WO2021229931A1

WO2021229931A1 - Liquid-crystalline resin composition for surface-mounted relays, and surface-mounted relay using same

Info

Publication number: WO2021229931A1
Application number: PCT/JP2021/012893
Authority: WO
Inventors: 昭宏長永; 卓馬松村
Original assignee: ポリプラスチックス株式会社
Priority date: 2020-05-13
Filing date: 2021-03-26
Publication date: 2021-11-18
Also published as: CN115551948A; KR20220158871A; JP7019110B1; JPWO2021229931A1; KR102501091B1; MY197276A; CN115551948B

Abstract

Provided are: a liquid-crystalline resin composition for surface-mounted relays, which has excellent heat resistance and air-tightness, can provide a molded article free from the deformation thereof and the detachment of a filler therefrom, and has satisfactory fluidability; and a surface-mounted relay component and a surface-mounted relay, each using the liquid-crystalline resin composition for surface-mounted relays.　The liquid-crystalline resin composition for surface-mounted relays according to the present invention comprises (A) a liquid-crystalline resin, (B) fibrous wollastonite and (C) mica, in which the liquid-crystalline resin (A) is a wholly aromatic polyester amide that contains specified amounts of structural units (I) to (VI) as essential constituent components and shows optical anisotropy when being melted, and the fibrous wollastonite (B) has an aspect ratio of 8 or more; and the surface-mounted relay is provided with a base and a terminal that protrudes from the base, and is configured such that the terminal is soldered to a printed substrate.

Description

Liquid crystal resin composition for surface mount relay and surface mount relay using it

The present invention relates to a liquid crystal resin composition for a surface mount relay and a surface mount relay using the same.

With the development of the electronics industry, the production volume of relays is steadily increasing, and there are a wide range of fields in which they are used, such as communication equipment, OA equipment, home appliances, and vending machines. Conventionally, as a relay mounted on a printed circuit board and used, an insertion mounting type (through hole type) relay is known. The through-hole relay has a terminal that protrudes vertically from the relay body, and is first mounted on one surface of the printed circuit board by inserting this terminal into a hole in the printed circuit board. Then, by soldering the terminals on the other surface of the printed circuit board, the through-hole relay is electrically conductively fixed to the printed circuit board.

In recent years, a surface mount type (surface mount type) relay has been developed as a new relay mounted on a printed circuit board and used (for example, Patent Document 1). In surface mount relays, terminals protruding vertically from the relay body are bent at right angles so that the soldering surface is parallel to the relay body. Therefore, the surface mount relay can be electrically conducted by placing the above terminals on a solder pad provided on the conductor pattern on the surface of the printed circuit board and performing a solder reflow process without providing holes in the printed circuit board. Is fixed to the printed circuit board.

Japanese Patent No. 3436310

As described above, since the surface mount relay is fixed to the printed circuit board by the solder reflow process, the molded body constituting the surface mount relay, for example, the base, the case, the bobbin, etc., is excellent so as to withstand the solder reflow process. Heat resistance is required. Further, the surface mount relay is also required to be able to maintain airtightness and shape even after the solder reflow process.

By the way, liquid crystal resin compositions are attracting attention because of their excellent heat resistance, dimensional accuracy, fluidity, and the like. However, in the liquid crystal resin composition, there may be a problem that the filler protrudes from the surface of the molded product of the composition and further desorbs to cause a functional disorder such as poor continuity of the product. Further, when a liquid crystal resin composition is molded to obtain a molded body constituting a surface mount relay, the liquid crystal resin composition is required to have good fluidity.

The present invention has been made in view of such circumstances, and is a liquid crystal property for surface mount relays having excellent heat resistance and airtightness, providing a molded body in which deformation and desorption of filler are suppressed, and having good fluidity. It is an object of the present invention to provide a resin composition, a surface mount relay component made of the composition, and a surface mount relay including the component.

The present inventors combine a liquid crystal resin containing a specific structural unit in a predetermined amount with a predetermined content, fibrous wollastonite, and mica, and set the aspect ratio of the fibrous wollastonite in a predetermined range. It was found that the above problem can be solved by doing so. Specifically, the present invention provides the following.

(1) A liquid crystal resin composition for a surface mount relay containing (A) a liquid crystal resin, (B) fibrous wollastonite, and (C) mica.
The liquid crystal resin (A) is composed of the following structural units (I) to (VI) as essential constituents.
The content of the constituent unit (I) is 50 to 70 mol% with respect to all the constituent units.
The content of the constituent unit (II) is 0.5 mol% or more and less than 4.5 mol% with respect to all the constituent units.
The content of the constituent unit (III) is 10.25 to 22.25 mol% with respect to all the constituent units.
The content of the constituent unit (IV) is 0.5 mol% or more and less than 4.5 mol% with respect to all the constituent units.
The content of the constituent unit (V) is 5.75 to 23.75 mol% with respect to all the constituent units.
The content of the constituent unit (VI) is 1 to 7 mol% with respect to all the constituent units.
The total content of the constituent unit (II) and the constituent unit (IV) with respect to all the constituent units is 1 mol% or more and less than 5 mol%.
The total content of the constituent units (I) to (VI) is 100 mol% with respect to all the constituent units.
A total aromatic polyesteramide exhibiting optical anisotropy when melted, wherein the molar ratio of the structural unit (VI) to the total of the structural unit (V) and the structural unit (VI) is 0.04 to 0.37. ,
The aspect ratio of the fibrous wollastonite (B) is 8 or more.
For the entire liquid crystal resin composition,
The content of the liquid crystal resin (A) is 55 to 75% by mass.
The content of the fibrous wollastonite (B) is 2.5 to 17.5% by mass.
The content of (C) mica is 15 to 32.5% by mass,
The total content of the (B) fibrous wollastonite and the (C) mica is 25 to 45% by mass.
And
The surface mount relay is a liquid crystal resin composition which is a surface mount relay having a base and terminals protruding from the base, and the terminals are soldered to a printed circuit board.

(2) The total number of moles of the constituent unit (III) and the constituent unit (IV) is 1 to 1.1 times the total number of moles of the constituent unit (V) and the constituent unit (VI), or The description in (1), wherein 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). Liquid crystal resin composition.

(3) A surface mount relay component made of the composition according to (1) or (2).

(4) A surface mount relay equipped with the parts described in (3).

