WO2022019223A1 - Dispersion, composite particles, and method for producing composite particles - Google Patents

Abstract

[Problem] To provide: a dispersion which contains composite particles of a tetrafluoroethylene-based polymer and has excellent dispersion stability; and composite particles which contain a predetermined tetrafluoroethylene-based polymer and silica, have excellent dispersion stability in a dispersion medium, and have desirable physical properties such as high polarity. [Solution] This dispersion comprises: composite particles that contain an inorganic substance and a tetrafluoroethylene-based polymer having a melting temperature of 260-320ºC; an aromatic polymer; and a liquid dispersion medium, wherein the composite particles are dispersed in the liquid dispersion medium, and the dispersion has a viscosity at 25ºC of 1,000-100,000 mPa∙s.

Description

Dispersion liquid, composite particles and method for producing composite particles

The present invention relates to a dispersion containing composite particles of a tetrafluoroethylene polymer.
The present invention also relates to composite particles containing a predetermined tetrafluoroethylene polymer and silica, and a method for producing the same.

Tetrafluoroethylene-based polymers such as polytetrafluoroethylene (PTFE) have excellent physical properties such as electrical properties, water and oil repellency, chemical resistance, and heat resistance, and the particles are printed corresponding to frequencies in the high frequency band. In recent years, it has attracted particular attention as a substrate material.
Patent Document 1 discloses a composition containing silica-coated fluororesin particles and a resin component from the viewpoint of improving the flow characteristics of a printed circuit board material and improving its electrical characteristics, fine wiring embedding property, heat resistance and developability. Has been done.
As the composite particles of silica and the tetrafluoroethylene polymer, the aspects of Patent Document 2 and Patent Document 3 are known.

International Publication No. 2017/135168 Japanese Unexamined Patent Publication No. 2016-124729 International Publication No. 2018/21279

However, according to the studies by the present inventors, the resin composition described in Patent Document 1 does not have sufficient uniformity and dispersion stability when dissolved or dispersed in a liquid, and there is a problem in handling the resin composition. .. Further, in the molded product obtained from the dispersion liquid, the uniformity of the component distribution tends to decrease, and the appearance of the molded product tends to have a rough surface. Further, the epoxy resin, maleimide compound, cyanate ester compound, benzoxazine compound and the like specifically disclosed in Patent Document 1 as usable resin components can be obtained and the processability of the composition with the tetrafluoroethylene polymer can be obtained. There is still room for improvement in the heat resistance of the molded product.
On the other hand, the tetrafluoroethylene polymer has extremely low polarity and low affinity with other components, so that it is highly difficult to interact with silica. Therefore, it is difficult for the composite particles of Patent Document 2 and Patent Document 3 to take in a sufficient amount of silica.
Further, since the composite particles of the above documents have low interaction between silica and the tetrafluoroethylene-based polymer, the stability of the composite particles themselves is not sufficient, and silica is likely to fall off from the composite particles. Therefore, it is necessary to secure the interaction between silica and the tetrafluoroethylene polymer, and the range of selection of silica (the amount of hydroxyl groups of silica, etc.) is likely to be restricted.
Further, this restriction limits the usage mode of the composite particles of the above documents. For example, it is difficult to increase the affinity of the composite particles for the liquid medium, and when preparing a liquid composition in which the composite particles are dispersed, foaming is intense and it is difficult to secure the dispersion stability.

As a result of diligent studies, the present inventors include composite particles containing a predetermined tetrafluoroethylene-based polymer and an inorganic substance, an aromatic polymer, and a liquid dispersion medium, and the composite particles are dispersed in the liquid dispersion medium. It was found that the dispersion liquid in the specific viscosity range was excellent in dispersion stability. Further, it was found that the molded product obtained from such a dispersion liquid is dense and is particularly excellent in low linear expansion coefficient and the like.
The present inventors also include composite particles containing a predetermined tetrafluoroethylene-based polymer and an inorganic substance, and a liquid dispersion medium, wherein the liquid dispersion medium contains two types of liquid dispersion media having different boiling points, and the above 2 The dispersion liquid in which various liquid dispersion media are related to form an azeotropic mixture is excellent in dispersion stability, and the molded product obtained from the dispersion liquid is dense, and has characteristics such as low linear expansion coefficient including appearance. It turned out to be excellent.
Furthermore, the present inventors have found that the above-mentioned problems can be solved by controlling the atomic ratio of fluorine and silicon on the surface of the obtained composite particles by using a predetermined tetrafluoroethylene polymer.
An object of the present invention is to provide a dispersion liquid having excellent dispersion stability. Further, an object of the present invention is to provide a dispersion liquid which is dense and can obtain a molded product having excellent characteristics such as an appearance and a low coefficient of linear expansion. Further, an object of the present invention is to provide composite particles having excellent dispersion stability in a dispersion medium and having desired physical properties such as high polarity, and a method for producing the same.

