KR20180053412A - Liquid crystalline resin composition for camera module, production method thereof, and camera module using the composition - Google Patents

Abstract

Provided is a liquid crystalline resin composition for a camera module for producing a component for a camera module in which the surface is not easily brushed, the low dusting property is excellent, and the warpage is suppressed.
A liquid crystalline resin composition for a camera module according to the present invention comprises a liquid crystalline resin, (B) a particulate filler and (C) an epoxy group-containing copolymer, wherein the content of the component (A) is 35 To 79 mass%, the content of component (B) is 20 to 60 mass%, the content of component (C) is 1 to 5 mass%, the average primary particle diameter of component (B) is 5 占 퐉 or less, the number of the agglomerates is not more than 5 per cross-section 0.1 mm ^2.

Description

Liquid crystalline resin composition for camera module, production method thereof, and camera module using the composition

The present invention relates to a liquid crystalline resin composition for a camera module, a method for producing the same, and a camera module using the composition.

Liquid crystalline resins represented by liquid crystalline polyester resins are widely used as high-performance high-performance plastics because they have excellent mechanical strength, heat resistance, chemical resistance and electrical properties in a well-balanced manner and excellent dimensional stability. In recent years, liquid crystalline resins have been used in precision machine parts by taking advantage of these features.

In the case of precision instruments, especially optical instruments with lenses, small dust, dust, etc. may affect the performance of the machine. For example, in a component used in an optical device such as a camera module, when small particles of dust, oil or dust adhere to the lens, the optical characteristics of the camera module are remarkably deteriorated. For the purpose of preventing such deterioration of the optical characteristics, components (hereinafter, also referred to as " components for a camera module ") constituting a camera module are usually cleaned by ultrasonic cleaning before assembling, Is removed.

As described above, in the molded article formed by molding the liquid crystalline resin composition, since the molecular orientation of the polymer is particularly large at the surface portion, the surface of the molded article tends to peel off. When such a molded article is ultrasonically cleaned, a brushed phenomenon And such a linted brushed portion causes small dust to be generated.

Therefore, when a liquid crystal resin composition is used as a raw material for a component for a camera module, a special liquid crystal resin composition which does not wrinkle the surface of the molded article even if the molded article is subjected to ultrasonic cleaning is used. As a specific liquid crystalline resin composition, a liquid crystalline resin composition for a camera module including a liquid crystalline resin and specific talc and carbon black is disclosed (see Patent Document 1).

[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2009-242453

However, in the studies of the present inventors, it has been found that the liquid crystalline resin composition for a camera module described in Patent Document 1 has insufficient suppression of brushed surface on the surface of a molded body, A resin composition is required.

Further, according to the examination by the inventors of the present invention, when a molded article such as a lens holder is molded by molding a conventional liquid crystal resin composition for a camera module, the lens module has a large warpage and inconvenience in assembling a camera module.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a camera module for manufacturing a component for a camera module having a surface which is not easily brushed, excellent in low dusting property, And a liquid crystal resin composition for a module.

DISCLOSURE OF THE INVENTION The present inventors have conducted intensive studies in order to solve the above problems. As a result, a liquid crystal resin composition for a camera module, which contains a liquid crystalline resin, a particulate filler having an average primary particle diameter within a specific range, and an epoxy group-containing copolymer at a specified ratio, The above problems can be solved, and the present invention has been accomplished. More specifically, the present invention provides the following.

(1) (A) a liquid crystalline resin,

(B) a particulate filler, and

(C) an epoxy group-containing copolymer,

≪ / RTI >

Wherein the content of the component (A) is 35 to 79 mass%, the content of the component (B) is 20 to 60 mass%, the content of the component (C) is 1 to 5 mass%

(B) has an average primary particle size of 5 탆 or less,

Wherein the number of agglomerates having a particle diameter of 10 탆 or more is 5 or less per 0.1 mm ² of cross-sectional area.

(2) The composition according to (1), wherein the epoxy group-containing copolymer (C) is at least one selected from the group consisting of (C1) an epoxy group-containing olefin copolymer and (C2) an epoxy group-containing styrene copolymer.

(3) obtaining a mixture containing the liquid crystalline resin (A), the particulate filler (B), and the epoxy group-containing copolymer (C)

(1) or (2), wherein the mixing of the liquid crystalline resin (A) with the particulate filler (B) and the mixing of the liquid crystalline resin and the epoxy group- 2). ≪ / RTI >

(4) The above-mentioned mixture is obtained by using an extruder,

(C) the epoxy group-containing copolymer is fed to the side feed port provided in the rear of the main feed port in the extruding direction, or the (C) epoxy group-containing copolymer is fed into the main feed port of the extruder,

The method according to (3), wherein the liquid crystalline resin (A) and the epoxy group-containing copolymer (C) are fed to the main feed port and the granular filler (B) is fed to the side feed port.