According to the present invention, the composition comprises a liquid crystal resin composition for a surface mount relay having excellent heat resistance and airtightness, providing a molded body in which deformation and desorption of a filler are suppressed, and having good fluidity. A component for a surface mount relay and a surface mount relay including the component can be provided.

1 (a) is a perspective view schematically showing an embodiment of a surface mount relay according to the present invention, and FIG. 1 (b) is a partial cross-sectional view showing an AA cross section of FIG. 1 (a). 2 (a) and 2 (b) are side views schematically showing a state in which the embodiment of the surface mount relay according to the present invention is mounted on a printed circuit board. 3A is a plan view showing a relay case molded in an embodiment, and FIG. 3B is a partial vertical sectional view showing a BB cross section of FIG. 3A. Unless otherwise specified, the unit of the numerical value in the figure is mm (hereinafter, the same applies to FIGS. 4 (a) to 5 (b)). 4 (a) is a plan view showing a pedestal mounted from the bottom surface side of the relay case shown in FIGS. 3 (a) and 3 (b), and FIG. 4 (b) is a plan view of FIG. 4 (a). It is a partial vertical sectional view which shows the CC cross section. FIG. 5A shows a relay case in which the pedestal shown in FIGS. 4A and 4B is attached and the inside is sealed in order to evaluate the swelling during reflow of the relay case and the airtightness of the relay case in the embodiment. It is a partial vertical sectional view showing. FIG. 5B is a diagram showing measurement points in the evaluation of swelling during reflow of the relay case performed in the embodiment. Specifically, FIG. 5B is a plan view showing a relay case as in FIG. 3A, and a plurality of positions indicated by black circles are measurement points.

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

<Liquid crystal resin composition for surface mount relay>
The liquid crystal resin composition for a surface mount relay according to the present invention contains a specific liquid crystal resin, fibrous wollastonite, and mica in predetermined amounts, and the aspect ratio of the fibrous wollastonite is 8 or more. The surface mount relay is a surface mount relay having a base and terminals protruding from the base, and the terminals are soldered to a printed circuit board. Hereinafter, the components constituting the liquid crystal resin composition according to the present invention will be described.

[Liquid crystal resin]
The liquid crystal resin composition according to the present invention contains the liquid crystal resin which is the above-mentioned total aromatic polyester amide. Since the total aromatic polyester amide has a low melting point, the processing temperature can be lowered and the generation of decomposition gas at the time of melting is suppressed. The liquid crystal resin can be used alone or in combination of two or more.

The total aromatic polyesteramide in the present invention has 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 ( It consists of VI).

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

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

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

The structural unit (IV) is derived from 1,3-phenylenedicarboxylic acid (hereinafter, also referred to as "IA"). The total aromatic polyesteramide in the present invention contains 0.5 mol% or more and less than 4.5 mol% of the constituent unit (IV) with respect to all the constituent units. When the content of the structural unit (IV) is less than 0.5 mol% or 4.5 mol% or more, at least one of low melting point and heat resistance tends to be insufficient. From the viewpoint of achieving both a low melting point and heat resistance, the content of the structural unit (IV) is preferably 0.5 to 3.75 mol%, more preferably 0.5 to 3 mol%.

The structural unit (V) is derived from 4,4'-dihydroxybiphenyl (hereinafter, also referred to as "BP"). The total aromatic polyester amide in the present invention contains 5.75 to 23.75 mol% of the structural unit (V) with respect to all the structural units. When the content of the structural unit (V) is less than 5.75 mol% or more than 23.75 mol%, at least one of low melting point and heat resistance tends to be insufficient. From the viewpoint of achieving both a low melting point and heat resistance, the content of the structural unit (V) is preferably 8.5 to 20.375 mol%, more preferably 11.25 to 17 mol% (for example, 11. 675 to 17 mol%).

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

The total aromatic polyesteramide in the present invention contains 1 mol% or more and less than 5 mol% of the total of the constituent units (II) and the constituent units (IV) with respect to all the constituent units. In the above-mentioned total aromatic polyester amide, the flexible structural unit (II) having a naphthalene skeleton and the flexible structural unit (IV) having a benzene skeleton coexist in the total amount in the above range to lower the melting point. It is easy to achieve both heat resistance and heat resistance. If the total content is less than 1 mol%, the proportion of the flexible constituent units becomes too small, so that the melting point tends to be insufficient. When the total content is 5 mol% or more, the ratio of the flexible constituent units becomes too large, so that the heat resistance tends to be insufficient. From the viewpoint of achieving both a 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 total aromatic polyester amide in the present invention, the molar ratio of the constituent unit (VI) to the total of the constituent units (V) and the constituent units (VI) is 0.04 to 0.37. When the molar ratio is less than 0.04, the proportion of the constituent units having a biphenyl skeleton increases, so that the crystallinity of the total aromatic polyesteramide becomes low, and the compatibility between the low melting point and the heat resistance becomes insufficient. Cheap. Further, when the molar ratio exceeds 0.37, heterogeneous bonds other than ester bonds increase, so that the crystallinity of the total aromatic polyesteramide becomes low, and it tends to be insufficient to achieve both low melting point and heat resistance. .. From the viewpoint of achieving both a low melting point and heat resistance, the molar ratio is 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 total number of moles of the structural unit (III) and the structural unit (IV) (hereinafter, also referred to as “mol number 1A”) is referred to as the structural unit (V). It is 1 to 1.1 times the total number of moles with the structural unit (VI) (hereinafter, also referred to as "molar number 2A"), or the number of moles 2A is 1 to 1.1 times the number of moles 1A. Is preferable. It is more preferable that the number of moles 1A is 1.02 to 1.06 times the number of moles 2A, or the number of moles 2A is 1.02 to 1.06 times the number of moles 1A. It is even more preferable that the number of moles 1A is 1.024 to 1.056 times the number of moles 2A, or the number of moles 2A is 1.024 to 1.056 times the number of moles 1A.

As described above, in the total aromatic polyesteramide in the present invention, each of the specific constituent units (I) to (VI) and the total of the constituent units (II) and the constituent units (IV) is converted into all the constituent units. On the other hand, since it contains a specific amount and the molar ratio of the structural unit (VI) to the total of the structural unit (V) and the structural unit (VI) is within a specific range, both low melting point and heat resistance are compatible. Is enough. The total aromatic polyesteramide of the present invention contains 100 mol% of the constituent units (I) to (VI) in total with respect to all the constituent units.

