JP7664716B2 - Metal-resin bonded body and resin composition - Google Patents

Description

The present invention relates to a metal-resin bonded body.

Since polyamide resin compositions have been excellent in moldability, mechanical properties and chemical resistance, they have been widely used as materials for various parts in industrial materials, automobiles, electrical and electronic equipment and other industrial applications.

When using a polyamide resin composition for these applications, it is required that the resin member molded from the polyamide resin composition be firmly bonded to a metal member. In addition, when using a polyamide resin composition for in-vehicle electric/electronic devices, it is also required that the resin member be firmly bonded to a metal member whose main component is copper.

For example, Patent Document 1 describes a copper-resin composite in which a polyamide resin composition is bonded to a surface-treated copper member.

JP 2017-132243 A

However, according to the findings of the present inventors, even with the composite described in Patent Document 1, it was difficult to obtain the desired bonding strength. Furthermore, when a polyamide resin composition is used in an in-vehicle electric or electronic device, high adhesion (airtightness) is required between the resin member and the copper member to suppress leakage of oil such as automatic transmission fluid (ATF), but even with the composite described in Patent Document 1, it was difficult to obtain the desired airtightness.

In view of these circumstances, the present invention aims to provide a metal-resin bonded body in which a resin member formed from a polyamide resin composition is firmly bonded to a copper member and also has improved airtightness.

A metal-resin bonded body according to one embodiment of the present invention comprises a copper member having a roughened surface, and a resin member containing a polyamide resin (A) bonded to the roughened surface of the copper member, wherein the bond strength between the copper member and the resin member is 40 MPa or more, and is calculated by dividing the breaking load (N) measured between the copper member and the resin member using a tensile tester at room temperature (23°C) under conditions of a chuck distance of 60 mm and a tensile speed of 10 mm/min by the bonding area between the copper member and the resin member, and the amount of helium leak at the bonded portion between the copper member and the resin member is 1 x ^10-6 Pa· ^m3 /s or less, as measured by a method in accordance with ISO19095.

A metal-resin bonded body according to another embodiment of the present invention has a copper member having a roughened surface, and a resin member containing a polyamide resin (A) bonded to the roughened surface of the copper member, the resin member containing a polyamide resin (A) having a melting point (Tm) of 280°C or higher as measured by differential scanning calorimetry (DSC), and a modified polyolefin resin (C) in an amount of 0.1% by mass or more and 10% by mass or less relative to the total mass of the resin member.

The present invention provides a metal-resin bonded body in which a resin member formed from a polyamide resin composition is firmly bonded to a copper member and has improved airtightness.

1. First embodiment The first embodiment of the present invention relates to a metal-resin joined body having a copper member having a roughened surface and a polyamide resin member containing a polyamide resin (A) joined to the roughened surface of the copper member.

The copper member has a surface roughened by any method, and the surface may be roughened by a chemical treatment such as immersion in a treatment solution containing a base or acid or etching, or a physical treatment such as laser or blasting.

The surface of the roughened copper member preferably has a center-to-center distance (pitch) of 5 nm or more and 500 μm or less between the multiple convex portions formed by the roughening treatment. When the center-to-center distance between the multiple convex portions is 5 nm or more, the recesses between the convex portions are appropriately large, so that the resin composition can easily penetrate sufficiently into the recesses during bonding, and the bonding strength between the copper member and the resin member can be further improved. When the center-to-center distance between the multiple convex portions is 500 μm or less, the recesses do not become too large, so that the occurrence of gaps at the metal-resin interface of the metal-resin bonded body can be further suppressed, and the airtightness can be further improved. From the same viewpoint, it is more preferable that the center-to-center distance between the multiple convex portions is 5 μm or more and 250 μm or less. The center-to-center distance between the multiple convex portions is the average value of the distance between the center of one convex portion and the center of the adjacent convex portion.

The center-to-center distance of the multiple protrusions can be measured by removing the resin member from the metal-resin bonded body by mechanical peeling, solvent cleaning, or the like, and observing the surface of the exposed copper member using an electron microscope or laser microscope, or a surface roughness measuring device.

Specifically, when the center-to-center distance between the multiple protrusions is less than 0.5 μm, it can be observed with an electron microscope, and when the center-to-center distance between the multiple protrusions is 0.5 μm or more, it can be observed with a laser microscope or a surface roughness measuring device. For example, in a photograph of the surface of a copper member taken with an electron microscope or a laser microscope, 50 arbitrary protrusions are selected and the center-to-center distance between each of these protrusions is measured. Then, all the measured values of the center-to-center distance between the protrusions are added up and then divided by 50 (average) to determine the "center-to-center distance between the multiple protrusions."

The average ten-point mean roughness (Rz) of the roughened surface of the copper 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.

The average 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 three arbitrary straight line sections that are parallel to each other and three arbitrary straight line sections that are perpendicular to the three straight line sections, for a total of six straight line sections, and the average of these is taken as the average Rz.

The average length (RSm) of the roughness curve element of the roughened surface of the copper 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 of the multiple convex portions is less than 0.5 μm and the average length (RSm) of the roughness curve element is 0.5 μm or more and 500 μm or less. The average length of the roughness curve element can be measured according to JIS B0601 (ISO 4287) as described above.

1-2. Resin member The resin member is a resin composition in which the main component of the resin component is polyamide resin (A). The main component means that the proportion of the polyamide resin (A) in the resin component is 50% by mass or more. The proportion of the polyamide resin (A) in the resin component is preferably 60% by mass or more, and more preferably 70% by mass or more. The upper limit of the proportion of the polyamide resin (A) in the resin component is not particularly limited, but can be 100% by mass or less, may be 90% by mass or less, or may be 80% by mass or less.

1-2-1. Polyamide resin (A)
The polyamide resin may be a polyamide resin containing a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine. In this case, in order to increase the melting point (Tm) and glass transition temperature (Tg) of the polyamide resin, the component unit (Aa) derived from a dicarboxylic acid preferably contains a component unit derived from an aromatic dicarboxylic acid or an alicyclic dicarboxylic acid. The polyamide resin (A) has a role of bonding a resin member to a copper member. In addition, from the viewpoint of further increasing the bonding strength and airtightness, the polyamide resin (A) is preferably a crystalline polyamide resin.

[Component unit (Aa) derived from dicarboxylic acid]
Examples of aromatic dicarboxylic acids include terephthalic acid, naphthalenedicarboxylic acid and their esters. Examples of alicyclic dicarboxylic acids include cyclohexanedicarboxylic acid and its esters. Among them, from the viewpoint of obtaining a polyamide resin with high crystallinity and high heat resistance, the component unit (Aa) derived from dicarboxylic acid preferably includes a component unit derived from aromatic dicarboxylic acid, and more preferably includes a component unit derived from terephthalic acid.

The content of the component units derived from aromatic dicarboxylic acids or alicyclic dicarboxylic acids (preferably component units derived from aromatic dicarboxylic acids, more preferably component units derived from terephthalic acid) is not particularly limited, but is preferably 50 mol% or more and 100 mol% or less relative to the total number of moles of the component units (Aa) derived from dicarboxylic acids. If the content of the above component units is 50 mol% or more, the crystallinity of the polyamide resin is easily increased. From the same viewpoint, the content of the above component units is more preferably 70 mol% or more and 100 mol% or less.

In this embodiment, the component units (Aa) derived from dicarboxylic acids preferably include component units (a1) derived from terephthalic acid, naphthalenedicarboxylic acid, or cyclohexanedicarboxylic acid. These component units (Aa1) can enhance the crystallinity of polyamide, unlike, for example, isophthalic acid. The content of these component units (Aa1) is set to more than 20 mol% and not more than 100 mol% based on the total number of moles of component units (Aa) derived from dicarboxylic acids, from the viewpoint of ensuring the crystallinity of the polyamide resin. From the viewpoint of further enhancing the crystallinity of the polyamide resin, the content of these component units (Aa1) is preferably 45 mol% or more and 100 mol% or less based on the total number of moles of component units (Aa) derived from dicarboxylic acids, more preferably 50 mol% or more and 99 mol% or less, and even more preferably 60 mol% or more and 80 mol% or less.

The dicarboxylic acid-derived component unit (Aa) may contain an aromatic carboxylic acid component unit (Aa2) other than the above component unit (Aa1) or an aliphatic dicarboxylic acid-derived component unit (Aa3) having 4 to 20 carbon atoms, as long as the effect of the present invention is not impaired.

