JPH06192407A - Liquid crystalline polyester - Google Patents

Abstract

PURPOSE:To provide a polyester having improved mechanical characteristics, solder resistance, hydrolysis resistance, and electrical characteristics by specifying the molar fractions of structural units, concn. of terminal groups, and melt viscosity. CONSTITUTION:Terephthalic acid, 2,6-naphthalenedicarboxylic acid, methylhydroquinone, and 4,4'-dihydroxydiphenyl are copolymerized in the presence of a catalyst under a reduced pressure of 1mmHg or higher at 270-340 deg.C to give the polyester which comprises structural units of formulae I to V in molar fractions satisfying relations VI to XI, respectively, and which has molecular terminals mainly comprising CH3COO- and -COOH groups in concns. satisfying relations XII and XIII {wherein [CH3COO-] and [-COOH] are the respective concns.}, respectively, and a melt viscosity (measured at 320 deg.C under a shear rate of 1,000sec<-1>) of 30P or higher.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a liquid crystalline polyester. More specifically, the present invention is a liquid crystal capable of providing an injection-molded article having excellent mechanical properties and having solder resistance, generation of a gas such as acetic acid which is very small, and hydrolysis resistance. Responsive polyester. The injection-molded article according to the present invention is suitable as a surface mount technology (SMT) compatible electronic component material, particularly used as a relay component or a connector component, or as a sealing material for semiconductors or hybrid ICs. Furthermore, it is also excellent in electrical characteristics such as high frequency characteristics, volume resistivity, and dielectric breakdown strength.

[0002]

2. Description of the Related Art Liquid crystalline polyester has been expanding its market as a unique engineering plastic by taking advantage of its characteristics such as high fluidity, high elastic modulus, high strength, low linear expansion coefficient and good dimensional accuracy. Furthermore, the wholly aromatic liquid crystalline polyester is endowed with heat resistance due to the above characteristics.
It is also expanding into the field of electronic materials compatible with MT and the field of semiconductor-related encapsulation such as IC.

[0003]

However, when used in parts such as relays, such liquid crystalline polyesters generate a large amount of gas, which causes abnormalities in the electric system and corrosion. was there. Further, in the sealing field, there is a problem that the hydrolysis resistance, which is a problem due to polyester, is inferior and, for example, it cannot withstand the PCT (pressure cooker test) evaluation.

Further, there are problems that the adhesion with metal is deteriorated and that electric characteristics such as dielectric breakdown strength are insufficient. For them, a method of sealing the end with a monofunctional compound has been proposed, but there are problems that the polymerization rate is significantly reduced and the monofunctional compound is generated as a gas. It was In addition, there is a problem that the adhesion with metal is deteriorated.

On the other hand, there is also a method of extending the chain by using bisoxazoline or carbodiimide to improve the hydrolysis resistance, but it causes a decrease in heat resistance or causes unreacted substances to generate gas. There was a problem of doing.

[0006]

Means for Solving the Problems The inventors of the present invention have earnestly studied a polymer having solder heat resistance, reducing gas generation amount, and having hydrolysis resistance and adhesion to metal. The present inventors have found that a liquid crystalline polyester having the structure of (1) achieves the above object, and has reached the present invention.

That is, the gist of the present invention consists of structural units represented by the following chemical formulas (1) to (5), and when these mole numbers are represented by [1] to [5], the respective structural units are mole fraction satisfies the formula below (I) ~ (VI) of, and end groups mainly CH ₃ COO- group and -CO
It is composed of OH groups, and the concentration of each terminal group is [CH ₃ C
OO-] and [-COOH] each satisfy the following formulas (VII) to (VIII), and the melt viscosity measured under the conditions of a temperature of 320 ° C and a shear rate of 1000 sec ^-1. The liquid crystalline polyester is characterized by having a poise of 30 poises or more.

[0008]

[Chemical 2]

[0009]

[Equation 2] Hereinafter, the present invention will be described in detail.