Next, the method for producing the total aromatic polyester amide in the present invention will be described. The total aromatic polyester amide in the present invention is polymerized by using a direct polymerization method, a transesterification method, or the like. In the polymerization, a melt polymerization method, a solution polymerization method, a slurry polymerization method, a solid phase polymerization method, etc., or a combination of two or more of these is used, and a melt polymerization method or a combination of the melt polymerization method and the solid phase polymerization method is used. Is preferably used.

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

Various catalysts can be used for these polymerizations, and typical ones are potassium acetate, magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, antimony trioxide, and tris (2). , 4-Pentandionato) Metal salt-based catalysts such as cobalt (III) and organic compound-based catalysts such as 1-methylimidazole and 4-dimethylaminopyridine can be mentioned.

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

In the reaction, all raw material monomers (HBA, HNA, TA, IA, BP, and APAP), an acylating agent, and a catalyst can be charged in the same reaction vessel to initiate the reaction (one-stage method), or the raw material monomer HBA. , HNA, BP, and APAP can be acylated with an acylating agent and then reacted with the carboxyl groups of TA and IA (two-stage method).

After the inside of the reaction system reaches a predetermined temperature, melt polymerization is carried out by starting depressurization to a predetermined decompression degree. After the torque of the stirrer reaches a predetermined value, an inert gas is introduced, and the pressure is changed from a reduced pressure state to a normal pressure state to a predetermined pressure state, and the total aromatic polyesteramide is discharged from the reaction system.

The total aromatic polyesteramide produced by the above polymerization method can further increase its molecular weight by solid-phase polymerization in which it is heated under normal pressure, reduced pressure, or in an inert gas. Preferred conditions for the solid phase polymerization reaction are a reaction temperature of 230 to 350 ° C., preferably 260 to 330 ° C., and a final ultimate pressure of 10 to 760 Torr (that is, 1,330 to 101,080 Pa).

Next, the properties of the total aromatic polyester amide will be described. The total aromatic polyesteramide in the present invention exhibits optical anisotropy when melted. Exhibiting optical anisotropy when melted means that the total aromatic polyesteramide in the present invention is a liquid crystal resin.

In the present invention, the fact that the total aromatic polyester amide is a liquid crystal resin is an indispensable element for the total aromatic polyester amide to have both thermal stability and easy processability. The total aromatic polyesteramide composed of the constituent units (I) to (VI) may not form an anisotropic molten phase depending on the constituent components and the sequence distribution in the polymer, but the liquid crystal in the present invention. The sex resin is limited to all aromatic polyesteramides that exhibit optical anisotropy when melted.

The nature of melt anisotropy can be confirmed by a conventional polarization inspection method using an orthogonal polarizing element. More specifically, the confirmation of melt anisotropy can be carried out by melting a sample placed on a hot stage manufactured by Rinkamu using a polarizing microscope manufactured by Olympus and observing it at a magnification of 150 times in a nitrogen atmosphere. The liquid crystalline resin is optically anisotropic and transmits light when inserted between orthogonal polarizing elements. If the sample is optically anisotropic, polarized light is transmitted even in a molten static liquid state, for example.

Since a nematic liquid crystal resin causes a significant decrease in viscosity above the melting point, generally, showing liquid crystallinity at a temperature above the melting point is an index of processability. It is preferable that the melting point is as high as possible from the viewpoint of heat resistance, but it is preferable that the melting point is 360 ° C. or lower in consideration of thermal deterioration during melt processing of the liquid crystal resin and the heating capacity of the molding machine. .. It is more preferably 300 to 360 ° C, and even more preferably 340 to 358 ° C.

The melt viscosity of the total aromatic polyesteramide at a temperature 10 to 30 ° C. higher than the melting point of the total aromatic polyesteramide in the present invention and a shear rate of 1000 / sec is preferably 500 Pa · s or less, more preferably 0. It is .5 to 300 Pa · s, and even more preferably 1 to 100 Pa · s. When the melt viscosity is within the above range, the total aromatic polyester amide itself or the composition containing the total aromatic polyester amide tends to secure fluidity at the time of molding, and the filling pressure is excessive. It is hard to become. In addition, in this specification, the melt viscosity means the melt viscosity measured in accordance with ISO11443.

The liquid crystal resin composition according to the present invention contains the above liquid crystal resin in an amount of 55 to 75% by mass based on the entire liquid crystal resin composition. When the content of the liquid crystal resin is less than 55% by mass with respect to the entire liquid crystal resin composition, the fluidity of the liquid crystal resin composition tends to deteriorate, and the surface mount relay obtained from the liquid crystal resin composition is likely to deteriorate. It is not preferable because the airtightness of the molded body such as parts may decrease. When the content of the liquid crystal resin is more than 75% by mass with respect to the entire liquid crystal resin composition, the effect of suppressing deformation of the molded body such as the surface mount relay component obtained from the liquid crystal resin composition, the airtightness, etc. It is not preferable because at least one of the above may decrease. The liquid crystal resin composition according to the present invention preferably contains the above liquid crystal resin in an amount of 57.5 to 72.5% by mass, more preferably 60 to 70% by mass, based on the entire liquid crystal resin composition. preferable.

[(B) Fibrous Wollastonite]
(B) The aspect ratio of the fibrous wollastonite, that is, the value of the average fiber length / average fiber diameter is 8 or more. The aspect ratio is preferably 10 to 25, more preferably 15 to 20, from the viewpoint of the effect of suppressing deformation of a molded body such as a surface mount relay component obtained from the liquid crystal resin composition according to the present invention. be.

(B) The fibrous wollastonite is not particularly limited, and for example, a known fibrous wollastonite can be used. (B) The fibrous wollastonite may be used alone or in combination of two or more having different aspect ratios, average fiber lengths, average fiber diameters and the like.

(B) The average fiber diameter of the fibrous wollastonite is preferably 3.0 to 50 μm, and the more preferable average fiber diameter is 4.5 to 40 μm. When the average fiber diameter is 3.0 μm or more, a molded product such as a surface mount relay component obtained from the liquid crystal resin composition according to the present invention tends to have sufficient mechanical strength and deflection temperature under load. When the average fiber diameter is 50 μm or less, the effect of suppressing raising of the surface of the molded product tends to be high. In the present specification, the average fiber diameter of (B) fibrous wollastonite in the liquid crystal resin composition is the fibrous state remaining after the liquid crystal resin composition is incinerated by heating at 600 ° C. for 2 hours. The wollastonite is observed with a scanning electron microscope, and the average of the measured fiber diameters of 100 fibrous wollastonite is adopted.