Examples of component units (Aa2) derived from aromatic dicarboxylic acids other than terephthalic acid include component units derived from isophthalic acid and 2-methylterephthalic acid. Of these, component units derived from isophthalic acid are preferred. When polyamide resin (A) contains component units (Aa2), the content of these component units (Aa2) is preferably 1 mol% to 50 mol% relative to the total number of moles of component units (Aa) derived from dicarboxylic acids, from the viewpoint of ensuring the crystallinity of the polyamide resin, more preferably 10 mol% to 40 mol%, even more preferably 15 mol% to 40 mol%, and particularly preferably 20 mol% to 40 mol%.

The component unit (Aa3) derived from an aliphatic dicarboxylic acid is a component unit derived from an aliphatic dicarboxylic acid having an alkylene group with 4 to 20 carbon atoms, and is preferably a component unit derived from an aliphatic dicarboxylic acid having an alkylene group with 6 to 12 carbon atoms. Examples of the aliphatic dicarboxylic acid include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid, and suberic acid component units. Among these, adipic acid and sebacic acid are preferred. When the polyamide resin (A) contains the component unit (Aa3), the content of the component unit (Aa3) is preferably 0 mol% or more and 40 mol% or less, more preferably 0 mol% or more and 20 mol% or less, even more preferably 1 mol% or more and 10 mol% or less, and particularly preferably 1 mol% or more and 5 mol% or less, based on the total number of moles of the component unit (Aa) derived from dicarboxylic acid, from the viewpoint of ensuring the crystallinity of the polyamide resin.

The polyamide resin (A) may further contain a small amount of a tribasic or higher polybasic carboxylic acid component unit such as trimellitic acid or pyromellitic acid in addition to the above-mentioned component units (Aa1), (Aa2), and (Aa3). The content of such polybasic carboxylic acid component units can be 0 mol % or more and 5 mol % or less based on the total number of moles of component units (Aa) derived from dicarboxylic acids.

[Diamine-derived component unit (Ab)]
The diamine-derived component unit (Ab) preferably contains a component unit (Ab1) derived from a linear alkylenediamine having 4 to 18 carbon atoms, and may further contain a component unit (Ab2) derived from an alkylenediamine having 4 to 18 carbon atoms and having a side chain alkyl group, or a component unit (Ab3) derived from an alicyclic diamine having 4 to 20 carbon atoms.

When the total number of moles of the diamine-derived component units contained in the polyamide resin (A) is taken as 100 mol%, the amount of the component units (Ab1) derived from linear alkylenediamines having 4 to 18 carbon atoms is preferably 20 mol% or more and 100 mol% or less, and more preferably 20 mol% or more and 80 mol% or less. When the content of the above component units is 20 mol% or more, the crystallization rate is not too slow, so that it is easy to appropriately increase the crystallinity and mechanical strength of the polyamide resin (A). When the content of the above component units is 100 mol% or less, preferably 80 mol% or less, the crystallization rate of the polyamide resin (A) is not too high, so that the fluidity during molding is not easily impaired. From the same viewpoint, it is more preferable that the content of the component units derived from linear aliphatic diamines is 30 mol% or more and 60 mol% or less of the above total.

In addition, the diamine-derived component unit (Ab) may contain a component unit (Ab2) derived from an alkylene diamine having 4 to 18 carbon atoms and a side chain alkyl group or a component unit (Ab3) derived from an alicyclic diamine having 4 to 20 carbon atoms. In this case, when the total number of moles of the diamine-derived component units contained in the polyamide resin (A) is taken as 100 mol%, it is preferable that the amount of the component unit (Ab2) derived from an alkylene diamine having 4 to 18 carbon atoms and a side chain alkyl group or the component unit (Ab3) derived from an alicyclic diamine having 4 to 20 carbon atoms is 20 mol% or more and 80 mol% or less. When the content of the above component unit is 20 mol% or more, the crystallization rate of the polyamide resin (A) tends to be moderately slow, and therefore the fluidity during molding is easily increased. When the content of the above component unit is 80 mol% or less, the crystallinity and mechanical strength of the polyamide resin (A) are not easily impaired. From the same viewpoint, it is more preferable that the content of component units derived from branched aliphatic diamines is 40 mol% or more and 70 mol% or less of the above total.

Examples of the component unit (Ab1) derived from a linear alkylenediamine having 4 to 18 carbon atoms include component units derived from 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, component units derived from 1,6-diaminohexane, 1,8-diaminooctane, 1,10-diaminodecane, and 1,12-diaminododecane are preferred, with 1,6-diaminohexane component units being more preferred. A plurality of types of these component units may be contained in the polyamide resin (A).

Examples of component units (Ab2) derived from alkylenediamines having 4 to 18 carbon atoms and having a side chain alkyl group include 1-butyl-1,2-diamino-ethane, 1,1-dimethyl-1,4-diamino-butane, 1-ethyl-1,4-diamino-butane, 1,2-dimethyl-1,4-diamino-butane, 1,3-dimethyl-1,4-diamino-butane, 1,4-dimethyl-1,4-diamino-butane, 2,3-dimethyl-1,4-diamino-butane, 2-methyl-1,5-diaminopentane, 2, 5-Dimethyl-1,6-diamino-hexane, 2,4-Dimethyl-1,6-diamino-hexane, 3,3-Dimethyl-1,6-diamino-hexane, 2,2-Dimethyl-1,6-diamino-hexane, 2,2,4-Trimethyl-1,6-diamino-hexane, 2,4,4-Trimethyl-1,6-diamino-hexane, 2,4-Diethyl-1,6-diamino-hexane, 2,3-Dimethyl-1,7-diamino-heptane, 2,4-Dimethyl-1,7-diamino-heptane, 2,5-Dimethyl 1,7-diamino-heptane, 2,2-dimethyl-1,7-diamino-heptane, 2-methyl-4-ethyl-1,7-diamino-heptane, 2-ethyl-4-methyl-1,7-diamino-heptane, 2,2,5,5-tetramethyl-1,7-diamino-heptane, 3-isopropyl-1,7-diamino-heptane, 3-isooctyl-1,7-diamino-heptane, 1,3-dimethyl-1,8-diamino-octane, 1,4-dimethyl-1,8-diamino-octane, 2,4-dimethyl-1,8-diamino-octane, The component units include those derived from ethyl-1,8-diamino-octane, 3,4-dimethyl-1,8-diamino-octane, 4,5-dimethyl-1,8-diamino-octane, 2,2-dimethyl-1,8-diamino-octane, 3,3-dimethyl-1,8-diamino-octane, 4,4-dimethyl-1,8-diamino-octane, 3,3,5-trimethyl-1,8-diamino-octane, 2,4-diethyl-1,8-diamino-octane, and 5-methyl-1,9-diamino-nonane. Among these, the component units derived from side chain alkyl diamines having 1 to 2 side chain alkyl groups with 1 to 2 carbon atoms and 4 to 10 carbon atoms in the main chain are preferred, and 2-methyl-1,5-diaminopentane component units are more preferred. A plurality of types of these component units may be contained in the polyamide resin (A).

Examples of component units (Ab3) derived from alicyclic diamines having 4 to 20 carbon atoms include 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, isophoronediamine, piperazine, 2,5-dimethylpiperazine, bis(4-aminocyclohexyl)methane, bis(4-aminocyclohexyl)propane, 4,4'-diamino-3,3'-dimethyldicyclohexylpropane, 4,4'-diamino-3,3'-dimethyldicyclohexylmethan, These include component units derived from 4,4'-diamino-3,3'-dimethyl-5,5'-dimethyldicyclohexylmethane, 4,4'-diamino-3,3'-dimethyl-5,5'-dimethyldicyclohexylpropane, α,α'-bis(4-aminocyclohexyl)-p-diisopropylbenzene, α,α'-bis(4-aminocyclohexyl)-m-diisopropylbenzene, α,α'-bis(4-aminocyclohexyl)-1,4-cyclohexane, and α,α'-bis(4-aminocyclohexyl)-1,3-cyclohexane. Among these, component units derived from 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(aminomethyl)cyclohexane, bis(4-aminocyclohexyl)methane, and 4,4'-diamino-3,3'-dimethyldicyclohexylmethane are preferred, and component units derived from 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 1,3-bis(aminocyclohexyl)methane, and 1,3-bis(aminomethyl)cyclohexane are more preferred.

In this specification, the number of carbon atoms in a component unit derived from an alkylenediamine having a side chain alkyl group is the sum of the number of carbon atoms in the main chain alkylene group and the number of carbon atoms in the side chain alkyl group, unless otherwise specified.