First, the structural unit of the liquid crystalline polyester of the present invention will be described. The liquid crystalline polyester of the present invention comprises the structural units represented by the chemical formulas (1) to (5) shown above. The total mole fraction of the structural units (1) and (2) needs to be in the range that satisfies the above mathematical formula (I). A liquid crystalline polyester having a total molar fraction of less than 0.15 has poor fluidity and mechanical properties, and a liquid crystalline polyester having a total molar fraction of more than 0.30 has poor heat resistance. The total mole fraction is 0.
The range of 20 to 0.25 is more preferable.

The structural unit represented by the chemical formula (1) is effective in increasing heat resistance and elastic modulus, and the structural unit represented by the chemical formula (2) improves hydrolysis resistance and mechanical strength. Effective to increase. From the viewpoint of reducing the cost of raw materials, it is preferable that the ratio of the structural unit represented by the chemical formula (1) is high. In order to obtain these effects in a better balance, structural units (1) and (2)
Must be in a range that satisfies the above formula (II). This mole fraction is more preferably in the range of 0.5 to 0.95 within the range defined by the above formula (II).

The total molar fraction of the structural units (3) and (4) must be within the range that satisfies the above formula (III). The liquid crystalline polyester having a total molar fraction of less than 0.15 has poor fluidity and mechanical properties, and the liquid crystalline polyester having a total molar fraction of more than 0.30 has poor heat resistance. The total mole fraction is preferably in the range of 0.20 to 0.27 in the mole fraction defined by the formula (III).
The range of 0.21 to 0.25 is more preferable.

Further, the structural unit represented by the chemical formula (3) improves the elastic modulus and strength in both the flow direction (MD) and the direction perpendicular to the flow direction (TD) of the resin in injection molding in a well-balanced manner. Effective in increasing heat resistance,
There is also an advantage that the number of terminal carboxyl groups can be easily increased. The structural unit represented by the chemical formula (4) has an effect of improving heat resistance and strength and elongation. In order to obtain these effects in a more balanced manner, it is necessary that the structural units (3) and (4) are in a range that satisfies the above mathematical formula (IV). This mole fraction is more preferably in the range of 0.1 to 0.5 within the range defined by the above formula (IV).

Further, the structural units (1) to (4) are required to be in a range satisfying the above mathematical formula (V). This mole fraction is within the range defined by the above formula (V).
The range of 0.85-0.97 is preferable, and 0.88-0.
The range of 95 is more preferable. With such a ratio, the concentration of the end groups can be calculated according to the formulas (VII) and (VIII), respectively.
Can be satisfied, which has the effect of reducing the amount of gas generated and improving the hydrolysis resistance and the adhesion to metal.

The molar fraction of the structural unit (5) can be calculated by the formula (V
It must be within the range that satisfies I). A liquid crystalline polyester in which the mole fraction of the structural unit (5) is less than 0.50 has low heat resistance, and a liquid crystalline polyester having a molar fraction in excess of 0.68 has poor fluidity and mechanical properties. The above total mole fraction is more preferably in the range of 0.50 to 0.60 in the mole fraction defined by the above formula (VI).

A feature of the present invention is that each terminal group [CH ₃ COO-] and [-COO] is used in the terminal group quantification method described later.
H] is a liquid crystalline polyester satisfying the above formulas (VII) to (VIII), and basically has few terminal acetoxy groups (CH ₃ COO-groups) and many terminal carboxyl groups (-COOH groups). It is preferable. Further, it is preferable that the terminal phenyl group is substantially absent.

The concentration of the terminal acetoxy group is the above (VII)
It is necessary to be in a range that satisfies the formula of
(Eq / 10 ⁶ g) or less is more preferable, and 2 to 10 (e
The most preferred range is q / 10 ⁶ g). When the number of terminal carboxyl groups is more than 30 (eq / 10 ⁶ g), the amount of generated gas is large, which is not preferable, and the PCT evaluation (hydrolysis resistance) described later is not good, and the volume resistivity and dielectric breakdown are also low. There is a problem that the voltage drops.

