CN109790379B

CN109790379B - Composite resin composition and electronic component molded from same

Info

Publication number: CN109790379B
Application number: CN201780058316.8A
Authority: CN
Inventors: 深津博树; 泷智弘
Original assignee: Polyplastics Co Ltd
Current assignee: Polyplastics Co Ltd
Priority date: 2016-10-07
Filing date: 2017-09-26
Publication date: 2020-04-07
Anticipated expiration: 2037-09-26
Also published as: JP6345376B1; KR102058121B1; TWI711644B; WO2018066416A1; JPWO2018066416A1; CN109790379A; KR20190026037A; TW201827483A

Abstract

The invention provides a composite resin composition which can obtain an electronic component with excellent heat resistance and inhibited generation of warping deformation and foaming, and an electronic component formed by the composite resin composition. The composite resin composition of the present invention comprises: (A) the liquid crystalline polymer (A) is a wholly aromatic polyester amide which contains a predetermined amount of the following constituent units (I) to (VI) as essential constituent components and exhibits optical anisotropy when melted, and the fibrous filler (B) has a weight average fiber length of 250 [ mu ] m or more.

Description

Composite resin composition and electronic component molded from same

Technical Field

The present invention relates to a composite resin composition and an electronic component molded from the composite resin composition.

Background

The liquid crystalline polymer is a thermoplastic resin having excellent dimensional accuracy, flowability, and the like. With such characteristics, liquid crystalline polymers have been used as materials for various electronic components.

In particular, with the recent increase in performance of electronic devices, demands have arisen in times of high heat resistance of connectors (improvement in productivity by mounting technology), high density (multi-core), and miniaturization, and a liquid crystalline polymer composition reinforced with glass fibers has been used as a connector material by utilizing the characteristics of the liquid crystalline polymer.

However, in recent years, the connector has been further reduced in thickness and size, and due to insufficient rigidity due to insufficient thickness of the molded product and internal stress due to insertion of the metal terminal, warpage occurs after molding and during reflow heating, which causes poor soldering with the substrate. That is, in the conventional reinforcement using only glass fibers, when the amount of glass fibers added is increased in order to increase the rigidity, there is a problem that the resin is not filled in the thin portion or the embedded terminal is deformed by the pressure at the time of molding.

In order to solve such a problem of warpage, a molding method has been studied, and it has been proposed to blend a specific plate-like filler from the material viewpoint. That is, in the case of most of the general connectors (electronic components) on the market, by providing a gate position and design for maintaining symmetry during molding, it is possible to control the dimensional accuracy and warpage of the product, and further, by using a low warpage material which has been proposed in the past, it is possible to obtain a product with less warpage deformation.

However, with the recent complication of the shape of electronic components, it has been demanded to provide an asymmetric electronic component having no symmetry with respect to any of the XY-axis plane, the YZ-axis plane, and the XZ-axis plane of a molded product. As a typical example of the asymmetric electronic component, a connector for a memory module having a locking structure (having fixing claws at both ends) such as a DDR-DIMM connector is given. Particularly, a connector for a memory module for a notebook computer has a locking structure for mounting and a notch for alignment, and thus has a very complicated shape.

In the case of such an asymmetric electronic component, there is a limit to improvement of warpage deformation from the viewpoint of a molding method, because the asymmetric electronic component does not have symmetry unlike a general connector (symmetric electronic component) having symmetry with respect to any axial plane of an XY axial plane, a YZ axial plane, and an XZ axial plane of a molded product. In the case of an asymmetric electronic component having a complicated shape, the orientation of the resin and the filler in the molded article becomes complicated, and further, higher fluidity is required, and suppression of warpage is more difficult.

As a technique for solving such a problem, for example, patent document 1 discloses an asymmetric electronic component which is molded from a liquid crystalline polymer composition in which a specific fibrous filler and a specific plate-like filler are blended in a specific amount, and which has no symmetry with respect to any of the XY-axis plane, the YZ-axis plane, and the XZ-axis plane of the molded product.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2008/023839

Disclosure of Invention

Problems to be solved by the invention

However, the conventional liquid crystalline polymer composition such as the liquid crystalline polymer composition disclosed in patent document 1 cannot be fully coped with due to a change in shape, particularly, a reduction in pitch distance, product height, an increase in the number of poles, and the like, which are accompanied by an increase in integration ratio of asymmetric electronic components in recent years. That is, the conventional liquid crystalline polymer composition has insufficient heat resistance and flowability, and it is difficult to obtain an asymmetric electronic component in which warpage deformation is suppressed by using such a liquid crystalline polymer composition.

In addition, the liquid crystalline polymer composition may cause a problem of foaming. That is, a liquid crystalline polyester amide as a liquid crystalline polymer is excellent in high temperature thermal stability, and therefore, is often used for a material requiring heat treatment at a high temperature. However, when the molded article is left in air or liquid at a high temperature for a long time, a problem arises in that fine projections called blisters are generated on the surface. This phenomenon is caused as follows: decomposition gas generated when the liquid crystalline polyester amide is in a molten state enters the inside of the molded article, and the gas expands when a high-temperature heat treatment is performed thereafter, so that the surface of the molded article softened by heating is lifted up, and the lifted-up portion is expressed in the form of bubbles. The occurrence of foaming can also be reduced by sufficiently degassing the material from the vent hole during melt extrusion, preventing the material from staying in the molding machine for a long time during molding, and the like. However, the condition range is very narrow, and it is not sufficient to obtain a molded article in which the occurrence of foaming is suppressed, that is, a molded article having foaming resistance. In order to fundamentally solve the problem of the occurrence of foaming, it is required to improve the quality of the liquid crystalline polyester amide itself, and the known liquid crystalline polyester amide and the method using the same are not sufficient for solving the problem of the occurrence of foaming.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a composite resin composition which can provide an electronic component having excellent heat resistance and suppressed occurrence of warpage and foaming, and an electronic component molded from the composite resin composition.

Means for solving the problems

The present inventors have found that the above-mentioned problems can be solved by combining a liquid crystalline polymer containing a specific amount of a specific constituent unit, a fibrous filler, and a plate-like filler and setting the weight-average fiber length of the fibrous filler to 250 μm or more. 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 liquid crystalline polymer (A) is a wholly aromatic polyester amide containing the following constituent units (I) to (VI) as essential constituent components and exhibiting optical anisotropy when melted,

the content of the constituent unit (I) is 50to 70 mol% based on the total constituent units,

the content of the constituent unit (II) is 0.5 mol% or more and less than 4.5 mol% based on the whole constituent units,

the content of the constituent unit (III) is 10.25 to 22.25 mol% based on the total constituent units,

the content of the constituent unit (IV) is 0.5 mol% or more and less than 4.5 mol% based on the whole constituent units,

the content of the constituent unit (V) is 5.75 to 23.75 mol% based on the total constituent units,

the content of the constituent unit (VI) is 1 to 7 mol% based on the whole constituent units,

the total content of the constituent unit (II) and the constituent unit (IV) is 1 mol% or more and less than 5 mol% based on the total constituent units,

the total content of the constituent units (I) to (VI) is 100 mol% based on the total constituent units,

the molar ratio of the constituent unit (VI) to the total of the constituent unit (V) and the constituent unit (VI) is 0.04 to 0.37,

the fibrous filler (B) has a weight-average fiber length of 250 μm or more,

the amount of the liquid crystalline polymer (A) is 37.5 to 82.5% by mass based on the entire composite resin composition,

the fibrous filler (B) is 2.5 to 17.5% by mass based on the entire composite resin composition,

the plate-like filler (C) is 15 to 45 mass% based on the entire composite resin composition,

the total amount of the fibrous filler (B) and the plate-like filler (C) is 17.5 to 62.5% by mass based on the entire composite resin composition.

