CN115279832A

CN115279832A - Resin composition and resin molded article comprising the same

Info

Publication number: CN115279832A
Application number: CN202180021352.3A
Authority: CN
Inventors: 大野希望; 梅村雄二
Original assignee: Eneos Corp
Current assignee: Eneos Corp
Priority date: 2020-03-18
Filing date: 2021-03-15
Publication date: 2022-11-01
Also published as: TW202140670A; WO2021187399A1; JP2021147476A

Abstract

The present invention provides a resin composition which has melt-moldability and heat resistance comparable to those of liquid crystal polyester resins, and which has a low dielectric loss tangent and a low dielectric constant. The resin composition of the present invention is characterized by comprising: a liquid crystal polyester resin (A) comprising a hydroxycarboxylic acid-derived constituent unit (I), a diol compound-derived constituent unit (II) and a dicarboxylic acid-derived constituent unit (III), a fluororesin (B) and an inorganic hollow filler (C), and a method for measuring the frequency of a cavity resonator at 10GHzDielectric loss tangent of 2.0X 10 measured by perturbation method^‑3The relative dielectric constant is 3.50 or less.

Description

Resin composition and resin molded article comprising the same

Technical Field

The present invention relates to a resin composition having a low dielectric loss tangent and a low dielectric constant. The present invention also relates to a resin molded article made of the resin composition, and an electrical and electronic component provided with the resin molded article.

Background

In recent years, with the increase in the amount of information communication in the field of communications, the use of signals having a high-frequency band frequency in electronic devices, communication devices, and the like has increased, and in particular, the use of signals having a frequency of 10 is actively being used⁹Gigahertz (GHz) band frequencies above Hz. However, as the frequency of the signal used becomes higher, the quality of the output signal whose information is erroneously recognized may be degraded, that is, the transmission loss becomes larger. The transmission loss includes a conductor loss due to a conductor and a dielectric loss due to an insulating resin composition constituting an electric and electronic component such as a substrate in an electronic device or a communication device, and the conductor loss is proportional to the 0.5 th power of a frequency to be used and the dielectric loss is proportional to the 1 st power of the frequency, and therefore, the influence of the dielectric loss is very large in a high frequency band, particularly, a GHz band. In addition, since the dielectric loss also increases in proportion to the dielectric loss tangent and the dielectric constant of the resin composition, a resin composition having a low dielectric loss tangent and a low dielectric constant is required to prevent deterioration of information.

In addition, since liquid crystal polyester resins have excellent moldability and heat resistance, resin molded articles (e.g., injection molded articles) produced using the liquid crystal polyester resins are used for various electronic parts. In recent years, electronic parts have been increasingly integrated, thinned, and reduced in height due to miniaturization of personal computers, smart phones, and the like, and there has been an increasing demand for molded products having an extremely thin thick portion. In addition, liquid crystal polyester resins are thermoplastic resins having both low viscosity and high heat resistance, and have attracted attention because they have a dielectric loss tangent of one digit smaller than that of insulating materials for substrates such as polyimide. In order to satisfy such social demands, the present applicant has proposed a liquid crystal polyester resin having a low dielectric loss tangent (see patent document 1).

In order to further reduce the dielectric loss tangent of a liquid crystal polyester resin, it has been proposed to blend a hollow glass bead filler having an air layer with a dielectric constant of 1 into the liquid crystal polyester resin (see patent document 2). Since air has an extremely low dielectric constant such as a dielectric constant of 1, it can be mixed with a resin to lower the dielectric constant. However, the glass ball filler has a problem that the dielectric constant is lowered, but the dielectric loss tangent is increased (deteriorated), and thus the electrical characteristics cannot be effectively improved.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 6434195

Patent document 2: japanese patent laid-open publication No. 2004-27021

Disclosure of Invention

Accordingly, an object of the present invention is to provide a resin composition having necessary heat resistance, a low dielectric loss tangent and a low dielectric constant. Another object of the present invention is to provide a resin molded article made of such a resin composition.

The present inventors have conducted intensive studies in order to solve the above problems, and as a result, have found that the above problems can be solved by adjusting the dielectric loss tangent and the relative permittivity of a resin composition in which a specific liquid crystal polyester resin (a), a fluororesin (B) and an inorganic hollow filler (C) are mixed to fall within specific numerical ranges. The present invention has been completed based on this finding.

That is, according to one embodiment of the present invention, there is provided a resin composition comprising:

a liquid crystal polyester resin (A) comprising a hydroxycarboxylic acid-derived constituent unit (I), a diol compound-derived constituent unit (II), and a dicarboxylic acid-derived constituent unit (III);

the dielectric loss tangent of the resin composition measured by a cavity resonator perturbation method at a frequency of 10GHz was 2X 10^-3The relative dielectric constant is 3.50 or less.

In an embodiment of the present invention, the melting point of the liquid crystal polyester resin (a) is preferably 280 ℃ or higher.