The concentration of the terminal carboxyl group needs to be in the range satisfying the formula (VIII), preferably 150 to 500 (eq / 10 ⁶ g), more preferably 180 to 400 ( eq / 10 ⁶ g), most preferably 200 to 350 (eq / 10 ⁶ g).
Terminal carboxyl group concentration is 120 (eq / 10 ⁶ g)
If it is smaller, the generated gas increases, and surprisingly, the hydrolysis resistance (at PCT 121 ° C.) deteriorates, and the electrical characteristics such as decrease in volume resistivity and dielectric breakdown voltage occur. In addition, the adhesion with the metal also deteriorates.

Next, the method for producing the liquid crystalline polyester of the present invention will be described. In the production of the liquid crystalline polyester of the present invention, the polymerization mode is not particularly limited, and for example, an interfacial polymerization method, a solution polymerization method, a melt polymerization method or the like can be appropriately adopted. However, it is difficult to obtain a liquid crystalline polyester having a high degree of polymerization by the interfacial polymerization method or the solution polymerization method because the raw material components have poor solubility. Therefore, the melt polymerization method is particularly recommended.

A preferred manufacturing method in the present invention is as follows:
The following methods (A) to (C) based on the melt polymerization method may be mentioned. (A) Method of producing by deacetic acid polycondensation reaction from acetate compound and acid compound (B) Method of producing by deacetic acid polycondensation reaction after adding acetic anhydride to phenolic compound and acid compound to react (C) Method of producing from phenolic compound and phenyl ester compound of acid by dephenolization polycondensation reaction Among the above-mentioned melt polymerization methods, in the method (C), a phenol end is formed, so that phenol gas is easily generated. The generation of phenol gas causes contact failure in the use of liquid crystalline polyester as an electronic component material.

Therefore, from this point of view, (C)
The method (A) or (B) is more preferable than the method, and the method (B) is particularly recommended in view of the polymerization rate and the cost of raw materials. Regarding the production method of these (A) or (B),
In particular, it is preferable to adopt the method shown in the following (a) or (b). (A) As a raw material,

[0022]

Embedded image MO-Ar ₁ -OM (6) HOOC-Ar ₂ -COOH (7) MO-Ar ₃ -COOH (8) (M represents H- and / or CH ₃ CO-, and Ar ₁ is the following. (A) and / or (b), Ar ₂ represents (c) and / or (d), and Ar ₃ represents (c).)

[0023]

[Chemical 4]

[0024]

[Chemical 5]

However, when the molar numbers of (6), (7) and (8) are [6], [7] and [8], during the charging,
[6] / [7] <1. More preferably,
[6] / [7] ≦ 0.97, particularly preferably [6] /
[7] ≦ 0.95.

(B) Similar to the method of (a) above, (6), (7) and (8) are used as raw materials, but a part of [6] is intended to be used at the time of heating and / or polymerization. To be distilled out. By adopting these methods (a) and (b),
[-COOH] Many, it is possible to produce a [CH ₃ COO-] is small polyester.

In the case of the method (b), positively distilling (6) shortens the time of the temperature rising step after acetylation, or allows nitrogen gas to flow during the temperature rising. It can be done by It is also preferable to increase the initial depressurization rate of the reduced pressure polymerization. In this case, (6) is generally a diacetate product. That is,

[0028]

Embedded image CH ₃ COO—Ar ₁ —OCOCH ₃

It is in the form of. In this case, Ar ₁ is the above (a) and / or (b), but especially in the case of (a), since the diacetate has a low melting point, it is distilled out of the system as a liquid rather than as a solid. It is preferable that problems such as clogging of the pipe do not occur, and if it is used within the range defined above, it is preferable from the viewpoint of physical properties and manufacturing.

In the conventionally known method, the terminal carboxyl group and the terminal acetoxy group are substantially

[0031]

[Equation 3] [-COOH] ≈ [CH ₃ COO-]

In the case of a wholly aromatic liquid crystalline polyester, particularly in the case of the composition and composition ratio as shown in the present application, if the number of terminal carboxyl groups is extremely increased, the hydrolysis resistance is improved, and when heated. It has not been known at all that the amount of gas generated from the product decreases. For example, Japanese Patent Laid-Open No. 2-10
2223 describes a liquid crystalline polyester having the same composition and composition ratio as in the present application, but the polymer composition ratio is such that the number of diols and the number of dicarboxylic acids are equal, that is, [-CO
OH] ≈ [CH ₃ COO-],
Further, neither hydrolysis resistance nor generated gas is described at all. However, in this application

