having 4 to 20 carbon atoms include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 2,5-bisaminomethylnorbornane, and 2,6-bisaminomethylnorbornane. Examples of the aromatic diamine include metaxylylenediamine.

[0040] The constituent units of the polyamide resin (A1) and their ratios can be calculated from the ratios charged when the polyamide resin (A1) is prepared, or can be measured by NMR.

[0041] 1 In the case of H-NMR measurement, for example, a nuclear magnetic resonance apparatus (ECX400 model manufactured by JEOL Ltd.) is used, the solvent is deuterated orthodichlorobenzene, the sample concentration is 20 mg / 0.6 mL, the measurement temperature is 120 °C, and the observation nucleus is 1 The conditions are H (400 MHz), sequence is single pulse, pulse width is 5.12 μsec (45° pulse), repetition time is 7.0 sec, and the number of accumulations is 500 or more. The reference chemical shift is set to 0 ppm for hydrogen in tetramethylsilane, but similar results can also be obtained by setting the peak derived from residual hydrogen in deuterated orthodichlorobenzene at 7.10 ppm as the reference value for the chemical shift. 1 Peaks such as H can be assigned by conventional methods.

[0042] 13 In the case of C-NMR measurement, for example, a nuclear magnetic resonance apparatus (ECP500 model manufactured by JEOL Ltd.) is used as the measurement apparatus, a mixed solvent of ortho-dichlorobenzene / heavy benzene (80 / 20% by volume) is used as the solvent, the measurement temperature is 120°C, and the observation nucleus is 13 The conditions were: C (125 MHz), single pulse proton decoupling, 45° pulse, repetition time 5.5 seconds, accumulation number 10,000 or more, and chemical shift reference value 27.50 ppm. Assignment of various signals was performed based on the standard method, and quantification could be performed based on the accumulated value of signal intensity.

[0043] The dicarboxylic acid-derived component units of the polyamide resin (A1) may include component units derived from a biomass-derived dicarboxylic acid, and the diamine-derived component units may include component units derived from a biomass-derived diamine. The polyamide resin (A1) may also be a biomass-derived polyamide resin (A1) obtained by polymerizing raw materials including a biomass-derived raw material.

[0044] Specific examples of the polyamide resin (A1) include polyamide 6T6I, polyamide 6T66, polyamide 6TDT, polyamide 6T6I66, polyamide 9T, polyamide 10T, and the like.

[0045] The polyamide resin (A1) can be produced by the same method as that for known polyamide resins, for example, by polycondensing a dicarboxylic acid and a diamine in a homogeneous solution. Specifically, the polyamide resin (A1) can be produced by heating a dicarboxylic acid and a diamine in the presence of a catalyst to obtain a low-order condensate, as described in WO 03 / 085029, and then applying shear stress to a melt of the low-order condensate to polycondense it.

[0046] The content of the polyamide resin (A1) is preferably 15% by mass or more and 70% by mass or less, more preferably 20% by mass or more and 60% by mass or less, and more preferably 22% by mass or more and 50% by mass or less, based on the total mass of the polyamide resin composition. When the content is 15% by mass or more, the mechanical strength of the polyamide resin composition can be increased. When the content is 70% by mass or less, the other components described below can be sufficiently contained in the polyamide resin composition.

[0047] (Physical Properties) From the viewpoint of further increasing the mechanical strength of the molded article, the melting point of the polyamide resin (A1) is 280° C. or higher, preferably 290° C. or higher, and more preferably 300° C. or higher. From the viewpoint of suppressing decomposition of the amide bond of the polyamide resin (A1), the melting point of the polyamide resin (A1) is preferably 340° C. or lower, and more preferably 330° C. or lower.

[0048] The melting point of the polyamide resin (A1) can be adjusted to the above range by adjusting the composition of the polyamide resin (A1). For example, the melting point can be increased by increasing the content of component units derived from terephthalic acid, which will be described later.

[0049] The polyamide resin (A1) preferably has a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of more than 70°C and not more than 145°C, more preferably from 75°C to 145°C, and even more preferably from 80°C to 145°C. If the glass transition temperature (Tg) is more than 70°C, the temperature at which molecular mobility becomes active in a high-temperature environment increases, thereby suppressing molecular mobility and further improving the heat resistance of the polyamide resin composition and molded article. If the glass transition temperature (Tg) is not more than 145°C, the fluidity of the resin composition can be easily maintained without excessively increasing the mold temperature during molding, thereby improving molding processability.

[0050] The heat of fusion (ΔH) of the polyamide resin (A1) measured by differential scanning calorimetry (DSC) is preferably greater than 5 J / g. The heat of fusion is an index of the crystallinity of a resin, and a larger heat of fusion indicates higher crystallinity. When the heat of fusion (ΔH) of the polyamide resin (A) exceeds 5 J / g, the crystallinity is increased, and the mechanical strength (tensile strength, flexural strength, etc.) of the resulting molded article can be increased.

[0051] The melting point and heat of fusion (ΔH) of the polyamide resin (A1) can be measured using a differential scanning calorimeter (DSC220C model, manufactured by Seiko Instruments Inc.).

[0052] Specifically, approximately 5 mg of polyamide resin (A1) is sealed in a measuring aluminum pan and heated from room temperature to 350°C at 10°C / min. To completely melt the resin, it is held at 350°C for 3 minutes and then cooled to 30°C at 10°C / min. After leaving it at 30°C for 5 minutes, it is heated a second time to 350°C at 10°C / min. The temperature (°C) of the endothermic peak during this second heating is taken as the melting point (Tm) of polyamide resin (A), and the inflection point corresponding to the glass transition is taken as the glass transition temperature (Tg). The heat of fusion (ΔH) is determined from the area of ​​the endothermic peak during melting during the first heating process in accordance with JIS K7122.

[0053] The intrinsic viscosity [η] of the polyamide resin (A1), measured in 96.5% sulfuric acid at 25°C, is preferably 0.60 dL / g to 1.50 dL / g, more preferably 0.70 dL / g to 1.20 dL / g, and particularly preferably 0.75 dL / g to 1.10 dL / g. When the polyamide resin (A1) has an intrinsic viscosity [η] of 0.60 dL / g or higher, the mechanical strength (e.g., bending strength) of the molded article is easily increased. When the intrinsic viscosity [η] is 1.50 dL / g or lower, the fluidity of the resin composition during molding is less likely to be impaired. The intrinsic viscosity [η] can be adjusted by adjusting the molar ratio of the dicarboxylic acid-derived component unit (A1a) and the diamine-derived component unit (A1b). Specifically, the closer the molar ratio of the carboxylic acid-derived component unit (A1a) and the diamine-derived component unit (A1b) is to 1:1, the higher the intrinsic viscosity can be. It can also be adjusted by the amount of end-capping of the polyamide resin (A1).

[0054] The intrinsic viscosity [η] of the polyamide resin (A1) can be measured as follows. 0.5 g of the polyamide resin (A1) is dissolved in 50 ml of a 96.5% sulfuric acid solution to prepare a sample solution. The flow time of the obtained solution at 25°C ± 0.05°C is measured using an Ubbelohde viscometer, and the intrinsic viscosity [η] is calculated based on the following formula: [η]=ηSP / (C*(1+0.205ηSP)) [η]: Intrinsic viscosity (dl / g) ηSP: Specific viscosity C: Sample concentration (g / dl) t: Number of seconds for sample solution to flow down (seconds) t0: Number of seconds the blank sulfuric acid flows (seconds) ηSP=(t-t0) / t0

[0055] The amount of terminal amino groups in the polyamide resin (A1) is preferably 10 mmol / kg or more and 200 mmol / kg or less, more preferably 15 mmol / kg or more and 150 mmol / kg or less, and even more preferably 20 mmol / kg or more and 130 mmol / kg or less. When the amount of terminal amino groups in the polyamide resin (A1) is 10 mmol / kg or more, the polyamide resin (A1) is likely to chemically interact with the surface treatment agent or sizing agent of the fibrous reinforcing material (D) and the scaly or plate-like inorganic particles (E), thereby making it easier to disperse the fibrous reinforcing material (D) and the scaly or plate-like inorganic particles (E). When the amount of terminal amino groups in the polyamide resin (A1) is 200 mmol / kg or less, the chemical interaction between the polyamide resin (A1) and the fibrous reinforcing material (D) and the scaly or plate-like inorganic particles (E) is unlikely to be excessive, thereby ensuring sufficient fluidity of the polyamide resin composition.

[0056] The amount of terminal carboxylic acid groups in the polyamide resin (A1) is preferably 60 mmol / kg or more and 220 mmol / kg or less, more preferably 80 mmol / kg or more and 200 mmol / kg or less, and even more preferably 100 mmol / kg or more and 180 mmol / kg or less.

[0057] 1-2. Polyamide resin (A2) In this embodiment, from the viewpoint of enhancing the heat shock resistance of the resin member, it is preferable that the polyamide resin composition further contains a polyamide resin (A2) having a heat of fusion (ΔH) measured by a differential scanning calorimeter (DSC) of 0 J / g or more and 5 J / g or less.

