JP3048734B2 - connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connector for circuit connection of electric and electronic equipment having excellent heat resistance and mechanical properties, and more particularly to a novel connector comprising an aromatic polyester having a specific structure and a fibrous reinforcing agent. The present invention relates to a connector formed by molding a resin composition.

[0002]

2. Description of the Related Art Conventionally, various plastic connectors have been used for connection of electric / electronic equipment circuits. Electrical·
As the density of electronic devices has increased, connectors have become smaller,
The resin as a connector material is required to be thinner and to have excellent moldability and dimensional stability. On the other hand, methods for soldering electrical and electronic components such as connectors to a printed wiring board are different from the conventional pin setting method using surface mounting technology (S
MT), and electrical and electronic components such as connectors are required to have higher heat resistance than ever before.

[0003] In response to such demands, various heat-resistant resins,
So-called engineering plastics are under consideration. Of these, polyphenylene sulfide has good fluidity and dimensional accuracy, but still has insufficient heat resistance, and has a problem in toughness such as cracking when a pin is pressed into a connector. High melting point polyamides such as nylon 4,6 and terephthalic acid / isophthalic acid / hexamethylenediamine copolymerized polyamide have excellent toughness and improved heat resistance, but have a large dimensional change due to moisture absorption. There is a problem that molding is difficult due to poor melt stability. On the other hand, terephthalic acid and cyclohexane 1,4-
Resins mainly composed of polyester with dimethanol have been studied, but this is not sufficiently stable at the time of melting like the above-mentioned polyamide, and furthermore the oxidation stability is extremely poor,
For example, there is a problem that the toughness of a molded product is likely to be reduced by heating during solder reflow. Liquid crystalline polyester, so-called LCP, has good fluidity and excellent heat resistance, but has a large difference in physical properties between the resin flow direction and the lateral direction, that is, large anisotropy, and low weld strength. It is difficult to apply to a molded article whose part is formed into a large number.

[0004]

The object of the present invention is to improve the moldability,
An object of the present invention is to provide a connector formed by molding a novel resin composition having excellent mechanical properties, heat resistance, and dimensional stability.

[0005]

That is, the present invention provides the following formulas (I) and (I)
I) and (III)

[0006]

Embedded image

And the equivalent ratio of component (II) to component (III) is 60 / 40-90.
The connector is formed by molding a resin composition comprising 95 to 30% by weight of an aromatic polyester having a ratio of 10/10 and 5 to 70% by weight of a fibrous reinforcing material having an aspect ratio of 10 or more.

The polymer constituting the resin composition of the present invention is a polyester consisting essentially of the components of the above formulas (I), (II) and (III). Component (II) and component (III)
Is from 60/40 to 90/10. If the content equivalent ratio is out of this range, Tm is too high and molding becomes difficult, and conversely, Tm becomes low and heat resistance becomes insufficient, which is not preferable.

The method for producing the polymer is not particularly limited. For example, a method (A) in which diphenyl isophthalate, hydroquinone and 4,4'-dihydroxydiphenyl are heated and polycondensed in the presence of a catalyst, Diacetoxyhydroquinone and 4,4'-diacetoxydiphenyl by heating in the presence of a catalyst to effect polycondensation (B), wherein isophthalic acid, hydroquinone and 4,4'-dihydroxydiphenyl contain substituents (C) heating and polycondensation in the presence of a good phenol and a catalyst. In the case of the above method (B), diacetoxyhydroquinone,
Instead of using 4,4'-diacetoxydiphenyl,
An acetoxylation reaction can also be carried out in a polymerization reaction system using hydroquinone, 4,4'-dihydroxydiphenyl and acetic anhydride. As the method for producing the polymer of the present invention, the method (C) can be preferably used.

The above method (C) is a method for obtaining a polyester by esterification and transesterification, and can be roughly divided into two reactions, an initial reaction and a polymerization reaction.

The initial reaction is at least 50 carboxyl groups.
% Is a stage where it reacts with the hydroxy component and is esterified. In this stage, water is generated by the reaction, and is distilled out of the reaction system. At this stage, it is necessary to prevent the phenol component from distilling out of the reaction system.

The next polymerization reaction is a stage in which the esterification further progresses, and at the same time, the exchange reaction between the ester of the carboxylic acid component and the phenol component and the other hydroxy component proceeds so that the polymerization proceeds. At this stage, the phenol component is distilled out of the reaction system together with the water. The initial reaction and the polymerization reaction cannot be clearly distinguished from each other, but are distinguished in that the phenol component is positively suppressed from being distilled out of the reaction system in the initial reaction and is distilled off in the polymerization reaction.