The polyamide resin (A) may contain component units derived from other diamines, such as component units derived from metaxylylenediamine, in addition to the component units (Ab1) derived from linear alkylenediamines having 4 to 18 carbon atoms, component units (Ab2) derived from alkylenediamines having 4 to 18 carbon atoms and having a side chain alkyl group, and component units (Ab3) derived from alicyclic diamines having 4 to 20 carbon atoms. The content of such component units derived from other diamines may be 50 mol % or less, and preferably 40 mol % or less, based on the total amount of component units (Ab) derived from diamines.

In order to improve the thermal stability during compounding or molding and to further increase the mechanical strength, at least some of the molecular end groups of the polyamide resin (A) may be capped with a terminal capping agent. For example, when the molecular end is a carboxyl group, the terminal capping agent is preferably a monoamine, and when the molecular end is an amino group, the terminal capping agent is preferably a monocarboxylic acid.

Examples of monoamines include aliphatic monoamines such as methylamine, ethylamine, propylamine, and butylamine, alicyclic monoamines such as cyclohexylamine and dicyclohexylamine, and aromatic monoamines such as aniline and toluidine. Examples of monocarboxylic acids include aliphatic monocarboxylic acids having 2 to 30 carbon atoms such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, oleic acid, and linoleic acid, aromatic monocarboxylic acids such as benzoic acid, toluic acid, naphthalene carboxylic acid, methylnaphthalene carboxylic acid, and phenyl acetic acid, and alicyclic monocarboxylic acids such as cyclohexane carboxylic acid. Aromatic monocarboxylic acids and alicyclic monocarboxylic acids may have a substituent on the ring structure portion.

[Physical Properties]
The polyamide resin (A) can have a melting point (Tm) of 280°C or more and 340°C or less. When the melting point (Tm) of the polyamide resin (A) is 280°C or more, the mechanical strength and heat resistance of the resin composition and the molded body in the high temperature range are not easily impaired, and when it is 340°C or less, the molding temperature does not need to be excessively high, so that the molding processability of the resin composition is likely to be good. From the above viewpoint, the melting point (Tm) of the polyamide resin is more preferably 290°C or more and 340°C or less, and even more preferably 300°C or more and 340°C or less.

The polyamide resin (A) may have a glass transition temperature (Tg) of 80°C or higher and 150°C or lower.

The heat of fusion (ΔH) of the polyamide resin (A) is preferably 20 J/g or more. When the heat of fusion (ΔH) of the polyamide resin (A) is 20 J/g or more, the resin member has crystallinity and therefore the heat resistance of the resin member is easily improved. The upper limit of the heat of fusion (ΔH) of the polyamide resin (A) is not particularly limited, but may be 130 J/g from the viewpoint of not impairing the moldability. The heat of fusion (ΔH) of the polyamide resin (A) is preferably 30 J/g or more and 130 J/g or less, and more preferably 30 J/g or more and 100 J/g or less.

The heat of fusion (ΔH), melting point (Tm) and glass transition temperature (Tg) of polyamide resin can be measured using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.).

Specifically, about 5 mg of crystalline polyamide resin is sealed in a measuring aluminum pan and heated from room temperature to 350°C at 10°C/min. In order 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 in this second heating is the melting point (Tm) of the crystalline polyamide resin, and the transition point corresponding to the glass transition is the glass transition temperature (Tg). The heat of fusion (ΔH) is determined from the area of the endothermic peak during melting in the first heating process in accordance with JIS K7122.

The melting point (Tm), glass transition temperature (Tg) and heat of fusion (ΔH) of polyamide resin (A) can be adjusted, for example, by the composition of the component unit (Aa1) derived from the dicarboxylic acid described above, or the number of carbon atoms per component unit (Ab1) derived from the diamine. In order to increase the melting point of polyamide resin (A), for example, the content ratio of the component unit derived from terephthalic acid may be increased.

The intrinsic viscosity [η] of the polyamide resin (A) measured in 96.5% sulfuric acid at a temperature of 25°C is preferably 0.6 dl/g or more and 1.5 dl/g or less. When the intrinsic viscosity [η] of the polyamide resin (A) is 0.6 dl/g or more, the mechanical strength (toughness, etc.) of the molded body is easily increased, and when it is 1.5 dl/g or less, the fluidity of the resin composition during molding is not easily impaired. From the same viewpoint, the intrinsic viscosity [η] of the polyamide resin (A) is more preferably 0.8 dl/g or more and 1.2 dl/g or less. The intrinsic viscosity [η] can be adjusted by the amount of terminal blocking of the polyamide resin (A), etc.

The intrinsic viscosity of polyamide resin (A) can be measured in accordance with JIS K6810 (1977). Specifically, 0.5 g of polyamide resin (A) is dissolved in 50 ml of 96.5% sulfuric acid solution to prepare a sample solution. The flow time of this sample solution is measured under conditions of 25±0.05° C. using an Ubbelohde viscometer, and the obtained value can be applied to the following formula to calculate the intrinsic viscosity.
[η]=ηSP/[C(1+0.205ηSP)]

In the above formula, each algebra or variable represents the following:
[η]: Intrinsic viscosity (dl/g)
ηSP: specific viscosity C: sample concentration (g/dl)

ηSP is calculated by the following formula:
ηSP=(t-t0)/t0
t: number of seconds for sample solution to flow (seconds)
t0: Number of seconds (seconds) for blank sulfuric acid to flow

[Production method]
The polyamide resin can be produced, for example, by polycondensing the above-mentioned dicarboxylic acid and the above-mentioned diamine in a homogeneous solution. Specifically, the dicarboxylic acid and the diamine are heated in the presence of a catalyst as described in WO 03/085029 to obtain a low-order condensate, and then the melt of the low-order condensate is subjected to shear stress to polycondense the low-order condensate.

The aforementioned end-capping agent may be added to the reaction system in order to adjust the intrinsic viscosity of the polyamide resin. The intrinsic viscosity [η] (or molecular weight) of the polyamide resin can be adjusted by the amount of end-capping agent added.

The end-capping agent is added to the reaction system of the dicarboxylic acid and the diamine. The amount added is preferably 0.07 moles or less, and more preferably 0.05 moles or less, per mole of the total amount of dicarboxylic acid.

The content of polyamide resin (A) is preferably 35% by mass or more and 80% by mass or less, more preferably 40% by mass or more and 80% by mass or less, and even more preferably 50% by mass or more and 80% by mass or less, based on the total mass of the resin composition constituting the resin member. The higher the content of polyamide resin (A), the higher the bonding strength of the resin member to the copper member can be. On the other hand, the upper limit of polyamide resin (A) can be set within the above range in order to leave room for further improving the bonding strength and improving the airtightness by slowing down the crystallization rate by adding other components.

1-2-2. Polyamide resin (B)
In addition to the polyamide resin (A), the resin member preferably contains a polyamide resin (B) whose heat of fusion (ΔH) measured by a differential scanning calorimeter (DSC) is lower than that of the polyamide resin (A). In addition, it is preferable that the melting point (Tm) of the polyamide resin (B) is not substantially measured by differential scanning calorimetry (DSC). Since the crystallinity of the polyamide resin (B) is lower than that of the polyamide resin (A), the crystallization rate of the resin composition during molding of the resin member can be delayed. This allows the resin composition constituting the resin member to flow sufficiently along the unevenness of the surface of the roughened copper member, and the resin composition can be sufficiently adhered to the unevenness. Therefore, it is considered that the polyamide resin (B) can further increase the bonding strength between the copper member and the resin member and further increase the airtightness.

"The melting point (Tm) is not substantially measured" means that the transition point corresponding to the glass transition is not substantially observed in the measurement method described above.

That is, the heat of fusion (ΔH) of polyamide resin (B) is preferably 5 J/g or less, and more preferably 0 J/g. When the heat of fusion (ΔH) of polyamide resin (B) is 5 J/g or less, the crystallinity is appropriately low, so that the crystallization rate of the resin composition during molding of the resin member can be more sufficiently delayed. It is preferable that polyamide resin (B) exhibits amorphousness. The heat of fusion (ΔH) can be measured by the same method as described above.

The polyamide resin (B) may be a polyamide resin containing a component unit (Ba) derived from a dicarboxylic acid and a component unit (b) derived from a diamine.

[Component unit (Ba) derived from dicarboxylic acid]
The component units (Ba) derived from a dicarboxylic acid preferably contain at least a component unit derived from isophthalic acid. The component units derived from isophthalic acid can reduce the crystallinity of the polyamide resin (B).

