Polyamide resin composition, connector housing, and connector

Abstract

To provide a polyamide resin composition capable of enhancing reflow heat resistance of a thin part, and to provide a connector housing and a connector.SOLUTION: The polyamide resin composition to be used for a connector housing having a thin part with a thickness of 0.60 mm or more and 1.20 mm or less contains: a semi-aromatic polyamide resin (A) having a melting point measured by DSC of 280°C or higher; 5.0 mass% or more and 30.0 mass% or less of a bromine-based flame retardant (B); and 5.0 mass% or more and 50.0 mass% or less of a reinforcing material (C). The semi-aromatic polyamide resin (A) contains a component unit derived from terephthalic acid and a component unit derived from 1,6-diaminohexane.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a polyamide resin composition, a housing for a connector, and a connector. [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 electrical and electronic parts (e.g., connectors), and are known to produce molded articles with excellent mechanical strength.

[0003] For example, Patent Document 1 discloses a connector having a molded article made of a polyamide resin composition containing a polyamide resin and a flame retardant. According to Patent Document 1, the connector has a high glow-wire temperature.

[0004] Furthermore, Patent Document 2 discloses a polyamide resin composition containing a polyamide resin, glass fibers, and a phosphinate. According to Patent Document 2, the polyamide resin composition is used for connectors and the like, and is said to have good mechanical strength and flame retardancy.

[0005] Patent Document 3 discloses a fine-pitch electrical connector socket in which the wall forming the passage for inserting the contact pins is made of a polyamide resin composition containing a polyamide resin, a flame retardant, and a fibrous reinforcing material. According to Patent Document 3, the connector socket has good mechanical strength and flame retardancy.

[0006] Furthermore, Patent Document 4 discloses a polyamide resin composition containing a long-chain semi-aromatic polyamide resin, a flame retardant, a phosphazene, and a reinforcing material. According to Patent Document 4, the polyamide resin composition is used for connector sockets and the like. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2019-175584 [Patent Document 2] Japanese Patent Application Publication No. 2019-014913 [Patent Document 3] Special Publication No. 2017-500705 [Patent Document 4] Special Publication No. 2022-552508 Summary of the Invention [Problem to be solved by the invention]

[0008] When a molded article of a polyamide resin composition containing a semi-aromatic polyamide resin is used for a housing for a connector or the like, the molded article (housing) may be reflow soldered to a substrate. During this process, the moisture contained in the housing may evaporate due to heating in the reflow process, and the resulting vapor pressure may cause blisters (expansion) in the housing. From the viewpoint of improving the appearance and dimensional accuracy of the housing, it is desirable to use a polyamide resin composition that is less likely to cause blisters due to heating (high reflow heat resistance).

[0009] As a result of investigations, the present inventors have found that in connector housings having thin-walled portions, blisters are particularly likely to occur at the thin-walled portions.

[0010] An object of the present invention is to provide a polyamide resin composition, a housing for a connector, and a connector that can improve the reflow heat resistance of thin-walled portions. [Means for solving the problem]

[0011] In order to solve the above problems, one aspect of the present invention relates to the following polyamide resin compositions [1] and [2]. [1] A polyamide resin composition for use in a housing for a connector, having a thin-walled portion with a thickness of 0.60 mm or more and 1.20 mm or less, A semi-aromatic polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC); a brominated flame retardant (B) whose content relative to the total mass of the polyamide resin composition is 5.0 mass% or more and 30.0 mass% or less; A reinforcing material (C) whose content relative to the total mass of the polyamide resin composition is 5.0 mass% or more and 50.0 mass% or less; Including, The semi-aromatic polyamide resin (A) contains a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine, The dicarboxylic acid-derived unit (Aa) includes a terephthalic acid-derived unit, The diamine-derived component unit (Ab) includes a 1,6-diaminohexane-derived component unit. Polyamide resin composition. [2] The dicarboxylic acid-derived unit (Aa) further includes a dipic acid-derived unit. [1] The polyamide resin composition according to [1].

[0012] In order to solve the above problems, one aspect of the present invention relates to a housing for a connector as set forth in the following items [3] to [5]. [3] A housing for a connector molded from the polyamide resin composition according to [1] or [2], The thin-walled portion has a thickness of 0.60 mm or more and 1.20 mm or less. Housing for connector. [4] The thin-walled portion is formed at an end of the connector housing. [3] A housing for a connector according to the present invention. [5] The thin-walled portion includes a skin layer, The thickness of the skin layer is 50 μm or more and 500 μm or less. [3] or [4].

