JP3547911B2 - Polyester resin automotive wiring harness connector - Google Patents

Description

【００４６】
表−１より、次のことが明かである。
（１）本発明に係る自動車用ワイヤーハーネスコネクター製造用の組成物は、成形性に優れている。
（２）本発明に係る自動車用ワイヤーハーネスコネクターは、電極引き抜き強度が実用的強度としての最低値４．５Ｋｇｆ以上の値であり、電極の保持力の問題が解消できる。
（３）本発明に係る自動車用ワイヤーハーネスコネクターは、係止板挿入力が実用的強度としての最低値１．５Ｋｇｆ以上の値であり、電極の保持力の問題が解消できる。
【００４７】
（４）本発明に係る自動車用ワイヤーハーネスコネクターは、室温、低温、湿熱（高温・高湿）条件下に曝したあと、高温条件下に曝したあとにおいても、割れ・欠けの発生率が低い。
（５）これに対して、基体樹脂がＰＢＴホモポリマーのみの場合は、成分（Ｂ）と成分（Ｃ）の双方を配合しても、割れ・欠けの発生率が高く実用的ではない（比較例１参照）。
（６）基体樹脂のＰＢＴホモポリマーにワックスを添加した場合（比較例５参照）、アクリルゴムを添加した場合（比較例６参照）は、成形性が悪く、厚さ０．３５ｍｍ以下の肉薄部分を有する成形品の成形には適さない。
【００４８】
（７）基体樹脂中の共重合ＰＢＴの割合が１．５重量％と少ない場合は、コネクターの割れ・欠けの発生率が高く実用的ではない（比較例２参照）。
（８）基体樹脂中の共重合ＰＢＴの割合が１０重量％と多い場合は、コネクターの割れ・欠けの発生率は低いが、係止板挿入力が実用的強度としての最低値１．５Ｋｇｆに達成ず、実用的ではない（比較例３参照）。
（９）基体樹脂中の共重合ＰＢＴの割合が５重量％と本発明で必須とする範囲にあっても、成分（Ｂ）および／または成分（Ｃ）を含まない製品は、割れ・欠けの発生率が高く実用的ではない（比較例４参照）。
【００４９】
本発明は、次の様な特別に有利な効果を奏し、その産業上の利用価値は極めて大である。
１．本発明に係るポリエステル樹脂製自動車用ワイヤーハーネスコネクターは、原料樹脂組成物が成形性に優れているので、厚さ０．３５ｍｍ以下の薄肉部分を有する製品でも製造できる。
２．本発明に係るポリエステル樹脂製の自動車用ワイヤーハーネスコネクターは、電極引き抜き強度、係止板挿入力などが、実用的強度としての最低値以上であり、強度に優れている。
３．本発明に係るポリエステル樹脂製の自動車用ワイヤーハーネスコネクターは、室温、低温条件下で割れ・欠けの発生率が低い。従って、冬季における低温時での作業の場合にコネクターに大きな衝撃が加わった場合には、割れや欠けが発生し難く、自動車用ワイヤーハーネスコネクターの生産性を向上させることができる。
４．さらに、湿熱（高温、高湿）条件下に曝したあと、高温条件下に曝したあとにおいても、割れ・欠けの発生率が低いので、自動車のエンジンルームの高温・高湿下で衝撃を受けても、割れや欠けが生じ難い。
【図面の簡単な説明】
【図１】本発明に係るコネクターの一例の斜視図である。
【図２】図１のコネクターに電極を挿入した際の部分拡大断面図である。
【符号の説明】
１…係止板
２…ロック部
３…極間の０．３５ｍｍの薄肉部分
４…電線
５…電極
６…ランス
７…コネクター本体の外壁
８…コネクター本体の中間壁
９…電極挿入口[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a polyester resin automotive wire harness connector. More specifically, it is a component made of a composition of polybutylene terephthalate resin (hereinafter abbreviated as “PBT resin”) for connecting electric / electronic equipment circuits for automobiles, and has a thickness of 0.35 mm. The present invention relates to an automotive wire harness connector having the following parts.
