CN116669950A

CN116669950A - Liquid crystal polymer film, and laminate

Info

Publication number: CN116669950A
Application number: CN202280009811.0A
Authority: CN
Inventors: 佐佐田泰行
Original assignee: Fujifilm Corp
Current assignee: Fujifilm Corp
Priority date: 2021-02-18
Filing date: 2022-02-16
Publication date: 2023-08-29
Also published as: WO2022176914A1; TW202243911A; JPWO2022176914A1; KR20230116047A

Abstract

The present invention provides a liquid crystal polymer film and a laminate using the liquid crystal polymer film, wherein the liquid crystal polymer film comprises: a liquid crystal polymer layer comprising a liquid crystal polymer; and a layer A disposed on at least one surface of the liquid crystal polymer layer, wherein a mixed region containing the liquid crystal polymer and a material constituting the layer A is formed between the liquid crystal polymer layer and the layer A.

Description

Liquid crystal polymer film, and laminate

Technical Field

The present invention relates to a liquid crystal polymer film, a polymer film, and a laminate.

Background

In recent years, frequencies used in communication apparatuses tend to become very high. In order to suppress transmission loss in a high frequency band, it is required to reduce the relative dielectric constant and dielectric loss tangent of an insulating material used in a circuit substrate.

Conventionally, polyimide has been used in many cases as an insulating material for a circuit board, but a liquid crystal polymer having high heat resistance and low water absorption and having a small loss in a high frequency band has been attracting attention.

As a conventional liquid crystal polymer film, for example, japanese patent application laid-open No. 2020-26474 discloses a liquid crystal polyester film comprising at least a liquid crystal polyester, wherein when the 1 st degree of orientation is set to the 1 st degree of orientation with respect to the direction parallel to the main surface of the liquid crystal polyester film and the 2 nd degree of orientation is set to the 2 nd degree of orientation parallel to the main surface and orthogonal to the 1 st direction, the ratio of the 1 st degree of orientation to the 2 nd degree of orientation, i.e., the 1 st degree of orientation/the 2 nd degree of orientation, is 0.95 to 1.04, and the 3 rd degree of orientation of the liquid crystal polyester measured by a wide angle X-ray scattering method in the direction parallel to the main surface is 60.0% or more. In order to improve adhesion between the liquid crystal polymer film and other layers, there have been proposed methods of performing surface treatments such as plasma treatment (for example, refer to japanese unexamined patent application publication No. 2001-049002) and UV treatment (for example, refer to japanese unexamined patent application publication No. 2000-233672).

Disclosure of Invention

Technical problem to be solved by the invention

However, even with these methods, sufficient adhesion cannot be obtained.

According to the embodiment of the present invention, a liquid crystal polymer film excellent in adhesion to a layer formed on the liquid crystal polymer film can be provided.

Further, according to an embodiment of the present invention, a laminate using the liquid crystal polymer film can be provided.

Further, according to the embodiment of the present invention, a polymer film excellent in adhesion to a layer formed on the polymer film can be provided.

Means for solving the technical problems

The following means are included in the means for solving the above problems.

<1> a liquid crystal polymer film comprising: a liquid crystal polymer layer comprising a liquid crystal polymer; and a layer A disposed on at least one surface of the liquid crystal polymer layer, wherein a mixed region containing the liquid crystal polymer and a material constituting the layer A is formed between the liquid crystal polymer layer and the layer A.

<2> the liquid crystal polymer film according to <1>, wherein the average thickness of the mixed region is 1nm to 10 μm.

<3> the liquid crystal polymer film according to <1> or <2>, wherein the dielectric loss tangent is 0.005 or less.

<4> the liquid crystal polymer film according to any one of <1> to <3>, wherein layer a is an adhesive layer containing an adhesive.

<5> the liquid crystal polymer film according to <4>, wherein the adhesive comprises a compound having a functional group of at least 1 selected from the group consisting of a group capable of covalent bonding, a group capable of ionic bonding, a group capable of hydrogen bonding, and a group capable of dipole-to-dipole interaction.

<6> the liquid crystal polymer film according to <5>, wherein the functional group is a group capable of covalent bonding.

<7> the liquid crystal polymer film according to <6>, wherein the group capable of covalent bonding is at least 1 selected from the group consisting of epoxy group, oxetanyl group, isocyanate group, acid anhydride group, carbodiimide group, N-hydroxy ester group, glyoxal group, imide ester group, halogenoalkyl group and thiol group.

<8> the liquid crystal polymer film according to <5>, wherein the functional group is an ion-bondable group, a hydrogen-bondable group or a group capable of dipole-dipole interaction.

<9> the liquid crystal polymer film according to any one of <1> to <8>, wherein the melting point of the liquid crystal polymer is 280 ℃ or higher.

<10> the liquid crystal polymer film according to any one of <1> to <9>, wherein the liquid crystal polymer comprises a structural unit derived from an aromatic hydroxycarboxylic acid.

<11> the liquid crystal polymer film according to any one of <1> to <10>, wherein the liquid crystal polymer comprises at least 1 structural unit selected from the group consisting of structural units derived from an aromatic hydroxycarboxylic acid, structural units derived from an aromatic diol, and structural units derived from an aromatic dicarboxylic acid.

<12> the liquid crystal polymer film according to any one of <1> to <11>, wherein the liquid crystal polymer comprises an aromatic polyester amide.

<13> a laminate having the liquid crystal polymer film according to any one of <1> to <12>, and a metal layer or a metal wiring arranged on at least one face of the liquid crystal polymer film.

<14> the laminate according to <13>, wherein the metal layer or the metal wiring has a group capable of interacting with the liquid crystal polymer film on a side surface in contact with the liquid crystal polymer film.

<15> the laminate according to <14>, wherein the group capable of interacting with the liquid crystal polymer film is an amino group.

<16> the laminate according to any one of <13> to <15>, wherein the peel strength between the liquid crystal polymer film and the metal layer is 0.5kN/m or more.

<17> a polymer film comprising: a polymer layer containing at least 1 polymer selected from the group consisting of a fluorine-based polymer, a polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond, a polyphenylene ether, and an aromatic polyether ketone; and a layer A disposed on at least one surface of the polymer layer, wherein a mixed region including the polymer and a material constituting the layer A is formed between the polymer layer and the layer A.

Effects of the invention

According to an embodiment of the present invention, a liquid crystal polymer film excellent in adhesion to a layer formed on the liquid crystal polymer film can be provided.

Further, according to another embodiment of the present invention, a laminate using the liquid crystal polymer film can be provided.

Further, according to another embodiment of the present invention, a polymer film excellent in adhesion to a layer formed on the polymer film can be provided.

Detailed Description

The following describes the present invention in detail. The following description of the constituent elements is made in accordance with the representative embodiment of the present invention, but the present invention is not limited to this embodiment.

In the present specification, "to" representing a numerical range means that the numerical values described before and after the numerical values are used as the lower limit value and the upper limit value.

In the numerical ranges described in stages in the present invention, the upper limit or the lower limit described in one numerical range may be replaced with the upper limit or the lower limit of the numerical range described in other stages. In the numerical ranges described in the present invention, the upper limit or the lower limit of the numerical range may be replaced with the values shown in the examples.

In the description of the group (atomic group), the expression that is unsubstituted or substituted includes not only the expression that does not have a substituent but also the expression that has a substituent. For example, "alkyl" includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

In the present specification, "(meth) acrylic acid" is a term used in a concept including both acrylic acid and methacrylic acid, and "(meth) acryl" is a term used in a concept including both acryl and methacryl.

The term "step" in the present specification includes not only an independent step but also a step in which the required purpose of the step is achieved even when the step cannot be clearly distinguished from other steps. In the present invention, "mass%" and "weight%" have the same meaning, and "parts by mass" and "parts by weight" have the same meaning.

Further, in the present invention, a combination of 2 or more preferred embodiments is a more preferred embodiment.

The weight average molecular weight (Mw) and the number average molecular weight (Mn) in the present invention are the molecular weights obtained as follows unless otherwise specified: the sample was measured by a Gel Permeation Chromatography (GPC) analyzer using a column of TSKgel GMHxL, TSKgel G4000HxL, and TSKgel G2000HxL (both manufactured by TOSOH CORPORATION trade name), and converted using a solvent THF (tetrahydrofuran) and a differential refractometer, and polystyrene was used as a standard substance.

The present invention will be described in detail below.

[ liquid Crystal Polymer film ]

The liquid crystal polymer film according to the present invention comprises: a liquid crystal polymer layer comprising a liquid crystal polymer; and a layer A disposed on at least one surface of the liquid crystal polymer layer, wherein a mixed region containing the liquid crystal polymer and a material constituting the layer A is formed between the liquid crystal polymer layer and the layer A.

The present inventors have found that the adhesion between a conventional liquid crystal polymer film and a layer formed on the liquid crystal polymer film is insufficient.

As a result of intensive studies, the present inventors have found that by adopting the above-described configuration, a liquid crystal polymer film excellent in adhesion to a layer formed on the liquid crystal polymer film can be provided.