(5) A component for a camera module comprising the composition according to (1) or (2).

(6) A camera module comprising the component according to (5).

When a component for a camera module is manufactured using the liquid crystalline resin composition for a camera module of the present invention as a raw material, a component for a camera module whose surface is not easily wrinkled, excellent in low foaming property, and warped is suppressed can be obtained.

1 is a cross-sectional view schematically showing a general camera module.
Fig. 2 is a diagram showing two of the electron micrographs used in Example 1. Fig.
Fig. 3 shows two electron micrographs used in Comparative Example 1. Fig.

Hereinafter, an embodiment of the present invention will be described. However, the present invention is not limited to the following embodiments.

<Liquid crystalline resin composition for camera module>

The liquid crystalline resin composition for a camera module of the present invention contains (A) a liquid crystalline resin, (B) a particulate filler, and (C) an epoxy group-containing copolymer.

[(A) Liquid crystalline resin]

The liquid crystalline resin (A) used in the present invention refers to a melt processible polymer having properties capable of forming an optically anisotropic melt phase. The properties of the anisotropic molten phase can be confirmed by an ordinary polarization test using an orthogonal polarizer. More specifically, identification of the anisotropic molten phase can be made by observing a molten sample placed on a Leitz hot stage at a magnification of 40 times under a nitrogen atmosphere using a Leitz polarization microscope. The liquid crystalline polymer applicable to the present invention exhibits optically anisotropic properties when examined between orthogonal polarizers, for example, in the case of a molten halt state, and usually the polarized light is transmitted.

The kind of the liquid crystalline resin (A) is not particularly limited, and is preferably an aromatic polyester and / or an aromatic polyester amide. Also included are polyesters that partially contain an aromatic polyester and / or an aromatic polyester amide in the same molecular chain. The liquid crystalline resin (A) preferably has a logarithmic viscosity (relative viscosity) of at least about 2.0 dl / g, more preferably 2.0 to 10.0 dl / g when dissolved in pentafluorophenol at a concentration of 0.1 mass% IV) is preferably used.

The aromatic polyester or aromatic polyester amide (A) which can be applied to the present invention is particularly preferably at least one selected from the group consisting of aromatic hydroxycarboxylic acids, aromatic hydroxyamines, and aromatic diamines Is an aromatic polyester or an aromatic polyester amide having, as a constituent component, a constituent unit derived from one kind of compound.

More specifically,

(1) a polyester comprising a constitutional unit derived from at least one of mainly an aromatic hydroxycarboxylic acid and a derivative thereof;

(2) a resin composition comprising a structural unit derived from at least one of (a) an aromatic hydroxycarboxylic acid and a derivative thereof, (b) a structural unit derived from one or more kinds of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, (C) a constituent unit derived from at least one or more kinds of aromatic diols, alicyclic diols, aliphatic diols, and derivatives thereof;

(3) at least one structural unit derived from at least one of (a) an aromatic hydroxycarboxylic acid and a derivative thereof, (b) one or more kinds of aromatic hydroxamines, aromatic diamines and derivatives thereof And (c) a constituent unit derived from one or more of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and derivatives thereof;

(4) a resin composition comprising a structural unit derived from at least one of (a) an aromatic hydroxycarboxylic acid and a derivative thereof, and (b) a structural unit derived from one or more kinds of aromatic hydroxamines, aromatic diamines, (C) a structural unit derived from at least one of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and derivatives thereof; (d) a structural unit derived from an aromatic diol, an alicyclic diol, an aliphatic diol , And a structural unit derived from at least one kind or at least two kinds of derivatives thereof. Further, a molecular weight regulator may be used in combination with the above-mentioned components as required.

Preferable examples of the specific compound constituting the liquid crystalline resin (A) applicable to the present invention include aromatic hydroxycarboxylic acids such as p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, Dihydroxynaphthalene, 4,4'-dihydroxybiphenyl, hydroquinone, resorcin, a compound represented by the following formula (I), and a compound represented by the following formula (II) An aromatic diol such as a compound represented by the formula Aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 4,4'-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and compounds represented by the following formula (III); p-aminophenol, p-phenylenediamine, and other aromatic amines.