[0002]
[Prior art]
Among the connectors manufactured by injection molding of a thermoplastic resin, those made of PBT resin have been used as wire harness connectors for automobiles because of their excellent heat resistance, chemical resistance and dimensional stability. 2. Description of the Related Art In recent years, the number of wire harness connectors mounted on a single vehicle has been increasing due to the addition of functions for improving the safety, comfort and running performance of the vehicle and the progress of electronics.
[0003]
On the other hand, in order to improve the fuel efficiency of automobiles, reducing the weight of a wire harness connector has become an important issue, and there is a demand for downsizing and multi-pole connectors. For this reason, it is necessary to reduce the thickness of the wall of the connector, and a PBT resin composition exhibiting good fluidity during molding is required. In order to achieve this good fluidization, conventionally, the viscosity of a PBT resin serving as a base resin of the PBT resin composition has been reduced. However, a PBT resin composition comprising a low-viscosity PBT resin is more brittle than a connector comprising a higher-viscosity PBT resin composition, and is liable to crack and chip, and is inferior in moisture-heat resistance (high humidity and high temperature). There is a disadvantage that.
[0004]
As the usage ratio of the PBT resin wire harness connector increases, cracking or chipping of the connector in the process of assembling and transporting the wire harness or attaching it to an automobile has become a serious problem. In particular, when working at a low temperature in winter or when a large impact is applied to the connector, cracking or chipping occurs, and the productivity of the wire harness connector is significantly reduced. For this reason, there is a limit in reducing the viscosity of the PBT resin described above.
[0005]
[Problems to be solved by the invention]
On the other hand, there has been proposed a method of adding various elastomer components to a PBT resin in order to improve cracking and chipping of a connector. In this method, the elastomer component is dispersed in the PBT resin in the form of small particles, thereby preventing the cracks generated by the impact from expanding and improving the impact resistance. Therefore, the elastomer component is finely dispersed in the PBT resin. Dispersion is essential. For this reason, when an elastomer component is added to a low-viscosity PBT resin, it is difficult to disperse the elastomer component, and a sufficient effect of improving impact properties cannot be obtained, or the melt viscosity of the obtained PBT composition increases, It was difficult to form a connector having a thin portion of 0.35 mm or less as intended by the present invention.
[0006]
The present invention solves the above-mentioned problems of the prior art and, despite having a thin portion of 0.35 mm or less, has little cracking and chipping, has good impact resistance, and is required for a wire harness connector for automobiles. It is an object of the present invention to provide a wire harness connector for an automobile which is excellent in various properties to be performed, that is, excellent in the holding power of an electrode, the strength after heat treatment and the strength after wet heat treatment, and the like.
[0007]
[Means for achieving the object]
In view of such circumstances, the present inventors have conducted intensive studies and as a result, since the elastic modulus is lower than that of the PBT resin, it has conventionally been considered that the holding power (pulling strength) of the electrode of the connector is reduced and the connector cannot be put to practical use. Polytetramethylene glycol (hereinafter abbreviated as "PTMG") To Copolymerization PBT resin contained as a component (hereinafter, may be abbreviated as [copolymerized PBT]) In addition, they have found that the above problems can be solved by combining a specific stabilizer, and have completed the present invention.
[0008]
That is, in order to solve the above problems, in the present invention, polytetramethylene glycol having a molecular weight of 500 to 3500 is used as a copolymer component. 5-7 100 parts by weight of the polybutylene terephthalate resin (A) containing 0.05% by weight, and 0.05 to 1 part by weight of the hindered phenol compound (B), and / or Thioether compounds (C) A polyester resin automotive wire harness connector having a thin portion having a thickness of 0.35 mm or less, which is formed from a resin composition obtained by adding 0.05 to 1 part by weight. provide.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
In the present invention, the base resin is a polybutylene terephthalate resin (A) containing 3 to 7% by weight of polytetramethylene glycol (PTMG) as a copolymer component (hereinafter abbreviated as “component (A)”). The “Component (A)” is obtained by blending a PBT homopolymer with a copolymerized polybutylene terephthalate resin containing PTMG in an amount of more than 7% by weight as a copolymer component. Ingredient content It may be a resin blended in the range of 3 to 7% by weight.