(B) The average fiber length of the fibrous wollastonite is preferably 30 to 800 μm, and the more preferable average fiber length is 50 to 600 μm. When the average fiber length is 30 μm or more, a molded product such as a surface mount relay component obtained from the liquid crystal resin composition according to the present invention tends to have sufficient mechanical strength and deflection temperature under load. When the average fiber length is 800 μm or less, the effect of suppressing raising of the surface of the molded product tends to be high. In the present specification, the average fiber length of (B) fibrous wollastonite in the liquid crystal resin composition is the fibrous state remaining after the liquid crystal resin composition is incinerated by heating at 600 ° C. for 2 hours. 10 fibrous wollastonite images were taken from a CCD camera to a PC, and 100 fibrous wollastonites were taken for each stereoscopic microscopic image by an image processing method using an image measuring machine, that is, a total of 1000 fibrous images. The average of the measured fiber lengths for wollastonite is used.

The liquid crystal resin composition according to the present invention contains (B) fibrous wollastonite in an amount of 2.5 to 17.5% by mass based on the entire liquid crystal resin composition. (B) When the content of the fibrous wollastonite is less than 2.5% by mass with respect to the entire liquid crystal resin composition, the molded product such as a surface mount relay component obtained from the liquid crystal resin composition It is not preferable because the airtightness may decrease. (B) When the content of the fibrous wollastonite is more than 17.5% by mass with respect to the entire liquid crystal resin composition, the molded product such as a surface mount relay component obtained from the liquid crystal resin composition It is not preferable because the deformation suppressing effect may be reduced. The fibrous wollastonite (B) in the present invention is preferably contained in the liquid crystal resin composition in an amount of 3.5 to 14% by mass, preferably 5 to 10% by mass, based on the entire liquid crystal resin composition. Is more preferable.

[(C) Mica]
The liquid crystal resin composition according to the present invention contains mica. By containing mica in the liquid crystal resin composition according to the present invention, the fluidity of the liquid crystal resin composition can be easily improved, and a molded product in which deformation is suppressed can be obtained. Mica can be used alone or in combination of two or more.

Mica is contained in an amount of 15 to 32.5% by mass based on the entire liquid crystal resin composition. If the content of mica is less than 15% by mass with respect to the entire liquid crystal resin composition, it is not preferable because the deformation of the molded product obtained from the liquid crystal resin composition is not sufficiently suppressed. When the content of mica is more than 32.5% by mass with respect to the entire liquid crystal resin composition, the fluidity of the liquid crystal resin composition tends to deteriorate, and molding of the liquid crystal resin composition may become difficult. It is not preferable because it has a property and may reduce the airtightness of a molded product such as a surface-mounted relay component obtained from a liquid crystal resin composition. Mica is preferably contained in the liquid crystal resin composition in an amount of 17 to 31.5% by mass, more preferably 20 to 30% by mass, based on the entire liquid crystal resin composition.

[Mica]
Mica is a pulverized silicate mineral containing aluminum, potassium, magnesium, sodium, iron and the like. Examples of mica that can be used in the present invention include muscovite, phlogopite, biotite, artificial mica, and the like, and among these, muscovite is preferable in that it has a good hue and is inexpensive.

Further, in the production of mica, a wet pulverization method and a dry pulverization method are known as methods for pulverizing minerals. The wet pulverization method is a method in which rough mica is roughly pulverized by a dry pulverizer, water is added, and the main pulverization is performed by wet pulverization in a slurry state, followed by dehydration and drying. Although the dry pulverization method is a low-cost and general method as compared with the wet pulverization method, it is easier to pulverize the mineral thinly and finely by using the wet pulverization method. It is preferable to use a thin and fine pulverized product in the present invention because mica having a preferable average particle size and thickness described later can be obtained. Therefore, in the present invention, it is preferable to use mica produced by the wet pulverization method.

Further, since the wet pulverization method requires a step of dispersing the object to be crushed in water, a coagulation sedimentation agent and / or a sedimentation aid is added to the object to be pulverized in order to improve the dispersion efficiency of the object to be pulverized. Is common. Examples of the coagulation sedimenting agent and the sedimentation aid that can be used in the present invention include polyaluminum chloride, aluminum sulfate, ferrous sulfate, ferric sulfate, copper chloride, polyiron sulfate, ferric chloride, and iron-silica inorganic high. Examples thereof include ferric chloride-silica inorganic polymer flocculants, slaked lime (Ca (OH) ₂ ), caustic soda (NaOH), soda ash (Na ₂ CO ₃ ) and the like. These coagulation sedimentation agents and sedimentation aids have an alkaline or acidic pH. The mica used in the present invention preferably does not use a coagulation sedimentation agent and / or a sedimentation aid during wet pulverization. When mica that has not been treated with the coagulation sedimentation agent and / or the sedimentation aid is used, the liquid crystal resin in the liquid crystal resin composition is less likely to be decomposed, and a large amount of gas is less likely to be generated or the molecular weight of the liquid crystal resin is less likely to decrease. Therefore, it is easy to maintain better performance of the obtained molded body such as a surface mount relay component.

The mica that can be used in the present invention preferably has an average particle size of 10 to 100 μm measured by a microtrack laser diffraction method, and particularly preferably an average particle size of 20 to 80 μm. When the average particle size of mica is 10 μm or more, the effect of improving the rigidity of the molded product is likely to be sufficient, which is preferable. When the average particle size of mica is 100 μm or less, the rigidity of the molded product is likely to be sufficiently improved, and the weld strength is also likely to be sufficient, which is preferable. Further, when the average particle size of mica is 100 μm or less, it is easy to secure sufficient fluidity for molding the surface mount relay component of the present invention.

The thickness of 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 measured by observation with an electron microscope. When the thickness of the mica is 0.01 μm or more, the mica is less likely to crack during the melt processing of the liquid crystal resin composition, and the rigidity of the molded product 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 product is likely to be sufficient, which is preferable.