(X is a group selected from the group consisting of alkylene (C ₁ -C ₄ ), alkylidene, -O-, -SO-, -SO ₂ -, -S-, and -CO-)

(Y is a group selected from - (CH ₂ ) _n - (n = 1 to 4) and -O (CH ₂ ) _n O- (n = 1 to 4)

The liquid crystalline resin (A) used in the present invention can be prepared by a known method using the above-mentioned monomeric compound (or a mixture of monomers) directly by a polymerization method or an ester exchange method. Usually, A slurry polymerization method or the like is used. The above-mentioned compounds having an ester-forming ability can be used for the polymerization in the form of the ester, and may be modified from the precursor to the ester-forming derivative in the pre-polymerization step. Diaryl tin oxide, titanium dioxide, alkoxytitanium silicates, titanium alcohols, alkali and alkaline earth metal salts of carboxylic acid, BF 3, and the like. _3, and the like. The amount of the catalyst to be used is generally about 0.001 to 1 mass%, particularly about 0.01 to 0.2 mass%, based on the total mass of the monomer. If necessary, the polymer produced by these polymerization methods can be increased in molecular weight by solid state polymerization which is carried out under reduced pressure or in an inert gas.

The melt viscosity of the liquid crystalline resin (A) obtained by the above-mentioned method is not particularly limited. Generally, those having a melt viscosity at a molding temperature of 10 MPa or more and 600 MPa or less at a shear rate of 1000 sec ^-1 can be used. However, a very high viscosity per se is not preferable because the fluidity is extremely deteriorated. The liquid crystalline resin (A) may be a mixture of two or more liquid crystalline resins.

In the liquid crystalline resin composition for a camera module of the present invention, the content of the liquid crystalline resin (A) is 35 to 79 mass%. When the content of the component (A) is 35 mass% or more, it is preferable from the viewpoint of fluidity and bristle suppression on the surface of the molded article, and when the content of the component (A) is 79 mass% or less, the heat resistance is preferable. The preferable content of the component (A) is 40 to 73 mass%, and the more preferable content of the component (A) is 45 to 67 mass%.

[(B) Granular filler]

(B) is a particulate filler, and the average primary particle diameter of the component (B) is 5 占 퐉 or less. If the average primary particle diameter is 5 m or less, the effect of suppressing brushed surface on the surface of the molded article, the low foaming property of the molded article, and the effect of suppressing the warpage deformation of the molded article are likely to be high. The average primary particle diameter is preferably 0.25 to 4.5 mu m, more preferably 0.5 to 4 mu m. In the present specification, the average primary particle diameter is a value measured by a laser diffraction / scattering particle size distribution measurement method.

Examples of the particulate filler of the component (B) include silicates such as silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, clay, diatomaceous earth and wollastonite; Metal oxides such as iron oxide, titanium oxide, zinc oxide and alumina; Metal carbonates such as calcium carbonate and magnesium carbonate; Metal sulfates such as calcium sulfate and barium sulfate; Silicon carbide; Silicon nitride; Boron nitride, and the like. As the component (B), two or more kinds may be used. In the present invention, it is preferable to use silica, alumina, and titanium oxide as the component (B) from the viewpoints of the effect of suppressing the brushed surface of the molded article, the low foaming property of the molded article, It is more preferable to use it.

The content of the component (B) in the liquid crystal composition for a camera module of the present invention is 20 to 60 mass%. If the content of the component (B) is 20 mass% or more, the mechanical strength and the flexural bending temperature necessary for the camera module are easily ensured, and if it is 60 mass% or less, the effect of suppressing brushed surface of the molded article and the low foaming property of the molded article are likely to be high. The preferable content of the component (B) is 25 to 55 mass%, and the more preferable content of the component (B) is 30 to 50 mass%.

[(C) Epoxy group-containing copolymer]

(C) epoxy group-containing copolymers may be used singly or in combination of two or more. The epoxy group-containing copolymer (C) is not particularly limited and includes, for example, at least one member selected from the group consisting of (C1) an epoxy group-containing olefin copolymer and (C2) . (C) to the liquid crystalline resin composition for a camera module contributes to suppressing the brushed surface of the molded body when the molded body obtained by molding the composition is ultrasonically cleaned.

The reason for suppressing the brushed is not clarified, but it is considered that the surface state of the formed article is changed by blending in a certain amount, and the change contributes to suppressing the brushed.

(C1) Examples of epoxy group-containing olefin-based copolymer, for example, α - a copolymer consisting of a structural unit derived from a glycidyl ester of an unsaturated acid-structural units and α, β derived from olefins.

The? -olefin is not particularly limited and includes, for example, ethylene, propylene, and butene, among which ethylene is preferably used. The glycidyl ester of an alpha, beta -unsaturated acid is represented by the following formula (IV). In the general formula (IV), R 'represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Examples of glycidyl esters of ?,? - unsaturated acids include glycidyl acrylate esters, glycidyl methacrylate esters, glycidyl ethacrylate esters and glycidyl esters of itaconic acid, The glycidyl acrylate esters are preferred.