The content of the component units derived from isophthalic acid is preferably 40 mol% or more, more preferably 50 mol% or more, based on the total amount of the component units (Ba) derived from dicarboxylic acids. If the content of the component units derived from isophthalic acid is 40 mol% or more, it is easy to make the polyamide resin (B) amorphous. Although there is no particular limit to the upper limit of the content of the component units derived from isophthalic acid, it can be 100 mol% or less, and preferably 90 mol% or less.

The component unit (Ba) derived from a dicarboxylic acid may further contain component units derived from other dicarboxylic acids other than the component units derived from isophthalic acid, within a range that does not impair the effects of the present invention. 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 aliphatic dicarboxylic acids and alicyclic dicarboxylic acids described above, respectively. Among them, aromatic dicarboxylic acids other than isophthalic acid are preferred, and terephthalic acid is more preferred.

In the dicarboxylic acid-derived component units (Ba), the molar ratio of the component units derived from isophthalic acid to the component units derived from an aromatic dicarboxylic acid other than isophthalic acid (preferably terephthalic acid) is preferably isophthalic acid-derived component units/aromatic dicarboxylic acid other than isophthalic acid (preferably terephthalic acid)=55/45 to 100/0 (molar ratio), and more preferably 60/40 to 90/10 (molar ratio). When the amount of the component units derived from isophthalic acid is equal to or greater than a certain level, the polyamide resin (B) tends to become amorphous, which retards the crystallization rate of the resin composition during molding of the resin member, thereby further increasing the bonding strength between the copper member and the resin member and further increasing the airtightness.

[Diamine-derived component unit (Bb)]
The diamine-derived component unit (Bb) preferably includes a component unit derived from an aliphatic diamine having 4 to 15 carbon atoms.

The aliphatic diamine having 4 to 15 carbon atoms is the same as the aliphatic diamine having 4 to 15 carbon atoms described above, and is preferably 1,6-hexanediamine.

The content of component units derived from aliphatic diamines having 4 to 15 carbon atoms is preferably 50 mol% or more, and more preferably 60 mol% or more, based on the total amount of component units (Bb) derived from diamines.

The diamine-derived component unit (Bb) may further contain component units derived from other diamines other than the component units derived from the aliphatic diamine having 4 to 15 carbon atoms, within a range that does not impair the effects of the present invention. Examples of the other diamines include alicyclic diamines and aromatic diamines. The alicyclic diamines and aromatic diamines may be the same as the above-mentioned alicyclic diamines and aromatic diamines, respectively. The content of the other diamine component units may be 50 mol% or less, and preferably 40 mol% or less.

Specific examples of polyamide resin (B) include polycondensates of isophthalic acid/terephthalic acid/1,6-hexanediamine/bis(3-methyl-4-aminocyclohexyl)methane, polycondensates of isophthalic acid/bis(3-methyl-4-aminocyclohexyl)methane/ω-laurolactam, polycondensates of isophthalic acid/terephthalic acid/1,6-hexanediamine, and isophthalic acid/2,2,4-trimethyl-1,6-hexanediamine. Polycondensates of isophthalic acid/terephthalic acid/2,2,4-trimethyl-1,6-hexanediamine/2,4,4-trimethyl-1,6-hexanediamine, polycondensates of isophthalic acid/bis(3-methyl-4-aminocyclohexyl)methane/ω-laurolactam, and polycondensates of isophthalic acid/terephthalic acid/other diamine components are included. Among these, polycondensates of isophthalic acid/terephthalic acid/1,6-hexanediamine are preferred. Only one type of polyamide resin (B) may be included, or two or more types may be included.

The intrinsic viscosity [η] of polyamide resin (B) measured at 25°C in 96.5% sulfuric acid is preferably 0.6 to 1.6 dl/g, more preferably 0.65 to 1.2 dl/g. The intrinsic viscosity [η] of polyamide resin (B) can be measured in the same manner as the intrinsic viscosity [η] of polyamide resin (A) described above.

Polyamide resin (B) can be produced in the same manner as polyamide resin (A) described above.

The proportion of polyamide resin (B) in the resin components is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more. By setting the proportion of polyamide resin (B) in the above range, the effect of improving the bonding strength and airtightness due to the delay in crystallization can be more fully achieved. The upper limit of the proportion of polyamide resin (B) in the resin components is not particularly limited, but from the viewpoint of blending a sufficient amount of polyamide resin (A) in the resin composition, it can be 30% by mass or less, and may be 25% by mass or less.

1-2-3. Modified polyolefin resin (C)
The resin member may contain a modified polyolefin resin (C) in addition to the polyamide resin (A). The modified polyolefin resin (C) can delay the crystallization rate of the resin composition during molding of the resin member. This allows the resin composition constituting the resin member to flow sufficiently along the unevenness of the surface of the roughened copper member, and the resin composition can be sufficiently adhered to the unevenness. Therefore, it is considered that the modified polyolefin resin (C) can further increase the bonding strength between the copper member and the resin member and further increase the airtightness.

The modified polyolefin resin (C) is an olefin polymer having a polyolefin unit and a functional group structural unit. Examples of the functional group of the functional group structural unit include a functional group containing a heteroatom and an aromatic hydrocarbon group. Preferably, the modified polyolefin resin (C) is a modified olefin polymer having a polyolefin unit and a structural unit (functional group structural unit) containing a functional group containing a heteroatom.

The heteroatom is preferably oxygen. Examples of functional groups containing a heteroatom include ester groups, ether groups, carboxylic acid groups (including carboxylic anhydride groups), aldehyde groups, and ketone groups.

The modified polyolefin resin (C) contains 0.1 to 5.0% by mass of functional group structural units relative to 100% by mass of the modified polyolefin resin (C). The content of the functional group structural units contained in the modified polyolefin resin (C) is preferably 0.2 to 3.0% by mass, preferably 0.2 to 2.0% by mass, and more preferably 0.2 to 1.2% by mass. When the amount of functional group structural units is within the above range, the impact resistance and elongation of the resin composition tend to be increased.

The content of the functional group structural unit contained in the modified polyolefin resin (C) is determined by a known means such as the charge ratio when the olefin polymer and the functional group-containing organic compound are reacted in the presence of a radical initiator, etc., or by ¹³ C NMR measurement or ¹ H NMR measurement. Specific NMR measurement conditions include the following conditions.

^{The 1} H NMR measurement can be performed using a nuclear magnetic resonance apparatus of ECX400 manufactured by JEOL Ltd., with the solvent being deuterated orthodichlorobenzene, the sample concentration being 20 mg/0.6 mL, the measurement temperature being 120° C., the observation nucleus being ¹ H (400 MHz), the sequence being a single pulse, the pulse width being 5.12 μsec (45° pulse), the repetition time being 7.0 sec, and the number of accumulations being 500 or more. The reference chemical shift is set to 0 ppm for hydrogen of tetramethylsilane, but similar results can be obtained by setting the peak derived from the residual hydrogen of deuterated orthodichlorobenzene at 7.10 ppm as the reference value of the chemical shift. Peaks such as ¹ H derived from functional group-containing compounds are assigned by the usual method.

The ¹³ C NMR measurement can be performed using a nuclear magnetic resonance apparatus of the ECP500 type manufactured by JEOL Ltd., using a mixed solvent of orthodichlorobenzene/heavy benzene (80/20% by volume) as the solvent, a measurement temperature of 120° C., an observation nucleus of ¹³ C (125 MHz), single pulse proton decoupling, 45° pulse, a repetition time of 5.5 seconds, an accumulation number of 10,000 times or more, and a chemical shift reference value of 27.50 ppm. Assignment of various signals is performed based on a conventional method, and quantification can be performed based on the accumulated value of the signal intensity.

On the other hand, the backbone portion of the modified polyolefin resin (C) is preferably a structure derived from a polyolefin, and is preferably a known olefin polymer such as an ethylene-based polymer, a propylene-based polymer, a butene-based polymer, or a copolymer of these olefins. It is more preferable that the backbone portion of the olefin polymer is a copolymer of ethylene and an α-olefin having 3 or more carbon atoms (hereinafter also simply referred to as an "ethylene-α-olefin copolymer").

Examples of the α-olefins having 3 or more carbon atoms include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene. Specific examples of the ethylene-α-olefin copolymers include ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-1-hexene copolymers, ethylene-1-octene copolymers, and ethylene-4-methyl-1-pentene copolymers. Of these, ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-4-methyl-1-pentene copolymers, ethylene-1-hexene copolymers, and ethylene-1-octene copolymers are preferred.