The present invention has the following aspects.
<1> A composite particle containing a tetrafluoroethylene-based polymer having a melting temperature of 260 to 320 ° C. and an inorganic substance, an aromatic polymer, and a liquid dispersion medium are contained, and the composite particle is dispersed in the liquid dispersion medium. A dispersion having a viscosity of 1000 to 100,000 mPa · s at 25 ° C.
<2> The tetrafluoroethylene-based polymer contains a unit based on perfluoro (alkyl vinyl ether) and has a polar functional group, or a tetrafluoroethylene-based polymer having a polar functional group, or a unit based on perfluoro (alkyl vinyl ether) for all units. A dispersion of <1>, which is a tetrafluoroethylene-based polymer containing 0.0 to 5.0 mol% and having no polar functional group.
<3> The dispersion liquid of <1> or <2>, wherein the inorganic substance is silica.
<4> The dispersion liquid according to any one of <1> to <3>, wherein the content of the aromatic polymer is less than the content of the composite particles.
<5> The aromatic polymer is at least one selected from the group consisting of aromatic polyimide, aromatic polyamide, aromatic polyamideimide, polyphenylene ether, liquid crystal polyester, and aromatic maleimide, <1> to <. 4> Any dispersion.
<6> A dispersion liquid containing a composite particle containing a tetrafluoroethylene-based polymer having a melting temperature of 260 to 320 ° C. and an inorganic substance, and a liquid dispersion medium, in which the composite particle is dispersed in the liquid dispersion medium. , A dispersion liquid in which the liquid dispersion medium contains two types of liquid dispersion media having different boiling points, and the two types of liquid dispersion media form a co-boiling mixture.
<7> The tetrafluoroethylene-based polymer contains a unit based on perfluoro (alkyl vinyl ether) and has a polar functional group, or a tetrafluoroethylene-based polymer having a polar functional group, or a unit based on perfluoro (alkyl vinyl ether) for all units. A dispersion of <6>, which is a tetrafluoroethylene-based polymer containing 0.0 to 5.0 mol% and having no polar functional group.
<8> The mixing amount ratio of the dispersion medium having a high boiling point in the two types of liquid dispersion media having different boiling points is the composition ratio of the dispersion medium having a high boiling point in the azeotropic mixture of the two types of liquid dispersion media. A dispersion of <6> or <7>, which is greater than (mass ratio).
<9> The dispersion liquid according to any one of <6> to <8>, wherein at least one of the two types of liquid dispersion media having different boiling points constituting the liquid dispersion medium is water, an alcohol, or an amide.
<10> A tetrafluoroethylene polymer having a melting temperature of 260 to 320 ° C. and containing 1 to 5 mol% of units based on perfluoro (alkyl vinyl ether) with respect to all units and silica are contained, and X-ray photoelectrons are contained. A composite particle in which the amount of silicon atoms is 1 or more with respect to the amount of fluorine atoms on the surface measured by spectroscopy.
<11> Composite particles of <10> having an average particle diameter of 2 μm or more and 10 μm or less.
<12> Composite particles of <10> or <11>, wherein the silica is 15 to 85 parts by mass with respect to 100 parts by mass of the tetrafluoroethylene polymer.
<13> The composite particle according to any one of <10> to <12>, which has the tetrafluoroethylene polymer as a core and the silica on the surface of the core.
<14> The composite particle according to any one of <10> to <13>, wherein the tetrafluoroethylene polymer is a tetrafluoroethylene polymer having a polar functional group.
<15> The particles of the tetrafluoroethylene-based polymer and the silica are collided with each other at a temperature equal to or higher than the melting temperature of the tetrafluoroethylene-based polymer and in a suspended state to obtain the composite particles, <10> to <14>. A method for producing any of the composite particles.