In the liquid crystal polymer film according to the present invention, in particular, since the mixed region including the liquid crystal polymer and the material constituting the layer a is formed, interlayer peeling between the liquid crystal polymer layer and the layer a is suppressed, and adhesion between the liquid crystal polymer layer and the layer a is improved. Further, in the case where the layer a contains, as the adhesive, a compound having a functional group which is at least 1 group selected from the group consisting of groups capable of undergoing covalent bonding, ionic bonding, hydrogen bonding, and dipole-dipole interaction with the surface of the layer formed on the liquid crystal polymer film, it is presumed that the adhesion between the layer a and the layer formed on the liquid crystal polymer film can be improved, and thus the adhesion with the layer formed on the liquid crystal polymer film as a whole is excellent.

< liquid Crystal Polymer layer >

In the liquid crystal polymer film according to the present invention, the liquid crystal polymer layer contains a liquid crystal polymer.

In the present invention, the type of the liquid crystal polymer is not particularly limited, and a known liquid crystal polymer can be used.

The liquid crystal polymer may be a thermotropic liquid crystal polymer exhibiting liquid crystallinity in a molten state, or may be a lyotropic liquid crystal polymer exhibiting liquid crystallinity in a solution state. In the case where the liquid crystal polymer is a thermotropic liquid crystal, the liquid crystal polymer is preferably melted at a temperature of 450 ℃ or less.

Examples of the liquid crystal polymer include liquid crystal polyesters, liquid crystal polyester amides in which an amide bond is introduced into the liquid crystal polyesters, liquid crystal polyester ethers in which an ether bond is introduced into the liquid crystal polyesters, and liquid crystal polyester carbonates in which a carbonate bond is introduced into the liquid crystal polyesters.

The liquid crystal polymer is preferably a polymer having an aromatic ring, more preferably an aromatic polyester or an aromatic polyester amide, and even more preferably an aromatic polyester amide, from the viewpoints of liquid crystal property and thermal expansion coefficient.

The liquid crystal polymer may be a polymer in which an isocyanate-derived bond such as an imide bond, a carbodiimide bond, or a isocyanurate bond is further introduced into the aromatic polyester or the aromatic polyester amide.

The liquid crystal polymer is preferably a wholly aromatic liquid crystal polymer obtained by using only an aromatic compound as a raw material monomer.

Examples of the liquid crystal polymer include the following.

1) A liquid crystal polymer obtained by polycondensing (i) an aromatic hydroxycarboxylic acid, (ii) an aromatic dicarboxylic acid, and (iii) at least 1 compound selected from the group consisting of an aromatic diol, an aromatic hydroxylamine, and an aromatic diamine.

2) A liquid crystal polymer obtained by polycondensing a plurality of aromatic hydroxycarboxylic acids.

3) A liquid crystal polymer obtained by polycondensing (i) an aromatic dicarboxylic acid and (ii) at least 1 compound selected from the group consisting of an aromatic diol, an aromatic hydroxylamine and an aromatic diamine.

4) A liquid crystal polymer obtained by polycondensing (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 each be independently used as a polycondensable derivative thereof 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 derivative (ester) obtained by converting a carboxyl group into an alkoxycarbonyl group or an aryloxycarbonyl group, a group (acid halide) obtained by converting a carboxyl group into a haloformyl group, and a group (acid anhydride) obtained by converting a carboxyl group into an acyloxycarbonyl group.

Examples of the polymerizable derivative of a compound having a hydroxyl group such as an aromatic hydroxycarboxylic acid, an aromatic diol, and an aromatic hydroxylamine include a compound (acylate) obtained by acylating a hydroxyl group to convert it into an acyloxy group.

Examples of the polymerizable derivative of the compound having an amino group such as an aromatic hydroxylamine and an aromatic diamine include a compound (acylate) obtained by acylating an amino group to convert the amino group to an amido group.

From the viewpoints of liquid-crystalline property, dielectric loss tangent of the polymer film, and adhesion to metal, the liquid-crystalline polymer preferably contains a structural unit derived from an aromatic hydroxycarboxylic acid.

In view of liquid crystal properties, dielectric loss tangent of the polymer film, and adhesion to metal, the liquid crystal polymer preferably contains at least 1 structural unit selected from the group consisting of structural units derived from aromatic hydroxycarboxylic acids, structural units derived from aromatic diols, and structural units derived from aromatic dicarboxylic acids.

The liquid crystal polymer preferably has a structural unit represented by any one of the following formulas (1) to (3) (hereinafter, a structural unit represented by the formula (1) or the like is sometimes referred to as a unit (1) or the like), more preferably has a structural unit represented by the formula (1), and particularly preferably has a structural unit represented by the formula (1), a structural unit represented by the formula (2), and a structural unit represented by the formula (2).

Formula (1) -O-Ar ¹ -CO-

Formula (2) -CO-Ar ² -CO-

Formula (3) -O-Ar ³ -O-

Ar in the formulae (1) to (3) ¹ Represents phenylene, naphthylene or biphenylene, ar ² Ar and Ar ³ Each independently represents a phenylene group, a naphthylene group, a biphenylene group, or a group represented by the following formula (4), represented by Ar ¹ ～Ar ³ The hydrogen atoms in the above groups represented may each be independently substituted with a halogen atom, an alkyl group or an aryl group.

(4) -Ar ⁴ -Z-Ar ⁵ -

Ar in formula (4) ⁴ Ar and Ar ⁵ Each independently represents a phenylene group or a naphthylene group, and Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group or an alkylene group.

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 methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-hexyl, 2-ethylhexyl, n-octyl and n-decyl, and the number of carbon atoms is preferably 1 to 10.

Examples of the aryl group include phenyl, o-tolyl, m-tolyl, p-tolyl, 1-naphthyl and 2-naphthyl groups, and the number of carbon atoms is preferably 6 to 20.

In the case where the above hydrogen atoms are substituted with these groups, ar is used for each ¹ 、Ar ² Or Ar ³ The number of the above groups is preferably 2 or less, more preferably 1, independently of each other.

Examples of the alkylene group include methylene, 1-ethanediyl, 1-methyl-1, 1-ethanediyl, 1-butanediyl and 2-ethyl-1, 1-hexanediyl, and the number of carbon atoms is preferably 1 to 10.

The unit (1) is a structural unit derived from a predetermined aromatic hydroxycarboxylic acid.

As the unit (1), ar is preferable ¹ Structural units derived from p-hydroxybenzoic acid (structural units derived from p-phenylene) and Ar ¹ Structural units which are 2, 6-naphthylene (structural units derived from 6-hydroxy-2-naphthoic acid) or Ar ¹ Structural units which are 4,4 '-biphenylene (structural units derived from 4' -hydroxy-4-biphenylcarboxylic acid)) More preferably Ar ¹ Is a structural unit of p-phenylene or 2, 6-naphthylene.

The unit (2) is a structural unit derived from a predetermined aromatic dicarboxylic acid.

As the unit (2), ar is preferable ² Structural units (structural units derived from terephthalic acid) which are p-phenylene, ar ² Structural units which are m-phenylene (structural units derived from isophthalic acid), ar ² Structural units which are 2, 6-naphthylene (structural units derived from 2, 6-naphthalenedicarboxylic acid) or Ar ² Structural units which are diphenyl ether-4, 4 '-diyl (structural units derived from diphenyl ether-4, 4' -dicarboxylic acid), more preferably Ar ² Is a structural unit of p-phenylene or 2, 6-naphthylene.

The unit (3) is a structural unit derived from a predetermined aromatic diol.

As the unit (3), ar is preferable ³ Structural units (structural units derived from hydroquinone) which are p-phenylene, ar ³ Structural units being m-phenylene (structural units derived from isophthalic acid) or Ar ³ Is a structural unit of 4,4 '-biphenylene (structural unit derived from 4,4' -dihydroxybiphenyl).

Among them, the liquid crystal polymer preferably contains at least 1 selected from the group consisting of structural units derived from p-hydroxybenzoic acid and structural units derived from 6-hydroxy-2-naphthoic acid. And, the liquid crystal polymer preferably contains at least 1 selected from the group consisting of a structural unit derived from 6-hydroxy-2-naphthoic acid, a structural unit derived from an aromatic diol compound, a structural unit derived from terephthalic acid, and a structural unit derived from naphthalene dicarboxylic acid.

The content of the structural units derived from the aromatic hydroxycarboxylic acid is preferably 30 mol% or more, more preferably 30 mol% to 80 mol%, still more preferably 30 mol% to 60 mol%, and particularly preferably 30 mol% to 40 mol%, based on the total amount of all the structural units (the mass of each structural unit constituting the liquid crystal polymer is divided by the formula weight of each structural unit to obtain the equivalent (mol) of each structural unit and these are added together).

The content of the structural unit derived from the aromatic dicarboxylic acid is preferably 35 mol% or less, more preferably 10 mol% to 35 mol%, further preferably 20 mol% to 35 mol%, and particularly preferably 30 mol% to 35 mol% based on the total amount of all the structural units.

The content of the structural unit derived from the aromatic diol is preferably 35 mol% or less, more preferably 10 mol% to 35 mol%, further preferably 20 mol% to 35 mol%, and particularly preferably 30 mol% to 35 mol% based on the total amount of all the structural units.