(C1) In the epoxy group-containing olefin-based copolymer, the content of the constituent unit derived from the ? -Olefin is 87 to 98% by mass and the content of the constituent unit derived from the glycidyl ester of the ?,? - unsaturated acid is 13 To 2% by mass.

(C1) The epoxy group-containing olefin-based copolymer may contain, in addition to the above-mentioned two components, an olefinic compound such as acrylonitrile, acrylic acid ester, methacrylic acid ester ,? -Methylstyrene, And 0 to 48 parts by mass of the constitutional unit derived from one or more kinds of the abovementioned unsaturated esters relative to 100 parts by mass of the above two components.

(C1) The epoxy group-containing olefin-based copolymer can be easily prepared by a conventional radical polymerization method using a monomer and a radical polymerization catalyst corresponding to each component. In the presence of a glycidyl ester of an unsaturated acid in the presence of a radical generating agent at 500 to 4000 atm, 100 ~ 300 ℃ suitable solvent or chain transfer agent-more specifically, for example, α-olefin and α, β Or copolymerization in the absence of the catalyst. It is also possible to prepare by melt-graft copolymerizing an α -olefin with a glycidyl ester of an α, β -unsaturated acid and a radical generator in an extruder.

Examples of the (C2) epoxy group-containing styrenic copolymer include a copolymer composed of a constituent unit derived from a styrene and a constituent unit derived from a glycidyl ester of an ?,? - unsaturated acid. The glycidyl ester of the ?,? - unsaturated acid is the same as that described in the component (C1), and thus the description thereof is omitted.

As the styrenes, styrene, α - methylstyrene and the like, brominated styrene, divinylbenzene, it is used as styrene is preferred.

(C2) The epoxy group-containing styrenic copolymer may be a multi-component copolymer containing, as a third component, a constituent unit derived from one or more vinyl monomers other than the above two components. Suitable as the third component are structural units derived from one or more olefinic unsaturated esters such as acrylonitrile, acrylic acid ester, methacrylic acid ester and maleic anhydride. An epoxy group-containing styrenic copolymer containing these constituent units in an amount of 40 mass% or less in the copolymer is preferable as the component (C2).

(C2) In the epoxy group-containing styrenic copolymer, the content of the constituent unit derived from the glycidyl ester of the ?,? - unsaturated acid is 2 to 20 mass%, the content of the constituent unit derived from the styrene is 80 to 80 mass% 98% by mass.

(C2) The epoxy group-containing styrenic copolymer can be prepared by a conventional radical polymerization method using a monomer and a radical polymerization catalyst corresponding to each component. More specifically, usually, styrenes and glycidyl esters of ?,? - unsaturated acids are copolymerized in the presence of a radical generator at 500 to 4000 atm and 100 to 300 ° C in the presence or absence of a suitable solvent or chain transfer agent And the like. It is also possible to prepare by a method in which styrene is mixed with a glycidyl ester of an ?,? - unsaturated acid and a radical generator and melt graft copolymerized in an extruder.

As the epoxy group-containing copolymer (C), the (C1) epoxy group-containing olefin-based copolymer is preferable in terms of heat resistance. When the component (C1) and the component (C2) are used in combination, the ratio between these components can be appropriately selected depending on the required characteristics.

The content of the epoxy group-containing copolymer (C) in the resin composition for a camera module of the present invention is 1 to 5% by mass. When the content of the component (C) is 1% by mass or more, it is necessary from the viewpoint of suppressing brushed surface of the molded article, and the content of 5% by mass or less is necessary for obtaining a good molded article without inhibiting flowability. More preferably, the content is 2 to 4% by mass.

[(D) Carbon Black]

The carbon black (D) used as an optional component in the present invention is not particularly limited as long as it is generally available for use in resin coloring. Usually, (D) carbon black contains a lump form in which primary particles are formed by agglomeration. However, as long as the lump form material having a size of 50 탆 or more is not significantly contained, the molded article Many milky protrusions on the surface (fine protrusions like fine irregularities with aggregated carbon black) are not easily generated. If the content of the particles having a particle diameter of 50 占 퐉 or more of the mass of the mass is 20 ppm or less, the effect of suppressing the brusiness on the surface of the molded article and the low foaming property of the molded article are liable to increase. The preferable content is 5 ppm or less.

The blending amount of (D) carbon black is preferably in the range of 0.5 to 5% by mass in the liquid crystalline resin composition for a camera module. When the blending amount of carbon black is 0.5 mass% or more, the blackness of the obtained resin composition is not easily deteriorated and the light shielding property is not unstable. When the amount of the carbon black is less than 5% by mass, it is not economical, and the protrusions are not easily generated.