According to the present invention, a dispersion liquid of a tetrafluoroethylene-based polymer having excellent dispersion stability can be obtained.
The molded product formed from the dispersion liquid of the present invention is dense and has excellent physical properties such as appearance, heat resistance, electrical characteristics, and low linear expansion property, and is useful as a constituent material of a printed circuit board, for example.
According to the present invention, there are provided composite particles having excellent dispersion stability in a dispersion medium and having desired physical properties such as high polarity, and a method for producing the same. The dispersion liquid containing such composite particles has an excellent appearance of the coating film when applied to the substrate. Further, from such a dispersion liquid, a laminate and a film having excellent properties (electrical properties, low line expandability, etc.) based on a tetrafluoroethylene polymer and an inorganic substance, particularly silica, can be obtained.

The following terms have the following meanings.
The "average particle size (D50)" is a volume-based cumulative 50% diameter of an object (particle) obtained by a laser diffraction / scattering method. That is, the particle size distribution of the object is measured by the laser diffraction / scattering method, the cumulative curve is obtained with the total volume of the group of particles of the object as 100%, and the particles at the point where the cumulative volume is 50% on the cumulative curve. The diameter.
“D90” is the volume-based cumulative 90% diameter of the object, which is similarly measured.
The objects (particles) D50 and D90 are analyzed by a laser diffraction / scattering method using a laser diffraction / scattering type particle size distribution measuring device (LA-920 measuring instrument manufactured by HORIBA, Ltd.) by dispersing the particles in water. Is required.
The "melting temperature (melting point)" is the temperature corresponding to the maximum value of the melting peak of the polymer measured by the differential scanning calorimetry (DSC) method.
The "glass transition point (Tg)" is a value measured by analyzing a polymer by a dynamic viscoelasticity measurement (DMA) method.
The "viscosity" is a value obtained by measuring an object (dispersion liquid or liquid composition) at 25 ° C. and a rotation speed of 30 rpm using a B-type viscometer. The measurement is repeated 3 times, and the average value of the measured values for 3 times is used.
_{The "thixotropic ratio" is a viscosity η 1} obtained by measuring an object (dispersion liquid or liquid composition) under the condition of a rotation speed of 30 rpm, _{and a viscosity η 2 obtained by measuring the viscosity η 2 under} the condition of a rotation speed of 60 rpm. It is a value calculated by dividing by (η ₁ / η ₂ ). Each viscosity measurement is repeated 3 times and calculated by the average value of the measured values for 3 times.
The "specific surface area" is a value calculated by measuring particles by a gas adsorption (constant volume method) BET multipoint method, and is obtained by using NOVA4200e (manufactured by Quantachrome Instruments).
The "unit" in the polymer may be an atomic group formed directly from the monomer, or may be an atomic group in which a part of the structure is converted by treating the obtained polymer by a predetermined method. The unit based on the monomer A contained in the polymer is also simply referred to as "monomer A unit".

The first dispersion liquid of the present invention (hereinafter, also referred to as “the present dispersion liquid A”) is a tetrafluoroethylene-based polymer (hereinafter, also referred to as “F polymer”) having a melting temperature of 260 to 320 ° C. It contains composite particles containing an inorganic substance (hereinafter, also referred to as “main particles”), an aromatic polymer, and a liquid dispersion medium.
The present dispersion A is a dispersion in which the particles are dispersed in a liquid dispersion medium and has a viscosity at 25 ° C. of 1000 to 100,000 mPa · s.

The present dispersion A has excellent dispersion stability. The reason why the dispersion stability of the dispersion liquid A is improved, and the correlation and action mechanism between the composition of the particles contained in the dispersion liquid A and the dispersion stability are not necessarily clear, but are estimated as follows, for example. is doing.
The particles containing an inorganic substance have significantly improved wettability. When the particles having improved wettability are added to a liquid dispersion medium, they tend to form a smooth suspension in which the particles tend to settle, rather than a dispersion liquid.
On the other hand, the particles contain an F polymer and an inorganic substance. Compared to non-heat-meltable tetrafluoroethylene polymers, F-polymers are not only superior in shape stability such as fibril resistance, but also have a high degree of freedom in which restrictions on molecular motion are relaxed at the single-molecule level. Has a formation. Since such an F polymer tends to form microspherulites at the molecular aggregate level, fine uneven structures are likely to be formed on the surface thereof, and the surface area is likely to be large. Therefore, it is considered that the molecular aggregate of the F polymer can physically adhere closely to the inorganic substance to form the present particles while maintaining its stable shape without damaging its shape. Further, although the F polymer has low surface energy and low dispersion stability, the particles in which the F polymer and the inorganic substance are fused are more likely to interact with other particles and the liquid dispersion medium than the F polymer, and the dispersion stability is high. It is considered to be excellent in sex.
Furthermore, by coexisting an aromatic polymer, which is hydrophobic like the F polymer and has a high affinity with the F polymer, in the liquid dispersion medium, the dispersion stability is further improved, and the viscosity, thixotropic ratio, sedimentation rate, etc. are increased. It is considered that the present dispersion A, which has excellent physical properties and is easy to handle, can be obtained. As a result, the dispersion liquid A has the physical properties of the F polymer, the physical properties of the inorganic substance, and the physical properties of the aromatic polymer to a high degree, and has excellent component uniformity, high density (small void ratio), and excellent electrical characteristics. It is probable that the molded product was formed.