When the total number of moles of structural units contained in the ethylene-α-olefin copolymer is taken as 100 mol %, the ethylene-derived structural units are preferably contained in an amount of 70 to 99.5 mol %, and more preferably in an amount of 80 to 99 mol %. Furthermore, when the total number of moles of structural units contained in the ethylene-α-olefin copolymer is taken as 100 mol %, the ethylene-α-olefin copolymer is preferably contained in an amount of 0.5 to 30 mol %, and more preferably in an amount of 1 to 20 mol %, of structural units derived from α-olefins.

The melt flow rate (MFR) of the ethylene-α-olefin copolymer at 190°C under a load of 2.16 kg according to ASTM D1238 is preferably 0.01 to 20 g/10 min, more preferably 0.05 to 20 g/10 min, and even more preferably 0.1 to 10 g/10 min.

The modified polyolefin resin (C) can be obtained, for example, by reacting the above-mentioned olefin polymer with a compound having the above-mentioned functional group in a specific ratio.

Preferred examples of functional group-containing compounds to be reacted with the olefin polymer include unsaturated carboxylic acids or derivatives thereof. Specific examples of the functional group-containing compounds include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, endo-cis-bicyclo[2,2,1]hept-5-ene-2,3-dicarboxylic acid (Nadic acid [trademark]), and derivatives thereof such as acid halides, amides, imides, acid anhydrides, and esters. Among these, unsaturated dicarboxylic acids or their acid anhydrides are preferred, and maleic acid, Nadic acid [trademark], or their acid anhydrides are particularly preferred.

The functional group-containing compound is preferably maleic anhydride. Maleic anhydride has a relatively high reactivity with the above-mentioned olefin polymer, and is itself less susceptible to major structural changes due to polymerization, etc., and tends to have a stable basic structure. For this reason, it has various advantages, such as being able to obtain a modified polyolefin resin (C) of stable quality.

Examples of methods for obtaining modified polyolefin resin (C) using ethylene/α-olefin copolymers include a method of so-called graft modification of the ethylene/α-olefin copolymer with a functional group-containing compound corresponding to the functional group structural unit.

The density of the modified polyolefin resin (C) is preferably 0.80 to 0.96 g/cm ³ , more preferably 0.85 to 0.95 g/cm ³ , and even more preferably 0.89 to 0.94 g/cm ³ .

Furthermore, the intrinsic viscosity [η] of the modified polyolefin resin (C) measured in a 135°C decalin (decahydronaphthalene) solution is preferably 1.5 to 4.5 dl/g, more preferably 1.6 to 3 dl/g. If [η] is within the above range, the resin composition can achieve both high levels of mechanical strength and injection flowability.

The [η] of modified polyolefin resin (C) in decalin at 135°C is measured in the usual manner as follows. 20 mg of sample is dissolved in 15 ml of decalin, and the specific viscosity (ηsp) is measured in an atmosphere of 135°C using an Ubbelohde viscometer. 5 ml of decalin is further added to this decalin solution to dilute it, and the same specific viscosity measurement is then performed. This dilution operation and viscosity measurement are repeated two more times, and the "ηsp/C" value when the concentration (C) is extrapolated to zero is taken as the limiting viscosity [η].

The melt flow rate (MFR, conforming to JIS K7210, temperature 190°C, load 21.2 N) of the modified polyolefin resin (C) of the present invention is preferably 0.01 to 20 g/10 min, more preferably 0.05 to 20 g/10 min, and even more preferably 0.1 to 10 g/10 min. If the MFR is less than 0.01 g/10 min, the fluidity is poor, and if it exceeds 20 g/10 min, the impact strength may be reduced depending on the shape of the molded product.

The proportion of modified polyolefin resin (C) in the resin components is preferably 0.1% by mass or more, more preferably 0.8% by mass or more, and even more preferably 1.0% by mass or more. By setting the proportion of polyamide resin (B) in the above range, the effect of improving bonding strength and airtightness due to delayed crystallization can be more fully achieved. The upper limit of the proportion of polyamide resin (B) in the resin components is not particularly limited, but from the viewpoint of blending a sufficient amount of polyamide resin (A) in the resin composition, it can be 10% by mass or less, preferably 5% by mass or less, and more preferably 4% by mass or less.

1-2-4. Heat resistance stabilizer (D)
The resin member may contain a copper-based heat resistance stabilizer (D) in addition to the polyamide resin (A). The copper-based heat resistance stabilizer (D) can improve the fluidity of the resin composition when molding the resin member. This allows the resin composition constituting the resin member to flow sufficiently along the unevenness of the surface of the roughened copper member, so that the resin composition can be sufficiently adhered to the unevenness. Therefore, it is considered that the copper-based heat resistance stabilizer (D) can further increase the bonding strength between the copper member and the resin member and further increase the airtightness. In addition, the copper-based heat resistance stabilizer (D) improves the heat aging resistance of the resin composition. This is considered to be able to suppress the decrease in airtightness when the metal-resin bonded body is used under conditions in which heating or cooling is repeatedly performed.

The copper-based heat stabilizer (D) contains (i) a salt of a halogen and a metal element of Group 1 or 2 of the Periodic Table (halogen metal salt) and (ii) a copper compound, and may further contain (iii) a metal salt of a higher fatty acid as required.

(i) Examples of halogen metal salts include potassium iodide, potassium bromide, potassium chloride, sodium iodide, and sodium chloride. Of these, potassium iodide and potassium bromide are preferred. Only one type of halogen metal salt may be included, or two or more types may be included.

(ii) Examples of copper compounds include copper halides, copper salts (such as sulfate, acetate, propionate, benzoate, adipate, terephthalate, salicylate, nicotinate, and stearate), and copper chelate compounds (compounds of copper and ethylenediamine or ethylenediaminetetraacetic acid, etc.). Among these, copper iodide, cuprous bromide, cupric bromide, cuprous chloride, and copper acetate are preferred. Only one type of copper compound may be included, or two or more types may be included.

The mass ratio of (i) the halogen metal salt and (ii) the copper compound can be adjusted so that the molar ratio of halogen to copper is 0.1/1 to 200/1, preferably 0.5/1 to 100/1, and more preferably 2/1 to 40/1, from the viewpoint of making it easier to improve the heat resistance of the molded body and the corrosiveness during production.

(iii) Examples of metal salts of higher fatty acids include metal salts of higher saturated fatty acids and metal salts of higher unsaturated fatty acids.

The higher saturated fatty acid metal salt is preferably a metal salt of a saturated fatty acid having 6 to 22 carbon atoms and a metal element (M1) such as an element in Groups 1, 2, or 3 of the Periodic Table, zinc, or aluminum. Such a higher saturated fatty acid metal salt is represented by the following formula (1).
CH ₃ (CH ₂ ) _n COO (M1). ．． ．． (1)
(In formula (1), the metal element (M1) is an element of Groups 1, 2, or 3 of the Periodic Table of the Elements, zinc, or aluminum, and n can be 8 to 30.)

Examples of metal salts of higher saturated fatty acids include the lithium, sodium, magnesium, calcium, zinc and aluminum salts of capric acid, uracil acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melissic acid and lacteric acid.

The metal salt of a higher unsaturated fatty acid is preferably a metal salt of an unsaturated fatty acid having 6 to 22 carbon atoms and a metal element (M1) such as an element of Groups 1, 2, or 3 of the Periodic Table, zinc, or aluminum.

Examples of metal salts of higher unsaturated fatty acids include the lithium, sodium, magnesium, calcium, zinc and aluminum salts of undecylenic acid, oleic acid, elaidic acid, cetoleic acid, erucic acid, brassidic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, stearic acid, 2-hexadecenoic acid, 7-hexadecenoic acid, 9-hexadecenoic acid, gadoleic acid, gadoelaidic acid and 11-eicosenoic acid.

Examples of copper-based heat stabilizers (D) include a mixture of 10% by mass of copper (I) iodide and 90% by mass of potassium iodide, and a mixture of 14.3% by mass of copper (I) iodide and 85.7% by mass of potassium iodide/calcium distearate (98:2 by mass ratio).

The content of the copper-based heat resistance stabilizer (D) in the resin composition constituting the resin member can be 0.01% by mass or more and 3% by mass or less, preferably 0.1% by mass or more and 3% by mass or less, and more preferably 0.1% by mass or more and 0.5% by mass or less, based on the total mass of the resin composition. When the amount of the copper-based heat resistance stabilizer (D) is 0.01% by mass or more based on the total mass of the resin composition, the bonding strength and airtightness can be more sufficiently increased, and the decrease in airtightness when the metal-resin bonded body is used under conditions in which heating or cooling is performed repeatedly can be more sufficiently suppressed. Furthermore, when it is 3% by mass or less, the mechanical strength of the resin member is less likely to be impaired.

1-2-5. Other Components The resin member may contain other known components.

