CN113396180B - Liquid crystal polyester powder, liquid crystal polyester composition, method for producing film, and method for producing laminate - Google Patents

Liquid crystal polyester powder, liquid crystal polyester composition, method for producing film, and method for producing laminate Download PDF

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CN113396180B
CN113396180B CN202080012525.0A CN202080012525A CN113396180B CN 113396180 B CN113396180 B CN 113396180B CN 202080012525 A CN202080012525 A CN 202080012525A CN 113396180 B CN113396180 B CN 113396180B
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liquid crystal
crystal polyester
film
powder
liquid
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CN113396180A (en
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莇昌平
大友新治
伊藤豊诚
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Sumitomo Chemical Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
    • C08G63/60—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from the reaction of a mixture of hydroxy carboxylic acids, polycarboxylic acids and polyhydroxy compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
    • C08G69/44—Polyester-amides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
    • C08J5/18—Manufacture of films or sheets
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L69/00—Compositions of polycarbonates; Compositions of derivatives of polycarbonates
    • C08L69/005—Polyester-carbonates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L77/00—Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Compositions of derivatives of such polymers
    • C08L77/12—Polyester-amides

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  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Laminated Bodies (AREA)

Abstract

The liquid crystal polyester powder of the present invention comprises a liquid crystal polyester having a number average molecular weight of 10000 or less and has an average particle diameter of 0.5 to 20 [ mu ] m.

Description

Liquid crystal polyester powder, liquid crystal polyester composition, method for producing film, and method for producing laminate
Technical Field
The present invention relates to a liquid crystal polyester powder, a liquid crystal polyester composition, a method for producing a film, and a method for producing a laminate.
The present application claims priority based on japanese patent application No. 2019-025664 of the japanese application at 2 months 15 and japanese patent application No. 2019-141072 of the japanese application at 7 months 31, and the contents thereof are incorporated herein.
Background
In a printed circuit board on which electronic components are mounted, an insulating material is used. In recent years, with the development of communication systems and the like, further improvement of physical properties such as dielectric characteristics of insulating materials has been desired.
For example, patent document 1 discloses an insulating resin composition containing a silyl group-containing epoxy resin, a curing agent, and an inorganic filler such as silica for the purpose of reducing dielectric loss.
Prior art literature
Patent literature
Patent document 1: japanese patent application laid-open No. 2017-66360.
Disclosure of Invention
Problems to be solved by the invention
However, when an inorganic filler is added to a resin composition as in the method described in patent document 1, there is a problem that the adhesion strength to a metal foil or the mechanical strength of an insulating substrate is lowered.
In addition, in view of application to the next generation mobile communication system, there is a high possibility that the dielectric characteristics of the existing substrate material at high frequencies are insufficient.
Liquid crystal polyester films have been attracting attention as electronic substrate materials because of their excellent high-frequency characteristics and low water absorption.
The purpose of the present invention is to provide a liquid crystal polyester powder and a liquid crystal polyester composition, which can produce a liquid crystal polyester film having good quality as a film for electronic parts.
Further, an object of the present invention is to provide a method for producing a liquid crystal polyester film and a method for producing a laminate, which can produce a liquid crystal polyester film having good quality as a film for electronic parts.
Means for solving the problems
The present inventors have made intensive studies to solve the above problems, and as a result, they have found that a high-quality liquid crystal polyester film can be produced by containing a liquid crystal polyester powder having a predetermined average particle diameter and having a predetermined molecular weight, thereby completing the present invention.
That is, one embodiment of the present invention is the following liquid crystal polyester powder, liquid crystal polyester composition, film manufacturing method, and laminate manufacturing method.
< 1 > a liquid crystal polyester powder, wherein the liquid crystal polyester powder comprises a liquid crystal polyester having a number average molecular weight of 10000 or less, and the average particle diameter of the liquid crystal polyester powder is 0.5 to 20 μm.
The liquid crystal polyester powder of < 2 > the < 1 >, wherein the liquid crystal polyester powder has a relative dielectric constant of 3 or less at a frequency of 1GHz and a dielectric loss tangent of 0.005 or less at a frequency of 1 GHz.
< 3 > the liquid-crystalline polyester powder as described in < 1 > or < 2 >, wherein the liquid-crystalline polyester has a structural unit containing a naphthalene structure.
The liquid crystal polyester powder of < 4 > as described in < 3 >, wherein the content of the structural unit containing a naphthalene structure is 40 mol% or more with respect to 100 mol% of the total of all structural units in the liquid crystal polyester.
< 5 > the liquid crystal polyester powder as described in < 3 > or < 4 >, wherein the liquid crystal polyester has a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 Represents 2, 6-naphthalenediyl, 1, 4-phenylene or 4,4' -biphenylene.
Ar 2 And Ar is a group 3 Each independently represents 2, 6-naphthalenediyl, 2, 7-naphthalenediyl, 1, 4-phenylene, 1, 3-phenylene or 4,4' -biphenylene.
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently or not substituted by halogen atoms, alkyl groups having 1 to 10 carbon atoms or aryl groups having 6 to 20 carbon atomsAnd (3) substitution.
< 6 > a liquid crystalline polyester composition, wherein the liquid crystalline polyester composition contains a medium and the liquid crystalline polyester powder of any one of < 1 > - < 5 >.
< 7 > a method for producing a liquid crystal polyester film, wherein the method for producing a liquid crystal polyester film comprises: and a step of coating the liquid crystal polyester composition < 6 > on a support and performing a heat treatment to obtain a liquid crystal polyester film containing a liquid crystal polyester.
< 8 > a method for producing a laminate, wherein the method for producing a laminate comprises: and a step of applying the liquid crystal polyester composition < 6 > to a support and performing a heat treatment to form a liquid crystal polyester film containing a liquid crystal polyester, thereby obtaining a laminate comprising the support and the liquid crystal polyester film.
That is, the present invention includes the following aspects.
< 1 > a liquid crystal polyester powder, wherein the liquid crystal polyester powder comprises a liquid crystal polyester having a number average molecular weight of 10000 or less, and the average particle diameter of the liquid crystal polyester powder is 0.5 to 20 μm.
The liquid crystal polyester powder of < 2 > the < 1 >, wherein the liquid crystal polyester powder has a relative dielectric constant of 3 or less at a frequency of 1GHz and a dielectric loss tangent of 0.005 or less at a frequency of 1 GHz.
< 3 > the liquid-crystalline polyester powder as described in < 1 > or < 2 >, wherein the liquid-crystalline polyester has a structural unit containing a naphthalene structure.
The liquid crystal polyester powder of < 4 > as described in < 3 >, wherein the content of the structural unit containing a naphthalene structure is 40 mol% or more with respect to 100 mol% of the total of all structural units in the liquid crystal polyester.
< 5 > the liquid crystal polyester powder as described in < 3 > or < 4 >, wherein the liquid crystal polyester has a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 Represents 2, 6-naphthalenediyl, 1, 4-phenylene or 4,4' -biphenylene.
Ar 2 And Ar is a group 3 Each independently represents 2, 6-naphthalenediyl, 2, 7-naphthalenediyl, 1, 4-phenylene, 1, 3-phenylene or 4,4' -biphenylene.
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.
The liquid crystal polyester powder according to any one of < 6 > to < 1 > - < 5 >, wherein the liquid crystal polyester powder is insoluble in an aprotic solvent.
< 7 > a liquid crystal polyester composition, wherein the liquid crystal polyester composition contains a medium and the liquid crystal polyester powder of any one of < 1 > - < 6 >.
< 8 > the liquid crystalline polyester composition as described in < 7 >, wherein the medium is an aprotic solvent.
< 9 > a method for producing a liquid crystal polyester film, wherein the method for producing a liquid crystal polyester film comprises: and a step of coating the liquid crystal polyester composition < 7 > or < 8 > on a support and performing a heat treatment to obtain a liquid crystal polyester film containing a liquid crystal polyester.
< 10 > a method for producing a laminate, wherein the method for producing a laminate comprises: and a step of applying the liquid crystal polyester composition described as < 7 > or < 8 > to a support and performing a heat treatment to form a liquid crystal polyester film containing a liquid crystal polyester, thereby obtaining a laminate comprising the support and the liquid crystal polyester film.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, a liquid crystal polyester powder and a liquid crystal polyester composition capable of producing a liquid crystal polyester film having good quality as a film for electronic parts can be provided.
Further, according to the present invention, a method for producing a liquid crystal polyester film and a method for producing a laminate, which can produce a liquid crystal polyester film having good quality as a film for electronic parts, can be provided.
Drawings
Fig. 1 is a schematic view showing a process for producing a liquid crystal polyester film and a laminate according to an embodiment of the present invention.
Fig. 2 is a schematic diagram showing the structure of a membrane according to an embodiment of the present invention.
Fig. 3 is a schematic view showing the structure of a laminate according to an embodiment of the present invention.
Detailed Description
Hereinafter, embodiments of the liquid crystal polyester powder, the liquid crystal polyester composition, the method for producing a film, and the method for producing a laminate according to the present invention will be described.
Liquid crystalline polyester powder
The liquid crystal polyester powder of the embodiment comprises a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 [ mu ] m. The liquid crystal polyester powder of the embodiment is suitable as a raw material for the method for producing a liquid crystal polyester film or laminate of the embodiment. According to the liquid crystal polyester powder satisfying the above-mentioned regulation, a liquid crystal polyester film having good quality as a film for electronic parts can be produced. Examples of the quality standard include isotropy, thickness, and appearance (whether or not holes or through holes are formed) of the film. Details of the liquid crystal polyester film are described later.
The average particle diameter of the liquid crystal polyester powder is 20 μm or less, preferably 18 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less. When the average particle diameter of the liquid crystal polyester exceeds 20 μm, it is difficult to obtain a liquid crystal polyester film having good appearance. For example, as shown in examples described later, when the average particle diameter of the liquid crystal polyester exceeds 20 μm, there are cases where through holes are generated in the produced liquid crystal polyester film. The formation of the through-hole is likely to occur in a thickness range of 50 μm or less, which is a good film for electronic components. That is, by setting the average particle diameter of the liquid crystal polyester to 20 μm or less, a film having both good thickness and good appearance as a film for electronic parts can be easily produced.
In addition, from the viewpoint of ease of handling of the powder, the average particle diameter of the liquid crystal polyester powder is preferably 0.5 μm or more, more preferably 3 μm or more, and still more preferably 5 μm or more.
The upper limit and the lower limit of the average particle diameter value of the liquid crystal polyester powder can be freely combined. The average particle diameter of the liquid crystal polyester powder may be in the range of 0.5 μm or more and 20 μm or less, 3 μm or more and 18 μm or less, 5 μm or more and 15 μm or less, or 5 μm or more and 10 μm or less.
In the present specification, the "average particle diameter" means a particle diameter value of a point where the cumulative volume is 50% when the entire volume is 100% in a cumulative particle size distribution curve based on the volume measured by the laser diffraction scattering method (50% cumulative volume particle size D 50 )。
As a method of controlling the particle diameter within the above range, for example, in the case of using a jet mill, the control can be performed by changing the rotation speed of the classifying rotor, the pulverizing nozzle pressure, the processing speed, and the like.
In the method for producing a liquid crystal polyester film or laminate according to the embodiment described below, since it is not necessary to dissolve the liquid crystal polyester powder in a solvent, the liquid crystal polyester powder having excellent dielectric characteristics can be used as a raw material. From the liquid crystal polyester powder having excellent dielectric characteristics, a liquid crystal polyester film having excellent dielectric characteristics can be produced.
In the present specification, "dielectric characteristics" refers to characteristics related to relative permittivity and dielectric loss tangent.
The liquid crystal polyester powder of the embodiment has a relative dielectric constant of preferably 3 or less, preferably 2.9 or less, preferably 2.8 or less, more preferably less than 2.8, still more preferably 2.78 or less, and particularly preferably 2.76 or less at a frequency of 1 GHz. The relative dielectric constant of the liquid crystal polyester powder may be 2.5 or more, may be 2.6 or more, and may be 2.7 or more.
The upper limit value and the lower limit value of the relative dielectric constant of the liquid crystal polyester powder can be freely combined. As an example of the numerical range of the value of the relative dielectric constant of the liquid crystal polyester powder, it may be 2.5 or more and 3 or less, 2.6 or more and 2.78 or less, or 2.7 or more and 2.76 or less.
The dielectric loss tangent of the liquid crystal polyester powder of the embodiment at a frequency of 1GHz is preferably 0.005 or less, more preferably 0.004 or less, still more preferably 0.003 or less, still more preferably 0.0025 or less, and particularly preferably 0.002 or less. The dielectric loss tangent of the liquid crystal polyester powder may be 0.0003 or more, may be 0.0005 or more, and may be 0.001 or more.
The upper limit value and the lower limit value of the dielectric loss tangent of the liquid crystal polyester powder can be freely combined. As an example of the numerical range of the dielectric loss tangent of the liquid crystal polyester powder, it may be 0.0003 or more and 0.005 or less, 0.0005 or more and 0.004 or less, 0.001 or more and 0.003 or less, 0.001 or more and 0.0025 or less, and 0.001 or more and 0.002 or less.
The relative dielectric constant and dielectric loss tangent of the liquid crystal polyester powder at a frequency of 1GHz can be measured by a capacitance method using an impedance analyzer under the following conditions.
The liquid crystal polyester fine particle powder was melted at a temperature 5℃higher than the melting point measured by a flow tester and then cooled to solidify, to prepare a tablet having a diameter of 1cm and a thickness of 0.5 cm. The relative dielectric constant and dielectric loss tangent of the obtained tablets at 1GHz were measured under the following conditions.