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

In the liquid crystal resin composition according to the present invention, the total content of (B) fibrous wollastonite and (C) mica is 25 to 45% by mass with respect to the entire liquid crystal resin composition. When the content is less than 25% by mass with respect to the entire liquid crystal resin composition, at least one of the effect of suppressing deformation of the molded body such as the surface mount relay component obtained from the liquid crystal resin composition, the airtightness, and the like. It is not preferable because there is a risk that the liquid crystal will drop. When the content is more than 45% by mass with respect to the entire liquid crystal resin composition, the fluidity of the liquid crystal resin composition tends to deteriorate, and the surface mount relay component obtained from the liquid crystal resin composition This is not preferable because the airtightness of the molded product may decrease. The content is preferably 27.5 to 37.5% by mass, more preferably 30 to 40% by mass, based on the entire liquid crystal resin composition.

[Other ingredients]
The liquid crystal resin composition according to the present invention includes other polymers, other fillers, and known substances generally added to synthetic resins, that is, antioxidants and ultraviolet rays, as long as the effects of the present invention are not impaired. Stabilizers such as absorbents, antistatic agents, flame retardants, colorants such as dyes and pigments, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents and other other components are also added as appropriate according to the required performance. be able to. Other components may be used alone or in combination of two or more.

Examples of other polymers include liquid crystal resins other than (A) liquid crystal resin. However, it is preferable that the liquid crystal resin composition according to the present invention does not contain a liquid crystal resin other than (A) the liquid crystal resin, from at least any one of the deformation suppressing effect of the molded body and the airtightness. Examples of other polymers include epoxy group-containing copolymers. However, the liquid crystal resin composition according to the present invention is less likely to generate gas due to thermal decomposition of the epoxy group-containing copolymer and to cause the molded product such as a surface-mounted relay component to swell. Is preferably free of epoxy group-containing copolymers.

The other filler means a filler other than fibrous talc talc having an aspect ratio of 8 or more, mica, and carbon black, and for example, a fibrous filler other than fibrous talc talc having an aspect ratio of 8 or more (for example). , Fibrous wollastonite with an aspect ratio of less than 8 and milled fiber), and plate-like fillers other than mica (for example, talc). However, from the viewpoints of the fluidity of the liquid crystal resin composition, the effect of suppressing deformation of the molded product, the effect of suppressing filler detachment, etc., the liquid crystal resin composition according to the present invention is a fibrous wollastonite having an aspect ratio of less than 8. It is preferable that it does not contain milled fiber and talc.

The method for producing a liquid crystal resin composition according to the present invention is not particularly limited as long as the components in the liquid crystal resin composition can be uniformly mixed, and can be appropriately selected from the conventionally known methods for producing a resin composition. For example, each component is melt-kneaded and extruded using a melt-kneading device such as a single-screw or twin-screw extruder, and then the obtained liquid crystal resin composition is processed into a desired form such as powder, flakes, and pellets. There is a way to do it.

Since the liquid crystal resin composition according to the present invention has excellent fluidity, the minimum filling pressure at the time of molding is unlikely to be excessive, and parts for surface mount relays and the like can be preferably molded.

The melt viscosity of the liquid crystal resin composition measured according to ISO11443 at a temperature 10 to 30 ° C. higher than the melting point of the liquid crystal resin at a shear rate of 1000 / sec is 500 Pa · s or less (more preferably 5 Pa · s or more). It is preferable that the temperature is 100 Pa · s or less) because it is easy to secure the fluidity of the liquid crystal resin composition and the filling pressure is unlikely to become excessive at the time of molding the surface-mounted relay component.

<Surface mount relay parts and surface mount relays>
By molding the liquid crystal resin composition according to the present invention, the surface mount relay component according to the present invention can be obtained. The surface mount relay component according to the present invention is excellent in heat resistance and airtightness, and deformation and desorption of filler are suppressed. Since the surface mount relay according to the present invention includes the above parts, it can (1) have excellent heat resistance and can withstand solder reflow processing, and (2) can maintain airtightness and shape even after solder reflow processing. , (3) Desorption of filler is suppressed, and functional disorders such as poor continuity are less likely to occur.

The surface mount relay component according to the present invention and the surface mount relay according to the present invention will be described. 1 (a) is a perspective view schematically showing an embodiment of a surface mount relay according to the present invention, and FIG. 1 (b) is a partial cross-sectional view showing an AA cross section of FIG. 1 (a). The surface mount relay 1 includes a base 2, a case 3, a coil block 4, a polaron block 5, and a terminal 6.

The base 2 includes a terminal 6 protruding from the base 2. The case 3 is arranged on the outer peripheral portion of the upper surface of the base 2. The coil block 4 and the polaron block 5 are arranged in this order in the central portion of the upper surface of the base 2.

The case 3 is arranged so as to cover the outer peripheral portion of the upper surface of the base 2 and the coil block 4 and the polaron block 5. The coil block 4 and the tangent block 5 are housed in a hollow container-shaped space formed by the base 2 and the case 3.

The coil block 4 includes a bobbin 41, a coil 42, and an iron core 43, and is arranged at the center of the upper surface of the base 2. The bobbin 41 has a cylindrical portion penetrating in the long axis direction, and a coil 42 electrically connected to one end of a part of the terminal 6 is wound around the outer circumference of the bobbin 41, and the cylindrical portion of the bobbin 41 is wound. The iron core 43 is inserted in the.

The polaron block 5 includes a polaron connecting portion 51 and a polaron 52 extending from the polaron connecting portion 51 in the opposite directions along the long axis direction of the bobbin 41, and is arranged on the coil block 4. The polaron 52 is electrically connected to one end of another portion of the terminal 6. When an electromagnet is formed by conduction to the coil 42, the tip of the quadrupole 52 moves toward the coil block 4 due to the magnetic force. As a result, the signal from the input side including the coil 42 is transmitted to the output side including the polaron 52.

One end of the terminal 6 is electrically connected to the coil 42 or the polaron 52, and the other end is electrically conductively connected to the printed circuit board 7 described later. The terminal 6 protrudes from the base 2 and is soldered to the printed circuit board 7 as described later.

Among the above-mentioned parts, the base 2, the case 3, and the bobbin 41 are related to the present invention in consideration of the fact that they are excellent in heat resistance and airtightness and can be formed as a molded body in which deformation and desorption of filler are suppressed. It is preferably composed of a liquid crystal resin composition. That is, examples of the surface mount relay component according to the present invention include a base, a case, and a bobbin.

