TWI721219B - Composite resin composition and connector formed by the composite resin composition - Google Patents

Abstract

The present invention provides a composite resin composition that can achieve the production of a connector that is excellent in heat resistance while suppressing warpage deformation and blistering, and has good fluidity, and a connector molded from the composite resin composition.

The composite resin composition of the present invention comprises: (A) a liquid crystal polymer; (B) a fibrous filler; and (C) a composite resin composition of a plate-shaped filler, the above-mentioned (A) liquid crystal polymer, A wholly aromatic polyamide ester that exhibits optical anisotropy when melted, and the weight average fiber of the above-mentioned (B) fibrous filler, which is composed of the following predetermined quantitative constituent units (I)-(VI) as essential constituent components The length is less than 200μm:

Description

Composite resin composition and connector formed by the composite resin composition

The present invention relates to a composite resin composition and a connector molded from the composite resin composition.

Liquid crystalline polymer is a thermoplastic resin with excellent dimensional accuracy and fluidity. Because of these characteristics, liquid crystalline polymers have been used as materials for various electronic components before.

In particular, with the miniaturization and thinning of electronic devices in recent years, there is a demand for low profile and narrow pitch of electronic components (connectors, etc.) constituting the electronic devices. For example, Patent Document 1 discloses a connector that is molded with a liquid crystalline polymer composition reinforced with mica and glass fibers. Such connectors are used as substrate-to-board connectors that require heat resistance, suppression of warpage, fluidity, dimensional stability, etc., or with flexible printed circuit boards (FPC), flexible flat cables ( FFC) connector for flexible printed circuit board connection.

[Advanced Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Application Publication No. 2006-37061

However, using the conventional liquid crystal polymer composition to form a connector, the composition’s heat resistance, suppression of warpage deformation, and fluidity are insufficient, and processability is poor, so it is difficult to produce a corresponding low profile and narrow pitch Low-profile and narrow-pitch connectors for the needs of the market.

In addition, in the liquid crystal polymer composition, the problem of foaming may occur. That is, because the liquid crystalline polyurethane of the liquid crystalline polymer has good thermal stability at high temperatures, it is often used in materials that require heat treatment at high temperatures. However, if the molded product is placed in high-temperature air or liquid for a long time, a problem of fine swelling called blistering will occur on the surface. This phenomenon is caused by the decomposition gas generated when the liquid crystalline polyamide is in the molten state being taken into the molded product. After that, the gas expands during high-temperature heat treatment and pushes out the surface of the molded product that has been softened by heating. The part appears as blisters. The occurrence of blistering can be reduced by fully degassing from the vent during the melt extrusion of the material, or by not staying in the molding machine for a long time during molding. However, the range of conditions is very narrow, and it is impossible to sufficiently obtain a molded product that suppresses the occurrence of blistering, that is, a molded product having blistering resistance. In order to fundamentally solve the problem of blistering, it is necessary to improve the quality of the liquid crystal polyamide itself. The conventional liquid crystal polyamide and the methods of using the same cannot fully solve the problem of blistering.

The present invention has been completed in view of these circumstances to provide a composite resin composition that can achieve excellent heat resistance while suppressing warpage deformation and blistering, a composite resin composition with good fluidity, and molding of the composite resin composition The connector is the target.

The inventors of the present invention have found that by combining a predetermined amount of a liquid crystal polymer, a fibrous filler, and a plate-like filler in a specific structural unit, the weight-average fiber length of the fibrous filler is 200 μm or less, which can solve the above problem. Subject. Specifically, the present invention provides the following.

(1) A composite resin composition comprising: (A) a liquid crystalline polymer; (B) a fibrous filler; and (C) a platy filler. The above (A) liquid crystalline polymer has only the following constituent units (I)-(VI), as essential constituents: the content of the constituent unit (I) to the total constituent unit is 50 to 70 mol%, and the content of the constituent unit (II) to the total constituent unit is 0.5 or more but less than 4.5 mol%, the content of the constituent unit (III) to the total constituent unit is 10.25-22.25 mol%, and the content of the constituent unit (IV) to the total constituent unit is 0.5 or more but less than 4.5 mol%, the constituent unit (V) The content of the total constituent unit is 5.75~23.75 mol%, the content of the constituent unit (VI) to the total constituent unit is 1~7 mol%, the total of the constituent unit (II) and the constituent unit (IV) is the total constituent unit The content of 1 mol or more but less than 5 mol%, the total content of constituent units (I) ~ (VI) to all constituent units is 100 mol%, constituent unit (VI) to constituent unit (V) and constituent unit (VI) The total molar ratio of (VI) is 0.04 to 0.37, and it shows optical anisotropy when melted. The weight average fiber length of the above (B) fibrous filler is 200 μm or less, and the above (A) ) Liquid crystalline polymer, 35 to 82.5 mass% for the entire composite resin composition, the above (B) fibrous filler, 1.5 to 17.5 mass% for the entire composite resin composition, the above (C) plate-shaped filler, The total amount of the above-mentioned (B) fibrous filler and the above-mentioned (C) platy filler is 17.5-65% by mass for the entire composite resin composition.

(2) The composite resin composition according to (1), wherein the total molar number of the structural unit (III) and the structural unit (IV) is the sum of the molar number of the structural unit (V) and the structural unit (VI) 1 to 1.1 times or 1 to 1.1 times the total molar number of the constituent unit (V) and the constituent unit (VI) of the total molar number of the constituent unit (III) and the constituent unit (IV).

(3) The composite resin composition according to (1) or (2), wherein the (B) fibrous filler is a ground fiber.

(4) The composite resin composition according to any one of (1) to (3), wherein one or more types are selected from the group consisting of (C) platy filler-based talc and mica.

(5) A connector formed of the composite resin composition described in any one of (1) to (4), and the product has a total length of less than 30 mm and a product height of less than 5 mm.

(6) The connector described in (5), which is a short-type narrow-pitch connector.

(7) The connector as described in (5) or (6), the distance between the intervals is 0.5mm or less, the total length of the product is 3.5mm or more, the height of the product is 4.0mm or less, and the board-to-board connector or flexible Low-profile narrow-pitch connectors for connectors for printed circuit boards.

According to the present invention, it is possible to provide a composite resin composition having excellent fluidity, and a connector molded from the composite resin composition, which can realize the manufacture of a connector having excellent heat resistance while suppressing warpage deformation and blistering.

Fig. 1 is a diagram showing the FPC connector formed in the embodiment. In addition, the unit of the numerical value in the figure is mm.

Fig. 2 is a diagram showing the measurement locations of the warpage measurement of the FPC connector performed in the examples.

Hereinafter, the embodiments of the present invention will be described in detail.

[Composite resin composition]

The composite resin composition of the present invention contains a predetermined amount of a liquid crystal polymer, a fibrous filler, and a plate-shaped filler, and the weight-average fiber length of the fibrous filler is 200 μm or less. Hereinafter, the components constituting the composite resin composition of the present invention will be described.

(Liquid crystal polymer)

The composite resin composition of the aspect of the present invention contains the above-mentioned wholly aromatic polyamide liquid crystal polymer. The above-mentioned wholly aromatic polyamide ester has a low melting point, so that the processing temperature can be lowered and the generation of decomposition gas during melting can be suppressed. As a result, a molded article obtained by molding a composite resin composition containing the above-mentioned wholly aromatic polyurethane can suppress blistering and improve blistering resistance. The liquid crystalline polymer can be used singly or in combination of two or more kinds.