[0033]

[Number 4] [- COOH] >> [CH ₃ COO-]

By adopting the above, it was possible to surprisingly improve the hydrolysis resistance and significantly reduce the generated gas. Regarding the method for producing the liquid crystal polyester of the present invention,
When the method (B) is adopted, the raw materials (6) and (7)
(8) is added, then acetic anhydride (hereinafter referred to as (9)) is added, and acetylation is first performed at 100 to 170 ° C. At this time, it is preferable to set [6] ≦ [7].

The reaction time is 5 minutes to 3 hours, preferably 20 minutes to 1.5 hours. And the number of moles of acetic anhydride

[9] is

[0036]

[Equation 5]

It is Also in this case, the preferable lower limit value and the preferable upper limit value are 1.1 and 1.4, respectively. Further, the reaction can be carried out without a catalyst, and a catalyst may be added if necessary.

Next, the temperature is raised up to the polymerization temperature, and the pattern of this temperature rise is also important. When the method (a) described above is performed, it is preferable to raise the temperature slowly, and especially 200 to
At 260 ° C., it is preferable that the temperature is maintained for 1 to 3 hours (ripening step) once to several times. On the other hand, when performing the method (b), it is preferable to raise the temperature as fast as possible.

Next, the polymerization reaction will be described. After completion of the acetylation reaction, the temperature is raised to carry out the polymerization reaction. Polymerization temperature is 2
70-340 degreeC, Preferably it is 290-320 degreeC, Most preferably, it is 290-305 degreeC. When the polymerization reaction is performed under reduced pressure, for example, when gradually reducing the pressure from 760 mmHg to 1 mmHg, the time required for this is 60 minutes or more, preferably 2 hours or more when the method (a) is performed, Particularly, it is preferable to gradually reduce the pressure from 50 mmHg to 1 mmHg.

On the other hand, when the method (b) is adopted, it is preferable that the time is within 2 hours, particularly within 60 minutes, and 50 mm.
It is preferable to reduce the pressure from Hg to 1 mmHg as quickly as possible. Further, in any case, after the completion of the polymerization reaction, solid phase polymerization may be carried out if necessary to increase the degree of polymerization. Further, the degree of polymerization can be increased by using a horizontal polymerization reactor.

The polymerization reaction can be carried out without a catalyst, but may be carried out in the presence of a catalyst if necessary. As the catalyst, a transesterification catalyst, a polycondensation catalyst, and an acylation catalyst are used, and these may be mixed and used. Preferred catalysts include Ti (OBu) ₄ , BuSnOOH,
Sn (OAc) ₂ , Sb ₂ O ₃ , Fe (acac) ₃ ,
Zn (OAc) ₂ , Co (OAc) ₂ , Mn (OAc)
₂ , KOAc, Fe (acac) _{2 and the} like.

The amount of the catalyst used is 0 to 5000 ppm, preferably 0 to 1000 pp, based on the polymer produced.
m, and more preferably 0 to 300 ppm. It is preferable not to use a catalyst because electrical characteristics such as insulation are improved. However, when a polymerization rate is to be increased, it is preferable to use a catalyst. The melt viscosity of the liquid crystalline polyester of the present invention needs to be 30 poise or more when measured under the conditions of a temperature of 320 ° C. and a shear rate of 1000 sec ⁻¹ .

However, the polyester of the present invention is
By exhibiting liquid crystallinity, its melt viscosity is generally low.
For example, the melt viscosity measured under the above conditions is 5000
Below poise. Therefore, the melt viscosity of the liquid crystal polyester of the present invention is preferably 50 to 3000 poise, more preferably 100 to 2500 poise. Most preferably, it is 100 to 1500 poise.