Examples of other components include reinforcing materials, crystal nucleating agents, flow improvers, colorants, corrosion resistance improvers, drip prevention agents, ion trapping agents, elastomers (rubbers), antistatic agents, release agents, antioxidants (phenols, amines, sulfurs, phosphorus, etc.), heat stabilizers other than those mentioned above (lactone compounds, vitamin E, hydroquinones, etc.), light stabilizers (benzotriazoles, triazines, benzophenones, benzoates, hindered amines, oxanilides, etc.), other polymers (polyolefins, olefin copolymers such as ethylene-propylene copolymers, ethylene-1-butene copolymers, olefin copolymers such as propylene-1-butene copolymers, polystyrene, polyamides, polycarbonates, polyacetals, polysulfones, polyphenylene oxides, fluororesins, silicone resins, LCPs, etc.). Among these, it is preferable that the resin composition constituting the resin member further contains a reinforcing material from the viewpoint of increasing the mechanical strength of the molded body.

The reinforcing material can impart high mechanical strength to the resin composition. Examples of reinforcing materials include fibrous reinforcing materials such as glass fiber, wollastonite, potassium titanate whiskers, calcium carbonate whiskers, aluminum borate whiskers, magnesium sulfate whiskers, zinc oxide whiskers, milled fiber, and cut fiber, as well as granular reinforcing materials. Of these, one type may be used alone, or two or more types may be used in combination. Among these, wollastonite, glass fiber, and potassium titanate whiskers are preferred because they are easy to increase the mechanical strength of the molded body, and wollastonite or glass fiber is more preferred.

From the viewpoint of moldability of the resin composition and the mechanical strength and heat resistance of the resulting molded body, the average fiber length of the fibrous reinforcing material may be, for example, 1 μm or more and 20 mm or less, preferably 5 μm or more and 10 mm or less. The aspect ratio of the fibrous reinforcing material may be, for example, 5 or more and 2000 or less, preferably 30 or more and 600 or less.

The average fiber length and average fiber diameter of the fibrous reinforcing material can be measured by the following method.
1) The resin composition is dissolved in a hexafluoroisopropanol/chloroform solution (0.1/0.9% by volume), and then filtered to obtain a filtrate.
2) The filtrate 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 designated as qi, and the weight average length (Lw) is calculated based on 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 having 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)

The amount of fibrous reinforcing material contained is not particularly limited, but can be, for example, 15% by mass or more and 70% by mass or less relative to the total mass of the resin composition.

The crystal nucleating agent can increase the crystallinity of the molded body. Examples of crystal nucleating agents include metal salt-based compounds including sodium 2,2-methylenebis(4,6-di-t-butylphenyl)phosphate, aluminum tris(p-t-butylbenzoate), and stearates, sorbitol-based compounds including bis(p-methylbenzylidene)sorbitol and bis(4-ethylbenzylidene)sorbitol, and inorganic substances including talc, calcium carbonate, and hydrotalcite. Of these, talc is preferred from the viewpoint of further increasing the crystallinity of the molded body. These crystal nucleating agents may be used alone or in combination of two or more.

The content of the crystal nucleating agent is preferably 0.1 parts by mass or more and 5 parts by mass or less, and more preferably 0.1 parts by mass or more and 3 parts by mass or less, based on the total mass of the resin composition. When the content of the crystal nucleating agent is within the above range, it is easy to sufficiently increase the crystallinity of the molded body and to obtain sufficient mechanical strength.

The flow improver enhances the injection flowability of the resin composition and improves the appearance of the resulting molded article. The flow improver 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.

The oxycarboxylic acid constituting the oxycarboxylic acid metal salt may be an aliphatic oxycarboxylic acid or an aromatic oxycarboxylic acid. Examples of the aliphatic oxycarboxylic acid include aliphatic oxycarboxylic 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 oxycarboxylic acid include salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, gallic acid, mandelic acid, and trovaic acid.

Examples of metals constituting the above metal oxycarboxylates include alkali metals such as lithium, and alkaline earth metals such as magnesium, calcium, and barium.

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

Examples of higher fatty acids that make up the above 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.

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

Of these, the higher fatty acid metal salts are preferably calcium stearate, magnesium stearate, barium stearate, calcium behenate, sodium montanate, calcium montanate, etc.

The content of the flow improver is preferably 0.01% by mass or more and 1.3% by mass or less, based on the total mass of the resin composition. If the content of the flow improver is 0.01% by mass or more, the flowability during molding is likely to be increased, and the appearance of the resulting molded product is likely to be improved. If the content of the flow improver is 1.3% by mass or less, gas due to decomposition of the flow improver is unlikely to be generated during molding, and the product's appearance is likely to be good.

The colorant imparts a desired color tone to the molded body. The colorant is not particularly limited, but may be a pigment. Examples of pigments 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.

The colorant content is preferably 0.01% by mass or more and 5% by mass or less, and more preferably 0.1% by mass or more and 2% by mass or less, based on the total mass of the resin composition.

The resin composition can be produced by a known resin kneading method, for example, by mixing the polyamide resin and, if necessary, other components with a Henschel mixer, V blender, ribbon blender, or tumbler blender, or by mixing and then melt-kneading the mixture with a single-screw extruder, a multi-screw extruder, a kneader, or a Banbury mixer, followed by granulation or pulverization.

1-3. Manufacturing method of metal resin bonded body The manufacturing method of the metal resin composite structure is not particularly limited, but may include, for example, (1) a step of preparing a copper member having a roughened surface, and (2) a step of injecting a molten resin composition onto the roughened surface of the copper member, solidifying it, and bonding the resin member.

1-3-1. Preparation of Surface-Roughened Copper Member First, a copper member having an uneven structure on at least a portion of its surface is prepared.

The method of obtaining the copper member having a fine uneven structure is not particularly limited.For example, the method of using laser processing, the method of immersing the copper member in an inorganic base aqueous solution such as NaOH or an inorganic acid aqueous solution such as HCl or _HNO3 , the method of treating the copper member by anodization, the substitution crystallization method of etching with an acid-based etching agent (preferably an acid-based etching agent aqueous solution containing inorganic acid, ferric ion, cupric ion, and if necessary, manganese ion, aluminum chloride hexahydrate, sodium chloride, etc.), the method of immersing the copper member in an aqueous solution such as hydrazine hydrate, ammonia, and water-soluble amine compound, and the like, and the hot water treatment method can be used.

1-3-2. Joining of Resin Members The copper member having the roughened surface prepared above is placed in a cavity (space) in an injection molding die.

Then, the resin composition is injected into the cavity of the mold so that at least a portion of the resin composition is in contact with the roughened surface of the copper member. The resin composition is then cooled and solidified to bond the copper member and the resin member.

The temperature of the injection molding die is not particularly limited as long as it is a temperature at which the resin composition can be melted to a state suitable for injection molding, but it can be, for example, 100 to 350°C.

After injection and pressure holding, the mold is cooled, then opened and, if necessary, ejected using an ejector pin to obtain a metal-resin bonded body.

As the mold, a known injection molding mold, such as a mold for high speed heat cycle molding (RHCM, heat & cool molding) or a core-back mold for foam molding can be used.

2. Second embodiment The second embodiment of the present invention relates to a metal-resin joined body having a copper member having a roughened surface and a resin member containing a polyamide resin joined to the roughened surface of the copper member, and having the following characteristics.

The copper member and resin member of the first embodiment described above can be used to realize a metal-resin bonded body having the following characteristics. However, the metal-resin bonded body of this embodiment is not limited to the metal-resin bonded body of the first embodiment, and the composition of the resin composition and the types and amounts of various additives are not limited to the resin member of the first embodiment as long as the following characteristics can be realized.

The above metal-resin bonded body has a bond strength of 40 MPa or more, which is obtained by dividing the breaking load (N) measured between the copper member and the resin member using a tensile tester at room temperature (23°C) under conditions of a chuck distance of 60 mm and a tensile speed of 10 mm/min by the bonded area between the copper member and the resin member. The bond strength is preferably 45 MPa or more, more preferably 50 MPa or more, even more preferably 55 MPa or more, and particularly preferably 60 MPa or more. A metal-resin bonded body having the above characteristics has a high bond strength between the copper member and the resin member.

Furthermore, the metal-resin bonded body has a helium leakage amount of 1×10 ⁻⁶ Pa·m ³ /s or less at a bonded portion between the copper member and the resin member, as measured by a method conforming to ISO 19095. The leakage amount is preferably 9×10 ⁻⁷ Pa·m ³ /s or less, and more preferably 8×10 ⁻⁷ Pa·m ³ /s or less. The metal-resin bonded body having the above characteristics has high adhesion (airtightness) between the copper member and the resin member, and is less susceptible to leakage of gas or liquid (oil, water, etc.).