[0058] In a metal-resin composite, when the ambient temperature changes from high to low, the resin member containing the polyamide resin composition shrinks. When the resin member shrinks, the resin member shrinks more than the metal member because of the large difference in the linear expansion coefficient between the resin member and the metal member. At this time, stress related to the shrinkage of the resin member is thought to be generated at the interface between the resin member and the metal member. It is thought that the generation of this stress causes cracks in the resin member, resulting in poor heat shock resistance.

[0059] The polyamide resin (A2) has lower crystallinity than the polyamide resin (A1), and therefore can reduce the degree of crystallinity in the polyamide resin composition. This reduces the shrinkage rate of a resin workpiece containing the polyamide resin composition, thereby reducing the stress generated between the resin workpiece and a metal workpiece. As a result, it is believed that cracking of the resin workpiece can be suppressed when the environmental temperature is lowered from a higher temperature, and the heat shock resistance of the resin workpiece can be improved.

[0060] The polyamide resin (A2) preferably has a melting point (Tm) that is not substantially measurable by differential scanning calorimetry (DSC). The phrase "having a melting point (Tm) that is not substantially measurable" means that a transition point corresponding to the melting point is not substantially observed in the above-mentioned measurement method.

[0061] The heat of fusion (ΔH) of the polyamide resin (A2) is 0 J / g or more and 5 J / g or less, and preferably 0 J / g. The polyamide resin (A2) is preferably amorphous. The heat of fusion (ΔH) of the polyamide resin (A2) can be measured by the same method as described for the polyamide (A1).

[0062] The polyamide resin (A2) is not particularly limited as long as it is a polyamide resin having a heat of fusion (ΔH) of 0 J / g or more and 5 J / g or less, but can be, for example, a polyamide containing a component unit (A2a) derived from a dicarboxylic acid and a component unit (A2b) derived from a diamine. Hereinafter, a case where the polyamide resin (A2) contains a component unit (A2a) derived from a dicarboxylic acid and a component unit (A2b) derived from a diamine will be described.

[0063] (Constituent unit (A2a) derived from dicarboxylic acid) The dicarboxylic acid-derived unit (A2a) preferably contains an isophthalic acid-derived unit, which can reduce the crystallinity of the polyamide resin (A2).

[0064] The content of the component units derived from isophthalic acid is preferably 40 mol% or more and 100 mol% or less, and more preferably 50 mol% or more and 100 mol% or less, relative to the total number of moles (A2a) of components derived from dicarboxylic acids in the polyamide resin (A2). When the content of the isophthalic acid component units is 40 mol% or more, the crystallinity of the polyamide resin (A2) can be further reduced.

[0065] The dicarboxylic acid-derived component units (A2a) may further contain component units derived from other dicarboxylic acids other than the isophthalic acid-derived component units, as long as the effects of the present invention are not impaired. Examples of other dicarboxylic acids include aromatic dicarboxylic acids other than isophthalic acid, such as terephthalic acid, 2-methylterephthalic acid, and naphthalenedicarboxylic acid, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. The aliphatic dicarboxylic acids and alicyclic dicarboxylic acids may be the same as the above-mentioned aliphatic dicarboxylic acids and alicyclic dicarboxylic acids, respectively. Among these, aromatic dicarboxylic acids other than isophthalic acid are preferred, and terephthalic acid is more preferred.

[0066] When the dicarboxylic acid-derived component units (A2a) further contain component units derived from terephthalic acid, the molar ratio of the isophthalic acid-derived component units to the terephthalic acid-derived component units (isophthalic acid-derived component units / terephthalic acid-derived component units) is preferably 55 / 45 to 95 / 5, more preferably 60 / 40 to 90 / 10, and even more preferably 60 / 40 to 80 / 20. When the molar ratio is within the above range, the crystallinity of the polyamide resin (A2) can be further reduced, and the occurrence of cracks at low temperatures in a resin workpiece containing the polyamide resin composition can be further suppressed, thereby further improving heat shock resistance.

[0067] (Diamine-derived component unit (A2b)) The diamine-derived component units (A2b) preferably include component units derived from an aliphatic diamine having from 4 to 15 carbon atoms.

[0068] The polyamide resin (A2) is preferably a polyamide in which, when the dicarboxylic acid-derived component units (A2a) include isophthalic acid-derived component units, the diamine-derived component units (A2b) include aliphatic diamine-derived component units having from 4 to 15 carbon atoms.

[0069] Examples of the aliphatic diamine having from 4 to 15 carbon atoms include those mentioned for the polyamide resin (A1). Of these, the aliphatic diamine is preferably 1,6-diaminohexane.

[0070] The content of the component units derived from the aliphatic diamine is preferably 50 mol % or more and 100 mol % or less, and more preferably 60 mol % or more and 100 mol % or less, based on the total number of moles of the component units (A2b) derived from the diamine.

[0071] The diamine-derived unit (A2b) may further contain other diamine-derived unit(s) in addition to the aliphatic diamine-derived unit(s), as long as the effects of the present invention are not impaired. Examples of the other diamines include alicyclic diamines and aromatic diamines. Examples of the alicyclic diamines and aromatic diamines include those described for the polyamide resin (A1). The content of the other diamine-derived unit(s) can be, for example, 10 mol % or less based on the total number of moles of the diamine-derived unit(s) (A2b).

[0072] The respective structural units of the polyamide resin (A2) and their ratios can be calculated from the charge ratios when preparing the polyamide resin (A2) or measured by the NMR method. For the NMR method, the same method as described for the polyamide resin (A2) can be used.

[0073] The dicarboxylic acid-derived component units of the polyamide resin (A2) may include component units derived from a biomass-derived dicarboxylic acid, and the diamine-derived component units may include component units derived from a biomass-derived diamine. The polyamide resin (A2) may also be a biomass-derived polyamide resin (A2) obtained by polymerizing raw materials including a biomass-derived raw material.

[0074] Specific examples of the polyamide resin (A2) include polyamide 6I6T.

[0075] The polyamide resin (A2) can be produced by the same method as that for the polyamide resin (A1).

[0076] The content of polyamide resin (A2) is preferably 3% by mass or more and 25% by mass or less, and more preferably 5% by mass or more and 20% by mass or less, based on the total mass of polyamide resin (A1) and polyamide resin (A2). A content of 3% by mass or more further reduces the crystallinity of the polyamide resin composition, thereby further increasing the flexibility of the resin workpiece and further suppressing cracking at low temperatures. Furthermore, a content of 25% by mass or less allows a sufficient amount of semi-oriented metallic polyamide resin (A1) to be contained in the polyamide resin composition, thereby further increasing the mechanical strength (tensile strength and flexural strength) of the resin workpiece containing the polyamide resin composition.

[0077] The content of the polyamide resin (A2) is preferably from 2 to 20% by mass, more preferably from 2 to 15% by mass, and even more preferably from 2 to 10% by mass, relative to the total mass of the polyamide resin composition.

[0078] (Physical Properties) The polyamide resin (A2) preferably has a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of more than 70°C and not more than 145°C, more preferably from 75°C to 130°C, and even more preferably from 80°C to 125°C.

[0079] The polyamide resin (A2) preferably has an intrinsic viscosity [η] of 0.4 dL / g or more and 1.6 dL / g or less, more preferably 0.5 dL / g or more and 1.2 dL / g or less, measured in 96.5% sulfuric acid at 25° C. The intrinsic viscosity [η] of the polyamide resin (A2) can be measured in the same manner as the intrinsic viscosity [η] of the polyamide resin (A1).

[0080] 1-3. Halogen-based flame retardants (B) In this embodiment, the polyamide resin composition contains a halogenated flame retardant (B). The halogenated flame retardant (B) can impart flame retardancy to the polyamide resin composition and a resin part containing the same. In this specification, the term "halogenated flame retardant" refers to a halogen-containing compound that can impart flame retardancy to the polyamide resin composition. The halogenated flame retardant (B) preferably contains at least one of brominated polystyrene and polybrominated styrene, and more preferably contains brominated polystyrene.

[0081] The content of the halogen-based flame retardant (B) is 21.5% by mass or more and 35.0% by mass or less, preferably 22% by mass or more and 33% by mass or less, and more preferably 22.5% by mass or more and 33% by mass or less, based on the total mass of the thermoplastic resin contained in the polyamide resin composition. A content of 21.5% by mass or more can further enhance the flame retardancy of the polyamide resin composition and a resin workpiece containing the same. Furthermore, a content of 33% by mass or less can further enhance the tracking resistance of the polyamide resin composition and a resin workpiece containing the same.

[0082] When the endothermic filler (C) described below is a phosphinate compound, the content of the halogen-based flame retardant (B) is preferably 9% by mass or more and 20% by mass or less, and more preferably 10% by mass or more and 15% by mass or less. Furthermore, when the endothermic filler (C) is a phosphinate compound, the content of the halogen-based flame retardant (B) is preferably 22% by mass or more and 30% by mass or less, and more preferably 22.5% by mass or more and 28% by mass or less, based on the total mass of the thermoplastic resin contained in the polyamide resin composition.