Since the polyester of the present application has the characteristics described above (including high flowability), it has good moldability and can be subjected to general melt molding such as extrusion molding, injection molding and compression molding. is there. Therefore, it can be easily processed into molded articles, films, fibers and the like. In particular, when injection molding is performed, there is a feature that the generated gas is small and the hydrolysis resistance is excellent. Moreover, it is suitable for thin-walled molded products and precision molded products because it has less burrs and excellent dimensional accuracy. For example, it is used for SMT compatible electronic component materials, especially relay components, connector components, bobbins, It is suitable for semiconductor encapsulation and hybrid ICs.

The liquid crystalline polyester of the present invention includes fibers such as glass fibers and carbon fibers, fillers such as talc, mica and calcium carbonate, nucleating agents, pigments, antioxidants,
It is also possible to impart desired properties to the molded product by adding a lubricant, a stabilizer, a filler such as a flame retardant or the like, an additive, a thermoplastic resin or the like. Furthermore, a composition having both advantages of the liquid crystalline polyester of the present invention and another polymer can be obtained by blending with another polymer or alloying.

Particularly in terms of dimensional accuracy, the polyester of the present invention can exert excellent effects when 20 to 50 parts by weight of fibers such as glass fibers are added.

[0047]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In the following examples, physical properties were measured and molded by the following methods. (1) Solution viscosity (ηinh) A pentafluorophenol / o-dichlorobenzene mixed solvent (1: 1 weight ratio) was used at a temperature of 30 ° C and a concentration of 0.
It was measured under the condition of 1 g / dl.

(2) The melt viscosity was measured using a Shimadzu flow tester (cylinder nozzle length / diameter = 20) at 320 ° C. shear rate 10
It was set to 00 sec ^-1 . (3) Optical anisotropy (liquid crystallinity) It was observed using a polarizing microscope with a hot stage.

(4) Terminal group quantification method First, the liquid crystalline polyester of the present invention was crushed, and a large excess of n-propylamine was added to the crushed sample.
Process for minutes. From the main chain,

[0050]

Embedded image HO-Ar₁-OH, ₇ H₃Cn-NH-CO-Ar₂-CO-NH-nC₃
H₇, HO-Ar₃-CO-NH-nC₃H₇

Etc., n-propylacetamide from the acetate terminal and from the carboxylic acid terminal,

[0052]

Embedded image _{HOOC-Ar 2 -CO-NH-} nC 3 H 7, HO-Ar 3 -COOH

Is generated. Therefore, the liquid crystalline polyester is decomposed with n-propylamine, and the GC method and HP are used.
By the LC method, it is possible to separate the decomposition product generated from the terminal from the decomposition product derived from the main chain, and to quantify the terminal group from the peak intensity thereof.

The GC method is used to quantify the end of the acetate. The decomposition product, n-propylacetamide, at the end of the acetate is detected by GC separately from other components. Prepare a calibration curve using standard n-propylacetamide,
It quantified by the absolute calibration method. The HPLC method is used to quantify the carboxylic acid terminal. Carboxylic acid terminal decomposition product p-
Hydroxybenzoic acid, terephthalic acid mono-n-propylamide and 2,6-naphthalenedicarboxylic acid n-propylamide are detected separately from other components by HPLC. A calibration curve was prepared using standard p-hydroxybenzoic acid, terephthalic acid mono-n-propylamide and 2,6-naphthalenedicarboxylic acid mono-n-propylamide, and quantified by the absolute calibration method.

(5) Molding Molding was carried out using a J5S type 0.1 oz injection molding machine manufactured by Japan Steel Works. (6) Tensile properties Tensile elastic modulus and tensile strength were measured by the Toyo Baldwin Co.
It measured using ENSILON / UTM (III) L.

(7) Hydrolysis resistance A sample molded at 0.1 oz was put in a pressure cooker tester and tested at 121 ° C. under 2 atmospheres of saturated steam for 100 hours. With respect to the test sample, the strength retention rate of the tensile test and the solution viscosity retention rate were evaluated.

(8) Gas analysis A washed vial bottle is charged with a chipped polymer and capped, and heat-treated in an oven at 200 ° C. for 1 hour.
A part of this was injected into the GC to quantify the components. (9) Composition ratio analysis method A methanol solution of tetramethylammonium hydroxide was added to the pulverized polymer, and the polymer was pyrolyzed using pyrolysis GC to quantify the components.