[0010]
In a connector made of a PBT homopolymer, a part of a lance holding an electrode in a predetermined position is lost when the electrode is pulled out, whereas PTMG PBT containing as a copolymer component When the base resin is used as the base resin, unlike the conventional case of adding an elastomer, cracking and chipping can be prevented without impairing the fluidity, and particularly at low temperatures, which has been a problem of the conventional PBT homopolymer connector. Cracks and chips can be greatly improved.
[0011]
When the PTMG copolymer component of the component (A) is less than 3% by weight, the effect of improving cracking and chipping is insufficient, and when the PTMG copolymer component exceeds 7% by weight, the component ( The strength of the connector decreases with the decrease in the elastic modulus of A), the wall surface is deformed by a small stress, and the lock strength decreases, which is not practically suitable. When the PTMG copolymerization component of the component (A) is 3 to 7% by weight of the component (A), there is almost no decrease in electrode holding power, and the practical strength as a connector is sufficient.
[0012]
PTMG in component (A) Copolymer component Is selected in a molecular weight range of 500-3500. If the molecular weight is outside this range, Copolymer PBT containing this The object of the present invention of preventing the connector from being cracked or chipped is not achieved, which is not preferable. PTMG Of the copolymer component A particularly preferred range of molecular weight is 650-2000.
[0013]
Component (A) is dissolved in a mixed solution of phenol and 1,1,2,2-tetrachloroethane at a weight ratio of 1: 1 at a concentration of 1 g / dl, and has an intrinsic viscosity measured at a temperature of 30 ° C. However, those having a range of 0.6 to 1.4 g / dl are preferable. If the intrinsic viscosity is less than 0.6 g / dl, it tends to crack or chip when molded into a connector and cannot withstand practical use. If the intrinsic viscosity exceeds 1.4 g / dl, the object of the present invention is to be satisfied. It is difficult to form a connector having a thin portion having a thickness of 0.35 mm or less. A particularly preferred range of the intrinsic viscosity of component (A) is from 0.7 to 1.15 g / dl.
[0014]
Conventionally, the copolymer PBT has poorer thermal stability than the PBT homopolymer, and tends to undergo thermal degradation during molding and thermal degradation during use at a high temperature. It was difficult to obtain a connector with less cracks and chips. This problem is caused, especially when molding a connector having a thin-walled portion, by trying to improve the fluidity by lowering the molecular weight of the copolymerized PBT, or by increasing the molding temperature to increase the fluidity of the copolymerized PBT. Was remarkable. In the present invention, this problem is solved by blending the hindered phenol compound (B) {also referred to as the component (B)} and / or the thiophenol compound (C) {also referred to as the component (C)}. Thus, a connector for a wire harness having a thin portion of 0.35 mm or less, preferably 0.32 mm or less, with less cracking and chipping can be obtained.
[0015]
As the hindered phenol compound (B) {component (B)}, triethylene glycol [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol- Bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] , Tetrakis [methylene-3 (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propyl] methane, 1,3,5-trimethyl-2,4,6-tris (3,5- Di-tert-butyl-4-hydroxypentyl) benzene, tris (3,5-di-tert-butyl-4-hydroxyphenyl) isocyanurate, tris-3,5-di-tert-butyl And 4-hydroxy-pen Jill) isocyanurate.
[0016]
These may be used alone or as a mixture of two or more. Among these, preferred are 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene and pentaerythrityl-tetrakis [3- (3 , 5-di-t-butyl-4-hydroxyphenyl) propionate].
[0017]
The amount of the hindered phenol compound (B) {component (B)} to be added is selected in the range of 0.05 to 1% by weight based on the component (A). If the amount added is less than this, the desired thermal stability cannot be obtained, and if it is added more, the thermal stability does not improve. A particularly preferred addition amount of the hindered phenol compound (B) is in the range of 0.1 to 0.5% by weight.
[0018]
As the thioether compound (C) {component (C)}, dilauryl thiodipropionate, ditridecyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol-tetrakis (3- Lauryl thiopropionate), pentaerythritol-tetrakis (3-dodecyl thiopropionate), pentaerythritol-tetrakis (3-octadecyl thiopropionate), pentaerythritol-tetrakis (3-myristyl thiopropionate), penta Erythritol-tetrakis (3-stearylthiopropionate) and the like.