(2) The composite resin composition according to (1), wherein the total molar number of the constituent unit (III) and the constituent unit (IV) is 1 to 1.1 times the total molar number of the constituent unit (V) and the constituent unit (VI), or the total molar number of the constituent unit (V) and the constituent unit (VI) is 1 to 1.1 times 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 fibrous filler (B) is a glass fiber.

(4) The composite resin composition according to any one of (1) to (3), wherein the plate-like filler (C) is talc.

(5) An electronic component molded from the composite resin composition according to any one of (1) to (4), wherein the overall length of the product is 30mm or more and the height of the product is 5mm or more.

(6) The electronic component according to (5), which is an asymmetric electronic component having no symmetry with respect to any of an XY-axis plane, a YZ-axis plane, and an XZ-axis plane of a molded article.

(7) The electronic component according to the item (5) or (6), which is a connector for a memory module having an inter-pitch distance of 0.6mm or less, a product total length of 60.0mm or more, a product height of 10.0mm or less, and a pole number of 200 poles or more.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a composite resin composition capable of providing an electronic component having excellent heat resistance and suppressed occurrence of warpage and foaming, and an electronic component molded from the composite resin composition can be provided.

Drawings

FIG. 1 is a diagram showing a DDR-DIMM connector as formed in an embodiment. Note that a denotes a gate position.

FIG. 2 is a view showing the measurement position in the warpage measurement of the DDR-DIMM connector in the example.

Detailed Description

Hereinafter, embodiments of the present invention will be specifically described.

[ composite resin composition ]

The composite resin composition of the present invention comprises a specific liquid crystalline polymer, a fibrous filler and a plate-like filler in respective predetermined amounts, and the weight-average fiber length of the fibrous filler is 250 μm or more. The components constituting the composite resin composition of the present invention will be described below.

(liquid Crystal Polymer)

The composite resin composition of the present invention contains a liquid crystalline polymer as the wholly aromatic polyester amide. Since the wholly aromatic polyester amide has a low melting point, the processing temperature can be lowered, and the generation of decomposition gas during melting can be suppressed. As a result, the composite resin composition containing the wholly aromatic polyester amide can be molded into a molded article in which the occurrence of foaming is suppressed and the foaming resistance is improved. The liquid crystalline polymer may be used alone in 1 kind or in combination of 2 or more kinds.

The wholly aromatic polyester amide of the present invention comprises the following structural unit (I), the following structural unit (II), the following structural unit (III), the following structural unit (IV), the following structural unit (V), and the following structural unit (VI).

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

The constituent unit (II) is derived from 6-hydroxy-2-naphthoic acid (hereinafter also referred to as "HNA"). The wholly aromatic polyester amide of the present invention contains the constituent unit (II) in an amount of 0.5 mol% or more and less than 4.5 mol% based on the total constituent units. When the content of the constituent unit (II) is less than 0.5 mol%, or 4.5 mol% or more, at least one of the melting point and the heat resistance tends to be insufficient. The content of the constituent unit (II) is preferably 0.75 to 3.75 mol%, more preferably 1 to 3 mol%, from the viewpoint of achieving both low melting point and heat resistance.

The constituent unit (III) is derived from 1, 4-benzenedicarboxylic acid (hereinafter also referred to as "TA"). The wholly aromatic polyester amide of the present invention contains 10.25 to 22.25 mol% of the constituent unit (III) with respect to the total constituent units. When the content of the constituent unit (III) is less than 10.25 mol% or exceeds 22.25 mol%, at least one of the melting point and the heat resistance tends to be insufficient. The content of the constituent unit (III) is preferably 12.963 to 20.75 mol%, more preferably 15.675 to 19.25 mol%, from the viewpoint of achieving both low melting point and heat resistance.

The constituent unit (IV) is derived from 1, 3-benzenedicarboxylic acid (hereinafter also referred to as "IA"). The wholly aromatic polyester amide of the present invention contains the constituent unit (IV) in an amount of 0.5 mol% or more and less than 4.5 mol% based on the total constituent units. When the content of the constituent unit (IV) is less than 0.5 mol%, or 4.5 mol% or more, at least one of the melting point and the heat resistance tends to be insufficient. The content of the constituent unit (IV) is preferably 0.5 to 3.75 mol%, more preferably 0.5 to 3 mol%, from the viewpoint of achieving both the low melting point and the heat resistance.

The constituent unit (V) is derived from 4, 4' -dihydroxybiphenyl (hereinafter also referred to as "BP"). The wholly aromatic polyester amide of the present invention contains 5.75 to 23.75 mol% of the constituent unit (V) based on the total constituent units. When the content of the constituent unit (V) is less than 5.75 mol% or exceeds 23.75 mol%, at least one of the melting point and the heat resistance tends to be insufficient. The content of the constituent unit (V) is preferably 8.5 to 20.375 mol%, more preferably 11.25 to 17 mol% (e.g., 11.675 to 17 mol%) from the viewpoint of achieving both the low melting point and the heat resistance.

The constituent unit (VI) is derived from N-acetyl-p-aminophenol (hereinafter also referred to as "APAP"). The wholly aromatic polyester amide of the present invention contains 1 to 7 mol% of the constituent unit (VI) based on the total constituent units. When the content of the constituent unit (VI) is less than 1 mol% or more than 7 mol%, at least one of the melting point and the heat resistance tends to be insufficient. The content of the constituent unit (VI) is preferably 1.5 to 7 mol%, more preferably 2 to 7 mol%, from the viewpoint of achieving both low melting point and heat resistance.

The wholly aromatic polyester amide of the present invention contains the constituent unit (II) and the constituent unit (IV) in a total amount of 1 mol% or more and less than 5 mol% with respect to the total constituent units. In the wholly aromatic polyester amide, the total amount of the above range is sufficient to allow both of the low melting point and the heat resistance to be easily achieved by allowing the structural unit (II) having flexibility of a naphthalene skeleton and the structural unit (IV) having flexibility of a benzene skeleton to coexist. When the total content is less than 1 mol%, the ratio of the constituent units having flexibility is too small, and thus the melting point tends to be insufficient. When the total content is 5 mol% or more, the ratio of the constituent units having flexibility becomes too large, and thus the heat resistance tends to become insufficient. From the viewpoint of achieving both low melting point and heat resistance, the total content is preferably 1.75 to 4.75 mol%, more preferably 2.5 to 4.5 mol%.

In the wholly aromatic polyester amide of the present invention, the molar ratio of the constituent unit (VI) to the total of the constituent unit (V) and the constituent unit (VI) is 0.04 to 0.37. When the molar ratio is less than 0.04, the proportion of the constituent unit having a biphenyl skeleton increases, and therefore, the wholly aromatic polyester amide tends to have low crystallinity, and the low melting point and the heat resistance tend to be insufficient. When the molar ratio exceeds 0.37, the number of different bonds other than the ester bond increases, and therefore, the crystallinity of the wholly aromatic polyester amide becomes low, and the low melting point and the heat resistance are liable to be insufficient. The molar ratio is preferably 0.07 to 0.36, more preferably 0.11 to 0.35, from the viewpoint of achieving both the low melting point and the heat resistance.

