CN113166442A

CN113166442A - Method for producing modified particle, dispersion liquid, composition, and laminate

Info

Publication number: CN113166442A
Application number: CN201980080578.3A
Authority: CN
Inventors: 寺田达也; 细田朋也
Original assignee: Asahi Glass Co Ltd
Current assignee: AGC Inc
Priority date: 2018-12-05
Filing date: 2019-12-03
Publication date: 2021-07-23
Also published as: KR20210100092A; JP7444072B2; TWI815999B; TW202031693A; JPWO2020116461A1; WO2020116461A1

Abstract

The invention provides a method for producing modified particles having excellent dispersibility and capable of inhibiting surface unevenness of a layer, modified particles capable of forming a thin layer with inhibited surface unevenness, a dispersion liquid and a composition, and a thin laminate. The method for producing modified particles of the present invention is a method for producing modified particles, wherein a tetrafluoroethylene polymer base particle having a cumulative 50% by volume diameter of 0.01 to 100 [ mu ] m is subjected to a surface treatment to obtain modified particles obtained by introducing a polar group into the base particle. The surface treatment is preferably a plasma treatment or a corona treatment.

Description

Method for producing modified particle, dispersion liquid, composition, and laminate

Technical Field

The present invention relates to: a process for producing modified particles obtained by introducing a polar group into a vinyl fluoride polymer mother particle having a diameter of cumulative 50% on a volume basis, modified particles having excellent dispersibility obtained by introducing a polar group into a mother particle, a dispersion and a composition each comprising the modified particles, and a laminate.

Background

In a printed wiring board for transmitting a high-frequency signal, an insulating material having a small relative dielectric constant and a small dielectric loss tangent is used for the purpose of improving transmission performance. As the insulating material, a fluororesin is known. Further, a method of manufacturing a printed wiring board having excellent transmission performance has been proposed, in which a metal layer in a metal laminate (having a substrate, a resin layer in contact with the substrate and containing resin powder (resin particles) containing a fluororesin as a main component, and a metal layer in contact with the resin layer) is processed into a patterned circuit (see patent document 1).

In recent years, in order to make electronic devices smaller, a printed wiring board with a thinner profile is desired. In order to make the printed wiring board thin, the thickness of the resin layer needs to be made smaller.

In forming the resin layer, a dispersion in which resin particles are dispersed is used. In this case, when the dispersion liquid is prepared by using a mixer with a low stirring force, the resin particles are insufficiently dispersed and aggregates are generated. In the case of this dispersion, as the resin layer becomes thinner, the shape of the aggregate is reflected, and unevenness is likely to be formed on the surface. When the surface of the resin layer is uneven, the adhesion between the resin layer and the patterned circuit (metal layer) is reduced. In addition, the patterned circuit becomes long along the irregularities, and transmission performance may be degraded.

On the other hand, it is industrially disadvantageous to use a stirrer having a relatively strong shearing force (high stirring ability) in order to sufficiently disperse the resin particles in the dispersion liquid.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2016/017801

Disclosure of Invention

Technical problem to be solved by the invention

An object of the present invention is to provide a method for producing modified particles having excellent dispersibility and capable of suppressing surface irregularities of a layer, modified particles capable of forming a thin layer having suppressed surface irregularities, a dispersion liquid and a composition, and a thin laminate.

Technical scheme for solving technical problem

The present invention has the following technical contents.

< 1 > A process for producing modified particles, which comprises subjecting a tetrafluoroethylene polymer base particle having a cumulative 50% by volume of a particle diameter of 0.01 to 100 μm to surface treatment to obtain modified particles obtained by introducing a polar group into the base particle.

< 2 > the production process as described in < 2 >, wherein the surface treatment is a plasma treatment or a corona treatment.

The production method of < 3 > or < 2 > wherein the master batch is subjected to plasma treatment in an atmosphere containing at least 1 kind selected from the group consisting of argon, helium and oxygen.

The production process according to any one of < 4 > to < 1 > -3 >, wherein the tetrafluoroethylene-based polymer contains 99.5 mol% or more of a tetrafluoroethylene-based unit with respect to all units contained in the polymer.

The production process according to any one of < 5 > to < 1 > -3 >, wherein the tetrafluoroethylene-based polymer contains more than 0.5 mol% of units based on a comonomer other than tetrafluoroethylene with respect to all units contained in the polymer.

The production process of < 6 > is as defined in any one of < 1 > to < 5 >, wherein the tetrafluoroethylene polymer has at least 1 functional group selected from the group consisting of a carbonyl group-containing group, a hydroxyl group, an epoxy group, an oxetanyl group, an amino group, a cyano group and an isocyanate group.

The production method of any one of < 7 > to < 1 > -6 >, wherein the tetrafluoroethylene polymer is a hot-melt polymer having a melting point of 260 to 320 ℃.

< 8 > a modified particle obtained by surface-treating a tetrafluoroethylene polymer base particle having a cumulative 50% by volume of 0.01 to 100 μm diameter,

the modified particles have a polar group introduced into the base particles, and the zeta potential thereof is smaller than that of the base particles.

< 9 > the modified particle as < 8 >, wherein the tetrafluoroethylene-based polymer has at least 1 functional group selected from the group consisting of a carbonyl group-containing group, a hydroxyl group, an epoxy group, an oxetanyl group, an amino group, a cyano group and an isocyanate group.

(iii) modified particles (3) < 10 > such as < 8 > or < 9 >, wherein the zeta potential of the master batch is X and the zeta potential of the modified particles immediately after the surface treatment is Y₀When, Y₀The value of/X is 1.3 or more.

The modified particle described in any one of < 11 > to < 8 > - < 10 >, wherein zeta potential of the modified particle immediately after the surface treatment is represented by Y₀And zeta potential of the modified particles after 30 days at 25 ℃ from the completion of the surface treatment was recorded as Y₃₀When, Y₃₀/Y₀Is 0.8 or more.

The modified particle of < 12 > as defined in any of < 8 > -11 > wherein 100g of the modified particle is dispersed in 100g of water to prepare a dispersion, and the dispersion after 30 days at 25 ℃ is passed through a mixer according to JIS Z8801-1: in the case of a 200 mesh screen of 2006, the amount of residue remaining on the screen is 5g or less.

< 13 > a dispersion liquid comprising the modified particle described in any one of < 8 > -to < 12 > and a liquid medium in which the modified particle is dispersed.

< 14 > a composition comprising the modified particle described in any one of < 8 > -to < 12 > and another polymer different from the tetrafluoroethylene-based polymer, the modified particle being dispersed in the other polymer.

< 15 > a laminate comprising a substrate and a layer comprising the modified particle described in any one of < 8 > to < 12 > provided on the surface of the substrate.

Effects of the invention

According to the present invention, modified particles having excellent dispersibility and being capable of suppressing unevenness of the layer surface can be easily produced. Further, according to the modified particles, the dispersion liquid, and the composition of the present invention, a thin layer in which surface unevenness is suppressed can be formed.

The laminate having the layer is thin, has suppressed surface irregularities, and when used as a printed wiring board, has high adhesion between a patterned circuit and the layer and excellent transmission performance.

Detailed Description

The following definitions of terms apply throughout the present specification and claims.

The "hot-melt polymer" is a polymer having an MFR of 0.01 to 1000g/10 min at a temperature higher than the melting point of the polymer by 20 ℃ or more under a load of 49N.

The "melting point of the polymer" is a temperature corresponding to the maximum value of the melting peak of the polymer measured by Differential Scanning Calorimetry (DSC).

"MFR of polymer" means, JIS K7210-1: 2014 (corresponding to the melt flow rate specified in international standard ISO 1133-1: 2011).

"D50 of particles" means a particle size (cumulative 50% diameter on a volume basis) at which a cumulative volume reaches 50% by obtaining a cumulative curve with the total volume of the particle group as 100% by measuring the particle size distribution of the particles by a laser diffraction scattering method.

"D90 of particles" means a particle size distribution of particles measured by a laser diffraction scattering method, and a cumulative curve obtained by taking the total volume of the particle group as 100%, and a point on the cumulative curve where the cumulative volume reaches 90% (cumulative 90% diameter on a volume basis).

That is, D50 and D90 of the particles are a volume-based cumulative 50% diameter and a volume-based cumulative 90% diameter of the powder as the particle aggregate.