The wholly aromatic polyamide ester of the present invention consists only of the following structural unit (I), the following structural unit (II), the following structural unit (III), the following structural unit (IV), and the following structural unit (V), and, and the following constituent unit (VI) composition.

[化2]

The constituent unit (I) is derived from 4-hydroxybenzoic acid (hereinafter, also referred to as "HBA"). The wholly aromatic polyamide of the present invention contains 50 to 70 mole% of the constituent unit (I) with respect to the total constituent unit. If the content of the constituent unit (I) is less than 50 mol%, or more than 70 mol%, at least one of melting point lowering and heat resistance tends to become insufficient. From the viewpoint of the coexistence of low melting point and heat resistance, the content of the constituent unit (I) is preferably 54-67 mol%, and more preferably 58-64 mol%.

The structural unit (II) is derived from 6-hydroxy-2-naphthoic acid (hereinafter also referred to as "HNA"). The wholly aromatic polyamide ester of the present invention contains 0.5 mol% or more but less than 4.5 mol% of the constituent unit (II) with respect to the total constituent unit. If the content of the constituent unit (II) is less than 0.5 mol%, or 4.5 mol% or more, at least one of melting point lowering and heat resistance tends to become insufficient. From the viewpoint of coexistence of low melting point and heat resistance, the content of constituent unit (II) is preferably 0.75 to 3.75 mol%, and more preferably 1 to 3 mol%.

The structural unit (III) is derived from 1,4-phenylene dicarboxylic acid (hereinafter, also referred to as "TA"). The wholly aromatic polyamide of the present invention contains 10.25 to 22.25 mole% of the constituent unit (III) with respect to the total constituent unit. If the content of the constituent unit (III) is less than 10.25 mol%, or exceeds 22.25 mol%, at least one of low melting point and heat resistance tends to become insufficient. From the viewpoint of coexistence of low melting point and heat resistance, the content of constituent unit (III) is preferably 12.963-20.75 mol%, and more preferably 15.675-19.25 mol%.

The constituent unit (IV) is derived from 1,3-phenylene dicarboxylic acid (hereinafter, also referred to as "IA"). The wholly aromatic polyamide of the present invention contains 0.5 mol% or more but less than 4.5 mol% constituent unit (IV) with respect to all constituent units. If the content of the constituent unit (IV) is less than 0.5 mol%, or 4.5 mol% or more, at least one of melting point reduction and heat resistance tends to become insufficient. From the viewpoint of coexistence of low melting point and heat resistance, the content of the constituent unit (IV) is preferably 0.5 to 3.75 mol%, and more preferably 0.5 to 3 mol%.

The constituent unit (V) is derived from 4,4'-dihydroxybiphenyl (hereinafter, also referred to as "BP"). The wholly aromatic polyamide ester of the present invention contains 5.75 to 23.75 mole% constituent unit (V) with respect to all constituent units. If the content of the constituent unit (V) is less than 5.75 mol%, or exceeds 23.75 mol%, at least one of lower melting point and heat resistance tends to become insufficient. From the viewpoint of coexistence of low melting point and heat resistance, the content of the constituent unit (V) is preferably 8.5-20.375 mol%, and more preferably 11.25-17 mol% (for example, 11.675-17 mol%).

The constituent unit (VI) is derived from N-acetyl-p-aminophenol (hereinafter, also referred to as "APAP"). The wholly aromatic polyamide ester of the present invention contains 1 to 7 mole% of the constituent unit (VI) with respect to the total constituent unit. If the content of the constituent unit (VI) is less than 1 mol%, or more than 7 mol%, at least one of a lower melting point and heat resistance tends to become insufficient. From the viewpoint of coexistence of low melting point and heat resistance, the content of the constituent unit (VI) is preferably 1.5-7 mol, and more preferably 2-7 mol%.

In the wholly aromatic polyamide ester of the present invention, the total of the structural unit (II) and the structural unit (IV) contains 1 mol% or more but less than 5 mol% with respect to the total structural unit. In the above-mentioned wholly aromatic polyamide, it is easy to coexist in the total amount of the above-mentioned range of the bendable structural unit (II) having a naphthalene skeleton and the bendable structural unit (IV) having a benzene skeleton. Make the low melting point and heat resistance fully coexist. The above-mentioned total content is less than 1 mol%, the ratio of the structural unit of the bendability becomes too small, and the melting point tends to be insufficient. If the above-mentioned total content is 5 mol% or more, the ratio of the structural unit of the bendability becomes too large, and the heat resistance tends to become insufficient. From the viewpoint of coexistence of low melting point and heat resistance, the total content is preferably 1.75 to 4.75 mol%, and more preferably 2.5 to 4.5 mol%.

In the wholly aromatic polyamide of the present invention, the total of the structural unit (V) and the structural unit (VI) has a molar ratio to the structural unit (VI) of 0.04 to 0.37. If the molar ratio is 0.04 or less, the ratio of the constituent units of the biphenyl skeleton will increase, and the crystallinity of the wholly aromatic polyamide will decrease, making it difficult to achieve a low melting point and sufficient heat resistance. In addition, if the molar ratio exceeds 0.37, heterogeneous bonds other than ester bonds will increase, and the crystallinity of the wholly aromatic polyamide ester will decrease, making it difficult to achieve a low melting point and sufficient heat resistance. From the viewpoint of coexistence of low melting point and heat resistance, the above-mentioned molar ratio is preferably 0.07 to 0.36, and more preferably 0.11 to 0.35.

From the viewpoint of the coexistence of low melting point and heat resistance, the total number of moles of the constituent unit (III) and the constituent unit (IV) (hereinafter also referred to as "mole number 1A") is based on the constituent unit (V) and composition The total number of moles of the unit (VI) (hereinafter, also referred to as "the number of moles 2A") is 1 to 1.1 times or the total number of moles of the constituent unit (V) and the constituent unit (VI), as the constituent unit ( III) 1 to 1.1 times the total molar number of the constituent unit (IV) is preferable. The molar number 1A is preferably 1.02~1.06 times the molar number 2A or the molar number 2A is 1.02~1.06 times the molar number 1A. The molar number 1A is preferably 1.024~1.056 times the molar number 2A or the molar number 2A is 1.024~1.056 times the molar number 1A.

As described above, in the wholly aromatic polyamide of the present invention, the specific structural unit (I) to (VI) and the total of the structural unit (II) and the structural unit (IV) are respectively compared to all the structural units. A specific amount is contained, and the molar ratio of the constituent unit (VI) to the total of the constituent unit (V) and the constituent unit (VI) is in a specific range, so that low melting point and heat resistance can sufficiently coexist. In addition, the wholly aromatic polyurethane of the present invention contains 100 mol% in the total of structural units (I) to (VI) with respect to all structural units.

As an index showing the above-mentioned heat resistance, a load deflection temperature (hereinafter, also referred to as "DTUL") can be used. If DTUL is above 260°C, the heat resistance tends to become higher, which is better. DTUL is obtained by melting and kneading 60% by mass of the above-mentioned wholly aromatic polyamide, 40% by mass of abrasive fibers with an average fiber diameter of 11 μm and an average fiber length of 75 μm, at the melting point of the above-mentioned wholly aromatic polyamide + 20°C. The value measured in the state of the obtained polyurethane resin composition can be measured in accordance with ISO75-1,2. From the viewpoint of the coexistence of low melting point and heat resistance, DTUL is preferably 265°C or more and 310°C or less, and more preferably 267~300°C.