[Other ingredients]

To the liquid crystalline resin composition for a camera module of the present invention may be added other polymers, other fillers, generally known substances added to synthetic resins, such as stabilizers such as antioxidants and ultraviolet absorbers, Antistatic agents, flame retardants, colorants such as dyes and pigments, lubricants, releasing agents, crystallization accelerators, crystal nucleating agents and the like can be appropriately added according to the required performance.

Other fillers are fillers other than the particulate filler (B), and examples thereof include plate fillers such as talc. However, it is preferable that the liquid crystalline resin composition for a camera module of the present invention does not contain a plate-shaped filler.

[Other characteristics of liquid crystal resin composition for camera module]

In the liquid crystalline resin composition for a camera module of the present invention, the number of agglomerates having a particle diameter of 10 탆 or more is preferably 5 or less, more preferably 3 or less, and more preferably 2 or less, per 0.1 mm ^{2 of} cross section. According to the studies of the present inventors, in the liquid crystalline resin composition, the component (B) and the component (C) tend to form agglomerates. If the degree of agglomeration of these components is large, It is difficult to be expressed. However, if the number of agglomerates is 5 or less per 0.1 mm ² of the cross-sectional area, the effect of suppressing the brushed surface of the molded article and the low foaming property of the molded article are liable to increase.

The number of agglomerates having a particle diameter of 10 mu m or more in the liquid crystalline resin composition is specifically measured as follows. A molded article obtained by injection molding a liquid crystalline resin composition under the conditions shown in the following Examples was trimmed to have a cross section perpendicular to the flow direction at the time of molding by using a microtome, Is observed with a scanning electron microscope to measure the number of aggregates having a particle diameter of 10 탆 or more and dividing this number by the area of the cross section to be observed to obtain the number of aggregates per 0.1 mm ^{2 of} cross section. As the particle size of the aggregate, the longest diameter in the cross section is adopted.

The shape of the component (B) in the liquid crystalline resin composition for a camera module of the present invention is different from the shape of the component (B) before it is blended. The shape of the above-mentioned component (B) is a shape before being blended. If the shape before compounding is as described above, a component for a camera module in which the surface is not easily brushed can be obtained.

The liquid crystalline resin composition for a camera module of the present invention obtained as described above preferably has a melt viscosity of 90 Pa · sec or less and more preferably 80 Pa · sec or less in view of fluidity at the time of melting and moldability. As the melt viscosity in this specification, a value obtained by a measurement method in accordance with ISO 11443 is adopted at a cylinder temperature and a shear rate of 1000 sec ^-1 higher than the melting point of the liquid crystalline resin by 10 to 20 ° C.

[Preparation of liquid crystalline resin composition for camera module]

The liquid crystalline resin composition for a camera module according to the present invention is a liquid crystalline resin composition comprising (A) a liquid crystalline resin, (B) a granular resin, and (B) a liquid crystalline resin, in that the formation of aggregates of the particulate filler (B) and the epoxy group- (A) a liquid crystalline resin and (B) a particulate filler, and (A) a liquid crystalline resin and (C) an epoxy group-containing copolymer. Is not carried out at the same time. That is, it is preferable to separately add the particulate filler (B) and the epoxy group-containing copolymer (C) to the liquid crystalline resin (A). Specifically, for example, (A) a liquid crystalline resin and (C) an epoxy group-containing copolymer are mixed with a mixture containing (A) a liquid crystalline resin and (B) a particulate filler, and / (B) a granular filler is mixed with a mixture containing an epoxy group-containing copolymer. The other component (A) is mixed with the liquid crystalline resin together with the particulate filler (B) and / or the epoxy group-containing copolymer (C). The mixing of the components is performed, for example, by melt-kneading using a single-screw or twin-screw extruder.

Particularly, when an extruder is used to obtain the mixture, a liquid crystalline resin (A) and a particulate filler (B) are fed to the main feed port of the extruder and fed into the side feed opening (C) an epoxy group-containing copolymer, or supply the liquid crystal resin (A) and the epoxy group-containing copolymer to the main feed port and supply the particulate filler (B) to the side feed port. This effectively prevents the formation of agglomerates of the particulate filler (B) and the epoxy group-containing copolymer (C), and as a result, the effect of suppressing brushed surface of the molded article and the low foaming property of the molded article are liable to increase.

<Parts for camera module and camera module>

A component for a camera module is manufactured using the liquid crystalline resin composition for a camera module. When the resin composition of the present invention is used as a raw material, the surface of a component for a camera module does not easily wrinkle. Since the components for the camera module are ultrasonically cleaned, the surface should not be easily brushed even when ultrasonic cleaning is performed. When the resin composition of the present invention is used, even if ultrasonic cleaning of a component for a camera module is carried out under stronger conditions, a dropout that causes dust or the like is not generated or hardly occurs. Therefore, after the parts for the camera module are bonded to the finished product, the surface of the parts for the camera module is dust generated by brushed, hardly affecting the quality of the finished product.