"zeta potential" means "zeta potential of distilled water at pH 7.0".

The "heat-resistant resin" is a polymer compound having a melting point of 280 ℃ or higher or JISC 4003: 2010(IEC 60085: 2007) wherein the maximum continuous use temperature is 121 ℃ or higher.

The "monomer-based unit" is a generic name of a radical formed directly by polymerization of 1 molecule of a monomer and a radical obtained by chemically converting a part of the radical. In the present specification, the monomer-based unit is also abbreviated as "unit".

The method for producing modified particles of the present invention is a method for obtaining modified particles obtained by introducing a polar group into a tetrafluoroethylene polymer (hereinafter also referred to as "F polymer") having a D50 of 0.01 to 100 μm by surface-treating a base particle of the polymer.

Since the modified particles obtained by the method for producing modified particles have a plurality of polar groups introduced to the surface of the base particles, the dispersibility of the modified particles in a liquid dispersion is improved when the modified particles are dispersed in a liquid medium to prepare a dispersion. It is considered that the polar group is introduced not only to the surface of the mother particle but also to a region of a predetermined depth from the surface.

The masterbatch of the present invention comprises polymer F. The master batch may contain other components than the F polymer, if necessary.

The amount of the F polymer contained in the base particle is preferably 80% by mass or more, more preferably 85% by mass or more, further preferably 90% by mass or more, and particularly preferably 100% by mass. When the modified particles obtained from the mother particle containing the F polymer in the above amount are used, the transmission performance when a layer formed of the modified particles (hereinafter also referred to as "F layer") is used as a printed wiring board by forming a patterned circuit on the surface thereof is improved. The F polymer may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

As other components, there may be mentioned: polymers other than the polymer F, inorganic fillers having a low dielectric constant or dielectric loss tangent, and rubbers.

As the other polymer, a compound which does not impair the electrical reliability of the F layer is preferable, and examples thereof include: fluoropolymers (polytetrafluoroethylene, etc.) other than the F polymer, aromatic polyesters, polyamideimides, thermoplastic polyimides, polyphenylene oxides.

The F polymer is preferably a hot melt polymer. The melting point of the hot-melt polymer is preferably 260 to 320 ℃, more preferably 280 to 320 ℃, further preferably 295 to 315 ℃, and particularly preferably 295 to 310 ℃. When the melting point is not less than the lower limit, the heat resistance of the modified particles (base particles) is improved. When the melting point is not more than the above upper limit, the heat-fusible polymer is more easily melted.

The melting point of the heat-fusible polymer can be adjusted by the kind and ratio of units constituting the polymer, the molecular weight, and the like. For example, the melting point of the hot-melt polymer tends to increase as the proportion of tetrafluoroethylene-based units (hereinafter also referred to as "TFE units") increases.

The MFR of the hot-melt polymer is preferably 0.01 to 1000g/10 min, more preferably 0.05 to 1000g/10 min, still more preferably 0.1 to 1000g/10 min, yet more preferably 0.5 to 100g/10 min, particularly preferably 1 to 30g/10 min, most preferably 5 to 20g/10 min at a temperature higher than the melting point by 20 ℃ or higher. When the MFR is not less than the lower limit, the heat-fusible polymer is more easily melted, and the surface smoothness and appearance of the F layer are improved. When the MFR is not more than the above upper limit, the mechanical strength of the F layer is improved.

MFR is an index of the molecular weight of a hot-melt polymer, and a large MFR indicates a small molecular weight, and a small MFR indicates a large molecular weight.

The MFR of the hot-melt polymer can be adjusted depending on the production conditions. For example, if the polymerization time at the time of polymerization of the monomer is shortened, the MFR of the heat-fusible polymer tends to become large.

The relative dielectric constant of the F polymer is preferably 2.5 or less, more preferably 2.4 or less. The lower the relative dielectric constant of the F polymer, the further the transmission properties of the F layer are improved. The lower limit of the relative dielectric constant is usually 2.0. The relative dielectric constant of the F polymer can be adjusted depending on the proportion of TFE units.

As the F polymer, there may be mentioned: tetrafluoroethylene-perfluoro (alkyl vinyl ether) copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, and polymers obtained by introducing at least 1 functional group (hereinafter also referred to as "adhesive group") selected from a carbonyl group, a hydroxyl group, an epoxy group, an oxetanyl group, an amino group, a cyano group, and an isocyanate group into these, and modified polytetrafluoroethylene. Further, polytetrafluoroethylene may be used as the F polymer as long as it exhibits thermal fusibility.

Examples of the modified polytetrafluoroethylene include: (i) tetrafluoroethylene (hereinafter, also referred to as "TFE") and a very small amount of CH₂＝CH(CF₂)₄A copolymer of F, (ii) a copolymer of the copolymer of (i) above, and further a monomer having an extremely small amount of an adhesive group (hereinafter also referred to as "adhesive monomer"), (iii) a copolymer of TFE and an extremely small amount of an adhesive monomer, (iv) polytetrafluoroethylene having an adhesive group introduced thereto by plasma treatment or the like, and (v) a copolymer of (i) above having an adhesive group introduced thereto by plasma treatment or the like.

The modified polytetrafluoroethylene preferably contains 99.5 mol% or more, more preferably 99.9 mol% or more of TFE-based units based on all units contained in the polymer.

Among them, the F polymer is preferably a polymer having an adhesive group introduced therein (a polymer having an adhesive group). The F polymer has a highly reactive adhesive group. Therefore, when the surface treatment is performed on the base particle containing the F polymer, the polar group is unexpectedly introduced into the originally low-reactive main chain portion, possibly due to the presence of the adhesive group, together with the conversion of the adhesive group into the polar group, depending on the type of the adhesive group.

Further, the present inventors have found that the introduced polar group is less likely to decrease with time. This is considered to be because the polar groups introduced to the surface of the mother particle are prevented from being buried in the mother particle by an electrical repulsive force from the adhesive groups present in a large amount in the mother particle.

Examples of the method for introducing an adhesive group into the F polymer include: (i) a method of copolymerizing a fluorine monomer with an adhesive monomer, and (ii) a method of contacting the F polymer with a surface treatment agent.

The surface treatment agent may be a metal sodium solution such as a complex of metal sodium and naphthalene, as long as it can introduce an adhesive group into the F polymer.

The F polymer is preferably a unit having an adhesive group (hereinafter also referred to as "adhesive unit") and a fluorocopolymer having a TFE unit (hereinafter also referred to as "copolymer a"), from the viewpoint of excellent adhesion between the F layer and another layer. The copolymer a may contain other units than the adhesive unit and the TFE unit.

The copolymer a preferably comprises more than 0.5 mol% of units other than TFE units, relative to all units of the polymer.

The adhesive group is preferably a carbonyl group, from the viewpoint of excellent mechanical pulverizability of the raw material (particles, granules, etc.) containing the copolymer a and excellent adhesion between the F layer and the metal layer (metal foil).

As the carbonyl group-containing group, there may be mentioned: a hydrocarbon group having a carbonyl group between carbon atoms, a carbonate group, a carboxyl group, a haloformyl group, an alkoxycarbonyl group, an acid anhydride residue, a polyfluoroalkoxycarbonyl group, and a fatty acid residue.

The carbonyl group-containing group is preferably at least 1 selected from the group consisting of the above hydrocarbon group, carbonate group, carboxyl group, haloformyl group, alkoxycarbonyl group, and acid anhydride residue, and more preferably at least one of the carboxyl group and acid anhydride residue, from the viewpoint of further improving the mechanical pulverizability of the raw material containing the copolymer a and the adhesion between the F layer and the metal layer. In addition, the carbonyl-containing group comprises an amide group.

The hydrocarbon group includes an alkylene group having 2 to 8 carbon atoms. In addition, the number of carbons of the alkylene group does not include the number of carbons constituting the carbonyl group.

Examples of the haloformyl group include — C (═ O) -F and — C (═ O) Cl.

Examples of the alkoxy group in the alkoxycarbonyl group include a methoxy group and an ethoxy group.

The number of the adhesive groups of the adhesive monomer may be 1, or 2 or more. In the case where the adhesive monomer has 2 or more adhesive groups, the 2 or more adhesive groups may be the same or different.