Next, the method for producing the wholly aromatic polyamide of the present invention will be explained. In the wholly aromatic polyamide ester of the present invention, a direct polymerization method or a transesterification method is used for polymerization. During polymerization, melt polymerization, solution polymerization, slurry polymerization, solid phase polymerization, etc., or a combination of two or more of these can be used. Melt polymerization, or melt polymerization and solid phase polymerization can be used well. Combination of law.

In the present invention, at the time of polymerization, an acylating agent for polymerized monomers or a monomer that is terminally active as an acid chloride derivative can be used. Examples of the acylating agent include fatty acid anhydrides such as anhydrous acetic acid.

During the polymerization, various catalysts can be used. Representative examples include dialkyl tin oxides, diaryl tin oxides, titanium dioxide, alkoxy titanium silicates, and titanate alkyl esters. , Fatty acid metal salts, _{Lewis acid salts such as BF 3} , etc., preferably fatty acid metal salts. The amount of catalyst used is generally about 0.001 to 1% by mass based on the total mass of the monomer, and preferably about 0.003 to 0.2% by mass.

In addition, in solution polymerization or slurry polymerization, fluidized paraffin, highly heat-resistant synthetic oil, inert mineral oil, etc. are used as a solvent.

The reaction conditions are, for example, a reaction temperature of 200 to 380°C and a final pressure of 0.1 to 760 Torr (that is, 13 to 101,080 Pa). Especially in the melting reaction, for example, the reaction temperature is 260~380℃, preferably 300~360℃, the final pressure is 1~100 Torr (that is, 133~13,300Pa), and the temperature is 1~50 Torr (that is, 133~6,670Pa). ).

For the reaction, you can put all the raw material monomers (only HBA, HNA, TA, IA, BP, and APAP), the oxidizer, and the catalyst into the same reaction vessel to start the reaction (one-stage mode), or the raw materials The hydroxyl groups of HBA, HNA, BP, and APAP are acylated with an acylating agent, and then react with the carboxyl groups of TA and IA (two-stage mode).

Melt polymerization is performed after the temperature in the reaction system reaches a predetermined temperature, and then the pressure is reduced at a predetermined degree of pressure reduction. After the torque of the agitator reaches a predetermined value, an inert gas is introduced, and the pressure is passed from a decompressed state to a normal pressure to a predetermined pressurized state, and the wholly aromatic polyamide ester is discharged from the reaction system.

The wholly aromatic polyurethane produced by the above-mentioned polymerization method can be further subjected to solid-phase polymerization by heating in an inert gas under normal pressure or reduced pressure to increase the molecular weight. The preferable conditions for the solid-phase polymerization reaction are the reaction temperature of 230-350°C, preferably 260-330°C, and the final pressure is 10 to 760 Torr (ie, 1,330 to 101,080 Pa).

In the production method of the wholly aromatic polyamide ester of the present invention, 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 4,4'-dihydroxybiphenyl are contained in the presence of fatty acid metal salt. , And N-acetyl-p-aminophenol, acylated with fatty acid anhydride, and the step of transesterification with 1,4-phenylene dicarboxylic acid and 1,3-phenylene dicarboxylic acid is preferred. 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 1,4-phenylene dicarboxylic acid, 1,3-phenylene dicarboxylic acid, 4,4'-dihydroxybiphenyl, and N- A total monomer composed of acetaminophen and 4-hydroxybenzoic acid is used in an amount of 50-70 mol%. From the viewpoint of coexistence of low melting point and heat resistance, 54-67 mol% is preferred. 58~64 mol% is better; the usage amount of 6-hydroxy-2-naphthoic acid is 0.5 mol% or more but less than 4.5 mol%. From the viewpoint of coexistence of low melting point and heat resistance, 0.75~3.75 mol% Ear% is better, 1~3 mol% is more preferable; 1,4-phenylenedicarboxylic acid is used in an amount of 10.25-22.25 mol%. From the viewpoint of coexistence of low melting point and heat resistance, 12.963~ 20.75 mol% is better, and 15.675~19.25 mol% is more preferable; 1,3-phenylene dicarboxylic acid is used in an amount of 0.5 mol% or more but less than 4.5 mol%, resulting from lower melting point and heat resistance From the viewpoint of coexistence, 0.5~3.75 mol% is better, and 0.5~3% is more preferable; the usage amount of 4,4'-dihydroxybiphenyl is 5.75~23.75 mol%, which coexists with low melting point and heat resistance The point of view, 8.5-20.375 mol% is better, 11.25-17 mol% (e.g. 11.675-17 mol%) is even better; the usage amount of N-acetyl-p-aminophenol is 1-7 mol% %, from the viewpoint of low melting point and heat resistance coexisting, 1.5-7 mol% is preferred, and 2-7 mol% is more preferred; 6-hydroxy-2-naphthoic acid and 1,3-phenylene bis The total amount of carboxylic acid used is more than 1 mol% but less than 5 mol%. From the viewpoint of coexistence of low melting point and heat resistance, 1.75-4.75 mol% is preferred, and 2.5-4.5 mol% is more preferred; 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 1,4-phenylene dicarboxylic acid, 1,3-phenylene dicarboxylic acid, 4,4'-dihydroxybiphenyl, and N- The total usage amount of acetyl-p-aminophenol is preferably 100 mol%; the usage amount of N-acetyl-p-aminophenol is for 4,4'-dihydroxybiphenyl and N-acetyl-p-amine The molar ratio of the total amount of base phenol used is 0.04~0.37. From the viewpoint of coexistence of low melting point and heat resistance, 0.07~0.36 is preferred, and 0.11~0.35 is more preferred. The usage amount of the above fatty acid anhydride is 4 It is preferable that the total hydroxyl equivalent of hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 4,4'-dihydroxybiphenyl, and N-acetyl-p-aminophenol is 1.02 to 1.04 times. The fatty acid metal salt is an acetic acid metal salt, and the fatty acid anhydride is preferably anhydrous acetic acid. In addition, the total molar number of 1,4-phenylene dicarboxylic acid and 1,3-phenylene dicarboxylic acid (hereinafter, also referred to as "mole number 1B") is calculated as 4,4'-bis The total molar number of hydroxybiphenyl and N-acetyl-p-aminophenol (hereinafter also referred to as "mole number 2B") is 1 to 1.1 times, or 4,4'-dihydroxybiphenyl and N -The total number of moles of acetoxy-p-aminophenol is preferably 1 to 1.1 times the total number of moles of 1,4-phenylene dicarboxylic acid and 1,3-phenylene dicarboxylic acid. The molar number 1B is 1.02~1.06 times the molar number 2B, or the molar number 2 is 1.02~1.06 times the molar number 1B. The molar number 1B is 1.024~1.056 times the molar number 2B, or the molar number 2B is 1.024~1.056 times the molar number 1B.

Next, the properties of the wholly aromatic polyamide will be explained. The wholly aromatic polyamide ester of the present invention exhibits optical anisotropy when melted. It exhibits optical anisotropy when melted, and represents the wholly aromatic polyamide ester-based liquid crystal polymer of the present invention.