A component for a camera module formed by molding a liquid crystal resin composition for a camera module of the present invention will be described. A cross section of a typical camera module is schematically shown in Fig. 1, the camera module 1 includes a substrate 10, an optical element 11, a lead wiring 12, a lens holder 13, a barrel 14, a lens 15 ), An IR filter 16, and a guide 17.

The optical element 11 is disposed on the substrate 10 and the optical element 11 and the substrate 10 are electrically connected to the lead wiring 12.

The guide 17 is disposed on the substrate 10 and the lens holder 13 is disposed on the guide 17. The guide 17 and the lens holder 13 wrap the optical element 11 . The lens holder 13 has an opening at the top, and a helical groove is formed in the opening wall.

The barrel 14 has a cylindrical shape, and the lens 15 is held in a substantially cylindrical shape. The helical convex portion and the helical groove portion formed on the opening wall surface of the lens holder 13 are engaged with each other by the helical convex portion formed on the side wall of one end of the cylinder, 13). Further, the IR filter 16 is disposed at one end of the barrel 14 so as to close one end of the cylindrical barrel 14. As shown in Fig. 1, the IR filter 16 and the lens 15 are arranged substantially in parallel.

In the camera module 1 shown in Fig. 1, the lens holder 13 is arranged so that the magnetic force generated by the coil (not shown) wound around the lens holder 13 and the permanent magnet (not shown) The distance between the lens 15 and the optical element 11 changes as the optical element 11 moves up and down the guide 17. [ By adjusting this distance, the focus of the camera can be adjusted.

In the camera module 1 as described above, the lens holder 13 and / or the barrel 14, which are components for the camera module, can be manufactured using the liquid crystalline resin composition for a camera module of the present invention as a raw material. A typical liquid crystalline resin composition is not suitable as a raw material for producing such a component. The following problems arise when the lens holder 13 and / or the barrel 14 are manufactured using a general liquid crystalline resin composition as a raw material.

In a molded article obtained by molding a general liquid crystalline resin composition, since the molecular orientation of the polymer is particularly large at the surface portion, the surface of the molded article tends to be wrinkled, and such a brushed shape causes a small amount of dust. When such small particles adhere to the lens 15 or the like, the performance of the camera module deteriorates.

The components for the camera module such as the lens holder 13 and the barrel 14 are ultrasonically cleaned before being coupled to the camera module 1 for the purpose of removing dust on the surface or small dust. However, since the surface of a molded article obtained by molding a general liquid crystalline resin composition is easy to wrinkle, the surface of the molded article is napped by ultrasonic cleaning. In view of such a problem, the molded article formed by molding the liquid crystalline resin composition can not be ultrasonically cleaned.

The above focus adjustment is carried out in such a manner that the lens holder 13 is rotated by the action of a magnetic force generated by a coil (not shown) wound around the lens holder 13 and a permanent magnet (not shown) 17). At this time, since the surface of the molded article obtained by molding a general liquid crystalline resin composition is easily wrinkled as described above, there is a possibility that the surface is peeled off and a peeled product is generated. Such peeling material becomes small dust, and is likely to be adhered to the lens 15 or the like and deteriorate the performance of the camera module.

As described above, if a liquid crystalline resin composition is used as a raw material for the lens holder 13 and / or the barrel 14, defects tend to occur. However, the liquid crystalline resin composition for a camera module of the present invention is made into a molded article The surface condition of the molded article can be improved to such an extent that even if ultrasonic cleaning is performed on the molded article, the problem of brushed surface hardly occurs. Therefore, it can be suitably used as a raw material for the lens holder 13 and / or the barrel 14.

When the liquid crystal resin composition for a camera module of the present invention is used for the lens holder 13, the material of the guide 17 may be those other than the liquid crystal resin composition for a camera module of the present invention. Specifically, And the like.

[ Example ]

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

<Liquid Crystalline Resin>

Liquid crystalline polyester amide resin

After the following raw materials were charged into the polymerization vessel, the temperature of the reaction system was raised to 140 캜 and the reaction was carried out at 140 캜 for 1 hour. Thereafter, the temperature was further raised to 340 ° C for 4.5 hours, and thereafter, the pressure was reduced to 10 Torr (i.e., 1330 Pa) over 15 minutes, and molten polymerization was carried out while distilling the acetic acid, the excess acetic anhydride and other low boiling components Respectively. After the stirring torque reached a predetermined value, nitrogen was introduced to bring the pressure from the reduced pressure state to the pressurized state through the atmospheric pressure. The polymer was discharged from the lower part of the polymerization vessel and the strands were pelletized to obtain pellets. The obtained pellets were subjected to heat treatment at 300 DEG C for 2 hours under a nitrogen gas stream to obtain a desired polymer. The obtained polymer had a melting point of 334 占 폚 and a melt viscosity of 14.0 Pa 占 퐏. The melt viscosity of the polymer was measured in the same manner as the melt viscosity measurement method described later.

