Liquid crystal polyester resin composition, molded article, and electronic component material containing the same

Abstract

To provide: a liquid crystal polyester composition that can reduce physical damage caused by internal and external friction and internal and external impact, have improved mechanical properties such as tensile strength and impact strength, and improved weld line impact strength, provide dimensional stability due to low shrinkage, and minimize fibril and dust generation; and an electronic component material including the same.SOLUTION: A liquid crystal polyester resin composition comprises a liquid crystal polyester resin, a polyphenylene sulfide resin, carbon-based fillers, and inorganic fillers, where the inorganic fillers comprise glass powder.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to liquid crystal polyester resin compositions, molded articles, and electronic component materials containing the same, and more specifically, to liquid crystal polyester resin compositions, molded articles, and electronic component materials containing the same that exhibit excellent mechanical properties, weld line impact strength, dimensional stability, and low dust characteristics. [Background technology]

[0002] Liquid crystal polyester resin refers to a molten polyester resin in which the molecular chains within the polymer are arranged regularly and parallel to each other in a molten state. This state of each molecule in which it is arranged is usually called the liquid crystal state or the nematic phase of a liquid crystal material. The molecules in such a polymer are generally thin, long, and flat, and exhibit very high mechanical strength, electrical properties, and heat resistance along the long chains of the molecules.

[0003] Resin compositions containing liquid crystal polyester resin have high heat resistance and high fluidity properties and are widely used as materials for various electrical / electronic products. Furthermore, as small portable electronic products such as notebook computers are becoming thinner and lighter while maintaining excellent performance, the demand for liquid crystal polyester resin compositions with excellent moldability is increasing.

[0004] However, liquid crystal polyester resin compositions have the characteristic that the molten polymer does not lose its crystalline structure even while flowing. When injected into molded products with complex structures, weld lines are formed at the boundaries where the resins meet during the molding process. Since the strength of such weld lines is very weak, the molded product can be damaged by external or internal impacts and friction.

[0005] Furthermore, molded articles of liquid crystal polyester resin composition may undergo fibrillation, a phenomenon in which the surface peels off and fuzz forms due to ultrasonic cleaning or friction with other components. When molded articles of liquid crystal polyester resin composition are used as electronic components in electronic devices, foreign matter such as dust and fibrils that detach from the fibrillated areas can significantly degrade the performance of the electronic device.

[0006] For example, in the case of electronic components, especially optical equipment with lenses, dust and other particles adhering to the lens can significantly degrade its optical properties. Fibrillation can occur when assembling or operating camera modules, and this is also true when assembling or operating camera modules in mobile phones. Specifically, when the camera autofocus function is activated, dust can be generated from the surface of the camera module components due to their sliding movement, and dust is also easily generated when the device is subjected to impact or dropped. In recent years, miniaturization of peripheral electronic devices and accessories used inside electronic equipment has become essential, and as a result, the need has emerged to manufacture dust-sensitive semiconductor and optical material components using electronic component materials that generate less dust.

[0007] In connection with this, Korean Patent Publication No. 10-2014-0007792 discloses a liquid crystal polyester resin composition that can yield molded articles that are less susceptible to fibrillation. [Overview of the project] [Problems that the invention aims to solve]

[0008] The object of the present invention is to provide a liquid crystal polyester composition and an electronic component material containing the same, which reduces physical damage caused by internal and external friction and internal and external impact, improves mechanical properties such as tensile strength and impact strength, and impact strength at weld lines, has dimensional stability due to a low shrinkage rate, and minimizes the generation of fibrils and dust. [Means for solving the problem]

[0009] In one aspect of the present invention, the present invention can provide a liquid crystal polyester resin composition comprising a liquid crystal polyester resin; a polyphenylene sulfide resin; a carbon-based filler; and an inorganic filler, wherein the inorganic filler comprises glass powder.

[0010] Preferably, a liquid crystal polyester resin composition can be provided, comprising: liquid crystal polyester resin in an amount of 55% to 85% by weight; polyphenylene sulfide resin in an amount of 1% to less than 15% by weight; carbon-based filler in an amount of 1% to 5% by weight; and inorganic filler in an amount of 5% to 30% by weight.

[0011] Preferably, the carbon-based filler is one or more selected from the group consisting of carbon black, graphite, and carbon nanotubes, and a liquid crystal polyester resin composition can be provided.