[0013] In order to solve the above problems, one aspect of the present invention relates to the connector described below in [6]. [6] A housing for a connector according to any one of [3] to [5]. connector. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a polyamide resin composition, a connector housing, and a connector that can improve the reflow heat resistance of thin-walled portions. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is an external view of a connector according to this embodiment and a connector housing included in the connector. [Figure 2] FIG. 2 is a cross-sectional view taken along line CC in FIG. 1, showing the configuration of the connector. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments.

[0017] 1. Polyamide resin composition The polyamide resin composition according to the present embodiment is a polyamide resin composition for use in a connector housing having a thin-walled portion with a thickness of 0.60 mm to 1.20 mm. The polyamide resin composition includes a semi-aromatic polyamide resin (A) having a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC), a brominated flame retardant (B) present in an amount of 5.0% by mass to 30.0% by mass relative to the total mass of the polyamide resin composition, and a reinforcing material (C) present in an amount of 5.0% by mass to 50.0% by mass relative to the total mass of the polyamide resin composition. In the polyamide resin composition, the semi-aromatic polyamide resin (A) includes component units (Aa) derived from a dicarboxylic acid and component units (Ab) derived from a diamine, the component units (Aa) derived from the dicarboxylic acid including component units derived from terephthalic acid, and the component units (Ab) derived from the diamine including component units derived from 1,6-diaminohexane.

[0018] As described above, the inventors have found that in connector housings having thin-walled portions, blisters are particularly likely to occur in the thin-walled portions. In response to this, the inventors have found that when a molded article of the polyamide resin composition is used in a connector housing having a thin-walled portion with a thickness of 0.60 mm or more and 1.20 mm or less, the reflow heat resistance of the thin-walled portion can be improved.

[0019] The polyamide resin composition contains a semi-aromatic polyamide resin (A) containing component units derived from terephthalic acid and component units derived from 1,6-diaminohexane. Specifically, the semi-aromatic polyamide resin (A) contains a component (hereinafter referred to as the "6T component") produced by intermolecular dehydration condensation between the carboxyl group of terephthalic acid and the amino group of 1,6-diaminohexane. The semi-aromatic polyamide resin (A) containing the 6T component has a fast crystallization rate, which allows for a thicker skin layer in a connector housing, which is a molded product of the polyamide resin composition. This thickens the skin layer even in thin-walled sections, where blisters are particularly likely to occur, and is thought to reduce the likelihood of blisters occurring due to the vapor pressure generated when moisture evaporates within the thin-walled sections.

[0020] According to the findings of the present inventors, when the thickness of the thin-walled portion is 1.20 mm or less, blisters are particularly likely to occur in the thin-walled portion. However, it has been found that the polyamide resin composition can suppress the occurrence of blisters even when the thickness of the thin-walled portion is 1.20 mm or less.

[0021] 1-1. Semi-aromatic polyamide resin (A) In this embodiment, the polyamide resin composition contains a semi-aromatic polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC). The semi-aromatic polyamide resin (A) has a high melting point, which can prevent the polyamide resin from melting during the reflow process. A method for measuring the melting point of the semi-aromatic polyamide resin (A) will be described later.

[0022] The semi-aromatic polyamide resin (A) contains component units (Aa) derived from a dicarboxylic acid and component units (Ab) derived from a diamine.

[0023] (Component unit (Aa) derived from dicarboxylic acid) The constituent units (Aa) derived from dicarboxylic acids include constituent units derived from terephthalic acid.

[0024] The content of the component units derived from terephthalic acid is preferably 40 mol% to 100 mol%, more preferably 60 mol% to 99 mol%, even more preferably 60 mol% to 85 mol%, and particularly preferably 60 mol% to 65 mol%, based on the total number of moles of the component units (Aa) derived from dicarboxylic acids. A content of 40 mol% or more reduces the water absorption of the semi-aromatic polyamide resin (A), reducing the vapor pressure when the moisture evaporates and reducing the likelihood of blistering, thereby improving the reflow heat resistance of the molded article. Furthermore, a content of 40 mol% or more increases the crystallinity of the semi-aromatic polyamide resin (A), thereby enhancing the mechanical strength of the thin-walled portion of the connector housing. This allows the thin-walled portion to withstand the vapor pressure when the moisture inside the thin-walled portion evaporates, further reducing the likelihood of blistering in the thin-walled portion. As a result, the reflow heat resistance of the thin-walled portion is further improved.

[0025] The dicarboxylic acid-derived component unit (Aa) may contain other dicarboxylic acid-derived component 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.

[0026] 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.

[0027] 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 40 mol % or less, relative to the total number of moles of the component units (Aa) derived from the dicarboxylic acid.