In addition, in the metal-resin bonded body, after a thermal shock test under the following conditions is performed, the amount of helium leakage at the bonded portion between the copper member and the resin member, measured by a method conforming to ISO 19095, is less than twice the amount of helium leakage before the thermal shock test is performed. The amount of leakage is preferably less than 1.5 times, and more preferably less than 1.2 times.
(Conditions for thermal shock testing)
Temperature range: -40℃ to 150℃
Cycle conditions: -40°C, 150°C, 30 minutes each, 1 round trip, 1 cycle Number of cycles: 500

In addition, when the resin member of the metal-resin bonded body is processed into a test piece of 100 mm x 100 mm x 3 mm, the tracking resistance of the test piece evaluated in accordance with IEC 60112 is preferably greater than 200 V, more preferably greater than 400 V, and even more preferably greater than 600 V.

3. Uses of Resin Composition The resin composition of the present invention can be molded by a known molding method such as compression molding, injection molding, or extrusion molding to be used as various molded articles.

Furthermore, the above-mentioned metal-resin bonded body is suitable for use in various applications in which metal-resin bonded bodies are being used or are being considered for use.

Examples of the above 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.

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

The metal-resin bonded body can also be used in components for equipment that requires optimal heat management design, such as various home appliances, by combining the high thermal conductivity of the copper member with the insulating properties of the resin member. Examples of the above applications include home appliances such as refrigerators, washing machines, vacuum cleaners, microwave ovens, air conditioners, lighting equipment, electric water heaters, televisions, clocks, ventilation fans, projectors, and speakers, 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.

Other examples of applications include components for lithium-ion secondary batteries and robots.

The present invention will be described below with reference to examples. The scope of the present invention is not to be construed as being limited by the examples.

In the following experiments, the melting point (Tm) and glass transition temperature (Tg) of the polyamide resin were measured using the following method.

(Melting point (Tm), glass transition temperature (Tg))
The melting point (Tm) and glass transition temperature (Tg) of the polyamide resin were measured using a differential scanning calorimeter (DSC220C type, manufactured by Seiko Instruments Inc.). Specifically, about 5 mg of the polyamide resin was sealed in an aluminum pan for measurement and set in the differential scanning calorimeter. Then, the polyamide resin was heated from room temperature to 350°C at 10°C/min. In order to completely melt the resin, the resin was held at 360°C for 3 minutes, and then cooled to 30°C at 10°C/min. After being left at 30°C for 5 minutes, the resin was heated a second time to 360°C at 10°C/min. The temperature (°C) of the endothermic peak in this second heating was taken as the melting point (Tm) of the polyamide resin, and the transition point corresponding to the glass transition was taken as the glass transition temperature (Tg).

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

(Heat of fusion (ΔH))
The heat of fusion (ΔH) of the polyamide resin was determined from the area of the exothermic peak of crystallization during the first heating process in accordance with JIS K 7122 (2012).

(composition)
The composition of the modified polyolefin resin, specifically the content (mol %) of ethylene and α-olefin having 3 or more carbon atoms, and the content (mass %) of functional group structural units were measured by ¹³ C-NMR under the following measurement conditions.
Measurement device: Nuclear magnetic resonance device (ECP500 type, manufactured by JEOL Ltd.)
Observed nucleus: ^13C (125MHz)
Sequence: Single pulse proton decoupling Pulse width: 4.7 μs (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: 55 mg/0.6 mL.
Measurement temperature: 120°C
Chemical shift reference value: 27.50 ppm

(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.

(Melt Flow Rate (MFR))
The melt flow rate (MFR) of the modified polyolefin resin was measured in accordance with ASTM D1238 at 190° C. under a load of 2.16 kg, and expressed in g/10 min.

1. Synthesis/preparation of materials 1-1. Synthesis of polyamide resin (A) 2800g (24.1 mol) of 1,6-hexanediamine, 2774g (16.7 mol) of terephthalic acid, 1196g (7.2 mol) of isophthalic acid, 36.6g (0.30 mol) of benzoic acid, 5.7g of sodium hypophosphite monohydrate and 545g of distilled water were placed in an autoclave with a capacity of 13.6L and substituted with nitrogen. Stirring was started 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 raised to 3.03 MPa. After continuing the reaction for 1 hour, the low-order condensation product was discharged to the atmosphere from a spray nozzle installed at the bottom of the autoclave and extracted. After that, the low-order condensation product was cooled to room temperature, pulverized to a particle size of 1.5 mm or less with a pulverizer, and dried at 110°C for 24 hours. The resulting low-order condensate had a water content of 4,100 ppm and an intrinsic viscosity [η] of 0.15 dl/g.

Next, this low-order condensate was placed in a tray-type solid-phase polymerization apparatus, and after nitrogen replacement, the temperature was raised to 180° C. over about 1 hour and 30 minutes. Then, the reaction was continued for 1 hour and 30 minutes, and the temperature was lowered to room temperature. The intrinsic viscosity [η] of the obtained prepolymer was 0.20 dl/g.
Thereafter, the obtained prepolymer was melt-polymerized in a twin-screw extruder having a screw diameter of 30 mm and L/D=36 at a barrel set temperature of 330° C., a screw rotation speed of 200 rpm, and a resin supply rate of 6 kg/h to obtain a polyamide resin (A-1).
The resulting polyamide resin (A-1) had an intrinsic viscosity of 1.0 dl/g, a melting point (Tm) of 330° C., a glass transition temperature (Tg) of 125° C. and a heat of fusion (ΔH) of 50 J/g.

1-2. Synthesis of polyamide resin (B) 2800g (24.1 mol) of 1,6-hexanediamine, 1390g (8.4 mol) of terephthalic acid, 2581g (15.5 mol) of isophthalic acid, 109.5g (0.9 mol) of benzoic acid, 5.7g of sodium hypophosphite monohydrate and 545g of distilled water were placed in an autoclave with a capacity of 13.6L and substituted with nitrogen. Stirring was started 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 raised to 3.02 MPa. After continuing the reaction for 1 hour, the mixture was released into the air from a spray nozzle installed at the bottom of the autoclave to extract the low-order condensate. After that, the low-order condensate was cooled to room temperature, pulverized to a particle size of 1.5 mm or less with a pulverizer, and dried at 110°C for 24 hours. The resulting low-order condensate had a water content of 3,000 ppm and an intrinsic viscosity [η] of 0.14 dl/g.

Next, this low-order condensate was melt-polymerized in a twin-screw extruder having 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 supply rate of 6 kg/h to obtain a polyamide resin (B-1).
The resulting polyamide resin (B-1) had an intrinsic viscosity [η] of 0.68 dl/g, a melting point (Tm) that could not be measured, a glass transition temperature (Tg) of 125° C., and a heat of fusion (ΔH) of 0 J/g.

1-3. Synthesis of modified polyolefin resin (C) 0.63 mg of bis(1,3-dimethylcyclopentadienyl)zirconium dichloride was placed in a glass flask that had been fully purged with nitrogen, and 1.57 ml of a toluene solution of methylaminoxane (Al; 0.13 mmol/L) and 2.43 ml of toluene were added to obtain a catalyst solution. Next, 912 ml of hexane and 320 ml of 1-butene were introduced into a stainless steel autoclave with an internal volume of 2 liters that had been fully purged with nitrogen, and the temperature in 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 pressed 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 polymerization was carried out at 80°C for 30 minutes. A small amount of ethanol was introduced into the system to terminate the polymerization, and then unreacted ethylene was purged. The resulting solution was dropped into a large excess of methanol to precipitate a white solid. The white solid was collected by filtration and dried overnight under reduced pressure to obtain a white solid (ethylene-1-butene copolymer).

The ethylene content of the ethylene-1-butene copolymer was 96 mol %, the density was 0.920 g/cm ³ , the MFR (ASTM D 1238, 190° C., 2.16 kg load) was 1.0 g/10 min, and the melting point was 124° C.

100 parts by mass of the obtained ethylene-1-butene copolymer was mixed with 0.5 parts by mass of maleic anhydride and 0.04 parts by mass of peroxide (Perhexyne 25B, Nippon Oil & Fats Co., Ltd., trademark). The obtained mixture was melt-graft-modified in a single-screw extruder set at 230°C to obtain a modified polyolefin resin (C-1).