[0012] Preferably, the inorganic filler further comprises one or more selected from the group consisting of serpentine, montmorillonite, talc, micas (biotite, muscovite, phlogopite), chlorite, glass flakes, silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, clay, diatomaceous earth, wollastonite, iron oxide, titanium oxide, zinc oxide, alumina, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, silicon carbide, silicon nitride, boron nitride, potassium titanate, and molybdenum disulfide (MoS2), thereby providing a liquid crystal polyester resin composition.

[0013] Preferably, a liquid crystal polyester resin composition can be provided in which the weld line impact strength of a molded article produced from the liquid crystal polyester resin composition exceeds 20 J / m.

[0014] Preferably, a liquid crystal polyester resin composition can be provided in which the molded article produced from the liquid crystal polyester resin composition has a dent depth of less than 30 μm.

[0015] Preferably, the dent volume of the molded article produced from the liquid crystal polyester resin composition is 14,600,000 μm³. 3 The following liquid crystal polyester resin compositions can be provided.

[0016] In another aspect of the present invention, the present invention can provide a liquid crystal polyester resin composition comprising a liquid crystal polyester resin; a polyphenylene sulfide resin; and a filler, wherein when a tape is adhered to and then peeled off a test piece made from the liquid crystal polyester resin composition, the peeled area is less than 15% of the area of ​​the test piece adhered to the tape.

[0017] In yet another aspect of the present invention, the present invention can provide a molded article manufactured from the liquid crystal polyester resin composition.

[0018] In yet another aspect of the present invention, the present invention can provide an electronic component material comprising the liquid crystal polyester resin composition. [Effects of the Invention]

[0019] The liquid crystal polyester resin composition, molded article, and electronic component material containing the same according to the present invention have excellent mechanical properties in terms of tensile strength and impact strength, and also have improved weld line impact strength.

[0020] Furthermore, the liquid crystal polyester resin composition according to the present invention exhibits excellent dimensional stability because it has a low shrinkage rate in the MD direction (resin flow direction) and the TD direction (direction perpendicular to the resin flow).

[0021] Furthermore, the liquid crystal polyester resin composition, molded article, and electronic component material containing the same according to the present invention suppress the generation of dust and fibrils against internal and external friction and impact.

[0022] In addition, since the area peeled off by internal and external factors including stickiness, friction, or vibration is small, damage to molded products and electronic components to be manufactured hereafter, and generation of dust and fibrils are significantly reduced.

[0023] In addition, the liquid crystal polyester resin composition, molded product, and electronic component material including the same according to the present invention minimize the number of generated dust and fibrils, are excellent in weld line impact strength, and can be used as component materials for electronic products sensitive to internal and external impacts and internal and external friction. In particular, the present invention is applied to components for camera modules or components for camera modules of mobile phones, and can maintain or improve optical performance such as the number of pixels and image quality.

Mode for Carrying Out the Invention

[0024] Hereinafter, the present invention will be described.

[0025] All terms (including technical and scientific terms) used in this specification can be used in a meaning commonly understood by those having ordinary knowledge in the technical field to which the present invention pertains, unless otherwise defined. Also, each commonly used pre-defined term is not ideally or excessively interpreted unless clearly and specifically defined. <able>

[0026] Also, throughout this specification, when one part "includes" one component, this means that, unless otherwise stated to the contrary, it can further include other components rather than excluding other components.

[0027] As an embodiment of the present invention, the liquid crystal polyester resin composition can include a liquid crystal polyester resin, a polyphenylene sulfide resin, and a filler.

[0028] The liquid crystal polyester resin used in the present invention exhibits liquid crystallinity in a molten state, and is particularly preferably melted at a temperature of 450°C or lower.

[0029] When considering its mechanical strength and injection moldability, liquid crystal polyester resin can have a weight-average molecular weight of approximately 10,000 to 300,000, preferably approximately 10,000 to 50,000. If the weight-average molecular weight of the liquid crystal polyester resin is less than 10,000, the mechanical strength will be poor and molded products may break, while if the weight-average molecular weight exceeds 300,000, the fluidity of the resin will decrease, making injection molding difficult.

[0030] The liquid crystal polyester resin may be included in an amount of about 55% by weight or more and about 85% by weight or less based on the total weight of the liquid crystal polyester resin composition, preferably about 60% by weight or more and about 80% by weight or less, and more preferably about 65% by weight or more and about 80% by weight or less. If the liquid crystal polyester resin component is included in an amount of less than about 55% by weight, the fluidity of the resin composition will decrease, which may make fine injection molding difficult. If the liquid crystal polyester resin component is included in an amount exceeding about 85% by weight, the fluidity of the resin composition will become excessively high, which may worsen the strength and heat resistance of molded articles and electronic components manufactured therefrom.