In an embodiment of the present invention, the dielectric loss tangent of the liquid crystal polyester resin (A) measured by a 10GHz cavity resonator perturbation method is preferably 1.00X 10^-3The following.

In an embodiment of the present invention, the resin (B) preferably contains a polytetrafluoroethylene resin.

In an embodiment of the present invention, the amount of the liquid crystal polyester resin (a) is preferably 30 parts by mass or more and 98 parts by mass or less, the amount of the fluororesin (B) is preferably 1 part by mass or more and 50 parts by mass or less, and the amount of the inorganic hollow filler (C) is preferably 1 part by mass or more and 30 parts by mass or less, with respect to 100 parts by mass of the total of the liquid crystal polyester resin (a), the fluororesin (B), and the inorganic hollow filler (C).

In an embodiment of the present invention, the constituent unit (I) derived from a hydroxycarboxylic acid is preferably a constituent unit derived from 6-hydroxy-2-naphthoic acid.

In an embodiment of the present invention, the composition ratio of the constituent unit (I) is preferably 30 mol% or more and 80 mol% or less with respect to the entire constituent unit of the liquid crystal polyester resin (a).

In an embodiment of the present invention, the constituent unit (II) derived from a diol compound is preferably at least 1 constituent unit derived from 4, 4-dihydroxybiphenyl, hydroquinone, methyl hydroquinone, and 4,4' -isopropylidenediphenol.

In an embodiment of the present invention, the constituent unit (III) derived from a dicarboxylic acid is preferably a constituent unit derived from at least 1 selected from the group consisting of terephthalic acid, isophthalic acid, and 2, 6-naphthalenedicarboxylic acid.

According to another aspect of the present invention, there is provided a resin molded article comprising the resin composition.

According to still another aspect of the present invention, there is provided an electric/electronic component including the resin molded article.

According to the present invention, a resin composition having a low dielectric loss tangent and a low dielectric constant while having necessary heat resistance can be obtained. Further, by using such a resin composition, a resin molded article having necessary heat resistance, a low dielectric loss tangent and a low dielectric constant can be obtained.

Further, although the electronic component is reduced in thickness, warpage is likely to occur during the reflow step, and a problem arises due to the occurrence of defects, the resin molded article of the present invention can also suppress the occurrence of warpage during heating at a high temperature in the reflow step or the like.

Drawings

Fig. 1 is a plan view and a side view of a molded article for measuring warpage produced in an example.

Detailed Description

[ resin composition ]

The resin composition of the present invention comprises the following liquid crystal polyester resin (a), fluororesin (B) and inorganic hollow filler (C), has required heat resistance, and has a low dielectric loss tangent and a low dielectric constant. By using such a resin composition, a resin molded article having excellent heat resistance, a low dielectric loss tangent and a low dielectric constant can be obtained.

The dielectric loss tangent of the resin composition as measured by a cavity resonator perturbation method at 10GHz was 2.0X 10^-3Hereinafter, it is preferably 1.9X 10^-3Hereinafter, more preferably 1.8 × 10^-3The following.

The resin composition has a relative dielectric constant of 3.50 or less, preferably 3.40 or less, as measured by a 10GHz cavity resonator perturbation method.

This value is a measured value of the flow direction of the injection-molded article of the resin composition. The injection-molded article was a test piece cut out from a flat plate of 60mm × 60mm × 0.8mm (thickness) to a width of 60mm × 3 mm.

In the present specification, the dielectric loss tangent at 10GHz of the resin composition can be measured by a cavity resonator perturbation method using a network analyzer from anli corporation and a resonator from AET corporation. In addition, when not specified, the value of the dielectric loss tangent was 23 ℃ and the value measured in the atmosphere.

Hereinafter, each component contained in the resin composition will be described.

(liquid Crystal polyester resin (A))

The liquid crystal polyester resin used in the resin composition of the present invention contains a constituent unit (I) derived from a hydroxycarboxylic acid, a constituent unit (II) derived from a diol compound, and a constituent unit (III) derived from a dicarboxylic acid. Hereinafter, each constituent unit contained in the liquid crystal polyester resin will be described.

(constituent Unit (I) derived from hydroxycarboxylic acid)

The unit (I) constituting the liquid crystal polyester resin (a) is a constitutional unit derived from a hydroxycarboxylic acid, and is preferably a constitutional unit derived from an aromatic hydroxycarboxylic acid represented by the following formula (I). The constituent unit (I) may include only 1 species, or may include 2 or more species.

In the above formula, ar¹Selected from the group consisting of phenyl, biphenyl, 4' -isopropylidenediphenyl, naphthyl, anthryl and phenanthryl, which may have a substituent as required. Among these, preferred are phenyl, biphenyl and naphthyl, and more preferred is naphthyl. Examples of the substituent include hydrogen, alkyl, alkoxy, and fluorine. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 5. The alkyl group may be a linear alkyl group or a branched alkyl group. The number of carbon atoms of the alkoxy group is preferably 1 to 10, more preferably 1 to 5.