The more the content of the structural unit derived from the aromatic hydroxycarboxylic acid is, the more easily the heat resistance, strength and rigidity are improved, but if it is too much, the solubility in a solvent is easily lowered.

The ratio of the content of the structural unit derived from the aromatic dicarboxylic acid to the content of the structural unit derived from the aromatic diol is represented by [ the content of the structural unit derived from the aromatic dicarboxylic acid ]/[ the content of the structural unit derived from the aromatic diol ] (mol/mol), and is preferably 0.9/1 to 1/0.9, more preferably 0.95/1 to 1/0.95, still more preferably 0.98/1 to 1/0.98.

The liquid crystal polymer may have 2 or more structural units derived from an aromatic hydroxycarboxylic acid, a structural unit derived from an aromatic dicarboxylic acid, and a structural unit derived from an aromatic diol, independently. The liquid crystal polymer may have structural units other than the above structural units, but the content thereof is preferably 10 mol% or less, more preferably 5 mol% or less, based on the total amount of all the structural units.

The liquid crystal polymer is preferably produced by melt-polymerizing a raw material monomer corresponding to a structural unit constituting the liquid crystal polymer. 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, tin (II) 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. Further, the melt polymerization may be further subjected to solid-phase polymerization as needed.

The liquid crystal polymer is preferably a liquid crystal polymer soluble in a specific organic solvent (hereinafter, also referred to as "soluble liquid crystal polymer").

Specifically, the soluble liquid crystal polymer in the present invention is preferably a liquid crystal polymer in which 0.1g or more of the liquid crystal polymer is dissolved in 100g of at least 1 solvent selected from the group consisting of N-methyl-2-pyrrolidone, N-dimethylacetamide, γ -butyrolactone, dimethylformamide, ethylene glycol monobutyl ether and ethylene glycol monoethyl ether at 25 ℃.

Melting point Tm-

The liquid crystal polymer is preferably a liquid crystal polymer that exhibits liquid crystallinity in a molten state. From the viewpoint of dielectric loss tangent and breaking strength, the melting point Tm of the liquid crystal polymer is preferably 280 ℃ or higher, more preferably 300 ℃ or higher, still more preferably 315 ℃ or higher, and particularly preferably 330 ℃ to 400 ℃.

The melting point Tm, also called flow temperature, is measured by capillary rheometry at 9.8MPa (100 kg/cm ² ) The temperature at which the liquid crystal polymer was melted while the temperature was raised at a rate of 4℃per minute and the polymer was extruded from a nozzle having an inner diameter of 1mm and a length of 10mm, and the viscosity of 4,800 Pa.s (48,000 poise) was a reference temperature for the molecular weight of the liquid crystal polymer (see "liquid crystal polymer-synthesis-molding-application-", CMC CORPORATION, 6/1987, 5/95).

Weight average molecular weight-

The weight average molecular weight of the liquid crystal polymer is preferably 13,000 or less, more preferably 3,000 to 13,000, further preferably 5,000 to 12,000, and particularly preferably 5,000 to 10,000. When the weight average molecular weight of the liquid crystal polymer is within the above range, the heat-treated film is excellent in heat conductivity, heat resistance, strength and rigidity in the thickness direction.

Dielectric loss tangent

From the viewpoints of dielectric loss tangent and adhesion to metal of the liquid crystal polymer film, the dielectric loss tangent of the liquid crystal polymer is preferably 0.005 or less, more preferably 0.004 or less, still more preferably 0.0035 or less, and particularly preferably more than 0 and 0.003 or less.

The method for measuring dielectric loss tangent in the present invention is measured by the following method.

The dielectric loss tangent was measured by a resonance perturbation method at a frequency of 10 GHz. A10 GHz cavity resonator (Kanto Flectronics Application & Development Inc. CP 531) was connected to a network analyzer (Agilent Technology Co., ltd. "E8363B"), a sample (width: 2.0 mm. Times. Length: 80 mm) of a liquid crystal polymer or a liquid crystal polymer film was inserted into the cavity resonator, and the dielectric loss tangent of the liquid crystal polymer or the liquid crystal polymer film was measured from the change in resonance frequency before and after insertion for 96 hours under an atmosphere of a temperature of 25℃and a humidity of 60% RH.

The liquid crystal polymer film may contain only 1 liquid crystal polymer or may contain 2 or more kinds.

The content of the liquid crystal polymer in the liquid crystal polymer layer is preferably 50 mass% or more, more preferably 70 mass% or more, and even more preferably 90 mass% or more, relative to the total mass of the liquid crystal polymer film, from the viewpoints of dielectric loss tangent and adhesion to metal of the liquid crystal polymer film. The upper limit of the content of the liquid crystal polymer is not particularly limited, and may be 100 mass%. That is, the liquid crystal polymer layer may be a layer composed of a liquid crystal polymer.

The liquid crystal polymer layer may contain other additives than liquid crystal polymers.

As the other additive, a known additive can be used. Specifically, for example, leveling agents, antifoaming agents, antioxidants, ultraviolet absorbers, flame retardants, colorants, fillers, and the like can be cited.

Further, the liquid crystal polymer layer may contain other resins than the liquid crystal polymer as other additives.

Examples of the other resins include: thermoplastic resins such as polypropylene, polyamide, polyester, polyphenylene sulfide, polyether ketone, polycarbonate, polyether sulfone, polyphenylene oxide, modified products thereof, and polyether imide; an elastomer such as a copolymer of glycidyl methacrylate and polyethylene; thermosetting resins such as phenolic resins, epoxy resins, polyimide resins, and cyanate resins.

The total content of the other additives in the liquid crystal polymer layer is preferably 25 parts by mass or less, more preferably 10 parts by mass or less, and further preferably 5 parts by mass or less, relative to 100 parts by mass of the content of the liquid crystal polymer. The liquid crystal polymer layer may not contain other additives.

The average thickness of the liquid crystal polymer layer is not particularly limited, but is preferably 5 μm to 90 μm, more preferably 10 μm to 70 μm, and particularly preferably 10 μm to 50 μm from the viewpoints of dielectric loss tangent and adhesion to metal of the liquid crystal polymer film.

The method for measuring the average thickness of each layer on the liquid crystal polymer film according to the present invention is as follows.

The liquid crystal polymer film was cut on a plane perpendicular to the plane direction of the liquid crystal polymer film, and the thickness was measured at 5 or more points of the cross section thereof, and the average value of these was taken as the average thickness.

< layer A >

The liquid crystal polymer film according to the present invention includes a layer a disposed on at least one surface of a liquid crystal polymer layer. The layer a may be disposed on only one surface of the liquid crystal polymer layer, or may be disposed on both surfaces of the liquid crystal polymer layer.

The material constituting the layer a is not particularly limited, and may be any of an organic material and an inorganic material, or both of them may be used. From the viewpoint of adhesion to metal, the layer a is preferably an adhesive layer containing an adhesive.

In the present invention, the kind of the adhesive is not particularly limited, and a known adhesive can be used.

The adhesive may preferably be a thermosetting resin.

Examples of the thermosetting resin include epoxy resin, phenolic resin, unsaturated imide resin, cyanate resin, isocyanate resin, benzoxazine resin, oxetane resin, amino resin, unsaturated polyester resin, allyl resin, dicyclopentadiene resin, silicone resin, triazine resin, and melamine resin. The thermosetting resin is not particularly limited to these, and a known thermosetting resin can be used. These thermosetting resins can be used singly or in combination of two or more.

As the adhesive, a commercially available adhesive containing a thermosetting resin can be used.

From the viewpoint of adhesion to metal, the adhesive preferably contains a compound having a functional group. The functional group is preferably at least 1 group selected from the group consisting of a group capable of covalent bonding, a group capable of ionic bonding, a group capable of hydrogen bonding, and a group capable of dipole-dipole interaction.

The number of functional groups in the compound having a functional group may be 1 or more, or may be 2 or more.

The compound having a functional group may have only 1 functional group or may have 2 or more functional groups.

The compound having a functional group may be a low-molecular compound or a high-molecular compound. From the viewpoint of adhesion to metal, the compound having a functional group is preferably a polymer compound.

The compound having a functional group is preferably a polymer having a weight average molecular weight of 1,000 or more, more preferably a polymer having a weight average molecular weight of 2,000 or more, still more preferably a polymer having a weight average molecular weight of 3,000 or more, and particularly preferably a polymer having a weight average molecular weight of 5,000 or more and 200,000 or less, from the viewpoint of adhesion to a metal.

Functional group

The functional group in the compound having a functional group is preferably at least 1 group selected from the group consisting of a group capable of covalent bonding, a group capable of ionic bonding, a group capable of hydrogen bonding, and a group capable of dipole-to-dipole interaction.

The functional group is preferably a group capable of covalent bonding from the viewpoint of adhesion to a metal.

Further, from the viewpoints of storage stability and handling properties, the functional group is preferably an ion-bondable group, a hydrogen-bondable group, or a group capable of undergoing dipole-dipole interaction.