Examples of the adhesive monomer include: a monomer having a carbonyl group, a monomer having a hydroxyl group, a monomer having an epoxy group, a monomer having an oxetanyl group, a monomer having an amino group, a monomer having a cyano group, and a monomer having an isocyanate group. The adhesive monomer is preferably a monomer having a carbonyl group, from the viewpoint of excellent mechanical pulverizability of the raw material containing the copolymer a and excellent adhesion between the F layer and the metal layer.

As the monomer having a carbonyl group, there may be mentioned: cyclic monomer having acid anhydride residue, monomer having carboxyl group, vinyl ester, (meth) acrylic ester, CF₂＝CFOR^f1CO₂X¹(wherein, R^f1Is a C1-10 perfluoroalkylene group or a C2-10 perfluoroalkylene group having an etheric oxygen atom between carbon atoms, X¹Is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms).

Examples of the cyclic monomer having an acid anhydride residue include: unsaturated dicarboxylic acid anhydride (itaconic anhydride (hereinafter also referred to as "IAH"), citraconic anhydride (hereinafter also referred to as "CAH"), 5-norbornene-2, 3-dicarboxylic anhydride (alias: nadic anhydride; hereinafter also referred to as "NAH"), maleic anhydride, and the like.

As the monomer having a carboxyl group, there may be mentioned: unsaturated dicarboxylic acids (itaconic acid, citraconic acid, 5-norbornene-2, 3-dicarboxylic acid, maleic acid, etc.), unsaturated monocarboxylic acids (acrylic acid, methacrylic acid, etc.).

Examples of vinyl esters include: vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl pivalate, vinyl benzoate, vinyl crotonate.

Examples of the (meth) acrylic acid ester include: poly (fluoroalkyl) acrylate, poly (fluoroalkyl) methacrylate.

The monomer having a carbonyl group is preferably a cyclic monomer having an acid anhydride residue, and more preferably IAH, CAH or NAH, from the viewpoint of excellent thermal stability of the modified particle (base particle) and further improvement in adhesion between the F layer and the metal layer. When IAH, CAH or NAH is used, the copolymer a having an acid anhydride residue can be easily produced. As the monomer having a carbonyl group, NAH is particularly preferable in terms of easily improving the adhesiveness of the F layer formed of the modified particles.

As the monomer having a hydroxyl group, there may be mentioned: vinyl esters having a hydroxyl group, vinyl ethers having a hydroxyl group, allyl ethers having a hydroxyl group, (meth) acrylic esters having a hydroxyl group, hydroxyethyl crotonate, allyl alcohol.

As the monomer having an epoxy group, there can be mentioned: unsaturated glycidyl ethers (allyl glycidyl ether, 2-methallyl glycidyl ether, vinyl glycidyl ether, etc.), unsaturated glycidyl esters ((glycidyl (meth) acrylate, etc.).

Examples of the monomer having an isocyanate group include: 2- (meth) acryloyloxyethyl isocyanate, 2- (2- (meth) acryloyloxyethoxy) ethyl isocyanate, 1-bis ((meth) acryloyloxymethyl) ethyl isocyanate.

The adhesive monomers may be used alone in 1 kind, or in combination of 2 or more kinds.

Examples of the other units than the adhesive unit and the TFE unit include: a perfluoro (alkyl vinyl ether) (hereinafter also referred to as "PAVE unit"), a hexafluoropropylene (hereinafter also referred to as "HFP") unit (hereinafter also referred to as "HFP unit"), and a unit based on an adhesive monomer, TFE, PAVE, and another monomer other than HFP.

As PAVE, there may be mentioned: CF (compact flash)₂＝CFOCF₃、CF₂＝CFOCF₂CF₃、CF₂＝CFOCF₂CF₂CF₃(hereinafter also referred to as "PPVE"), CF₂＝CFOCF₂CF₂CF₂CF₃、CF₂＝CFO(CF₂)₈F, etc., preferably PPVE.

PAVE can be used alone in 1 kind, also can be used more than 2 kinds to combine.

As other monomers, there may be mentioned: other fluorine-containing monomers (excluding adhesive monomers, TFE, PAVE and HFP), and other non-fluorine-containing monomers (excluding adhesive monomers).

Examples of other fluorine-containing monomers include: vinyl fluoride, vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, CF₂＝CFOR^f3SO₂X³(wherein, R^f3Is a C1-10 perfluoroalkylene group or a C2-10 perfluoroalkylene group having an etheric oxygen atom between carbon atoms, X³Is a halogen atom or a hydroxyl group), CF₂＝CF(CF₂)_pOCF＝CF₂(wherein p is 1 or 2), CH₂＝CX⁴(CF₂)_qX⁵(wherein, X⁴Is a hydrogen atom or a fluorine atom, q is an integer of 2 to 10, X⁵Hydrogen atom or fluorine atom), perfluoro (2-methylene-4-methyl-1, 3-dioxolane). The other fluorine-containing monomers may be used alone in 1 kind, or in combination of 2 or more kinds.

As CH₂＝CX⁴(CF₂)_qX⁵Examples thereof include: CH (CH)₂＝CH(CF₂)₂F、CH₂＝CH(CF₂)₃F、CH₂＝CH(CF₂)₄F、CH₂＝CF(CF₂)₃H、CH₂＝CF(CF₂)₄H, preferably CH₂＝CH(CF₂)₄F、CH₂＝CH(CF₂)₂F。

Examples of the other non-fluorine-containing monomer include ethylene and propylene, and ethylene is preferable. The other fluorine monomers may be used alone in 1 kind, or in combination of 2 or more kinds.

As the other monomer, other fluorine monomers and other non-fluorine monomers may be used in combination.

The copolymer a may have an adhesive group as a terminal group bonded to a terminal of the main chain. The adhesive group as the terminal group is preferably an alkoxycarbonyl group, a carbonate group, a carboxyl group, a fluoroformyl group, an acid anhydride residue, or a hydroxyl group. The adhesive group can be introduced by appropriately selecting a radical polymerization initiator, a chain transfer agent, and the like used in the production of the copolymer a.

The proportion of the adhesive unit in the copolymer a in all the units constituting the copolymer a is preferably 0.002 to 3 mol%, more preferably 0.01 to 1 mol%, and still more preferably 0.02 to 0.5 mol%. When the proportion of the adhesive means is not less than the lower limit, the amount of the polar group introduced by the surface treatment can be sufficiently increased to improve the dispersibility of the modified particle in the composition and the adhesion to other polymers, whereby the adhesion between the layer F and other layers (metal layer and the like) can be further improved. When the proportion of the adhesive unit is not more than the above upper limit, the heat resistance, color tone, and the like of the modified particles become good.

In the copolymer a, the proportion of the adhesive unit to 10000 carbon atoms in the main chain is preferably 150 or less, more preferably 50 or less, further preferably 25 or less, and particularly preferably 15 or less. The proportion of the above-mentioned adhesive means is preferably 0.1 or more, more preferably 0.5 or more, and still more preferably 1 or more. The copolymer a containing the adhesive unit in such a ratio can be introduced with a necessary and sufficient amount of polar groups.

The copolymer a is preferably a copolymer a1 having a binder unit, a TFE unit, and a PAVE unit, and a copolymer a2 having a binder unit, a TFE unit, and an HFP unit, and more preferably a copolymer a1, from the viewpoint of improving the heat resistance of the modified particles (mother particles).

The copolymer a1 may have at least one of HFP units and other units as needed. That is, the copolymer a1 may be a copolymer having an adhesive unit, a TFE unit, and a PAVE unit, a copolymer having an adhesive unit, a TFE unit, a PAVE unit, and an HFP unit, a copolymer having an adhesive unit, a TFE unit, a PAVE unit, and other units, or a copolymer having an adhesive unit, a TFE unit, a PAVE unit, an HFP unit, and other units.

The copolymer a1 is preferably a copolymer having a unit based on a monomer having a carbonyl group, a TFE unit, and a PAVE unit, and more preferably a copolymer having a unit based on a cyclic monomer having an acid anhydride residue, a TFE unit, and a PAVE unit, from the viewpoint of further improving the mechanical pulverizability of the raw material containing the copolymer a1 and the adhesion between the F layer and the metal layer.