[0019]
These may be used alone or as a mixture of two or more. Among them, preferred are pentaerythritol-tetrakis (3-laurylthiopropionate), pentaerythritol-tetrakis (3-dodecylthiopropionate), pentaerythritol-tetrakis (3-octadecylthiopropionate), It is a thioether compound having a molecular weight of 1000 or more, such as erythritol-tetrakis (3-myristylthiopropionate) and pentaerythritol-tetrakis (3-stearylthiopropionate).
[0020]
The amount of the thioether compound (C) {component (C)} to be added is selected in the range of 0.05 to 1% by weight based on the component (A). If the amount is less than this, the desired thermal stability cannot be obtained, and if it is added more, the thermal stability does not improve. A particularly preferred addition amount of the thioether compound (C) is 0.1 to 0.5% by weight.
[0021]
Improving the melt heat stability of the component (A) is possible only by adding the hindered phenol compound (B) {the component (B)}. However, when the component (A) is heated in an oxidizing atmosphere, it may be colored red to brown. Use of the thioether-based compound (C) {component (C)} in combination can prevent such coloring of the component (A) and further improve the thermal stability of the component (A). . On the other hand, if only the thiophenol-based compound (C) {component (C)} is added, the sufficient thermal stability intended for the present invention cannot be obtained.
[0022]
To add the hindered phenol compound (B) {component (B)} and / or the thioether compound (C) {component (C)} to the component (A), the component (A) )) During the polycondensation, (2) a method of adding while the polycondensation of component (A) is in a molten state after completion of polycondensation, and (3) a method of adding to component (A) in the form of pellets and melting. A kneading method may be used, and any method may be used.
[0023]
By adding the alkali metal hypophosphite before at least the polycondensation in the production process of the component (A) is completed, the thermal stability and wet heat resistance of the component (A) can be improved. As a result, cracking and chipping of the connector can be reduced, and durability under high temperature and high humidity can be improved. Examples of the alkali metal hypophosphite include sodium hypophosphite, potassium hypophosphite, lithium hypophosphite, and the like, with sodium hypophosphite being particularly desirable.
[0024]
The amount of the alkali metal hypophosphite added to the component (A) is preferably in the range of 1 to 1000 ppm. If it is less than 1 ppm, the effect of the addition cannot be sufficiently obtained, and if it is added more than 1000 ppm, the effect is not changed but the polycondensation reaction is inhibited, which is not preferable. The preferable addition amount of the alkali metal hypophosphite is in the range of 3 to 200 ppm, and particularly preferable is in the range of 5 to 80 ppm.
[0025]
The resin for manufacturing an automobile harness connector of the present invention is as described above, but the base resin is made of various kinds of resin additives that do not impair the characteristics of the automobile harness connector, as long as the characteristics are not impaired. Can be blended. Examples of resin additives that can be blended include colorants, antistatic agents, crystal nucleating agents, plasticizers, lubricants, release agents, fillers, fibrous reinforcing agents, fillers, flame retardants, flame retardant assistants, Examples include a heat stabilizer and an antioxidant.
[0026]
In order to produce a target automotive harness connector from the resin composition for producing an automobile wire harness connector, an injection molding method is generally used. When the injection molding method is used, a large number of products having the same shape with stable dimensions can be manufactured in large quantities, which is industrially advantageous.
[0027]
An automotive wire harness connector has a function of inserting an electric wire with a plurality of electrodes into the connector. The inserted connector is used as a pair of male and female. FIG. 1 is a perspective view of an example of the connector according to the present invention, and FIG. 2 is a partially enlarged sectional view when an electrode is inserted into the connector. In the drawing, 1 is a locking plate, 2 is a lock portion, 3 is a thin portion having a gap of 0.35 mm, 4 is an electrode, 6 is a lance, 7 is an outer wall of the connector body, 8 is an intermediate wall of the connector body, and 9 is This is the electrode insertion port. The electrode 5 is inserted from above the electrode insertion port 9 in FIG.
[0028]
【Example】
Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following description examples as long as the gist of the present invention is not contradicted.
In the examples described below, the intrinsic viscosity of the base resin, the moldability of the resin composition, and various characteristics of the molded product were measured by the methods described below.
[0029]
(1) Intrinsic viscosity: dissolved in a mixture of phenol and 1,1,2,2-detrachloroethane at a weight ratio of 1: 1 to a concentration of 1 g / dl, and subjected to an Ubbelohde viscometer. Used and measured at a temperature of 30 ° C.