In the present invention, the wholly aromatic polyamide is a liquid crystalline polymer, which is an indispensable element for the wholly aromatic polyamide to have both thermal stability and ease of processing. The wholly aromatic polyamides composed of the above-mentioned structural units (I) to (VI) may not form an anisotropic melt phase depending on the composition and sequence distribution in the polymer. However, the polymer of the present invention Limited to wholly aromatic polyamide esters that exhibit optical anisotropy when melted.

The properties of melting anisotropy can be confirmed by a conventional polarization inspection method using crossed polarizers. More specifically, the confirmation of the melting anisotropy was carried out by using a polarizing microscope manufactured by Olympus Corporation, melting the sample placed on a heating stage manufactured by LINKAM Corporation, and observing at a magnification of 150 times in a nitrogen atmosphere. Liquid crystalline polymers are optically anisotropic, and when inserted between crossed polarizers, light can penetrate. If the sample is optically anisotropic, for example, even in a molten static liquid state, polarized light can be transmitted.

Nematic liquid crystalline polymers have a significant decrease in viscosity above the melting point. Therefore, liquid crystallinity is generally displayed at a temperature above the melting point and becomes an index of processability. The melting point is preferably as high as possible from the viewpoint of heat resistance. However, in consideration of thermal deterioration during polymer melt processing and the heating capacity of the molding machine, it is better to aim at 360°C or less. Furthermore, 300~360°C is preferred, and 340~358°C is even more preferred.

It is better to use a temperature 10-30°C higher than the melting point of the wholly aromatic polyamide of the present invention and a shear speed of 1000/sec. The melt viscosity of the above-mentioned wholly aromatic polyamide is 500 Pa‧s or less. 0.5~300Pa‧s is better, and 1~100Pa‧s is more preferable. When the melt viscosity is within the above range, the wholly aromatic polyamide itself or the composition containing the wholly aromatic polyamide can easily ensure fluidity during molding, and the filling pressure will not easily become excessive. . In addition, in this specification, the so-called melt viscosity refers to the melt viscosity measured in compliance with ISO11443.

As an index showing the above-mentioned heat resistance, the difference between the melting point and DTUL can be cited. If this difference is below 90°C, the heat resistance tends to increase, which is preferable. From the viewpoint of coexistence of low melting point and heat resistance, the above-mentioned difference is preferably more than 0°C and less than 85°C (for example, 50°C or more and 85°C or less), and more preferably 55 to 79°C.

In the composite resin composition of the present invention, the above-mentioned liquid crystalline polymer is contained in the composite resin composition at 35 to 82.5% by mass with respect to the entire composite resin composition. If the content of the liquid crystalline polymer is less than 35% by mass based on the total composite resin composition, the fluidity of the composite resin composition tends to deteriorate. In addition, due to warpage of molded products such as connectors obtained from the composite resin composition Deformation may become larger and unfavorable. If the content of the liquid crystalline polymer exceeds 82.5% by mass of the entire composite resin composition, the flexural modulus of elasticity and crack resistance of molded products such as connectors obtained from the composite resin composition will decrease and become unsatisfactory. In the composite resin composition of the present invention, the above-mentioned liquid crystal polymer is preferably contained in the composite resin composition at 47 to 75% by mass, and more preferably 60 to 65% by mass in the entire composite resin composition.

(Fibrous filler)

The composite resin composition of the present invention contains the above-mentioned liquid crystal polymer and a fibrous filler. Since the weight average fiber length of the fibrous filler is 200 μm or less, the molded product obtained by molding the composite resin composition has a high temperature Excellent rigidity and fluidity, while suppressing warpage and deformation. The fibrous filler can be used singly or in combination of two or more kinds. The fibrous filler of the present invention is not particularly limited, and examples include glass fiber, abrasive fiber, carbon fiber, asbestos fiber, silica fiber, and silica. Alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, etc. Since it is easy to increase the high-temperature rigidity of the molded article obtained from the composite resin composition, the fibrous filler of the present invention is preferably glass fiber.

In the composite resin composition of the present invention, the weight average fiber length of the fibrous filler is 200 μm or less, preferably 170 μm or less, and more preferably 150 μm or less. If the weight average fiber length exceeds 200 μm, the fluidity obtained from the composite resin composition is not likely to become sufficient, and the warpage deformation of the molded article may become large, which is unfavorable. The lower limit of the weight average fiber length is not particularly limited, but is preferably 50 μm or more, and more preferably 70 μm or more. If the weight average fiber length is 50 μm or more, the high-temperature rigidity of the molded article obtained from the composite resin composition is likely to be sufficient and preferable. In addition, in this specification, the weight average fiber length of the fibrous filler means that the composite resin composition is heated and ashed at 600°C for 2 hours to obtain an ashing residue, and the ashing residue is dispersed in 5% by mass. The polyglycol aqueous solution was used to obtain a dispersion, and the weight average fiber length was measured using a video measuring device for the dispersion.

In addition, the fiber diameter of the fibrous filler of the present invention is not particularly limited, but a fiber diameter of about 5 to 15 μm is generally used.

In the composite resin composition of the present invention, the composite resin composition contains 1.5 to 17.5% by mass of the fibrous filler with respect to the entire composite resin composition. If the content of the fibrous filler is less than 1.5% by mass based on the total composite resin composition, molded products such as connectors obtained from the composite resin composition will have a low load deflection temperature and insufficient high-temperature rigidity. . When the content of the fibrous filler exceeds 17.5% by mass based on the entire composite resin composition, the fluidity of the composite resin composition will deteriorate, and the warpage of the molded product may become large, which is undesirable. In the fibrous filler of the present invention, the composite resin composition preferably contains 4 to 16% by mass, and more preferably 5 to 15% by mass in the entire composite resin composition.

(Plate filler)

The composite resin composition of the present invention further contains a plate-shaped filler. By including the plate-shaped filler in the composite resin composition of the present invention, a molded product with suppressed warpage can be obtained. The plate-shaped filler can be used singly or in combination of two or more kinds.

The plate-shaped filler contains 12.5 to 47.5% by mass with respect to the entire composite resin composition. If the content of the plate-shaped filler is less than 12.5% by mass based on the entire composite resin composition, it is not preferable because the warpage deformation of the molded article obtained from the composite resin composition cannot be sufficiently suppressed. If the content of the plate-like filler exceeds 47.5 mass% in the total composite resin composition, the fluidity of the composite resin composition will deteriorate, and the molding of the composite resin composition may become difficult, which is undesirable. In the slab filler of the present invention, the composite resin composition preferably contains 20 to 37% by mass, and more preferably 25 to 35% by mass of the entire composite resin composition.

The plate-like filler of the present invention includes talc, mica, glass flakes, various metal foils, etc., which does not deteriorate the fluidity of the composite resin composition and can suppress the warpage of the molded article obtained from the composite resin composition. The point of deformation is preferably at least one selected from talc and mica, and mica is more preferred. In addition, the average particle size of the plate-shaped filler is not particularly limited, but considering the fluidity in the shallow wall portion, it is better to be smaller. On the other hand, in order to reduce the warpage deformation of molded products such as connectors obtained from the composite resin composition, it is necessary to maintain a certain size. Specifically, 1~100μm is preferred, and 5~50μm is more preferred.