Radicals capable of covalent bonding

The group capable of covalent bonding is not particularly limited as long as it is a group capable of forming a covalent bond, and examples thereof include an epoxy group, an oxetanyl group, an isocyanate group, an acid anhydride group, a carbodiimide group, an N-hydroxy ester group, an imide ester group, a haloalkyl group, a thiol group, a hydroxyl group, a carboxyl group, an amino group, an amido group, an isocyanate group, an aldehyde group, a sulfonic acid group, and the like. Among them, from the viewpoint of adhesion to metal, the group capable of covalent bonding is preferably at least 1 group selected from the group consisting of an epoxy group, an oxetane group, an isocyanate group, an acid anhydride group, a carbodiimide group, an N-hydroxy ester group, a glyoxal group, an imide ester group, a haloalkyl group, and a thiol group.

Further, as described below, the surface of the metal to be bonded preferably has a group paired with a functional group of the compound having a functional group.

As a combination of groups capable of covalent bonding (a combination of a functional group of a compound having a functional group and a group provided on a metal surface), specifically, for example, in the case where one is an epoxy group, the other may be a hydroxyl group, an amino group, or the like.

In addition, for example, when one is an N-hydroxy ester group or an imide ester group, the other may be an amino group or the like.

Groups capable of ionic bonding

Examples of the group capable of ionic bonding include a cationic group and an anionic group.

The cationic group is preferably an onium group. Examples of the onium group include an ammonium group, a pyridinium group, a phosphonium group, an oxonium group, a sulfonium group, a seleno group, and an iodonium group. Among them, from the viewpoint of adhesion to metals, an ammonium group, a pyridinium group, a phosphonium group or a sulfonium group is preferable, an ammonium group or a phosphonium group is more preferable, and an ammonium group is particularly preferable.

The anionic group is not particularly limited, and examples thereof include phenolsHydroxy, carboxy, -SO ₃ H、-OSO ₃ H、-PO ₃ H、-OPO ₃ H ₂ 、-CONHSO ₂ -、-SO ₂ NHSO ₂ -and the like. Among them, a phosphate group, a phosphonate group, a phosphinate group, a sulfate group, a sulfonate group, a sulfenate group or a carboxyl group is preferable, a phosphate group or a carboxyl group is more preferable, and a carboxyl group is still more preferable.

As a combination of groups capable of ionic bonding (a combination of a functional group of a compound having a functional group and a group which is present on a metal surface), specifically, for example, in the case where one has an acidic group, the other may be a base.

Examples of the acidic group include a carboxyl group, a sulfo group, and a phosphate group, and a carboxyl group is preferable.

In the case where one is a carboxyl group, examples of the group capable of being ionically bonded to the carboxyl group include a tertiary amino group, a pyridyl group, and a piperidyl group.

Hydrogen-bonding-enabling groups

Examples of the hydrogen-bonding-capable group include a group having a hydrogen bond supplying site and a group having a hydrogen bond receiving site.

The hydrogen bond supply site may have a structure having an active hydrogen atom capable of hydrogen bonding, and is preferably a structure represented by x—h.

X preferably represents a heteroatom, a nitrogen atom or an oxygen atom.

From the viewpoint of adhesion to metal, the hydrogen bond supply site is preferably at least 1 structure selected from the group consisting of a hydroxyl group, a carboxyl group, a primary amino group, a secondary amino group, an imide group, a urea bond, and a urethane bond, more preferably at least 1 structure selected from the group consisting of hydroxyl group, carboxyl group, primary amino group, secondary amino group, maleimide group, urea bond and urethane bond, still more preferably at least 1 structure selected from the group consisting of hydroxyl group, carboxyl group, primary amino group, secondary amino group and maleimide group, particularly preferably at least 1 structure selected from the group consisting of hydroxyl group and secondary amino group.

The hydrogen bond accepting site preferably includes a structure having an atom which does not share an electron pair, more preferably includes a structure having an oxygen atom which does not share an electron pair, still more preferably at least 1 structure selected from the group consisting of a carbonyl group (including carbonyl structures such as carboxyl groups, amido groups, imido groups, urea bonds, and urethane bonds) and a sulfonyl group (including sulfonyl structures such as sulfonylamino groups), and particularly preferably a carbonyl group (including carbonyl structures such as carboxyl groups, amido groups, imido groups, urea bonds, and urethane bonds).

The group capable of hydrogen bonding is preferably a group having both the hydrogen bond supplying site and the hydrogen bond receiving site, preferably a group having a carboxyl group, an amido group, an imido group, a urea bond, a urethane bond or a sulfonylamino group, more preferably a group having a carboxyl group, an amido group, an imido group or a sulfonylamino group.

As a combination of groups capable of hydrogen bonding (a combination of a functional group of a compound having a functional group and a group having a metal surface), specifically, in the case where one group includes a group having a hydrogen bond supplying site, the other group may include a group having a hydrogen bond receiving site.

For example, when one is a carboxyl group, the other is an amido group, a carboxyl group, or the like.

In addition, for example, when one is a phenolic hydroxyl group, the other is a phenolic hydroxyl group or the like.

Radicals capable of dipole-dipole interactions

The group capable of performing dipole-dipole interaction may be a group having a polarized structure other than the structure represented by x—h (X represents a heteroatom, a nitrogen atom or an oxygen atom) among the above-described groups capable of hydrogen bonding, and an atom bonded with a different electronegativity is preferable.

The combination of atoms having different electronegativity is preferably a combination of at least 1 atom selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom and a carbon atom, and more preferably a combination of at least 1 atom selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom and a carbon atom.

Among them, from the viewpoint of adhesion to a metal, a combination of a nitrogen atom and a carbon atom, and a combination of a carbon atom and a nitrogen atom, an oxygen atom, and a sulfur atom are preferable, and specifically, cyano groups, melamine groups, and sulfonic acid amide groups are more preferable.

As the combination of groups capable of dipole-to-dipole interaction (combination of a functional group of a compound having a functional group and a group provided on a metal surface), the same combination of groups capable of dipole-to-dipole interaction is preferable.

For example, when one is a cyano group, the other is a cyano group.

In addition, for example, in the case where one is a sulfonamido group, the other may be a sulfonamido group.

Specific examples of the bonding or interaction of 2 kinds of functional groups are shown below, and the bonding or interaction in the present invention is not limited thereto.

[ chemical formula 1]

Covalent bonding

Ion bonding

Interaction between dipoles

From the viewpoint of adhesion to metal, the compound having a functional group is preferably a polyfunctional epoxy compound or a polymer of a polyfunctional epoxy compound, more preferably a 2-functional epoxy compound or a polymer of a 2-functional epoxy compound, and particularly preferably a polymer of a 2-functional epoxy compound.

The adhesive layer may contain only 1 kind of adhesive, or may contain 2 or more kinds of adhesives.

The content of the adhesive in the adhesive layer is preferably 50 mass% or more, more preferably 80 mass% or more, and even more preferably 90 mass% or more, relative to the total mass of the liquid crystal polymer film, from the viewpoint of adhesion to metal. The upper limit of the content of the binder is not particularly limited, and may be 100 mass%. That is, the adhesive layer may be a layer made of an adhesive.

The adhesive layer may contain other additives than the adhesive.

The average thickness of the layer a is not particularly limited, but is preferably 5 μm to 90 μm, more preferably 10 μm to 70 μm, and particularly preferably 15 μm to 30 μm from the viewpoint of adhesion to metal.

< mixing region >

In the liquid crystal polymer film according to the present invention, a mixed region including the liquid crystal polymer and the material constituting the layer a is formed between the liquid crystal polymer layer and the layer a.

Details of the liquid crystal polymer and the materials constituting the layer a included in the mixed region are described in the column of the liquid crystal polymer layer and the layer a.

Since the above-described mixed region is formed, the liquid crystal polymer film according to the present invention has excellent adhesion to a layer formed on the liquid crystal polymer film.

Whether or not a mixed region is formed in the liquid crystal polymer film can be confirmed by the following method. The liquid crystal polymer film was cut in an oblique direction, and the obtained cross-sectional sample was evaluated by TOF-SIMS (time-of-flight secondary ion mass spectrometry), and the portion where the fragment derived from the liquid crystal polymer layer and the fragment derived from layer A were observed at the same time was judged as a mixed region. The presence of the fragment is determined to be equal to or higher than the detection limit.

The average thickness of the mixed region is preferably 1nm to 10. Mu.m, more preferably 100nm to 5. Mu.m, and even more preferably 300nm to 2. Mu.m, from the viewpoint of adhesion to metal.

The average thickness of the liquid crystal polymer film according to the present invention is preferably 6 μm to 200 μm, more preferably 12 μm to 100 μm, and particularly preferably 20 μm to 60 μm from the viewpoints of strength, dielectric loss tangent of the polymer film, and adhesion to metal.

The average thickness of the liquid crystal polymer film is measured at any 5 points by an adhesive film thickness meter, for example, an electronic micrometer (product name "KG3001A", manufactured by ANRITSU CORPORATI N), and the average value of these is used.