From the viewpoint of achieving both low melting point and heat resistance, it is preferable that the total number of moles (hereinafter also referred to as "1A" moles) of the constituent unit (III) and the constituent unit (IV) is 1 to 1.1 times the total number of moles (hereinafter also referred to as "2A" moles) of the constituent unit (V) and the constituent unit (VI), or the total number of moles of the constituent unit (V) and the constituent unit (VI) is 1 to 1.1 times the total number of moles of the constituent unit (III) and the constituent unit (IV). More preferably, the mole number 1A is 1.02 to 1.06 times the mole number 2A, or the mole number 2A is 1.02 to 1.06 times the mole number 1A. More preferably, the mole number 1A is 1.024 to 1.056 times the mole number 2A, or the mole number 2A is 1.024 to 1.056 times the mole number 1A.

As described above, the wholly aromatic polyester amide of the present invention contains the specific constituent units (I) to (VI) and the sum of the constituent unit (II) and the constituent unit (IV) in specific amounts with respect to all the constituent units, and the molar ratio of the constituent unit (VI) with respect to the sum of the constituent unit (V) and the constituent unit (VI) is in a specific range, so that both low melting point and heat resistance are sufficiently achieved. The wholly aromatic polyester amide of the present invention contains the constituent units (I) to (VI) in a total amount of 100 mol% based on the total constituent units.

As an index indicating the heat resistance, a deflection temperature under load (hereinafter, also referred to as "DTUL") is given. When DTUL is 260 ℃ or higher, heat resistance tends to be high, and it is preferable. DTUL is a value obtained by measuring a state of a polyester amide resin composition obtained by melt-kneading 60 mass% of the wholly aromatic polyester amide and 40 mass% of milled fibers having an average fiber diameter of 11 μm and an average fiber length of 75 μm at the melting point of the wholly aromatic polyester amide +20 ℃, and can be measured in accordance with ISO75-1, 2. From the viewpoint of achieving both low melting point and heat resistance, DTUL is preferably 265 ℃ or higher and 310 ℃ or lower, and more preferably 267 to 300 ℃.

The method for producing the wholly aromatic polyester amide of the present invention will be described below. The wholly aromatic polyester amide of the present invention is polymerized by a direct polymerization method, an ester exchange method, or the like. In the polymerization, a melt polymerization method, a solution polymerization method, a slurry polymerization method, a solid phase polymerization method, or the like, or a combination of 2 or more of these methods is used, and preferably a melt polymerization method or a combination of a melt polymerization method and a solid phase polymerization method is used.

In the present invention, an acylating agent for a polymerizable monomer and a monomer having an activated terminal as an acid chloride derivative can be used for polymerization. Examples of the acylating agent include fatty acid anhydrides such as acetic anhydride.

In these polymerizations, various catalysts can be used, and typical catalysts include: dialkyl tin oxide, diaryl tin oxide, titanium dioxide, alkoxy titanium silicate, titanium alkoxideAcids, fatty acid metal salts, BF₃Lewis acid salts such as Lewis acid salts, and fatty acid metal salts are preferred. The amount of the catalyst used is usually about 0.001 to 1% by mass, particularly preferably about 0.003 to 0.2% by mass, based on the total mass of the monomers.

In addition, in the case of performing solution polymerization or slurry polymerization, liquid paraffin, highly heat-resistant synthetic oil, inactive mineral oil, or the like is used as a solvent.

The reaction conditions include, for example, a reaction temperature of 200 to 380 ℃ and a final pressure of 0.1 to 760Torr (i.e., 13 to 101,080 Pa). In particular, the reaction temperature is, for example, 260 to 380 ℃, preferably 300 to 360 ℃, and the final pressure is 1 to 100Torr (i.e., 133 to 13,300Pa), preferably 1 to 50Torr (i.e., 133 to 6,670Pa) in the melting reaction.

The reaction may be started by charging all of the raw material monomers (HBA, HNA, TA, IA, BP, and APAP), the acylating agent, and the catalyst into the same reaction vessel (one-stage method), or may be started by acylating the hydroxyl groups of the raw material monomers HBA, HNA, BP, and APAP with the acylating agent and then reacting the acylated hydroxyl groups with the carboxyl groups of TA and IA (two-stage method).

The melt polymerization is carried out after the temperature in the reaction system reaches a predetermined temperature and then the pressure is reduced to a predetermined reduced pressure. After the torque of the stirrer reached a predetermined value, an inert gas was introduced, the pressure was reduced from a reduced pressure state to a normal pressure state, and the wholly aromatic polyester amide was discharged from the reaction system.

The wholly aromatic polyester amide produced by the above polymerization method can be increased in molecular weight by further performing solid-phase polymerization by heating in an inert gas under normal pressure or reduced pressure x. The solid-phase polymerization is preferably carried out under conditions of a reaction temperature of 230 to 350 ℃, preferably 260 to 330 ℃ and a final pressure of 10to 760Torr (i.e., 1,330 to 101,080 Pa).

The method for producing a wholly aromatic polyester amide of the present invention preferably comprises the steps of: acylating 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 4' -dihydroxybiphenyl, and N-acetyl-p-aminophenol with a fatty acid anhydride in the presence of a fatty acid metal salt, and then transesterifying with 1, 4-benzenedicarboxylic acid and 1, 3-benzenedicarboxylic acid,

with respect to all monomers comprising 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 1, 4-benzenedicarboxylic acid, 1, 3-benzenedicarboxylic acid, 4' -dihydroxybiphenyl, and N-acetyl-p-aminophenol,

the amount of 4-hydroxybenzoic acid used is 50to 70 mol%, preferably 54 to 67 mol%, more preferably 58 to 64 mol%, from the viewpoint of achieving both low melting point and heat resistance,

the amount of 6-hydroxy-2-naphthoic acid used is 0.5 mol% or more and less than 4.5 mol%, preferably 0.75 to 3.75 mol%, more preferably 1 to 3 mol% from the viewpoint of achieving both low melting point and heat resistance,

the amount of 1, 4-benzenedicarboxylic acid used is 10.25 to 22.25 mol%, preferably 12.963 to 20.75 mol%, more preferably 15.675 to 19.25 mol%, from the viewpoint of achieving both low melting point and heat resistance,

the amount of 1, 3-benzenedicarboxylic acid used is 0.5 mol% or more and less than 4.5 mol%, preferably 0.5 to 3.75 mol%, more preferably 0.5 to 3 mol% from the viewpoint of achieving both low melting point and heat resistance,

the amount of 4, 4' -dihydroxybiphenyl used is 5.75 to 23.75 mol%, preferably 8.5 to 20.375 mol%, more preferably 11.25 to 17 mol% (e.g., 11.675 to 17 mol%) from the viewpoint of achieving both low melting point and heat resistance,

the amount of N-acetyl-p-aminophenol used is 1 to 7 mol%, preferably 1.5 to 7 mol%, more preferably 2 to 7 mol%, from the viewpoint of achieving both low melting point and heat resistance,