[0083] When the endothermic filler (C) is a borate compound, the content of the halogen-based flame retardant (B) is preferably from 10 to 20% by mass, and more preferably from 10 to 15% by mass. When the endothermic filler (C) described below is a borate compound, the content of the halogen-based flame retardant (B) is preferably from 25 to 35% by mass, more preferably from 28 to 34% by mass, and even more preferably from 30 to 33% by mass, based on the total mass of the thermoplastic resin contained in the polyamide resin composition.

[0084] The phosphinate compound can impart flame retardancy to the polyamide resin composition and the resin part containing the same, so that even if the content of the halogen-based flame retardant (B) is reduced, the polyamide resin composition and the resin part containing the same can exhibit sufficient flame retardancy.

[0085] The content of the halogen-based flame retardant (B) is preferably 20% by mass or more and 30% by mass or less, based on the total mass of the thermoplastic resin contained in the polyamide resin composition, when the scaly or plate-like inorganic particles (E) described below are mica particles, and is preferably 20% by mass or more and 40% by mass or less, based on the total mass of the thermoplastic resin, when the inorganic particles (E) are glass flakes. Since mica particles and glass flakes have different electrical resistances, differences arise in the tracking resistance of the polyamide resin composition when mixed with the resin. Glass flakes, which have higher electrical resistance, tend to have higher tracking resistance than mica, so a larger amount of the halogen-based flame retardant, which reduces tracking resistance, can be added.

[0086] The content of the halogen-based flame retardant (B) is preferably 20% by mass or more and 35% by mass or less, and more preferably 20.5% by mass or more and 31% by mass or less, based on the total mass of the polyamide resin composition. A content of 20% by mass or more can further enhance the flame retardancy and tracking resistance of the polyamide resin composition and a resin workpiece containing the same. Furthermore, a content of 35% by mass or less can further enhance the tracking resistance of the polyamide resin composition and a resin workpiece containing the same.

[0087] 1-4. Endothermic filler (C) In this embodiment, the polyamide resin composition contains an endothermic filler (C). In this specification, the endothermic filler (C) refers to an inorganic filler that absorbs heat generated during discharge, etc. The endothermic filler (C) is preferably an inorganic compound that absorbs heat and causes its own decomposition reaction.

[0088] The endothermic filler (C) may be, for example, a phosphinate compound, zinc borate (xZnO·yB2O3·zH2O (where (x, y, z) may be any of (2,3,0), (4,1,0), (1,2,0), (1,1,0), (3,2,0), (2,3,3.5), (2,3,4), (2,3,5.5), (2,2,3), or (4,1,1), and may be any of (2,3,0), (4,1,0), (1,2,0), ( Preferred are (1,1,0) and (3,2,0) (i.e., anhydrous zinc borate is preferred), with (2,3,0) being more preferred), borate compounds such as magnesium borate, calcium borate, and aluminum borate, magnesium hydroxide, aluminum phosphate, aluminum oxide (alumina), transition alumina, boehmite (aluminum oxide monohydrate), aluminum silicate, and aluminum hydroxide. Of these, preferred are phosphinate compounds and borate compounds.

[0089] The phosphinate compound is, for example, a compound represented by the following formula (I) or formula (II).

[0090] [ka]

[0091] In formula (I) and formula (II), R 1 and R 2 R are each independently a linear or branched alkyl or aryl group having 1 to 6 carbon atoms. 3 is a linear or branched alkylene group having from 1 to 10 carbon atoms, an arylene group having from 6 to 10 carbon atoms, an alkylarylene group having from 6 to 10 carbon atoms, or an arylalkylene group having from 6 to 10 carbon atoms. M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K, and / or a protonated nitrogen base. m, n, and x are each independently an integer of 1 to 4.

[0092] Specific examples of the phosphinate compound include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, and calcium methanedi(methylphosphinate). Methane di(methylphosphinate), magnesium methane di(methylphosphinate), aluminum methane di(methylphosphinate), zinc methane di(methylphosphinate), calcium benzene-1,4-(dimethylphosphinate), magnesium benzene-1,4-(dimethylphosphinate), aluminum benzene-1,4-(dimethylphosphinate), zinc benzene-1,4-(dimethylphosphinate), calcium methylphenylphosphinate, magnesium methylphenylphosphinate, aluminum methylphenylphosphinate, zinc methylphenylphosphinate, calcium diphenylphosphinate, magnesium diphenylphosphinate, aluminum diphenylphosphinate, zinc diphenylphosphinate, etc. Among these, calcium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, aluminum diethylphosphinate, and zinc diethylphosphinate are preferred, with aluminum diethylphosphinate being more preferred.

[0093] The content of the endothermic filler (C) is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, based on the total mass of the polyamide resin composition. By setting the content at 0.5% by mass or more, the tracking resistance of the polyamide resin composition and the resin workpiece containing the same can be more sufficiently improved. The upper limit of the content is not particularly limited, but is, for example, 15.0% by mass, preferably 10.0% by mass.

[0094] When the endothermic filler (C) is a phosphinate compound, the content of the endothermic filler (C) is preferably 0.5% by mass or more and 2.0% by mass or less, more preferably 0.5% by mass or more and 1.5% by mass or less, and more preferably 0.5% by mass or more and 1.2% by mass or less, relative to the total mass of the polyamide resin composition. When the content is 0.5% by mass or more, the tracking resistance of the polyamide resin composition and the resin workpiece containing the same can be more sufficiently improved.

[0095] Furthermore, by making the content 2.0% by mass or less, the heat shock resistance of the resin member can be improved. The reason for this is believed to be as follows.

[0096] The phosphinate compound thermally decomposes to produce phosphoric acid due to shear heat generated during kneading of the polyamide resin composition and heating to melt the polyamide resin composition during molding. Therefore, during the production of the polyamide resin composition and the production of the resin part, hydrolysis of the polyamide resin (A1) may occur, resulting in a decrease in the molecular weight of the polyamide resin (A1). As a result, the mechanical strength of the resin part containing the polyamide resin composition is reduced, and it is thought that stress generated in the resin part when the environmental temperature changes from high to low may cause cracks in the resin part.

[0097] For these reasons, when the endothermic filler (C) is a phosphinate compound, the heat shock resistance can be improved by setting the content of the endothermic filler (C) to 2.0 mass % or less.

[0098] When the endothermic filler (C) is zinc borate, the content of the endothermic filler (C) is preferably 1.5% by mass or more and 15% by mass or less, and more preferably 2.0% by mass or more and 10% by mass or less, relative to the total mass of the polyamide resin composition. A content of 1.5% by mass or more can more sufficiently improve the heat resistance and tracking resistance of the polyamide resin composition and the resin workpiece containing the same. Furthermore, a content of 15% by mass or less can further increase the polyamide content, thereby improving the mechanical strength (tensile strength and flexural strength) of the resin workpiece.

[0099] 1-5. Fibrous reinforcement (D) In the present embodiment, the polyamide resin composition preferably contains a fibrous reinforcing material (D). When the polyamide resin composition contains a fibrous reinforcing material (D), the mechanical strength of the resin member can be increased.

[0100] The type of fibrous reinforcing material (D) is not particularly limited, and examples thereof include glass fiber, carbon fiber, wollastonite, potassium titanate whisker, calcium carbonate whisker, aluminum borate whisker, magnesium sulfate whisker, sepiolite, xonotlite, zinc oxide whisker, milled fiber, cut fiber, wholly aromatic polyamide fiber (e.g., polyparaphenylene terephthalamide fiber, polymetaphenylene terephthalamide fiber, polyparaphenylene isophthalamide fiber, polymetaphenylene isophthalamide fiber, and fiber obtained from a condensate of diaminodiphenyl ether with terephthalic acid or isophthalic acid), boron fiber, liquid crystal polyester fiber, etc. Among these, from the viewpoint of increasing the rigidity and heat resistance of a resin member containing a polyamide resin composition, glass fiber and carbon fiber are preferred, and glass fiber is more preferred.

[0101] The weight-average fiber diameter (Dw) of the fibrous reinforcing material (D) is, for example, 1 μm or more and 50 μm or less, and from the viewpoint of further improving the moldability of the polyamide resin composition and the mechanical strength of a resin member containing the polyamide resin, preferably 5 μm or more and 30 μm or less. The weight-average fiber length of the fibrous reinforcing material (D) is, for example, 500 μm or more and 10,000 μm or less, and preferably 700 μm or more and 5,000 μm or less.