[Talc]

The talc that can be used in the present invention is such that the total solid content of the talc, _{the total content of Fe 2} O ₃ , Al ₂ O ₃ and CaO is 2.5% by mass or less, and the total content of Fe ₂ O ₃ and Al ₂ O ₃ It is more than 1.0% by mass, 2.0% by mass or less, and the content of CaO is preferably less than 0.5% by mass. That is, the talc that can be used in the present invention may _{contain at least one of Fe 2} O ₃ , Al ₂ O _{3 and CaO in addition to the main components of SiO 2} and MgO, and each component may be within the above-mentioned content range. contain.

In the above talc, _{the total content of Fe 2} O ₃ , Al ₂ O ₃ and CaO is 2.5% by mass or less, the molding processability of the composite resin composition and the heat resistance of molded products such as connectors formed from the composite resin composition Sex is not easy to deteriorate. The total content of Fe ₂ O ₃ , Al ₂ O ₃ and CaO is preferably 1.0% by mass or more, and 2.0% by mass or less.

In addition, among the above-mentioned talc, talc _{whose total content of Fe 2} O ₃ and Al ₂ O ₃ exceeds 1.0 mass is easy to obtain. In addition, in the above-mentioned talc, _{the total content of Fe 2} O ₃ and Al ₂ O ₃ is 2.0% by mass or less, the molding processability of the composite resin composition and the heat resistance of molded products such as connectors molded from the composite resin composition Sex is not easy to deteriorate. The total content of Fe ₂ O ₃ and Al ₂ O ₃ is preferably more than 1.0% by mass, and preferably 1.7% by mass or less.

In addition, if the content of CaO in the talc is less than 0.5% by mass, the molding processability of the composite resin composition and the heat resistance of molded products such as connectors molded from the composite resin composition are unlikely to deteriorate. The content of CaO is preferably 0.01% by mass or more, and 0.4% by mass or less.

_{In the talc of the present invention, the cumulative average particle size (D 50} ) on a mass basis or a volume basis measured by a laser diffraction method is based on the viewpoint of preventing warpage and deformation of the molded product and maintaining the fluidity of the composite resin composition. 4.0~20.0μm is preferred, and 10~18μm is more preferred.

[Mica]

The so-called mica is a crushed product of silicate minerals containing aluminum, potassium, magnesium, sodium, and iron. The mica that can be used in the present invention includes muscovite, phlogopite, biotite, artificial mica, etc. Among them, muscovite is preferred because of its good color tone and low price.

In addition, in the production of mica and methods of pulverizing minerals, a wet pulverization method and a dry pulverization method are known. The so-called wet pulverization method is a method of coarsely pulverizing the raw mica with a dry pulverizer, adding water to make it into a slurry state, performing the main pulverization by wet pulverization, and then dehydrating and drying. Compared with the wet pulverization method, the dry pulverization method is a low-cost and general method, but the wet pulverization method is easier to pulverize the fine minerals. For the reason that mica with a preferable average particle diameter and thickness described later can be obtained, it is preferable to use a finely pulverized product in the present invention. Therefore, in the present invention, it is preferable to use mica produced by a wet pulverization method.

In addition, in the wet pulverization method, since a step of dispersing the pulverized material in water is required, in order to improve the dispersion efficiency of the pulverized material, a coacervation settling agent and/or a sedimentation aid is generally added to the pulverized material. The flocculation and sedimentation aids that can be used in the present invention include polyaluminum chloride, aluminum sulfate, ferrous sulfate, ferric sulfate, cuprous chloride, polyferric sulfate, polyferric chloride, iron-silicon dioxide Inorganic polymer flocculant, iron chloride-silica inorganic polymer flocculant, slaked lime (Ca(OH) ₂ ), caustic soda (NaOH), limestone (Na ₂ CO ₃ ), etc. These coagulation and sedimentation agents and sedimentation aids have alkaline or acidic pH. The mica used in the present invention preferably does not use a cohesive sedimentation agent and/or sedimentation aid during wet pulverization. Without the use of mica treated with coagulation and/or sedimentation aids, the polymer in the composite resin composition is not easily decomposed, and it is not easy to cause a large amount of gas or reduce the molecular weight of the polymer, so it can be easily and better. Maintain the performance of molded products such as the resulting connector.

The mica that can be used in the present invention has an average particle size measured by the Microtrac laser diffraction method, preferably 10-100 μm, and particularly preferably an average particle diameter of 20-80 μm. The average particle size of mica is 10 μm or more, and the effect of improving the rigidity of the molded product becomes easy and sufficient. If the average particle size of mica is less than 100 μm, the rigidity of the molded product can be improved easily, and the clamping strength can be easily improved. Furthermore, if the average particle size of mica is 100 μm or less, it is easy to ensure fluidity for molding the connector of the present invention.

The thickness of the mica that can be used in the present invention, as measured by electron microscope observation, is preferably 0.01 to 1 μm, and particularly preferably 0.03 to 0.3 μm. The thickness of the mica is 0.01 μm or more. Since the mica is not easily cracked during the melt processing of the composite resin composition, it is preferable that the rigidity of the molded product is easily increased. The thickness of mica is 1 µm or less, and the effect of improving the rigidity of the molded product becomes easy and sufficient.

The mica that can be used in the present invention can also be surface treated with a silane coupling agent, and/or, can also be granulated into granules with a binder.

In the composite resin composition of the present invention, the total amount of the fibrous filler and the plate-shaped filler is 17.5 to 65% by mass with respect to the entire composite resin composition. If the total amount mentioned above is less than 17.5% by mass based on the total composite resin composition, molded products such as connectors obtained from the composite resin composition will have a low load deflection temperature and insufficient high-temperature rigidity. In addition, warpage may occur. The risk of becoming bigger is not good. If the above-mentioned total amount exceeds 65% by mass of the entire composite resin composition, the fluidity of the composite resin composition will deteriorate, and the warpage deformation of the molded product may increase, which is not preferable. The above-mentioned total amount is preferably 25 to 53% by mass, more preferably 35 to 40% by mass of the entire composite resin composition.

(Other ingredients)

In the composite resin composition of the present invention, in addition to the above-mentioned components, pigments such as nucleating agents, carbon black, inorganic calcined pigments, oxidation inhibitors, stabilizers, plasticizers, lubricants, mold release agents, Flame retardant, and one or more of conventional inorganic fillers.

The method for producing the composite resin composition of the present invention is not particularly limited as long as the components in the composite resin composition can be uniformly mixed so that the weight average fiber length of the fibrous filler is 200 μm or less. The method of producing the resin composition is appropriately selected. For example, a method of using a melt-kneading device such as a uniaxial or twin-screw extruder to melt, knead and extrude each component, and then process the resulting composite resin composition into a desired form such as powder, chips, pellets, etc. .

In the composite resin composition of the present invention, due to its excellent fluidity, the minimum filling pressure during molding does not easily become excessive, and connectors can be molded well, especially for small and complex shapes such as short-shaped narrow-pitch connectors. Components and so on. The degree of fluidity is judged by the minimum filling pressure of the connector. That is, when the FPC connector shown in FIG. 1 is injection molded, the minimum injection filling pressure at which a good molded product can be obtained is specified as the minimum filling pressure. The lower the minimum filling pressure is, the better the fluidity is evaluated.