the total amount of 6-hydroxy-2-naphthoic acid and 1, 3-benzenedicarboxylic acid used is 1 mol% or more and less than 5 mol%, preferably 1.75 to 4.75 mol%, more preferably 2.5 to 4.5 mol%, from the viewpoint of achieving both low melting point and heat resistance,

the total amount of 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 1, 4-benzenedicarboxylic acid, 1, 3-benzenedicarboxylic acid, 4' -dihydroxybiphenyl, and N-acetyl-p-aminophenol used is preferably 100 mol%,

the molar ratio of the amount of N-acetyl-p-aminophenol used to the total amount of 4, 4' -dihydroxybiphenyl and N-acetyl-p-aminophenol used is 0.04 to 0.37, preferably 0.07 to 0.36, more preferably 0.11 to 0.35, from the viewpoint of achieving both low melting point and heat resistance,

the amount of the fatty acid anhydride used is preferably 1.02 to 1.04 times the total hydroxyl equivalent of 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 4' -dihydroxybiphenyl, and N-acetyl-p-aminophenol. More preferably, the fatty acid metal salt is acetic acid metal salt, and the fatty acid anhydride is acetic anhydride. Further, it is more preferable that the total molar number of 1, 4-benzenedicarboxylic acid and 1, 3-benzenedicarboxylic acid (hereinafter also referred to as "molar number 1B") is 1 to 1.1 times the total molar number of 4,4 '-dihydroxybiphenyl and N-acetyl-p-aminophenol (hereinafter also referred to as "molar number 2B"), or the total molar number of 4, 4' -dihydroxybiphenyl and N-acetyl-p-aminophenol is 1 to 1.1 times the total molar number of 1, 4-benzenedicarboxylic acid and 1, 3-benzenedicarboxylic acid. More preferably, the molar number 1B is 1.02 to 1.06 times the molar number 2B, or the molar number 2B is 1.02 to 1.06 times the molar number 1B. Particularly preferably, the mole number 1B is 1.024 to 1.056 times the mole number 2B, or the mole number 2B is 1.024 to 1.056 times the mole number 1B.

The properties of the wholly aromatic polyester amide will be described below. The wholly aromatic polyester amide of the present invention exhibits optical anisotropy when melted. The wholly aromatic polyester amide of the present invention shows optical anisotropy when melted, meaning that it is a liquid crystalline polymer.

In the present invention, it is essential for the wholly aromatic polyester amide to be a liquid crystalline polymer to have both thermal stability and easy processability. The wholly aromatic polyester amide composed of the above-mentioned constituent units (I) to (VI) may not form an anisotropic melt phase depending on the sequence distribution in the constituent components and the polymer, and the polymer of the present invention is limited to the wholly aromatic polyester amide showing optical anisotropy when melted.

The properties of melt anisotropy can be confirmed by a conventional polarized light inspection method using a crossed polarizing plate. More specifically, confirmation of melt anisotropy may be performed as follows: the sample placed on a heating stage manufactured by Linkam was melted using a polarizing microscope manufactured by olympus corporation, and observed at a magnification of 150 times under a nitrogen atmosphere. The liquid crystalline polymer is optically anisotropic and transmits light when inserted between crossed polarizers. When the sample is optically anisotropic, polarized light transmits even in a molten stationary liquid state, for example.

Since a nematic liquid crystalline polymer is significantly reduced in viscosity at a temperature equal to or higher than the melting point, it generally shows liquid crystallinity as an index of processability at a temperature equal to or higher than the melting point. From the viewpoint of heat resistance, the melting point is preferably as high as possible, but 360 ℃ or lower is a preferable standard in consideration of thermal deterioration in melt processing of the polymer, heating capacity of a molding machine, and the like. More preferably, the temperature is 300 to 360 ℃, and still more preferably 340 to 358 ℃.

The melt viscosity of the wholly aromatic polyester amide in the present invention is preferably 500 pas or less, more preferably 0.5 to 300 pas, and even more preferably 1 to 100 pas at a temperature 10to 30 ℃ higher than the melting point of the wholly aromatic polyester amide and at a shear rate of 1000/sec. When the melt viscosity is within the above range, the wholly aromatic polyester amide itself or a composition containing the wholly aromatic polyester amide is likely to have fluidity during molding, and the filling pressure is unlikely to be excessive. In the present specification, the melt viscosity refers to a melt viscosity measured in accordance with ISO 11443.

As an index for the heat resistance, the difference between the melting point and DTUL is also included. When the difference is 90 ℃ or less, the heat resistance tends to be high, and it is preferable. From the viewpoint of achieving both low melting point and heat resistance, the difference is preferably more than 0 ℃ and 85 ℃ or less (for example, 50 ℃ or more and 85 ℃ or less), and more preferably 55 to 79 ℃.

The composite resin composition of the present invention contains 37.5 to 82.5 mass% of the liquid crystalline polymer in the composite resin composition with respect to the entire composite resin composition. When the content of the liquid crystalline polymer is less than 37.5% by mass based on the entire composite resin composition, the flowability of the composite resin composition is liable to deteriorate, and the warpage of a molded article such as an electronic component obtained from the composite resin composition may become large, which is not preferable. If the content of the liquid crystalline polymer exceeds 82.5% by mass of the entire composite resin composition, the flexural modulus and crack resistance of a molded article such as an electronic component obtained from the composite resin composition are undesirably reduced. The composite resin composition of the present invention preferably contains the liquid crystalline polymer in an amount of 44 to 75 mass%, more preferably 60to 65 mass%, based on the entire composite resin composition.

(fibrous Filler)

The composite resin composition of the present invention comprises the liquid crystalline polymer and a fibrous filler, and the weight average fiber length of the fibrous filler is 250 μm or more, and therefore, a molded article obtained by molding the composite resin composition is excellent in high-temperature rigidity and is suppressed in warp deformation. The fibrous filler may be used alone in 1 kind or in combination of 2 or more kinds. The fibrous filler of the present invention is not particularly limited, and examples thereof include glass fibers, milled fibers, carbon fibers, asbestos fibers, silica-alumina fibers, zirconia fibers, boron nitride fibers, silicon nitride fibers, boron fibers, potassium titanate fibers, and the like. Since the molded article obtained from the composite resin composition is likely to have improved high-temperature rigidity, glass fibers are preferred as the fibrous filler of the present invention.

In the composite resin composition of the present invention, the weight-average fiber length of the fibrous filler is 250 μm or more, preferably 350 μm or more, and more preferably 450 μm or more. When the weight-average fiber length is less than 250 μm, the molded article obtained from the composite resin composition is not likely to have sufficient high-temperature rigidity, and the molded article may have large warpage. The upper limit of the weight-average fiber length is not particularly limited, but is preferably 700 μm or less, and more preferably 500 μm or less. When the weight-average fiber length is 600 μm or less, the composite resin composition is preferable because flowability is good and warpage of a molded article is not likely to increase. In the present specification, the weight average fiber length of the fibrous filler means a weight average fiber length obtained by heating the composite resin composition at 600 ℃ for 2 hours to ash the ash residue, dispersing the ash residue in a 5 mass% aqueous polyethylene glycol solution to obtain a dispersion, and measuring the dispersion with an image measuring instrument.