[0102] The weight average fiber length and weight average fiber diameter of the fibrous reinforcing material (D) can be measured by the following method. 1) The polyamide resin composition is dissolved in a hexafluoroisopropanol / chloroform solution (0.1 / 0.9% by volume), and then filtered to obtain a filtrate. 2) The filtered material obtained in 1) is dispersed in water, and the fiber length (Li) and fiber diameter (di) of each of 300 randomly selected fibers are measured using an optical microscope (magnification: 50x). The number of fibers with fiber length Li is defined as qi, and the weight-average length (Lw) is calculated using the following formula, which is the average fiber length of the fibrous reinforcing material. Weight average length (Lw) = (Σqi × Li 2 ) / (Σqi×Li) Similarly, the number of fibers with a fiber diameter Di is taken as ri, and the weight average diameter (Dw) is calculated based on the following formula, and this is taken as the average fiber diameter of the fibrous reinforcing material. Weight average diameter (Dw)=(Σri×Di 2 ) / (Σri×Di)

[0103] The content of the fibrous reinforcing material (D) is preferably 10% by mass or more and 60% by mass or less, and more preferably 20% by mass or more and 55% by mass or less, based on the total mass of the polyamide resin composition. A content of 10% by mass or more can increase the tensile strength of a resin part containing the polyamide resin composition. Furthermore, a content of 60% by mass or less can prevent a decrease in the fluidity of the polyamide resin composition during insert molding.

[0104] 1-6. Scaly or plate-like inorganic particles (E) In the present embodiment, the polyamide resin composition contains scaly or plate-like inorganic particles (E) (hereinafter also simply referred to as "inorganic particles (E)").

[0105] In this specification, "scale-like" or "plate-like" inorganic particles refer to inorganic particles whose surface is composed of multiple flat surfaces and whose area when observed from a predetermined angle (when viewed in plan) is larger than the area when observed from an angle perpendicular to the observation direction. More specifically, in "scale-like" or "plate-like" inorganic particles, the projected area when viewed in plan from the direction in which the projected area is largest is preferably 10 times the projected area when viewed in plan from the direction perpendicular to the above direction.

[0106] Examples of materials for the inorganic particles (E) include glass, mica, kaolin, clay, alumina, etc. Specific examples of types of inorganic particles (E) include glass flakes, mica particles, etc. When the material for the inorganic particles (E) is mica, the mica is preferably white mica (muscovite). This is because white mica has high insulating properties among micas, and can therefore more sufficiently improve the tracking resistance of polyamide resin compositions and resin parts containing the same.

[0107] The average particle size of the inorganic particles (E) is preferably 50 μm or more and 600 μm or less, more preferably 100 μm or more and 600 μm or less. When the particle size is 50 μm or more, the particles are finely dispersed, improving surface smoothness and tracking resistance. The average particle size of the inorganic particles (E) can be measured by ashing the polyamide resin composition or the resin workpiece at 600°C in an air atmosphere using an electric furnace, photographing the residue using an SEM, and processing the resulting image. The thickness of at least five inorganic particles (E) can be measured, and the average value can be used as the average thickness.

[0108] The aspect ratio (particle size / thickness) of the inorganic particles (E) is preferably from 10 to 900, more preferably from 20 to 500. The thickness of the inorganic particles (E) refers to the shortest length from one surface of the inorganic particles (E) to the other surface opposite to the surface.

[0109] The average thickness of the inorganic particles (E) is preferably 0.5 μm or more and 10 μm or less, and more preferably 0.5 μm or more and 8 μm or less. The average thickness of the inorganic particles (E) can be measured by ashing the polyamide resin composition or the resin member in an air atmosphere at 600°C using an electric furnace, photographing the residue using an SEM, and processing the resulting image. The thickness of at least five inorganic particles (E) can be measured, and the average value can be used as the average thickness.

[0110] The inorganic particles (E) are preferably surface-treated with a surface treatment agent such as an epoxy compound, an isocyanate compound, an organosilane compound, an organotitanate compound, or an organoborane. Surface-treated inorganic particles (E) can enhance the affinity between the inorganic particles (E) and the polyamide resin (A). This enhances the interfacial strength between the inorganic particles (E) and the polyamide resin (A), thereby reducing the difference in linear expansion coefficient between the resin member and the metal member and further improving the heat shock resistance of the resin member. The surface treatment agent is preferably an epoxy compound, an isocyanate compound, or an organosilane compound.

[0111] Examples of commercially available inorganic particles (E) include glass flakes (Fleca REFG-315, Fleca REFG-312, Fleca REFG-301, all manufactured by Nippon Sheet Glass Co., Ltd.), mica particles (Repco Mica M-60, Repco Mica M-200, Repco Mica M-200HG, Repco Mica M-400, all manufactured by Repco Corporation), and the like.

[0112] The content of the inorganic particles (E) is preferably 10% by mass or more and 40% by mass or less, and more preferably 15% by mass or more and 30% by mass or less, based on the total mass of the polyamide resin composition. When the content is 10% by mass or more, the smoothness of the surface of a resin workpiece containing the polyamide resin composition can be further increased, and the tracking resistance of the polyamide resin composition and the resin workpiece containing the same can be further improved.

[0113] The total mass of the fibrous reinforcing material (D) and the inorganic particles (E) is preferably 20% by mass or more and 65% by mass or less, and more preferably 25% by mass or more and 60% by mass or less, based on the total mass of the polyamide resin composition.

[0114] The ratio of the content of the inorganic particles (E) to the total mass of the fibrous reinforcing material (D) and the inorganic particles (E) is preferably 0.10 or more and 0.50 or less, and more preferably 0.15 or more and 0.45 or less. When the ratio is 0.10 or more, the smoothness of the surface of the resin workpiece can be further improved, and the tracking resistance can be more sufficiently improved. Furthermore, when the ratio is 0.50 or less, the proportion of the fibrous reinforcing material (D) can be increased, and the mechanical strength of the resin workpiece can be further improved.

[0115] 1-7.Other ingredients The polyamide resin composition may contain other known components.

[0116] Examples of other components include flame retardant aids, nucleating agents, lubricants, polyolefin resins, colorants, heat stabilizers, corrosion resistance improvers, anti-drip agents, ion scavengers, elastomers (rubbers), antistatic agents, mold release agents, antioxidants (phenols, amines, sulfur compounds, phosphorus compounds, etc.), heat stabilizers other than those mentioned above (lactone compounds, vitamin E compounds, hydroquinones, etc.), light stabilizers (benzotriazoles, triazines, benzophenones, benzoates, hindered amines, oxanilides, etc.), and the like.

[0117] (Flame retardant synergist) Examples of the flame retardant aid include metal oxides and metal hydroxides, and specifically, zinc stannate, iron oxide, zinc oxide, and tin oxide are preferred.

[0118] The content of the flame retardant aid is preferably 0.5% by mass or more and 5.0% by mass or less, and more preferably 1.0% by mass or more and 3.0% by mass or less, based on the total mass of the polyamide resin composition.

[0119] (nucleating agent) The nucleating agent can promote the crystallization of the polyamide resin (A), thereby further increasing the tensile strength and elastic modulus of the resin member.

[0120] Examples of nucleating agents include metal salt compounds such as sodium 2,2-methylenebis(4,6-di-t-butylphenyl)phosphate, aluminum tris(pt-butylbenzoate), and stearates; sorbitol compounds such as bis(p-methylbenzylidene)sorbitol and bis(4-ethylbenzylidene)sorbitol; and inorganic substances such as talc, calcium carbonate, and hydrotalcite. Among these, talc is preferred from the viewpoint of further increasing the crystallinity of the resin member. These nucleating agents may be used alone or in combination.

[0121] Talc generally contains hydrous magnesium silicate (SiO2: 58-64%, MgO: 28-32%, Al2O3: 0.5-5%, Fe2O3: 0.3-5%) as its main component. The average particle size of the talc is not particularly limited, but is preferably 1-15 μm. When the average particle size of the talc is within the above range, the talc can be easily dispersed in the polyamide resin (A) without impairing the fluidity of the polyamide resin composition. From the same viewpoint, the average particle size of the talc is more preferably 1-7.5 μm. The average particle size of the talc can be measured by a laser diffraction method, for example, using a Shimadzu particle size distribution analyzer (SALD-2000A) manufactured by Shimadzu Corporation.

[0122] The content of the nucleating agent is preferably 0.10 parts by mass or more and 5.00 parts by mass or less, and more preferably 0.10 parts by mass or more and 3.00 parts by mass or less, relative to the total mass of the polyamide resin composition. When the content of the nucleating agent is within the above range, the crystallinity of the resin member is easily increased sufficiently, and sufficient mechanical strength is easily obtained.

[0123] (sliding material) The lubricant improves the injection flowability of the polyamide resin composition and improves the appearance of the resulting resin part. The lubricant can be a metal salt of a fatty acid, such as a metal salt of an oxycarboxylic acid or a metal salt of a higher fatty acid.

[0124] The hydroxycarboxylic acid constituting the hydroxycarboxylic acid metal salt may be an aliphatic hydroxycarboxylic acid or an aromatic hydroxycarboxylic acid. Examples of the aliphatic hydroxycarboxylic acid include aliphatic hydroxycarboxylic acids having 10 to 30 carbon atoms, such as α-hydroxymyristic acid, α-hydroxypalmitic acid, α-hydroxystearic acid, α-hydroxyeicosanoic acid, α-hydroxydocosanoic acid, α-hydroxytetraeicosanoic acid, α-hydroxyhexaeicosanoic acid, α-hydroxyoctaeicosanoic acid, α-hydroxytriacontanoic acid, β-hydroxymyristic acid, 10-hydroxydecanoic acid, 15-hydroxypentadecanoic acid, 16-hydroxyhexadecanoic acid, 12-hydroxystearic acid, and ricinoleic acid. Examples of the aromatic hydroxycarboxylic acid include salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, gallic acid, mandelic acid, and trovic acid.