Examples of the monomer to which the structural unit represented by the formula (I) is added include 6-hydroxy-2-naphthoic acid (HNA, formula (1)) and p-hydroxybenzoic acid (HBA, formula (2)) and acylates, ester derivatives, and acid halides thereof.

The lower limit of the composition ratio (mol%) of the constituent unit (I) to the constituent unit of the entire polyester resin is preferably 30 mol% or more, more preferably 35 mol% or more, further preferably 40 mol% or more, further more preferably 45 mol% or more, and the upper limit thereof is preferably 80 mol% or less, more preferably 75 mol% or less, further preferably 70 mol% or less, and further more preferably 65 mol% or less. When 2 or more kinds of the constituent unit (I) are contained, the total molar ratio thereof may be within the above composition ratio. It should be noted that the composition ratio of the constituent unit derived from 6-hydroxy-2-naphthoic acid is preferably larger than the composition ratio of the constituent unit derived from p-hydroxybenzoic acid as the constituent unit (I). When 2 or more kinds of the constituent units (I) are contained, the composition ratio of the constituent unit derived from 6-hydroxy-2-naphthoic acid is preferably more than 50 mol%, more preferably 70 mol% or more, and further preferably 90 mol% or more of the total of the constituent units (I).

(constituent Unit (II) derived from diol Compound)

The unit (II) constituting the liquid crystal polyester resin (a) is a constituent unit derived from a diol compound, and is preferably a constituent unit derived from an aromatic diol compound represented by the following formula (II). The constituent unit (II) may include only 1 species, or may include 2 or more species.

In the above formula, ar²Selected from the group consisting of phenyl, biphenyl, 4' -isopropylidenediphenyl, naphthyl, anthryl and phenanthryl, which may have a substituent as required. Among these, phenyl and biphenyl are more preferable. Examples of the substituent include hydrogen, alkyl, alkoxy, and fluorine. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 5. The alkyl group may be a linear alkyl group or a branched alkyl group. The alkoxyl group preferably has 1 to 10 carbon atoms, more preferably 1 to up to5。

Examples of the monomer to be added to the constituent unit (II) include 4, 4-dihydroxybiphenyl (BP, the following formula (3)), hydroquinone (HQ, the following formula (4)), methylhydroquinone (MeHQ, the following formula (5)), 4' -isopropylidenediphenol (BisPA, the following formula (6)), and acylates, ester derivatives, acid halides thereof, and the like. Among these, 4-dihydroxybiphenyl (BP) and its acylates, ester derivatives, and acid halides are preferably used.

The lower limit of the composition ratio (% by mole) of the constituent unit (II) to the total constituent units of the polyester resin is preferably 10% by mole or more, more preferably 12.5% by mole or more, further preferably 15% by mole or more, further more preferably 17.5% by mole or more, and the upper limit thereof is preferably 35% by mole or less, more preferably 32.5% by mole or less, further preferably 30% by mole or less, and further more preferably 27.5% by mole or less. When 2 or more kinds of the constituent unit (II) are contained, the total molar ratio thereof may be within the above range of the composition ratio.

(constituent Unit (III) derived from aromatic dicarboxylic acid)

The unit (III) constituting the liquid crystal polyester resin (a) is a dicarboxylic acid-derived constituent unit, and is preferably an aromatic dicarboxylic acid-derived constituent unit represented by the following formula (III). The constituent unit (III) may include only 1 species, or may include 2 or more species.

In the above formula, ar³Selected from the group consisting of phenyl, biphenyl, 4' -isopropylidenediphenyl, naphthyl, anthryl and phenanthryl, which may have a substituent as required. Among these, phenyl and biphenyl are more preferable. Examples of the substituent include hydrogen, alkyl, alkoxy, and fluorine. Having an alkyl groupThe number of carbon atoms is preferably 1 to 10, more preferably 1 to 5. The alkyl group may be a linear alkyl group or a branched alkyl group. The number of carbon atoms of the alkoxy group is preferably 1 to 10, more preferably 1 to 5.

Examples of the monomer to be added to the constituent unit (III) include terephthalic acid (TPA, the following formula (7)), isophthalic acid (IPA, the following formula (8)), 2, 6-naphthalenedicarboxylic acid (NADA, the following formula (9)), and acylates, ester derivatives, acid halides thereof, and the like.

The lower limit of the composition ratio (mol%) of the constituent unit (III) to the entire constituent units of the polyester resin (a) is preferably 5 mol% or more, more preferably 10 mol% or more, further preferably 12.5 mol% or more, further more preferably 15 mol% or more, particularly preferably 17.5 mol% or more, and the upper limit thereof is preferably 35 mol% or less, more preferably 32.5 mol% or less, further preferably 30 mol% or less, and further more preferably 27.5 mol% or less. When 2 or more kinds of the constituent unit (II) are contained, the total molar ratio thereof may be within the above composition ratio. The composition ratio of the constituent unit (II) substantially corresponds to the composition ratio of the constituent unit (III) (the constituent unit (II) ≈ the constituent unit (III)).