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

The composite resin composition of the present invention contains a fibrous filler in an amount of 2.5 to 17.5 mass% relative to the entire composite resin composition. When the content of the fibrous filler is less than 2.5% by mass based on the entire composite resin composition, the load deflection temperature of a molded article such as an electronic component obtained from the composite resin composition is low, and the high-temperature rigidity is insufficient, which is not preferable. When the content of the fibrous filler exceeds 17.5 mass% based on the entire composite resin composition, the flowability of the composite resin composition is deteriorated, and warpage of the molded article may be increased, which is not preferable. The fibrous filler of the present invention is preferably contained in the composite resin composition in an amount of 4 to 16% by mass, more preferably 5to 15% by mass, based on the entire composite resin composition.

(plate-shaped Filler)

The composite resin composition of the present invention further contains a plate-like filler. By including the plate-like filler in the composite resin composition of the present invention, a molded article in which warpage is suppressed can be obtained. The plate-like filler may be used alone in 1 kind or in combination of 2 or more kinds.

The composite resin composition contains 15 to 45 mass% of a plate-like filler relative to the entire composite resin composition. If the content of the plate-like filler is less than 15% by mass based on the entire composite resin composition, warpage of a molded article such as an electronic component obtained from the composite resin composition may increase, which is not preferable. When the content of the plate-like filler exceeds 45 mass% of the entire composite resin composition, the flowability of the composite resin composition may be deteriorated, which is not preferable. The plate-like filler of the present invention is preferably contained in the composite resin composition in an amount of 20 to 40% by mass, more preferably 25 to 35% by mass, based on the entire composite resin composition.

The plate-like filler of the present invention includes talc, mica, glass flakes, various metal foils, and the like, and talc is preferable in that the fluidity of the composite resin composition is not deteriorated and warpage of a molded article obtained from the composite resin composition is suppressed. The average particle diameter of the plate-like filler is not particularly limited, but is preferably small in consideration of fluidity in the thin portion. On the other hand, in order to reduce warpage of a molded article such as an electronic component obtained from the composite resin composition, it is necessary to maintain a certain level. Specifically, the thickness is preferably 1 to 100 μm, more preferably 5to 50 μm.

[ Talc ]

As the talc which can be used in the present invention, it is preferable that Fe is contained in the total amount of solid components of the talc₂O₃、Al₂O₃And a total content of CaO of 2.5 mass% or less, Fe₂O₃And Al₂O₃The content of CaO exceeds 1.0 mass% and is 2.0 mass% or less, and the content of CaO is less than 0.5 mass%. That is, talc that can be used in the present invention is other than SiO as its main component₂And may contain Fe in addition to MgO₂O₃、Al₂O₃And at least 1 of CaO, and each component is contained in the above content range.

Among the above talcs, Fe₂O₃、Al₂O₃And CaO in a total amount of 2.5% by mass or less, the composite resin composition is less likely to be deteriorated in moldability and heat resistance of a molded article such as an electronic component molded from the composite resin composition. Fe₂O₃、Al₂O₃And the total content of CaO is preferably 1.0 mass% or more and 2.0 mass% or less.

Further, among the above talcs, Fe₂O₃And Al₂O₃Talc in a total content of more than 1.0 mass% is easily obtained. Further, the aboveIn talc, Fe₂O₃And Al₂O₃When the total content of (a) is 2.0% by mass or less, the moldability of the composite resin composition and the heat resistance of a molded article such as an electronic component molded from the composite resin composition are not easily deteriorated. Fe₂O₃And Al₂O₃The total content of (b) is preferably more than 1.0 mass% and 1.7 mass% or less.

Further, when the content of CaO in the talc is less than 0.5 mass%, the moldability of the composite resin composition and the heat resistance of a molded article such as an electronic component molded from the composite resin composition are not easily deteriorated. The content of CaO is preferably 0.01 mass% or more and 0.4 mass% or less.

The talc of the present invention has a mass-based or volume-based cumulative average particle diameter (D) measured by a laser diffraction method₅₀) From the viewpoint of preventing warpage of the molded article and maintaining the fluidity of the composite resin composition, it is preferably 4.0 to 20.0 μm, and more preferably 10to 18 μm.

[ mica ]

Mica is a ground silicate mineral containing aluminum, potassium, magnesium, sodium, iron, etc. Examples of mica that can be used in the present invention include muscovite, phlogopite, biotite, and synthetic mica, and among them, muscovite is preferable in terms of good color and low cost.

In the production of mica, a wet grinding method and a dry grinding method are known as methods for grinding minerals. The wet pulverization method is as follows: the mica raw stone was roughly pulverized by a dry pulverizer, and then subjected to wet pulverization in a slurry state by adding water to perform main pulverization, and then subjected to dehydration and drying. The dry grinding method is a common method at low cost as compared with the wet grinding method, but when the wet grinding method is used, it is easier to grind the mineral thin and fine. The present invention preferably uses a thin and finely pulverized product for the reason of obtaining mica having a preferable average particle diameter and thickness described later. Therefore, mica produced by wet grinding is preferably used in the present invention.

In addition, in the wet grinding method, it is necessary to grind the object to be groundIn the step of dispersing in water, in order to improve the dispersion efficiency of the pulverized material, a coagulating sedimentation agent and/or a precipitation aid is generally added to the pulverized material. Examples of the coagulating sedimentation agent and the precipitating assistant which can be used in the present invention include polyaluminum chloride, aluminum sulfate, ferrous sulfate, ferric sulfate, chlorimuron (chlorimuron copperas), ferric polysulfate, polyferric chloride, an iron-silica inorganic polymer coagulant, an iron chloride-silica inorganic polymer coagulant, and slaked lime (Ca (OH)₂) Caustic soda (NaOH), soda ash (Na)₂CO₃) And the like. The pH of these coagulants and precipitation aids is either basic or acidic. The mica used in the present invention is preferably subjected to wet grinding without using a coagulating sedimentation agent and/or a precipitation aid. When mica which is not treated with a coagulating precipitant and/or a precipitating assistant is used, the polymer in the composite resin composition is less likely to be decomposed, a large amount of gas is less likely to be generated, the molecular weight of the polymer is less likely to be reduced, and the like, and therefore, the performance of the obtained molded article such as an electronic component can be more easily maintained.

The mica used in the present invention preferably has an average particle diameter of 10to 100 μm, particularly preferably 20 to 80 μm, as measured by Microtrac laser diffraction method. An average particle size of mica of 10 μm or more is preferable because the effect of improving the rigidity of a molded article is likely to be sufficient. When the average particle size of mica is 100 μm or less, the rigidity of the molded article is likely to be sufficiently improved, and the weld strength is also likely to be sufficient, which is preferable. Further, when the average particle diameter of mica is 100 μm or less, sufficient fluidity for molding the electronic component and the like of the present invention can be easily secured.

The thickness of the mica that can be used in the present invention is preferably 0.01 to 1 μm, particularly preferably 0.03 to 0.3 μm, as actually measured by observation with an electron microscope. When the thickness of mica is 0.01 μm or more, the mica is less likely to be broken during melt processing of the composite resin composition, and therefore, the rigidity of the molded article may be easily improved, which is preferable. When the thickness of mica is 1 μm or less, the effect of improving the rigidity of the molded article tends to be sufficient, and therefore, mica is preferable.

Mica that can be used in the present invention may be surface-treated with a silane coupling agent or the like, and/or granulated with a binder to form granules.