[0125] Examples of the metal constituting the metal oxycarboxylic acid salt include alkali metals such as lithium, and alkaline earth metals such as magnesium, calcium, and barium.

[0126] Of these, the metal oxycarboxylic acid salt is preferably a metal salt of 12-hydroxystearic acid, and more preferably magnesium 12-hydroxystearate and calcium 12-hydroxystearate.

[0127] Examples of the higher fatty acids that constitute the higher fatty acid metal salts include higher fatty acids having 15 to 30 carbon atoms, such as stearic acid, oleic acid, behenic acid, behenic acid, and montanic acid.

[0128] Examples of metals constituting the above higher fatty acid metal salts include calcium, magnesium, barium, lithium, aluminum, zinc, sodium, and potassium.

[0129] Of these, the higher fatty acid metal salts are preferably calcium stearate, magnesium stearate, barium stearate, calcium behenate, sodium montanate, and calcium montanate.

[0130] The content of the lubricant is preferably 0.01% by mass or more and 1.30% by mass or less relative to the total mass of the polyamide resin composition. When the content of the lubricant is 0.01% by mass or more, the fluidity during molding tends to be improved, and the appearance of the obtained molded product tends to be improved. When the content of the lubricant is 1.30% by mass or less, gas due to decomposition of the lubricant is unlikely to be generated during molding, and the appearance of the product tends to be good.

[0131] (Polyolefin resin) Examples of polyolefin resins include ethylene polymers, propylene polymers, butene polymers, and copolymers of these olefins (e.g., ethylene-α-olefin copolymers), etc. Among these, ethylene polymers are preferred.

[0132] Examples of the α-olefin other than ethylene in the ethylene-α-olefin copolymer include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, etc. Among these, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene are preferred.

[0133] The polyolefin resin preferably includes a modified polyolefin resin. Specifically, the polyolefin resin preferably includes a modified polyolefin resin having a polyolefin unit and a functional group structural unit. The modified polyolefin resin can be obtained by modifying a polyolefin resin before modification with a compound containing a functional group structural unit.

[0134] Examples of the functional group structural unit include functional groups containing heteroatoms. Examples of functional groups containing heteroatoms include carboxylic acid groups (including carboxylic acid anhydride groups), ester groups, ether groups, aldehyde groups, and ketone groups. Among these, carboxylic acid groups (including carboxylic acid anhydride groups) are preferred. That is, the modified polyolefin resin is preferably modified with an unsaturated carboxylic acid or its derivatives.

[0135] Examples of compounds containing a carboxylic acid group include α,β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, and phthalic acid. Examples of compounds containing a carboxylic acid anhydride group include dicarboxylic acid anhydrides having an α,β-unsaturated bond such as maleic anhydride, itaconic anhydride, and phthalic anhydride. Of these, maleic anhydride is preferred.

[0136] The content of the functional group structural unit (modification amount) of the modified polyolefin resin is preferably 0.1% by mass or more and 5.0% by mass or less, more preferably 0.2% by mass or more and 3.0% by mass or less, and even more preferably 0.5% by mass or more and 1.5% by mass or less. When the content of the functional group structural unit is within the above range, the impact resistance and elongation of the resin composition tend to be improved.

[0137] The content (modification amount) of the functional group structural unit of the modified polyolefin resin can be calculated from the charge ratio when preparing the modified polyolefin resin, or can be measured by the NMR method. For the NMR method, the same method as described for the polyamide resin (A) can be used.

[0138] The modified polyolefin resin is obtained by graft-modifying an unmodified polyolefin resin with a compound containing a functional group structural unit.

[0139] Graft modification can be carried out by various conventionally known methods. For example, it may be carried out by a melt modification method in which the polyolefin resin before modification is melted using an extruder and a graft monomer is added to carry out graft copolymerization, or it may be carried out by a solution modification method in which the polyolefin resin before modification is dissolved in a solvent and a graft monomer is added to carry out graft copolymerization. In either case, it is preferable to carry out the reaction in the presence of a radical initiator in order to efficiently graft copolymerize the graft monomer.

[0140] The content of the polyolefin resin is preferably 2% by mass or more and 10% by mass or less, more preferably 3% by mass or more and 8% by mass or less, and even more preferably 3% by mass or more and 6% by mass or less, relative to the total mass of the polyamide resin composition.

[0141] (coloring agent) The colorant imparts a desired color tone to the resin member. The colorant is not particularly limited, but may be a pigment. Examples of the pigment include inorganic pigments such as carbon black, alumina, titanium oxide, chromium oxide, iron oxide, zinc oxide, and barium sulfate, and organic pigments such as azo pigments, phthalocyanine pigments, quinacridone pigments, perylene pigments, anthraquinone pigments, thioindigo pigments, and indanthrene pigments.

[0142] The content of the colorant is preferably 0.01% by mass or more and 5.00% by mass or less, and more preferably 0.10% by mass or more and 2.00% by mass or less, based on the total mass of the polyamide resin composition.

[0143] 1-8. Method for producing polyamide resin composition The polyamide resin composition can be produced by a known resin blending method, such as mixing the polyamide resin (A), halogen-based flame retardant (B), phosphinate compound (C), fibrous reinforcing material (D), inorganic particles (E), and other components as needed, using a Henschel mixer, V-blender, ribbon blender, or tumbler blender, or by melt-blending the mixture in a single-screw extruder, multi-screw extruder, kneader, or Banbury mixer, followed by granulation or pulverization. The melting temperature during melt-blending is preferably at least 10°C above the melting point (Tm) of the polyamide resin (A1) and not more than 20°C above the melting point (Tm).

[0144] 2.Metal resin composite The metal resin composite according to this embodiment includes a metal member and a resin member that is composited with the metal member and includes the polyamide resin composition described above.

[0145] 2-1.Resin parts The resin member contains the polyamide resin composition described above. The proportion of the polyamide resin composition relative to the total mass of the resin member is preferably 50.00 mass% or more, more preferably 60.00 mass% or more, and even more preferably 70.00 mass% or more. The upper limit of the proportion of the polyamide resin composition relative to the total mass of the resin member is not particularly limited, but may be 100.00 mass% or less, or may be 90.00 mass% or less, or may be 80.00 mass% or less.

[0146] 2-2.Metallic parts The metal member may be made of any metal, and the material and shape thereof are not particularly limited. For example, the metal member may be made of iron, copper, nickel, gold, silver, platinum, cobalt, zinc, lead, tin, titanium, chromium, aluminum, magnesium, manganese, or an alloy such as stainless steel, brass, or phosphor bronze.

[0147] These materials can be selected depending on the application of the metal-resin composite. For example, when thermal conductivity is required, aluminum, aluminum alloys, magnesium, magnesium alloys, copper, and copper alloys are preferred, with copper and copper alloys being more preferred. Furthermore, when weight reduction and strength are required, aluminum, aluminum alloys, magnesium, and magnesium alloys are preferred.

[0148] The metal member preferably has a surface roughened. When the surface of the metal member is roughened, the polyamide resin composition melted or softened during molding penetrates into recesses formed on the surface of the metal member and solidifies, thereby firmly bonding the resin member containing the polyamide resin composition to the metal member. The method of roughening is not particularly limited, and the surface may be roughened by chemical treatment such as immersion in a treatment solution containing a base or acid or etching, or physical treatment such as laser or blasting.

[0149] The surface of the roughened metal member preferably has a center-to-center distance (pitch) of 5 nm to 500 μm. When the center-to-center distance of the multiple protrusions is 5 nm or more, the recesses between the protrusions are appropriately large, making it easier for the resin member to penetrate into the recesses during bonding, thereby further improving the bonding strength between the metal member and the resin member. Furthermore, when the center-to-center distance of the multiple protrusions is 500 μm or less, the recesses are not too large, further suppressing the formation of gaps at the metal-resin interface of the metal-resin composite, thereby further improving airtightness. From the same perspective, the center-to-center distance of the multiple protrusions is more preferably 5 μm to 250 μm. The center-to-center distance of the multiple protrusions is the average value of the distances between the centers of one protrusion and the adjacent protrusion.

[0150] The center-to-center distance of the multiple convex portions can be measured by removing the resin member from the metal-resin composite by mechanical peeling, solvent washing, or the like, and observing the surface of the exposed metal member using an electron microscope or laser microscope, or a surface roughness measuring device.