Although the reaction temperature of the initial reaction varies depending on the catalyst, it is 150 ° C. or higher, preferably 180 ° C. or higher, particularly preferably 230 ° C. or higher, and is preferably raised as the reaction proceeds. In this case, the upper limit is 330 ° C., preferably about 300 ° C.

The initial reaction can be carried out under normal pressure to pressurization, but when the boiling point of the phenol component at normal pressure is particularly lower than the reaction temperature, the reaction is preferably performed under pressurized conditions. The reaction system is preferably set in an atmosphere of an inert gas such as nitrogen or argon.

The reaction time may be a time sufficient for the above-mentioned ester reaction to proceed sufficiently, and this time varies depending on the reaction time, the reaction scale and the like, but it is 30 minutes to 20 hours, preferably about 1 to 10 hours. It is.

In the above reaction, it is preferable to remove the water generated by the esterification out of the reaction system. The esterification reaction is an equilibrium reaction, and as the generated water is removed out of the system, the reaction proceeds, and the yield and purity of the product are improved. The generated water can be removed out of the reaction system by the difference in boiling point from the phenol component, but can also be removed out of the reaction system by azeotropy using an organic solvent which forms an azeotropic mixture with water. . The organic solvent may be any organic solvent which does not decompose itself under the reaction conditions, is substantially stable in the reaction system, and azeotropes with water. Specifically, aromatic hydrocarbons such as toluene, xylene, and ethylbenzene can be preferably used.

The conversion of the esterification reaction in the initial reaction is preferably 50% or more. This esterification reaction rate can be known from the amount of water generated by the reaction, but for more accurate determination, it is also possible to take out a part of the reaction product and measure it by measuring the unreacted-COOH value. it can.

The esterification rate in the initial reaction is more preferably 60% or more, particularly preferably 70% or more. The reaction temperature in the polymerization reaction is from the initial reaction temperature to 38.
It is preferably carried out at 0 ° C. Since the melting point of the reactant increases as the polymerization proceeds, it is preferable to perform the reaction while gradually increasing the temperature.
To a degree preferably carried out at a temperature of not more than 330 ° C.,
In the case of a higher temperature, the melt polymerization is carried out at a temperature of 380 ° C, more preferably 360 ° C or less.

Since the aromatic polyester obtained by the method of the present invention has a relatively high melt viscosity, when the degree of polymerization is increased by melt polymerization, it is preferably carried out in a ruder type reactor or the like.

The polymerization reaction is carried out under reduced pressure or by flowing an inert gas to forcibly remove water and phenol components formed as a result of the reaction and, if necessary, excess dihydroxyaromatic compounds such as hydroquinone outside the reaction system. While doing.

The intrinsic viscosity of the polyester obtained by the method of the present invention is preferably from 0.3 to 1.5, more preferably from 0.4 to 1.2.

The resin composition of the present invention comprises the above-mentioned aromatic polyester and a fibrous reinforcing material.

Here, as the fibrous reinforcing material, glass fiber,
Examples thereof include carbon fibers, aramid fibers, silicon carbide fibers, alumina fibers, and potassium titanate fibers. The fibrous reinforcing material needs to have an aspect ratio of 10 or more. Here, the aspect ratio is the ratio between the length of the fiber and its diameter. When there is a distribution in the aspect ratio of the reinforcing fiber, the average value is defined as the aspect ratio of the fiber. If the aspect ratio is less than 10, the reinforcing effect on mechanical properties, heat resistance and the like becomes insufficient, which is not preferable. As the fibrous reinforcing material, glass fiber is preferable among the above fibers.

As these fibrous reinforcing materials, those having surface treatment agents such as coupling agents and sizing agents suitably applied are preferably used in order to improve the affinity with the aromatic polyester or the handleability of the fibers themselves.

The proportion of the aromatic polyester and the fibrous reinforcing material used is 95 to 30% by weight of the aromatic polyester and 5 to 70% by weight of the reinforcing fibers. The mixing ratio is preferably 90 to 40% by weight of the aromatic polyester and 10 to 60% by weight of the reinforcing fiber, and particularly preferably 85 to 50% by weight of the aromatic polyester and 15 to 50% by weight of the reinforcing fiber.

The composition of the present invention may contain, if necessary, a nucleating agent, a lubricant, a release agent, an antioxidant, an ultraviolet absorber, a pigment,
A plasticizer, an antistatic agent, a powdery, granular, or plate-like inorganic filler may be appropriately added.

The mixing of the above components can be carried out by a conventionally known compounding method by melt kneading.

The connector of the present invention can be obtained by molding the above resin composition by a conventionally known injection molding method.

