JPH0779027B2 - connector - Google Patents

Description

TECHNICAL FIELD The present invention relates to a connector for connecting an electric / electronic device circuit, which is excellent in heat resistance and mechanical properties.

<Prior Art> Conventionally, various plastic connectors have been used to connect electrical and electronic equipment circuits. As the density of electrical and electronic equipment has increased, connectors have become smaller and thinner,
Excellent plasticity and dimensional accuracy are required for plastics as connector materials. Furthermore, as a method of soldering electrical and electronic components such as connectors to printed wiring boards, the conventional pin-placing method is rapidly shifting to surface mounting technology (hereinafter abbreviated as SMT), and connectors and the like are more numerous than before. High heat resistance is required for the electric and electronic parts of

In order to meet such demands, for example, JP-A-64-72404
Japanese Patent Publication discloses a connector formed by molding wholly aromatic polyester.

<Problems to be Solved by the Invention> However, even a connector made of wholly aromatic polyester disclosed in JP-A-64-72404 does not have sufficient heat resistance in the sense that it is SMT compatible, and the connector has a pin. It was found that cracks occur when press-fitting. Further, it has been found that there is a problem that the fluidity at the time of molding is not always sufficient.

Therefore, the present invention is not only excellent in formability and dimensional accuracy but also SM.
An object of the present invention is to provide a connector for electrical / electronic device circuit connection, which has heat resistance that can be used for T applications and excellent toughness that does not cause cracks or cracks against stress when press-fitting a pin.

<Means for Solving Problems and Problems> As a result of intensive investigations by the present inventors to achieve the above problems,
The present inventors have found that a connector formed by molding a liquid crystal polyester having a characteristic structure and a composition mainly composed of a liquid crystal polyester having a specific structure meets the object of achieving the above-mentioned object, and arrived at the present invention.

That is, the present invention provides (1) the following structural units (I), (II), (III) and (I
V) and structural unit [(I) + (II)] is [(I) +
75 to 95 mol% of (II) + (III)] and 25 to 5 mol% of the structural unit (III) of [(I) + (II) + (III)],
A connector formed by molding a liquid crystal polyester having a structural unit (I) / (II) molar ratio of 75/25 to 95/5, and _{O-R 1 -O ...... (II} ) O-CH 2 CH 2 -O ...... (III) CO-R 2 -CO ...... (IV) ( provided that in the formula R ₂ is one or more groups selected from And one or more groups selected from Further, X in the formula represents a hydrogen atom or a chlorine atom. (2) A connector according to item (1), further comprising 0.2 to 30 parts by weight of an organic flame retardant with respect to 100 parts by weight of the liquid crystal polyester according to item (1).

The structural unit (I) is a structural unit of polyester produced from p-hydroxybenzoic acid, and the structural unit (II) is
4,4'-dihydroxybiphenyl, hydroquinone, 2,6
-A structural unit formed from one or more aromatic diols selected from dihydroxynaphthalene, t-butylhydroquinone, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl and phenylhydroquinone, Structural unit (III) is a structural unit formed from ethylene glycol, structural unit (IV) is terphthalic acid, 4,4'-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid,
1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid, 1,2-bis (2-chlorophenoxy) ethane-4,4 '
Each represents a structural unit formed from one or more aromatic dicarboxylic acids selected from dicarboxylic acids and 4,4'-diphenyl ether dicarboxylic acids.

Of these, R ₁ is But for R ₂ Is most preferred.

Among the structural units (I) to (IV), the structural unit [(I)
+ (II)] is 75 to 95 mol% of [(I) + (II) + (III)], preferably 82 to 92 mol%, and more preferably 85 to 90 mol%. The structural unit (III) is 25 to 5 mol% of [(I) + (II) + (III)],
It is preferably 18 to 8 mol%, more preferably 15 to 10 mol%. Structural unit [(I) + (II)] is [(I) +
If it is more than 95 mol% of (II) + (III)], the melt fluidity is lowered and it is solidified at the time of polymerization, and if it is less than 75 mol%, the heat resistance becomes poor, which is not preferable. Further, the structural unit (I) /
(II) molar ratio is 75 / 25-95 / 5, preferably 78 / 22-
It is 93/7. If it is less than 75/25 or more than 95/5, the heat resistance and fluidity are poor, and the object of the present invention cannot be achieved. The structural unit (IV) is substantially equimolar to the structural unit [(II) + (III)].

The method for producing the liquid crystal polyester used in the present invention is not particularly limited, and it can be produced according to a known polyester polycondensation method.

The liquid crystal polyester used in the present invention has a melt viscosity of 10
-15,000 poises are preferred, and 20-5,000 poises are particularly preferred.

The melt viscosity is a value measured by a Koka flow tester under conditions of (liquid crystal starting temperature + 40 ° C) and shear rate of 1,000 (1 / sec).

On the other hand, the logarithmic viscosity of this liquid crystal polyester is 0.1 g / dl concentration 6
It can be measured in pentafluorophenol at 0 ℃,
0.5 to 5.0 dl / g is preferable, and 1.0 to 3.0 dl / g is particularly preferable.