[0028] Examples of the alicyclic dicarboxylic acid include cyclohexanedicarboxylic acid and its esters.

[0029] Examples of aromatic dicarboxylic acids other than terephthalic acid include isophthalic acid, 2-methylterephthalic acid, and naphthalenedicarboxylic acid.

[0030] The content of component units derived from alicyclic dicarboxylic acids and aromatic dicarboxylic acids other than terephthalic acid is preferably 20 mol % or more and 80 mol % or less, and more preferably 25 mol % or more and 75 mol % or less, based on the total number of moles of component units (Aa) derived from dicarboxylic acids.

[0031] The dicarboxylic acid-derived component units (Aa) preferably contain from 60 mol % to 99 mol % of component units derived from terephthalic acid and from 1 mol % to 40 mol % of component units derived from an aliphatic dicarboxylic acid having from 4 to 20 carbon atoms, relative to the total number of moles of component units derived from the dicarboxylic acid-derived component units (Aa), and more preferably contain from 60 mol % to 85 mol % of component units derived from terephthalic acid and from 15 mol % to 40 mol % of component units derived from an aliphatic dicarboxylic acid having from 4 to 20 carbon atoms.

[0032] (Diamine-derived component unit (Ab)) The diamine-derived component units (Ab) include component units derived from 1,6-diaminohexane. The content of the 1,6-diaminohexane-derived component units is preferably 30 mol % to 100 mol %, more preferably 50 mol % to 100 mol %, and even more preferably 70 mol % to 100 mol %, based on the total number of moles of the diamine-derived component units (Ab).

[0033] The diamine-derived component unit (Ab) may include, in addition to a component unit derived from 1,6-diaminohexane, component units derived from other diamines, such as a component unit derived from an aliphatic diamine other than 1,6-diaminohexane, a component unit derived from an alicyclic diamine having from 4 to 20 carbon atoms, and a component unit derived from an aromatic diamine.

[0034] The number of carbon atoms of the aliphatic diamine other than 1,6-diaminohexane 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.

[0035] Examples of the linear alkylenediamine include 1,4-diaminobutane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, etc. Only one type of linear alkylenediamine may be contained, or two or more types may be contained.

[0036] 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. Of these, 2-methyl-1,8-diaminooctane is preferred.

[0037] Examples of the alicyclic diamine include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 2,5-bisaminomethylnorbornane, and 2,6-bisaminomethylnorbornane, etc. Examples of aromatic diamine include metaxylylenediamine, etc.

[0038] The content of the component units derived from the other diamines is preferably 0 mol % or more and 70 mol % or less, more preferably 0 mol % or more and 50 mol % or less, and even more preferably 0 mol % or more and 30 mol % or less, relative to the total number of moles of the component units (Ab) derived from the diamines.

[0039] The constituent units of the semi-aromatic polyamide resin (A) and their ratios can be calculated from the charge ratios when the semi-aromatic polyamide resin (A) is prepared, or can be measured by the NMR method.

[0040] 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.

[0041] 13 In the case of C-NMR measurement, for example, a nuclear magnetic resonance spectrometer (ECP500 model manufactured by JEOL Ltd.) is used as the measurement device, 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 13The 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.

[0042] Specific examples of the semi-aromatic polyamide resin (A) include polyamide 6T6I, polyamide 6T66, polyamide 6TDT, etc. Of these, polyamide 6T66 is preferred. That is, the semi-aromatic polyamide resin (A) preferably contains, as the dicarboxylic acid-derived component units (Aa), component units derived from terephthalic acid and component units derived from adipic acid, and contains, as the diamine-derived component units (Ab), component units derived from 1,6-diaminohexane.

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

[0044] The semi-aromatic polyamide resin (A) 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, as described in WO 03 / 085029, the semi-aromatic polyamide resin (A) can be produced by heating a dicarboxylic acid and a diamine in the presence of a catalyst to obtain a low-order condensate, and then applying shear stress to a melt of the low-order condensate to polycondense it.

[0045] The content of the semi-aromatic polyamide resin (A) is preferably 20.0% by mass or more and 80.0% by mass or less, more preferably 30.0% by mass or more and 70.0% by mass or less, and more preferably 30.0% by mass or more and 60.0% by mass or less, based on the total mass of the polyamide resin composition. When the content is 20.0% by mass or more, the mechanical strength (such as tensile strength) of the polyamide resin composition can be further increased. When the content is 80.0% by mass or less, other components such as the brominated flame retardant (B) and reinforcing material (C), which will be described later, can be sufficiently contained in the polyamide resin composition.