[0031] As the liquid crystal polyester resin, one or more may be selected from the group consisting of liquid crystal polyesteramide, liquid crystal polyester ether, liquid crystal polyester carbonate, and liquid crystal polyester imide.

[0032] Preferably, the liquid crystal polyester resin is a fully aromatic liquid crystal polyester composed using only aromatic compounds as monomer materials. Typical examples of the fully aromatic liquid crystal polyester resin include resins produced by polymerizing (polycondensing) one or more compounds selected from the group consisting of aromatic hydroxycarboxylic acids, aromatic dicarboxylic acids, aromatic diols, aromatic hydroxyamines, and aromatic diamines; resins produced by polymerizing two or more aromatic hydroxycarboxylic acids; resins produced by polymerizing one or more compounds selected from the group consisting of aromatic dicarboxylic acids, aromatic diols, aromatic hydroxyamines, and aromatic diamines; and resins produced by polymerizing a polyester such as polyethylene terephthalate with an aromatic hydroxycarboxylic acid.

[0033] Liquid crystal polyester resin can be produced by polycondensing one or more aromatic monomers to form a liquid crystal polyester prepolymer, and then by solid-phase polycondensation of the formed prepolymer. By-products generated during the solid-phase polycondensation reaction can be removed by purging with an inert gas or by vacuum.

[0034] The liquid crystal polyester resin that may be included in the resin composition of the present invention can be produced, for example, by polymerizing one or more monomers selected from the group including hydroxybenzoic acid (HBA), hydroxynaphthoic acid (HNA), biphenol (BP), terephthalic acid (TPA), and hydroxyacetanilide (APAP).

[0035] For example, liquid crystal polyester resins can be polymerized containing 56 mol% to 66 mol% hydroxybenzoic acid (HBA), 2 mol% to 8 mol% hydroxynaphthoic acid (HNA), 9 mol% to 17 mol% biphenol (BP), 11 mol% to 21 mol% terephthalic acid (TPA), and 2 mol% to 8 mol% hydroxyacetanilide (APAP). Liquid crystal polyester resins polymerized with such mol% combinations can ensure fluidity, and resin compositions containing them can improve the mechanical properties of the product, such as impact strength, while minimizing the generation of dust and fibrils.

[0036] Polyphenylene sulfide resin (hereinafter referred to as PPS resin) is included in the resin composition of the present invention and can act as an impact reinforcement agent.

[0037] As the polyphenylene sulfide resin, one or more linear resins and crosslinked resins can be used. Specifically, considering thermal stability and workability, a polyphenylene sulfide resin having a melt index (MI) of 10 g / 10 min to 300 g / 10 min under the conditions of 316°C and a load of 2.16 kg can be used.

[0038] Polyphenylene sulfide resin may be included in an amount of 1% or more by weight and less than 15% by weight, based on the total weight of the liquid crystal polyester resin composition. If polyphenylene sulfide resin is not included or is included in an amount of less than 1% by weight, fibrillation may occur on the surface of the molded articles or electronic components manufactured, potentially leading to product defects. Furthermore, if polyphenylene sulfide resin is included in an amount of 15% by weight or more, the mechanical properties and dent (DENT) properties of the liquid crystal polyester resin composition may deteriorate.

[0039] The filler can include all carbon-based and inorganic fillers.

[0040] As the carbon-based filler, one or more selected from the group consisting of carbon black, graphite, and carbon nanotubes can be used alone or in combination, and preferably carbon black can be used. The carbon-based filler may be included in an amount of about 1% by weight or more to about 5% by weight or less based on the total weight of the liquid crystal polyester resin composition. For example, carbon black can be used to ensure light shielding properties and may be included in an amount of about 1% by weight or more to about 5% by weight or less based on the total weight of the liquid crystal polyester resin composition. If the amount of carbon black is less than about 1% by weight, the jet blackness of the liquid crystal polyester resin composition may decrease, making it difficult to ensure sufficient light shielding properties. If the amount of carbon black exceeds about 5% by weight, it may solidify without being uniformly dispersed in the liquid crystal polyester resin composition, which may cause a decrease in physical properties and may increase the likelihood of aggregates separating as dust.