In the surface mount relay 1, for example, the coil block 4 and the polaron block 5 are arranged in this order in the central portion of the upper surface of the base 2, and then the case 3 is arranged on the outer peripheral portion of the upper surface of the base 2, and the base 2 and the case are arranged. It can be manufactured by adhering 3 and 3 with an adhesive.

The method of mounting the surface mount relay 1 on the printed circuit board 7 will be described. As shown in FIG. 2A, in the surface mount relay 1, the terminal 6 protruding vertically from the surface mount relay 1 is bent at a right angle so that the soldering surface is parallel to the surface mount relay 1. Therefore, in the surface mount relay 1, the terminal 6 is placed on a solder pad (not shown) provided on the conductor pattern 8 on the surface of the printed circuit board 7 without providing a hole in the printed circuit board 7, and the solder reflow process is performed. By doing so, it is electrically conductively fixed to the printed circuit board 7.

In the above description, as shown in FIG. 2A, the case where the tip of the terminal 6 protruding vertically from the surface mount relay 1 is bent at a right angle to the outside of the surface mount relay 1 is shown. On the other hand, as shown in FIG. 2B, the tip of the terminal 6 protruding vertically from the surface mount relay 1 may be bent at a right angle to the inside of the surface mount relay 1.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.

<Examples 1 to 3 and Comparative Examples 1 to 11>
In the following Examples and Comparative Examples, the liquid crystal resins LCP1 to LCP4 were manufactured as follows. At that time, the melting point and the melt viscosity of the pellets were measured under the following conditions.

[Measurement of melting point]
After measuring the heat absorption peak temperature (Tm1) observed when the liquid crystal resin is heated from room temperature to 20 ° C./min with a DSC manufactured by TA Instruments, it is 2 at a temperature of (Tm1 + 40) ° C. After holding for 1 minute, the temperature of the heat absorption peak observed when the temperature was once cooled to room temperature under the condition of lowering temperature of 20 ° C./min and then heated again under the condition of raising temperature of 20 ° C./min was measured.

[Measurement of melt viscosity]
Using Capillograph 1B type manufactured by Toyo Seiki Seisakusho Co., Ltd., using an orifice with an inner diameter of 1 mm and a length of 20 mm at a temperature 10 to 30 ° C higher than the melting point of the liquid crystal resin, to ISO11443 at a shear rate of 1000 / sec. According to this, the melt viscosity of the liquid crystal resin was measured. The measured temperature was 360 ° C. for LCP1, 350 ° C. for LCP2, 380 ° C. for LCP3, and 380 ° C. for LCP4.

(Manufacturing method of LCP1)
The following raw material monomers, fatty acid metal salt catalysts, and acylating agents were charged into a polymerization vessel equipped with a stirrer, a reflux column, a monomer inlet, a nitrogen inlet, and a depressurization / outflow line, and nitrogen substitution was started.
(I) 4-Hydroxybenzoic acid: 1385 g (60 mol%) (HBA)
(II) 6-Hydroxy-2-naphthoic acid: 88 g (2.8 mol%) (HNA)
(III) 1,4-phenylenedicarboxylic acid: 504 g (18.15 mol%) (TA)
(IV) 1,3-phenylenedicarboxylic acid: 19 g (0.7 mol%) (IA)
(V) 4,4'-Dihydroxybiphenyl: 415 g (13.35 mol%) (BP)
(VI) N-Acetyl-p-Aminophenol: 126 g (5 mol%) (APAP)
Potassium acetate catalyst: 120 mg
Acetic anhydride: 1662 g
After charging the raw materials 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. Then, the temperature is further raised to 360 ° C. over 5.5 hours, and then the pressure is reduced to 10 Torr (that is, 1330 Pa) over 20 minutes while distilling acetic acid, excess acetic anhydride, and other low boiling points. Melt polymerization was performed. After the stirring torque reached a predetermined value, nitrogen was introduced to bring the polymer into a pressurized state from a reduced pressure state through a normal pressure state, the polymer was discharged from the lower part of the polymerization vessel, and the strands were pelletized and pelletized. The obtained pellet had a melting point of 345 ° C. and a melt viscosity of 10 Pa · s.

(Manufacturing method of LCP2)
The following raw material monomers, fatty acid metal salt catalysts, and acylating agents were charged into a polymerization vessel equipped with a stirrer, a reflux column, a monomer inlet, a nitrogen inlet, and a depressurization / outflow line, and nitrogen substitution was started.
(I) 4-Hydroxybenzoic acid 1380 g (60 mol%) (HBA)
(II) 157 g (5 mol%) of 6-hydroxy-2-naphthoic acid (HNA)
(III) 484 g (17.5 mol%) of 1,4-phenylenedicarboxylic acid (TA)
(V) 4,4'-Dihydroxybiphenyl 388 g (12.5 mol%) (BP)
(VI) N-Acetyl-p-Aminophenol 126 g (5 mol%) (APAP)
Potassium acetate catalyst 110 mg
Acetic anhydride 1659g
After charging the raw materials 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. Then, the temperature is further raised to 340 ° C. over 4.5 hours, and then the pressure is reduced to 10 Torr (that is, 1330 Pa) over 15 minutes while distilling acetic acid, excess acetic anhydride, and other low boiling points. Melt polymerization was performed. After the stirring torque reached a predetermined value, nitrogen was introduced to bring the polymer into a pressurized state from a reduced pressure state through a normal pressure state, the polymer was discharged from the lower part of the polymerization vessel, and the strands were pelletized and pelletized. The obtained pellet had a melting point of 336 ° C. and a melt viscosity of 20 Pa · s.