Example 1 A reactor equipped with a stirring blade, a pressure reducing port, and a nitrogen introducing port was added with 4,
26.81 g of 4'-dihydroxydiphenyl (0.14
4 mol), 2.98 g (0.02 g) of methylhydroquinone
4 mol), terephthalic acid 19.94 g (0.120 mol), 2,6-naphthalenedicarboxylic acid 12.97 g
(0.060 mol) and p-hydroxybenzoic acid 58.
After charging 05 g (0.420 mol) and replacing the atmosphere with nitrogen under reduced pressure, sealing with nitrogen was carried out, and 96.48 g (0.9
45 mol). Under stirring, the polymerization tube was immersed in an oil bath at 145 ° C., reacted for 1 hour, heated to 240 ° C. over 1.5 hours, held there for 2 hours, and then heated up to 300 ° C. over 1 hour. The temperature was raised. Then, the pressure was reduced from atmospheric pressure to 1 mmHg over 2.5 hours at that temperature, and then the reaction was continued for 1 hour to complete the polymerization reaction. The evaluation results are shown in Tables 1 and 2.

Comparative Example 1 Starting material was 4,4'-dihydroxydiphenyl 26.81.
g (0.144 mol), methylhydroquinone 4.47
g (0.036 mol), terephthalic acid 19.94 g
(0.120 mol), 2,6-naphthalenedicarboxylic acid 12.97 g (0.060 mol), p-hydroxybenzoic acid 58.05 g (0.420 mol) and acetic anhydride 9
Example 1 except that the amount was 9.54 g (0.975 mol).
I went the same way. The evaluation results are shown in Tables 1 and 2.

Comparative Example 2 The starting material was 4,4'-dihydroxydiphenyl 26.81.
g (0.144 mol), methylhydroquinone 5.21
g (0.042 mol), terephthalic acid 19.94 g
(0.120 mol), 2,6-naphthalenedicarboxylic acid 12.97 g (0.060 mol), p-hydroxybenzoic acid 58.05 g (0.420 mol) and acetic anhydride 10
Example 1 except that the amount was 1.07 g (0.990 mol).
I went the same way. The evaluation results are shown in Tables 1 and 2.

Example 2 A reactor equipped with a stirring blade, a pressure reducing port and a nitrogen introducing port was added with 4,
16.76 g of 4'-dihydroxydiphenyl (0.09
0 mol), 9.68 g (0.07 g) of methylhydroquinone
8 mol), terephthalic acid 22.93 g (0.138 mol), 2,6-naphthalenedicarboxylic acid 9.08 g
(0.042 mol) and p-hydroxybenzoic acid 58.
After charging 05 g (0.420 mol) and replacing the atmosphere with nitrogen under reduced pressure, sealing with nitrogen was carried out, and 96.48 g (0.9
45 mol). Under stirring, the polymerization tube was immersed in an oil bath at 145 ° C., reacted for 1 hour, heated to 240 ° C. over 1.5 hours, held there for 2 hours, and then heated up to 300 ° C. over 1 hour. The temperature was raised. Then, the pressure was reduced from atmospheric pressure to 1 mmHg over 2.5 hours at that temperature, and then 3
The polymerization reaction was completed by reacting for 0 minutes. The evaluation results are shown in Table 1,
Shown in 2.

Example 3 The raw material was 4,4'-dihydroxydiphenyl 31.28.
g (0.168 mol), terephthalic acid 14.95 g
(0.090 mol), 19.46 g (0.090 mol) of 2,6-naphthalenedicarboxylic acid, 58.05 g (0.420 mol) of p-hydroxybenzoic acid and acetic anhydride 9
Example 2 except that 6.48 g (0.945 mol) was used.
I went the same way. The evaluation results are shown in Tables 1 and 2.