When polycondensing the liquid crystal polyester used in the present invention, in addition to the components constituting the structural units (I) to (IV), isophthalic acid, 3,3′-diphenyldicarboxylic acid,
Aromatic dicarboxylic acids such as 2,2'-diphenyldicarboxylic acid, adipic acid, azelaic acid, sebacic acid, aliphatic dicarboxylic acids such as dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone, methyl Aromatic diols such as hydroquinone, 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxybenzophenone, 4,4′-dihydroxydiphenyl ether, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, Aliphatic and alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid, or aromatic imide compounds A small proportion that does not impair the object of the present invention It can be allowed to further copolymerization.

The liquid crystal polyester used in the present invention can be imparted with flame retardancy by adding an organic flame retardant. When the flame retardancy is required for the purpose and purpose of the connector of the present invention, It is preferable to add an organic flame retardant and use it as a flame-retardant liquid crystal polyester composition.

The organic flame retardant that can be used in the present invention is an organic bromine compound and / or an organic phosphorus compound, and the organic bromine compound has a bromine atom in the molecule, and the organic bromine compound has a bromine content of 20% by weight or more. Are preferred. Specifically, low molecular weight organic bromine compounds such as decabromodiphenyl ether, ethylene bis- (tetrabromophthalimide), brominated polycarbonate (for example, a polycarbonate oligomer produced from brominated bisphenol A as a raw material or a copolymer thereof with bisphenol A). ), A brominated epoxy compound (for example, a diepoxy compound produced by the reaction of brominated bisphenol A with epichlorohydrin or a monoepoxy compound obtained by the reaction of brominated phenols with epichlorohydrin), poly (brominated benzyl acrylate),
Brominated polyphenylene ether, brominated bisphenol A, condensate of cyanuric chloride and brominated phenol, halogenated polymers or oligomers such as brominated polystyrene, crosslinked brominated polystyrene, crosslinked brominated poly α-methylstyrene, or a mixture of Among them, ethylene bis- (tetrabromophthalimide), brominated epoxy oligomer or polymer, brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and brominated polycarbonate are preferable, and ethylene bis- (tetrabromophthalimide) is particularly preferable. , Brominated polystyrene and brominated polycarbonate can be particularly preferably used.

The addition amount of these organic flame retardants is preferably 0.2 to 30 parts by weight, more preferably 0.5 to 20 parts by weight, per 100 parts by weight of the liquid crystal polyester, but the flame retardancy is the structural unit (III) of the liquid crystal polyester. Since it is closely related to the copolymerization amount, the following addition amounts are preferable. That is, the amount of the organic bromine compound added is preferably 60 to 280 parts by weight, and particularly preferably 100 to 200 parts by weight, based on 100 parts by weight of the structural unit (III) in the liquid crystal polyester.

On the other hand, the organic phosphorus compound used in the present invention has a phosphorus atom in the molecule, and is a compound phosphine synthesized from phosphoric acid, phosphorous acid, phosphonic acid, or the like,
The compounds include compounds such as phosphine oxide and phosphorane, compounds having the following structural formulas, and polymers containing at least one of these compounds.

Examples of this polymer include polymers having the following structural units.

The most preferable organic phosphorus compound among these is the following polymer.

A part of these organic phosphorus compounds may be a metal salt. The addition amount of the organophosphorus compound is represented by the structural formula (I),
0.2 to 30 parts by weight, preferably 0.5 to 1 part by weight based on 100 parts by weight of the liquid crystalline polyester comprising (II), (III) and (IV)
5 parts by weight of the structural unit (III) in the liquid crystal polyester
2 to 150 parts by weight per 100 parts by weight is preferred, 10 to 100
Part by weight is especially preferred.

Further, in the present invention, the organic phosphorus compound may be an organic phosphorus compound containing bromine such as a polymer having the following structural unit.

In the liquid crystal polyester of the present invention, the structural unit (III) is 5 to 25 mol% of the structural unit [(I) + (II) + (III)], and the above-mentioned flame retardant is added in the vertical combustion test of UL94 standard. According to (ASTM D790 standard), it is possible to make it V-0 at a thickness of 1/32 ″. When the structural unit (III) is less than 5 mol%, the melting point of the liquid crystal polyester becomes high, so that the liquid crystal polyester is decomposed when melted by the flame retardant. However, the polymerization is deteriorated, the mechanical properties are deteriorated even if the filler is added, and the molded product is drip-burned, which is not preferable.
When I) is more than 25 mol%, not only the heat resistance such as deflection temperature under load is greatly deteriorated, but also it is necessary to add a large amount of organic bromine compound or phosphorus compound to impart flame retardancy, or antimony compound. Since it is necessary to further add a flame retardant auxiliary such as, heat resistance and mechanical properties are greatly reduced, which is not preferable.

A composition in which a filler is further contained in the liquid crystal polyester and the flame-retardant liquid crystal polyester composition used in the present invention is more preferably used in the present invention. When the filler is added, the addition amount thereof is preferably 200 parts by weight or less, and particularly preferably 15 to 100 parts by weight, relative to 100 parts by weight of the liquid crystal polyester.