Preferred specific examples of the copolymer a1 include: copolymers having TFE units, PPVE units, and NAH units; a copolymer having TFE units, PPVE units, and IAH units; copolymers having TFE units, PPVE units, and CAH units.

The proportion of TFE units in the copolymer A1 in all units constituting the copolymer A1 is preferably 90 to 99.89 mol%, more preferably 96 to 98.95 mol%. In this case, the electrical properties (low dielectric constant, etc.), heat resistance, chemical resistance, etc. of the F layer are easily balanced with the heat fusion property, stress crack resistance, etc. of the copolymer a 1.

The proportion of the PAVE units in the copolymer a1 in all the units constituting the copolymer a1 is preferably 0.1 to 9.99 mol%, more preferably 1 to 9.95 mol%. In this case, the thermal fusibility of the copolymer a1 can be easily adjusted.

The total of the adhesive unit, the TFE unit, and the PAVE unit in the copolymer a1 is preferably 90 mol% or more, and more preferably 98 mol% or more. The upper limit is 100 mol%.

The copolymer a2 may have at least one of PAVE units and other monomer units as desired. That is, the fluorocopolymer a2 may be a copolymer having an adhesive unit, a TFE unit, and an HFP unit, a copolymer having an adhesive unit, a TFE unit, an HFP unit, and a PAVE unit, a copolymer having an adhesive unit, a TFE unit, an HFP unit, and another monomer unit, or a copolymer having an adhesive unit, a TFE unit, an HFP unit, a PAVE unit, and another unit.

The copolymer a2 is preferably a copolymer comprising a unit based on a monomer having a carbonyl group, a TFE unit, and an HFP unit, and more preferably a copolymer comprising a unit based on a cyclic monomer having an acid anhydride residue, a TFE unit, and an HFP unit, from the viewpoint of further improving the mechanical pulverizability of the raw material containing the copolymer a2 and the adhesion between the F layer and the metal layer.

Preferred specific examples of the copolymer a2 include: a copolymer having a TFE unit, a HFP unit and a NAH unit; copolymers having TFE units, HFP units, and IAH units; a copolymer having TFE units, HFP units and CAH units.

The proportion of TFE units in the copolymer a2 in all units constituting the copolymer a2 is preferably 90 to 99.89 mol%, more preferably 92 to 96 mol%. In this case, the electrical properties (low dielectric constant, etc.), heat resistance, chemical resistance, etc. of the F layer are easily balanced with the heat fusion property, stress crack resistance, etc. of the copolymer a 2.

The proportion of the HFP unit in the copolymer a2 in all the units constituting the copolymer a2 is preferably 0.1 to 9.99 mol%, more preferably 2 to 8 mol%. When the proportion of HFP units is within the above range, the heat fusibility of the copolymer a2 is further improved.

The total ratio of the adhesive unit, the TFE unit, and the HFP unit in the copolymer a2 is preferably 90 mol% or more, and more preferably 98 mol% or more. The upper limit is 100 mol%.

The proportion of each unit in the copolymer a can be determined by NMR analysis such as melt Nuclear Magnetic Resonance (NMR) analysis, fluorine content analysis, and infrared absorption spectrum analysis. For example, the proportion (mol%) of the adhesive unit in all the units constituting the copolymer A can be determined by a method such as infrared absorption spectrum analysis as described in Japanese patent laid-open No. 2007-314720.

Examples of the method for producing the copolymer a include: (i) a method of polymerizing an adhesive monomer and TFE with PAVE, FEP, or other monomers as needed; (ii) a method in which a fluorocopolymer having a unit having a functional group which generates an adhesive group by thermal decomposition and a TFE unit is heated to thermally decompose the functional group to generate an adhesive group (e.g., a carboxyl group); (iii) the method of graft-polymerizing an adhesive monomer onto a fluorocopolymer having a TFE unit is preferably the method of the above (i).

The polymerization method (bulk polymerization method, solution polymerization method, suspension polymerization method, emulsion polymerization method, etc.) is not particularly limited and may be appropriately set. Further, the amounts and kinds of the solvent, polymerization initiator, and chain transfer agent used in the polymerization may be appropriately set.

The polymerization conditions (temperature, pressure, time, etc.) may be appropriately set according to the kind of the monomer used.

The D50 of the master batch is 0.01-100 mu m. The lower limit of D50 is preferably 0.1. mu.m, more preferably 0.5. mu.m, and still more preferably 0.8. mu.m.

The upper limit of D50 is preferably 30 μm, more preferably 6 μm, still more preferably 3 μm, particularly preferably 2.7 μm, most preferably 2.5. mu.m. When the D50 content of the base particles is not less than the lower limit, the modified particles obtained are less likely to aggregate when dispersed in a liquid medium, and are excellent in dispersibility in a dispersion liquid and in an F layer. When the D50 of the base particles is not more than the above upper limit, surface irregularities can be suppressed even when the F layer is thin. In addition, the filling rate of the modified particles in the F layer can be improved, and the transmission performance of the F layer is improved.

The D90 of the masterbatch is preferably 2.0 to 150. mu.m, more preferably 2.5 to 4 μm, still more preferably 2.7 to 3.9. mu.m, and particularly preferably 2.9 to 3.9. mu.m. When the D90 content of the base particles is not less than the lower limit, the modified particles obtained are less likely to aggregate when dispersed in a liquid medium, and are excellent in dispersibility in a dispersion liquid and in an F layer. When D90 of the base particles is not more than the above upper limit, unevenness of the surface of the F layer can be suppressed.

In addition, D50 and D90 of the modified particles of the present invention are substantially equal to D50 and D90 of the mother particles.

Commercially available particles may be used as the base particles, or particles produced by the following method may be used.

The method for producing the master batch includes: (i) a method in which a polymer F is obtained by a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method, and after an organic solvent or an aqueous medium is removed to obtain particles, the particles are pulverized by a mechanical pulverization treatment as needed and classified; (ii) a method comprising melt-kneading the polymer F and, if necessary, other components, pulverizing the kneaded product by mechanical pulverization treatment, and classifying the pulverized product, if necessary.

The mechanical pulverization process is a process of pulverizing a raw material using a pulverizer that exerts at least one of a shearing force and a crushing force sufficient to crush (pulverize) the raw material.

As the pulverizer, there may be mentioned: jet mill, hammer mill, pin mill, bead mill, turbo mill, preferably jet mill, bead mill, pin mill, more preferably jet mill. By these methods, the master batch of the target D50 can be easily obtained with a small number of mechanical pulverization treatments, and therefore the production efficiency of the finally obtained master batch is further improved.

As the jet mill, there can be mentioned: a collision type in which particles are caused to collide with each other or with a collision body (target) to be pulverized, a swirling airflow type and a circulation type in which particles are caused to collide with each other in a pulverization region formed by a plurality of pulverization nozzles arranged in a circulating airflow to be pulverized, a fluidized bed type in which particles are caused to collide with each other and to rub in a fluidized bed to be pulverized, a supersonic type, and the like.

Regarding the impact type, rotating air flow type, circulation type, and fluidized bed type jet mills, page 162 of "advanced grinding technology and application (tip grinding technology と application)" written by the japan powder industry technical society (NGT corporation, limited エヌジーティー) is described in detail.

As the impact type jet mill, there can be mentioned: a pulverizer that discharges a fluid such as compressed air from a nozzle and causes particles to collide with each other in a high-speed air turbulence generated in a jet mill to pulverize the fluid, and a pulverizer that transports particles in a high-speed air flow and causes the particles to collide with a collision body to pulverize the particles.

Commercially available products of the jet mill include: cross Jet Mill (manufactured by Tanbo iron works Co., Ltd.); Jet-O-Mill, A-O Jet Mill, Sanitary AOM, Co-Jet, Single Track Jet Mill, Super STJ Mill (all manufactured by refreshing industries, Ltd.); current Jet Mill (Nisshin engineering Co., Ltd.); ulmax (manufactured by Nissan engineering Co., Ltd.); supersonic Jet Mill PJM type, Supersonic Jet Mill CPY type, Supersonic Jet Mill LJ-3 type, and Supersonic Jet Mill I type (each manufactured by Yokogaku Kogyo Co., Ltd., Japan, ニューマチック, Co., Ltd.); oppos Jet Mill, Micron Jet-T model, Spiral Jet Mill, Micron Jet-Q MJQ model (all produced by Mikrang, Ltd.); a fluidized bed jet mill (manufactured by japan coke industry co.); a nano-mill (product of Deshou works Co., Ltd.).