The measuring method comprises the following steps: capacity method.
Electrode model: 16453A.
Measurement environment: 23 ℃, 50% rh.
Applying a voltage: 1V.
The relative dielectric constant and dielectric loss tangent of the liquid crystal polyester powder according to the embodiment may be different from those of a liquid crystal polyester film produced from the powder as a raw material. This is thought to be due to the difference in molecular weight of the liquid crystal polyester contained.
The liquid crystal polyester powder is preferably insoluble in a medium contained in a liquid crystal polyester composition described later, and more preferably insoluble in a protic solvent.
Here, whether or not the resin is insoluble in a medium can be confirmed by performing the following test. In the following test methods, the case where the medium is an aprotic solvent will be described.
Test method
The liquid crystal polyester powder (5 parts by weight) was stirred in an aprotic solvent (medium) (95 parts by weight) at 180℃for 6 hours under stirring at 200rpm using an anchor blade, and then cooled to room temperature. Then, after filtration using a membrane filter having a mesh size of 5 μm and a pressurized filter, residues on the membrane filter were confirmed. In this case, if no solid substance is confirmed, it is determined that the solid substance is soluble in the aprotic solvent (medium). When a solid material having a short diameter of 5 μm or more was confirmed, it was judged as insoluble in the aprotic solvent (medium). The solid material having a short diameter of 5 μm or more can be confirmed by microscopic observation.
The content of the liquid crystal polyester may be 50 to 100% by mass or 80 to 95% by mass based on 100% by mass of the liquid crystal polyester powder of the embodiment.
The number average molecular weight of the liquid crystal polyester in the liquid crystal polyester powder of the embodiment is 10000 or less, more preferably 3000 to 10000, still more preferably 4000 to 8000, particularly preferably 5000 to 7000. When the number average molecular weight of the liquid crystal polyester in the liquid crystal polyester powder exceeds 10000, the liquid crystal polyester composition becomes gel-like, and it becomes difficult to perform film processing excellent in isotropy. Further, since the thermal conductivity of the film in the thickness direction tends to be improved as the number average molecular weight of the liquid crystal polyester is smaller, it is preferable that the heat resistance and strength/rigidity of the film after heat treatment be good when the number average molecular weight of the liquid crystal polyester is equal to or higher than the lower limit value.
In the present specification, "number average molecular weight" is an absolute value measured using a gel permeation chromatograph-multi-angle light scattering photometer.
Hereinafter, details of the liquid crystal polyester contained in the liquid crystal polyester powder according to the embodiment will be described.
(liquid Crystal polyester)
The liquid crystal polyester is a liquid crystal polyester exhibiting liquid crystallinity in a molten state, and is preferably molten at a temperature of 450 ℃ or less. The liquid crystal polyester may be a liquid crystal polyester amide, a liquid crystal polyester ether, a liquid crystal polyester carbonate, or a liquid crystal polyester imide. The liquid crystal polyester is preferably a wholly aromatic liquid crystal polyester having only structural units derived from an aromatic compound as a raw material monomer.
In the present specification, "derived from" means that the chemical structure of the functional group contributing to polymerization is changed for polymerizing the raw material monomer, and no other structural change is caused.
Typical examples of the liquid crystal polyester are as follows.
1) A liquid crystal polyester obtained by polymerizing (polycondensing) an aromatic hydroxycarboxylic acid (i), an aromatic dicarboxylic acid (ii), and at least one compound selected from the group consisting of an aromatic diol, an aromatic hydroxylamine, and an aromatic diamine (iii).
2) A liquid crystal polyester obtained by polymerizing a plurality of aromatic hydroxycarboxylic acids.
3) A liquid crystal polyester obtained by polymerizing (i) an aromatic dicarboxylic acid and (ii) at least one compound selected from the group consisting of an aromatic diol, an aromatic hydroxylamine and an aromatic diamine.
4) A liquid crystal polyester obtained by polymerizing (i) a polyester such as polyethylene terephthalate and (ii) an aromatic hydroxycarboxylic acid.
Here, the aromatic hydroxycarboxylic acid, the aromatic dicarboxylic acid, the aromatic diol, the aromatic hydroxylamine, and the aromatic diamine may be used independently, and a polymerizable derivative thereof may be used in place of a part or all of them.
Examples of the polymerizable derivative of a compound having a carboxyl group such as an aromatic hydroxycarboxylic acid and an aromatic dicarboxylic acid include a substance (ester) which converts a carboxyl group into an alkoxycarbonyl group or an aryloxycarbonyl group, a substance (acyl halide) which converts a carboxyl group into a haloformyl group, and a substance (acid anhydride) which converts a carboxyl group into an acyloxycarbonyl group. Examples of polymerizable derivatives of compounds having a hydroxyl group such as an aromatic hydroxycarboxylic acid, an aromatic diol, and an aromatic hydroxylamine include those (acylates) obtained by acylating a hydroxyl group to convert it into an acyloxy group. Examples of polymerizable derivatives of compounds having an amino group such as aromatic hydroxylamine and aromatic diamine include substances (acylates) obtained by acylating an amino group to convert the amino group into an amido group.
The liquid crystal polyester preferably has a structural unit containing a 2-valent aromatic hydrocarbon group.
Examples of the liquid crystal polyester having a structural unit containing a 2-valent aromatic hydrocarbon group include: a liquid crystalline polyester having a structural unit represented by the following formula (1), a structural unit represented by the following formula (2) and a structural unit represented by the following formula (3), or a liquid crystalline polyester having a structural unit represented by the following formula (2) and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 、Ar 2 And Ar is a group 3 Each independently represents a 2-valent aromatic hydrocarbon group.
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.
In Ar 1 、Ar 2 And Ar is a group 3 Examples of the 2-valent aromatic hydrocarbon group include phenylene, naphthylene, and biphenylene.
Here, in Ar 1 、Ar 2 And Ar is a group 3 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a n-hexyl group, a 2-ethylhexyl group, a n-octyl group, a n-decyl group, and the like, and the number of carbon atoms thereof is usually 1 to 10. Examples of the aryl group include phenyl, o-tolyl, m-tolyl, p-tolyl, and p-tolyl Tolyl group, 1-naphthyl group, 2-naphthyl group and the like, and the number of carbon atoms thereof is usually 6 to 20. In the case where the hydrogen atom is substituted with these groups, each of them is substituted with Ar 1 、Ar 2 Or Ar 3 The number of the groups is usually 2 or less, preferably 1 or less, independently of each other.
The liquid crystalline polyester more preferably has a structural unit containing a naphthalene structure.
Examples of the liquid crystal polyester having a structural unit containing a 2-valent naphthalene structure include a liquid crystal polyester having a structural unit represented by the following formula (1), a structural unit represented by the following formula (2) and a structural unit represented by the following formula (3), and a liquid crystal polyester having a structural unit represented by the following formula (2) and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
[Ar 1 、Ar 2 And Ar is a group 3 Each independently represents a 2-valent aromatic hydrocarbon group (however, a plurality of Ar 1 、Ar 2 And Ar is a group 3 At least one of which is naphthylene).
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.]
The Ar is as follows 1 、Ar 2 And Ar is a group 3 Can each independently represent a naphthylene group or a phenylene group (however, a plurality of Ar 1 、Ar 2 And Ar is a group 3 At least one of which is naphthylene).
The liquid crystal polyester has a structural unit represented by the above formula (1), a structural unit represented by the above formula (2) and a structural unit represented by the above formula (3), and a plurality of Ar 1 、Ar 2 And Ar is a group 3 In the case where at least one of them is naphthylene, a plurality of Ar are preferable 1 And/or Ar 2 At least one of which is naphthylene.
The liquid crystalline polyester has a structural unit represented by the above formula (2) and is represented by the above formulaA structural unit represented by the formula (3) and a plurality of Ar 2 And Ar is a group 3 In the case where at least one of them is naphthylene, a plurality of Ar are preferable 2 At least one of which is naphthylene.
The Ar is as follows 1 、Ar 2 And Ar is a group 3 The naphthylene group in (a) is preferably a 2, 6-naphthalenediyl group or a 2, 7-naphthalenediyl group, and more preferably a 2, 6-naphthalenediyl group.
The content of the structural units containing a naphthalene structure in the liquid crystal polyester is preferably 40 mol% or more, more preferably 50 mol% or more, and still more preferably 60 mol% or more, based on 100 mol% of the total amount of all the structural units in the liquid crystal polyester (the mass of each structural unit constituting the liquid crystal polyester is divided by the formula weight of each structural unit to obtain the material equivalent (mol) of each structural unit, and the total of these values is calculated). By setting the content of the structural unit containing a naphthalene structure to the above lower limit or more, the relative dielectric constant of the liquid crystal polyester can be further reduced.
The content of the structural unit containing a naphthalene structure in the liquid crystal polyester is preferably 90 mol% or less, more preferably 80 mol% or less, based on 100 mol% of the total amount of all the structural units in the liquid crystal polyester. By setting the content of the structural unit containing a naphthalene structure to the above upper limit or less, the reaction stability in producing the liquid crystal polyester can be ensured.
As an example of the numerical range of the content of the structural unit containing a naphthalene structure, 40 mol% or more and 90 mol% or less, 50 mol% or more and 80 mol% or less, and 60 mol% or more and 80 mol% or less may be used.
The liquid crystal polyester may include the structural unit represented by the above formula (2) and the structural unit represented by the above formula (3) among the structural units represented by the above formulas (1) to (3), and may be a liquid crystal polyester having all kinds of the structural units represented by the above formulas (1) to (3).
The liquid crystal polyester may be a liquid crystal polyester composed of the structural units represented by the above formulas (1) to (3) and the structural unit represented by the above formula (3), or may be a liquid crystal polyester composed of all kinds of structural units represented by the above formulas (1) to (3).
Examples of the liquid crystal polyester having the structural units represented by the above formulas (1) to (3) include a liquid crystal polyester having the structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 、Ar 2 And Ar is a group 3 Each independently represents a naphthalenediyl group, a phenylene group or a biphenylene group.
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.
The liquid crystal polyester includes the following liquid crystal polyesters.
A liquid crystal polyester having a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 Represents 2, 6-naphthalenediyl, 1, 4-phenylene or 4,4' -biphenylene.
Ar 2 And Ar is a group 3 Each independently represents 2, 6-naphthalenediyl, 2, 7-naphthalenediyl, 1, 4-phenylene, 1, 3-phenylene or 4,4' -biphenylene.
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.
Examples of the liquid crystal polyester having the structural units represented by the above formulas (1) to (3) include a liquid crystal polyester having the structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3).
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 Represents naphthalenediyl, ar 2 Represents naphthalenediyl or phenylene, ar 3 Represents a phenylene group.
From Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.
When the liquid crystal polyester has all kinds of structural units represented by the above formulas (1) to (3), the preferable content ratio of each structural unit in the liquid crystal polyester can be listed as follows.
The content of the structural unit (1) in the liquid crystal polyester is preferably 30 mol% or more and 80 mol% or less, more preferably 40 mol% or more and 70 mol% or less, and still more preferably 45 mol% or more and 65 mol% or less, based on 100 mol% of the total amount of all the structural units in the liquid crystal polyester.
The content of the structural unit (2) in the liquid crystal polyester is preferably 10 mol% or more and 35 mol% or less, more preferably 15 mol% or more and 30 mol% or less, and still more preferably 17.5 mol% or more and 27.5 mol% or less, based on 100 mol% of the total of all the structural units in the liquid crystal polyester.
The content of the structural unit (3) in the liquid crystal polyester is preferably 10 mol% or more and 35 mol% or less, more preferably 15 mol% or more and 30 mol% or less, and still more preferably 17.5 mol% or more and 27.5 mol% or less, based on 100 mol% of the total of all the structural units in the liquid crystal polyester.
The content of the structural unit (2) and the content of the structural unit (3) in the liquid crystal polyester are preferably equal to each other, and when the content is different, the difference between the content of the structural unit (2) and the content of the structural unit (3) is preferably 5 mol% or less.
In the case of liquid crystalline polyesters having high heat resistance or high melt tensionAr of structural unit (1) 1 The content ratio of the 2, 6-naphthalenediyl group (for example, a structural unit derived from 2-hydroxy-6-naphthoic acid) is preferably 40 mol% or more and 74.8 mol% or less, more preferably 40 mol% or more and 64.5 mol% or less, and still more preferably 50 mol% or more and 58 mol% or less, based on the total amount of all structural units in the liquid crystal polyester.
Ar of structural unit (2) in liquid crystalline polyester 2 The content ratio of the 2, 6-naphthalenediyl group (for example, a structural unit derived from 2, 6-naphthalenedicarboxylic acid) is preferably 10.0 mol% or more and 35 mol% or less, more preferably 12.5 mol% or more and 30 mol% or less, still more preferably 15 mol% or more and 25 mol% or less, based on the total amount of all structural units in the liquid crystal polyester.
In addition, in the liquid crystal polyester, ar of the structural unit (2) 2 The content ratio of the 1, 4-phenylene group (for example, structural units derived from terephthalic acid) is preferably 0.2 mol% or more and 15 mol% or less, more preferably 0.5 mol% or more and 12 mol% or less, and still more preferably 2 mol% or more and 10 mol% or less, based on the total amount of all structural units in the liquid crystal polyester.
Ar of structural unit (3) in liquid crystalline polyester 3 The content ratio of the 1, 4-phenylene group (for example, a structural unit derived from hydroquinone) is preferably 12.5 mol% or more and 30 mol% or less, more preferably 17.5 mol% or more and 30 mol% or less, still more preferably 20 mol% or more and 25 mol% or less, with respect to the total amount of all the structural units in the liquid crystal polyester.