[0041] Inorganic fillers can be used to improve mechanical strength, heat resistance, and impact dent resistance. The formulation of inorganic fillers with liquid crystal polyester resin must be carried out in a manner that does not damage the mechanical properties such as strength, rigidity, and hardness, as well as the heat resistance and electrical properties of the polyester resin. Any non-fibrous inorganic filler can be used, including plate-type fillers and granular fillers.

[0042] Examples of plate-like fillers include serpentine, montmorillonite, talc, mica (biotite, muscovite, phlogopite), chlorite, and glass flakes.

[0043] Examples of granular fillers include silica, quartz powder, glass beads, glass powder, silicates such as 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; molybdenum disulfide; silicon carbide; silicon nitride; boron nitride; and potassium titanate.

[0044] As inorganic fillers, one or more plate-type fillers or one or more granular fillers may be used, or one or more plate-type fillers and one or more granular fillers may be used. For example, mica as a plate-type filler and glass powder as a granular filler can be used in combination.

[0045] For example, mica is a plate-shaped filler that can improve mechanical properties and heat resistance, and provide dimensional stability to molded products.

[0046] Conventionally, glass powder had amorphous properties, making it difficult to use in liquid crystal polyester resin compositions. The liquid crystal polyester resin composition of the present invention may preferably contain glass powder, and by including glass powder, the weld line impact strength can be improved, good quality can be obtained in tape tests, the generation of dust and fibrils can be suppressed, and dimensional stability can be improved because the shrinkage rate measured in the MD and TD directions is low.

[0047] The D50 of the glass powder may be 2 μm to 40 μm in size.

[0048] The inorganic filler may be included in an amount of 5% by weight or more and 35% by weight or less, preferably 5% by weight or more and less than 30% by weight, and more preferably 5% by weight or more and 25% by weight or less, based on the total weight of the liquid crystal polyester resin composition.

[0049] The inorganic filler preferably includes glass powder, and two or more types can be used. In this case, the glass powder may be present in an amount of about 1% by weight or more and less than about 18% by weight, preferably about 1% by weight or more and about 15% by weight or less. The inorganic filler other than glass powder may be present in an amount of 4% by weight or more and about 17% by weight or less, preferably 4% by weight or more and about 15% by weight or less.

[0050] The present invention allows for the production of molded articles or electronic component materials from a liquid crystal polyester resin composition containing the above-mentioned components. The molded articles or electronic component materials of the present invention exhibit improved tensile strength, impact strength, and weld line impact strength, and achieve good quality in tape tests, where the peel area is less than 15% of the area of ​​the test piece adhered to the tape when the tape is applied and then peeled off. Furthermore, the generation of dust and fibril is suppressed, and the shrinkage rate measured in the MD and TD directions is low, resulting in excellent dimensional stability. Specifically, the liquid crystal polyester resin composition of the present invention can be applied to camera module components of mobile phones or smartphones, contributing to the maintenance and improvement of optical performance such as pixel count and image quality.

[0051] The present invention will be specifically described below through the following embodiments, but the present invention is not limited by these embodiments.

[0052] Manufacturing example: Manufacturing of liquid crystal polyester resin

[0053] 13,000 g (127.3 mol) of acetic anhydride was added to a 1,200 L batch reactor. While stirring, monomers of 20,000 g (144.8 mol) of parahydroxybenzoic acid (HBA), 2,200 g (11.8 mol) of hydroxynaphthoic acid (HNA), 5,400 g (29.3 mol) of biphenol (BP), 6,500 g (39.6 mol) of terephthalic acid (TPA), and 1,570 g (10.4 mol) of hydroxyacetanilide (APAP) were added. Then, 12,300 g (120.5 mol) of acetic anhydride was added, and these were mixed in the batch reactor.

[0054] 2. 2.7 g of potassium acetate catalyst and 10.8 g of magnesium acetate catalyst were added, and nitrogen was injected to inert the internal space of the reactor.

[0055] 3. The reactor temperature was raised over 1 hour to a temperature at which the acetic anhydride inside the batch reactor refluxed. At this temperature, the hydroxyl groups of each monomer were acetylated over 2 hours, and the acetic acid produced by the acetylation reaction and the excess unreacted acetic anhydride were removed. The reactor temperature was raised to 320°C at a rate of 0.5°C / min to produce a liquid crystal polyester prepolymer. After that, it was cooled and solidified while being discharged through the lower valve, and pulverized to obtain 32,000 g of liquid crystal polyester prepolymer.