Example 4 In a reactor equipped with a stirring blade, a pressure reducing port and a nitrogen introducing port,
26.81 g of 4'-dihydroxydiphenyl (0.14
4 mol), 2.98 g (0.02 g) of methylhydroquinone
4 mol), terephthalic acid 26.91 g (0.162 mol), 2,6-naphthalenedicarboxylic acid 3.89 g
(0.018 mol) and p-hydroxybenzoic acid 58.
After charging 05 g (0.420 mol) and replacing the atmosphere with nitrogen under reduced pressure, sealing with nitrogen was carried out, and 96.48 g (0.9
45 mol). While stirring, the polymerization tube was immersed in an oil bath at 145 ° C., reacted for 1 hour, heated to 240 ° C. over 1.5 hours, held there for 2 hours, and then heated up to 300 ° C. over 1 hour. The temperature was raised. Then, the pressure was reduced from atmospheric pressure to 1 mmHg over 2.5 hours at that temperature to complete the polymerization reaction.

Next, this polymer was made into chips and was placed under reduced pressure for 2 minutes.
Solid phase polymerization was carried out at 60 ° C. for 15 hours. The evaluation results are shown in Tables 1 and 2.

[0065]

[Table 1] Table 1 ──────────────────────────────────── Example 1 Comparative Example 1 Comparative Example 2 Example 2 Example 3 Example 4 ──────────────────────────────────── <Each structural unit Mol number> [1] 19.8 20.0 20.1 23.0 15.2 27.1 [2] 10.2 10.0 9.9 7.0 14.8 2.9 [3] 3.8 5.7 6.7 12.9 0 4.0 [4] 24.0 24.0 24.0 15.0 28.0 24.0 [5] 70.0 70.0 70.0 70.0 70.0 70.0 < Structural Unit Molar Fraction and Terminal Group Concentration> (I) Formula 0.23 0.23 0.23 0.23 0.23 0.23 (II) Formula 0.67 0.67 0.67 0.77 0.50 0.90 (III) Formula 0.22 0.23 0.23 0.22 0.22 0.22 (IV) Formula 0.14 0.19 0.22 0.46 0 0.14 (V) formula 0.93 0.99 1.02 0.93 0.93 0.93 (VI) formula 0.55 0.54 0.54 0.55 0.55 0.55 (VII) formula 4 105 157 10 13 6 (VIII) formula 236 133 80 258 246 252 ────────── ────────────────── ───────

[0066]

[Table 2] (Note) Melt viscosity was measured at 350 ° C. in Example 4 and 320 ° C. in other examples.

[0067]

INDUSTRIAL APPLICABILITY The liquid crystalline polyester of the present invention not only has excellent mechanical properties and solder resistance, but also produces little gas and is excellent in hydrolysis resistance and electrical properties. It is suitable for use in injection molded articles.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 5, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0049

[Correction method] Change

[Correction content]

(4) Terminal group quantification method First, the liquid crystalline polyester of the present invention was crushed, a large excess of n-propylamine was added to the crushed sample, and the mixture was allowed to stand at room temperature for 24 hours.
Process between . From the main chain,

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0050

[Correction method] Change

[Correction content]

HO-Ar₁-OH, nC ₃ H ₇  -NH-CO-Ar₂-CO-NH-nC₃
H₇, HO-Ar₃-CO-NH-nC₃H₇

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Kamata 1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd. (72) Inventor Kiyoji Yoshida 370 Enzo, Chigasaki-shi, Kanagawa Mitsubishi Kasei Corporation Company Chigasaki Plant (72) Inventor Toshiyuki Hamano 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Chemical Co., Ltd. Yokkaichi Plant

Claims (3)

[Claims] 1. A structural unit represented by the following chemical formulas (1) to (5), the molar numbers of which are [1] to
When represented by [5], the molar fraction of each structural unit satisfies the following mathematical formulas (I) to (VI), and the terminal group is mainly composed of CH ₃ COO-group and -COOH group, and The terminal group concentrations are [CH ₃ COO-] and [-COO], respectively.
H], the following (VII) to (VII
A liquid crystalline polyester which satisfies the formula I) and has a melt viscosity of 30 poise or more measured at a temperature of 320 ° C. and a shear rate of 1000 sec ⁻¹ . [Chemical 1] [Equation 1] 2. An injection-molded article obtained by injection-molding the liquid crystalline polyester according to claim 1. 3. A component for electric / electronic materials, which uses the liquid crystalline polyester according to claim 1.