As the Jet Mill, a Single Track Jet Mill (Single Track Jet Mill) is preferable in view of excellent productivity of the master batch.

The pulverizing pressure of the jet mill is preferably 0.5 to 2MPa, more preferably 0.6 to 0.9 MPa. When the pulverizing pressure is not less than the lower limit, the desired D50 mother particles can be easily obtained with a small number of mechanical pulverization treatments. If the pulverization pressure is not higher than the upper limit, the pulverization of the raw material is excellent.

The treatment rate of the jet mill is preferably 5 to 80kg/hr, more preferably 8 to 50 kg/hr. If the processing speed is higher than the lower limit value, the productivity of the master batch is improved. When the processing speed is not higher than the upper limit, the particles having a relatively large particle size (hereinafter, also referred to as "coarse particles") are less likely to be mixed into the base particles.

The number of mechanical pulverization treatments may be any number as long as the desired D50 master batch can be obtained. The number of mechanical pulverization treatments is preferably small, and more preferably 1 time, from the viewpoint of productivity of the base particles.

The classification is a treatment of removing at least one of coarse particles and particles having an excessively small particle diameter (hereinafter also referred to as "fine particles").

Examples of the classification method include: screening and air classification, and air classification is preferable from the viewpoint of operability and classification accuracy. As the classifier used for the air classification, a precision air classifier is preferable from the viewpoint of productivity and classification accuracy.

In the classification, a jet mill apparatus or the like provided with a classifier may be used, and the classification may be performed continuously after the mechanical pulverization treatment of the particles.

By subjecting the mother particles obtained as described above to surface treatment, a polar group is introduced at least into the surface of the mother particles to obtain modified particles.

As the surface treatment, there may be mentioned: plasma treatment, corona treatment, glow discharge treatment, sputtering treatment. In addition, as the polar group, there can be mentioned: carboxyl, carboxylate, aldehyde group, hydroxyl and amino.

As the surface treatment, plasma treatment or corona treatment is preferable, and plasma treatment is more preferable, from the viewpoint of easily obtaining modified particles having excellent dispersibility and easily suppressing irregularities on the surface of the F layer. In particular, the plasma treatment can make the amount of polar groups introduced into the master batch sufficiently large.

As a plasma irradiation apparatus used for plasma processing, there are exemplified: a device of a high-frequency induction type, a capacitive coupling type electrode type, a corona discharge electrode-plasma spray type, a parallel flat plate type, a remote plasma type, an atmospheric pressure plasma type, an ICP type high-density plasma type is used.

The gas used for the plasma treatment is selected depending on the kind of polar group to be introduced, and examples thereof include: hydrogen, oxygen, nitrogen, noble gases (argon, helium), ammonia. From the viewpoint of easily obtaining modified particles having excellent dispersibility and easily controlling the surface irregularities of the F layer, it is preferable to contain at least 1 gas selected from argon, helium, and oxygen. Further, when these gases are used, a group containing an oxygen atom is easily introduced as a polar group.

In plasma processing, the energy (about 1 to 10 eV) of generated electrons is controlled by adjusting the gap between electrodes, the output of the apparatus, and the like, and a processing time is set.

The treatment time of the plasma treatment is preferably 0.1 to 60 minutes, more preferably 1 to 40 minutes, and further preferably 2 to 30 minutes.

The modified particles thus obtained contain an F polymer and have a polar group introduced into a mother particle having a D50 value of 0.01 to 100 μm. The introduction of the polar group makes the zeta potential of the modified particles smaller than that of the base particles.

The smaller zeta potential improves the dispersibility of the modified particles in the liquid medium. Further, since aggregation is not likely to occur in the dispersion or the composition, the modified particles are monodisperse in the F layer, and surface irregularities can be suppressed even when the F layer is thin. Since the modified particles have excellent dispersibility, the modified particles can be easily dispersed in a liquid medium by mechanical stirring. Further, it is not necessary to change the polymerization step for obtaining the polymer F, and it is industrially advantageous.

Here, the zeta potential of the master batch was X [ mV ]]The zeta potential of the modified particles immediately after the surface treatment was represented by Y₀[mV]When, Y₀The ratio of/X is preferably 1.3 or more, more preferably 1.3 to 3, and still more preferably 1.5 to 2.5. If Y is₀when/X is not less than the lower limit value, the dispersibility of the modified particles in the liquid medium is further improved. In addition, if Y₀if/X exceeds the upper limit value, further increase in the effect cannot be expected.

As described above, since the embedding of the introduced polar group in the base particles is suppressed, the dispersion can be stored stably for a long period of time.

The degree of suppression can be expressed by the degree of change in zeta potential. Specifically, the zeta potential of the modified particles after 30 days at 25 ℃ after completion of the surface treatment was represented as Y₃₀[mV]When, Y₃₀/Y₀Preferably 0.8 or more, more preferably 0.85 or more, and further preferably 0.9 or more. If Y is₃₀/Y₀When the amount is changed within the above range, the polar group is considered to be sufficiently less buried in the master batch. In addition, Y₃₀/Y₀The upper limit value of (2) is 1.

When the polar group is buried in the mother particle, the zeta potential of the modified particle increases (changes in the direction toward 0 mV), and the modified particle aggregates. Therefore, the degree of inhibition can also be expressed by the degree of aggregation of the modified particles. Specifically, 100g of the modified particles were dispersed in 100g of water to prepare a dispersion, and the dispersion after 30 days at 25 ℃ was measured by JIS Z8801-1: in the case of a 200 mesh screen of 2006, the amount of residue remaining on the screen is preferably 5g or less, more preferably 3g or less. If the amount of the residue is within the above range, the burying of the polar group in the master batch is considered to be sufficiently small.

The dispersion liquid of the present invention comprises the above-mentioned modified particles and a liquid medium in which the modified particles are dispersed, and further, the dispersion liquid of the present invention may contain at least 1 of a surfactant, an antifoaming agent and an inorganic filler as required.

The above ingredients were mixed and stirred to obtain the dispersion.

Examples of the dispersing machine used for dispersion include: homomixer, high speed mixer, ultrasonic disperser, homogenizer, wet mill, bead mill, wet jet mill.

As the liquid medium, there may be mentioned: water, alcohols (methanol, ethanol, etc.), nitrogen-containing compounds (N, N-dimethylformamide, N-dimethylacetamide, N-methyl-2-pyrrolidone, etc.), sulfur-containing compounds (dimethyl sulfoxide, etc.), ethers (diethyl ether, dioxane, etc.), esters (ethyl lactate, ethyl acetate, etc.), ketones (methyl ethyl ketone, methyl isopropyl ketone, etc.), glycol ethers (ethylene glycol monoisopropyl ether, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.). The liquid medium may be used alone in 1 kind, or in combination of 2 or more kinds. In addition, the liquid medium is preferably unreactive or poorly reactive with the F polymer.

As the surfactant, there may be mentioned: nonionic surfactants, anionic surfactants, cationic surfactants, and the like. Among them, nonionic surfactants are preferable as the surfactant. The surfactant may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

As the defoaming agent, there can be mentioned: silicone-based or fluorosilicone-based emulsion type, self-emulsifying type, oil compound type, solution type, powder type, and solid type. In addition, the defoaming agent may be appropriately selected depending on the liquid medium used. In particular, in the case of a liquid medium other than an aqueous solvent, it is preferable to use a hydrophilic or water-soluble silicon-based defoaming agent in order to allow the defoaming agent to exist at the interface between the liquid medium and air rather than at the interface between the liquid medium and the F polymer. The defoaming agent can be used singly or in combination of 2 or more.

As the inorganic filler, there may be mentioned: silica, clay, talc, calcium carbonate, mica, diatomaceous earth, alumina, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, basic magnesium carbonate, zinc carbonate, barium carbonate, dawsonite (ドーソナイト), hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, montmorillonite, bentonite, activated clay, sepiolite, imogolite, sericite, glass fiber, glass bead, silica type hollow sphere (シリカ type バルーン), carbon black, carbon nanotube, carbon nanohorn, graphite, carbon fiber, hollow glass sphere (ガラスバルーン), carbo-firing (carbon バーン), wood flour, zinc borate, and the like. The inorganic filler may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The inorganic filler may be porous or non-porous (dense).