[0029]

The aromatic polyester of the present invention can be produced industrially and advantageously at a very low cost because it can be produced by a melt polymerization method using inexpensive raw materials.
Further, the obtained polymer is a crystalline polymer having a melting point of 300 ° C. or more, and the resin composition of the present invention comprising this and a fibrous reinforcing material has heat resistance, mechanical properties, flame retardancy, chemical resistance,
It is excellent in moldability, and the connector of the present invention obtained by molding the same has extremely good solder heat resistance.

[0030]

The present invention will be described in detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. `` Parts '' in the examples
Means “parts by weight”, and the intrinsic viscosity of the polymer is a mixed solvent of p-chlorophenol / tetrachloroethane (weight ratio: 6).
0/40) at 35 ° C. The melting point (Tm) and glass transition point (Tg) of the polymer are DS
The measurement was performed at a heating rate of 10 ° C./min using C.

[0031]

Example 1 166 parts of isophthalic acid, 9 of hydroquinone 9
9 parts, 28 parts of 4,4'-dihydroxydiphenyl, 94 parts of phenol and 0.09 part of antimony trioxide were charged into a reactor equipped with a stirrer and a distilling system.
Heated to ° C. The reaction was carried out for 5 hours while gradually reducing the pressure from 5 kg / cm ² to 2 kg / cm ² and distilling water generated by the reaction out of the system. During this time 29 parts of water were produced. Next, the pressure of the reaction system was returned to normal pressure, and the reaction was carried out for 60 minutes while distilling volatile components out of the system in a nitrogen stream. During this time, the reaction temperature was raised from 280 ° C to 340 ° C.

Then, the inside of the system was gradually evacuated, and after 60 minutes, the reaction was carried out under a high vacuum of about 0.5 mmHg for 50 minutes to obtain a polymer having an intrinsic viscosity of 0.52.

Next, using an L / D42 30 mmφ co-rotating twin-screw extruder having two vent holes capable of vacuuming, a polymer temperature of 350 to 360 ° C., a screw rotation speed of 100 rpm, and an average residence time in the vacuum zone of approximately 10
The polymer was subjected to a melt reaction under the conditions of minutes. On this occasion,
In each extruder, two vent ports were maintained at a vacuum of about 1 mmHg by providing a screw section in the opposite direction to a normal transport screw at each of the vent ports and sealing the vacuum zone. The polymer obtained by the melting reaction had an intrinsic viscosity of 0.72, a Tm of 348 ° C., and a Tg of
164 ° C.

[0034]

Example 2 Aromatic polyester produced in Example 1 and chopped strands of glass fiber having a length of 3 mm (Asahi Fiberglass, 03JA PX-1, aspect ratio 2)
30) was blended and melt-blended using a 30 mm φ different direction rotating biaxial extruder under the conditions of a polymer temperature of 360 ° C. and an average residence time of about 2 minutes.

Using an injection molding machine (Model N40A, Nippon Steel Works, Ltd.), the obtained compound was heated to a cylinder temperature of 360.
Injection molding under the condition of ℃, mold temperature 160 ℃, 20 × 5 ×
5 mm, 12 × 2 rows of 24-pin connectors were molded.

The obtained connector was completely filled up to the thin portion, and no sink marks, blisters and burrs were observed.

[0037]

Example 3 Next, a heat resistance test by infrared reflow was performed using the above connector. (Infrared reflow device, TPF-15 manufactured by Asahi Engineering). The temperature was raised at a temperature of 100 to 150 ° C. for about 80 seconds, and then the temperature was raised to a peak temperature of 280 ° C., 300 ° C., and 320 ° C., and the surface was observed. Table 1 shows the results. Melting on the surface,
The case where there was no damage such as blistering or deformation was marked with “○”, and the case where damage was clearly recognized was marked with “×”.

[0038]

[Table 1]

Table 1 shows, as a comparison, the results of a heat resistance test on a connector obtained by molding a PPS resin (Ryton R-4, manufactured by Philips) at a cylinder temperature of 320.degree. C. and a mold temperature of 140.degree. As described above, it can be seen that the heat resistance of the connector of the present invention is extremely higher than that of the connector made of PPS.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-28221 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 67/00-67/03

Claims (2)

(57) [Claims] (1) The following formulas (I), (II) and (III): 95 to 30% by weight of an aromatic polyester having a content equivalent ratio of component (II) to component (III) of 60/40 to 90/10, and a fibrous material having an aspect ratio of 10 or more. A connector formed by molding a resin composition comprising 5 to 70% by weight of a reinforcing material. 2. The fibrous reinforcing material is glass fiber.
Connector as described.