In the composite resin composition of the present invention, the total amount of the fibrous filler and the plate-like filler is 17.5 to 62.5% by mass based on the entire composite resin composition. When the total amount is less than 17.5% by mass based on the entire composite resin composition, the load deflection temperature of a molded article such as an electronic component obtained from the composite resin composition is low, the high-temperature rigidity is insufficient, and the warp deformation may become large, which is not preferable. When the total amount exceeds 62.5 mass% based on the entire composite resin composition, the flowability of the composite resin composition is deteriorated and warpage of a molded article may be increased, which is not preferable. The total amount is preferably 25 to 56% by mass, and more preferably 35 to 40% by mass, based on the entire composite resin composition.

(other Components)

The composite resin composition of the present invention may further contain 1 or more of a nucleating agent, a pigment such as carbon black or inorganic sintering fuel, an antioxidant, a stabilizer, a plasticizer, a lubricant, a release agent, a flame retardant, and a known inorganic filler, in addition to the above components.

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 and the weight average fiber length of the fibrous filler is 250 μm or more, and can be appropriately selected from conventionally known methods for producing resin compositions. Examples thereof include: a method in which the respective components are melt-kneaded and extruded using a melt-kneading apparatus such as a single-screw or twin-screw extruder, and the resulting composite resin composition is processed into a desired form such as powder, flake, pellet, or the like.

The composite resin composition of the present invention has excellent fluidity, and therefore, the minimum filling pressure during molding is not likely to become excessive, and it can be preferably molded into electronic components, particularly, components having a complicated shape such as asymmetric electronic components having a locking structure, notches, and the like. The degree of fluidity is judged by the minimum fill pressure of the connector. That is, the minimum injection filling pressure at which a good molded product can be obtained in the injection molding of the DDR-DIMM connector shown in fig. 1 is defined as the minimum filling pressure. The lower the minimum filling pressure, the more excellent the flowability was evaluated.

The melt viscosity of the composite resin composition is 1 x 10 as measured according to ISO11443 at a shear rate of 1000/sec at a temperature 10to 30 ℃ higher than the melting point of the liquid crystalline polymer⁵Pa · s or less (more preferably 5Pa · s or more and 1X 10)²Pa · s or less) is preferable from the following viewpoint: in the molding of a portion having a complicated shape in an electronic component, particularly in the molding of a portion having a complicated shape such as a locking structure or a notch in an asymmetric electronic component, the fluidity of the composite resin composition is ensured and the filling pressure does not become excessive.

(electronic parts)

The composite resin composition of the present invention is molded to obtain the electronic component of the present invention. The electronic component of the present invention is not particularly limited, and examples thereof include those having a product overall length of 30mm or more and a product height of 5mm or more. In the electronic component of the present invention, an asymmetric electronic component means an electronic component having no symmetry with respect to any axial plane of an XY axial plane, a YZ axial plane, and an XZ axial plane of a molded product.

In most general connectors (electronic components) on the market, the connector has symmetry with respect to any axial plane of an XY axial plane, a YZ axial plane, and an XZ axial plane, and the dimensional accuracy and warpage of a product can be controlled by providing a gate position and design for maintaining the symmetry during molding. On the other hand, the shape of the asymmetric electronic component is complicated, and it is difficult to suppress warpage in the molding method. The electronic component of the present invention, particularly an asymmetric electronic component, can be suppressed in warpage by using the composite resin composition of the present invention.

As typical examples of such electronic components, a connector and a socket are given.

Examples of the connector include a connector for a memory module and an interface connector. Examples of the connector for a memory module include a DIMM connector; DDR connectors such as DDR-DIMM connectors, DDR2-DIMM connectors, DDR-SO-DIMM connectors, DDR2-SO-DIMM connectors, DDR-Micro-DIMM connectors, and DDR2-Micro-DIMM connectors. Examples of the interface connector include a SATA connector, a SAS connector, and a NGFF connector. Among them, DDR connectors, SATA connectors, SAS connectors, and NGFF connectors are suitable, and particularly, thin-walled connectors for memory modules having complicated shapes, a pitch distance of 0.6mm or less, a product total length of 60.0mm or more, a product height of 10.0mm or less, and a pole number of 200 or more, which are used for notebook computers, are particularly suitable. Such a connector for a memory module is supplied to an IR reflow process for surface mounting at a peak temperature of 230 to 280 ℃, and is required to have a warpage of 0.1mm or less before undergoing the IR reflow process and a difference in warpage before and after reflow of 0.05mm or less.

Examples of the slot include memory card slots such as a card bus (CardBus), a CF card, a memory stick, a PC card, an SD card, an SDMo, a smart card, and a smart media card.

The molding method for obtaining the electronic component of the present invention is not particularly limited, and in order to obtain an electronic component in which warpage is suppressed, it is preferable to select molding conditions that do not cause residual internal stress. In order to reduce the filling pressure and reduce the residual internal stress of the obtained electronic component, the cylinder temperature of the molding machine is preferably a temperature equal to or higher than the melting point of the liquid crystalline polymer.

In addition, the temperature of the die is preferably 70-100 ℃. When the mold temperature is low, the flow of the composite resin composition filled in the mold may be poor, which is not preferable. When the mold temperature is high, a problem such as occurrence of burrs may occur, which is not preferable. The injection rate is preferably 150 mm/sec or more. When the injection speed is low, only unfilled molded articles may be obtained, and even if completely filled molded articles are obtained, only electronic parts having large warpage may be obtained because the filling pressure is high and the residual internal stress is large.

The electronic component of the present invention suppresses warpage. The degree of warpage of the electronic component is determined as follows. That is, in the DDR-DIMM connector shown in fig. 1, the heights are measured at a plurality of positions indicated by black dots in fig. 2, and the difference between the maximum height and the minimum height from the least square plane is taken as the warpage. The electronic component of the present invention suppresses changes in warpage before and after performing IR reflow soldering.

In addition, the electronic component of the present invention suppresses the occurrence of blistering. The degree of foaming occurred was judged by the foaming temperature. That is, the presence or absence of foaming on the surface of the molded article after 5 minutes of holding in a hot press at a predetermined temperature was visually observed, and the highest temperature at which the number of foaming occurred was zero was defined as the foaming temperature. The higher the foaming temperature, the more suppressed the foaming was evaluated.

The electronic component of the present invention is excellent in heat resistance, for example, heat resistance evaluated by high-temperature rigidity. The high temperature rigidity was evaluated by measuring the deflection temperature under load based on ISO75-1, 2.

Examples

The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

< Synthesis example 1 >

The following raw material monomers, fatty acid metal salt catalyst and acylating agent were charged into a polymerization vessel equipped with a stirrer, reflux column, monomer inlet, nitrogen gas inlet and decompression/outflow line, and nitrogen substitution was started.

(I) 9.7 mol (58 mol%) (HBA) of 4-hydroxybenzoic acid

(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 mole (5 mole%) (APAP)

Potassium acetate catalyst 110mg

Acetic anhydride 1734g (1.03 times the total hydroxyl equivalent of HBA and HNA and BP and APAP)

After the addition of the raw materials, the temperature of the reaction system was raised to 140 ℃ and reacted at 140 ℃ for 1 hour. Thereafter, the temperature was raised to 360 ℃ over a further 5.5 hours, and then the pressure was reduced to 10Torr (1330 Pa) over a further 20 minutes to carry out melt polymerization while distilling off acetic acid, excess acetic anhydride and other low-boiling components. After the stirring torque reached a predetermined value, nitrogen gas was introduced, the pressure was increased from a reduced pressure state to a normal pressure state, and the polymer was discharged from the lower portion of the polymerization vessel.