[0151] Specifically, when the center-to-center distance between the multiple protrusions is less than 0.5 μm, they can be observed using an electron microscope, and when the center-to-center distance between the multiple protrusions is 0.5 μm or more, they can be observed using a laser microscope or surface roughness measuring device. For example, in a photograph of the surface of a metal part taken with an electron microscope or laser microscope, 50 random protrusions are selected and the center-to-center distance between each of these protrusions is measured. All of the measured center-to-center distances between the protrusions are then added up and divided by 50 (average) to determine the "center-to-center distance between the multiple protrusions."

[0152] The average value of the ten-point average roughness (Rz) of the roughened surface of the metal member over an evaluation length of 4 mm is not particularly limited, but is preferably greater than 2 μm, more preferably greater than 2 μm and not greater than 50 μm, and even more preferably greater than 2.5 μm and not greater than 45 μm.

[0153] The average value of the ten-point mean roughness (Rz) can be measured in accordance with JIS B0601 (ISO 4287). Specifically, the ten-point mean roughness (Rz) is measured on a total of six straight line sections, including three arbitrary parallel straight line sections and three arbitrary perpendicular straight line sections, and the average of these is taken as the average Rz value.

[0154] The mean length of the roughness curve element (RSm) of the roughened surface of the metal member is preferably 0.5 μm or more and 500 μm or less. In particular, from the viewpoint of further increasing the bonding strength, it is preferable that the center-to-center distance between multiple convex portions is less than 0.5 μm and the mean length of the roughness curve element (RSm) is 0.5 μm or more and 500 μm or less. The mean length of the roughness curve element can also be measured according to JIS B0601 (ISO 4287) as described above.

[0155] 3.Metal-resin composite manufacturing method The method for producing a metal resin composite is not particularly limited, and may include, for example, the steps of (1) preparing a metal member, (2) placing the metal member in a mold and injecting a molten polyamide resin composition into the mold, and (3) cooling the polyamide resin composition. The step (1) of preparing a metal member may include a step of roughening the surface of the metal member.

[0156] 3-1.Preparing metal parts First, the above-described metal member is prepared. At this time, at least a part of the surface of the metal member may be roughened, or a metal member having an uneven structure on at least a part of the surface may be prepared.

[0157] The method for roughening the surface of a metal member is not particularly limited. For example, a method using laser processing, a method of immersing a metal member in an aqueous solution of an inorganic base such as NaOH or an aqueous solution of an inorganic acid such as HCl or HNO3, a method of treating a metal member by anodization, a displacement crystallization method in which etching is performed with an acid-based etching agent (preferably an acid-based etching agent aqueous solution containing an inorganic acid, ferric ions, cupric ions, and if necessary, manganese ions, aluminum chloride hexahydrate, sodium chloride, etc.), a method of immersing a metal member in an aqueous solution of hydrazine hydrate, ammonia, a water-soluble amine compound, etc., and a hot water treatment method can be used.

[0158] 3-2.Insert molding Next, a metal member is placed in a mold, and the molten polyamide resin composition is injected into the mold to fill it, thereby combining (integrating) the softened or molten polyamide resin composition with the prepared metal member.

[0159] Specifically, the prepared metal member is first placed in a cavity (space) within an injection mold. Then, the polyamide resin composition is injected and filled into the cavity of the mold so that at least a portion of the polyamide resin composition contacts the metal member. This allows the injected molten polyamide resin composition to come into contact with the surface of the metal member. The temperature of the injection mold at this time is not particularly limited as long as it is a temperature at which the polyamide resin composition can be melted to a state suitable for injection molding, and can be, for example, 100 to 350°C.

[0160] As the mold, a known injection molding mold, for example, a mold for high speed heat cycle molding (RHCM, heat & cool molding) or a core back mold for foam molding can be used.

[0161] 3-3. Cooling Thereafter, the polyamide resin composition that has come into contact with the surface of the metal member is cooled and solidified, thereby obtaining a metal resin composite in which a resin member containing the polyamide resin composition is composited with the metal member.

[0162] 4.Applications The above-mentioned metal-resin composite is suitably used in various applications where metal-resin composites are being applied or where their application is being considered.

[0163] Examples of such applications include vehicle structural parts, vehicle mounted items, housings for electronic devices, housings for home appliances, structural parts, machine parts, various automobile parts, electronic device parts, household goods applications such as furniture and kitchen utensils, medical equipment, building material parts, other structural parts, and exterior parts.

[0164] More specifically, examples of the above applications include, in the case of vehicles, instrument panels, console boxes, door handles, door trim, shift levers, pedals, glove boxes, bumpers, hoods, fenders, trunks, doors, roofs, pillars, seats, steering wheels, bus bars, terminals, motors, power conversion devices (inverters, converters), ECU boxes, electrical components, engine peripheral parts, drivetrain and gear peripheral parts, intake and exhaust system parts, and cooling system parts, etc. Precision electronic components also include connectors, relays, gears, etc.

[0165] Furthermore, the metal-resin composite can be used in various home appliances, such as refrigerators, washing machines, vacuum cleaners, microwave ovens, air conditioners, lighting equipment, electric water heaters, televisions, clocks, ventilation fans, projectors, speakers, and other home appliances, as well as electronic information devices such as personal computers, mobile phones, smartphones, digital cameras, tablet PCs, portable music players, portable game consoles, chargers, and batteries, by combining the high thermal conductivity of the copper member with the insulating properties of the resin member.

[0166] Other application examples include components for lithium-ion secondary batteries and robots.

[0167] For example, the metal-resin composite can be used in a bus bar unit of a mobile body (vehicle) such as an automobile.

[0168] 1 is a schematic diagram showing an exemplary embodiment of the metal-resin composite as a busbar unit. Busbar unit 100 includes busbar 110, which is a conductive metal member (e.g., a copper metal member) and serves as a conductor for supplying current to each member, and holding member 120, which is the resin member described above and serves as a protective member for protecting busbar 110.

[0169] Of the surfaces of busbar 110, which is a metal member, the surface that comes into contact with holding member 120 is roughened, and holding member 120, which is a resin member (a resin member including a molded body of a polyamide resin composition), is joined to the roughened surface.

[0170] The bus bar unit 100 can be used to electrically connect, via the bus bar 110, a motor of a moving object and an inverter that controls the power supplied to the motor.

[0171] 2 is a diagram showing an exemplary configuration of a moving body (vehicle) having the busbar unit 100. The moving body 200 has a body 210, a power supply 220 such as a secondary battery that supplies power to drive the body 210, and a drive unit 230 that drives the body 210 with the power supplied from the power supply 220.

[0172] Drive unit 230 has inverter 232 that controls power (current) from power supply 220, motor 234 that rotates by receiving the power controlled by inverter 232, and bus bar unit 100 that has bus bar 110 that connects inverter 232 and motor 234. Motor 234 is housed in motor case 236 together with reducer 235 that converts the rotational speed obtained by motor 234 into a rotational speed for driving machine body 210. Bus bar unit 100 is attached to motor case 236, and bus bar 110 communicates from the inside to the outside of motor case 236 via bus bar unit 100.

[0173] A coolant (coolant oil) for cooling the motor 234 is stored inside the motor case 236. The connection between the bus bar unit 100 and the motor case 236 is sealed with a sealing member such as an O-ring, thereby preventing oil from leaking from the inside of the motor case 236 to the outside.

[0174] In conventional busbar units, oil can leak from between the busbar and the protective member due to poor airtightness between the busbar and the protective member. In contrast, in this embodiment, holding member 120, which is made of a resin member containing the above-mentioned molded article of the polyamide resin composition, is joined with high airtightness to busbar 110, which is a conductive metal member (e.g., a copper metal member), thereby preventing oil leakage.

[0175] 2 shows an example in which the moving body 200 is a vehicle such as an automobile, but the moving body 200 is not particularly limited as long as it has a body and a drive unit and is capable of moving. For example, the moving body 200 may be a train, a ship, an airplane, a drone, a robot, or the like, in addition to vehicles such as an automobile, a motorcycle, and an electric bicycle. [Example]

[0176] The present invention will be described below with reference to examples, which should not be construed as limiting the scope of the present invention.

[0177] 1. Synthesis / preparation of materials 1-1. Synthesis of polyamide resin (A) <Polyamide resin (PA-1) (6T66)> 2800 g (24.1 mol) of 1,6-diaminohexane, 2184 g (13.2 mol) of terephthalic acid, 1572 g (10.8 mol) of adipic acid, and 5.67 g (5.4 × 10) of sodium hypophosphite monohydrate as a catalyst. -282.4 g (0.67 mol) of benzoic acid as a molecular weight modifier, and 409 ml of ion-exchanged water were placed in a 13.6 L autoclave and purged with nitrogen. Stirring was initiated at 190°C, and the internal temperature was raised to 250°C over 3 hours. At this time, the internal pressure of the autoclave was increased to 3.02 MPa. After the reaction was continued for 1 hour, the low-order condensate was discharged into the atmosphere through a spray nozzle installed at the bottom of the autoclave. The low-order condensate was then cooled to room temperature, pulverized to a particle size of 1.5 mm or less in a pulverizer, and dried at 110°C for 24 hours. 5440 g of a polyamide precursor was obtained, having a water content of 3000 ppm and an intrinsic viscosity [η] of 0.15 dL / g. The polyamide precursor was then dried and melt-polymerized using a twin-screw extruder at a cylinder temperature of 330°C to obtain polyamide resin (PA-1).