The melt viscosity of the composite resin composition measured in accordance with ISO11443 at a temperature 10~30°C higher than the melting point of the liquid crystal polymer at a shear rate of 1000/s, is ^{below 1×10 5} Pa‧s (at 5Pa‧s or more , 1×10 ² Pa‧s or less is better). When forming connectors, especially short-shaped narrow-pitch connectors, the fluidity of the composite resin composition can be ensured, and the filling pressure will not become excessive. good.

(Connector)

By molding the composite resin composition of the present invention, the connector of the present invention can be obtained. The connector of the present invention is not particularly limited. For example, a connector having a product length of less than 30 mm and a product height of less than 5 mm can be mentioned. Connectors with a product length of less than 30 mm and a product height of less than 5 mm are not particularly limited. Examples include low profile narrow pitch connectors, coaxial connectors, micro SIM connectors, and micro SD connectors. Among them, it is suitable for short-type narrow-pitch connectors. The low-profile narrow-pitch connectors are not particularly limited. Examples include board-to-board connectors (also known as "BtoB connectors"), flexible printed circuit board connectors (used to connect flexible printed circuit Board (FPC) and flexible flat cable (FFC), also known as "FPC connector") and so on. It is especially suitable for short-type narrow-pitch connectors for substrate-to-board connectors or flexible printed circuit board connectors with a distance between intervals of 0.5mm or less, a product length of 3.5mm or more, and a product height of 4.0mm or less.

The forming method for obtaining the connector of the present invention is not particularly limited. In order to prevent deformation of the obtained connector, etc., it is preferable to select forming conditions that do not have internal residual stress. The filling pressure is low to reduce the internal residual stress of the resulting connector. The temperature of the barrel of the molding machine is preferably a temperature higher than the melting point of the liquid crystal polymer.

In addition, the temperature of the metal mold is preferably 70~100°C. If the metal mold temperature is too low, it is likely to cause poor flow of the composite resin composition filled in the metal mold, which is unfavorable. If the temperature of the metal mold is too high, problems such as burrs may occur, which is not good. Regarding the injection speed, it is better to mold at 150 mm/sec or more. If the injection speed is too low, it is only possible to obtain unfilled molded products. Even if a completely filled molded product is obtained, it becomes a molded product with high filling pressure and large internal residual stress. However, there are some cases where only connectors with large warpage deformation can be obtained. possibility.

The connector of the present invention suppresses warpage and deformation. The degree of warpage of the connector is judged as follows. That is, the FPC connector shown in FIG. 1 is used to measure the heights of the plural positions shown by the black circles in FIG. 2, and the difference between the maximum height and the minimum height of the least square plane is used as warpage. The connector of the present invention suppresses warpage changes before and after IR reflow.

In addition, the connector of the present invention suppresses the occurrence of blistering. The degree of foaming can be judged by the foaming temperature. That is, by visual observation, the surface of the molded product was clamped for 5 minutes with a hot press at a predetermined temperature, and whether blistering occurred or not, and the highest temperature at which the number of blisters occurred was zero as the blistering temperature. The higher the bubbling temperature is, it is estimated that the occurrence of blistering is suppressed.

In addition, the connector obtained from the composite resin composition of the present invention has excellent heat resistance, for example, heat resistance evaluated by high-temperature rigidity. The high temperature rigidity is evaluated by measuring the deflection temperature under load in accordance with ISO75-1,2.

[Example]

Hereinafter, the present invention will be specifically described with examples, but the present invention is not limited to these.

<Synthesis Example 1>

Put the following raw material monomers, fatty acid metal salt catalysts, and acylating agents into a polymerization vessel equipped with a mixer, a return pipe, a monomer input port, a nitrogen introduction port, and a decompression/outflow line, and start nitrogen replacement.

(I) 4-Hydroxybenzoic acid 9.7 mol (58 mol%) (HBA)

(II) 6-hydroxy-2-naphthoic acid 0.17 mol (1 mol%) (HNA)

(III) Terephthalic acid 3.2 mol (19.25 mol%) (TA)

(IV) Isophthalic acid 0.25 mol (1.5 mol%) (IA)

(V) 4,4'-Dihydroxybiphenyl 2.5 mol (15.25 mol%) (BP)

(VI) N-Acetyl p-aminophenol 0.83 mol (5 mol%) (APAP)

Potassium acetate catalyst 110mg

Anhydrous acetic acid 1734g (1.03 times the total hydroxyl equivalent of HBA, HNA, BP, and APAP)

After putting in the raw materials, the temperature of the reaction system was raised to 140°C and reacted at 140°C for 1 hour. After that, the temperature was further increased to 360°C for 5.5 hours, and the pressure was reduced to 10 Torr (that is, 1330 Pa) in 20 minutes, and while acetic acid, excess anhydrous acetic acid, and other low-boiling components were distilled off, melt polymerization was performed. After the stirring torque reaches a predetermined value, nitrogen is introduced, and the reduced pressure is passed through normal pressure to a pressurized state, and the polymer is discharged from the lower part of the polymerization vessel.

<Assessment>

For the wholly aromatic polyamide of Synthesis Example 1, the melting point, melt viscosity, and DTUL were evaluated by the following methods. The evaluation results are shown in Table 1.

[Melting point]

After observing the endothermic peak temperature (Tm1) observed when measuring the polymer from room temperature at a temperature increase of 20°C/min by DSC (manufactured by TA Instrument), after keeping it at (Tm1+40)°C for 2 minutes Measure the temperature of the endothermic peak observed during the temperature rise condition of 20°C/min once it has been cooled to room temperature under the cooling condition of 20°C/min.

[DTUL]

60% by mass polymer and 40% by mass glass fiber (EFH75-01 manufactured by Central Glass Co., Ltd., milled fiber, average fiber diameter 11μm, average fiber length 75μm), using a twin-screw extruder ((stock) Japan Steel TEX30α type), melted and kneaded at the melting point of the polymer + 20°C of the barrel temperature to obtain pellets of the polyamide resin composition.

The pellets of the above-mentioned polyurethane resin composition were molded using a molding machine ("SE100DU" manufactured by Sumitomo Heavy Industries Co., Ltd.) under the following molding conditions to obtain a test piece for measurement (4 mm×10 mm×80 mm). Using this test piece, the deflection temperature under load was measured in accordance with the method of ISO75-1,2. Furthermore, 1.8 MPa is used for the torsion stress. The results are shown in Table 1.

[Forming conditions]

Material pipe temperature: melting point of polymer +15℃

Metal mold temperature: 80℃

Back pressure: 2MPa

Injection speed: 33mm/sec

[Melting viscosity]

Use a capillary rheometer manufactured by Toyo Seiki Co., Ltd., at a temperature 10~30°C higher than the melting point of liquid crystal polymer, use an orifice with an inner diameter of 1mm and a length of 20mm, and a shear speed of 1000/sec. ISO11443, measuring the melt viscosity of liquid crystalline polymers. In addition, the measured temperature is as described in Table 1.

<Synthesis Examples 2-18, Comparative Synthesis Examples 1-11>

Except for the types of raw material monomers and the charging ratio (mol %) shown in Tables 1 to 3, a polymer was obtained in the same manner as in Synthesis Example 1. In addition, the same evaluation as in Synthesis Example 1 was performed. The evaluation results are shown in Tables 1 to 3.