[0046] (Physical Properties) From the viewpoint of further increasing the mechanical strength of the connector housing, the melting point (Tm) of the semi-aromatic polyamide resin (A) is 280° C. or higher, preferably 290° C. or higher, and more preferably 300° C. or higher. Furthermore, from the viewpoint of suppressing decomposition of the amide bond of the polyamide resin (A), the melting point of the semi-aromatic polyamide resin (A) is preferably 330° C. or lower.

[0047] The melting point of the semi-aromatic polyamide resin (A) can be adjusted to the above range by adjusting the composition of the semi-aromatic polyamide resin (A). For example, the melting point can be increased by increasing the content of component units derived from terephthalic acid, which will be described later.

[0048] Furthermore, the semi-aromatic polyamide resin (A) preferably has a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of 70°C or higher and 145°C or lower, more preferably 75°C or higher and 125°C or lower, and even more preferably 80°C or higher and 100°C or lower. A glass transition temperature (Tg) of 70°C or higher increases the temperature at which molecular mobility becomes active in high-temperature environments, thereby suppressing molecular mobility and further improving the heat resistance of the polyamide resin composition and the connector housing. A glass transition temperature (Tg) of 145°C or lower makes it easier to maintain the fluidity of the resin composition without excessively increasing the mold temperature during molding, thereby improving molding processability.

[0049] The heat of fusion (ΔH) of the semi-aromatic polyamide resin (A) measured by differential scanning calorimetry (DSC) is preferably greater than 5 J / g. The heat of fusion is an indicator of the crystallinity of a resin, with a larger heat of fusion indicating higher crystallinity. When the heat of fusion (ΔH) of the semi-aromatic polyamide resin (A) exceeds 5 J / g, the crystallinity is increased, thereby enabling the mechanical strength (such as bending strength) of the resulting connector housing to be increased. Furthermore, from the viewpoint of further increasing the crystallinity of the polyamide resin (A), further increasing the mechanical strength of the connector housing, and reducing the likelihood of blister formation, the heat of fusion (ΔH) is preferably 5 J / g or greater, more preferably 30 J / g or greater. The upper limit of the heat of fusion (ΔH) is not particularly limited, but is, for example, 100 J / g.

[0050] The melting point and heat of fusion (ΔH) of the semi-aromatic polyamide resin (A) can be measured using a differential scanning calorimeter (DSC220C model, manufactured by Seiko Instruments Inc.).

[0051] Specifically, approximately 5 mg of semi-aromatic polyamide resin (A) 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 semi-aromatic 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.

[0052] The semi-aromatic polyamide resin (A) preferably has an intrinsic viscosity [η] of 0.7 dl / g to 1.2 dl / g, more preferably 0.7 dl / g to 1.0 dl / g, and even more preferably 0.7 dl / g to 0.9 dl / g, as measured in 96.5% sulfuric acid at 25°C. When the semi-aromatic polyamide resin (A) has an intrinsic viscosity [η] of 0.7 dl / g or more, the molecular weight of the polyamide resin (A) can be sufficiently increased, thereby enhancing the mechanical strength of the connector housing and the thin-walled portion. This further enhances the reflow heat resistance of the thin-walled portion. When the intrinsic viscosity [η] is 1.2 dl / g or less, the polyamide resin composition can be more effectively prevented from losing fluidity during molding. The intrinsic viscosity [η] can be adjusted by adjusting the molar ratio of the dicarboxylic acid-derived component unit (Aa) and the diamine-derived component unit (Ab). Specifically, the closer the molar ratio of the component unit (Aa) derived from carboxylic acid to the component unit (Ab) derived from diamine is to 1:1, the higher the intrinsic viscosity can be. The limiting viscosity can also be adjusted by the amount of end-capping of the polyamide resin (A).

[0053] The intrinsic viscosity [η] of the semi-aromatic polyamide resin (A) can be measured as follows. 0.5 g of the polyamide resin (A) 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

[0054] 1-2. Brominated flame retardants (B) In this embodiment, the polyamide resin composition contains a brominated flame retardant (B). This allows the polyamide resin composition and the connector housing to be imparted with flame retardancy. In this specification, the term "brominated flame retardant" refers to a bromine-containing compound that can impart flame retardancy to the polyamide resin composition.

[0055] Examples of the brominated flame retardant (B) include brominated polystyrene, polybrominated styrene, brominated polyphenylene ether, etc. Among these, the brominated flame retardant (B) is preferably brominated polystyrene or polybrominated styrene, and more preferably brominated polystyrene.