[0056] 4. The liquid crystal polyester prepolymer was secondarily pulverized using a fine pulverizer and then placed in a rotary heating device. The rotary heating device was heated to 200°C over 2 hours while nitrogen was flowed through it at a flow rate of 25 L / min, and maintained at 200°C for 2 hours. After that, the temperature was raised to 285°C at a rate of 0.2°C / min and maintained for 3 hours while carrying out the polycondensation reaction.

[0057] 5. After the polycondensation reaction, a liquid crystal polyester resin was finally obtained, and the melting point of the manufactured resin was 330°C.

[0058] Example 1. Production of a liquid crystal polyester resin composition

[0059] 1. A mixture of 75% by weight of liquid crystal polyester resin (hereinafter referred to as LCP resin) produced in the manufacturing example, 3% by weight of carbon black, 8% by weight of mica, 10% by weight of glass powder, and 4% by weight of PPS resin was prepared. The components used are specifically shown in Table 1 below.

[0060] 2. The material was melted and kneaded in a twin-screw extruder (L / D: 44, diameter: 30 mm). The barrel temperature of the extruder during melting and kneading was 340°C. By-products were removed by passing the material through a vacuum before it was pelletized.

[0061] 3. The pelletized liquid crystal polyester resin composition was mixed for 30 minutes using a mixer (Daiichi Sangyo Kiki, JITD-50KW), and then dried at 150°C for 2 hours using a hot air dryer (Daiichi Sangyo Kiki, JIB-100KW).

[0062] [Table 1]

[0063] Preparation of the liquid crystal polyester resin compositions of Examples 2 to 5

[0064] The liquid crystal polyester resin compositions of Examples 2 to 5 were manufactured using the same method as in Example 1, according to the composition ratios shown in Table 2 below.

[0065] Production of the liquid crystal polyester resin compositions of Comparative Examples 1 to 4

[0066] The liquid crystal polyester resin compositions of Comparative Examples 1 to 4 were manufactured using the same method as in Example 1, with the components and compositional ratios listed in Table 2 below.

[0067] [Table 2]

[0068] Test Example 1. Tensile strength of liquid crystal polyester resin composition

[0069] For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, test specimens measuring 19 mm in width, 130 mm in length, and 3.2 mm in thickness were prepared.

[0070] The tensile strength of each manufactured test specimen was evaluated according to ASTM D638, and the results are shown in Table 3.

[0071] Test Example 2. Impact strength of liquid crystal polyester resin composition

[0072] For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, test specimens measuring 12.7 mm in width, 64 mm in length, and 3.2 mm in thickness were prepared.

[0073] The impact strength of each manufactured test specimen was evaluated in an unnotched state according to ASTM D256, and the results are shown in Table 3.

[0074] Test Example 3. Shrinkage Rate of Liquid Crystal Polyester Resin Composition

[0075] For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, test specimens measuring 12.4 mm in width, 80 mm in length, and 3 mm in thickness were manufactured by injection molding, and then left in a constant temperature and humidity chamber at 50% humidity and 23°C for one day.

[0076] The shrinkage rates in the MD and TD directions were measured for the manufactured test specimens, and the results are shown in Table 3.

[0077] Test Example 4. Weld line impact strength of liquid crystal polyester resin composition

[0078] For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, test specimens measuring 12.4 mm in width, 80 mm in length, and 3 mm in thickness were prepared. During the preparation of the test specimens, the gates from which the resin composition was extruded were positioned in both directions, so that the resin met at the center of the test specimen from both ends, thereby creating a weld line.

[0079] The weld line impact strength was measured by applying impact to each weld line portion of each manufactured test specimen using an IZOD impactor in an unnotched state according to ASTM D256, and the results are shown in Table 3.

[0080] Test Example 5. Fibril Evaluation of Liquid Crystal Polyester Resin Compositions

[0081] 1. For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, test specimens measuring 12.4 mm in width, 80 mm in length, and 3 mm in thickness were injected and then conditioned in a constant temperature and humidity chamber at 50% humidity and 23°C for a minimum of 8 hours.

[0082] 2. Each test specimen was washed at room temperature using a 40kHz ultrasonic cleaner with a 1% alkaline aqueous solution for 8 minutes, then with ultrapure water for 2 minutes, and finally dried in an 80°C oven for 30 minutes.