As a particularly preferable blending of the polyester resin (a) of the present invention, the content of at least the constituent unit of 6-hydroxy-2-naphthoic acid is in the range of 45 mol% or more and 75 mol% or less with respect to the whole constituent unit of the polyester resin (a). Particularly preferred compounding of the polyester resin (a) is as follows:

45 mol% or more and 75 mol% or less of a constituent unit (I) derived from 6-hydroxy-2-naphthoic acid

12 mol% or more and 27.5 mol% or less of a constituent unit (II) derived from an aromatic diol compound

3 mol% or more and 25 mol% or less of constituent unit (III) derived from terephthalic acid

2 mol% or more and 9 mol% or less of a constituent unit (III) derived from 2, 6-naphthalenedicarboxylic acid.

When the respective constituent units are within the above ranges relative to the whole constituent units of the polyester resin (A), a polyester resin having a low dielectric loss tangent can be obtained.

The liquid crystallinity of the liquid-crystalline polyester resin (a) can be confirmed by: the liquid crystal polyester resin (A) was heated and melted on a microscope heating stage using a polarizing microscope (trade name: BH-2) manufactured by Olympus corporation equipped with a microscope stage (trade name: FP82 HT) manufactured by Mettler, and the presence or absence of optical anisotropy was observed.

The lower limit of the melting point of the liquid crystal polyester resin (a) is preferably 280 ℃ or higher, more preferably 290 ℃ or higher, further preferably 300 ℃ or higher, and further more preferably 305 ℃ or higher. The upper limit is preferably 370 ℃ or lower, more preferably 360 ℃ or lower, even more preferably 355 ℃ or lower, and even more preferably 350 ℃ or lower. When the melting point of the liquid crystal polyester resin (a) is in the above numerical range, the processing stability of the resin composition containing the liquid crystal polyester resin (a) in the range shown in the present invention, specifically, the stability of melt processability with shear and the melt processing stability in a state without shear can be improved, and the heat resistance of the material of the molded article produced using the liquid crystal polyester resin (a) can be maintained in a good range from the viewpoint of solder heat resistance.

The dielectric loss tangent of the liquid-crystalline polyester resin (A) measured by the cavity resonator perturbation method at 10GHz was 1.00X 10^-3Hereinafter, the preferable range is 0.95X 10^-3Hereinafter, more preferably 0.90 × 10^-3Hereinafter, it is more preferably 0.85 × 10^-3The following.

The liquid crystal polyester resin (a) has a relative dielectric constant of 3.7 or less, preferably 3.6 or less, as measured by a cavity resonator perturbation method at 10 GHz.

This value is a measured value of the flow direction of the injection-molded article of the liquid crystal polyester resin (a). The injection-molded article was a test piece obtained by cutting a flat test piece of 60mm × 60mm × 0.8mm (thickness) into 60mm × 3 mm.

In the resin composition of the present invention, the amount of the liquid crystal polyester resin (a) to be blended is preferably 30 parts by mass or more, more preferably 40 parts by mass or more, further preferably 45 parts by mass or more, further more preferably 50 parts by mass or more, and is preferably 98 parts by mass or less, more preferably 90 parts by mass or less, further preferably 85 parts by mass or less, as the lower limit, with respect to 100 parts by mass of the total of the liquid crystal polyester resin (a), the fluororesin (B), and the inorganic hollow filler (C). When the amount of the liquid crystal polyester resin (A) is about the above numerical range, a resin composition having a low dielectric loss tangent and a low dielectric constant while having necessary heat resistance can be obtained.

(method for producing liquid Crystal polyester resin (A))

The liquid crystal polyester resin (a) can be produced by polymerizing monomers, which are added to the constituent units (I) to (III) as needed, by a conventionally known method. In one embodiment, the wholly aromatic liquid crystalline polyester resin of the present invention may be produced by 2-stage polymerization of preparing a prepolymer by melt polymerization and further performing solid-phase polymerization of the prepolymer.

From the viewpoint of efficiently obtaining the polyester compound of the present invention, it is preferable that the monomers to which the constituent units (I) to (III) are added as necessary are mixed in a predetermined mixing ratio, and the mixture is melt-polymerized under reflux of acetic acid so that the 100 mol% of the mixture is present in an amount of 1.05 to 1.15 mol equivalent of acetic anhydride to all hydroxyl groups of the monomers.