 (I) 4-hydroxybenzoic acid; 188.4 g (60 mol%)

 (II) 2-hydroxy-6-naphthoic acid; 21.4 g (5 mol%)

 (III) terephthalic acid; 66.8 g (17.7 mol%)

 (IV) 4,4'-dihydroxybiphenyl; 52.2 g (12.3 mol%)

 (V) 4-acetoxyaminophenol; 17.2 g (5 mol%)

 Metal catalysts (potassium acetate catalysts); 15 mg

 Acylating agents (anhydrous acetic acid); 226.2 g

&Lt; Materials other than the liquid crystalline resin &

Granular filler 1: Admaphine SO-C2 (manufactured by Admatechs, silica, average primary particle diameter 0.5 占 퐉)

Granular filler 2: Admafine AO-502 (alumina, average primary particle size 0.7 mu m, manufactured by Admatechs Co., Ltd.)

Granular filler 3: Denka Fused silica FB-5SDC (available from Denki Kagaku Kogyo K.K., silica, average primary particle diameter 4.0 탆)

- Granular filler 4: EGB 731 (glass beads, made by Potters &amp; Balotini Co., Ltd., average primary particle diameter: 20.0 탆)

Plate-like filler: GH3 (manufactured by Hayashi Kasei Corporation, talc, average primary particle diameter 3.0 m)

Carbon black: VULCAN XC305 (manufactured by Cabot Japan Co., Ltd., average particle diameter: 20 nm, particle diameter of not less than 50 μm, not more than 20 ppm)

Bond Fast 2C (ethylene-glycidyl methacrylate copolymer, glycidyl methacrylate content: 6% by mass, manufactured by Sumitomo Chemical Co., Ltd.) (epoxy group-containing olefin-based copolymer)

&Lt; Production of liquid crystal resin composition for camera module >

The above components were melt-kneaded at a cylinder temperature of 350 占 폚 using a twin-screw extruder (TEX30 ? Type, manufactured by Nippon Shokubai Co., Ltd.) in the ratio shown in Table 1 or Table 2 (unit: mass% To obtain pellets of the resin composition composition. In Comparative Example 1, the liquid crystalline resin and the carbon black were supplied to the main feed port of the extruder, and the particulate filler and the epoxy group-containing copolymer were fed into the side feed port provided in the rear of the main feed port in the extrusion direction. On the other hand, in Examples and Comparative Examples, the liquid crystalline resin, the epoxy group-containing copolymer and the carbon black were fed into the main feed port of the extruder, and the particulate filler was supplied to the side feed port.

<Melt viscosity>

The melt viscosity of the liquid crystalline resin composition for a camera module in Examples and Comparative Examples was measured using the above pellets. Specifically, the apparent melt viscosity at a cylinder temperature of 350 DEG C and a shear rate of 1000 sec &lt; ^-1 &gt; was measured according to ISO 11443 using a capillary rheometer (capillograph 1D made by TOYO SEIKI Co., Ltd., piston diameter 10 mm) Respectively. For the measurement, an orifice having an inner diameter of 1 mm and a length of 20 mm was used. The results are shown in Tables 1 and 2.

&Lt; Dust generation number &

The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine (&quot; SE30DUZ &quot;, manufactured by Sumitomo Heavy Industries, Ltd.) to obtain a molded article of 12.5 mm x 120 mm x 0.8 mm. This molded article was used as a test piece.

〔Molding conditions〕

Cylinder temperature: 350 ° C

Mold temperature: 90 ℃

Injection speed: 80mm / sec

〔evaluation〕

The test piece was attached to an ultrasonic cleaner (output: 300 W, frequency: 45 kHz) in water (room temperature, 10 ml) for 3 minutes at room temperature. Thereafter, the number of particles of 2 mu m or more existing in the water was measured with a particle counter (liquid fine particle counter KL-11A (PARTICLECOUNTER) manufactured by RION Corporation) and evaluated as the dust generation number. The results are shown in Tables 1 and 2.