[0056] The content of the brominated flame retardant (B) is 5.0% by mass or more and 30.0% by mass or less, preferably 10.0% by mass or more and 30.0% by mass or less, and more preferably 15.0% by mass or more and 23.0% by mass or less, based on the total mass of the polyamide resin composition. By ensuring that the content is 5.0% by mass or more, the flame retardancy of the connector housing can be further improved. Furthermore, by ensuring that the content is 30.0% by mass or less, a decrease in the toughness of the connector housing can be suppressed.

[0057] 1-3. Reinforcement material (C) In this embodiment, the polyamide resin composition contains a reinforcing material (C), which can sufficiently increase the mechanical strength of the connector housing.

[0058] The reinforcing material (C) may be an inorganic filler. 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. Among these, fibrous reinforcing materials are preferred because they can easily increase the mechanical strength of the resin member. Wollastonite, glass fiber, and potassium titanate whiskers are more preferred, wollastonite and glass fiber are even more preferred, and glass fiber is particularly preferred.

[0059] The average fiber length of the fibrous reinforcing material is preferably 1 μm or more and 20 mm or less, more preferably 5 μm or more and 10 mm or less, from the viewpoints of moldability of the polyamide resin composition and the mechanical strength and heat resistance of the resulting resin part.

[0060] The cross-sectional shape of the fibrous reinforcing material may be circular or non-circular, but from the viewpoint of increasing the tensile strength of the connector casing, a circular shape is preferred.

[0061] The average fiber length and average fiber diameter of the fibrous reinforcing material 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) Disperse the filtered material obtained in 1) above in water, and measure the fiber length (Li) and fiber diameter (di) of each of 300 randomly selected fibers using an optical microscope (magnification: 50x). The number of fibers with fiber length Li is taken as qi, and the weight-average length (Lw) is calculated using the following formula, which is the average fiber length of the fibrous reinforcement. 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)

[0062] The content of the reinforcing material (C) is 5.0% by mass or more and 50.0% by mass or less, preferably 10.0% by mass or more and 45.0% by mass or less, and more preferably 20.0% by mass or more and 35.0% by mass or less, based on the total mass of the polyamide resin composition. By ensuring that the content is 5.0% by mass or more, the mechanical strength of the connector housing can be more sufficiently increased. This also ensures that the mechanical strength of the thin-walled portion can be sufficiently increased.

[0063] 1-4.Other ingredients The polyamide resin composition may contain other known components.

[0064] Examples of other components include flame retardant aids, nucleating agents, lubricants, reinforcing materials, polyolefin resins, styrene-based thermoplastic elastomers, anti-drip agents, halogen scavengers, colorants, heat stabilizers, corrosion resistance improvers, anti-drip agents, ion scavengers, elastomers (rubbers), antistatic agents, mold release agents, antioxidants (phenols, amines, sulfurs, 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.

[0065] (Flame retardant synergist) Examples of the flame retardant synergist include anhydrous sodium antimonate, hydrotalcite, boehmite, zinc stannate, iron oxide, zinc oxide, tin oxide, and the like.

[0066] 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.

[0067] (nucleating agent) The nucleating agent can promote the crystallization of the semi-aromatic polyamide resin (A), thereby further increasing the tensile strength and elastic modulus of the molded article.

[0068] 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.

[0069] 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.

[0070] The content of the nucleating agent is preferably 0.10% by mass or more and 5.00% by mass or less, and more preferably 0.10% by mass or more and 3.00% by mass or less, based on 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.

[0071] (lubricant) 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] Examples of metals constituting the above higher fatty acid metal salts include calcium, magnesium, barium, lithium, aluminum, zinc, sodium, and potassium.

[0077] Of these, the higher fatty acid metal salts are preferably calcium stearate, magnesium stearate, barium stearate, calcium behenate, sodium montanate, and calcium montanate.

[0078] 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.

[0079] (styrene-based thermoplastic elastomer) The styrene-based thermoplastic elastomer, when blended with the polyamide resin composition, improves the tensile breaking elongation, tensile breaking strength, flexural strength, flexural modulus, fluidity, etc. of the resulting connector housing.

[0080] Examples of styrene-based thermoplastic elastomers include styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), styrene-ethylene / butylene-styrene copolymer (SEBS), and styrene-ethylene / propylene-styrene copolymer (SEPS). Of these, styrene-ethylene / butylene-styrene copolymer (SEBS) is preferred from the viewpoint of improving fluidity and elongation at break.

[0081] The styrene-based thermoplastic elastomer is preferably a styrene-based thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof (preferably maleic anhydride).

[0082] (Halogen scavenger) Halogen scavengers are used as heat stabilizers and suppress discoloration and carbonization of polyamide resin compositions by capturing bromine atoms or bromine-containing compounds liberated from the brominated flame retardant (B). Examples of halogen scavengers include hydrotalcite.