In the case of carrying out the polymerization reaction in 2 stages of melt polymerization and subsequent solid-phase polymerization, it is preferable to select a known solid-phase polymerization method, for example, a method of subjecting a prepolymer resin to heat treatment at a temperature of 200 to 350 ℃ for 1 to 30 hours in an inert gas atmosphere such as nitrogen or in a vacuum after cooling and solidifying the prepolymer obtained by melt polymerization and then pulverizing the solidified prepolymer into a powder or a flake. The solid-phase polymerization may be carried out with stirring, or may be carried out in a state of being left without stirring.

The polymerization reaction may be carried out using a catalyst, or may not be carried out using a catalyst. As the catalyst to be used, conventionally known catalysts as a catalyst for polymerization of polyester can be used, and examples thereof include metal salt catalysts such as magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate, and antimony trioxide; and organic compound catalysts such as nitrogen-containing heterocyclic compounds such as N-methylimidazole. The amount of the catalyst used is not particularly limited, but is preferably 0.0001 to 0.1 part by weight based on 100 parts by weight of the total amount of the monomers.

The polymerization reaction apparatus in the melt polymerization is not particularly limited, and a reaction apparatus used for a reaction using a general high-viscosity fluid is preferably used. Examples of these reaction apparatuses include anchor type, multi-stage type, spiral belt type, spiral shaft type, and the like, or a stirring tank type polymerization reaction apparatus having a stirring device with stirring blades of various shapes formed by deforming them; or a mixing device generally used for kneading a resin, such as a kneader, roll mill, or banbury mixer.

(fluororesin (B))

In the present invention, the fluororesin (B) is a synthetic resin obtained by polymerizing an olefin containing fluorine, and refers to all of a fully fluorinated resin, a partially fluorinated resin, and a copolymer of a fluoride. In the present invention, these fluororesins are preferably used in the form of powder. The average particle size of the powdery fluororesin is preferably 0.5 to 70 μm. The average particle size means a volume average particle size, and can be measured by a laser diffraction method.

Specific examples of the fluororesin (B) include polytetrafluoroethylene resin (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA), tetrafluoroethylene-hexafluoropropylene copolymer resin (FEP), polychlorotrifluoroethylene resin (PCTFE), ethylene-tetrafluoroethylene copolymer resin (ETFE), ethylene-chlorotrifluoroethylene copolymer resin (ECTFE), polyvinyl fluoride resin (PVF), tetrafluoroethylene-perfluoroalkyl vinyl ether-hexafluoropropylene copolymer resin (EPE), and the like. Among these, polytetrafluoroethylene resin (PTFE) is preferably used. The fluorine resin (B) may be used in only 1 kind, or may be used in 2 or more kinds. The fluororesin (B) of the present invention preferably has a lower dielectric loss tangent than the liquid crystal polyester resin (a).

In the resin composition of the present invention, the amount of the fluororesin (B) to be blended is preferably 1 part by mass or more as a lower limit value, more preferably 3 parts by mass or more, and further preferably 5 parts by mass or more, and is preferably 50 parts by mass or less, more preferably 45 parts by mass or less, further preferably 40 parts by mass or less, and further more preferably 35 parts by mass or less, relative to 100 parts by mass of the total of the liquid crystal polyester resin (a), the fluororesin (B), and the inorganic hollow filler (C). When the amount of the fluororesin (B) is about the above numerical range, a resin composition having a low dielectric loss tangent and a low dielectric constant while having necessary heat resistance can be obtained.

(inorganic hollow Filler (C))

In the present invention, the inorganic hollow filler (C) is a filler for hollow bodies containing an inorganic component as a main component. Here, the hollow body includes not only a filler having a single hollow portion inside the filler, but also a filler having a plurality of bubbles inside, and a filler such as pumice having an inner foam communicating with the outside. The average particle diameter of the inorganic hollow filler (C) is preferably 0.5 to 100. Mu.m, more preferably 1 to 80 μm, and still more preferably 5 to 50 μm. The average particle size means a volume average particle size, and can be measured by a laser diffraction method.

Specific examples of the inorganic hollow filler (C) include hollow bodies made of inorganic materials such as glass, alumina, silica, zirconia, magnesia, white sand, fly ash, borate, phosphate, and ceramics. When these inorganic hollow fillers are dispersed in a resin molded article, the resin molded article contains fine bubbles in appearance, and the relative dielectric constant is lowered. These inorganic hollow fillers are preferably high in strength because they may be damaged by the history of stress in the production process of the composition and the production process of the resin molded article.

In the resin composition of the present invention, the amount of the inorganic hollow filler (C) to be blended is preferably 1 part by mass or more, more preferably 2 parts by mass or more, further preferably 3 parts by mass or more, further more preferably 5 parts by mass or more, and is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, further preferably 15 parts by mass or less, further more preferably 12 parts by mass or less, as the lower limit, relative to 100 parts by mass of the total of the liquid crystal polyester resin (a), the fluororesin (B), and the inorganic hollow filler (C). When the amount of the inorganic hollow filler (C) is about the above numerical range, a resin composition having a low dielectric loss tangent and a low dielectric constant while having necessary heat resistance can be obtained.