&Lt; Floor Plan (Flatness) >

The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine ("SE-100 DU" manufactured by Sumitomo Heavy Industries, Ltd.) to prepare five flat test specimens of 80 mm × 80 mm × 1 mm. The first plate-like test piece was placed on a horizontal plane, and the height from the horizontal plane was measured at nine positions on the flat plate-like test piece using a CNC image measuring machine (model: QVBHU404-PRO1F) manufactured by Mitsutoyo Co., , And the average height was calculated from the obtained measurement values. The position at which the height was measured was a square having a side of 74 mm on the principal plane of the flat test specimen so that the distance from each side of the main plane was 3 mm and the center of each square of this square, , And the position corresponding to the intersection of two diagonal lines of the square. A height from the horizontal plane is equal to the average height, and a plane parallel to the horizontal plane is a reference plane. Among the heights measured at the nine places, the maximum height and the minimum height from the reference plane were selected and the difference between them was calculated. In the same manner, the above-mentioned difference was calculated for the other four flat plate test pieces, and the obtained five values were averaged to obtain the value of the flatness. The results are shown in Tables 1 and 2.

〔Molding conditions〕

Cylinder temperature: 350 ° C

Mold temperature: 80 ℃

Injection speed: 33mm / sec

Holding pressure: 60 MPa

&Lt; Number of aggregates &

The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine (&quot; SE30DUZ &quot;, manufactured by Sumitomo Heavy Industries, Ltd.) to obtain a molded article of 12.5 mm x 120 mm x 0.8 mm. S-4700 &quot; manufactured by Hitachi High Technologies, Ltd.) was applied to a section selected randomly from the obtained sample by trimming the formed body with a cross section perpendicular to the flow direction at the time of molding by using a microtome, magnification for observation in 1000 times), and measuring the number of particle diameter or more 10㎛ aggregates, and the number of the, by dividing by the area of the observation target section was determined the number of cross-sectional area per 0.1mm ² wherein the agglomerates. Ten electron micrographs were used when observing with a scanning electron microscope. The results are shown in Tables 1 and 2. Fig. 2 shows two of the electron microscopic photographs used in Example 1, and Fig. 3 shows two of the electron microscopic photographs used in Comparative Example 1. Fig.

〔Molding conditions〕

Cylinder temperature: 350 ° C

Mold temperature: 90 ℃

Injection speed: 80mm / sec

(*) Since the glass beads themselves have an average primary particle diameter of 20.0 μm, the number of agglomerates is not evaluated.

As is clear from the results shown in Tables 1 and 2, it was confirmed that the molded article produced by using the pellets of the examples had a small amount of dust generated even when subjected to ultrasonic cleaning. Further, the molded article had a small numerical value in the plan view. From these results, it can be said that the molded article obtained by molding the pellets of the examples is significantly different in surface state from the molded article obtained by molding the ordinary liquid crystalline resin composition pellets such as the comparative example, and the warpage is suppressed.

As is apparent from the comparison between Example 1 and Comparative Example 1, when the granular filler and the epoxy group-containing copolymer were supplied simultaneously to the extruder, the number of agglomerates having a particle diameter of 10 m or more increased and the generation of dust also increased, Containing copolymer was separately fed into an extruder, it was confirmed that the number of aggregates having a particle diameter of 10 μm or more was greatly reduced, and the generation of dust was also reduced.

1 camera module
10 substrate
11 optical element
12 lead wiring
13 Lens Holder
14 barrels
15 lens
16 IR filter
17 Guide

Claims (6)

(A) a liquid crystalline resin,
(B) a particulate filler, and
(C) an epoxy group-containing copolymer,
&Lt; / RTI &gt;
Wherein the content of the component (A) is 35 to 79 mass%, the content of the component (B) is 20 to 60 mass%, the content of the component (C) is 1 to 5 mass%
(B) has an average primary particle size of 5 탆 or less,
Wherein the number of agglomerates having a particle diameter of 10 탆 or more is 5 or less per 0.1 mm ² of cross-sectional area. The method according to claim 1,
(C) the epoxy group-containing copolymer is at least one member selected from the group consisting of (C1) an epoxy group-containing olefin copolymer and (C2) epoxy group-containing styrene copolymer. Comprising obtaining a mixture containing the liquid crystalline resin (A), the particulate filler (B), and the epoxy group-containing copolymer (C)
(1) or (2), wherein the mixing of the liquid crystalline resin (A) with the particulate filler (B) and the mixing of the liquid crystalline resin (A) and the epoxy group- &Lt; / RTI &gt; The method of claim 3,
To obtain the mixture, an extruder was used,
(C) the epoxy group-containing copolymer is fed to the side feed port provided in the rear of the main feed port in the extruding direction, or the (C) epoxy group-containing copolymer is fed into the main feed port of the extruder,
Supplying the liquid crystalline resin (A) and the epoxy group-containing copolymer (C) to the main feed port and feeding the particulate filler (B) to the side feed port. A component for a camera module comprising the composition according to claim 1 or 2. A camera module comprising the component according to claim 5.

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