From the viewpoint of dielectric constant, the dielectric loss tangent of the liquid crystal polymer film according to the present invention is preferably 0.005 or less, more preferably more than 0 and 0.003 or less.

< method for producing liquid Crystal Polymer film >

The method for producing the liquid crystal polymer film according to the present invention is not particularly limited, and a known method can be referred to.

The method for producing a liquid crystal polymer film according to the present invention comprises: for example, a step of forming a liquid crystal polymer-containing material into a film (hereinafter, also referred to as a film forming step), a step of applying a liquid (for example, an adhesive composition) containing a material constituting the layer a onto the formed film (hereinafter, also referred to as a coating step), a step of stretching the film coated with the liquid containing the material constituting the layer a (hereinafter, also referred to as a stretching step), and a step of annealing the stretched film (hereinafter, also referred to as an annealing step).

By providing the coating step after the film formation step and before the stretching treatment, a liquid crystal polymer film in which a mixed region including a liquid crystal polymer and a material constituting the layer a is formed between the liquid crystal polymer layer and the layer a can be obtained.

As a film forming method in the film forming step, for example, a casting method, a coating method, an extrusion method, or the like is preferably used. Among them, the film forming method is preferably a casting method.

Examples of the solvent 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; amide compounds such as N, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone, and urea compounds such as tetramethylurea; nitro compounds such as nitromethane and nitrobenzene; sulfur compounds such as dimethyl sulfoxide and sulfolane; phosphorus compounds such as hexamethylphosphoric acid amide and tri-n-butyl phosphate, etc., and 2 or more of them may be used.

The solvent is preferably a solvent containing an aprotic compound (particularly an aprotic compound having no halogen atom) as a main component, and the proportion of the aprotic compound in the solvent as a whole is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and particularly preferably 90 to 100% by mass, from the viewpoint of low corrosiveness and easiness in handling. In addition, as the aprotic compound, from the viewpoint of easy dissolution of the liquid crystal polymer, 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 solvent, a solvent containing a compound having a dipole moment of 3 to 5 as a main component is preferable from the viewpoint of easy dissolution of the liquid crystal polymer, and the proportion of the compound having a dipole moment of 3 to 5 in the solvent as a whole is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and particularly preferably 90 to 100% by mass.

As the aprotic compound, a compound having a dipole moment of 3 to 5 is preferably used.

The solvent is preferably a solvent containing a compound having a boiling point of 220 ℃ or less at 1 atmosphere as a main component, and the proportion of the compound having a boiling point of 220 ℃ or less at 1 atmosphere in the entire solvent is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and particularly preferably 90 to 100% by mass, from the viewpoint of easy removal.

As the aprotic compound, a compound having a boiling point of 220℃or less under 1 atmosphere is preferably used.

In the case of forming a film by the above-mentioned casting method, coating method, extrusion method, or the like, a support may be used. In the case where a metal layer (metal foil) or the like used in a laminate to be described later is used as a support, the laminate may be used as it is without peeling.

Examples of the support include a glass plate, a resin film, and a metal foil. Among them, the resin film is preferable, and particularly, a Polyimide (PI) film is preferable in terms of excellent heat resistance, easiness of application of the composition, and easiness of peeling from the liquid crystal polymer.

Examples of commercially available Polyimide (PI) films include Ube [ industries, ltd., UPILEX S and UPILEX R, DU PONT-TORAY C0., LTD., kapton, SKC KOLONP [ manufactured by Co., ltd., IF30, IF70, LV300, etc.

The support is preferably formed with a surface treatment layer on the surface thereof to facilitate peeling. The surface treatment layer preferably contains a fluororesin.

The average thickness of the support is not particularly limited, but is preferably 25 μm or more and 75 μm or less, more preferably 50 μm or more and 75 μm or less.

Further, as a method for removing at least a part of the solvent from the cast or coated film-like composition (cast film or coating film), there is no particular limitation, and a known drying method can be used.

The coating step, the stretching step, and the annealing step are not particularly limited, and generally known methods can be used.

Use(s)

The liquid crystal polymer film according to the present invention can be used for various applications. Among them, the film is suitable for films for electronic components such as printed wiring boards, and is more suitable for flexible printed circuit boards.

The liquid crystal polymer film according to the present invention can be suitably used as a liquid crystal polymer film for metal adhesion.

[ laminate ]

The laminate according to the present invention may be a laminate comprising the liquid crystal polymer film according to the present invention. The liquid crystal polymer film according to the present invention has excellent adhesion to a layer formed on the liquid crystal polymer film. Accordingly, the laminate according to the present invention preferably includes the liquid crystal polymer film according to the present invention and a layer disposed on at least one surface of the liquid crystal polymer film. The layer disposed on at least one surface of the liquid crystal polymer film is not particularly limited, and examples thereof include a polymer layer and a metal layer. The layer disposed on at least one side of the liquid crystal polymer film may be a coating layer.

The layer disposed on at least one surface of the liquid crystal polymer film may be disposed on the entire surface of the liquid crystal polymer film or may be disposed only on a part of the liquid crystal polymer film.

The laminate according to the present invention preferably includes the liquid crystal polymer film according to the present invention and a metal layer or a metal wiring disposed on at least one surface of the liquid crystal polymer film. In particular, the metal layer or the metal wiring is preferably disposed on the layer a (e.g., adhesive layer) side of the liquid crystal polymer film.

The metal layer or metal wiring may be a known metal layer or metal wiring, and is preferably a copper layer or copper wiring, for example.

The method for bonding the liquid crystal polymer film and the metal layer according to the present invention is not particularly limited, and a known lamination method can be used.

The peel strength between the liquid crystal polymer film and the metal layer is preferably 0.5kN/m or more, more preferably 0.7kN/m or more, still more preferably 0.7kN/m to 2.0kN/m, and particularly preferably 0.9kN/m to 1.5kN/m.

In the present invention, the peel strength between the liquid crystal polymer film and the metal layer (e.g., copper layer) is measured by the following method.

A test piece for peeling was prepared from a laminate of a liquid crystal polymer film and a metal layer, the polymer film was fixed to a flat plate with a double-sided adhesive tape, and the strength (kN/m) at which the polymer film was peeled from the metal layer at a speed of 50 mm/min was measured by a 180℃method in accordance with JIS C5016 (1994).

The metal layer is preferably a copper layer. The copper layer is preferably a rolled copper foil formed by a rolling method or an electrolytic copper foil formed by an electrolytic method, and more preferably a rolled copper foil from the viewpoint of flex resistance.

The average thickness of the metal layer (preferably copper layer) is not particularly limited, but is preferably 3 μm to 30 μm, more preferably 5 μm to 20 μm. The copper foil may be a carrier-bearing copper foil that is formed on a support (carrier) in a peelable manner. As the carrier, a known carrier can be used. The average thickness of the carriers is not particularly limited, but is preferably 10 μm to 100 μm, more preferably 18 μm to 50 μm.

In view of adhesion to the liquid crystal polymer film, the metal layer or the metal wiring preferably has a group capable of interacting with the liquid crystal polymer film on a side surface thereof in contact with the liquid crystal polymer film. In the case where the adhesive contains a compound having a functional group, the group capable of interacting is preferably a group corresponding to a functional group of the compound having a functional group, such as an amino group, an epoxy group, a hydroxyl group, or an epoxy group.

Examples of the group capable of interaction include a group as a functional group in the above-mentioned compound having a functional group.

Among them, the group capable of interacting is preferably a group capable of covalent bonding, more preferably an amino group or a hydroxyl group, and particularly preferably an amino group, from the viewpoints of adhesion and handling easiness.

For example, the metal layer in the laminate according to the present invention is processed into a desired circuit pattern by etching, and it is also preferable to manufacture a flexible printed circuit board. The etching method is not particularly limited, and a known etching method can be used.

[ Polymer film ]

The polymer film according to the present invention comprises: a polymer layer containing at least 1 polymer selected from the group consisting of a fluorine-based polymer, a polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond, a polyphenylene ether, and an aromatic polyether ketone; and a layer A disposed on at least one surface of the polymer layer, wherein a mixed region including the polymer and a material constituting the layer A is formed between the polymer layer and the layer A.

< Polymer layer >

In the polymer film according to the present invention, the polymer layer contains at least 1 polymer selected from the group consisting of a fluorine-based polymer, a polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond, a polyphenylene ether, and an aromatic polyether ketone.

Fluorine-based polymer

Examples of the fluorine-based polymer include polytetrafluoroethylene, chlorotrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, perfluoroalkoxy fluororesin, tetrafluoroethylene/hexafluoropropylene copolymer, ethylene/tetrafluoroethylene copolymer, and ethylene/chlorotrifluoroethylene copolymer.

Among them, polytetrafluoroethylene is preferable.

Further, the fluorine-based polymer may be a homopolymer or copolymer comprising a fluorinated alpha-olefin monomer (i.e., an alpha-olefin monomer having at least 1 fluorine atom) and (if necessary) structural units derived from a non-fluoroethylenically unsaturated monomer reactive with the fluorinated alpha-olefin monomer.