[0083] 3. After blowing air at room temperature for 10 seconds, the presence or absence of fibrils was observed using an optical microscope (HIROX, XY-GB2).

[0084] 4. For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, 100 test specimens were measured.

[0085] 5. After going through the above 1 to 4 processes, Table 3 shows the number of test specimens in which fibrils were generated out of 100 test specimens.

[0086] Test Example 6. Tape Test of Liquid Crystal Polyester Resin Composition

[0087] 1. For each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4, test specimens measuring 12.7 mm in width, 130 mm in length, and 3.2 mm in thickness were manufactured by injection molding.

[0088] 2. The surface of each test specimen was washed with ethanol and allowed to air dry for about 10 minutes.

[0089] 3. Each test specimen should have 12.7 cm 2 A piece of tape (3M Scotch Magic Tape 810) with an area of ​​12.7mm wide and 100mm long was applied.

[0090] 4. Using a weight of approximately 3.7 kg, the area to which the tape was attached was pressed five times, and the pressed state was maintained for approximately 10 minutes.

[0091] 5. A weight of approximately 2.6 kg was attached to the tape that was adhered to each test specimen, and the weight was allowed to free-fall, separating the adhesive tape from each test specimen.

[0092] 6. The area of ​​the black resin composition attached to the peeled tape was observed under a microscope and calculated, and the results are shown in Table 3.

[0093] Test Example 7. Dent evaluation of liquid crystal polyester resin composition

[0094] 1. Test specimens measuring 12.4 mm in width, 80 mm in length, and 3 mm in thickness were prepared by molding each of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4 using an injection molding machine.

[0095] 2. Each manufactured test specimen was mounted on a dust simulation test machine, and a 15g ball was dropped from a height of 15cm 70 times consecutively.

[0096] 3. After the continuous drop test, the dent depth (μm) and dent volume (μm) of each specimen were measured using 3D tiling techniques via an optical microscope (HIROX, XY-GB2). 3 ) was measured.

[0097] 4.1 Processes 1 through 3 are combined into one test, and performed a total of four times for each specimen. The dent depth (μm) and dent volume (μm) of each specimen are measured. 3 The average values ​​for ) are shown in Table 3.

[0098] [Table 3]

[0099] The liquid crystal polyester resin compositions of Examples 1 to 5 have a tensile strength of 100 MPa or more and a strength of 80 kJ / m 2 The above impact strength confirms that the composition possesses excellent mechanical properties. Furthermore, it can be concluded that the liquid crystal polyester resin compositions of Examples 1 to 5 have resistance to internal and external impacts and the ability to suppress dust generation, and that they have stability against external or internal impacts and friction. In comparison, Comparative Example 2 showed poor tensile strength and impact strength. This is considered to be because the composition of Comparative Example 2 contained an excessive amount of PPS resin, which reduced its compatibility with the LCP resin, resulting in poor tensile strength and impact strength.

[0100] The liquid crystal polyester resin compositions of Examples 1 to 5 showed a shrinkage rate in the MD direction of less than 0.08% and a shrinkage rate in the TD direction of less than 1.13%. On the other hand, in the case of Comparative Example 2, it showed a shrinkage rate in the MD direction of about 0.08%, and in the cases of Comparative Examples 1 and 4, it showed a shrinkage rate in the TD direction of about 1.13% or more. In the cases of Comparative Examples 1 and 2, although they do not contain PPS resin, it is considered that the above results appeared due to excessive content. In the case of Comparative Example 4, since it does not contain inorganic fillers other than glass powder and contains an excessive amount of glass powder, it is expected that the above results appeared.

[0101] Since the liquid crystal polyester resin compositions of Examples 1 to 5 have a weld line impact strength exceeding 20 J / m, they have excellent weld line impact strength, resistance to internal and external impacts, and the possibility of suppressing dust generation, and it was confirmed that they have stability against external or internal impacts and friction. On the other hand, in the cases of Comparative Examples 1 and 3, since they have a poor weld line impact strength of 20 J / m or less, it was confirmed that there is a possibility that the molded products are easily damaged by internal and external impacts. This is considered to be due to the fact that Comparative Example 1 does not contain PPS resin and Comparative Example 3 does not contain glass powder.