(Manufacturing method of LCP3)
The following raw material monomers, fatty acid metal salt catalysts, and acylating agents were charged into a polymerization vessel equipped with a stirrer, a reflux column, a monomer inlet, a nitrogen inlet, and a depressurization / outflow line, and nitrogen substitution was started.
(I) 4-Hydroxybenzoic acid: 1040 g (48 mol%) (HBA)
(II) 6-Hydroxy-2-naphthoic acid: 89 g (3 mol%) (HNA)
(III) 1,4-phenylenedicarboxylic acid: 547 g (21 mol%) (TA)
(IV) 1,3-phenylenedicarboxylic acid: 91 g (3.5 mol%) (IA)
(V) 4,4'-Dihydroxybiphenyl: 716 g (24.5 mol%) (BP)
Potassium acetate catalyst: 110 mg
Acetic anhydride: 1644 g

After charging the raw materials in 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. Then, the temperature is further raised to 360 ° C. over 5.5 hours, and then the pressure is reduced to 5 Torr (that is, 667 Pa) over 20 minutes while distilling acetic acid, excess acetic anhydride, and other low boiling points. Melt polymerization was performed. After the stirring torque reached a predetermined value, nitrogen was introduced to bring the polymer into a pressurized state from a reduced pressure state through a normal pressure state, the polymer was discharged from the lower part of the polymerization vessel, and the strands were pelletized and pelletized. The obtained pellet had a melting point of 355 ° C. and a melt viscosity of 10 Pa · s.

(Manufacturing method of LCP4)
The following raw material monomers, fatty acid metal salt catalysts, and acylating agents were charged into a polymerization vessel equipped with a stirrer, a reflux column, a monomer inlet, a nitrogen inlet, and a depressurization / outflow line, and nitrogen substitution was started.
(I) 4-Hydroxybenzoic acid: 37 g (2 mol%) (HBA)
(II) 6-Hydroxy-2-naphthoic acid: 1218 g (48 mol%) (HNA)
(III) 1,4-phenylenedicarboxylic acid: 560 g (25 mol%) (TA)
(V) 4,4'-Dihydroxybiphenyl: 628 g (25 mol%) (BP)
Potassium acetate catalyst: 165 mg
Acetic anhydride: 1432 g
After charging the raw materials 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. Then, the temperature is further raised to 360 ° C. over 5.5 hours, and then the pressure is reduced to 5 Torr (that is, 667 Pa) over 30 minutes while distilling acetic acid, excess acetic anhydride, and other low boiling points. Melt polymerization was performed. After the stirring torque reached a predetermined value, nitrogen was introduced to bring the polymer into a pressurized state from a reduced pressure state through a normal pressure state, the polymer was discharged from the lower part of the polymerization vessel, and the strands were pelletized and pelletized. The obtained pellets were heat-treated at 300 ° C. for 3 hours under a nitrogen stream. The melting point of the pellet was 348 ° C., and the melt viscosity was 9 Pa · s.

(Ingredients other than liquid crystal resin)
Fibrous filler Fibrous wollastonite 1: NYGLOS 8 (manufactured by NYCO Materials, aspect ratio 17, average fiber length 136 μm, average fiber diameter 8 μm)
Fibrous wollastonite 2: NYAD 325 (manufactured by NYCO Materials, aspect ratio 5, average fiber length 50 μm, average fiber diameter 5 μm)
Mild fiber: PF70E001 manufactured by Nitto Boseki Co., Ltd., fiber diameter 10 μm, average fiber length 70 μm (manufacturer's nominal value)
Glass fiber: ECS03T-786H manufactured by Nippon Electric Glass Co., Ltd., chopped strand / plate-shaped filler mica with fiber diameter 10 μm and length 3 mm; AB-25S manufactured by Yamaguchi Mica Industry Co., Ltd., average particle diameter 25 μm
Talc; Crown Talc PP manufactured by Matsumura Sangyo Co., Ltd., average particle size 10 μm

Each liquid crystal resin obtained above and a component other than the liquid crystal resin described above were mixed using a twin-screw extruder to obtain a liquid crystal resin composition. The blending amount of each component is as shown in Tables 1 and 2. In the following, "%" regarding the blending amount in the table indicates mass%. The extrusion conditions for obtaining the liquid crystal resin composition are as follows.
[Extrusion conditions]
The temperature of the cylinder provided in the main feed port was 250 ° C., and the temperatures of the other cylinders were all as follows. All liquid crystal resin was supplied from the main feed port. The filler was supplied from the side feed port.
Other cylinder temperature:
360 ° C (Examples 1 to 3 and Comparative Examples 1 to 7 and 11)
350 ° C (Comparative Example 8)
370 ° C (Comparative Examples 9 and 10)

(Measurement of melt viscosity of liquid crystal resin composition)
Using Capillograph 1B type manufactured by Toyo Seiki Seisakusho Co., Ltd., using an orifice with an inner diameter of 1 mm and a length of 20 mm at a temperature 10 to 30 ° C higher than the melting point of the liquid crystal resin, to ISO11443 at a shear rate of 1000 / sec. According to this, the melt viscosity of the liquid crystal resin composition was measured. The measurement temperature was 360 ° C. for the liquid crystal resin composition using LCP1, 350 ° C. for the liquid crystal resin composition using LCP2, 380 ° C. for the liquid crystal resin composition using LCP3, and LCP4. The temperature of the liquid crystal resin composition used was 380 ° C. The results are shown in Tables 1 and 2.

Based on the following method, the physical characteristics of the molded product molded from the liquid crystal resin composition were measured. The evaluation results are shown in Tables 1 and 2.

(Deflection temperature under load)
Under the following molding conditions, the liquid crystal resin composition was injection-molded to obtain a molded product, and the deflection temperature under load was measured in accordance with ISO75-1 and ISO75-1. The deflection temperature under load was used as an index showing the heat resistance of the molded product.
[Molding condition]
Molding machine: Sumitomo Heavy Industries, Ltd., SE100DU
Cylinder temperature:
360 ° C (Examples 1 to 3 and Comparative Examples 1 to 7 and 11)
350 ° C (Comparative Example 8)
370 ° C (Comparative Examples 9 and 10)
Mold temperature: 90 ° C
Injection speed: 33 mm / sec

(Bending test)
The liquid crystal resin composition was injection-molded under the following molding conditions to obtain a molded product having a thickness of 0.8 mm, and the bending strength, bending strain, and bending elastic modulus were measured according to ASTM D790.
[Molding condition]
Molding machine: Sumitomo Heavy Industries, Ltd., SE100DU
Cylinder temperature:
360 ° C (Examples 1 to 3 and Comparative Examples 1 to 7 and 11)
350 ° C (Comparative Example 8)
370 ° C (Comparative Examples 9 and 10)
Mold temperature: 90 ° C
Injection speed: 33 mm / sec

(Minimum filling pressure in relay case)
The liquid crystal resin composition was injection-molded under the following molding conditions (gate: pin gate, gate size: φ0.3 mm) to obtain a relay case as shown in FIGS. 3 (a) and 3 (b).
[Molding condition]
Molding machine: Sumitomo Heavy Industries, Ltd., SE30DUZ
Cylinder temperature:
360 ° C (Examples 1 to 3 and Comparative Examples 1 to 7 and 11)
350 ° C (Comparative Example 8)
370 ° C (Comparative Examples 9 and 10)
Mold temperature: 90 ° C
Injection speed: 200 mm / sec

The minimum injection filling pressure at which a good molded body could be obtained when the above relay case was injection molded was measured as the minimum filling pressure.