(other additives)

The resin composition of the present invention may further contain other additives such as a colorant, a dispersant, a plasticizer, an antioxidant, a curing agent, a flame retardant, a heat stabilizer, an ultraviolet absorber, an antistatic agent, a surfactant, within a range not to impair the effects of the present invention.

The amount of the additive to be blended in the resin composition is preferably 0.01 parts by mass or more, more preferably 0.5 parts by mass or more as the lower limit, and preferably 5 parts by mass or less, more preferably 1 part by mass or less as the upper limit, per 100 parts by mass of the total of the liquid crystal polyester resin (a), the fluororesin (B) and the inorganic hollow filler (C).

(resin molded article)

The resin molded article of the present invention is composed of the above resin composition. The resin molded article of the present invention has required heat resistance, and has a low dielectric loss tangent and a low dielectric constant.

(method for producing resin molded article)

In the present invention, the resin composition containing the liquid crystal polyester resin (a), the fluororesin (B), the inorganic hollow filler (C), and other additives as needed can be molded by a conventionally known method. The resin composition can be obtained by melt-kneading the liquid crystal polyester resin (a), the fluororesin (B), the inorganic hollow filler (C), and the like using a banbury mixer, a kneader, a uniaxial or biaxial extruder, or the like.

Examples of the molding method include press molding, foam molding, injection molding, extrusion molding, and punching molding. The molded article produced in the above manner can be processed into various shapes according to the use. The shape of the molded article may be, for example, a plate shape, a film shape, or the like.

(electric and electronic parts)

The electric and electronic component of the present invention comprises the above resin composition. Examples of the electric and electronic components include electronic devices such as ETC, GPS, wireless LAN, and cellular phone, antennas used in communication devices, high-speed transmission connectors, CPU sockets, circuit boards, flexible printed circuit boards (FPC), circuit boards for lamination, millimeter wave and quasi-millimeter wave radars such as anti-collision radars, RFID tags, capacitors, inverter components, insulating films, covering materials for cables, insulating materials for secondary batteries such as lithium ion batteries, and speaker diaphragms.

Examples

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples.

< production of liquid Crystal polyester resin (A) >

(Synthesis example 1)

60 mol% of 6-hydroxy-2-naphthoic acid (HNA), 20 mol% of 4, 4-dihydroxybiphenyl (BP), 15.5 mol% of terephthalic acid (TPA), and 4.5 mol% of 2, 6-naphthalenedicarboxylic acid (NADA) were charged into a polymerization vessel having a stirring blade, potassium acetate and magnesium acetate were charged as catalysts, and after 3 times of reduced pressure-nitrogen injection to perform nitrogen substitution, acetic anhydride (1.08 molar equivalents with respect to the hydroxyl group) was further added to the polymerization vessel, and the temperature was raised to 150 ℃ to perform acetylation reaction under reflux for 2 hours.

After the completion of acetylation, the temperature of the polymerization vessel in the acetic acid distilled state was raised at 0.5 ℃ per minute, and when the temperature of the melt in the vessel reached 310 ℃, the polymer was taken out and cooled to solidify. The obtained polymer was pulverized and then pulverized into a size of passing through a sieve having a mesh of 2.0mm to obtain a prepolymer.

Then, the prepolymer obtained above was heated from room temperature to 300 ℃ for 7 hours in an oven manufactured by Yamato Scientific, and then, the temperature was maintained at 300 ℃ for 1 hour to perform solid phase polymerization. Then, the heat was released naturally at room temperature to obtain a liquid-crystalline polyester resin A1. A liquid crystal polyester resin sample was heated and melted on a microscope heating stage using a polarizing microscope (trade name: BH-2) manufactured by Olympus corporation equipped with a microscope stage (trade name: FP82 HT) manufactured by Mettler, and the liquid crystallinity was confirmed by the presence or absence of optical anisotropy.

(Synthesis example 2)

A liquid-crystalline polyester resin A2 was obtained in the same manner as in synthesis example 1, except that the monomer feed was changed to 60 mol% of HBA, 20 mol% of BP, 15 mol% of TPA, and 5 mol% of IPA, and the time for raising the temperature to 300 ℃ was changed to 14 hours. Next, it was confirmed that the obtained liquid crystal polyester resin A2 exhibited liquid crystallinity in the same manner as described above.

The constituent units (monomer compositions) of the liquid crystal polyester resins A1 to A2 obtained as described above are shown in table 1.

(measurement of melting Point)

The melting points of the liquid crystal polyester resins A1 to A2 obtained above were measured by a Differential Scanning Calorimeter (DSC) manufactured by Hitachi High-Tech Science, inc. according to the test method of ISO11357 and ASTM D3418. At this time, the temperature was raised from room temperature to 360 to 380 ℃ at a temperature raising rate of 10 ℃/min to completely melt the polymer, then the temperature was lowered to 30 ℃ at a rate of 10 ℃/min, and further raised to 380 ℃ at a rate of 10 ℃/min, and the peak of the endothermic peak obtained at this time was set as a melting point (Tm)₂). The measurement results are shown in table 1.