The inorganic filler may be surface-treated with a surface-treating agent such as a silane coupling agent or a titanate coupling agent in order to improve dispersibility in the dispersion.

The amount of the liquid medium contained in the dispersion is preferably 1 to 1000 parts by mass, more preferably 10 to 500 parts by mass, and still more preferably 30 to 250 parts by mass, per 100 parts by mass of the modified particles. When the amount of the liquid medium is within the above range, the coating property of the dispersion liquid at the time of film formation is good. Further, if the amount of the liquid medium is equal to or less than the above upper limit, the amount of the liquid medium used is small, and thus poor appearance of the F layer affected by the removal of the liquid medium is less likely to occur.

When the dispersion liquid contains a surfactant, the amount of the surfactant contained in the dispersion liquid is preferably 1 to 30 parts by mass, more preferably 3 to 20 parts by mass, and still more preferably 5 to 10 parts by mass, per 100 parts by mass of the modified particles. When the amount of the surfactant is not less than the lower limit, the modified particles can easily have excellent dispersibility. If the amount of the surfactant is less than the above upper limit, the properties (transport properties, etc.) of the modified particles are less likely to be impaired.

When the dispersion liquid contains an antifoaming agent, the amount of the antifoaming agent contained in the dispersion liquid varies depending on the amount of the modified particles, and the active ingredient is preferably 1% by mass or less with respect to the total mass of the dispersion liquid.

When the dispersion liquid contains the inorganic filler, the amount of the inorganic filler contained in the dispersion liquid is preferably 0.1 to 300 parts by mass, more preferably 1 to 200 parts by mass, still more preferably 3 to 150 parts by mass, particularly preferably 5 to 100 parts by mass, and most preferably 10 to 60 parts by mass, based on 100 parts by mass of the modified particles. The greater the amount of inorganic filler, the lower the coefficient of linear expansion (CTE) of the F layer, and the higher the dimensional stability of the F layer upon heating. Further, the dimensional change of the F layer in the heating process is small, and the forming stability is excellent.

The composition of the present invention comprises the above-mentioned modified particles and another polymer different from the F polymer, in which the modified particles are dispersed.

As other polymers, there may be mentioned: thermoplastic resin, thermosetting resin, photosensitive resin. In addition, as the other polymer, a non-fluororesin is preferable.

As the thermoplastic resin, there can be mentioned: polycarbonate, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyarylate, polycaprolactone, phenoxy resin, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyetherimide, semi-aromatic polyamide, polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyphenylene ether, polyphenylene sulfide, polytetrafluoroethylene, acrylonitrile-styrene-butadiene copolymer, polymethyl methacrylate, polypropylene, polyethylene, polybutadiene, butadiene-styrene copolymer, ethylene-propylene-diene rubber, styrene-butadiene block copolymer, butadiene-acrylonitrile copolymer, acrylic rubber, styrene-maleic anhydride copolymer, styrene-phenylmaleimide copolymer, poly (t-phenylene vinylene), poly (t-phenylene ether), poly (phenylene ether ketone), poly (phenylene ether ketone), poly (phenylene ether ketone), poly (ether ketone), poly (ether ketone), poly (ether-styrene-6-butadiene), poly (ether-styrene-butadiene), poly (ether-styrene-butadiene), poly (ether-styrene-butadiene) and poly (ether-styrene-butadiene), poly (ether-styrene-butadiene) block copolymer, butadiene), poly (ether-styrene-butadiene) copolymer, butadiene-styrene-butadiene) copolymer, butadiene-styrene-butadiene) copolymer, poly (styrene-butadiene) copolymer, butadiene-styrene-, Aromatic polyesters, polyamideimides, thermoplastic polyimides. The thermoplastic resin may be used alone in 1 kind, or in combination of 2 or more kinds.

The melting point of the thermoplastic resin is preferably 280 ℃ or higher. When the melting point of the thermoplastic resin is 280 ℃ or higher, expansion (foaming) of the F layer made of the composition due to heat when exposed to an atmosphere corresponding to solder reflow can be suppressed.

As the thermosetting resin, there can be mentioned: polyimide, epoxy resin, acrylic resin, phenolic resin, polyester resin, bismaleimide resin, polyolefin, polyphenylene oxide, and fluororesin. The thermosetting resin may be used alone in 1 kind, or in combination of 2 or more kinds.

As the thermosetting resin, polyimide, epoxy resin, acrylic resin, bismaleimide resin, polyphenylene ether are preferable, and at least 1 selected from polyimide and epoxy resin is more preferable. The resin composition containing a thermosetting resin is suitable for use in a printed wiring board.

The photosensitive resin may be a resin used for a resist material or the like, and specifically, an acrylic resin may be used. As the photosensitive resin, a thermosetting resin having photosensitivity may be used. Specific examples of the photosensitive resin include: thermosetting resins having a methacryloyl group, an acryloyl group, or the like introduced by reacting methacrylic acid, acrylic acid, or the like with a reactive group (epoxy group, or the like).

The composition may contain other polymers and other components than the modified particles as necessary.

As other components, there may be mentioned: liquid medium, inorganic filler with low dielectric constant and dielectric loss tangent, surfactant and defoaming agent.

The liquid medium, surfactant, defoaming agent, and inorganic filler may be the same as those listed for the dispersion. In addition, the liquid medium is preferably unreactive or poorly reactive with the F polymer and other polymers.

The amount of the modified particles contained in the composition is preferably 5 to 500 parts by mass, and more preferably 20 to 300 parts by mass, based on 100 parts by mass of the other polymer. In this case, the electrical properties of the composition and the mechanical strength of the F layer are improved.

When the composition is a liquid composition, the total amount of solid components contained in the liquid composition is preferably 30 to 80% by mass, and more preferably 45 to 65% by mass. In this case, the liquid composition has good coatability when forming the F layer.

When the composition contains a surfactant, the amount of the surfactant contained in the liquid composition is preferably 1 to 30 parts by mass, and more preferably 5 to 10 parts by mass, per 100 parts by mass of the modified particles. In this case, the dispersibility of the modified particles in the liquid composition and the properties (transmission properties and the like) of the F layer are easily balanced.

In the case where the liquid composition contains an antifoaming agent, the amount of the antifoaming agent contained in the liquid composition is preferably 1% by mass or less.

When the composition contains an inorganic filler, the amount of the inorganic filler contained in the composition is preferably 0.1 to 100 parts by mass, and more preferably 0.1 to 60 parts by mass, relative to 100 parts by mass of the other polymer.

As the composition of the present invention, there may be mentioned: (i) a method of mixing and melt-kneading a thermoplastic resin as another polymer with the modified particles; (ii) a method of dispersing the modified particles in a varnish containing a thermosetting resin as another polymer; (iii) a method of mixing a varnish containing a thermosetting resin as another polymer with the modified particle-containing dispersion liquid.

The composition of the present invention may be used for the F layer in the following laminate. Other uses include: interlayer insulating film, solder resist, and base material film of cover film.

As described above, the composition contains modified particles having a D50 of 0.01 to 100 μm, that is, modified particles having a sufficiently small average particle diameter. Therefore, a thin F layer can be formed. Further, the modified particles have good dispersibility in other polymers.

The laminate of the present invention has a substrate and an F layer provided on the surface of the substrate. That is, the laminate may have a structure in which the F layer is laminated only on one surface of the base material, or may have a structure in which the F layer is laminated on both surfaces of the base material.

The latter laminate is preferable from the viewpoint of suppressing warpage of the laminate or from the viewpoint of obtaining a double-sided metal laminated plate excellent in electrical reliability. In this case, the composition and thickness of the 2F layers may be the same or different. From the viewpoint of suppressing warpage of the laminate, the compositions and thicknesses of the 2 resin layers are preferably the same.

Layer F is comprised of the composition of the present invention. Thus, the F layer comprises the modified particle of the present invention. Therefore, the above-described effects are exhibited.