(2) Moldability: A molded article (connector) having the shape shown in FIG. 1 was molded using a mold mounted on a FUNAC50B injection molding machine. The molding conditions were as follows.
Cylinder temperature: 225 ° C, mold temperature: 50 ° C, injection pressure: 850 Kg / cm ² Injection speed: 120 mm / sec; Injection time: 6.0 seconds; Cooling time: 7.0 seconds.
The obtained molded product was visually inspected for insufficient filling (short) and for the presence or absence of burrs, and judged as follows. Underfilling mainly occurred in a thin portion (thickness 0.3 mm) between the connectors.
：: good, △: partially underfilled, ×: remarkably underfilled.
[0030]
(3) Electrode pull-out strength: As shown in FIG. 2, an electrode with an electric wire is inserted into the molded product shown in FIG. 1, and the electrode body and the lead wire are attached to the pull of the pulling jig of the Instron universal testing machine. Then, the substrate was pulled at a speed of 200 mm / min, and the tensile strength required to pull out the electrode was measured. Practically, an electrode pull-out strength of 4.5 kgf or more is required.
(4) Locking plate insertion force: The locking plate 1 of the connector shown in FIG. 1 was compressed at a speed of 5 mm / min with an Instron universal testing machine, and the strength required for fitting was measured. Practically, a locking plate insertion force of 1.5 kgf or more is required.
[0031]
(5) Cracking and chipping: 200 molded articles shown in FIG. 1 were put in a polyethylene bag, and the bag was dropped on a steel plate from a height of 1.5 m. The dropped connector was taken out of the bag and visually observed, the number of cracks and chips was counted, and the rate of occurrence of cracks and chips (%) was calculated.
* Room temperature test: The above drop test was performed under a temperature condition of 23 ° C. Practically, it is necessary that the rate of occurrence of cracks and chips is 1.0% or less.
* Low temperature test: The molded article put in the polyethylene bag was left for 1 hour under a temperature condition of -20 ° C, and was taken out and immediately subjected to the drop test described above. Practically, it is necessary that the rate of occurrence of cracks and chips is 10% or less.
[0032]
* Moisture and heat resistance test: The molded article shown in FIG. 1 was left in an atmosphere of a temperature of 80 ° C. and a humidity of 95% for 250 hours, and then left at a temperature of 23 ° C. and a humidity of 50% for 24 hours to perform the drop test described above. . Practically, it is necessary that the rate of occurrence of cracks and chips is 10% or less.
* Heat resistance test: The molded product shown in FIG. 1 was left at 150 ° C. for 250 hours, and then left at 23 ° C. and 50% humidity for 24 hours to perform the drop test described above. Practically, it is necessary that the rate of occurrence of cracks and chips is 10% or less.
[0033]
[Example 1]
PTMG with a molecular weight of 1000 As a copolymer component 10% by weight Contained Then, 50% by weight of a copolymerized PBT having an intrinsic viscosity of 1.15 dl / g, 49.2% by weight of a PBT homopolymer having an intrinsic viscosity of 0.95 dl / g, pentaerythryl-tetrakis [3- (3,5-di- [t-butyl-4-hydroxyfell) propionate] 0.3% by weight, pentaerythritol-tetrakis- (3-laurylthiopropionate) 0.3% by weight, and paraffin wax 0.3% by weight were weighed respectively. The mixture was uniformly mixed with a blender. The obtained mixture was kneaded with a twin-screw kneading extruder and pelletized.
[0034]
Using the obtained pellets, the moldability, the molded product (connector) molded by the injection molding machine having the shape shown in FIG. The evaluation test was performed by the above method. Table 1 shows the results.