As the fluorinated alpha-olefin monomer, CF may be mentioned ₂ ＝CF ₂ 、CHF＝CF ₂ 、CH ₂ ＝CF ₂ 、CHCl＝CHF、CClF＝CF ₂ 、CCl ₂ ＝CF ₂ 、CClF＝CClF、CHF＝CCl ₂ 、CH ₂ ＝CClF、CCl ₂ ＝CClF、CF ₃ CF＝CF ₂ 、CF ₃ CF＝CHF、CF ₃ CH＝CF ₂ 、CF ₃ CH＝CH ₂ 、CHF ₂ CH＝CHF、CF ₃ CF＝CF ₂ Perfluoro (alkyl group having 2 to 8 carbon atoms) vinyl ether (e.g., perfluoromethyl vinyl ether, perfluoropropyl vinyl ether, perfluorooctyl vinyl ether), etc. Of these, a material selected from tetrafluoroethylene (CF ₂ ＝CF ₂ ) Chlorotrifluoroethylene (ccif=cf) ₂ ) (perfluorobutyl) ethylene, polyvinylidene fluoride (CH) ₂ ＝CF ₂ ) Hexafluoropropylene (CF) ₂ ＝CFCF ₃ ) At least 1 monomer in the group consisting of.

Examples of the non-fluorinated monoethylenically unsaturated monomer include ethylene, propylene, butene, and an ethylenically unsaturated aromatic monomer (for example, styrene and α -methylstyrene).

The fluorinated alpha-olefin monomer may be used alone or in combination of 1 or more than 2.

The non-fluoroethylenically unsaturated monomer may be used alone or in combination of 1 or more than 2.

Examples of the fluorine-based polymer include Polychlorotrifluoroethylene (PCTFE), poly (chlorotrifluoroethylene-propylene), poly (ethylene-tetrafluoroethylene) (ETFE), poly (ethylene-chlorotrifluoroethylene) (ECTFE), poly (hexafluoropropylene), poly (tetrafluoroethylene) (PTFE), poly (tetrafluoroethylene-ethylene-propylene), poly (tetrafluoroethylene-hexafluoropropylene) (FEP), poly (tetrafluoroethylene-propylene) (FEPM), poly (tetrafluoroethylene-perfluoropropylene vinyl ether), poly (tetrafluoroethylene-perfluoroalkyl vinyl ether) (PFA) (e.g., poly (tetrafluoroethylene-perfluoropropyl vinyl ether)), polyethylene fluoride (PVF), polyvinylidene fluoride (PVDF), poly (vinylidene fluoride-chlorotrifluoroethylene), perfluoropolyether, perfluorosulfonic acid, and perfluoropolyoxetane.

The fluorine-based polymer may be used alone or in combination of 1 or more than 2.

The fluorine-based polymer is preferably at least 1 of FEP, PFA, ETFE or PTFE. FEP is available from DuPont under the trade name TEFLON (registered trademark) FEP or daidin INDUSTRIES, LTD. under the trade name neolon FEP; PFA is available from DAIKININDUSTRIES, LTD. under the trade name NEOFLON PFA available from DuPont under the trade name TEFLON (registered trademark) PFA, or from Solvay Solexis under the trade name HYFLON PFA.

The fluoropolymer preferably comprises PTFE. The PTFE can comprise a PTFE homopolymer, a partially modified PTFE homopolymer, or a combination comprising one or both of them. The partially modified PTFE homopolymer preferably contains less than 1 mass% of structural units derived from a comonomer other than tetrafluoroethylene, based on the total mass of the polymer.

The fluorine-based polymer may be a crosslinkable fluorine polymer having a crosslinkable group. The crosslinkable fluoropolymer can be crosslinked by a conventionally known crosslinking method. One of the representative crosslinkable fluoropolymers is a fluoropolymer having (meth) acryloyloxy groups. For example, the crosslinkable fluoropolymer may be represented by the following formula:

H ₂ C＝CR’COO-(CH ₂ ) _n -R-(CH ₂ ) _n -OOCR’＝CH ₂

wherein R is a fluorine-based oligomer chain having 2 or more structural units derived from a fluorinated alpha-olefin monomer or a non-fluorinated monoethylenically unsaturated monomer, and R' is H or-CH ₃ N is 1 to 4.R may be a fluorine-based oligomer chain including a structural unit derived from tetrafluoroethylene.

Since the radical crosslinking reaction is started by the (meth) acryloyloxy group on the fluorine-based polymer, a crosslinked fluoropolymer network structure can be formed by exposing the fluorine-based polymer having the (meth) acryloyloxy group to a radical source. The radical source is not particularly limited, and a photo radical polymerization initiator or an organic peroxide is preferably used. Suitable photo-radical polymerization initiators and organic peroxides are well known in the art. The crosslinkable fluoropolymer is commercially available, and for example, VITON B manufactured by DuPont corporation may be mentioned.

Polymers comprising structural units derived from compounds having a cyclic aliphatic hydrocarbon group and a group having an ethylenic unsaturation

Examples of the polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond include thermoplastic resins having a structural unit formed from a monomer such as norbornene or a polycyclic norbornene monomer and formed from a cyclic olefin, and also referred to as thermoplastic cyclic olefin resins.

The polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond may be a ring-opened polymer of the above cyclic olefin or a hydrogenated product of a ring-opened copolymer using 2 or more kinds of cyclic olefins, or may be an addition polymer of a cyclic olefin and an aromatic compound having an ethylenically unsaturated bond such as a chain olefin or a vinyl group. Further, a polar group may be introduced into a polymer including a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond.

The polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond may be used alone or in combination of 1 or more than 2.

The cyclic aliphatic hydrocarbon group may have a single ring structure, may have a condensed ring obtained by condensing 2 or more rings, or may have a bridged ring.

Examples of the ring structure of the cyclic aliphatic hydrocarbon group include a cyclopentane ring, a cyclohexane ring, a cyclooctane ring, an isophorone ring, a norbornane ring, and a dicyclopentane ring.

The compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond may be a monofunctional ethylenically unsaturated compound or a polyfunctional ethylenically unsaturated compound.

The number of the cyclic aliphatic hydrocarbon groups in the compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond may be 1 or more, or may be 2 or more.

The polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond may be a polymer obtained by polymerizing at least 1 compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond, and may be a polymer obtained by polymerizing 2 or more compounds having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond, or may be a copolymer with another ethylenically unsaturated compound having no cyclic aliphatic hydrocarbon group.

Also, the polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond is preferably a cyclic olefin polymer.

Polyphenylene ether-

In the case of heat curing after film formation, the weight average molecular weight (Mw) of the polyphenylene ether is preferably 500 to 5,000, more preferably 500 to 3,000, from the viewpoints of heat resistance and film formability. Further, the heat curing is not particularly limited, but is preferably 3,000 ～ 100,000, and more preferably 5,000 to 50,000.

The polyphenylene ether preferably has an average number of phenolic hydroxyl groups at the molecular terminals (terminal hydroxyl groups) per 1 molecule of 1 to 5, more preferably 1.5 to 3, from the viewpoints of dielectric loss tangent and heat resistance.

The hydroxyl number or phenolic hydroxyl group of a polyphenylene ether is known, for example, from the standard value of the product of the polyphenylene ether. Examples of the terminal hydroxyl group number or the terminal phenolic hydroxyl group number include a value indicating an average value of hydroxyl groups or phenolic hydroxyl groups per 1 molecule of all polyphenylene ethers present in 1 mole of polyphenylene ether.

The polyphenylene ether may be used alone or in combination of 1 or more than 2.

Examples of the polyphenylene ether include polyphenylene ether composed of at least one of 2, 6-xylenol, 2-functional phenol and 3-functional phenol, and poly (2, 6-dimethyl-1, 4-phenylene ether) and the like containing polyphenylene ether as a main component. More specifically, for example, a compound having a structure represented by the formula (PPE) is preferable.

[ chemical formula 2]

In the formula (PPE), X represents an alkylene group having 1 to 3 carbon atoms or a single bond, m represents an integer of 0 to 20, n represents an integer of 0 to 20, and the sum of m and n represents an integer of 1 to 30.

Examples of the alkylene group in X include a dimethylmethylene group and the like.

Aromatic polyether ketone

The aromatic polyether ketone is not particularly limited, and known aromatic polyether ketones can be used.

The aromatic polyetherketone is preferably polyetheretherketone.

Polyether-ether-ketone is 1 kind of aromatic polyether-ketone, and is a polymer with bonds such as ether bond, carbonyl bond (ketone) and the like sequentially. The bonds are preferably linked by a 2-valent aromatic group.

The aromatic polyether ketone may be used alone or in combination of 1 or more than 2.

Examples of the aromatic polyether ketone include polyether ether ketone (PEEK) having a chemical structure represented by the following formula (P1), polyether ketone (PEK) having a chemical structure represented by the following formula (P2), polyether ketone (PEKK) having a chemical structure represented by the following formula (P3), polyether ether ketone (PEEKK) having a chemical structure represented by the following formula (P4), and polyether ketone (PEKK) having a chemical structure represented by the following formula (P5).