[0083] 1-5. Method for producing polyamide resin composition The polyamide resin composition can be produced by a known resin mixing method, such as mixing the semi-aromatic polyamide resin (A), brominated flame retardant (B), reinforcing material (C), and other components as needed, using a Henschel mixer, V-blender, ribbon blender, or tumbler blender, or by melt-kneading the mixture in a single-screw extruder, multi-screw extruder, kneader, or Banbury mixer, followed by granulation or pulverization. The melting temperature during melt-kneading is preferably at least 10°C above the melting point (Tm) of the semi-aromatic polyamide resin (A) and at most 20°C above the melting point (Tm) of the polyamide resin (A).

[0084] 2. Connector housing and connector FIG. 1 is an external view of a connector 200 according to the present embodiment and a connector housing 100 included in the connector 200. As shown in FIG. 1, the connector 200 includes the connector housing 100. The connector housing 100 is a housing formed by molding the polyamide resin composition described above, and has a thin-walled portion 110 having a thickness of 0.60 mm or more and 1.20 mm or less. As shown in FIG. 1, the connector housing 100 may include holes 120 for arranging contact pins therein.

[0085] Furthermore, connector housing 100 may be a housing for a male connector or a housing for a female connector. In Fig. 1, connector housing 100 is a housing for a female connector, and has a fitting portion 130 (recess) for fitting with a housing for a male connector.

[0086] The location where the thin-walled portion 110 is formed is not particularly limited, but is preferably an end portion of the connector housing 100, and more preferably an end portion that serves as the flow terminal of the molten polyamide resin composition when the connector housing 100 is injection molded. In this embodiment, the thin-walled portion 110 is formed at the end portions of the connector housing 100 in the length direction (the direction of arrow A in FIG. 1 ) and the width direction (the direction of arrow B in FIG. 1 ). The connector housing 100 shown in FIG. 1 is molded by flowing a polyamide resin composition injected from the upper right to the lower left along the direction A. According to the findings of the present inventors, when a thin-walled portion 110 is formed at the end portion of the connector housing 100 using a conventional polyamide resin composition, the thickness of the skin layer in the thin-walled portion 110 tends to be particularly small, making it difficult to improve the reflow heat resistance of the thin-walled portion 110. In contrast, by forming the connector housing 100 using the above-described polyamide resin composition containing the polyamide resin (A) containing the 6T component, the skin layer can be made thick even when the thin-walled portion 110 is formed at the end. This makes it possible to improve the reflow heat resistance of the thin-walled portion 110 formed at the end. Therefore, when the thin-walled portion 110 is formed at the end, the effect of improving the reflow heat resistance of the thin-walled portion 110 becomes significant.

[0087] The number of thin-walled portions 110 included in the connector housing 100 is not particularly limited, but is, for example, two or more and four or less.

[0088] The thin-walled portion 110 includes a skin layer, and the thickness of the skin layer is preferably 50 μm or more and 500 μm or less, and more preferably 150 μm or more and 350 μm or less. A skin layer thickness of 50 μm or more can further improve the reflow heat resistance of the thin-walled portion 110. A skin layer thickness of 500 μm or less can ensure a sufficient area for the resin to flow within the mold cavity during molding, thereby maintaining good filling properties of the molten polyamide resin composition. In this specification, the term "skin layer" refers to a layer formed on the surface of a molded body that differs from the core layer formed adjacent to the skin layer inside the molded body in at least one of the crystal structure, molecular orientation, and reinforcement orientation. The thickness of the skin layer can be measured using a polarizing microscope or a scanning electron microscope.

[0089] The ratio of the thickness of the thin-walled portion 110 in the thickness direction (length of arrow D in Figure 1) to the length of the connector housing 100 (length of arrow B in Figure 1) is preferably 5% or more and 30% or less, and more preferably 10% or more and 20% or less.

[0090] The thickness of the thin-walled portion 110 (the length of the arrow D in FIG. 1) is 0.60 mm or more and 1.20 mm or less, and preferably 0.75 mm or more and 1.05 mm or less. When the thickness is 0.60 mm or more, it is possible to suppress a decrease in the mechanical strength of the thin-walled portion 110. When the thickness is 1.05 mm or less, the effect of improving the reflow heat resistance of the thin-walled portion 110 becomes more significant.

[0091] The number and size (hole diameter) of holes 120 and fitting portions 130 are not particularly limited, and are adjusted appropriately depending on the application of connector housing 100.