In the present invention, the F polymer constituting the particles is a heat-meltable polymer containing a unit (TFE unit) based on tetrafluoroethylene (TFE). The melting temperature of the F polymer is 260 to 320 ° C., preferably 280 to 320 ° C., more preferably 285 to 320 ° C. In such a case, the heat resistance of the molded product formed from the present dispersion A tends to be excellent.
Here, the heat-meltable polymer means a polymer having a temperature at which the melt flow rate is 1 to 1000 g / 10 minutes under the condition of a load of 49 N.
The glass transition point of the F polymer is preferably 75 to 125 ° C, more preferably 80 to 100 ° C.
Examples of the F polymer include polymers (PFA) containing TFE units and units based on perfluoro (alkyl vinyl ether) (PAVE) (PAVE units), and polymers (FEP) containing units based on TFE units and hexafluoropropene (HFP). Therefore, it is preferably PFA. As the PAVE, CF ₂ = CFOCF ₃ , CF ₂ = CFOCF ₂ CF ₃ and CF ₂ = CFOCF ₂ CF ₂ CF ₃ (PPVE) are preferable, and PPVE is more preferable.
The melt viscosity of the F polymer ^{is preferably 1 × 10 2} to 1 × 10 ⁶ Pa · s at 380 ° C., more preferably 1 × 10 ³ to 1 × 10 ⁶ Pa · s.
If the melting temperature, the glass transition point, or the melting viscosity of the F polymer is within such a range, the above-mentioned mechanism of action is likely to be enhanced.

Suitable embodiments of the F polymer include a polymer (1) containing TFE units and PAVE units and having a polar functional group, or TFE units and PAVE units, with PAVE units 2.0 to 2.0 for all monomer units. The polymer (2) containing 5.0 mol% and having no polar functional group is preferable, and the polymer (1) is more preferable.
Not only are the particles of these F polymers excellent in dispersion stability, but they are also likely to be more densely and uniformly distributed in a molded product such as a polymer layer obtained from the dispersion liquid A. Further, when the dispersion liquid containing these F polymers is applied to a substrate to form a polymer layer, microspherulites are likely to be formed in the polymer layer, and adhesion with other components is likely to be enhanced. As a result, it is easier to obtain a molded product having excellent various physical characteristics such as electrical characteristics.

The polar functional group contained in the polymer (1) may be contained in the unit contained in the polymer, may be contained in the terminal group of the polymer main chain, and is preferably contained in the unit contained in the polymer. Examples of the latter polymer include polymers having a polar functional group as a terminal group derived from a polymerization initiator, a chain transfer agent, radiation treatment, etc., and a polymer having a polar functional group prepared by plasma treatment or ionization line treatment. Be done.

The number of polar functional groups in the polymer (1) is preferably 10 to 5000, more preferably 100 to 3000, per ^{1 × 10 6 carbon atoms in the main chain.} The number of oxygen-containing polar groups in the polymer (1) can be quantified by the composition of the polymer or the method described in International Publication No. 2020/145133.
As the polar functional group, a hydroxyl group-containing group, a carbonyl group-containing group and a phosphono group-containing group are preferable, and a hydroxyl group-containing group and a carbonyl group-containing group are more preferable, and a carbonyl group is more preferable from the viewpoint of easily enhancing physical properties such as dispersibility of the particles. The containing group is more preferable.

As the hydroxyl group-containing group, an alcoholic hydroxyl group-containing group is preferable, and —CF ₂ CH ₂ OH, —C (CF ₃ ) ₂ OH and 1,2-glycol group (—CH (OH) CH ₂ OH) are more preferable.
Examples of the carbonyl group-containing group include a carboxyl group, an alkoxycarbonyl group, an amide group, an isocyanate group, a carbamate group (-OC (O) NH ₂ ), an acid anhydride residue (-C (O) OC (O)-), and the like. An imide residue (-C (O) NHC (O)-etc.) and a carbonate group (-OC (O) O-) are preferable, and an acid anhydride residue is more preferable.