[0102] The area peeled off at the portion where the tape was adhered in the test piece of the liquid crystal polyester resin composition of Example 4 was 1.69 cm 2 , showing the largest peeled area among the examples, and the peeled area was less than about 15% of the area of the test piece adhered to the tape (12.7 cm 2 ). Also, for the liquid crystal polyester resin compositions of Examples 1 to 3 and Example 5, the area peeled off by the tape test was 0.79 cm 2 to 1.16 cm 2 , and it was peeled off in the range of about 5% or more to less than 10% of the area of the test piece adhered to the tape. In comparison with this, in the case of Comparative Example 3, an area of about 10.48 cm 2 was peeled off, and about 83% of the area of the test piece adhered to the tape was peeled off. In the case of Comparative Example 3, since it does not contain glass powder, it is considered that peeling against the tape has become quite significant.

[0103] In all of the liquid crystal polyester resin compositions of Examples 1 to 5, fibril was observed in 31 or fewer out of 100 test pieces. However, in Comparative Example 1, fibril was observed in 75 test pieces. In this case, it is considered that Comparative Example 1, which does not contain PPS resin and is composed only of LCP resin, exhibited fibril in a large number of test pieces.

[0104] The liquid crystal polyester resin compositions of Examples 1 to 5 all have a dent depth of less than approximately 30 μm and a dent volume of approximately 14,600,000 μm. 3 The following was confirmed: On the other hand, the dent depth of Comparative Example 2 exceeded 30 μm, and the dent volume of Comparative Examples 2 to 4 was 14,600,000 μm. 3 The value was exceeded. In the case of Comparative Example 2, it is considered that the poor dent characteristics were due to the inclusion of an excessive amount of PPS resin; in the case of Comparative Example 3, it was due to the absence of glass powder; and in the case of Comparative Example 4, it was considered that the poor dent characteristics were due to the absence of inorganic fillers other than glass powder and the excessive use of glass powder.

[0105] The present invention is not limited to the embodiments described above, and it is obvious to those with ordinary skill in the art to which the present invention pertains that it can be implemented in various ways by modification or alteration without departing from the technical spirit of the invention.

Claims

1. A liquid crystal polyester resin of 55% by weight or more and 85% by weight or less; Polyphenylene sulfide resin containing 1% by weight or more and less than 15% by weight; Carbon-based fillers in an amount of 1% by weight or more and 5% by weight or less; and It includes an inorganic filler in an amount of 5% by weight or more and 30% by weight or less; The inorganic filler is a liquid crystal polyester resin composition comprising glass powder and a plate-like filler, A liquid crystal polyester resin composition wherein the molded product produced from the liquid crystal polyester resin composition has a weld line impact strength exceeding 20 J / m and a dent volume of 14,600,000 μm³ or less.

2. The glass powder is 1% by weight or more and less than 18% by weight; and The plate-shaped filler is 4% by weight or more and 17% by weight or less. The liquid crystal polyester resin composition according to claim 1, comprising the above.

3. The liquid crystal polyester resin composition according to claim 1, wherein the carbon-based filler is one or more selected from the group consisting of carbon black, graphite, and carbon nanotubes.

4. The inorganic fillers include silica, quartz powder, glass bead, calcium silicate, aluminum silicate, kaolin, clay, diatomaceous earth, wollastonite, iron oxide, titanium oxide, zinc oxide, alumina, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, silicon carbide, silicon nitride, boron nitride, potassium titanate, and molybdenum disulfide (MoS ２ The liquid crystal polyester resin composition according to claim 1, further comprising one or more selected from the group consisting of ).

5. The liquid crystal polyester resin composition according to claim 1, wherein the dent depth of the molded article produced from the liquid crystal polyester resin composition is less than 30 μm.

6. A liquid crystal polyester resin of 55% by weight or more and 85% by weight or less; Polyphenylene sulfide resin containing 1% by weight or more and less than 15% by weight; Carbon-based fillers in an amount of 1% by weight or more and 5% by weight or less; and A liquid crystal polyester resin composition comprising 5% by weight or more and 30% by weight or less of an inorganic filler, When a tape is applied to a test piece made from the aforementioned liquid crystal polyester resin composition and then peeled off, the peeled area is less than 15% of the area of ​​the test piece to which the tape was applied. A liquid crystal polyester resin composition wherein the dent volume of a molded article produced from the liquid crystal polyester resin composition is 14,600,000 μm³ or less.

7. A molded article manufactured from a liquid crystal polyester resin composition according to claim 1.

8. An electronic component material comprising a liquid crystal polyester resin composition according to claim 1.

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