When the laminate is used for a printed wiring board, the thickness of the F layer is preferably 0.5 to 300. mu.m, more preferably 3 to 200. mu.m, and still more preferably 10 to 150. mu.m, from the viewpoint of the balance between the reduction in thickness and the electrical properties.

The relative dielectric constant of the F layer is preferably 2 to 3.5, more preferably 2 to 3. In this case, the laminate can be suitably used for a printed wiring board or the like which is required to have a low dielectric constant, and the F layer is excellent in both electrical properties and adhesiveness.

Examples of the base material include: a heat-resistant resin film, a fiber-reinforced resin sheet, a laminated film having a heat-resistant resin film layer, and a laminated film having a fiber-reinforced resin layer. In the case where the laminate is used as a substrate of a flexible printed wiring board, the substrate is preferably a heat-resistant resin film.

The heat-resistant resin film is a film containing 1 or more kinds of heat-resistant resins, and may be a single-layer film or a multilayer film.

Examples of the heat-resistant resin include: polyimide (aromatic polyimide, etc.), polyarylate, polysulfone, polyarylsulfone (polyethersulfone, etc.), aromatic polyamide, aromatic polyetheramide, polyphenylene sulfide, polyaryletherketone, polyamideimide, liquid crystal polyester.

As the heat-resistant resin film, a polyimide film is preferable. The polyimide film is a film made of polyimide. The polyimide film may contain other components than polyimide as necessary.

When the laminate is used for a printed wiring board, the thickness of the heat-resistant resin film is preferably 0.5 to 100 μm, more preferably 1 to 50 μm, and still more preferably 3 to 25 μm, from the viewpoint of balance between the reduction in thickness and the mechanical strength.

The heat-resistant resin film can be produced by a method of molding a heat-resistant resin or a heat-resistant resin-containing resin composition into a film by a known molding method (e.g., casting (キャスト), extrusion, or inflation). The heat-resistant resin film may be a commercially available one.

The surface of the heat-resistant resin film may be subjected to surface treatment. Examples of the surface treatment method include: corona discharge treatment and plasma treatment.

The laminate of the present invention can also be used as a metal laminate having a metal layer as a base material. In this case, the metal laminate may further have a substrate provided on the surface of the F layer opposite to the metal layer.

That is, the layer structure of the metal laminated plate includes: metal layer/F layer, metal layer/F layer/metal layer, substrate/F layer/metal layer, metal layer/F layer/substrate/F layer/metal layer. Here, "metal layer/F layer" indicates a structure in which a metal layer and an F layer are stacked in this order, and the same applies to other layer structures.

Examples of the metal constituting the metal layer include: copper, copper alloys, stainless steel, nickel alloys (also 42 alloys), aluminum alloys.

Examples of the metal layer include: a layer made of metal foil, and a metal vapor-deposited film.

Examples of the metal foil include: rolled copper foil, electrolytic copper foil. A rust-proof layer (oxide film such as chromate film) or a heat-resistant layer may be formed on the surface of the metal foil. In addition, in order to improve adhesion to the F layer, a coupling agent treatment or the like may be performed on the surface of the metal foil.

The thickness of the metal layer may be any thickness that can sufficiently function in the use of the metal laminate.

As the laminate (metal laminate), there can be mentioned: (i) a method in which a liquid composition of the present invention is applied to the surface of a substrate (metal foil), and the liquid medium is removed by drying, and if necessary, another polymer is cured; (ii) a method of pressure-bonding the F layer (resin film) and the base material (metal foil) by a hot press method or the like; (iii) a metal is deposited on the surface of the F layer by a method such as vacuum deposition, sputtering, or ion plating.

The metal laminate may be used as a printed wiring board by etching a metal layer to form a patterned circuit (having a predetermined pattern shape).

In the printed wiring board, unevenness at the interface between the patterned circuit and the F layer is suppressed. As a result, the patterned circuit and the F layer have excellent adhesion and excellent transmission performance.

In the printed wiring board, an interlayer insulating film and a patterned circuit may be stacked in this order on the patterned circuit. An interlayer insulating film may be formed using the composition of the present invention.

In the printed wiring board, a solder resist may be laminated on the patterned circuit. A solder resist can be formed using the composition of the present invention.

The surface of the printed wiring board may be laminated with a cover film. The cover film is composed of a base film and a pressure-sensitive adhesive layer formed on the surface of the base film. The base film of the cover film may be formed using the composition of the present invention.

In the printed wiring board, an interlayer insulating film (adhesive layer) using the composition of the present invention and a polyimide film as a cover film may be sequentially stacked on a patterned circuit.

Although the method for producing modified particles, dispersion liquid, composition, and laminate of the present invention have been described above, the present invention is not limited to the configuration of the above embodiment.

For example, in the configuration of the above embodiment, other arbitrary configurations may be added to the modified particles, the dispersion liquid, the composition, and the laminate of the present invention, and these may be replaced with arbitrary configurations that exhibit the same function.

In the configuration of the above embodiment, other arbitrary steps may be added to the method for producing modified particles of the present invention, or may be replaced with arbitrary steps that perform the same function.

Examples

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

The melting point and MFR of the F polymer and D50 and D90 of the masterbatch were determined as follows.

The melting point of the F polymer was measured by using a differential scanning calorimeter (DSC-7020) manufactured by Seiko instruments K.K. (セイコーインスツル Co.). The temperature rising rate of the polymer F was set to 10 ℃ per minute.

The MFR of the F polymer was determined by measuring the mass (g) of the F polymer flowing out from a nozzle having a diameter of 2mm and a length of 8mm in 10 minutes (unit time) at 372 ℃ under a load of 49N using a melt index apparatus manufactured by Tehno 7 K.K.K..

The particle size distribution was measured by dispersing particles in water using a laser diffraction scattering particle size distribution measuring device (horiba, horiba corporation, LA-920 measuring instrument), and the D50 and D90 of the master batch were calculated.

Example 1 production of mother particles

[ examples 1-1]

A raw material particle A1 composed of F polymer 1 was produced by the procedure described in paragraph [0123] of International publication No. 2016/017801 using NAH, TFE and PPVE.

The proportions (mol%) of the NAH unit, TFE unit, and PPVE unit contained in the F polymer 1 were 0.1, 97.9, and 2.0 in this order. The melting point of the F polymer 1 was 300 ℃ and the MFR was 17.6g/10 min.

The raw material particles A1 were pulverized once using a jet mill (model STJ-400 single rail jet mill manufactured by QINGXINGKOKU Co., Ltd. (セイシン, Enterprise )) under a pulverization pressure of 0.65MPa and a processing speed of 10kg/hr to obtain pulverized particles (D50: 2.9 μm and D90: 10.0. mu.m). The pulverized particles were again subjected to jet milling, and the resultant was subjected to secondary pulverization under a pulverization pressure of 0.65MPa and a processing speed of 10kg/hr to obtain mother particles 1 (D50: 1.7 μm, D90: 3.9 μm).

[ examples 1-2]

The raw material particles A2 composed of polytetrafluoroethylene (PTFE; model L169J, manufactured by AGC Co., Ltd.) were subjected to primary pulverization and secondary pulverization using a jet mill (model FS-4 single rail jet mill, manufactured by fresh industries, Ltd. (セイシン corporation, )) under a pulverization pressure of 0.5MPa and a processing speed of 1kg/hr to obtain mother particles 2 (D50: 3.0 μm, D90: 8.5 μm).

Examples 1 to 3 (comparative examples)

The raw material particles A1 were subjected to primary pulverization and secondary pulverization using a jet mill (model FS-4 single-rail jet mill manufactured by freshening corporation, Inc. (セイシン, Inc.; )) under a pulverization pressure of 0.5MPa and a processing speed of 3kg/hr to obtain a master batch 3 (D50: 6.5 μm, D90: 11.5 μm).

Example 2 production of modified particles

[ example 2-1]

The mother particles 1 were subjected to plasma treatment using a plasma treatment apparatus (PDC 210 manufactured by yamat corporation) to obtain modified particles 1. In addition, the conditions of the plasma treatment were: the RF output power was 300W, the inter-electrode gap was 20cm, the introduced gas was argon, and the introduced gas flow rate was 20cm³Per minute, pressure 13Pa, treatment time 30 minutes.