In the liquid-crystalline polyester, ar in the structural unit (2) 2 Is 2, 6-naphthalenediyl content relative to Ar 2 Is 2, 6-naphthalenediyl and Ar 2 The total amount of 1, 4-phenylene groups, for example, the content of the structural unit derived from 2, 6-naphthalene dicarboxylic acid is preferably 0.5 mol times or more, more preferably 0.6 mol times or more, relative to the total amount of the structural unit derived from 2, 6-naphthalene dicarboxylic acid and the structural unit derived from terephthalic acid.
The proportion of each structural unit to be blended may be 100 mol% based on the total amount of all structural units derived from the aromatic compound in the liquid crystal polyester, based on the total amount of 100 mol% of all structural units in the liquid crystal polyester.
The sum of the above-mentioned constituent units of the liquid-crystalline polyester is not more than 100 mol%.
The liquid crystal polyester of the embodiment can be produced, for example, by melt-polycondensing each monomer to which a structural unit is added.
In this case, for rapidly performing melt polycondensation, an ester-forming derivative thereof is preferably used as each of the above monomers.
Examples of the ester-forming derivative include compounds having a carboxyl group such as an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid, such as a substance having a carboxyl group converted into a haloformyl group, a substance having a carboxyl group converted into an acyloxycarbonyl group, and a substance having a carboxyl group converted into an alkoxycarbonyl group or an aryloxycarbonyl group.
In addition, in the case of a compound having a hydroxyl group such as an aromatic hydroxycarboxylic acid or an aromatic diol, a substance in which a hydroxyl group is converted into an acyloxy group can be mentioned. Among them, a substance having a hydroxyl group converted into an acyloxy group, that is, an aromatic acyloxycarboxylic acid having an acylated hydroxyl group is preferably used as an ester-forming derivative of an aromatic hydroxycarboxylic acid, and an aromatic diacyloxy compound having an acylated hydroxyl group is preferably used as an ester-forming derivative of an aromatic diol. The acylation is preferably carried out by acetylation with acetic anhydride, and the ester-forming derivative produced by the acetylation can be polycondensed with deacetylation.
The melt polymerization may be carried out in the presence of a catalyst, and examples of the catalyst include metal compounds such as magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate and antimony trioxide, and nitrogen-containing heterocyclic compounds such as 4- (dimethylamino) pyridine and 1-methylimidazole, and nitrogen-containing heterocyclic compounds are preferably used. The melt polymerization may be further subjected to solid-phase polymerization, if necessary.
The liquid crystal polyester in the liquid crystal polyester powder of the embodiment has a flow initiation temperature of preferably 250 ℃ or higher, more preferably 250 ℃ or higher and 350 ℃ or lower, and still more preferably 260 ℃ or higher and 330 ℃ or lower. The higher the flow initiation temperature of the liquid crystal polyester, the more easily the heat resistance, strength and rigidity are improved, but when too high, the pulverizing property becomes poor and it is difficult to obtain a powder of a target particle diameter.
The flow onset temperature, also known as the viscous flow temperature or flow temperature, is measured using a capillary rheometer at 9.8MPa (100 kg/cm 2 ) The temperature at which the liquid crystal polyester was melted while the temperature was increased at a rate of 4 ℃/min and the liquid crystal polyester was extruded from a nozzle having an inner diameter of 1mm and a length of 10mm showed a viscosity of 4800pa·s (48000 poise) was a standard for the molecular weight of the liquid crystal polyester (see xiaozhen, liquid crystal polymer-synthesis/molding/application- (liquid crystal polyethylene-synthesis/molding/application-)), CMC (corporation, 6/5/1987, p.95).
For example, the liquid crystal polyester powder of the embodiment can be obtained by pulverizing a powder of a liquid crystal polyester having a number average molecular weight of 10000 or less produced by the above-mentioned production method of a liquid crystal polyester, if necessary, using a jet mill or the like to have an average particle diameter of 0.5 to 20 μm.
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder comprising a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding a liquid crystal polyester powder having a volume average particle diameter of 9 μm which is composed of a structural unit derived from 2-hydroxy-6-naphthoic acid, a structural unit derived from 2, 6-naphthalene dicarboxylic acid, a structural unit derived from terephthalic acid and a structural unit derived from hydroquinone).
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder comprising a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding a liquid crystal polyester powder having a volume average particle diameter of 9 μm which is a polymer obtained by reacting a mixture of 2-hydroxy-6-naphthoic acid (5.5 mol), 2, 6-naphthalenedicarboxylic acid (1.75 mol), terephthalic acid (0.5 mol), hydroquinone (2.475 mol), acetic anhydride (12 mol) and 1-methylimidazole as a catalyst).
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder containing a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding a liquid crystal polyester powder having a volume average particle diameter of 9 μm obtained by pulverizing a liquid crystal polyester having a flow initiation temperature of 265℃which is composed of a structural unit derived from 2-hydroxy-6-naphthoic acid, a structural unit derived from 2, 6-naphthalene dicarboxylic acid, a structural unit derived from terephthalic acid, and a structural unit derived from hydroquinone).
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder comprising a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding liquid crystal polyester powders comprising a structural unit derived from 2-hydroxy-6-naphthoic acid, a structural unit derived from 2, 6-naphthalene dicarboxylic acid, a structural unit derived from terephthalic acid and a structural unit derived from hydroquinone and having a volume average particle diameter of 9 μm).
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder containing a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding a liquid crystal polyester powder having a volume average particle diameter of 9 μm obtained by reacting a mixture of 2-hydroxy-6-naphthoic acid (5.5 mol), 2, 6-naphthalenedicarboxylic acid (1.75 mol), terephthalic acid (0.5 mol), hydroquinone (2.475 mol), acetic anhydride (12 mol) and 1-methylimidazole as a catalyst).
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder containing a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding a liquid crystal polyester powder having a volume average particle diameter of 9 μm obtained by pulverizing a liquid crystal polyester having a flow initiation temperature of 265 ℃ and containing a structural unit derived from 2-hydroxy-6-naphthoic acid, a structural unit derived from 2, 6-naphthalene dicarboxylic acid, a structural unit derived from terephthalic acid, and a structural unit derived from hydroquinone).
The liquid crystal polyester powder of the embodiment may be a liquid crystal polyester powder containing a liquid crystal polyester having a number average molecular weight of 10000 or less and an average particle diameter of 0.5 to 20 μm (excluding a liquid crystal polyester powder having a volume average particle diameter of 9 μm obtained by pulverizing a polymer having a flow initiation temperature of 265℃obtained by reacting a mixture of 2-hydroxy-6-naphthoic acid (5.5 mol), 2, 6-naphthalenedicarboxylic acid (1.75 mol), terephthalic acid (0.5 mol), hydroquinone (2.475 mol), acetic anhydride (12 mol) and 1-methylimidazole as a catalyst).
The "volume average particle diameter" herein means a value obtained by measuring a dispersion of a liquid crystalline polyester powder obtained by dispersing 0.01g of the liquid crystalline polyester powder in about 10g of pure water by ultrasonic waves for 5 minutes using a scattering particle diameter distribution measuring apparatus (for example, "LA-950V2" of HORIBA, ltd.). The "volume average particle diameter" means a particle diameter value of a point where the cumulative volume is 50% when the whole is 100% in the cumulative particle size distribution curve based on the volume measured by the scattering particle size distribution measuring apparatus (50% cumulative volume particle size D) 50 )。
In addition, although acetic acid derived from acetic anhydride as a raw material of the liquid crystal polyester may remain in the liquid crystal polyester powder of the embodiment, the upper limit value of the amount of residual acetic acid which can be contained in 100 mass% of the liquid crystal polyester powder of the embodiment is preferably 1 mass% or less, more preferably 500 mass ppm or less, and still more preferably 300 mass ppm or less from the viewpoint of mechanical properties after film formation. The lower limit value of the residual acetic acid content in 100 mass% of the liquid crystal polyester powder according to the embodiment is preferably 30 mass ppm or more, more preferably 50 mass ppm or more, and still more preferably 100 mass ppm or more from the viewpoint of the grindability.
The upper limit value and the lower limit value of the residual acetic acid amount which can be contained in 100 mass% of the liquid crystal polyester powder can be freely combined. As an example of the numerical range of the amount of residual acetic acid that can be contained in 100 mass% of the liquid crystal polyester powder, it may be 30 mass ppm or more and 1 mass% or less, 50 mass ppm or more and 500 mass ppm or less, or 100 mass ppm or more and 300 mass ppm or less.
According to the liquid crystal polyester powder of the embodiment, a liquid crystal polyester film having good quality as a film for electronic parts can be produced. Examples of the quality standard include isotropy, thickness, and appearance (whether or not holes or through holes are formed) of the film.
When the number average molecular weight of the liquid crystal polyester in the liquid crystal polyester powder of the embodiment is a relatively small value of 10000 or less, the liquid crystal polyester composition becomes suitable for coating, and the molten state of the liquid crystal polyester film at the time of heat treatment becomes good, so that film formation processing capable of producing a liquid crystal polyester film excellent in isotropy becomes possible. Further, since the average particle diameter of the liquid crystal polyester powder of the embodiment is 0.5 to 20 μm, the liquid crystal polyester powder has a suitable thinness for use as a film for electronic parts, and a high-quality polyester film with suppressed occurrence of holes or through holes can be obtained.
According to the liquid crystal polyester powder of the embodiment, a liquid crystal polyester film excellent in isotropy can be produced.
Conventionally, a liquid crystal polyester film is generally produced by a melt molding method or a casting method in which a liquid crystal polyester is melted.
The melt molding method is a method of molding a film by extruding a kneaded product from an extruder. However, in the film produced by the melt molding method, the liquid crystal polyester molecules are oriented more in the film-forming direction (also referred to as extrusion direction, machine Direction (MD)) than in the transverse direction to the extrusion direction (direction perpendicular to the extrusion direction and the thickness direction of the film, transverse Direction (TD)), and thus it is difficult to obtain a liquid crystal polyester excellent in isotropy.
In contrast, according to the liquid crystal polyester powder of the embodiment, a liquid crystal polyester film having excellent isotropy can be produced. The liquid crystal polyester powder of the embodiment is suitable as a raw material for the method for producing a liquid crystal polyester film of the embodiment, and by applying the method, a liquid crystal polyester film excellent in isotropy can be easily produced without requiring an operation of molding by extrusion as described above.
The term "excellent isotropy" of the liquid crystal polyester film means that the molecular orientation degree (MOR) of the liquid crystal polyester film is in the range of 1 to 1.1.
According to the liquid crystal polyester powder of the embodiment, a liquid crystal polyester film having both dielectric characteristics and isotropy can be produced.
The orientation of the liquid crystal polyester film manufactured by the solution casting method is more isotropic than that of the liquid crystal polyester film formed by the melt molding method. However, there is a limit that a liquid crystal polyester having a property of being soluble in a solvent must be used in order to apply the solution casting method. In a liquid crystal polyester having improved solubility in a solvent, for example, the dielectric characteristics may be lowered by increasing the polarity.
As described above, it is difficult to make both the dielectric characteristics and isotropy of the liquid crystal polyester film at a high level.
In contrast, according to the liquid crystal polyester powder of the embodiment, a liquid crystal polyester film having both dielectric characteristics and isotropy can be produced. The liquid crystal polyester powder of the embodiment is suitable as a raw material for the method for producing a liquid crystal polyester film of the embodiment, and by applying the method, a liquid crystal polyester film excellent in isotropy can be easily produced without requiring an operation of dissolving the liquid crystal polyester powder in a solvent. In addition, since a liquid crystal polyester excellent in dielectric characteristics can be used as a raw material, a liquid crystal polyester film excellent in dielectric characteristics and isotropy can be easily produced.
Liquid crystalline polyester composition
The liquid crystal polyester composition of the embodiment contains a medium and the liquid crystal polyester powder of the embodiment. The liquid crystal polyester composition is suitable for use in the production of a liquid crystal polyester film described later.
The liquid crystal polyester composition of the embodiment preferably contains an aprotic solvent and a liquid crystal polyester powder insoluble in the aprotic solvent.
The liquid crystal polyester powder may be exemplified by the examples described in the above "liquid crystal polyester powder", and therefore, the description thereof is omitted.
The medium is not particularly limited as long as the liquid crystal polyester powder is not dissolved, and is preferably a dispersion medium. In addition, the medium is preferably a fluid, more preferably a liquid.
The term "dispersed" as used herein is a term for distinguishing from a state in which the liquid crystal polyester powder is dissolved (except for a state in which the liquid crystal polyester powder is dissolved in the liquid crystal polyester composition). The liquid crystalline polyester powder may be distributed in the composition in such a way that there may be non-uniform portions. The liquid crystal polyester powder in the composition may be in a state in which the liquid crystal polyester composition can be applied to a support in a method for producing a liquid crystal polyester film described later.
Examples of the medium include halogenated hydrocarbons such as methylene chloride, chloroform, 1-dichloroethane, 1, 2-dichloroethane, 1, 2-tetrachloroethane, 1-chlorobutane, chlorobenzene, and o-dichlorobenzene; halogenated phenols such as p-chlorophenol, pentachlorophenol and pentafluorophenol; ethers such as diethyl ether, tetrahydrofuran, and 1, 4-dioxane; ketones such as acetone and cyclohexanone; esters such as ethyl acetate and γ -butyrolactone; carbonates such as ethylene carbonate and propylene carbonate; amines such as triethylamine; nitrogen-containing heterocyclic aromatic compounds such as pyridine; nitriles such as acetonitrile and succinonitrile; amides such as N, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone; urea compounds such as tetramethylurea; nitro compounds such as nitromethane and nitrobenzene; sulfur compounds such as dimethyl sulfoxide and sulfolane; and phosphorus compounds such as hexamethylphosphoric acid amide and tri-n-butyl phosphoric acid, and two or more of them may be used.