[ chemical formula 3]

From the viewpoint of mechanical properties, each n of the formulas (P1) to (P5) is preferably 10 or more, more preferably 20 or more. On the other hand, n is preferably 5,000 or less, more preferably 1,000 or less, from the viewpoint of easy production of the aromatic polyether ketone. That is, n is preferably 10 to 5,000, more preferably 20 to 1,000.

< layer A >

The polymer film according to the present invention includes a layer a disposed on at least one surface of a polymer layer. The layer a may be disposed on only one side of the polymer layer or may be disposed on both sides of the liquid crystal polymer layer. The preferred manner of layer a is the same as that of layer a on the liquid crystal polymer film described above.

< mixing region >

In the polymer film according to the present invention, a mixed region including a polymer and a material constituting layer a is formed between the polymer layer and layer a.

The details of the polymer and the materials constituting the layer a contained in the mixed region are described in the column of the polymer layer and the layer a.

Since the above-described mixed region is formed, the polymer film according to the present invention has excellent adhesion to a layer formed on the polymer film.

Whether or not the mixed region is formed in the polymer film can be confirmed by the same method as the mixed region on the liquid crystal polymer film.

The average thickness of the polymer film according to the present invention is preferably 6 μm to 200 μm, more preferably 12 μm to 100 μm, and particularly preferably 20 μm to 60 μm from the viewpoints of strength, dielectric loss tangent of the polymer film, and adhesion to metal.

From the viewpoint of the dielectric constant, the dielectric loss tangent of the polymer film according to the present invention is preferably 0.005 or less, more preferably more than 0 and 0.003 or less.

The polymer film according to the present invention can be formed as a laminate in the same manner as the liquid crystal polymer film.

Examples

The present invention will be described in further detail with reference to examples. The materials, amounts used, ratios, treatment contents, treatment order, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Accordingly, the scope of the present invention is not limited to the specific examples shown below.

Assay

[ dielectric loss tangent ]

Dielectric loss tangent was measured by a resonance perturbation method at a frequency of 10 GHz. A10 GHz cavity resonator (CP 531 of Kanto Electronics Application & Development Inc.) was connected to a network analyzer (manufactured by Agilent Technology Co., ltd. "E8363B"), a film sample (width: 2.0 mm. Times. Length: 80 mm) was inserted into the cavity resonator, and the dielectric loss tangent of the film was measured from the change in resonance frequency before and after insertion for 96 hours under an atmosphere of a temperature of 25℃and a humidity of 60% RH.

[ peel Strength ]

A test piece for peeling 1.0cm in width was prepared from a laminate of a liquid crystal polymer film and a copper layer, and the liquid crystal polymer film was fixed to a flat plate with a double-sided adhesive tape, and the strength (kN/m) at which the copper layer was peeled from the liquid crystal polymer film at a speed of 50 mm/min was measured by a 180℃method in accordance with JIS C5016 (1994).

Production example

< liquid Crystal Polymer >

LC-A: a liquid crystal polymer produced by the following production method

LC-B: a liquid crystal polymer produced by the following production method

LC-A production

Into a reactor equipped with a stirrer, a torque meter, a nitrogen inlet tube, a thermometer and a reflux cooler, 940.9g (5.0 mol) of 6-hydroxy-2-naphthoic acid, 377.9g (2.5 mol) of 4-hydroxyacetoacetamol, 415.3g (2.5 mol) of isophthalic acid and 867.8g (8.4 mol) of acetic anhydride were placed, and after replacing the gas in the reactor with nitrogen, the temperature was raised from room temperature (23 ℃) to 140℃over 60 minutes under stirring under a nitrogen gas stream, and refluxed at 140℃for 3 hours.

Then, while distilling off acetic acid and unreacted acetic anhydride as by-products, the temperature was raised from 150℃to 300℃over 5 hours, and after holding at 300℃for 30 minutes, 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-crystalline polyester (B1). The flow initiation temperature of the liquid-crystalline polyester (B1) was 193.3 ℃.

The liquid-crystalline polyester (B1) obtained above was heated from room temperature to 160 ℃ over 2 hours and 20 minutes under nitrogen atmosphere, then heated from 160 ℃ to 180 ℃ over 3 hours and 20 minutes, and kept at 180 ℃ for 5 hours, whereby it was subjected to solid-phase polymerization, then cooled, and then pulverized with 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 from room temperature (23 ℃) to 180℃over 1 hour and 25 minutes, then heated from 180℃to 255℃over 6 hours and 40 minutes, and kept at 255℃for 5 hours under se:Sub>A nitrogen atmosphere, whereby it was subjected to solid-phase polymerization and then cooled to obtain se:Sub>A powdery liquid crystalline polyester (LC-A). The flow initiation temperature of the liquid crystalline polyester (LC-A) was 302 ℃. The melting point of the liquid crystal polyester (LC-A) was measured by se:Sub>A differential scanning calorimeter and found to be 311 ℃.

LC-B production

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 placed in a reactor equipped with a stirrer, a torque meter, a nitrogen inlet pipe, a thermometer and a reflux cooler. After the gas in the reactor was replaced with nitrogen, the temperature was raised from room temperature to 145℃over 15 minutes while stirring under a nitrogen stream, and the mixture was 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℃to 310℃over 3 hours and 30 minutes, and after holding at 310℃for 3 hours, the solid liquid crystal polyester (LC-B) was taken out, and the liquid crystal polyester (LC-B) was cooled to room temperature. The flow initiation temperature of the polyester (LC-B) was 265 ℃.

< Polymer >

P-1：

A commercially available aqueous dispersion of Polytetrafluoroethylene (PTFE) particles (PolyFLON PTFE D-711, average particle diameter 0.30 μm, solid content 60%, DAIKIN INDUSTRIES, LTD.) was used in the amounts shown in Table 1.

< additive >

F-1: commercially available low dielectric loss tangent filler (specially treated fused spherical silica, manufactured by Denka company Lim North ed) having an average particle diameter of 600nm

< composition for adhesive layer >

M-1: commercially available low dielectric adhesive (varnish of SLK (Shin-Etsu Chemical Co., ltd.) mainly comprising a polymer type curable compound)

M-2: commercially available low dielectric adhesive (thermoplastic polyimide varnish PIAD 100H,ARAKAWA CHEMICAL INDUSTRIES,LTD)

(examples 1 to 3 and examples 5 to 8)

In examples 1 to 3 and examples 5 to 8, films were formed by a casting method (solution film forming method).

Preparation of liquid Crystal Polymer solutions

In examples 1 to 3 and examples 6 to 8, the above liquid crystal polymer was added to N-methylpyrrolidone, and stirred at 140 ℃ for 4 hours under a nitrogen atmosphere, thereby obtaining a liquid crystal polymer solution. The solid content concentration was set to 8 mass%.

In example 5, the above liquid crystal polymer and the above additive were added to N-methylpyrrolidone, and stirred at 140 ℃ for 4 hours under a nitrogen atmosphere, thereby obtaining a liquid crystal polymer solution. The content of the additive added to the liquid crystal polymer layer was the amount shown in table 1. The solid content concentration was set to 11 mass%.

Next, the above solution was passed through a sintered fiber metal filter having a nominal pore size of 10 μm, and then further passed through a sintered fiber metal filter having a nominal pore size of 10 μm, whereby a liquid crystal polymer solution was obtained.

Film forming process

The obtained liquid crystal polymer solution was fed into a casting die, and was cast on a stainless steel belt (support). At the time point when the amount of the residual solvent became 25 mass%, the film was obtained by peeling from the support and conveying the web (web) while applying a stretching force (draw) of 10%.

Formation of the adhesive layer 1-

The adhesive layer 1 was formed by applying the adhesive layer composition described in table 1 to the obtained film until the thickness of the adhesive layer became 1/10 of the thickness described in table 1 and drying the same.

Stretching and annealing

The film with the adhesive layer 1 formed was held by a tenter and stretched by 15% in the transverse direction. Thereafter, a heat treatment was performed under a nitrogen atmosphere at 1 ℃ per minute to raise the temperature from room temperature to 270 ℃ and maintained at that temperature for 2 hours.

Formation of an adhesive layer 2-

The composition for an adhesive layer described in table 1 was further applied onto the adhesive layer 1 until the thickness of the adhesive layer became the thickness described in table 1, and dried, thereby obtaining a liquid crystal polymer film.

Next, using the obtained liquid crystal polymer film, a copper-clad laminate was produced. The preparation method is as follows.

Copper clad laminate precursor procedure

Copper foil (Fukuda Metal Foil & Powder Co., ltd., CF-T9DA-SV-18, thickness 18 μm, surface roughness Rz of the adhesion surface (treated surface) was 0.85 μm) was placed in contact with the surface of the liquid crystal polymer film on which the adhesive layer was formed, and a lamination treatment was performed for 1 minute using a laminator (Nikko-Materials Co., ltd., vacuum laminator V-130) at 140℃and a lamination pressure of 0.4MPa, whereby a copper foil laminated plate precursor was obtained.

Formally hot-press bonding process

The obtained copper-clad laminate precursor was subjected to thermocompression bonding at 300℃and 4.5MPa for 10 minutes using a thermocompressor (Toyo Seiki Seisaku-sho, ltd. Times "MP-SNL"), thereby producing a copper-clad laminate.