[0092] The connector housing 100 can be produced by a conventional melt molding method, such as injection molding, using the above-mentioned polyamide resin composition. For example, the connector housing 100 can be produced by charging the polyamide resin composition of the present invention into an injection molding machine whose cylinder temperature is adjusted to a melting point or higher of the semi-aromatic polyamide resin (A), for example, about 280°C to 350°C, to make it molten, and introducing it into a mold of a predetermined shape.

[0093] Fig. 2 is a cross-sectional view taken along line CC in Fig. 1, showing the configuration of connector 200. For the sake of explanation, Fig. 2 is shown on a scale different from that of Fig. 1. As shown in Fig. 2, connector 200 has connector housing 100 and contact pins 210 described above, but the configuration of connector 200 is not limited to this.

[0094] Examples of materials for the contact pins 210 include brass, phosphor bronze, pure copper, etc. The shape of the contact pins 210 is not particularly limited and may be any known shape.

[0095] The connector 200 can be suitably used in, for example, circuit boards included in electrical components such as LCD televisions and personal computers. [Example]

[0096] The present invention will be described below with reference to examples, which should not be construed as limiting the scope of the present invention.

[0097] 1. Synthesis / preparation of materials 1-1. Synthesis of polyamide resin 1-1-1. Synthesis of polyamide resin (A) <Polyamide resin PA-1 (6T66)> 2515 g (15.1 mol) of terephthalic acid, 2800 g (24.1 mol) of 1,6-diaminohexane, 1325 g (9.0 mol) of adipic acid, 5.7 g of sodium hypophosphite monohydrate, and 554 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 3.01 MPa. After the reaction was continued for 1 hour, the low-order condensation product was discharged into the atmosphere through a spray nozzle installed at the bottom of the autoclave and extracted. The extracted low-order condensation product was cooled to room temperature, then pulverized in a pulverizer to a particle size of 1.5 mm or less, and dried at 110°C for 24 hours.

[0098] Next, this low-order condensate was placed in a tray-type solid-state polymerization reactor, and after nitrogen substitution, the temperature was raised to 220°C over approximately 1 hour and 30 minutes. The low-order condensate was then reacted for 1 hour and cooled to room temperature. Subsequently, polyamide (high condensate) was further 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 / hour to obtain polyamide resin PA-1.

[0099] The resulting polyamide resin PA-1 had an intrinsic viscosity [η] of 0.8 dl / g, a melting point (Tm) of 320°C, and a heat of fusion (ΔH) of 50 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 62.5 mol%, the content of component units derived from adipic acid was 37.5 mol%, and the content of component units derived from 1,6-diaminohexane among component units derived from diamine was 100 mol%.

[0100] 1-1-2. Other polyamide resins <Polyamide resin PA-2 (9T)> The raw materials, 4537.7 g (27.3 mol) of terephthalic acid, 4385 g (27.5 mol) of a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [1,9-nonanediamine / 2-methyl-1,8-octanediamine = 80 / 20 (molar ratio)], 41.5 g (0.34 mol) of benzoic acid, 9.12 g of sodium hypophosphite monohydrate (0.1% by mass relative to the total mass of the raw materials), and 2.5 L of distilled water, were placed in a 20 L autoclave and purged with nitrogen. The mixture was stirred at 100 °C for 30 minutes, and the temperature inside the autoclave was raised to 220 °C over 2 hours. The pressure inside the autoclave was then raised to 2 MPa. The reaction was continued for 2 hours, and then the temperature was raised to 230°C. The temperature was maintained at 230°C for the next 2 hours, and the reaction was continued while the pressure was maintained at 2 MPa by gradually releasing the steam.

[0101] The pressure was then reduced to 1 MPa over 30 minutes, and the mixture was allowed to react for another hour, yielding a prepolymer with an intrinsic viscosity [η] of 0.15 dl / g. This was then dried at 100°C under reduced pressure for 12 hours and crushed to a particle size of 2 mm or less. This was then subjected to solid-state polymerization at 230°C and 13 Pa (0.1 mmHg) for 10 hours to yield polyamide resin PA-2.

[0102] The resulting polyamide resin PA-2 had an intrinsic viscosity [η] of 1.2 dl / g, a terminal amino group content of 40 mmol / kg, a melting point (Tm) of 300°C, and a glass transition temperature (Tg) of 125°C.

[0103] 1-2. Brominated flame retardants (B) Brominated polystyrene (SAY TEX HP-3010G, manufactured by Albemarle Corporation) was used.

[0104] 1-3. Reinforcement material (C) Glass fiber (ECS03-615, manufactured by Central Glass Co., Ltd.) was used.