The medium is preferably a medium containing an aprotic compound, particularly an aprotic compound having no halogen atom, as a main component, from the viewpoint of low corrosiveness and easiness in handling, and the proportion of the aprotic compound to the entire medium is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and even more preferably 90 to 100% by mass. In addition, as the aprotic compound, an amide such as N, N-dimethylformamide, N-dimethylacetamide, tetramethylurea, N-methylpyrrolidone, or an ester such as γ -butyrolactone is preferably used, and N, N-dimethylformamide, N-dimethylacetamide, and N-methylpyrrolidone are more preferably used.
In addition, as the medium, a medium containing a compound having a boiling point of 220 ℃ or less at 1 atmosphere as a main component is preferable from the viewpoint of easy removal, and the proportion of the compound having a boiling point of 220 ℃ or less at 1 atmosphere to the whole medium is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, still more preferably 90 to 100% by mass, and as the aprotic compound, a compound having a boiling point of 220 ℃ or less at 1 atmosphere is preferably used.
The proportion of the liquid crystal polyester powder may be 50 to 100% by mass, 70 to 100% by mass, or 90 to 100% by mass, based on the total amount of the solid components contained in the liquid crystal polyester composition.
The proportion of the liquid crystal polyester powder contained in the liquid crystal polyester composition is preferably 0.1 to 60% by mass, more preferably 1 to 50% by mass, still more preferably 3 to 40% by mass, and particularly preferably 5 to 30% by mass, relative to the total amount of the liquid crystal polyester powder and the medium.
The liquid crystal polyester composition can be obtained by mixing the medium, the liquid crystal polyester powder and other components used as needed together or in an appropriate order.
The liquid crystal polyester composition may contain one or more of a filler, an additive, a resin other than the liquid crystal polyester, and the like.
Examples of the filler include inorganic fillers such as silica, alumina, titanium oxide, barium titanate, strontium titanate, aluminum hydroxide, and calcium carbonate; and an organic filler such as a cured epoxy resin, a crosslinked benzoguanamine resin, or a crosslinked acrylic resin, the content of which may be 0 parts by mass or less, preferably 100 parts by mass or less, per 100 parts by mass of the liquid crystal polyester.
Examples of the additives include leveling agents, antifoaming agents, antioxidants, ultraviolet absorbers, flame retardants, and colorants, and the content thereof may be 0 parts by mass or less, preferably 5 parts by mass or less, relative to 100 parts by mass of the liquid crystal polyester.
Examples of the resin other than the liquid crystal polyester include thermoplastic resins other than the liquid crystal polyester, such as polypropylene, polyamide, polyester other than the liquid crystal polyester, polyphenylene sulfide, polyether ketone, polycarbonate, polyether sulfone, polyphenylene oxide and its modified product, and polyether imide; an elastomer such as a copolymer of glycidyl methacrylate and polyethylene; and thermosetting resins such as phenolic resins, epoxy resins, polyimide resins, and cyanate resins, the content of which may be 0 parts by mass or less, preferably 20 parts by mass or less, relative to 100 parts by mass of the liquid crystal polyester.
The liquid crystal polyester composition of the embodiment may contain more than 70 mass% and 100 mass% or less of the liquid crystal polyester of the above embodiment, and may contain 80 to 100 mass% of the liquid crystal polyester of the above embodiment, based on 100 mass% of the total liquid crystal polyester contained. The liquid crystal polyester may be a liquid crystal polyester not corresponding to the following component (X), for example, a liquid crystal polyester of the above 1) to 4), a liquid crystal polyester having a structural unit represented by the above formula (1), a structural unit represented by the above formula (2) and a structural unit represented by the above formula (3), or a liquid crystal polyester having a structural unit represented by the above formula (2) and a structural unit represented by the above formula (3), among the liquid crystal polyesters exemplified in the paragraphs of the embodiment (liquid crystal polyester).
The liquid crystal polyester composition of the embodiment may be a liquid crystal polyester composition containing a medium and a liquid crystal polyester powder (however, the content of the liquid crystal polyester soluble in an aprotic solvent is less than 5 mass% with respect to 100 mass% of the total of the liquid crystal polyesters).
The liquid crystal polyester composition of the embodiment may be a liquid crystal polyester composition containing a medium and a liquid crystal polyester powder (except for the liquid crystal polyester soluble in an aprotic solvent in the case where the liquid crystal polyester powder is contained as a resin powder).
As the aprotic solvent-soluble liquid crystalline polyester, a liquid crystalline polyester containing a structural unit derived from 4-hydroxyacetanilide may be mentioned.
As the aprotic solvent-soluble liquid crystalline polyester, a liquid crystalline polyester composed of a structural unit derived from 6-hydroxy-2-naphthoic acid, a structural unit derived from 4-hydroxyacetanilide and a structural unit derived from isophthalic acid may be mentioned.
The liquid crystal polyester soluble in an aprotic solvent may be a liquid crystal polyester which is a polymer obtained by reacting a mixture of 6-hydroxy-2-naphthoic acid (5.0 mol), 4-hydroxyacetanilide (2.5 mol), isophthalic acid (2.5 mol) and acetic anhydride (8.4 mol).
Hereinafter, a liquid crystal polyester soluble in an aprotic solvent will be described.
Component (X)
The component (X) is a liquid crystalline polyester soluble in an aprotic solvent. Here, the "soluble in aprotic solvents" can be confirmed by performing the following test.
Test method
The liquid crystalline polyester is stirred in an aprotic solvent at 120 to 180 ℃ for 1 to 6 hours and then cooled to room temperature (23 ℃). Then, after filtration using a 5 μm membrane filter and a pressurized filter, residues on the membrane filter were confirmed. In this case, if the solid matter is not confirmed, it is determined that the solid matter is soluble in the aprotic solvent.
More specifically, 1 part by mass of a liquid crystalline polyester was stirred in 99 parts by mass of an aprotic solvent at 140℃for 4 hours, and then cooled to 23 ℃. Then, after filtration using a 5 μm membrane filter and a pressurized filter, residues on the membrane filter were confirmed. In this case, if the solid matter is not confirmed, it is determined that the solid matter is soluble in the aprotic solvent.
The liquid crystalline polyester (X) preferably contains, as a structural unit, structural units represented by the following formulas (X1), (X2) and (X3).
In one aspect, the content of the structural unit represented by the formula (X1) is 30 to 80 mol%, the content of the structural unit represented by the formula (X2) is 35 to 10 mol%, and the content of the structural unit represented by the formula (X3) is 35 to 10 mol%, based on the total content of all the structural units constituting the component (X).
However, the total content of the structural unit represented by the formula (X1), the structural unit represented by the formula (X2), and the structural unit represented by the formula (X3) is not more than 100 mol%.
(X1)-O-Ar1-CO-
(X2)-CO-Ar2-CO-
(X3)-X-Ar3-Y-
( In X1 to X3, ar1 represents a 1, 4-phenylene group, a 2, 6-naphthalenediyl group or a 4,4' -biphenylene group. Ar2 represents 1, 4-phenylene, 1, 3-phenylene or 2, 6-naphthalenediyl. Ar3 represents 1, 4-phenylene or 1, 3-phenylene. X represents-NH-, Y represents-O-or NH-. )
The structural unit (X1) is a structural unit derived from an aromatic hydroxycarboxylic acid, the structural unit (X2) is a structural unit derived from an aromatic dicarboxylic acid, and the structural unit (X3) is a structural unit derived from an aromatic diamine or an aromatic amine having a phenolic hydroxyl group. The component (X) may use an ester-or amide-forming derivative of the above-mentioned constituent unit instead of the above-mentioned constituent unit.
In this embodiment, it is preferable that Ar1 is 2, 6-naphthalenediyl, ar2 is 1, 3-phenylene, ar3 is 1, 4-phenylene, and Y is-O-.
Examples of the ester-forming derivative of carboxylic acid include a substance in which a carboxyl group is changed to a derivative having high reactivity such as an acid chloride or an acid anhydride which promotes the reaction of forming a polyester, and a substance in which a carboxyl group is formed into an ester with an alcohol or ethylene glycol to form a polyester by transesterification.
Examples of the ester-forming derivative of a phenolic hydroxyl group include those in which a phenolic hydroxyl group forms an ester with a carboxylic acid.
Examples of the amide-forming derivative of an amino group include amide-forming derivatives of an amino group and carboxylic acids.
The repeating structural unit of the component (X) used in the present embodiment may be the following, but is not limited thereto.
The structural unit represented by the formula (X1) may be, for example, a structural unit derived from p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid or 4' -hydroxy-4-biphenylcarboxylic acid, or two or more of the structural units may be contained in the whole structural units. Among these structural units, the (X) component comprising a structural unit derived from 6-hydroxy-2-naphthoic acid is preferably used.
The content of the structural unit (X1) is 30 mol% or more and 80 mol% or less, preferably 40 mol% or more and 70 mol% or less, and more preferably 45 mol% or more and 65 mol% or less, with respect to the total structural units constituting the component (X).
When the structural unit (X1) is more, the solubility in a solvent tends to be significantly reduced, and when it is too less, the liquid crystallinity tends not to be exhibited. That is, when the content of the structural unit (X1) is within the above range, the solubility in a solvent is good, and the liquid crystallinity is easily exhibited.
Examples of the structural unit represented by the formula (X2) include structural units derived from terephthalic acid, isophthalic acid, and 2, 6-naphthalene dicarboxylic acid, and two or more of the structural units may be contained in the entire structural units. Among these structural units, from the viewpoint of solubility in a solvent, a liquid crystalline polyester containing structural units derived from isophthalic acid is preferably used.
The content of the structural unit (X2) is preferably 10 mol% or more and 35 mol% or less, more preferably 15 mol% or more and 30 mol% or less, and particularly preferably 17.5 mol% or more and 27.5 mol% or less, with respect to the content of the entire structural units constituting the component (X). When the structural unit (X2) is too large, the liquid crystal property tends to be lowered, and when it is small, the solubility in a solvent tends to be lowered. That is, when the content of the structural unit (X2) is within the above range, the liquid crystal property is good, and the solubility in a solvent is also good.
The structural unit represented by the formula (X3) may be, for example, a structural unit derived from 3-aminophenol, 4-aminophenol, 1, 4-phenylenediamine or 1, 3-phenylenediamine, or two or more of the structural units may be contained in the whole structural units.
Among these structural units, from the viewpoint of reactivity, a liquid crystalline polyester containing structural units derived from 4-aminophenol is preferably used.
The content of the structural unit (X3) is preferably 10 mol% or more and 35 mol% or less, more preferably 15 mol% or more and 30 mol% or less, and particularly preferably 17.5 mol% or more and 27.5 mol% or less, with respect to the content of the entire structural units constituting the component (X). When the structural unit (3) is too much, the liquid crystal property tends to be lowered, and when it is too little, the solubility in a solvent tends to be lowered. That is, when the content of the structural unit (X3) is within the above range, the liquid crystal property is good, and the solubility in a solvent is also good.
The structural unit (X3) is preferably used in substantially the same amount as the structural unit (X2), and the polymerization degree of the liquid crystalline polyester can be controlled by setting the content of the structural unit (X3) to-10 to +10 mol% relative to the content of the structural unit (X2).
The method for producing the component (X) of the present embodiment is not particularly limited, and examples thereof include a method in which an acylate obtained by acylating an aromatic hydroxy acid corresponding to the structural unit (X1), an aromatic amine having a phenolic hydroxyl group corresponding to the structural unit (X3), or a phenolic hydroxyl group or an amino group of an aromatic diamine with an excess of a fatty acid anhydride is subjected to transesterification (polycondensation) and melt polymerization; the aromatic dicarboxylic acid is an aromatic dicarboxylic acid corresponding to the structural unit (X2) (see JP-A2002-220444 and JP-A2002-146003).
In the acylation reaction, the amount of the fatty acid anhydride to be added is preferably 1.0 to 1.2 equivalents, more preferably 1.05 to 1.1 equivalents, relative to the total amount of the phenolic hydroxyl group and the amino group. When the amount of the fatty acid anhydride to be added is too small, the acylate, the raw material monomer, and the like tend to sublimate during transesterification/amide exchange (polycondensation), and the reaction system tends to be easily blocked, and when it is too large, the coloration of the obtained liquid crystalline polyester tends to be remarkable. That is, when the amount of the fatty acid anhydride added is within the above range, the reaction of the acylate, the raw material monomer, or the like is good at the time of transesterification/amide exchange (polycondensation), and the obtained liquid crystalline polyester is not excessively colored.
The acylation reaction is preferably carried out at 130 to 180℃for 5 minutes to 10 hours, more preferably 140 to 160℃for 10 minutes to 3 hours.
The fatty acid anhydride used in the acylation reaction is not particularly limited, and examples thereof include acetic anhydride, propionic anhydride, tyric anhydride, iso-tyric anhydride, valeric anhydride, pivalic anhydride, 2-ethylhexanoic anhydride, monochloroacetic anhydride, dichloroacetic anhydride, trichloroacetic anhydride, monobromoacetic anhydride, dibromoacetic anhydride, tribromoacetic anhydride, monofluoroacetic anhydride, difluoroacetic anhydride, trifluoroacetic anhydride, glutaric anhydride, maleic anhydride, succinic anhydride, and β -bromopropionic anhydride, and two or more of these may be used in combination. In this embodiment, acetic anhydride, propionic anhydride, butyric anhydride or isobutyric anhydride is preferable, and acetic anhydride is more preferable.