[ examples 2-2 to 2-8]

Modified particles 2 to 8 were obtained in the same manner as in example 2-1, except that the type of the base particles and the type of the introduced gas used for the plasma treatment were changed as shown in table 1.

[ Table 1]

In addition, 1Ar (50 vol%) and O₂(50 vol%) of mixed gas

Example 3 evaluation of dispersibility and zeta potential of modified particles

The dispersibility and zeta potential of the modified particles were evaluated by the following methods, and the results are shown in table 2.

< dispersibility >

After a dispersion liquid in which 100g of the modified particles were dispersed in 100g of water was left at 25 ℃ for 30 days, the dispersion liquid was allowed to pass through JIS Z8801-1: a 200-mesh screen of 2006, and the residue remaining on the screen was collected. The quality of the recovered residue was measured and evaluated according to the following criteria.

1: the mass of the residue was greater than 5 g.

2: the mass of the residue was greater than 3g and below 5 g.

3: the mass of the residue was below 3 g.

Zeta potential >

The zeta potential of the master batch and the modified particles immediately after the plasma treatment and after 30 days at 25 ℃ was measured using a zeta potential measuring device (ELS-8000 manufactured by Otsuka Denshi Co., Ltd.)Determining Y₀The value of/X and Y₃₀/Y₀The results are shown in Table 2.

In addition, Y₀The value of/X is the ratio of the zeta potential value of the modified particles immediately after the plasma treatment to the zeta potential value of the master batch, and Y₃₀/Y₀The value is a ratio of a zeta potential value of the modified particle after 30 days from the plasma treatment to a zeta potential value of the modified particle immediately after the plasma treatment.

[ Table 2]

Example 3 production of laminate

[ example 3-1]

Using the modified particles 1 immediately after the surface treatment and the modified particles 1 after 14 days from the surface treatment, a laminate was produced as follows.

First, 300g of modified particles 1, 30g of a nonionic surfactant (Ftergent 710FL available from Nines corporation, ネオス) and 330g of N-methyl-2-pyrrolidone were put into a horizontal ball mill pot, and then zirconium beads having a diameter of 15mm were packed, followed by dispersion treatment to obtain a dispersion 1. This dispersion 1 was allowed to stand for 1 day, and then stirred for 5 minutes with a laboratory stirrer (LT-500 manufactured by Yamadoto science Co., Ltd. (ヤマト science Co., Ltd.).

Subsequently, a thermosetting modified polyimide varnish (manufactured by PI institute, ltd., ピーアイ, and a solvent: N-methylpyrrolidone, solid content: 15 mass%) and a dispersion 1 were mixed so that the mass ratio of the thermosetting modified polyimide to the F polymer 1 was 80: 20 to obtain a liquid composition 1.

The liquid composition 1 was coated on the surface of a copper foil having a thickness of 12 μm, dried at 150 ℃ for 10 minutes under a nitrogen atmosphere, and after heating at 260 ℃ for 10 minutes, cooled to 25 ℃ to obtain a laminate (single-sided copper-clad laminate) having a polymer layer containing the F polymer 1 having a thickness of 10 μm.

[ examples 3-2 to 3-10]

Laminates were produced in the same manner as in example 3-1, except that modified particles 2 to 8 and mother particles 1 to 2 were used instead of modified particle 1. In addition, in the production example of the laminate using the base particles, the base particles immediately after production are used.

The surface smoothness of the polymer layer of the obtained laminate was evaluated by the following method, and the results are shown in table 3.

< surface smoothness >

The polymer layer surface of the laminate was visually observed and evaluated according to the following criteria.

1: unevenness is formed on the surface due to uneven streaks and coarse particles, and the surface is matt.

2: the surface roughness caused by the coarse particles results in a mat surface.

3: the surface roughness caused by coarse particles was slightly visible, but glossy.

4: the surface was flat and glossy.

[ Table 3]

The modified particle of the present invention is used for a resin layer in contact with a patterned circuit in a printed wiring board, and is useful for improving the transmission performance of the printed wiring board. The dispersion and the composition of the present invention can be used for the production of a resin layer provided in a film, an impregnated material (prepreg, etc.), etc., and also for the production of a molded article for applications requiring releasability, electrical properties, water-and oil-repellency, chemical resistance, weather resistance, heat resistance, smoothness, abrasion resistance, etc. The resin layer formed from the composition is useful as an antenna part, a printed circuit board, an airplane part, an automobile part, a sports equipment, a food industry product, a paint, a cosmetic, and the like, and specifically, is useful as an insulating layer of a power module, an electric wire coating material (an airplane electric wire and the like), an electrically insulating tape, an insulating tape for oil drilling, a material for a printed circuit board, an electrode adhesive (a lithium secondary battery, a fuel battery and the like), a copying roll, furniture, an automobile instrument panel, a cover for a household appliance, a sliding member (a load bearing, a sliding shaft, a valve, a bearing, a gear, a cam, a belt conveyor, a food conveyor belt and the like), a tool (a shovel, a file, a awl, a saw and the like), a boiler, a hopper, a pipe, a mold oven, a baking mold, a chute, a file, a toilet, a container covering material, and the like.

The entire contents of the specification, claims and abstract of japanese patent application No. 2018-228362 filed on 12/5/2018 are incorporated herein as disclosure of the present invention.

Claims

1. A method for producing modified particles, which comprises subjecting a tetrafluoroethylene polymer base particle having a cumulative 50% by volume diameter of 0.01 to 100 [ mu ] m to surface treatment to obtain modified particles obtained by introducing a polar group into the base particle.

2. The manufacturing method according to claim 1, wherein the surface treatment is a plasma treatment or a corona treatment.

3. The production method according to claim 2, wherein the master batch is subjected to plasma treatment in an atmosphere containing at least 1 kind selected from the group consisting of argon, helium, and oxygen.

4. The production process according to any one of claims 1 to 3, wherein the tetrafluoroethylene-based polymer contains 99.5 mol% or more of a tetrafluoroethylene-based unit with respect to all units contained in the polymer.

5. The production process according to any one of claims 1 to 3, wherein the tetrafluoroethylene-based polymer contains more than 0.5 mol% of units based on a comonomer other than tetrafluoroethylene, based on all units contained in the polymer.

6. The production process according to any one of claims 1 to 5, wherein the tetrafluoroethylene-based polymer has at least 1 functional group selected from a carbonyl group-containing group, a hydroxyl group, an epoxy group, an oxetanyl group, an amino group, a cyano group and an isocyanate group.

7. The production process according to any one of claims 1 to 6, wherein the tetrafluoroethylene polymer is a hot-melt polymer having a melting point of 260 to 320 ℃.

8. Modified particles obtained by surface-treating tetrafluoroethylene polymer base particles having a cumulative 50% by volume of 0.01 to 100 μm diameter,

9. The modified particle according to claim 8, wherein the tetrafluoroethylene-based polymer has at least 1 functional group selected from a carbonyl group-containing group, a hydroxyl group, an epoxy group, an oxetanyl group, an amino group, a cyano group and an isocyanate group.

10. The modified particle according to claim 8 or 9, wherein a zeta potential of the mother particle is X, and a zeta potential of the modified particle immediately after the surface treatment is Y₀When, Y₀The value of/X is 1.3 or more.

11. The modified particle according to any one of claims 8 to 10, wherein a zeta potential of the modified particle immediately after the surface treatment is represented by Y₀And zeta potential of the modified particles after 30 days at 25 ℃ from the completion of the surface treatment was recorded as Y₃₀When, Y₃₀/Y₀Is 0.8 or more.

12. The modified particle as claimed in any one of claims 8 to 11, wherein 100g of the modified particle is dispersed in 100g of water to prepare a dispersion, and the dispersion after 30 days at 25 ℃ is passed through a JIS Z8801-1: in the case of a 200 mesh screen of 2006, the amount of residue remaining on the screen is 5g or less.

13. A dispersion comprising the modified particle of any one of claims 8 to 12 and a liquid medium in which the modified particle is dispersed.

14. A composition comprising the modified particle as claimed in any one of claims 8 to 12 and another polymer different from the tetrafluoroethylene-based polymer, the modified particle being dispersed in the other polymer.

15. A laminate comprising a substrate and a layer comprising the modified particle according to any one of claims 8 to 12 provided on the surface of the substrate.