Example 4

In example 4, a film was formed by an extrusion method (melt film forming method).

Preparation of resin particles

The liquid crystal polymer was dried in a nitrogen flow environment at 80℃and then pelletized in a nitrogen atmosphere by a twin-screw extruder. The lipid particles obtained were used after drying in dry air at 80 ℃.

Film forming process

The obtained pellets were fed into a cylinder from the same feed port of a twin-screw extruder having a screw diameter of 50mm, and heated and kneaded at 340 to 350℃to obtain a kneaded product. Next, the kneaded material was fed into a T die, and the film-like kneaded material in a molten state was discharged, and was collected and solidified by a cooling roll while applying a stretching force of 10%.

Formation of the adhesive layer 1-

The adhesive layer 1 was formed by applying the adhesive layer composition M-1 to the obtained film until the thickness of the adhesive layer became 1/10 of the thickness shown in table 1 and drying the same.

Stretching and annealing

The film with the adhesive layer formed was held by a tenter and stretched by 15% in the transverse direction. Thereafter, a heat treatment was performed under a nitrogen atmosphere at 1 ℃ per minute to raise the temperature from room temperature to 270 ℃ and maintained at that temperature for 2 hours.

Formation of an adhesive layer 2-

Using the obtained liquid crystal polymer film, a copper-clad laminate was produced in the same manner as in example 1.

Example 9

In example 9, a film was produced by a coating method.

Film forming process

The dispersion was coated on a treated surface of copper foil (Fukuda Metal Foil & Powder Co., ltd., CF-T4X-SV-18, thickness 18 μm) by reverse gravure method and dried at 120℃for 10 minutes, thereby obtaining a film precursor.

Formation of the adhesive layer 1-

The adhesive layer 1 was formed by applying the adhesive layer composition described in table 2 to the obtained film precursor until the thickness of the adhesive layer became 1/10 of the thickness described in table 2 and drying the same.

Annealing process-

The film precursor on which the adhesive layer 1 was formed was heated at 380 ℃ for 5 minutes under a nitrogen atmosphere.

Formation of an adhesive layer 2-

The composition for an adhesive layer described in table 2 was further applied onto the adhesive layer 1 until the thickness of the adhesive layer became the thickness described in table 2, and dried, thereby obtaining a laminate of copper foil/polymer film.

Using the obtained laminate of copper foil/polymer film, a copper-clad laminate was produced in the same manner as in example 1.

Comparative example 1

In comparative example 1, the film forming step was followed by the stretching step and the annealing step, and the adhesive layer was formed after the annealing step. Each step was performed in the same manner as in example 1, to obtain a liquid crystal polymer film. Using the obtained liquid crystal polymer film, a copper-clad laminate was produced in the same manner as in example 1.

Comparative example 2

In comparative example 2, the film forming step was followed by the stretching step and the annealing step, and the adhesive layer was formed after the annealing step. Each step was performed in the same manner as in example 4, to obtain a liquid crystal polymer film. Using the obtained liquid crystal polymer film, a copper-clad laminate was produced in the same manner as in example 1.

The measurement results of the dielectric loss tangent of the liquid crystal polymer film and the peel strength of the copper-clad laminate are shown in table 1. The types and thicknesses of the liquid crystal polymers, the types of the adhesive layers, the formation time points and thicknesses, and the film formation methods are shown in table 1. The time point of formation of the adhesive layer is referred to as "a" when the formation of the adhesive layer is performed immediately after the film formation step, and as "B" when the formation of the adhesive layer is performed immediately after the annealing step. In examples 1 to 8, it was confirmed that a mixed region including a liquid crystal polymer and an adhesive was formed in the liquid crystal polymer film, and thus the thickness of the mixed region was described. In example 9, it was confirmed that a mixed region including a polymer and an adhesive was formed in the polymer film, and thus the thickness of the mixed region was described.

In addition, regarding whether or not a mixed region is formed in the liquid crystal polymer film and the liquid crystal polymer film, the liquid crystal polymer film is cut in an oblique direction, and the obtained cross-sectional sample is evaluated by TOF-SIMS (time of flight secondary ion mass spectrometry), and a portion where a fragment derived from the liquid crystal polymer layer and a fragment derived from the layer a are observed at the same time is determined as the mixed region.

TABLE 1

TABLE 2

As shown in table 1, in examples 1 to 8, since the liquid crystal polymer layer including the liquid crystal polymer and the layer a disposed on at least one surface of the liquid crystal polymer layer were provided, the mixed region including the liquid crystal polymer and the material constituting the layer a was formed between the liquid crystal polymer layer and the layer a, and therefore, the adhesiveness between the liquid crystal polymer film and the metal was excellent.

As shown in table 2, in example 9, since the polymer layer including the polymer and the layer a disposed on at least one surface of the polymer layer were provided, a mixed region including the liquid crystal polymer and the material constituting the layer a was formed between the polymer layer and the layer a, and therefore, the adhesiveness between the polymer film and the metal was excellent.

On the other hand, in comparative examples 1 and 2, it was found that the mixed region containing the liquid crystal polymer and the material constituting the layer a was not formed, and the adhesion between the liquid crystal polymer film and the metal was poor.

Further, the invention of Japanese patent application 2021-024944 filed on 18, 2, 2021 is incorporated herein by reference in its entirety. All documents, patent applications, and technical specifications described in the present specification are incorporated by reference into the present specification to the same extent as if each document, patent application, and technical specification were specifically and individually indicated to be incorporated by reference.

Claims

1. A liquid crystal polymer film comprising:

a liquid crystal polymer layer comprising a liquid crystal polymer; a kind of electronic device with high-pressure air-conditioning system

A layer A disposed on at least one surface of the liquid crystal polymer layer,

a mixed region including the liquid crystal polymer and a material constituting the layer a is formed between the liquid crystal polymer layer and the layer a.

2. The liquid crystal polymer film according to claim 1, wherein,

the average thickness of the mixing region is 1nm to 10 mu m.

3. The liquid crystal polymer film according to claim 1 or 2, which has a dielectric loss tangent of 0.005 or less.

4. A liquid-crystalline polymer film according to any one of claim 1 to 3, wherein,

the layer a is an adhesive layer containing an adhesive.

5. The liquid crystal polymer film according to claim 4, wherein,

The adhesive comprises a compound having a functional group,

the functional group is at least 1 group selected from the group consisting of a group capable of covalent bonding, a group capable of ionic bonding, a group capable of hydrogen bonding, and a group capable of dipole-to-dipole interaction.

6. The liquid crystal polymer film according to claim 5, wherein,

the functional group is a group capable of covalent bonding.

7. The liquid crystal polymer film according to claim 6, wherein,

the group capable of covalent bonding is at least 1 selected from the group consisting of an epoxy group, an oxetanyl group, an isocyanate group, an acid anhydride group, a carbodiimide group, an N-hydroxy ester group, a glyoxal group, an imide ester group, a haloalkyl group, and a thiol group.

8. The liquid crystal polymer film according to claim 5, wherein,

the functional group is a group capable of ionic bonding, a group capable of hydrogen bonding, or a group capable of dipole-dipole interaction.

9. The liquid crystal polymer film according to any one of claims 1 to 8, wherein,

the melting point of the liquid crystal polymer is more than 280 ℃.

10. The liquid crystal polymer film according to any one of claim 1 to 9, wherein,

The liquid crystal polymer comprises structural units derived from an aromatic hydroxycarboxylic acid.

11. The liquid crystal polymer film according to any one of claim 1 to 9, wherein,

the liquid crystal polymer comprises at least 1 structural unit selected from the group consisting of structural units derived from an aromatic hydroxycarboxylic acid, structural units derived from an aromatic diol, and structural units derived from an aromatic dicarboxylic acid.

12. The liquid crystal polymer film according to any one of claims 1 to 11, wherein,

the liquid crystal polymer comprises an aromatic polyester amide.

13. A laminate having the liquid crystal polymer film according to any one of claims 1 to 12 and a metal layer or a metal wiring provided on at least one face of the liquid crystal polymer film.

14. The laminate according to claim 13, wherein,

the metal layer or the metal wiring has a group capable of interacting with the liquid crystal polymer film on a side surface in contact with the liquid crystal polymer film.

15. The laminate according to claim 14, wherein,

the group capable of interacting with the liquid crystal polymer film is an amino group.

16. The laminate according to any one of claims 13 to 15, wherein,

The peel strength between the liquid crystal polymer film and the metal layer is 0.5kN/m or more.

17. A polymer film, comprising:

a polymer layer containing at least 1 polymer selected from the group consisting of a fluorine-based polymer, a polymer containing a structural unit derived from a compound having a cyclic aliphatic hydrocarbon group and a group having an ethylenically unsaturated bond, a polyphenylene ether, and an aromatic polyether ketone; a kind of electronic device with high-pressure air-conditioning system

A layer A disposed on at least one side of the polymer layer,

a mixed region including the polymer and a material constituting the layer a is formed between the polymer layer and the layer a.