In the transesterification/transamidation (polycondensation), the acyl group of the acylate is preferably 0.8 to 1.2 times equivalent to the carboxyl group.
The transesterification/transamidation (polycondensation) is preferably performed while the temperature is raised to 400℃at a rate of 0.1 to 50℃per minute, more preferably, while the temperature is raised to 350℃at a rate of 0.3 to 5℃per minute.
In the case of transesterification/transamidation (polycondensation) of the acylate with the carboxylic acid, the fatty acid and unreacted fatty anhydride as by-products are preferably distilled off to the outside of the system by evaporation or the like.
The acylation reaction and transesterification/transamidation (polycondensation) may be performed in the presence of a catalyst. As the catalyst, a catalyst conventionally known 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 N, N-dimethylaminopyridine and N-methylimidazole.
Among these catalysts, heterocyclic compounds containing at least two nitrogen atoms such as N, N-dimethylaminopyridine and N-methylimidazole are preferably used (see JP-A2002-146003).
The catalyst is usually charged when the monomers are charged, and is not necessarily removed after the acylation, and transesterification can be directly performed without removing the catalyst.
Polycondensation by transesterification/amid exchange is usually performed by melt polymerization, but melt polymerization and solid-phase polymerization may be used in combination. The solid-phase polymerization is preferably carried out by a known solid-phase polymerization method after extracting the polymer in the melt polymerization step and pulverizing the polymer into powder or sheet. Specifically, for example, a method of heat-treating in a solid phase state for 1 to 30 hours at 20 to 350 ℃ in an inert atmosphere such as nitrogen is mentioned. The solid-phase polymerization may be performed while stirring or may be performed in a state of being left undisturbed. The melt polymerization vessel and the solid phase polymerization vessel can be the same reaction vessel by providing an appropriate stirring mechanism. After solid-phase polymerization, the liquid crystalline polyester obtained can be pelletized and molded by a known method. The pulverization may be performed by a known method.
The liquid crystalline polyester can be produced by using a batch apparatus, a continuous apparatus, or the like, for example.
When the liquid crystalline polyester (X) is in the form of powder, the volume average particle diameter is preferably 100 to 2000. Mu.m. The volume average particle diameter of the powdery liquid crystalline polyester (X) can be measured by a dry sieving method (for example, RPS-105 manufactured by setaren corporation).
In one aspect, the content of the component (X) is preferably 5 to 10% by mass based on the total mass of the liquid crystalline polyester liquid composition.
[ production example of liquid Crystal polyester (X) ]
To a reactor equipped with a stirrer, a torquemeter, a nitrogen inlet, a thermometer and a reflux condenser, 940.9g (5.0 mol) of 6-hydroxy-2-naphthoic acid, 377.9g (2.5 mol) of 4-hydroxyacetanilide, 415.3g (2.5 mol) of isophthalic acid and 867.8g (8.4 mol) of acetic anhydride were added, and after the gas in the reactor was replaced with nitrogen, the temperature was raised from room temperature (23 ℃) to 140℃for 60 minutes while stirring under a nitrogen stream, and refluxed at 140℃for 3 hours. Then, while removing acetic acid and unreacted acetic anhydride as by-products by distillation, it took 5 hours to raise the temperature from 150℃to 300℃and hold the temperature at 300℃for 30 minutes, and then the content was taken out of the reactor and cooled to room temperature (23 ℃). The obtained solid material was pulverized by a pulverizer to obtain a powdery liquid crystalline polyester (X-1). The flow initiation temperature of the liquid crystalline polyester (X-1) may be 193.3 ℃.
The liquid crystalline polyester (X-1) was heated to 160℃from room temperature (23 ℃) for 2 hours and 20 minutes under nitrogen atmosphere, then heated to 180℃from 160℃for 3 hours and 20 minutes, and kept at 180℃for 5 hours to perform solid-phase polymerization, and then cooled to 23℃and then pulverized by a pulverizer, whereby the liquid crystalline polyester (X-2) in the form of powder was obtained. The flow initiation temperature of the liquid crystalline polyester (X-2) may be 220 ℃.
The liquid crystalline polyester (X-2) was heated to 180℃in a nitrogen atmosphere over 1 hour and 25 minutes from room temperature, then heated to 255℃over 6 hours and 40 minutes from 180℃and held at 255℃for 5 hours, and after solid-phase polymerization, cooled to 23℃to obtain a powdery liquid crystalline polyester (X) having a volume average particle diameter of 871. Mu.m. The volume average particle diameter of the liquid crystalline polyester (X) was measured by RPS-105, manufactured by Nippon Co., ltd. The flow initiation temperature of the liquid crystalline polyester (X) may be 302 ℃.
[ preparation of liquid Crystal polyester solution (X') ]
8 parts by mass of a liquid crystalline polyester (X) was added to 92 parts by mass of N-methylpyrrolidone (boiling point (1 atm) 204 ℃ C.) and stirred at 140 ℃ C. Under nitrogen atmosphere for 4 hours, whereby a liquid crystalline polyester solution (X') was produced. The viscosity of the liquid crystalline polyester solution (X') may be 955 mPas.
Method for producing liquid crystal polyester film
The method for producing a liquid crystal polyester film according to the embodiment comprises a step of applying the liquid crystal polyester composition according to the embodiment to a support and performing a heat treatment to obtain a liquid crystal polyester film containing a liquid crystal polyester.
The manufacturing method may include the following steps.
And a step (coating step) of coating the liquid crystal polyester composition of the embodiment on a support to form a precursor of a liquid crystal polyester film on the support.
And a step (heat treatment step) of heat-treating the precursor of the liquid crystal polyester film to obtain a liquid crystal polyester film.
In the method for producing a liquid crystal polyester film, the step of coating the liquid crystal polyester composition of the embodiment on the support in the coating step may include a step of removing a medium from the coated liquid crystal polyester composition (drying step).
That is, the method for producing a liquid crystal polyester film according to the embodiment may be a step of coating the liquid crystal polyester composition according to the embodiment on a support, removing a medium from the coated liquid crystal polyester composition, and performing a heat treatment to obtain a liquid crystal polyester film containing a liquid crystal polyester.
The method for producing a liquid crystal polyester film may further include a step of separating the support from the laminate (separation step). The liquid crystal polyester film can be suitably used as a film for electronic parts even in a state where it is formed as a laminate on a support, and therefore, the separation step is not a necessary step in the production process of the liquid crystal polyester film.
An example of a method for producing a liquid crystal polyester film according to the embodiment will be described below with reference to the drawings.
Fig. 1 is a schematic view showing an example of a process for producing a liquid crystal polyester film and a laminate according to the embodiment.
First, the liquid crystal polyester composition 30 is coated on the support 12 (fig. 1 (a) coating step). The liquid crystalline polyester composition 30 comprises a liquid crystalline polyester powder 1 and a medium 3. The liquid-crystalline polyester composition can be applied to the support by a roll coating method, a dip coating method, a spray coating method, a spin coating method, a curtain coating method, a slot coating method, a screen printing method, or the like, and a method that can be applied smoothly and uniformly to the upper surface of the support can be appropriately selected. In addition, in order to uniformize the distribution of the liquid crystal polyester powder, an operation of stirring the liquid crystal polyester composition may be performed before coating.
The support 12 is preferably in the shape of a plate, sheet, or film, and examples thereof include a glass plate, a resin film, and a metal foil. Among them, a resin film or a metal foil is preferable, and particularly, a copper foil is preferable in view of excellent heat resistance, easiness of application of a liquid composition, and easiness of removal from a liquid crystal polyester film.
Examples of commercially available Polyimide (PI) films include "U-PILEX S" and "U-PILEX R" from Yu Xing, inc., tokyo, kapton, inc., and "IF30", "IF70" and "LV300" from SKC Kelong polyimide Co., ltd. The thickness of the resin film is preferably 25 μm or more and 75 μm or less, more preferably 50 μm or more and 75 μm or less. The thickness of the metal foil is preferably 3 μm or more and 75 μm or less, more preferably 5 μm or more and 30 μm or less, and still more preferably 10 μm or more and 25 μm or less.
Next, the medium 3 is removed from the liquid crystal polyester composition 30 applied on the support 12 (fig. 1 (b) drying step). The liquid crystal polyester composition from which the medium 3 is removed becomes a liquid crystal polyester film precursor 40 to be heat-treated. The medium 3 is not necessarily completely removed from the liquid crystal polyester composition, and a part of the medium contained in the liquid crystal polyester composition may be removed, or the whole medium may be removed. The proportion of the solvent contained in the liquid crystal polyester film precursor 40 is preferably 50 mass% or less, more preferably 3 mass% or more and 12 mass% or less, and still more preferably 5 mass% or more and 10 mass% or less, relative to the total mass of the liquid crystal polyester film precursor. By setting the solvent content in the liquid crystal polyester film precursor to the above lower limit value or more, the risk of lowering the thermal conductivity of the liquid crystal polyester film is reduced. In addition, by making the solvent content in the liquid crystal polyester film precursor equal to or less than the above-described upper limit value, the risk of deterioration in the appearance of the liquid crystal polyester film due to foaming or the like at the time of heat treatment is reduced.
The removal of the medium is preferably performed by evaporating the medium, and examples of the method include heating, depressurizing, and ventilating, and combinations thereof may be used. The removal of the medium may be performed continuously or individually. The removal of the medium is preferably performed under heating in a continuous manner, more preferably under heating while ventilation is performed in a continuous manner, from the viewpoint of productivity or operability. The temperature of the medium to be removed is preferably less than the melting point of the liquid crystal polyester powder, for example, 40 ℃ or more and 200 ℃ or less, preferably 60 ℃ or more and 200 ℃ or less. The time for removing the medium is suitably adjusted to, for example, 3 to 12 mass% of the medium content in the liquid crystal polyester film precursor. The time for removing the medium is, for example, 0.2 to 12 hours, preferably 0.5 to 8 hours.
The laminate precursor 22 having the support 12 and the liquid crystal polyester film precursor 40 thus obtained is subjected to heat treatment to obtain a laminate 20 having the support 12 and the liquid crystal polyester film 10 (a film obtained by heat-treating the liquid crystal polyester film precursor 40) (heat treatment step (c) in fig. 1). At this time, the liquid crystal polyester film 10 formed on the support is obtained.
The heat treatment conditions include, for example, heating from the boiling point of the medium to-50℃to a heat treatment temperature, and then heat-treating the liquid crystal polyester at a temperature equal to or higher than the melting point of the liquid crystal polyester.
In this temperature rise, although the polymerization reaction of the liquid crystal polyester may be performed by heating, the temperature rise rate up to the heat treatment temperature may be increased, so that the increase in the molecular weight of the liquid crystal polyester in the liquid crystal polyester powder may be suppressed to some extent, and the melting of the liquid crystal polyester powder may be improved, whereby a high-quality film may be easily obtained. The temperature rising rate from the boiling point of the solvent to the heat treatment temperature is preferably 3℃per minute or more, more preferably 5℃per minute or more.
The heat treatment temperature is preferably equal to or higher than the melting point of the liquid crystal polyester, more preferably equal to or higher than the melting point of the liquid crystal polyester, and still more preferably equal to or higher than the melting point of the liquid crystal polyester +5℃. The heat treatment temperature may be appropriately determined depending on the type of the liquid crystal polyester, and is preferably 230 ℃ or higher and 400 ℃ or lower, more preferably 300 ℃ or higher and 380 ℃ or lower, and still more preferably 320 ℃ or higher and 350 ℃ or lower, as an example. By performing the heat treatment at a temperature higher than the melting point of the liquid crystal polyester, the melting of the liquid crystal polyester powder becomes good, and a high-quality liquid crystal polyester film can be formed. It was confirmed that the liquid crystal polyester powder was melted by transparentizing the liquid crystal polyester film precursor 40.
The medium boiling point herein means a boiling point at a pressure at the time of temperature increase. In the case where the heating of the laminate precursor 22 is started from less than the medium boiling point of-50 ℃, the heating rate in the range from the medium boiling point of-50 ℃ to the heat treatment temperature may be determined. The time to reach the boiling point of the medium-50℃is arbitrary. In addition, the time after the heat treatment temperature was reached was regarded as the heat treatment time. The heat treatment time may be, for example, 0.5 hours or more, 1 hour or more and 24 hours or less, or 3 hours or more and 12 hours or less.
The heat treatment may be performed continuously or singly, as in the case of removing the medium, but is preferably performed continuously from the viewpoint of productivity or handleability, and more preferably performed continuously after removing the medium.
Next, by separating the liquid crystal polyester film 10 from the laminate 20 having the support 12 and the liquid crystal polyester film 10, the liquid crystal polyester film 10 can be obtained as a single-layer film (fig. 1 (d) separation step). When a glass plate is used as the support 12, the liquid crystal polyester film 10 may be separated from the laminate 20 by peeling the liquid crystal polyester film 10 from the laminate 20. In the case of using a resin film as the support 12, the resin film or the liquid crystal polyester film 10 may be peeled from the laminate 20. When a metal foil is used as the support 12, the metal foil may be etched and removed to separate the laminate 20. When a resin film, particularly a polyimide film, is used as a support, the polyimide film or the liquid crystal polyester film is easily peeled from the laminate 20, and a liquid crystal polyester film having a good appearance can be obtained. When a metal foil is used as the support, the laminate 20 can be used as a metal-clad laminate for a printed wiring board without separating the liquid crystal polyester film from the laminate 20.
According to the method for producing a liquid crystal polyester film of the embodiment, a liquid crystal polyester film excellent in isotropy can be produced.
In contrast to the conventional melt molding method in which a liquid crystal polyester film is produced by forming a melted liquid crystal polyester into a film, the above-described production method according to the embodiment is greatly different from the conventional film production method in that a liquid crystal polyester powder is previously thinly disposed on a support and then melted.