[0105] 1-4.Other ingredients 1-4-1.Flame retardant synergists Anhydrous sodium antimonate (SA-A, manufactured by Nippon Seiko Co., Ltd.) was used.

[0106] 1-4-2. Lubricants Sodium montanate was used.

[0107] 1-4-3. Nucleating agent Talc (average particle size 6 μm) was used.

[0108] 1-4-4. Styrene-based thermoplastic elastomer Maleic acid modified styrene-ethylene-butylene-styrene copolymer (m-SEBS) was used.

[0109] 1-4-5. Halogen scavengers A hydrotalcite compound was used.

[0110] 2. Measurement The physical properties of each of the above resins were measured by the following methods.

[0111] <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).

[0112] <Heat of fusion (ΔH)> The heat of fusion (ΔH) of the polyamide resin was calculated from the area of ​​the exothermic peak of crystallization during the first heating process in accordance with JIS K 7122 (2012).

[0113] <Intrinsic viscosity [η]> The intrinsic viscosity [η] of the polyamide resin was calculated 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 then calculating the intrinsic viscosity [η] based on the 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

[0114] 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 Table 1, 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 and 2.

[0115] 4. Connector Fabrication Each polyamide resin composition was injection molded under the following conditions to produce a 48-pole connector measuring 70 mm long x 6 mm wide x 7 mm high. The connector had thin-walled portions with a thickness of 0.80 mm at the ends in the length and width directions. (Molding conditions) Injection molding machine: Sumitomo Heavy Industries, Ltd. SE50, cylinder temperature: melting point + 10°C, mold temperature: glass transition point + 25°C

[0116] 5. Evaluation <Reflow heat resistance of thin-walled parts> Each connector fabricated was conditioned at 40°C and 95% relative humidity for 96 hours. The conditioned specimen was placed on a 1-mm-thick glass epoxy substrate. A temperature sensor was attached to the substrate. The glass epoxy substrate with the connector mounted was placed in an air reflow soldering machine (AIS-20-82-C, manufactured by Atec Techtron Co., Ltd.) and subjected to a reflow process according to the temperature profile shown in Figure 1. As shown in Figure 1, the temperature was raised to 230°C at a predetermined rate; then, the temperature was increased to a predetermined set temperature (a: 270°C, b: 265°C, c: 260°C, d: 255°C, and e: 235°C) over 20 seconds, and then lowered to 230°C. The maximum set temperature at which the connector did not melt and no blisters formed on the thin-walled surface of the connector was determined, and this maximum set temperature was designated as the reflow heat resistance temperature.

[0117] The composition and evaluation results of each polyamide resin composition are shown in Table 1. The composition values ​​in Table 1 represent parts by mass.

[0118] [Table 1]

[0119] From the results of Polyamide Resin Composition 1, it was found that the reflow heat resistance of the thin-walled portion of the connector housing can be improved by using a polyamide resin containing the 6T component. [Industrial Applicability]

[0120] The polyamide resin composition of the present invention can suppress the occurrence of blisters in the thin-walled portion of a connector housing, and is therefore useful for, for example, electrical parts. [Explanation of symbols]

[0121] 100 Connector Housing 110 Thin-walled section 120 holes 130 fitting part 200 Connectors 210 Contact pin

Claims

1. A polyamide resin composition for use in a housing for a connector, the polyamide resin composition having a thin-walled portion with a thickness of 0.60 mm or more and 1.20 mm or less, A semi-aromatic polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC); a brominated flame retardant (B) whose content relative to the total mass of the polyamide resin composition is 5.0 mass% or more and 30.0 mass% or less; a reinforcing material (C) whose content relative to the total mass of the polyamide resin composition is 5.0 mass% or more and 50.0 mass% or less; Including, The semi-aromatic polyamide resin (A) contains a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine, The dicarboxylic acid-derived component unit (Aa) includes a terephthalic acid-derived component unit, The diamine-derived component unit (Ab) includes a 1,6-diaminohexane-derived component unit. Polyamide resin composition.

2. The dicarboxylic acid-derived component unit (Aa) further includes an adipic acid-derived component unit. The polyamide resin composition according to claim 1.

3. A housing for a connector molded from the polyamide resin composition according to claim 1, The thin-walled portion has a thickness of 0.60 mm or more and 1.20 mm or less. Housing for connector.

4. The thin-walled portion is formed at an end portion of the connector housing. The connector housing according to claim 3 .

5. the thin-walled portion includes a skin layer, The thickness of the skin layer is 50 μm or more and 500 μm or less. The connector housing according to claim 3 .

6. A connector housing according to any one of claims 3 to 5, connector.

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