[0035]
[Example 2]
In the example described in Example 1, the PBT homopolymer was added to the oligomer before polycondensation under reduced pressure in the PBT homopolymer production process at 50 ppm based on the polymer that produced sodium hypophosphite monohydrate. Thereafter, a pellet was obtained in the same manner as in the same example except that the PBT resin was subjected to polycondensation until a predetermined intrinsic viscosity was reached.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0036]
[Example 3]
In the example described in Example 2, copolymerized PBT was converted to PTMG having a molecular weight of 1,000. As a copolymer component 10% by weight Contained In the same manner as in the above example, except that 70% by weight of the copolymerized PBT having an intrinsic viscosity of 1.15 dl / g was used and the PBT homopolymer was replaced with 29.2% by weight of a PBT homopolymer having an intrinsic viscosity of 0.95 dl / g. A pellet was obtained by the method. Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0037]
[ Comparative Example 7 ]
In the example described in Example 4, 30% by weight of a copolymerized PBT having an intrinsic viscosity of 1.15 dl / g containing 10% by weight of PTMG having a molecular weight of 1000 as a copolymer component, and a PBT homopolymer 69 having an intrinsic viscosity of 0.95 dl / g Pellets were obtained in the same manner as in Example 2 except that 0.2% by weight was used. Various evaluation tests were performed on the obtained pellets by the method described in Example 1. The results are shown in Table 1.
[0038]
[Example 5]
PTMG with a molecular weight of 1000 As a copolymer component 10% by weight Contained 50 wt% of a copolymerized PBT having an intrinsic viscosity of 1.15 dl / g, 49.4 wt% of a PBT homopolymer having an intrinsic viscosity of 0.95 dl / g, and pentaerythryl-tetrakis [3- (3,5-di-t- [Butyl-4-hydroxyphenyl) propionate] and 0.3% by weight of paraffin wax were weighed, and the mixture was uniformly mixed with a blender. The obtained mixture was kneaded with a twin-screw kneading extruder and pelletized. Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0039]
[Comparative Example 1]
99.4% by weight of a PBT homopolymer having an intrinsic viscosity of 1.10 dl / g and 0.3% by weight of pentaerythryl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]; 0.2% by weight of pentaerythritol-tetrakis- (3-laurylthiopropionate) and 0.3% by weight of paraffin wax were each weighed and uniformly mixed with a blender to obtain a mixture. The obtained mixture was kneaded with a twin-screw kneading extruder and pelletized.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0040]
[Comparative Example 2]
In the example described in Comparative Example 1, PTMG having a molecular weight of 1000 was used as the base resin. As a copolymer component 3% by weight Contained Pellets in the same manner as in the same example, except that the modified PBT was replaced with 50 wt% of a copolymerized PBT having an intrinsic viscosity of 1.00 dl / g and 49.2 wt% of a PBT homopolymer having an intrinsic viscosity of 0.95 dl / g. Got.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0041]
[Comparative Example 3]
In the example described in Comparative Example 1, PTMG having a molecular weight of 1000 was used as the base resin. As a copolymer component 10% by weight Contained A pellet was obtained in the same manner as in the same example except that 99.2% by weight of the copolymerized PBT having an intrinsic viscosity of 1.15 dl / g was used.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0042]
[Comparative Example 4]
PTMG with a molecular weight of 1000 As a copolymer component 10% by weight Contained 50% by weight of the copolymerized PBT having an intrinsic viscosity of 1.15 dl / g, 49.2% by weight of a PBT homopolymer having an intrinsic viscosity of 0.95 dl / g, and 0.3% by weight of paraffin wax are each weighed and uniformly mixed by a blender. The resulting mixture. The obtained mixture was kneaded with a twin-screw kneading extruder and pelletized.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0043]
[Comparative Example 5]
99.4% by weight of a PBT homopolymer having an intrinsic viscosity of 1.20 dl / g, 0.3% by weight of pentaerythryl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 0.2% by weight of pentaerythritol-tetrakis- (3-laurylthiopropionate) and 0.3% by weight of paraffin wax were each weighed and uniformly mixed with a blender to obtain a mixture. The obtained mixture was kneaded with a twin-screw kneading extruder and pelletized.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0044]
[Comparative Example 6]
94.4% by weight of PBT homopolymer having an intrinsic viscosity of 1.10 dl / g, 5% by weight of a core shell type acrylic rubber, pentaerythryl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate 0.3% by weight, 0.2% by weight of pentaerythritol-tetrakis- (3-laurylthiopropionate) and 0.3% by weight of paraffin wax were each weighed to form a mixture that was uniformly mixed by a blender. . The obtained mixture was kneaded with a twin-screw kneading extruder and pelletized.
Various evaluation tests were performed on the obtained pellets by the method described in Example 1. Table 1 shows the results.