In the method for producing a liquid crystal polyester film or laminate according to the embodiment, since the liquid crystal polyester powder is arranged in a thin manner on the support in advance and is formed into a film, a liquid crystal polyester film excellent in isotropy can be produced without applying a physical force such as extrusion molding, which is an important factor for biasing the molecular orientation.
Further, by setting the number average molecular weight of the liquid crystal polyester in the liquid crystal polyester powder to a relatively small value of 10000 or less, a high-quality liquid crystal polyester film having excellent isotropy suitable for use as a film for electronic parts can be produced, which has a property suitable for coating and a good molten state of the liquid crystal polyester film at the time of heat treatment.
Further, by using a liquid crystal polyester powder having an average particle diameter of 0.5 to 20 μm as a raw material, a high-quality polyester film having a suitable thinness for use as a film for electronic parts and suppressing the occurrence of holes or through holes can be easily produced.
In addition, in the liquid crystal polyester composition, since the liquid crystal polyester powder should not be limited to be soluble in a medium, a liquid crystal polyester excellent in dielectric characteristics can be used, and a liquid crystal polyester film excellent in dielectric characteristics and isotropy can be easily obtained.
Method for producing laminate
The method for producing a laminate according to the embodiment comprises applying the liquid crystal polyester composition according to the embodiment to a support, and performing a heat treatment to form a liquid crystal polyester film containing a liquid crystal polyester, thereby obtaining a laminate comprising the support and the liquid crystal polyester film.
The manufacturing method may include the following steps.
And a step (coating step) of coating the liquid crystal polyester composition of the embodiment on a support to form a liquid crystal polyester film precursor on the support.
And a step (heat treatment step) of heat-treating the liquid crystal polyester film precursor to obtain a laminate comprising the support and the liquid crystal polyester film.
In the same manner as in the method for producing a liquid crystal polyester film described above, in the method for producing a laminate, the step of coating the liquid crystal polyester composition of the embodiment on the support in the coating step may include a step of removing the medium from the coated liquid crystal polyester composition (drying step).
That is, the method for producing a laminate of the embodiment may include a step of coating the liquid crystal polyester composition of the embodiment on a support, removing a medium from the coated liquid crystal polyester composition, and performing a heat treatment to form a liquid crystal polyester film containing a liquid crystal polyester, thereby obtaining a laminate including the support and the liquid crystal polyester film.
Fig. 1 is a schematic view showing an example of a process for producing a liquid crystal polyester film and a laminate according to the embodiment. The method for producing the laminate shown in fig. 1 is the same as that described in the above "method for producing a liquid crystal polyester film", except that the above-described separation step (fig. 1 (d)) is not performed, and therefore, the description thereof is omitted.
According to the method for producing a laminate of the embodiment, a laminate having the liquid crystal polyester film of the embodiment can be produced.
Film (S)
In the above-described method for producing a liquid crystal polyester film or laminate, although liquid crystal polyester powder is used as a raw material, a thermoplastic resin having excellent dielectric characteristics is used as a raw material instead of liquid crystal polyester, and a film having excellent dielectric characteristics and isotropy can be obtained.
Fig. 2 is a schematic diagram showing the structure of the film 11 according to the embodiment.
The film of the embodiment comprises a thermoplastic resin, has a relative dielectric constant of 3 or less at a frequency of 1GHz, a dielectric loss tangent of 0.005 or less at a frequency of 1GHz, and a molecular orientation degree (MOR) measured by a microwave orientation instrument in a range of 1 to 1.1.
The film satisfying the above-described specification has good quality as a film for electronic components. The quality standard is the relative dielectric constant, dielectric loss tangent, and molecular orientation (isotropy of the film) described above, and also the thickness and appearance (whether or not holes or through holes are generated) are considered.
As an example, the relative dielectric constant and dielectric loss tangent of the film can be controlled by the kind of thermoplastic resin. Further, as an example, the degree of isotropy of the film can be controlled by the method of producing the film.
The film of the embodiment has a relative dielectric constant of 3 or less, preferably 2.9 or less, more preferably 2.8 or less, even more preferably 2.7 or less, and particularly preferably 2.6 or less at a frequency of 1 GHz. The relative dielectric constant of the film may be 2.3 or more, may be 2.4 or more, and may be 2.5 or more.
The upper limit value and the lower limit value of the relative dielectric constant of the film can be freely combined. As an example of the numerical range of the value of the relative dielectric constant of the film, it may be 2.3 or more and 3 or less, it may be 2.4 or more and 2.9 or less, it may be 2.5 or more and 2.8 or less, it may be 2.5 or more and 2.7 or less, and it may be 2.5 or more and 2.6 or less.
The film of the embodiment has a dielectric loss tangent of 0.005 or less, preferably 0.004 or less, more preferably 0.003 or less, even more preferably 0.002 or less, and particularly preferably 0.001 or less at a frequency of 1 GHz. The dielectric loss tangent of the liquid crystal polyester film may be 0.0003 or more, may be 0.0005 or more, and may be 0.0007 or more.
The upper limit value and the lower limit value of the dielectric loss tangent of the film can be freely combined. As an example of the numerical range of the dielectric loss tangent of the film, it may be 0.0003 or more and 0.005 or less, 0.0005 or more and 0.004 or less, 0.0007 or more and 0.003 or less, 0.0007 or more and 0.002 or less, and 0.0007 or more and 0.001 or less.
The relative permittivity and dielectric loss tangent of the film at a frequency of 1GHz can be measured by a capacitance method using an impedance analyzer under the following conditions.
The film was melted by using a flow tester at 350℃and then cooled to solidify to prepare a tablet having a diameter of 1cm and a thickness of 0.5 cm. The relative dielectric constant and dielectric loss tangent of the obtained tablets at 1GHz were measured under the following conditions.
The measuring method comprises the following steps: capacity method.
Electrode model: 16453A.
Measurement environment: 23 ℃, 50% rh.
Applying a voltage: 1V.
The molecular orientation degree (MOR) of the film of the embodiment measured by a microwave orientation meter is in the range of 1 to 1.1, preferably 1 to 1.08, more preferably 1 to 1.06, and even more preferably 1 to 1.04.
The molecular orientation degree (MOR) was measured by a microwave molecular orientation instrument (for example, MOA-5012A, manufactured by Wako-Kagaku Co., ltd.). A microwave molecular orientation apparatus is an apparatus that uses the principle that the transmission intensity of microwaves in the orientation direction and the vertical direction are different according to the orientation of molecules. Specifically, while rotating the sample, a microwave having a constant frequency (using 12 GHz) was irradiated, and the intensity of the transmitted microwave, which varies with the orientation of the molecule, was measured, and the ratio of the maximum value to the minimum value thereof was designated as MOR. The interaction of a microwave electric field with a constant frequency with the dipoles that make up the molecule is related to the inner product of the two vectors. The degree of orientation is known because the microwave intensity varies with the angle at which the samples are arranged due to the anisotropy of the dielectric constant of the samples.
The film of the embodiment preferably has a linear expansion coefficient of 85 ppm/DEG C or less, more preferably 50 ppm/DEG C or less, still more preferably 40 ppm/DEG C or less, and particularly preferably 30 ppm/DEG C or less, as determined in a temperature range of 50 to 100 ℃ at a temperature rising rate of 5 ℃/min. The lower limit of the linear expansion coefficient is not particularly limited, and is, for example, 0 ppm/DEG C or more. For example, when a copper foil is laminated on a film, the coefficient of linear expansion of the copper foil is preferably a value close to 18 ppm/DEG C. That is, the linear expansion coefficient of the film according to the embodiment is preferably 0 ppm/DEG C or more and 50 ppm/DEG C or less, more preferably 10 ppm/DEG C or more and 40 ppm/DEG C or less, and still more preferably 20 ppm/DEG C or more and 30 ppm/DEG C or less. When the linear expansion coefficient differs depending on the direction or the position of the film, a higher value is used as the linear expansion coefficient of the film. The linear expansion coefficient of the film can be measured using a thermal mechanical analyzer (for example, model: TMA8310, manufactured by Nippon Cooki Co., ltd.). The film of the embodiment satisfying the above numerical range has a low linear expansion coefficient and high dimensional stability.
The film having excellent isotropy is a film having a small difference in linear expansion coefficients in different measurement directions.
In the film of the embodiment, the difference between the linear expansion coefficient of MD and the linear expansion coefficient of TD (MD-TD in the case of MD > TD and TD-MD in the case of TD > MD) is preferably 2 ppm/DEG C or less, more preferably 1 ppm/DEG C or less. In a film produced by the casting method, MD is the coating direction of the dispersion. As shown in the calculation of the difference in linear expansion coefficients, in practice, since the linear expansion coefficients in different directions need only be clarified, when MD and TD of the film are unknown, if MD is an arbitrary direction of the film and TD is a direction intersecting with MD at 90 °, the direction may be set so that the difference in linear expansion coefficients in the respective directions is the largest.
The film of the embodiment satisfying the above numerical range is excellent in isotropy of linear expansion and high in dimensional stability in the machine and transverse directions.
In the film of the embodiment, it is preferable that no hole or through hole is provided as an appearance suitable for the film for electronic components. When holes or through holes are formed, there is a possibility that plating solution may infiltrate into the holes or through holes during plating. The liquid crystal polyester film produced from the liquid crystal polyester powder of the embodiment has a good thickness as a film for electronic parts, and is a high-quality liquid crystal polyester film in which the occurrence of holes or through-holes is suppressed.
The thickness of the film according to the embodiment is not particularly limited, but a preferable thickness of the film for electronic components is preferably 5 to 50. Mu.m, more preferably 7 to 40. Mu.m, still more preferably 10 to 33. Mu.m, and particularly preferably 15 to 20. Mu.m.
In the present specification, the "thickness" is an average value of values obtained by measuring thicknesses at 10 points selected randomly according to JIS standard (K7130-1992).
By selecting a raw material resin having excellent dielectric characteristics from any thermoplastic resins, a film having excellent dielectric characteristics can be obtained.
The content of the thermoplastic resin may be 50 to 100 mass% or 80 to 95 mass% based on 100 mass% of the total mass of the film according to the embodiment.
Examples of the thermoplastic resin include polypropylene, polyamide, polyester, polysulfone, polyphenylene sulfide, polyether ketone, polycarbonate, polyphenylene oxide, and polyether imide.
From the viewpoint of having particularly excellent dielectric characteristics, liquid crystal polyesters are preferable as the thermoplastic resin. The liquid crystal polyester may be the liquid crystal polyester described in the above "liquid crystal polyester powder", and therefore, description thereof is omitted.
The content of the liquid crystal polyester may be 50 to 100 mass% or 80 to 95 mass% based on 100 mass% of the total mass of the film according to the embodiment.
When the film of the embodiment contains the liquid crystal polyester, the liquid crystal polyester of the above embodiment may be contained in an amount of more than 70% by mass and 100% by mass or less relative to 100% by mass of the total amount of the liquid crystal polyesters contained in the film, and the liquid crystal polyester of the above embodiment may be contained in an amount of 80 to 100% by mass. The liquid crystal polyester includes, for example, the liquid crystal polyesters listed in the liquid crystal polyester powder of the foregoing embodiments, the liquid crystal polyesters 1) to 4) having the structural unit represented by the above formula (1), the structural unit represented by the above formula (2) and the structural unit represented by the above formula (3), or the liquid crystal polyesters having the structural unit represented by the above formula (2) and the structural unit represented by the above formula (3).
The film of the embodiment contains a thermoplastic resin, and may be a film having a relative dielectric constant of 3 or less at a frequency of 1GHz, a dielectric loss tangent of 0.005 or less at a frequency of 1GHz, and a molecular orientation degree (MOR) measured by a microwave orientation meter in a range of 1 to 1.1 (however, in the case of containing a liquid crystal polyester as a thermoplastic resin, the content of the liquid crystal polyester soluble in an aprotic solvent is less than 5% by mass based on 100% by mass of the total of the liquid crystal polyesters).
The film of the embodiment contains a thermoplastic resin, and may be a film having a relative dielectric constant of 3 or less at a frequency of 1GHz, a dielectric loss tangent of 0.005 or less at a frequency of 1GHz, and a molecular orientation degree (MOR) measured by a microwave orientation meter in a range of 1 to 1.1 (excluding liquid crystal polyesters containing an aprotic solvent).
Here, as the liquid crystal polyester soluble in the aprotic solvent, the liquid crystal polyesters exemplified in the liquid crystal polyester powder of the embodiment may be mentioned.
The method for producing the film according to the embodiment is not particularly limited, and the film according to the embodiment can be produced by the above-described "method for producing a crystalline polyester film". In the above "method for producing a crystalline polyester film", a liquid crystal polyester is used as a raw material, but in this method, the liquid crystal polyester is understood to be any thermoplastic resin, and thus a film according to an embodiment containing any thermoplastic resin can be produced.
The film according to the embodiment can be applied to a film for electronic components such as a printed wiring board. The film according to the embodiment can be provided as a substrate (for example, a flexible substrate), a laminate (for example, a flexible copper-clad laminate), a printed board, a printed wiring board, a printed circuit board, or the like, which includes the film as an insulating material.
Laminate (laminated body)
The laminate of the embodiment includes a metal layer and the film of the embodiment laminated on the metal layer.
Fig. 3 is a schematic diagram showing the structure of a laminate 21 according to an embodiment of the present invention. The laminate 21 includes a metal layer 13 and a film 11 laminated on the metal layer 13.
The film having the laminate may be exemplified by the above-mentioned materials, and therefore, the description thereof will be omitted.