< evaluation >

The wholly aromatic polyester amide of synthesis example 1 was evaluated for melting point, melt viscosity, and DTUL according to the following methods. The evaluation results are shown in table 1.

[ melting Point ]

An endothermic peak temperature (Tm1) observed when a polymer was measured from room temperature under a temperature raising condition of 20 ℃/min was observed by DSC (manufactured by TA Instruments inc.), and then, the polymer was held at a temperature of (Tm1+40) ° c for 2 minutes, and then, the polymer was cooled down to room temperature under a temperature lowering condition of 20 ℃/min, and thereafter, the temperature of the endothermic peak observed when the polymer was measured again under a temperature raising condition of 20 ℃/min was measured.

[DTUL]

60 mass% of the polymer and 40 mass% of glass fibers (EFH 75-01, manufactured by Mitsui corporation, milled fibers, average fiber diameter of 11 μm, and average fiber length of 75 μm) were melt-kneaded by a two-shaft extruder (TEX 30 α, manufactured by Nippon Steel Co., Ltd.) at a cylinder temperature of +20 ℃ of the melting point of the polymer to obtain pellets of the polyesteramide resin composition.

The pellets of the polyester amide resin composition were molded by using a molding machine ("SE 100 DU" manufactured by Sumitomo heavy machinery industries Co., Ltd.) under the following molding conditions to obtain a test piece (4 mm. times.10 mm. times.80 mm) for measurement. Using the test piece, the deflection temperature under load was measured by a method according to ISO75-1, 2. The bending stress used was 1.8 MPa. The results are shown in Table 1.

[ Forming Condition ]

Barrel temperature: melting Point of Polymer +15 deg.C

Temperature of the die: 80 deg.C

Back pressure: 2MPa of

Injection speed: 33 mm/sec

[ melt viscosity ]

The melt viscosity of the liquid crystalline polymer was measured at a shear rate of 1000/sec based on ISO11443 using a Capirograph manufactured by Toyo Seiki Seisaku-Sho Ltd at a temperature higher than the melting point of the liquid crystalline polymer by 10to 30 ℃ and an orifice having an inner diameter of 1mm and a length of 20 mm. The measurement temperatures are shown in table 1.

< Synthesis examples 2 to 18, comparative Synthesis examples 1 to 11 >

Polymers were obtained in the same manner as in synthesis example 1, except that the types of raw material monomers and the feed ratio (mol%) were set as shown in tables 1 to 3. Further, the same evaluation as in synthesis example 1 was performed. The evaluation results are shown in tables 1 to 3.

[ Table 1]

[ Table 2]

[ Table 3]

< examples 1 to 12, comparative examples 1 to 5 >

In the following examples and comparative examples, the liquid crystalline polymer 1 was the liquid crystalline polymer obtained in synthesis example 15. The liquid crystalline polymers 2 and 3 were produced as follows.

In the present example, the melting point and the melt viscosity of the pellets were measured under the following conditions.

[ measurement of melting Point ]

The endothermic peak temperature (Tm1) observed when the liquid crystalline polymer was measured at a temperature rise condition of 20 ℃/min from room temperature was observed by a DSC manufactured by TA Instruments inc, and then, the liquid crystalline polymer was held at a temperature of (Tm1+40) ° c for 2 minutes, and then, the liquid crystalline polymer was cooled down to room temperature once at a temperature decrease condition of 20 ℃/min, and then, the temperature of the endothermic peak observed when the liquid crystalline polymer was measured again at a temperature rise condition of 20 ℃/min was measured.

[ measurement of melt viscosity ]

The melt viscosity of the liquid crystalline polymer was measured at a shear rate of 1000/sec based on ISO11443 using a Capirograph model 1B manufactured by Toyo Seiki Seisaku-Sho K.K., using an orifice having an inner diameter of 1mm and a length of 20mm at a temperature of 10to 30 ℃ higher than the melting point of the liquid crystalline polymer. The measurement temperatures were 360 ℃ for the liquid crystalline polymer 1, 350 ℃ for the liquid crystalline polymer 2, and 380 ℃ for the liquid crystalline polymer 3.

(method for producing liquid Crystal Polymer 2)

The following raw material monomers, metal catalyst and acylating agent were charged into a polymerization vessel equipped with a stirrer, reflux column, monomer inlet, nitrogen inlet and pressure reducing/outflow line, and nitrogen substitution was 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

Acetic anhydride: 1659g

After the raw materials were charged into the polymerization vessel, the temperature of the reaction system was raised to 140 ℃ and reacted at 140 ℃ for 1 hour. Thereafter, the temperature was raised to 340 ℃ for 4.5 hours, and then the pressure was reduced to 10Torr (1330 Pa) for 15 minutes, and melt polymerization was carried out while distilling off acetic acid, excess acetic anhydride, and other low-boiling components. After the stirring torque reached a predetermined value, nitrogen gas was introduced, the pressure was increased from a reduced pressure state to a pressurized state under normal pressure, the polymer was discharged from the lower part of the polymerization vessel, and the strand was pelletized to obtain pellets. The obtained pellets had a melting point of 336 ℃ and a melt viscosity of 19 pas.

(method for producing liquid Crystal Polymer 3)

(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

Acetic anhydride: 1644g

After the raw materials were charged into the polymerization vessel, the temperature of the reaction system was raised to 140 ℃ and reacted at 140 ℃ for 1 hour. Thereafter, the temperature was raised to 360 ℃ over a further 5.5 hours, and then the pressure was reduced to 5Torr (i.e., 667Pa) over a further 20 minutes to carry out melt polymerization while distilling off acetic acid, excess acetic anhydride and other low-boiling components. After the stirring torque reached a predetermined value, nitrogen gas was introduced, the pressure was increased from a reduced pressure state to a pressurized state under normal pressure, the polymer was discharged from the lower part of the polymerization vessel, and the strand was pelletized to obtain pellets. The obtained pellets had a melting point of 355 ℃ and a melt viscosity of 10 pas.

(Components other than liquid crystalline Polymer)

Each of the liquid crystalline polymers obtained above was mixed with the following components using a twin-screw extruder to obtain a composite resin composition. The amounts of the respective components are shown in tables 4 and 5. In the following tables, "%" represents mass%.

(B) Fibrous filler

Glass fiber 1: ECS03T-786H, a chopped fiber having a fiber diameter of 10 μm and a length of 3mm, manufactured by Nippon Denshoku K.K

Glass fiber 2: ECS03T-790DE, manufactured by Nippon Denshoku K.K., chopped fiber having a fiber diameter of 6 μm and a length of 3mm

Grinding the fibers: PF70E001 manufactured by Nindon textile Co., Ltd., fiber diameter of 10 μm, average fiber length of 70 μm (manufacturer's nominal value)

Note that the above manufacturer nominal values are different from the 100 μm in table 4, which is the actual measured value in the composition.

(C) Plate-like filler

Talc; CROWN TALC PP manufactured by Sonmura industries, Ltd., average particle diameter of 10 μm

The extrusion conditions for obtaining the composite resin composition were as follows.