[0178] The resulting polyamide resin (PA-1) had an intrinsic viscosity [η] of 0.8 dl / g, a melting point (Tm) of 310°C, a glass transition temperature (Tg) of 85°C, and a heat of fusion of 44 J / g. The resulting polyamide resin (PA-1) contained 55 mol% of terephthalic acid-derived units among dicarboxylic acid-derived units, and 45 mol% of adipic acid-derived units. The diamine-derived units contained 1,6-diaminohexane-derived units, which accounted for 100 mol% of the diamine-derived units.

[0179] <Polyamide resin (PA-2) (6T66)> 2800 g (24.1 mol) of 1,6-diaminohexane, 2184 g (13.2 mol) of terephthalic acid, 1572 g (10.8 mol) of adipic acid, and 5.67 g (5.4 × 10) of sodium hypophosphite monohydrate as a catalyst. -236.5 g (0.30 mol) of benzoic acid as a molecular weight modifier, and 409 ml of ion-exchanged water were placed in a 13.6 L autoclave and purged with nitrogen. Stirring was initiated at 190°C, and the internal temperature was raised to 250°C over 3 hours. At this time, the internal pressure of the autoclave was increased to 3.02 MPa. After the reaction was continued for 1 hour, the low-order condensate was discharged into the atmosphere through a spray nozzle installed at the bottom of the autoclave. The low-order condensate was then cooled to room temperature, pulverized to a particle size of 1.5 mm or less, and dried at 110°C for 24 hours. 5440 g of a polyamide precursor was obtained, having a water content of 3000 ppm and an intrinsic viscosity [η] of 0.15 dL / g. The polyamide precursor was then dried and melt-polymerized using a twin-screw extruder at a cylinder temperature of 330°C to obtain polyamide resin (PA-2).

[0180] The resulting polyamide resin (PA-2) had an intrinsic viscosity [η] of 1.0 dl / g, a melting point (Tm) of 310°C, a glass transition temperature (Tg) of 85°C, and a heat of fusion of 44 J / g. The resulting polyamide resin (PA-1) had a composition in which the content of component units derived from terephthalic acid among component units derived from dicarboxylic acid was 55 mol% and the content of component units derived from adipic acid was 45 mol%. The content of component units derived from 1,6-diaminohexane among component units derived from diamine was 100 mol%.

[0181] 1-2. Synthesis of polyamide resin (A2) <Polyamide resin (PA-3) (6I6T)> 2,800 g (24.1 mol) of 1,6-diaminohexane, 1,196 g (7.2 mol) of terephthalic acid, 2,774 g (16.7 mol) of isophthalic acid, 36.6 g (0.30 mol) of benzoic acid, 5.7 g of sodium hypophosphite monohydrate, and 545 g of distilled water were placed in a 13.6 L autoclave and purged with nitrogen. Stirring was initiated at 190°C, and the internal temperature was raised to 250°C over 3 hours. At this time, the internal pressure of the autoclave was increased to 3.03 MPa. After the reaction was continued for 1 hour, the autoclave was vented to the atmosphere through a spray nozzle installed at the bottom, and the low-order condensation product was extracted. After cooling to room temperature, the low-order condensation product was pulverized in a pulverizer to a particle size of 1.5 mm or less and dried at 110°C for 24 hours. The resulting low-order condensate had a water content of 4100 ppm and an intrinsic viscosity [η] of 0.15 dl / g.

[0182] Next, this low-order condensate was placed in a tray-type solid-state polymerization reactor, and after nitrogen substitution, the temperature was raised to 180°C over approximately 1 hour and 30 minutes. The reaction was then allowed to proceed for 1 hour and 30 minutes, and the temperature was then lowered to room temperature. The intrinsic viscosity [η] of the resulting prepolymer was 0.20 dL / g. The resulting prepolymer was then melt-polymerized in a twin-screw extruder with a screw diameter of 30 mm and L / D = 36 at a barrel setting temperature of 330°C, a screw rotation speed of 200 rpm, and a resin feed rate of 6 kg / h to obtain a polyamide resin (PA-3).

[0183] The intrinsic viscosity [η] of the obtained polyamide resin (PA-3) was 0.54 dl / g, the melting point (Tm) was not measured, the glass transition temperature (Tg) was 125°C, and the heat of fusion (ΔH) was 0 J / g.

[0184] 1-3. Halogen-based flame retardants (B) Brominated polystyrene (HP-3010, manufactured by Albemarle) was used.

[0185] 1-4. Endothermic filler (C) C-1: Aluminum diethylphosphinate (OP-1230, Clariant) C-2: Zinc borate (Fire Brake 500, manufactured by US Borax, volume average particle size (D50): 9 μm)

[0186] 1-5. Fibrous reinforcement (D) D-1: Glass fiber (CS03JA FT789, manufactured by Owens Corning)

[0187] 1-6. Scaly or plate-like inorganic particles (E) E-1: White mica (Repco Mica M-200, manufactured by Repco Co., Ltd., average particle size 55 μm) E-2: White mica (Repco Mica M-60, manufactured by Repco Co., Ltd., average particle size 160 μm) E-3: Gold mica (Repco Mica S-200HG, manufactured by Repco Co., Ltd., average particle size 55 μm) E-4: Glass flakes (Freka REFG-315, manufactured by Nippon Sheet Glass Co., Ltd., average thickness 5 μm, average particle size 315 μm)

[0188] 1-7.Other ingredients 1-7-1. Coloring agents Carbon black was used.

[0189] 1-7-2.Polyolefin resin <Synthesis of modified polyolefin resin (PO-1)> A catalyst solution was prepared by adding 0.63 mg of bis(1,3-dimethylcyclopentadienyl)zirconium dichloride to a glass flask thoroughly purged with nitrogen, followed by 1.57 ml of a toluene solution of methylaluminoxane (Al; 0.13 mmol / L) and 2.43 ml of toluene. Next, 912 ml of hexane and 320 ml of 1-butene were introduced into a 2 L stainless steel autoclave thoroughly purged with nitrogen, and the temperature of the system was raised to 80 °C. Subsequently, 0.9 mmol of triisobutylaluminum and 2.0 ml of the catalyst solution prepared above (0.0005 mmol as Zr) were pressurized into the system with ethylene to initiate the polymerization reaction. The total pressure was maintained at 8.0 kg / cm2-G by continuously supplying ethylene, and the polymerization was carried out at 80 °C for 30 minutes. A small amount of ethanol was added to the system to terminate the polymerization, and the unreacted ethylene was then purged. The resulting solution was poured into a large excess of methanol to precipitate a white solid, which was collected by filtration and dried overnight under reduced pressure to obtain a white solid (ethylene-1-butene copolymer).

[0190] The ethylene content of the ethylene-1-butene copolymer was 81 mol %. The density was 0.860 g / cm 3 The MFR (ASTM D 1238, 190°C, 2.16 kg load) was 0.5 g / 10 min, and the melting point was 35°C.

[0191] 100 parts by mass of the obtained ethylene-1-butene copolymer was mixed with 1.0 part by mass of maleic anhydride and 0.04 part by mass of peroxide (Perhexyne 25B, NOF Corporation). The resulting mixture was melt-graft-modified in a twin-screw extruder set at 230°C to obtain a modified polyolefin resin.

[0192] The content (modification amount) of component units derived from maleic anhydride in the obtained modified polyolefin resin was 0.8 mass %. The density was 0.866 g / cm 3 The MFR was 0.27 g / 10 min.

[0193] <Modified Polyolefin (PO-2)> Maleic acid-modified SEBS (Tuftec M1913, manufactured by Asahi Chemicals Co., Ltd.)

[0194] 1-7-3.Sliding material Calcium montanate was used.

[0195] 1-7-4.Flame retardant synergists Flame retardant synergist 1: Hydrotalcite (NAOX-33, manufactured by Toda Kogyo Co., Ltd.) Flame retardant synergist 2: Sodium antimonate (SA-A, manufactured by Nippon Seiko Co., Ltd.)

[0196] 1-7-5. Nucleating Agent Talc (average particle size 6 μm) was used.

[0197] 2. Measurement The physical properties of each of the above resins were measured by the following methods.

[0198] <Melting point (Tm), glass transition temperature (Tg)> The melting point (Tm) and glass transition temperature (Tg) of polyamide resin (A) were measured using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.). Specifically, approximately 5 mg of polyamide resin was sealed in an aluminum pan for measurement and set in the differential scanning calorimeter. The polyamide resin was then heated from room temperature to 350°C at 10°C / min. To completely melt the resin, it was held at 350°C for 3 minutes and then cooled to 30°C at 10°C / min. After leaving it at 30°C for 5 minutes, it was heated a second time to 350°C at 10°C / min. The temperature (°C) of the endothermic peak during this second heating was taken as the melting point (Tm) of the polyamide resin, and the inflection point corresponding to the glass transition was taken as the glass transition temperature (Tg). The crystallization temperature of aliphatic polyamide resin (B) was determined as the temperature (°C) of the exothermic peak during the cooling process.