The metal layer having the laminate may be a metal foil, which is preferably used as a support in the above-mentioned "method for producing a liquid crystal polyester film" and "method for producing a laminate". Copper is preferable as the metal constituting the metal layer from the viewpoint of conductivity and cost, and copper foil is preferable as the metal foil.
The thickness of the laminate according to the embodiment is not particularly limited, but is preferably 5 to 130. Mu.m, more preferably 10 to 70. Mu.m, and still more preferably 15 to 60. Mu.m.
The method for producing the laminate according to the embodiment is not particularly limited, and the laminate according to the embodiment can be produced by the above-described "method for producing a laminate". In the above-described "method for producing a laminate", a liquid crystal polyester is used as a raw material, but in this method, the liquid crystal polyester is understood to be any thermoplastic resin, and a laminate of an embodiment having a film containing any thermoplastic resin can be produced.
The laminate of the embodiment can be suitably used for films for electronic components such as printed wiring boards.
Examples (example)
The present invention will be described in further detail with reference to the following examples, but the present invention is not limited to the following examples.
< measurement method >)
[ measurement of flow initiation temperature of liquid Crystal polyester ]
About 2g of a liquid crystal polyester was filled into a cylinder equipped with a die having a nozzle with an inner diameter of 1mm and a length of 10mm using a flow tester ("CFT-500 type" manufactured by Shimadzu corporation) at 9.8MPa (100 kg/cm 2 ) While the temperature was raised at a rate of 4℃per minute, the liquid crystal polyester was melted and extruded from a nozzle, and the temperature (FT) at which the viscosity of 4800 Pa.s (48000P) was measured.
[ determination of melting Point of liquid Crystal polyester ]
The temperature was increased at a temperature increase rate of 10℃per minute using a differential scanning calorimeter ("DSC-50" manufactured by Shimadzu corporation) to confirm the position of an endothermic peak, and the temperature at the peak position of the endothermic peak was measured as the melting point of the liquid crystal polyester.
[ determination of molecular weight of liquid Crystal polyester contained in liquid Crystal polyester Fine particle powder ]
The number average molecular weight of the liquid crystal polyester contained in the liquid crystal polyester fine particle powder was measured using a gel permeation chromatograph-multi-angle light scattering photometer (differential refractometer (manufactured by Shimadzu corporation: RID-20A), multi-angle light scattering detector (manufactured by EOS, wyatt Technology Co., ltd.), a filter column (manufactured by Shodex K-G, K-806M (2 roots), K-802 (1 roots) (phi 8.0 mm. Times.30 cm)), and solvent (pentafluorophenol/chloroform (weight ratio 35/65)). A sample solution for measurement was prepared by adding 2mg of the sample to 1.4g of pentafluorophenol, dissolving the sample at 80℃for 2 hours, cooling the solution to room temperature, adding 2.6g of chloroform, diluting the solution with a solvent (pentafluorophenol/chloroform (weight ratio: 35/65)) 2-fold, and filtering the diluted solution with a filter having a pore size of 0.45. Mu.m.
[ analysis of residual acetic acid amount contained in liquid Crystal polyester microparticle powder ]
The residual acetic acid content in the liquid crystal polyester fine particle powder was analyzed by using a headspace gas chromatography (GC-2014, manufactured by Shimadzu corporation) under an extraction condition of 120℃for 20 hours and an analysis condition of 200℃for 1 hour.
[ determination of relative permittivity and dielectric loss tangent of liquid Crystal polyester Fine particle powder ]
The liquid crystal polyester fine particle powder was melted at a temperature 5℃higher than the melting point measured by a flow tester (model "CFT-500" manufactured by Shimadzu corporation), and then cooled and solidified to prepare a tablet having a diameter of 1cm and a thickness of 0.5 cm. The relative dielectric constant and dielectric loss tangent of the obtained tablets were measured at 1GHz under the following conditions.
The measuring method comprises the following steps: capacity method (apparatus: impedance analyzer (Agilent Co., ltd.; model: E4991A)).
Electrode model: 16453A.
Measurement environment: 23 ℃, 50% rh.
Applying a voltage: 1V.
[ measurement of average particle diameter of liquid Crystal polyester Fine particle powder ]
0.01g of the liquid crystal polyester fine particle powder was weighed and dispersed in about 10g of pure water. The prepared dispersion of the liquid crystal polyester fine particle powder was dispersed for 5 minutes using ultrasonic waves. The cumulative particle size distribution based on the volume of the liquid crystal polyester fine particle powder was measured by using a scattering particle size distribution measuring apparatus (horiba, ltd. "LA-950V 2") under the condition that the refractive index of pure water was 1.333, and the average particle size (D) 50 )。
[ determination of relative permittivity and dielectric loss tangent of liquid Crystal polyester film ]
The liquid crystal polyester film was melted at 350℃using a flow tester ("CFT-500 type" manufactured by Shimadzu corporation) and then cooled and solidified to prepare a tablet having a diameter of 1cm and a thickness of 0.5 cm. The relative dielectric constant and dielectric loss tangent of the obtained tablets at 1GHz were measured under the following conditions.
The measuring method comprises the following steps: capacity method (apparatus: impedance analyzer (Agilent Co., ltd.; model E4991A)).
Electrode model: 16453A.
Measurement environment: 23 ℃, 50% rh.
Applying a voltage: 1V.
[ determination of molecular orientation degree of liquid Crystal polyester film ]
The film was cut into a 5cm square and mounted on a holder, and the degree of molecular orientation was measured using a molecular orientation meter (model: MOA-5012A, manufactured by prince measuring instruments Co., ltd.) at a frequency of 12GHz and a rotational speed of 1 rpm.
[ measurement of the coefficient of Linear expansion of liquid Crystal polyester film ]
The linear expansion coefficient was measured at a temperature-rising rate of 5℃per minute from 50℃to 100℃using a thermal mechanical analyzer (model: TMA8310, manufactured by Japanese Kogyo Co., ltd.). The flow direction (MD) and the direction perpendicular Thereto (TD) of the liquid crystal polyester film were measured. In the liquid crystal polyester film of each example or comparative example produced by the casting method, the flow direction (MD) means the coating direction of the dispersion liquid.
< manufacturing of liquid Crystal polyester microparticle powder >
Example 1
Production of liquid Crystal polyester (A)
To a reactor equipped with a stirring device, a torquemeter, a nitrogen inlet, a thermometer and a reflux condenser, 1034.99g (5.5 mol) of 2-hydroxy-6-naphthoic acid, 378.33g (1.75 mol) of 2, 6-naphthalenedicarboxylic acid, 83.07g (0.5 mol) of terephthalic acid, 272.52g (2.475 mol) of hydroquinone (0.225 mol excess to the total molar amount of 2, 6-naphthalenedicarboxylic acid and terephthalic acid), 1226.87g (12 mol) of acetic anhydride and 0.17g of 1-methylimidazole as a catalyst were added. After the gas in the reactor was replaced with nitrogen, it took 15 minutes to raise the temperature from room temperature to 145 ℃ while stirring under a nitrogen stream, and refluxed at 145 ℃ for 1 hour.
Then, while removing acetic acid and unreacted acetic anhydride as by-products by distillation, the temperature was raised from 145℃for 3 hours and 30 minutes to 310℃and maintained at 310℃for 3 hours, and then the liquid crystal polyester was taken out as a solid, and cooled to room temperature to obtain liquid crystal polyester (A).
The flow initiation temperature of the liquid crystalline polyester (A) was 268 ℃. The liquid crystal polyester (A) was pulverized by a chopper VM-16 made by the company Oriental pulverizer, inc., to obtain a powder of the liquid crystal polyester (A) having an average particle diameter of 394. Mu.m.
Production of liquid Crystal polyester microparticle powder
Next, using a jet mill (manufactured by Castanea corporation, "KJ-200", diameter of pulverizing nozzle: 4.5 mm), powder of the liquid crystal polyester (A) was pulverized at a classification rotor rotation speed of 10000rpm, a pulverizing nozzle pressure of 0.64MPa and a treatment speed of 2.1 kg/hr, thereby obtaining liquid crystal polyester fine particle powder of example 1. The average particle diameter of the liquid crystal polyester fine particle powder was 8. Mu.m. Further, the melting point of the liquid crystal polyester fine particle powder of example 1 was measured by using a differential scanning calorimeter and found to be 290 ℃.
Example 2
The liquid-crystalline polyester fine particle powder of example 2 was obtained in the same manner as in the production of the liquid-crystalline polyester fine particle powder of example 1, except that the treatment conditions of the jet mill (KJ-200 manufactured by Castanea) were set to 10000rpm of the classifying rotor, 0.63MPa of the pulverizing nozzle pressure, and 2.6 kg/hr of the treatment speed, and the liquid-crystalline polyester powder was pulverized. The average particle diameter of the liquid crystal polyester fine particle powder was 10. Mu.m.
Example 3
The liquid-crystalline polyester fine particle powder of example 3 was obtained in the same manner as in the production of the liquid-crystalline polyester fine particle powder of example 1, except that the treatment conditions of the jet mill (KJ-200 manufactured by Castanea) were set to 10000rpm of the classifying rotor, 0.60MPa of the pulverizing nozzle pressure, and 4.0 kg/hr of the treatment speed, and the liquid-crystalline polyester powder was pulverized. The average particle diameter of the liquid crystal polyester fine particle powder was 15. Mu.m.
Comparative example 1
A liquid crystal polyester fine particle powder of comparative example 1 was obtained in the same manner as in the production of the liquid crystal polyester fine particle powder of example 1, except that a freezing/impact Mill (Linrex Mill, made by fine singer, singer) was used instead of the jet Mill, and the liquid crystal polyester powder was pulverized at a treatment rate of 10 kg/hour. The average particle diameter of the liquid crystal polyester fine particle powder was 27. Mu.m.
Comparative example 2
Production of liquid Crystal polyester (D)
The powder of the liquid crystalline polyester (a) obtained in example 1 was filled into SUS (stainless steel) trays, and heat treatment was performed at 290 ℃ for 6 hours to obtain a liquid crystalline polyester (D).
Production of liquid Crystal polyester microparticle powder
Next, liquid crystal polyester fine particle powder of comparative example 2 was obtained in the same manner as in the production of the liquid crystal polyester fine particle powder of example 1, except that the powder of the liquid crystal polyester (D) was pulverized by using a jet mill (KJ-200 manufactured by chestnut iron work) at a classification rotor rotation speed of 10000rpm, a pulverizing nozzle pressure of 0.60MPa, and a processing speed of 0.1 kg/hour. The average particle diameter of the liquid crystal polyester fine particle powder was 7. Mu.m.
The relative dielectric constant and dielectric loss tangent of each of the obtained liquid crystal polyester fine powder were measured.
Table 1 shows the above items and measurement results thereof.
< manufacturing of liquid Crystal polyester film >
Examples 1-1 to 3-1 and comparative examples 1-1 to 2-1
Preparation of the Dispersion
8 parts by weight of each of the liquid crystal polyester fine particle powders of examples 1 to 3 and comparative examples 1 to 2 was added to 92 parts by weight of N-methyl-2-pyrrolidone (boiling point (1 atm) 204 ℃ C.), and the mixture was stirred using a stirring deaerator AR-500 made by Xinji corporation to obtain each of the dispersions.
Production of liquid Crystal polyester film
Each of the above dispersions was cast on a roughened surface of a copper foil (3 EC-VLP,18 μm, manufactured by three-well metal mining) using a micrometer-equipped applicator (SA 204 of shenen) and an automatic applicator (type I of detection machine industry co., ltd.) to give a cast film having a thickness of 300 μm, and then dried at 40 ℃ and normal pressure (1 atm) for 4 hours to remove the solvent from the cast film. In comparative example 2-1, the dispersion became gel-like and could not be cast, and thus could not be formed into a film.
After the above-mentioned drying, the temperature was further raised from room temperature to 310℃at 7℃per minute in a hot air oven under a nitrogen atmosphere, and the mixture was kept at that temperature for 6 hours to perform heat treatment, thereby obtaining a liquid crystal polyester film with copper foil.
The obtained liquid crystal polyester film with copper foil was immersed in an aqueous solution of ferric chloride, and the copper foil was removed by etching, thereby obtaining a single-layer film.
The appearance of each film was confirmed. The liquid crystal polyester film of comparative example 1-1 was unsuitable as a film for electronic parts because a large number of holes were formed in the surface and the appearance was poor.
Table 1 shows the above items and measurement results thereof.
TABLE 1
Figure GDA0003195692860000381
No film can be made
In comparative example 2-1, in which the liquid crystal polyester fine particle powder of comparative example 2 containing a liquid crystal polyester having a number average molecular weight of not more than 10000 was used as a raw material, a liquid crystal polyester film could not be produced. In contrast, the liquid crystal polyester films of examples 1-1 to 3-1 were produced by using the liquid crystal polyester fine particle powders of examples 1 to 3 containing a liquid crystal polyester having a number average molecular weight of 10000 or less as a raw material.
In addition, the liquid crystal polyester film of comparative example 1-1 produced from the liquid crystal polyester fine particle powder of comparative example 1 having an average particle diameter not satisfying the range of 0.5 to 20 μm was poor in appearance, and a large number of pores were generated on the surface. In contrast, the liquid crystal polyester films of examples 1-1 to 3-1 produced from the liquid crystal polyester fine particle powders of examples 1 to 3 satisfying the average particle diameter range of 0.5 to 20 μm were thin and also excellent in appearance.
The results of evaluating the appearance of the liquid crystal polyester films of examples 1-1 to 3-1 and comparative example 1-1 were shown in Table 1 as "G", and those showing no occurrence of holes and excellent appearance were shown as "F".