[ extrusion conditions ]

[ examples 1 to 12 and comparative examples 1 to 3]

The temperature of the cylinder provided at the main feed port was set to 250 ℃ and the temperatures of the other cylinders were set to 360 ℃. The liquid crystalline polymer is supplied from the main inlet. Further, the filler was supplied from the side feed port.

[ comparative example 4]

The temperature of the cylinder provided at the main feed port was set to 250 ℃ and the temperatures of the other cylinders were set to 350 ℃. The liquid crystalline polymer is supplied from the main inlet. Further, the filler was supplied from the side feed port.

[ comparative example 5]

The temperature of the cylinder provided at the main feed port was set to 250 ℃ and the temperatures of the other cylinders were set to 380 ℃. The liquid crystalline polymer is supplied from the main inlet. Further, the filler was supplied from the side feed port.

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 composite resin composition pellets 5g were heated at 600 ℃ for 2 hours to be ashed. The ashed residue was sufficiently dispersed in a 5 mass% aqueous polyethylene glycol solution, and then transferred to a petri dish by a dropper, and the fibrous filler was observed with a microscope. Meanwhile, the weight average fiber length of the fibrous filler was measured using an image measuring instrument (LUZEXFS manufactured by Nireco Corporation).

(measurement of melt viscosity of composite resin composition)

The melt viscosity of the composite resin composition was measured at a shear rate of 1000/sec based on ISO11443 using a Capirograph model 1B manufactured by Toyo Seiki Seisaku-Sho K.K., at a temperature of 10to 30 ℃ higher than the melting point of the liquid crystalline polymer, using an orifice having an inner diameter of 1mm and a length of 20 mm. The measurement temperature was 360 ℃ for the composite resin composition using the liquid crystalline polymer 1, 350 ℃ for the composite resin composition using the liquid crystalline polymer 2, and 380 ℃ for the composite resin composition using the liquid crystalline polymer 3. The results are shown in tables 4 and 5.

The physical properties of the connector molded from the composite resin composition were measured according to the following methods. The evaluation results are shown in tables 4 and 5.

(bending test)

The composite resin composition was injection-molded under the following molding conditions to obtain a 0.8mm thick molded article, and the flexural strength, the strain at break and the flexural modulus of elasticity were measured in accordance with ASTM D790.

[ Molding conditions ]

A forming machine: sumitomo heavy machinery industry, SE100DU

Barrel temperature:

360 ℃ (examples 1 to 12 and comparative examples 1 to 3)

350 deg.C (comparative example 4)

370 deg.C (comparative example 5)

Temperature of the die: 80 deg.C

Injection speed: 33 mm/sec

(deflection temperature under load)

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

[ Molding conditions ]

A forming machine: sumitomo heavy machinery industry, SE100DU

Barrel temperature:

360 ℃ (examples 1 to 12 and comparative examples 1 to 3)

350 deg.C (comparative example 4)

370 deg.C (comparative example 5)

Temperature of the die: 80 deg.C

Injection speed: 33 mm/sec

(foaming temperature)

The composite resin composition was injection-molded under the following molding conditions to obtain a molded article of 12.5mm × 120mm × 0.8mm having a welded portion. The molded article was divided into two parts at the welded portion, and the obtained piece was set as 1 test piece and held in a hot press at a predetermined temperature for 5 minutes. Thereafter, whether or not the surface of the test piece was foamed was visually examined. The foaming temperature was set to the highest temperature at which the number of foaming occurred was zero. The predetermined temperature is set at intervals of 10 ℃ within a range of 250 to 300 ℃.

[ Molding conditions ]

A forming machine: sumitomo heavy machinery industry, SE100DU

Barrel temperature:

360 ℃ (examples 1 to 12 and comparative examples 1 to 3)

350 deg.C (comparative example 4)

370 deg.C (comparative example 5)

Temperature of the die: 90 deg.C

Injection speed: 33 mm/sec

(DDR connector warp)

The composite resin composition was injection-molded under the following molding conditions (gate: tunnel gate, gate size:

) As shown in FIG. 1, a DDR-DIMM connector having a total size of 70.0mm × 26.0mm × 4.0mmt, an inter-pitch distance of 0.6mm, and a pin hole count of 100 × 2 was obtained.

[ Molding conditions ]

A forming machine: sumitomo heavy machinery industry SE30DUZ

Barrel temperature:

360 ℃ (examples 1 to 12 and comparative examples 1 to 3)

350 deg.C (comparative example 4)

370 deg.C (comparative example 5)

Temperature of the die: 80 deg.C

Injection speed: 200 mm/sec

The resulting connector was left on a horizontal table, and the height of the connector was measured by a QuickVision 404PROCNC image measuring machine manufactured by Mitutoyo Corporation. In this case, the heights are measured at a plurality of positions indicated by black dots in fig. 2, and the difference between the maximum height and the minimum height from the least square plane is defined as the warpage of the DDR connector. The warpage was measured before and after the IR reflow under the following conditions.

[ IR reflow soldering Condition ]

A measuring machine: large desk type reflow soldering device made by Japan Pulse Laboratories, Inc. RF-300 (using far infrared heater)

Sample conveying speed: 140 mm/sec

Passing time of the reflow oven: 5 minutes

Temperature conditions in the preheating zone: 150 ℃ C

Temperature conditions of the reflow soldering zone: 190 deg.C

Peak temperature: 251 deg.C

(DDR connector deformation)

The difference in warpage before and after reflow measured by the above method was obtained as the DDR connector deformation amount.

(DDR connector minimum filling pressure)

The minimum injection filling pressure at which a good molded product can be obtained when the DDR-DIMM connector of fig. 1 is injection molded was measured as the minimum filling pressure.

[ Table 4]

[ Table 5]

As shown in tables 4 and 5, the electronic components molded from the composite resin composition of the present invention have excellent heat resistance and suppressed occurrence of warpage and blistering.

Claims

1. A composite resin composition comprising (A) a liquid crystalline polymer, (B) a fibrous filler and (C) a platy filler,

the liquid crystalline polymer (A) is a wholly aromatic polyester amide containing only the following constituent units (I) to (VI) as essential constituent components and exhibiting optical anisotropy when molten,

the fibrous filler (B) has a weight-average fiber length of 250 [ mu ] m or more,

the amount of the liquid crystalline polymer (A) is 37.5-82.5% by mass based on the entire composite resin composition,

the fibrous filler (B) is 2.5 to 17.5 mass% based on the entire composite resin composition,

the plate-like filler (C) is 15 to 45 mass% relative to the entire composite resin composition,

the total amount of the fibrous filler (B) and the plate-like filler (C) is 17.5 to 62.5 mass% based on the entire composite resin composition,

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

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

4. The composite resin composition according to claim 1 or 2, wherein the (C) plate-like filler is talc.

5. An electronic component molded from the composite resin composition according to any one of claims 1 to 4, wherein the overall length of the product is 30mm or more and the height of the product is 5mm or more.

6. The electronic component according to claim 5, which is an asymmetric electronic component having no symmetry with respect to any of an XY-axis plane, a YZ-axis plane, and an XZ-axis plane of a molded article.

7. The electronic component according to claim 5 or 6, which is a connector for a memory module having an inter-pitch distance of 0.6mm or less, a product total length of 60.0mm or more, a product height of 10.0mm or less, and a pole number of 200 poles or more.