[0045]
[Table 1]

[0046]
From Table 1, the following is clear.
(1) The composition for producing a wire harness connector for an automobile according to the present invention has excellent moldability.
(2) In the wire harness connector for an automobile according to the present invention, the electrode withdrawal strength is equal to or more than the minimum value of 4.5 kgf as a practical strength, and the problem of the electrode holding force can be solved.
(3) In the wire harness connector for an automobile according to the present invention, the insertion force of the locking plate is equal to or more than the minimum value of 1.5 kgf as a practical strength, and the problem of the electrode holding force can be solved.
[0047]
(4) The automotive wire harness connector according to the present invention has a low rate of occurrence of cracks and chips even after being exposed to room temperature, low temperature, and wet heat (high temperature and high humidity) conditions, and even after being exposed to high temperature conditions. .
(5) On the other hand, when the base resin is only the PBT homopolymer, even if both the component (B) and the component (C) are blended, the rate of occurrence of cracks and chips is high and not practical (comparative). See Example 1).
(6) When wax is added to the PBT homopolymer of the base resin (see Comparative Example 5) and when acrylic rubber is added (see Comparative Example 6), the moldability is poor, and the thin portion having a thickness of 0.35 mm or less is poor. Is not suitable for molding of molded articles having
[0048]
(7) When the proportion of the copolymerized PBT in the base resin is as small as 1.5% by weight, the rate of occurrence of cracks and chips in the connector is high and not practical (see Comparative Example 2).
(8) When the proportion of the copolymerized PBT in the base resin is as large as 10% by weight, the rate of occurrence of cracking and chipping of the connector is low, but the insertion force of the locking plate is reduced to a minimum value of 1.5 kgf as a practical strength. Not achieved and not practical (see Comparative Example 3).
(9) Even if the proportion of the copolymerized PBT in the base resin is 5% by weight, which is an essential range in the present invention, a product not containing the component (B) and / or the component (C) has cracks and chips. The occurrence rate is high and not practical (see Comparative Example 4).
[0049]
The present invention has the following particularly advantageous effects, and its industrial utility value is extremely large.
1. According to the present invention Made of polyester resin Automotive wire harness connectors Since the raw resin composition is excellent in moldability, A product having a thin portion having a thickness of 0.35 mm or less can be manufactured.
2. Made of the polyester resin according to the present invention For cars The wire harness connector is excellent in strength, as the electrode withdrawal strength, the insertion force of the locking plate, and the like are at least as low as practical strength.
3. Made of the polyester resin according to the present invention For cars Wire harness connectors have low rates of cracking and chipping at room and low temperature conditions. Therefore, when a large shock is applied to the connector when working at low temperatures in winter, cracks and chips are less likely to occur, For cars The productivity of the wire harness connector can be improved.
4. Furthermore, even after exposure to wet heat (high temperature and high humidity) conditions, even after exposure to high temperature conditions, the incidence of cracking and chipping is low. However, cracking and chipping are unlikely to occur.
[Brief description of the drawings]
FIG. 1 is a perspective view of an example of a connector according to the present invention.
FIG. 2 is a partially enlarged sectional view when an electrode is inserted into the connector of FIG.
[Explanation of symbols]
1 ... locking plate
2… Lock part
3: 0.35 mm thin part between the poles
4: Electric wire
5 ... Electrode
6 ... Lance
7 ... Outer wall of the connector body
8 ... Intermediate wall of the connector body
9 ... Electrode insertion port

Claims (2)

0.05 to 1 part by weight of a hindered phenol compound (B) is added to 100 parts by weight of a polybutylene terephthalate resin (A) containing 5 to 7 % by weight of polytetramethylene glycol having a molecular weight of 500 to 3500 as a copolymer component, and And / or a polyester resin having a thin portion with a thickness of 0.35 mm or less, characterized by being formed from a resin composition obtained by adding 0.05 to 1 part by weight of a thioether compound (C). Automotive wire harness connector. The component (A) is a polytetramethylene glycol copolymerized polybutylene terephthalate resin produced by adding 1 to 1000 ppm of an alkali metal hypophosphite before at least the polycondensation in the production process is completed. Item 4. A polyester resin automotive wiring harness connector according to Item 1.

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