(measurement of dielectric loss tangent and relative dielectric constant (10 GHz))

The liquid crystal polyester resins A1 to A2 obtained above were heated and melted at the respective melting points to 30 ℃, and injection-molded using a mold of 60mm × 60mm × 0.8mm (thickness) to prepare flat test pieces. Next, the prepared flat test piece was cut into a 3mm width, and the relative permittivity and the dielectric loss tangent in the in-plane direction at a frequency of 10GHz were measured by the cavity resonator perturbation method using a network analyzer MS46122B manufactured by anli and a resonator manufactured by AET. Note that, each type of sample was measured with N =3, and the average value of 3 times is shown in table 1.

[ Table 1]

< preparation of fluororesin (B) >

The following resin was prepared as the fluororesin (B).

Polytetrafluoroethylene resin (PTFE): manufactured by Xiduocun corporation, trade name KT-400M

< preparation of inorganic hollow Filler (C) >

The following hollow filler was prepared as the inorganic hollow filler (C).

Hollow Glass (GB): manufactured by 3M company, trade name of S-60HS, average particle diameter of 24 μ M, true specific gravity of 0.60g/cm³

< preparation of other additives >

The following additives were prepared as other additives.

Milled fiber (MGF): manufactured by Central Glass Fiber corporation, trade name: EFH150-01

Mica: manufactured by Shankou mica, inc., trade name: AB-25S

< production of resin composition >

(example 1)

The obtained liquid crystal polyester resin A1 in 85 parts by mass, the polytetrafluoroethylene resin in 10 parts by mass, and the hollow glass in 5 parts by mass were dry blended, and then kneaded at a temperature of Tm2+20 to 50 ℃ of the liquid crystal polyester resin A1 with a biaxial kneader (manufactured by kubo corporation, PCM 30), and strand-cut and granulated, thereby obtaining a granular resin composition. The obtained resin composition was confirmed to have liquid crystallinity in the same manner as described above, and as a result, liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

(example 2)

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 75 parts by mass of the liquid-crystalline polyester resin A1 obtained above, 10 parts by mass of the polytetrafluoroethylene resin, and 15 parts by mass of the hollow glass were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

(example 3)

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 80 parts by mass of the liquid crystal polyester resin A1 obtained above, 10 parts by mass of the polytetrafluoroethylene resin, 5 parts by mass of the hollow glass, and 5 parts by mass of the milled fibers were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

(example 4)

A granular resin composition was produced in the same manner as in example 1, except that 80 parts by mass of the liquid crystal polyester resin A1 obtained above, 10 parts by mass of the polytetrafluoroethylene resin, 5 parts by mass of the hollow glass, and 5 parts by mass of the mica were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

(example 5)

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 75 parts by mass of the liquid crystal polyester resin A1 obtained above, 10 parts by mass of the polytetrafluoroethylene resin, 5 parts by mass of the hollow glass, 5 parts by mass of the mica, and 5 parts by mass of the milled fibers were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

(example 6)

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 75 parts by mass of the liquid crystal polyester resin A1 obtained above, 20 parts by mass of the polytetrafluoroethylene resin, and 5 parts by mass of the hollow glass were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

(example 7)

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 65 parts by mass of the liquid-crystalline polyester resin A1 obtained above, 30 parts by mass of the polytetrafluoroethylene resin, and 5 parts by mass of the hollow glass were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystalline polyester resin portion.

Comparative example 1

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 65 parts by mass of the liquid crystal polyester resin A1 obtained above and 35 parts by mass of the hollow glass were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

Comparative example 2

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 83 parts by mass of the liquid crystal polyester resin A2 obtained above, 12 parts by mass of the hollow glass, and 5 parts by mass of the milled fiber were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

Comparative example 3

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 75 parts by mass of the liquid crystal polyester resin A2 obtained above, 15 parts by mass of the mica, and 10 parts by mass of the milled fibers were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystal polyester resin portion.

Comparative example 4

A pellet-shaped resin composition was produced in the same manner as in example 1, except that 30 parts by mass of the liquid-crystalline polyester resin A1 obtained above, 65 parts by mass of the polytetrafluoroethylene resin, and 5 parts by mass of the hollow glass were kneaded. As a result, liquid crystallinity was confirmed in the same manner as described above, and liquid crystallinity was confirmed in the melted liquid crystalline polyester resin portion.

The composition of the resin composition obtained as described above is shown in table 2.