The amount of maleic anhydride grafted in the modified polyolefin resin (C-1) was measured by IR analysis and found to be 0.8% by mass, the density was 0.916 g/ ^cm3 , the MFR (ASTM D 1238, 190°C, 2.16 kg load) was 0.27 g/10 min, and the melting point (Tm) was 121°C.

1-4. Copper-based heat stabilizer (D)
A mixture of 10% by mass of copper (I) iodide and 90% by mass of potassium iodide was used as the copper-based heat stabilizer (D).

1-5. Reinforcement Glass fiber (manufactured by Nippon Electric Glass Co., Ltd., ECS03T-251H) was used as the reinforcing material.

1-6. Nucleating Agent Talc (Hifiller #5000PJ, manufactured by Matsumura Sangyo Co., Ltd.) was used as a nucleating agent.

1-7. Flow improver The following flow improvers were used.
Flow improver 1: Sodium montanate (manufactured by Clariant, LICOMONT NAV101 "LICOMONT" is a registered trademark of the company)
Flow improver 2: Calcium 12-hydroxystearate (manufactured by Nitto Kasei Kogyo Co., Ltd., CS-6CP)

1-8. Colorant A master batch containing a pigment was used as the colorant.

2. Fabrication of metal-resin bonded body 2-1. Preparation of polyamide resin composition The above materials were mixed in a tumbler blender in the composition ratio (unit: parts by mass) shown in Table 1, and melt-kneaded at a cylinder temperature of 300 to 335°C using a 30 mmφ vented twin-screw extruder. The kneaded mixture was then extruded in the form of strands and cooled in a water tank. The strands were then taken up and cut using a pelletizer to obtain a pellet-shaped polyamide resin composition.

2-2. Preparation of roughened copper member A copper alloy plate (thickness 2 mm) of alloy number C1100 specified in JIS H3100:2012 was cut to a length of 45 mm and a width of 18 mm to prepare a copper member. The copper member after degreasing was immersed in a chemical etching agent (Amalfa A-10201H, manufactured by MEC Co., Ltd.), washed with water, and immersed in a chemical etching agent in this order. Immediately after that, the member was immersed in the chemical etching agent for 4 minutes. Next, washing with water, alkaline washing (5% by mass NaOH, immersion for 20 seconds), washing with water, neutralization treatment (5% by mass H ₂ SO ₄ , immersion for 20 seconds), washing with water, rust prevention treatment (A-10290, 1 minute), and washing with water were performed in this order.

2-3. Preparation of metal-resin bonded body The copper member subjected to the surface roughening treatment was placed in a small dumbbell metal insert mold attached to an injection molding machine (manufactured by Japan Steel Works, Ltd., J55-AD). Next, the above-mentioned various polyamide resin compositions were injection molded in the mold under the conditions of a cylinder temperature of 335°C, a mold temperature of 170°C, a primary injection pressure of 90 MPa, a holding pressure of 80 MPa, and an injection speed of 25 mm/sec to prepare a test piece in which a resin member made of polyamide resin was bonded to the surface of the copper member. The bonding area between the copper member and the resin member of this test piece was 50 ^mm2 .

3. Evaluation The obtained metal-resin bonded bodies were evaluated according to the following criteria.

3-1. Bonding strength The shear bonding strength (MPa) of the prepared test pieces was measured by a method conforming to ISO 19095. Specifically, a dedicated jig was attached to a tensile testing machine (Model 1323, manufactured by Aiko Engineering Co., Ltd.), and the breaking load (N) was measured at room temperature (23°C) under the conditions of a chuck distance of 60 mm and a tensile speed of 10 mm/min. The measured breaking load (N) was divided by the area (50 mm ² ) of the bonding portion between the copper member and the resin member to obtain the shear bonding strength (MPa).

3-2. Airtightness (initial stage)
The helium leak property of the prepared test piece was evaluated by a method conforming to ISO19095. Specifically, the test piece was set in a dedicated jig capable of sealing, He gas was applied to the sealed space at a pressure of 0.1 MPa, and the He gas passing through the test piece was measured by a sniffer method using a He gas detector (HELEN M-222LD, manufactured by Canon Anelva Corporation). The airtightness was evaluated according to the following criteria based on the detected He gas flow rate (leak amount) 5 minutes after the start of detection.

◯: The detected He gas flow rate is 1×10 ⁻⁶ Pa·m ³ /s or less. △: The detected He gas flow rate is greater than 1×10 ⁻⁶ Pa·m ³ /s and less than 1×10 ⁻⁵ Pa·m ³ /s. ×: The detected He gas flow rate is greater than 1×10 ⁻⁵ Pa·m ³ /s.

3-3. Airtightness (after thermal shock test)
The He leak properties of the prepared test specimens after the thermal shock test were evaluated according to a method conforming to ISO 19095. Specifically, the prepared test specimens were subjected to a thermal shock test with a cooling and heating cycle under the following conditions, and the amount of helium leaked thereafter was measured in the same manner as in the initial airtightness evaluation described above. The airtightness after the thermal shock test was evaluated according to the following criteria, based on the ratio of the change in the amount of leak after the thermal shock test to the initial amount of leak.

(Conditions for thermal shock testing)
Temperature range: -40℃ to 150℃
Cycle conditions: -40°C, 150°C, 30 minutes each, 1 round trip, 1 cycle Number of cycles: 500

○ The change in the detected He gas flow rate is less than 1.2 times. △ The change in the detected He gas flow rate is 1.2 times or more and less than 2 times. × The change in the detected He gas flow rate is 2 times or more.

3-4. Tracking resistance Test pieces measuring 100 mm×100 mm×3 mm were prepared from each of the synthesized polyamide resins. The tracking resistance of the test pieces was evaluated in accordance with IEC60112.

The composition of the prepared polyamide resin composition, and the evaluation results of the bonding strength, airtightness (initial), airtightness (after thermal shock test), and tracking resistance of the metal-resin bonded body are shown in Table 1.

The polyamide resin composition of the present invention can firmly bond a resin member molded from the polyamide resin composition to a copper member and also improve airtightness. Therefore, the present invention is expected to broaden the applicability of metal-resin joined bodies to vehicle body parts and other components where leakage of gases, liquids, etc. is a problem, and to contribute to the further spread of metal-resin joined bodies.

Claims (10)

A copper member having a roughened surface, and a resin member containing a polyamide resin (A) bonded to the roughened surface of the copper member,
The resin member is
A polyamide resin (A) having a melting point (Tm) of 280° C. or higher as measured by differential scanning calorimetry (DSC);
A modified polyolefin resin (C) in an amount of 0.1% by mass or more and 10% by mass or less based on the total mass of the resin member;
A copper-based heat stabilizer (D) in an amount of 0.01% by mass or more and 3% by mass or less based on the total mass of the resin member;
Metal-resin bonded body. The resin member is
The content of the fatty acid metal salt relative to the total mass of the resin member is 1.3 mass% or less.
The metal-resin bonded body according to claim 1 . The polyamide resin (A) contains a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine,
The component unit (Aa) derived from a dicarboxylic acid includes a component unit derived from terephthalic acid and a component unit derived from isophthalic acid.
The metal-resin bonded body according to claim 1 or 2 . The resin member comprises the polyamide resin (A),
and a polyamide resin (B) having a heat of fusion (ΔH) of 5 J/g or less as measured by differential scanning calorimetry (DSC).
The metal-resin bonded body according to any one of claims 1 to 3 . It is an automobile part,
The metal-resin bonded body according to any one of claims 1 to 4 . A resin composition used for bonding to a roughened surface of a copper member, the roughened surface comprising:
The resin composition comprises
A polyamide resin (A) having a melting point (Tm) of 280° C. or higher as measured by differential scanning calorimetry (DSC);
A modified polyolefin resin (C) in an amount of 0.1% by mass or more and 10% by mass or less based on the total mass of the resin composition;
A copper-based heat stabilizer (D) in an amount of 0.01% by mass or more and 3% by mass or less based on the total mass of the resin composition;
Resin composition. The resin composition comprises
The content of the fatty acid metal salt relative to the total mass of the resin composition is 1.3 mass% or less.
The resin composition according to claim 6. The polyamide resin (A) contains a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine,
The component unit (Aa) derived from a dicarboxylic acid includes a component unit derived from terephthalic acid and a component unit derived from isophthalic acid.
The resin composition according to claim 6 or 7. The resin composition comprises the polyamide resin (A),
and a polyamide resin (B) having a heat of fusion (ΔH) of 5 J/g or less as measured by differential scanning calorimetry (DSC).
The resin composition according to any one of claims 6 to 8. By joining to the copper member, a metal-resin joined body for use as an automobile part can be obtained.
The resin composition according to any one of claims 6 to 9.