(Relay case deformation)
The dimensions of the bottom surface of the relay case shown in FIGS. 3 (a) and 3 (b) obtained as described above were measured by a Mitutoyo Quick Vision 404PROCNC image measuring machine. The measurement was performed before and after the reflow performed under the following conditions, and evaluated according to the following criteria.
◯ (Good): The absolute value of the dimensional change before and after the reflow was less than 0.6% of the dimension before the reflow.
X (defective): The absolute value of the dimensional change before and after the reflow was 0.6% or more of the dimension before the reflow.
[Reflow condition]
Measuring machine: Futaba Kagaku Co., Ltd. Conveyor type hot air circulation dryer DFC-27-022S
Sample feed rate: 0.45 mm / min
Reflow furnace transit time: 5 minutes Preheat zone temperature condition: 185 ° C
Reflow zone temperature conditions: 295 ° C
Peak temperature: 257 ° C

(Swelling during relay case reflow)
From the bottom surface side of the relay case shown in FIGS. 3 (a) and 3 (b) obtained as described above, the pedestal (material is the same as that of the relay case) shown in FIGS. 4 (a) and 4 (b). It was attached and the inside of the relay case was sealed as shown in FIG. 5 (a). After the relay case was subjected to the reflow performed under the above-mentioned conditions, it was allowed to stand on a horizontal desk, and the height of the top surface of the relay case was measured by a Mitutoyo Quick Vision 404PROCNC image measuring machine. At that time, the height is measured at a plurality of positions indicated by black circles in FIG. 5 (b), and the difference between the maximum height and the minimum height from the least squares plane is evaluated as the flatness of the top surface of the relay case according to the following criteria. bottom.
◯ (Good): The flatness was less than 0.45 mm, and the relay case did not swell during reflow.
X (defective): The flatness was 0.45 mm or more, and the relay case swelled during reflow.

(Filler desorption)
After the relay cases shown in FIGS. 3 (a) and 3 (b) obtained as described above were subjected to the reflow performed under the above-mentioned conditions, the desorption state of the filler was observed, and the following criteria were followed. evaluated.
◯ (Good): There was no change, and the desorption of the filler was suppressed.
X (defective): The filler was detached.

(Relay case airtightness)
In the same manner as described above, the inside of the relay case was sealed as shown in FIG. 5 (a). This relay case was subjected to the reflow performed under the above-mentioned conditions, and then immersed in warm water at 70 ° C. for 1 minute. The presence or absence of air bubbles at that time was observed and evaluated according to the following criteria.
○ (Good): No bubbles were observed.
× (defective): Bubbles were observed.

As shown in Tables 1 and 2, in the examples, the melt viscosity, the deflection temperature under load, the bending strength, the bending strain, and the flexural modulus show good values, the minimum filling pressure of the relay case is 80 MPa or less, and the relay case. The evaluations of deformation, swelling during reflow of the relay case, detachment of the relay case filler, and airtightness of the relay case were all good. Therefore, the liquid crystal resin composition according to the present invention has excellent fluidity, and the molded product such as a surface mount relay component obtained from this liquid crystal resin composition has excellent heat resistance and airtightness, and is deformed and filled. It was confirmed that desorption was suppressed. Therefore, the liquid crystal resin composition can be suitably used for manufacturing a surface mount relay component and a surface mount relay.

1 Surface mount relay 2 Base 3 Case 4 Coil block 41 Bobbin 42 Coil 43 Iron core 5 Polaron block 51 Polaron connection 52 Polaron 6 Terminal 7 Printed circuit board 8 Conductor pattern

Claims

A liquid crystal resin composition for a surface mount relay containing (A) a liquid crystal resin, (B) fibrous wollastonite, and (C) mica.
The liquid crystal resin (A) is composed of the following structural units (I) to (VI) as essential constituents.
The content of the constituent unit (I) is 50 to 70 mol% with respect to all the constituent units.
The content of the constituent unit (II) is 0.5 mol% or more and less than 4.5 mol% with respect to all the constituent units.
The content of the constituent unit (III) is 10.25 to 22.25 mol% with respect to all the constituent units.
The content of the constituent unit (IV) is 0.5 mol% or more and less than 4.5 mol% with respect to all the constituent units.
The content of the constituent unit (V) is 5.75 to 23.75 mol% with respect to all the constituent units.
The content of the constituent unit (VI) is 1 to 7 mol% with respect to all the constituent units.
The total content of the constituent unit (II) and the constituent unit (IV) with respect to all the constituent units is 1 mol% or more and less than 5 mol%.
The total content of the constituent units (I) to (VI) is 100 mol% with respect to all the constituent units.
A total aromatic polyesteramide exhibiting optical anisotropy when melted, wherein the molar ratio of the structural unit (VI) to the total of the structural unit (V) and the structural unit (VI) is 0.04 to 0.37. ,
The aspect ratio of the fibrous wollastonite (B) is 8 or more.
For the entire liquid crystal resin composition,
The content of the liquid crystal resin (A) is 55 to 75% by mass.
The content of the fibrous wollastonite (B) is 2.5 to 17.5% by mass.
The content of (C) mica is 15 to 32.5% by mass,
The total content of the (B) fibrous wollastonite and the (C) mica is 25 to 45% by mass.
And
The surface mount relay is a liquid crystal resin composition which is a surface mount relay having a base and terminals protruding from the base, and the terminals are soldered to a printed circuit board.
The total number of moles of the constituent unit (III) and the constituent unit (IV) is 1 to 1.1 times the total number of moles of the constituent unit (V) and the constituent unit (VI), or the constituent unit ( The liquid crystal resin according to claim 1, wherein the total number of moles of 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). Composition.
A surface mount relay component comprising the composition according to claim 1 or 2.
A surface mount relay including the component according to claim 3.