[Table 2]

<Examples 1 to 10, Comparative Examples 1 to 6>

In the following Examples and Comparative Examples, the liquid crystalline polymer 1 is the liquid crystalline polymer obtained in Synthesis Example 15. In addition, liquid crystal polymers 2 and 3 were manufactured as follows.

In addition, in this example, the melting point and melt viscosity of the pellets were measured under the following conditions, respectively.

[Determination of melting point]

After observing the endothermic peak temperature (Tm1) observed when measuring the liquid crystalline polymer from room temperature with a temperature rising condition of 20°C/min with a DSC manufactured by TA Instrument, the temperature was maintained at (Tm1+40)°C. After 2 minutes, once cooled to room temperature under the cooling condition of 20°C/min, the endothermic peak temperature observed during the measurement under the heating condition of 20°C/min was observed again.

[Determination of Melt Viscosity]

Use Capillary Rheometer Type 1B manufactured by Toyo Seiki Co., Ltd., at a temperature 10~30℃ higher than the melting point of liquid crystal polymer, use an orifice with an inner diameter of 1mm and a length of 20mm, at a shear speed of 1000/sec. , Comply with ISO11443, measure the melt viscosity of liquid crystal polymers. In addition, the temperature was measured, and the liquid crystal polymer 1 was 360°C, the liquid crystal polymer 2 was 350°C, and the liquid crystal polymer 3 was 380°C.

(Method of manufacturing liquid crystalline polymer 2)

In a polymerization vessel equipped with a mixer, a reflux tube, a monomer input port, a nitrogen introduction port, and a pressure reduction/outflow line, the following raw material monomers, metal catalysts, and acylating agents are placed, and nitrogen replacement is started.

(I) 4-Hydroxybenzoic acid: 1380g (60 mol%) (HBA)

(II) 6-Hydroxy-2-naphthoic acid: 157g (5 mol%) (HNA)

(III) Terephthalic acid: 484g (17.5 mol%) (TA)

(IV) 4,4'-Dihydroxybiphenyl: 388g (12.5 mol%) (BP)

(V) 4-Acetoxyaminophenol: 126g (5 mol%) (APAP)

Potassium acetate catalyst 110mg

Anhydrous acetic acid 1659g

After the raw materials were put into the polymerization vessel, the temperature of the reaction system was raised to 140°C, and the reaction was carried out at 140°C for 1 hour. After that, the temperature was increased to 340°C over a further 4.5 hours, and the pressure was reduced to 10 Torr (that is, 1330 Pa) over 15 minutes, while acetic acid, excess anhydrous acetic acid, and other low-boiling components were distilled off to perform melt polymerization. After the stirring torque reaches a predetermined value, nitrogen is introduced, the reduced pressure is passed through the normal pressure to make a pressurized state, the polymer is discharged from the lower part of the polymerization vessel, and the rubber strip is pelletized by a cutter. The obtained pellets have a melting point of 336°C and a melt viscosity of 19Pa‧s.

(Method for manufacturing liquid crystal polymer 3)

Put the following raw material monomers, fatty acid metal salt catalysts, and acylating agents into a polymerization vessel equipped with a mixer, a return pipe, a monomer input port, a nitrogen introduction port, and a decompression/outflow line, and start nitrogen replacement.

(I) 4-Hydroxybenzoic acid: 1040g (48 mol%) (HBA)

(II) 6-Hydroxy-2-naphthoic acid: 89g (3 mol%) (HNA)

(III) Terephthalic acid: 547g (21 mol%) (TA)

(IV) Isophthalic acid: 91g (3.5 mol%) (IA)

(V) 4,4'-Dihydroxybiphenyl: 716g (24.5 mol%) (BP)

Potassium acetate catalyst: 110mg

Anhydrous acetic acid: 1644g

After the raw materials were put into the polymerization vessel, the temperature of the reaction system was raised to 140°C, and the reaction was carried out at 140°C for 1 hour. After that, the temperature was increased to 360°C over a further 5.5 hours, and the pressure was reduced to 5 Torr (that is, 667 Pa) over 20 minutes, while acetic acid, excess anhydrous acetic acid, and other low-boiling components were distilled off to perform melt polymerization. After the stirring torque reaches a predetermined value, nitrogen is introduced, the reduced pressure is passed through the normal pressure to make a pressurized state, the polymer is discharged from the lower part of the polymerization vessel, and the rubber strip is pelletized by a cutter. The obtained pellets have a melting point of 355°C and a melt viscosity of 10Pa‧s.

(Ingredients other than liquid crystal polymer)

Using a biaxial extruder, each liquid crystalline polymer obtained above was mixed with the following components to obtain a composite resin composition. The blending amount of each component is shown in Table 4 and Table 5. In addition, in the following, "%" in the table indicates mass%.

(B) Fibrous filler

Glass fiber: ECS03T-786H manufactured by Nippon Electric Glass Co., Ltd., a cut strand with a fiber diameter of 10μm and a length of 3mm

Polished fiber: PF70E001 manufactured by Nittobo Co., Ltd., fiber diameter 10μm, average fiber length 70μm (manufacturer's nominal value)

In addition, the above-mentioned manufacturer's nominal value is different from 100 μm in Table 4 of the actual measured value in the composition.

(C) Plate filler

Talc: Made by Matsumura Industry Co., Ltd., CROWN TALC PP, with an average particle size of 10μm

Mica: AB-25S manufactured by Yamaguchi Mica Industry, with an average particle size of 25μm

In addition, the extrusion conditions when obtaining the composite resin composition are as follows.

[Extrusion conditions]

[Examples 1 to 10, Comparative Examples 1 to 3]

The temperature of the material tube set at the main feed port is 250°C, and the temperature of the other material tubes is 360°C. Liquid crystalline polymers are all supplied from the main feed port. In addition, the filler is supplied from the side supply port.

[Comparative Example 4]

The temperature of the material tube set at the main feed port is 250°C, and the temperature of the other material tubes is 350°C. Liquid crystalline polymers are all supplied from the main feed port. In addition, the filler is supplied from the side supply port.

[Comparative Example 5]

The temperature of the material tube set at the main feed port is 250°C, and the temperature of the other material tubes is 370°C. Liquid crystalline polymers are all supplied from the main feed port. In addition, the filler is supplied from the side supply port.

In addition, the weight average fiber length of the fibrous filler in the composite resin composition was measured by the following method.

[Measurement of weight average fiber length]

The pellets of 5 g of the composite resin composition were heated at 600° C. for 2 hours to ash. After the ashing residue was sufficiently dispersed in a 5 mass% polyethylene glycol aqueous solution, it was moved to a petri dish with a dropper, and the fibrous filler was observed under a microscope. At the same time, the weight-average fiber length of the fibrous filler was measured using a video measuring device (LUZEXFS manufactured by NIRECO).

(Measurement of melt viscosity of composite resin composition)

Use Capillary Rheometer Type 1B manufactured by Toyo Seiki Co., Ltd., at a temperature 10~30°C higher than the melting point of liquid crystal polymer, use an orifice with an inner diameter of 1mm and a length of 20mm, at a shear speed of 1000/sec. , Comply with ISO11443, measure the melt viscosity of the composite resin composition. In addition, the temperature was measured at 360°C for the composite resin composition system using the liquid crystal polymer 1, and 350°C for the composite resin composition system using the liquid crystal polymer 2, and the composite resin composition system using the liquid crystal polymer 3 380°C. The results are shown in Table 4 and Table 5.