[ Table 2]

< measurement of dielectric loss tangent and relative dielectric constant (10 GHz) >

The pelletized resin compositions obtained in examples and comparative examples were heated and melted at a temperature of from the melting point to the melting point +30 ℃ by using a small injection molding machine, and were injection-molded by using a mold having a thickness of 60mm × 60mm × 0.8mm to prepare flat plate-like test pieces. Next, the prepared flat test piece was cut into a 3mm width, and the relative permittivity and the dielectric loss tangent in the flow direction at a frequency of 10GHz were measured by the cavity resonator perturbation method using a network analyzer MS46122B manufactured by anli and a resonator manufactured by AET. Note that, each kind of sample was measured with N =3, and the average value of 3 times is shown in table 3.

< measurement of deflection temperature under load >

The pelletized resin compositions obtained in the examples and comparative examples were injection molded by using an injection molding machine (SG-25, manufactured by Sumitomo heavy machinery industries, ltd.) at a cylinder maximum temperature of 360 ℃, an injection speed of 100mm/sec, and a mold temperature of 80 ℃ to prepare a bending test piece conforming to ASTM D790. Then, using the prepared test piece for the bending test, the deflection temperature under load (in ° c) was measured according to ASTM D648. The measurement results are shown in table 3.

< measurement of warpage >

The pelletized resin compositions obtained in the examples and comparative examples were molded by an injection molding machine (product name: LD10EH2, manufactured by Sodick) at a cylinder temperature of +10 ℃ for melting point, a mold temperature of 100 ℃ and an injection speed of 133mm/sec to obtain a box-shaped molded article shown in FIG. 1. The molded article obtained in the above manner was left in an air oven maintained at 260 ℃ for 10 minutes, and the warpage (warpage amount) of the bottom surface of the heated molded article was measured using One-shot 3D Macroscope (manufactured by Kinzhi Co., ltd., trade name: VR-3100). The results of the measurement are summarized in Table 3. The better the shape stability, the smaller the amount of warpage.

< influence of glass spheres on dielectric loss tangent >

In comparison between comparative example 1 and example 7, even when the total amount of the fluororesin and the glass beads blended in the liquid crystal polyester resin was the same, the dielectric loss tangent of the glass beads was higher than that of the polyester resin, and therefore, a significant increase in the dielectric loss tangent was observed even when the glass beads were used alone.

[ Table 3]

Claims

1. A resin composition comprising: a liquid crystal polyester resin (A) comprising a constituent unit (I) derived from a hydroxycarboxylic acid, a constituent unit (II) derived from a diol compound, and a constituent unit (III) derived from a dicarboxylic acid;

the resin composition has a dielectric loss tangent of 2.0X 10 as measured by a cavity resonator perturbation method at a frequency of 10GHz^-3The relative dielectric constant is 3.50 or less.

2. The resin composition according to claim 1, wherein the inorganic hollow filler (C) comprises a glass hollow filler.

3. The resin composition according to claim 1 or 2, wherein the melting point of the liquid-crystalline polyester resin (a) is 280 ℃ or higher.

4. Tree according to any one of claims 1 to 3A resin composition, wherein the liquid-crystalline polyester resin (A) has a dielectric loss tangent of 1.0X 10 as measured by 10GHz cavity resonator perturbation^-3The following.

5. The resin composition according to any one of claims 1 to 4, wherein the fluororesin (B) comprises a polytetrafluoroethylene resin.

6. The resin composition according to any one of claims 1 to 5, wherein the amount of the liquid crystal polyester resin (A) is 30 parts by mass or more and 98 parts by mass or less, the amount of the fluororesin (B) is 1 part by mass or more and 50 parts by mass or less, and the amount of the inorganic hollow filler (C) is 1 part by mass or more and 30 parts by mass or less, based on 100 parts by mass of the total of the liquid crystal polyester resin (A), the fluororesin (B), and the inorganic hollow filler (C).

7. The resin composition according to any one of claims 1 to 6, wherein the constituent unit (I) derived from a hydroxycarboxylic acid comprises a constituent unit derived from 6-hydroxy-2-naphthoic acid.

8. The resin composition according to any one of claims 1 to 7, wherein a composition ratio of the constituent unit (I) to the constituent unit of the entire liquid crystal polyester resin (A) is not less than 30 mol% and not more than 80 mol%.

9. The resin composition according to any one of claims 1 to 8, wherein the constituent unit (II) derived from a diol compound is a constituent unit derived from at least 1 selected from the group consisting of 4, 4-dihydroxybiphenyl, hydroquinone, methyl hydroquinone, and 4,4' -isopropylidenediphenol.

10. The resin composition according to any one of claims 1 to 9, wherein the constituent unit (III) derived from a dicarboxylic acid is a constituent unit derived from at least 1 selected from terephthalic acid, isophthalic acid, and 2, 6-naphthalenedicarboxylic acid.

11. A resin molded article comprising the resin composition according to any one of claims 1 to 10.

12. An electric/electronic component comprising the resin molded article according to claim 11.