< manufacturing of liquid Crystal polyester film >
The liquid crystal polyester films of examples 1-1 to 1-5 were produced by changing the heat treatment conditions using the liquid crystal polyester fine particle powder of the liquid crystal polyester (A) obtained in example 1 as a raw material. The liquid crystal polyester film of example 1-1 was obtained by the same production method as that of example 1-1.
Examples 1 to 1
Preparation of the Dispersion
8 parts by weight of the fine liquid crystal polyester powder of the liquid crystal polyester (A) produced in example 1 was poured into 92 parts by weight of N-methyl-2-pyrrolidone, and stirred using a stirring and deaerating machine AR-500 manufactured by Sangyo Co., ltd.
Production of liquid Crystal polyester film
Each of the above-mentioned dispersions was cast on a roughened surface of a copper foil (3 EC-VLP,18 μm) to a thickness of 300 μm using a micrometer-equipped film coater (SA 204 of shenen corporation) and an automatic coater (type I of detection machine industry co.) and then dried at 40 ℃ for 4 hours under normal pressure (1 atm), thereby removing the solvent from the cast film.
After the above-mentioned drying, the temperature was further raised from room temperature to 310℃at 7℃per minute in a hot air oven under a nitrogen atmosphere, and the temperature was maintained for 6 hours to conduct heat treatment, thereby obtaining a liquid crystal polyester film with copper foil of example 1-1.
Examples 1 to 2
The liquid crystal polyester film with copper foil of example 1-2 was obtained in the same manner as the production of the liquid crystal polyester film with copper foil of example 1-1 described above, except that the above heat treatment conditions were changed to rise from room temperature to 330℃at 7℃per minute.
Examples 1 to 3
The liquid crystal polyester films with copper foil of examples 1-3 were obtained in the same manner as the production of the liquid crystal polyester film with copper foil of example 1-1 described above, except that the above heat treatment conditions were changed to a temperature rise from room temperature to 310℃at 4℃per minute.
Examples 1 to 4
The liquid crystal polyester films with copper foil of examples 1 to 4 were obtained in the same manner as the production of the liquid crystal polyester film with copper foil of example 1 to 1 described above, except that the above heat treatment conditions were changed to a temperature rise from room temperature to 300℃at 7℃per minute.
Examples 1 to 5
The liquid crystal polyester films with copper foil of examples 1 to 5 were obtained in the same manner as the production of the liquid crystal polyester film with copper foil of example 1 to 1 described above, except that the above heat treatment conditions were changed to a temperature rise from room temperature to 310℃at 3℃per minute.
Comparative example 3
A liquid crystal polyester film of comparative example 3 was produced as follows, using a liquid crystal polyester soluble in an organic solvent as a raw material.
Production of liquid Crystal polyester (B)
To a reactor equipped with a stirrer, a torquemeter, a nitrogen inlet, a thermometer and a reflux condenser, 940.9g (5.0 mol) of 6-hydroxy-2-naphthoic acid, 377.9g (2.5 mol) of 4-hydroxyacetanilide, 415.3g (2.5 mol) of isophthalic acid and 867.8g (8.4 mol) of acetic anhydride were added, and after the gas in the reactor was replaced with nitrogen, the temperature was raised from room temperature to 140℃for 60 minutes under stirring under a nitrogen flow, and refluxed at 140℃for 3 hours.
Then, while removing acetic acid and unreacted acetic anhydride as by-products by distillation, it took 5 hours to raise the temperature from 150℃to 300℃and hold the temperature at 300℃for 30 minutes, and then the content was taken out of the reactor and cooled to room temperature. The obtained solid matter was pulverized with a pulverizer to obtain a powdery liquid crystal polyester (B1). The flow initiation temperature of the liquid-crystalline polyester (B1) was 193.3 ℃.
The liquid-crystalline polyester (B1) obtained above was heated to 160 ℃ in a nitrogen atmosphere over 2 hours and 20 minutes from room temperature, then heated to 180 ℃ over 3 hours and 20 minutes from 160 ℃ and held at 180 ℃ for 5 hours, subjected to solid-phase polymerization, cooled, and then pulverized by a pulverizer to obtain a powdery liquid-crystalline polyester (B2). The flow initiation temperature of the liquid-crystalline polyester (B2) was 220 ℃.
The liquid-crystalline polyester (B2) obtained above was heated to 180 ℃ in a nitrogen atmosphere over 1 hour and 25 minutes from room temperature, then heated to 255 ℃ over 6 hours and 40 minutes from 180 ℃ and held at 255 ℃ for 5 hours to perform solid-phase polymerization and then cooled, whereby a powdery liquid-crystalline polyester (B) was obtained. The flow initiation temperature of the liquid-crystalline polyester (B) was 302 ℃. Further, the melting point of the liquid crystal polyester (B) was measured by a differential scanning calorimeter and found to be 311 ℃.
Preparation of liquid Crystal polyester solutions
8 parts by mass of a liquid crystalline polyester (B) was added to 92 parts by mass of N-methylpyrrolidone (boiling point (1 atm) 204 ℃ C.) and stirred at 140 ℃ C. Under nitrogen atmosphere for 4 hours to prepare a liquid crystalline polyester solution. The viscosity of the liquid-crystalline polyester solution was 955 mPas.
Production of liquid Crystal polyester film
The liquid crystal polyester solution was cast on a roughened surface of a copper foil (3 EC-VLP,18 μm, manufactured by Mitsui metal mining) using a micrometer-equipped applicator (SA 204 of Homex Co., ltd.) and an automatic applicator (type I of Mitsui Co., ltd.) to give a cast film having a thickness of 300 μm, and then dried at 40℃under normal pressure (1 atm) for 4 hours to remove the solvent from the cast film. Further, casting was performed on the surface of the dried liquid crystal polyester (B) for the second time so that the thickness of the casting film was 300 μm, and the solvent was removed from the casting film by drying at 40℃under normal pressure (1 atm) for 4 hours.
After the above-mentioned drying, the temperature was further raised from room temperature to 270℃at 1℃per minute in a hot air oven under a nitrogen atmosphere, and the heat treatment was carried out for 2 hours under the temperature condition, thereby obtaining a liquid crystal polyester film with copper foil of comparative example 3.
Comparative example 4
Production of liquid Crystal polyester (C)
The powder of the liquid crystal polyester (a) obtained in example 1 above was filled into SUS trays, and heat treatment was performed at 280 ℃ for 6 hours, thereby obtaining a liquid crystal polyester (C). The flow initiation temperature of the obtained liquid-crystalline polyester (C) was 306 ℃.
Production of liquid Crystal polyester film
100 parts by weight of the obtained liquid-crystalline polyester (C) was pelletized at 325℃using a twin screw extruder (product of Mitsui iron Co., ltd. "PCM-30"), to obtain pellets. Further, the melting point of the particles was measured by a differential scanning calorimeter and found to be 319 ℃.
After the obtained pellets were melt-extruded by a single screw extruder, a ring-shaped inflation die having a die diameter of 30mm and a slit spacing of 0.25mm was used for inflation film formation. In this case, a filtration device (leaf disc filter, manufactured by japan fine yarn company) connected to the inlet of the annular inflation die was used to filter the dissolved liquid crystal polyester and form a film. The Filter device was laminated with 16 resistant dragon filters (NASLON filters) LF4-0 NF2M-05D2 (manufactured by Japanese Seiko Co., ltd., filtration accuracy 5.0 μm, leaf disk type).
From an annular inflation die heated to 340 ℃, extrusion was performed under the condition that the draw ratio of TD was 4.3 with respect to the draw ratio of MD, thereby obtaining a liquid crystal polyester film of comparative example 4.
The liquid crystal polyester films with copper foil obtained in examples 1-1 to 1-5 and comparative examples 3 to 4 were immersed in an aqueous solution of ferric chloride, and the copper foil was etched away, thereby obtaining a single-layer film.
Table 2 shows the above items and measurement results thereof.
TABLE 2
Figure GDA0003195692860000421
The left column indicates the value of the linear expansion coefficient of MD, and the right column indicates the value of the linear expansion coefficient of TD.
Since the liquid crystal polyester films of examples 1-1 to 1-5 were obtained by casting a dispersion of liquid crystal polyester fine particle powder on a copper foil and then performing a heat treatment (abbreviated as "dispersion casting" in the table), they were excellent in dielectric characteristics and low in molecular orientation degree (MOR), and had excellent properties.
Since the liquid crystal polyester film of comparative example 3 is obtained by casting a solution of the liquid crystal polyester fine particle powder on a copper foil (simply referred to as "solution casting" in the table), there is a limit in the solution casting method that the liquid crystal polyester soluble in the solvent is used as a raw material, and thus there is a tendency that the dielectric characteristics are poor.
Since the liquid crystal polyester film of comparative example 4 was obtained by the inflation method, the molecular orientation degree (MOR) tends to be high, and the linear expansion of MD and TD also varies.
Each configuration and combination of these in each embodiment are examples, and the addition, omission, substitution, and other modification of the configuration can be made without departing from the scope of the present invention. The present invention is not limited to the embodiments, but is limited only by the scope of the claims (claim).
Description of the reference numerals
1: liquid crystal polyester powder; 3: a medium; 30: a liquid crystalline polyester composition; 10: a liquid crystal polyester film; 11: a membrane; 12: a support body; 13: a metal layer; 20. 21: a laminate; 22: a laminate precursor; 40: a liquid crystal polyester film precursor.

Claims (8)

1. A liquid-crystalline polyester composition comprising a medium and a liquid-crystalline polyester powder insoluble in the medium, wherein,
the liquid crystal polyester powder comprises a liquid crystal polyester having a number average molecular weight of 10000 or less,
and the average particle diameter of the liquid crystal polyester powder is 0.5 to 20 mu m.
2. The liquid crystalline polyester composition according to claim 1, wherein,
the relative dielectric constant of the liquid crystal polyester powder at a frequency of 1GHz is 3 or less, and the dielectric loss tangent of the liquid crystal polyester powder at a frequency of 1GHz is 0.005 or less.
3. The liquid-crystalline polyester composition according to claim 1 or 2, wherein,
the liquid crystal polyester has a structural unit containing a naphthalene structure.
4. The liquid-crystalline polyester composition according to claim 3, wherein,
the content of the structural unit containing a naphthalene structure is 40 mol% or more with respect to 100 mol% of the total of all structural units in the liquid crystal polyester.
5. The liquid-crystalline polyester composition according to claim 3, wherein,
the liquid crystal polyester has a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3),
(1)-O-Ar 1 -CO-
(2)-CO-Ar 2 -CO-
(3)-O-Ar 3 -O-
Ar 1 represents 2, 6-naphthalenediyl, 1, 4-phenylene, or 4,4' -biphenylene; ar (Ar) 2 And Ar is a group 3 Each independently represents 2, 6-naphthalenediyl, 2, 7-naphthalenediyl, 1, 4-phenylene, 1, 3-phenylene or 4,4' -biphenylene; from Ar 1 、Ar 2 Or Ar 3 The hydrogen atoms in the groups are independently substituted or not substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms.
6. The liquid-crystalline polyester composition according to claim 1 or 2, wherein,
the medium is an aprotic solvent.
7. A method for producing a liquid crystal polyester film, wherein,
the method for producing the liquid crystal polyester film comprises the following steps: a process for preparing a liquid-crystalline polyester film comprising the liquid-crystalline polyester by applying the liquid-crystalline polyester composition according to any one of claims 1 to 6 to a support and heat-treating the applied liquid-crystalline polyester composition.
8. A method for producing a laminate, wherein,
the method for producing the laminate comprises: a process for producing a laminate comprising the support and the liquid crystal polyester film, wherein the liquid crystal polyester composition according to any one of claims 1 to 6 is applied to the support and heat-treated to form a liquid crystal polyester film containing a liquid crystal polyester.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004196930A (en) * 2002-12-18 2004-07-15 Sumitomo Chem Co Ltd Aromatic liquid crystal polyester and its film
JP2006225641A (en) * 2005-01-18 2006-08-31 Sumitomo Chemical Co Ltd Liquid crystalline polyester and film using the same
JP2011213802A (en) * 2010-03-31 2011-10-27 Sumitomo Chemical Co Ltd Method for producing liquid-crystalline polyester powder
CN111886294A (en) * 2018-03-20 2020-11-03 住友化学株式会社 Liquid crystalline polyester liquid composition, method for producing liquid crystalline polyester film, and liquid crystalline polyester film

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100929383B1 (en) * 2007-05-23 2009-12-02 삼성정밀화학 주식회사 Aromatic liquid crystal polyester amide copolymer, prepreg employing the above-mentioned aromatic liquid crystal polyester amide copolymer, laminate and printed wiring board employing the prepreg
JP2011096471A (en) * 2009-10-29 2011-05-12 Sumitomo Chemical Co Ltd Cable for mobile phone with shield layer
KR102483625B1 (en) 2015-10-01 2023-01-02 삼성전기주식회사 Resin composition having low dielectric constant, insulating film using the same and printed circuit board comprising the film

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004196930A (en) * 2002-12-18 2004-07-15 Sumitomo Chem Co Ltd Aromatic liquid crystal polyester and its film
JP2006225641A (en) * 2005-01-18 2006-08-31 Sumitomo Chemical Co Ltd Liquid crystalline polyester and film using the same
JP2011213802A (en) * 2010-03-31 2011-10-27 Sumitomo Chemical Co Ltd Method for producing liquid-crystalline polyester powder
CN111886294A (en) * 2018-03-20 2020-11-03 住友化学株式会社 Liquid crystalline polyester liquid composition, method for producing liquid crystalline polyester film, and liquid crystalline polyester film

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