Based on the following method, the physical properties of the connector molded from the composite resin composition were measured. The results of each evaluation are shown in Table 4 and Table 5.

(Bending test)

Under the following molding conditions, the composite resin composition was injection molded to obtain a 0.8 mm thick molded product, and the bending strength, breaking twist, and bending elastic modulus were measured in accordance with ASTM D790.

[Forming conditions]

Forming machine: Sumitomo Heavy Industries, SE100DU

Material pipe temperature:

360°C (Examples 1~10, Comparative Examples 1~3)

350°C (Comparative Example 4)

370°C (Comparative Examples 5 and 6)

Metal mold temperature: 80℃

Injection speed: 33mm/sec

(Deflection temperature under load)

Under the following molding conditions, the composite resin composition was injection molded to obtain a molded product, and the deflection temperature under load was measured in accordance with ISO75-1,2.

Forming machine: Sumitomo Heavy Industries, SE100DU

Material pipe temperature:

360°C (Examples 1~10, Comparative Examples 1~3)

350°C (Comparative Example 4)

370°C (Comparative Examples 5 and 6)

Metal mold temperature: 80℃

Injection speed: 33mm/sec

(Bubbling temperature)

The composite resin composition was injection molded under the following molding conditions to obtain a molded product of 12.5 mm×120 mm×0.8 mm with a clamping part. The molded product was divided into two pieces by the mold clamping part as a sample, and clamped by a hot press at a predetermined temperature for 5 minutes. After that, it was visually inspected whether blistering occurred on the surface of the specimen. The foaming temperature is the highest temperature at which the number of foaming is zero. Furthermore, the above-mentioned predetermined temperature is set in the range of 250 to 300°C at every 10°C interval.

[Forming conditions]

Forming machine: Sumitomo Heavy Industries, SE100DU

Material pipe temperature:

360°C (Examples 1~10, Comparative Examples 1~3)

350°C (Comparative Example 4)

370°C (Comparative Examples 5 and 6)

Metal mold temperature: 90℃

Injection speed: 33mm/sec

(Warpage of FPC connector)

The composite resin composition was injection molded under the following molding conditions (gate: tunnel gate, gate size: ψ 0.4mm), as shown in Figure 1, the overall size is 17.6mm×4.00mm×1.16mm , FPC connector with a distance of 0.5mm between intervals, 30×2 pin holes, and minimum wall thickness: 0.12mm.

[Forming conditions]

Forming machine: Sumitomo Heavy Industries SE30DUZ

Material pipe temperature (indicating the temperature from the nozzle side):

360℃-360℃-350℃-340℃ (Examples 1~10, Comparative Examples 1~3)

350℃-350℃-340℃-330℃ (Comparative Example 4)

370℃-370℃-360℃-350℃ (Comparative Examples 5 and 6)

Metal mold temperature: 80℃

Injection speed: 200mm/sec

Holding pressure: 50MPa

Holding time: 0.5 seconds

Cooling time: 10 seconds

Screw speed: 120rpm

Screw back pressure: 1.2MPa

The obtained connector was allowed to stand on a horizontal table, and the height of the connector was measured with a Quick Visioni 404PROCNC video measuring machine manufactured by Mtutoyo. At this time, the height was measured at a plurality of positions indicated by black circles in FIG. 2, and the difference between the maximum height and the minimum height of the least square plane was used as the warpage of the FPC connector. In addition, the warpage was measured before and after IR reflow under the following conditions.

[IR reflow conditions]

Measuring machine: Large-scale desktop reflow welding device RF-300 manufactured by Japan Pulse Technology Research Institute (using far-infrared heater)

Sample conveying speed: 140mm/sec

Reflow furnace passing time: 5 minutes

The temperature condition of the preheating zone: 150℃

Temperature condition of reflow zone: 190℃

Peak temperature: 251℃

(Deformation of FPC connector)

The warpage difference before and after reflow measured by the above method is used to obtain the deformation amount of the FPC connector.

(Minimum filling pressure of FPC connector)

When the FPC connector shown in Fig. 1 is injection molded, the minimum injection filling pressure at which a good molded product can be obtained is measured as the minimum filling pressure.

As shown in Tables 4 and 5, the composite resin composition of the present invention has excellent fluidity, and a connector molded from the composite resin composition has excellent heat resistance and suppresses the occurrence of warpage deformation and blistering.

Claims (7)

A composite resin composition comprising: (A) a liquid crystalline polymer; (B) a fibrous filler; and (C) a platy filler. The above-mentioned (A) liquid crystalline polymer has only the following constituent units (I) -(VI), as an essential component: the content of the constituent unit (I) to the total constituent unit is 50 to 70 mol%, and the content of the constituent unit (II) to the total constituent unit is 0.5 or more but less than 4.5 mol %, the content of the constituent unit (III) to the total constituent unit is 10.25-22.25 mol%, the content of the constituent unit (IV) to the total constituent unit is 0.5 or more but less than 4.5 mol%, and the constituent unit (V) is the total constituent The content of the unit is 5.75 to 23.75 mol%, the content of the constituent unit (VI) to the total constituent unit is 1 to 7 mol%, and the sum of the constituent unit (II) and the constituent unit (IV) to the total constituent unit content is 1 mol or more but less than 5 mol%, the total content of constituent units (I) ~ (VI) to all constituent units is 100 mol%, constituent unit (VI) vs. constituent unit (V) and constituent unit (VI) The total molar ratio of is 0.04~0.37, which shows optical anisotropy when melted, the weight average fiber length of the above (B) fibrous filler is 200μm or less, and the above (A) liquid crystallinity Polymer, 35 to 82.5% by mass for the total composite resin composition, the above (B) fibrous filler, 1.5 to 17.5% by mass for the total composite resin composition, the above (C) plate filler, for the composite resin The total composition is 12.5 to 47.5% by mass, and the total amount of the above (B) fibrous filler and the above (C) platy filler is 17.5 to 65% by mass for the total composite resin composition:

The composite resin composition described in item 1 of the scope of the patent application, wherein the total molar number of the constituent unit (III) and the constituent unit (IV) is the sum of the molar number of the constituent unit (V) and the constituent unit (VI) 1 to 1.1 times or 1 to 1.1 times the total molar number of the constituent unit (V) and the constituent unit (VI) of the total molar number of the constituent unit (III) and the constituent unit (IV). The composite resin composition according to item 1 or 2 of the scope of patent application, wherein the above-mentioned (B) fibrous filler is a ground fiber. The composite resin composition according to claim 1 or 2, wherein the above-mentioned (C) platy filler system talc and mica are selected from one or more types. A connector is formed from the composite resin composition described in any one of items 1 to 4 in the scope of the patent application, and the total length of the product is less than 30 mm, and the height of the product is less than 5 mm. The connector described in item 5 of the scope of patent application is a short-type narrow-pitch connector. Such as the connector described in item 5 or 6 of the scope of patent application, the distance between the intervals is 0.5mm or less, the total length of the product is 3.5mm or more, the product height is 4.0mm or less, board-to-board connector or flexible printed circuit Low-profile, narrow-pitch connectors for board connectors.

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