[0199] <Heat of fusion (ΔH)> The heat of fusion (ΔH) of the polyamide resin (A) was calculated from the area of ​​the exothermic peak of crystallization during the first heating process in accordance with JIS K 7122 (2012).

[0200] <Intrinsic viscosity [η]> The intrinsic viscosity [η] of the polyamide resin (A) was calculated based on the formula: [η] = ηSP / (C(1 + 0.205ηSP)) by dissolving 0.5 g of the polyamide resin in 50 ml of a 96.5% sulfuric acid solution, and measuring the flow time of the resulting solution at 25°C ± 0.05°C using an Ubbelohde viscometer. [η]: Intrinsic viscosity (dl / g) ηSP: Specific viscosity C: Sample concentration (g / dl) t: Number of seconds for sample solution to flow down (seconds) t0: Number of seconds the blank sulfuric acid flows (seconds) ηSP=(t-t0) / t0

[0201] <Amount of denaturation> The content (modification amount) (mass %) of component units derived from maleic anhydride in the modified polyolefin resin was measured by NMR under the following measurement conditions. Measurement equipment: Nuclear magnetic resonance equipment (ECP500 type, manufactured by JEOL Ltd.) Observation kernel: 13 C(125MHz) Sequence: Single pulse proton decoupling Pulse width: 4.7 μsec (45° pulse) Repeat Time: 5.5 seconds Accumulation count: 10,000 times or more Solvent: orthodichlorobenzene / deuterated benzene (volume ratio: 80 / 20) mixed solvent Sample concentration: 55mg / 0.6mL Measurement temperature: 120℃ Chemical shift reference value: 27.50 ppm

[0202] <density> The density of the modified polyolefin resin was measured at a temperature of 23°C using a density gradient tube in accordance with JIS K7112:1999.

[0203] <mfr> The MFR was measured in accordance with ASTM D1238 (2023) at 190°C under a load of 2.16 kg.

[0204] 3. Preparation of polyamide resin composition The above materials were mixed in a tumbler blender in the composition ratios (unit: parts by mass) shown in Tables 1 to 9, and melt-kneaded using a 30 mmφ vented twin-screw extruder at a cylinder temperature of 300 to 335°C. The kneaded mixture was then extruded into strands and cooled in a water bath. The strands were then taken up in a pelletizer and cut to obtain pellet-shaped polyamide resin compositions 1 to 44.

[0205] 4. Evaluation <Liquidity> Each polyamide resin composition was injected into a bar flow mold having a width of 10 mm and a thickness of 0.5 mm under the following conditions, and the flow length (mm) of the resin composition in the mold was measured. Injection molding machine: Tupearl TR40S3A (manufactured by Sodick Plastech Co., Ltd.) Injection pressure setting: 2000 kg / cm 2 Cylinder temperature setting: Polyamide resin melting point + 10°C Mold temperature: 120℃

[0206] <Tensile strength and gauge length elongation> Each polyamide resin composition was injection molded under the following conditions to obtain an ISO dumbbell-shaped test piece Type A having a thickness of 4.0 mm. Injection molding machine: EC75N (manufactured by Toshiba Machine Co., Ltd.) Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 160℃

[0207] The obtained test piece was left for 24 hours in a nitrogen atmosphere at a temperature of 23° C. Then, a tensile test was carried out in an atmosphere at a temperature of 23° C. in accordance with ISO 527 to measure the tensile strength and the gauge length elongation.

[0208] <Flexural strength, deflection, flexural modulus> Each polyamide resin composition was injection molded under the following molding conditions to obtain an ISO dumbbell-shaped test piece Type A having a thickness of 4.0 mm. Molding machine: EC75N-2A (Shibaura Machine Co., Ltd.) Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 120℃ The obtained test pieces were left for 24 hours in a nitrogen atmosphere at 23°C. Then, a bending test was carried out in an atmosphere of 23°C and 50% relative humidity using a bending tester (NTESCO AB5) with a span of 51 mm and a bending speed of 5 mm / min to measure the bending strength (MPa), deflection (mm), and bending modulus (MPa).

[0209] <Tracking resistance (CTI)> Each polyamide resin composition was molded using the following injection molding machine under the following molding conditions to obtain test pieces of 200 mm x 130 mm x 3 mm. Molding machine: EC75N-2A (manufactured by Toshiba Machine Co., Ltd.) Cylinder temperature: Melting point of polyamide resin + 10°C Mold temperature: 120℃

[0210] The comparative tracking index (CTI [V]), an index of tracking resistance, was measured for the obtained test specimens under the following conditions in accordance with IEC 60112 (2020). A higher CTI value indicates better tracking resistance. Test solution: Ammonium chloride (0.1% concentration) aqueous solution Testing machine: YST-1000V (Yamayo Testing Instruments Co., Ltd.)

[0211] <Flame retardancy> Each polyamide resin composition was injection molded under the following conditions to prepare 1 / 32 inch x 1 / 2 x 5 inch test pieces. Using the prepared test pieces, a vertical flame test was carried out in accordance with the UL94 standard (UL Test No. UL94 dated June 18, 1991) to evaluate flame retardancy. Molding machine: Tupearl TR40S3A (manufactured by Sodick Plastic Co., Ltd.) Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 120℃

[0212] <Heat shock resistance> An insert member (54 mm x 54 mm x 2 mm) made of S45C, as specified in JIS G4051:2016 (Carbon Steel for Machine Structures), was placed in a metal insert molding die attached to an injection molding machine (SE75EV, manufactured by Sumitomo Heavy Industries, Ltd.). The various polyamide resin compositions were then injection molded into the die under conditions of a cylinder set temperature of 320°C, a die temperature of 120°C, and an injection speed of 50 mm / sec to produce metal insert test specimens with a minimum resin thickness of 1 mm. These test specimens were subjected to a heat shock test using a thermal shock tester (manufactured by Espec Corporation), with one cycle consisting of a 30-minute hold at -40°C and a 30-minute hold at 160°C. The presence or absence of cracks was observed every five cycles, and the number of cycles until cracks occurred was measured. This measurement was performed five times for each test specimen, and the average number of cycles was calculated. When the calculated number of times is 0, it means that cracks occurred immediately after forming, and when it is 1 or more, it means that no cracks occurred immediately after forming.

[0213] The composition and evaluation results of each polyamide resin composition are shown in Tables 1 to 9. The numerical values ​​for the composition in Tables 1 to 9 represent parts by mass.

[0214] [Table 1]

[0215] [Table 2]

[0216] [Table 3]

[0217] [Table 4]

[0218] [Table 5]

[0219] [Table 6]

[0220] [Table 7]

[0221] [Table 8]

[0222] [Table 9]

[0223] From the results of polyamide resin compositions 1 to 11, polyamide resin compositions 16 to 25, and polyamide resin compositions 31 to 42, it was found that when the content of brominated polystyrene (B) is 21.5 mass% or more and 35.0 mass% or less relative to the total mass of the thermoplastic resin, and the polyamide resin composition contains endothermic filler (C), fibrous reinforcing material (D), and scale-like or plate-like inorganic particles (E), it is possible to sufficiently improve tracking resistance while also improving flame retardancy. [Industrial Applicability]

[0224] The polyamide resin composition of the present invention is useful, for example, for insert-molded articles (for example, automobile parts). [Explanation of symbols]

[0225] 100 Busbar Unit 110 Busbar 120 Retaining member< / mfr>

Claims

1. A polyamide resin composition for insert molding, comprising: a polyamide resin (A1) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC); a halogen-based flame retardant (B); an endothermic filler (C); Scaly or plate-like inorganic particles (E); Including, the content of the halogen-based flame retardant (B) is 21.5 mass% or more and 35.0 mass% or less, based on the total mass of the thermoplastic resin contained in the polyamide resin composition; Polyamide resin composition.

2. Further comprising a polyamide resin (A2) having a heat of fusion (ΔH) measured by a differential scanning calorimeter (DSC) of 0 J / g or more and 5 J / g or less, The polyamide resin composition according to claim 1.

3. the content of the polyamide resin (A2) is 3% by mass or more and 25% by mass or less based on the total mass of the polyamide resin (A1) and the polyamide resin (A2); The polyamide resin composition according to claim 2.

4. When the inorganic particles (E) are mica particles, the content of the halogen-based flame retardant (B) is 20% by mass or more and 25% by mass or less, based on the total mass of the thermoplastic resin; When the inorganic particles (E) are glass flakes, the content of the halogen-based flame retardant (B) is 22 mass% or more and 35 mass% or less, based on the total mass of the thermoplastic resin. The polyamide resin composition according to claim 1.

5. Further comprising a fibrous reinforcing material (D), The polyamide resin composition according to claim 1.

6. A metal member; A resin member comprising the polyamide resin composition according to any one of claims 1 to 5, which is composited with the metal member. Metal-resin composite.

Images