As the filler that can be used in the present invention, glass fiber, carbon fiber, aromatic polyamide fiber, potassium titanate fiber, gypsum fiber, brass fiber, stainless fiber,
Steel fiber, ceramic fiber, boron whisker fiber, mica, talc, silica, calcium carbonate, glass beads, glass flakes, glass microballoons, clay, wollastonite, titanium oxide, etc. fibrous, powdery, granular or plate-like inorganic Examples include fillers.

Among the above fillers, glass fiber is preferably used. The type of glass fiber is not particularly limited as long as it is generally used for reinforcing a resin, and for example, long fiber type or short fiber type chopped strand, milled fiber or the like can be selected and used. Further, the glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin, a coupling agent such as a silane type or a titanate type, and other It may be treated with a surface treatment agent.

Furthermore, the composition of the present invention contains an antioxidant and a heat stabilizer (for example, hindered phenol, hydroquinone, phosphites and their substitution products), and UV absorption within a range that does not impair the object of the present invention. Agents (eg resorcinol, salicylate, benzotriazole,
Benzophenone, etc., lubricants and mold release agents (such as montanic acid and its salts, its esters, its half esters, stearyl alcohol, stearamide and polyethylene wax), dyes (eg nitrosium) and pigments (eg cadmium sulfide, phthalocyanine, etc.)
It is possible to add a predetermined property by adding a normal additive such as a colorant including carbon black), a plasticity, an antistatic agent, or another thermoplastic resin.

The resin composition of the present invention is preferably melt-kneaded, and a known method can be used for melt-kneading. For example, using a Banbury mixer, a rubber roll machine, a kneader, a single-screw or twin-screw extruder, and the like, the composition can be melt-kneaded at a temperature of 200 to 350 ° C to obtain a composition.

The connector of the present invention can be easily obtained by injection molding the above liquid crystal polyester or flame retardant liquid crystal polyester composition (a filler may be added if necessary).

<Example> Hereinafter, the present invention will be described in detail with reference to Examples.

Reference Example 1 881 parts by weight of p-hydroxybenzoate, 158 parts by weight of 4,4'-dihydroxybiphenyl, 907 parts by weight of acetic anhydride, 141 parts by weight of terephthalic acid and 245 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g. A reaction vessel equipped with a stirring blade and a distilling tube was charged, and deacetic acid polycondensation was performed under the following conditions.

First, in a nitrogen gas atmosphere at 100-250 ° C for 5 hours, 250-300
After reacting for 1.5 hours at 300 ℃, 0.5mmHg at 300 ℃ for 1 hour
When the pressure was reduced to room temperature and the reaction was further continued for 2.25 hours to complete the polycondensation, an approximately theoretical amount of acetic acid was distilled off to obtain a resin (a) having the following theoretical structural formula.

Also, place this polyester on the sample stage of the polarizing microscope,
The temperature was raised and the optical anisotropy was confirmed. As a result, the liquid crystal starting temperature was 264 ° C., indicating good optical anisotropy. The logarithmic viscosity of this polyester (measured in pentafluorophenol at a concentration of 0.1 g / dl at 60 ° C) is 1.96 dl / g, 30
The melt viscosity at 4 ° C and the shear rate of 1,000 (1 / sec) was 910 poise.

Example 1 100 parts by weight of the resin (a) obtained in Reference Example 1 and brominated polystyrene ("Pyrocheck" 68PB manufactured by Nissan Ferro Co., Ltd.) 8.5
45 parts by weight of glass fiber were melt-mixed and pelletized by a 30 mmφ twin-screw extruder set at 300 ° C.

The obtained composition was subjected to an injection molding machine, and then 10 × 3 × 3 mm, 8
× 2 rows of 16-pin connectors were molded.

The obtained connector was completely filled up to the thin portion, and no sink mark or blistering was observed. Also, when a solder heat resistance test (immersion test) of this connector was performed,
No blistering or deformation was observed even after immersing at 280 ° C for 10 seconds, showing that the heat resistance was excellent. Further terminals (pins)
When a press-fit test was conducted, no cracks were found, and it was found that the strength and toughness were excellent.

<Effects of the Invention> According to the present invention, a connector for electrical / electronic circuit connection having excellent toughness, strength, dimensional accuracy, and extremely high heat resistance that can be used for surface mounting can be obtained.

Claims (2)

[Claims] 1. A structural unit [(I) + (II)] consisting of the following structural units (I), (II), (III) and (IV) is [(I) + (II) + (III)]. Of the structural unit (III) is 25 to 5 mol% of [(I) + (II) + (III)], and the molar ratio of the structural unit (I) / (II) is 75/95%. 25-9
A connector formed by molding 5/5 liquid crystal polyester. _{O-R 1 -O ...... (II} ) O-CH 2 CH 2 -O ...... (III) CO-R 2 -CO ...... (IV) ( provided that in the formula R ₂ is one or more groups selected from And one or more groups selected from Further, X in the formula represents a hydrogen atom or a chlorine atom. ) 2. The connector according to claim 1, further comprising 0.2 to 30 parts by weight of an organic flame retardant with respect to 100 parts by weight of the liquid crystal polyester.