The polymer (1) is preferably a polymer containing a TFE unit, a PAVE unit and a unit based on a monomer having a polar functional group, and 90 to 99 mol% of these units are used in this order with respect to all the units, 0. More preferably, the polymer contains 5.5 to 9.97 mol% and 0.01 to 3 mol%. The presence of the polar functional group is preferable from the viewpoint of further improving the affinity and adhesion with the inorganic substance.
As the monomer having a polar functional group, anhydrous itaconic acid, anhydrous citraconic acid or 5-norbornen-2,3-dicarboxylic acid anhydride (also known as anhydrous hymic acid; hereinafter also referred to as “NAH”) is preferable.
Specific examples of the polymer (1) include the polymers described in International Publication No. 2018/16644.

The polymer (2) consists of only TFE units and PAVE units, and contains 95.0 to 98.0 mol% of TFE units and 2.0 to 5.0 mol% of PAVE units with respect to all the units. preferable.
The content of PAVE units in the polymer (2) is preferably 2.1 mol% or more, more preferably 2.2 mol% or more, based on all the units.
Such a polymer has a higher degree of freedom in molecular conformation, and the above-mentioned mechanism of action is likely to be enhanced.
The fact that the polymer (2) does not have polar functional groups means that the number of polar functional groups possessed by the polymer is less than 500 per ^{1 × 10 6 carbon atoms constituting the polymer main chain.} Means that The number of the polar functional groups is preferably 100 or less, more preferably less than 50. The lower limit of the number of polar functional groups is usually 0.

The polymer (2) may be produced by using a polymerization initiator, a chain transfer agent or the like that does not generate a polar functional group as a terminal group of the polymer chain, and is derived from a polymer having a polar functional group (polymerization initiator). A polymer having a polar functional group at the terminal group of the polymer chain, etc.) may be fluorinated to be produced.
Examples of the fluorination treatment method include a method using fluorine gas (see JP-A-2019-194314).

In the present invention, the shape of the inorganic substance constituting the particles is preferably particles. Examples of the inorganic substance include particles composed of oxides, nitrides, simple metals, alloys and carbon, and silicates (silicon oxide (silica), wollastonite, talc, mica) and metal oxides (berylium oxide). , Cerium oxide, aluminum oxide, soda alumina, magnesium oxide, zinc oxide, titanium oxide, etc.), boron nitride and magnesium metasilicate (steatite) particles are preferable, and an element selected from aluminum, magnesium, silicon, titanium and zinc. Particles of an inorganic oxide containing at least one of the above are more preferable, particles of silica, titanium oxide, zinc oxide, steatite and boron nitride are more preferable, and particles of silica are particularly preferable. Further, the inorganic substance may be ceramics. As the inorganic substance, one kind may be used, or two or more kinds may be mixed and used. When two or more kinds of inorganic substances are mixed and used, two kinds of silica particles may be mixed and used, or silica particles and metal oxide particles may be mixed and used.

The average particle size (D50) of the inorganic particles is preferably 20 μm or less, more preferably 5 μm or less. The average particle size is preferably 0.001 μm or more, more preferably 0.01 μm or more.
The specific surface area of the inorganic particles (BET method) is preferably 1 ~ ^20m 2 / g, more preferably 5 ~ ^8m 2 / g. In this case, the interaction between the inorganic substance and the F polymer is likely to be enhanced. Further, in the molded product (polymer layer or the like), the inorganic substance and the F polymer are more uniformly distributed, and the physical characteristics of both are more likely to be expressed.

The interaction with the F polymer is likely to be enhanced by such an inorganic substance, and the dispersion stability of the present dispersion A is likely to be further improved. Further, in the molded product (for example, the polymer layer and the film described later) formed from the present dispersion liquid A, the physical characteristics based on the inorganic substance are remarkably likely to be exhibited.

Above all, in the present dispersion A, it is preferable that the inorganic substance contains silica. The content of silica in the inorganic substance is preferably 80% by mass or more, more preferably 90% by mass or more. The upper limit of the silica content is 100% by mass.

It is preferable that at least a part of the surface of the inorganic substance is surface-treated.
Examples of the surface treatment agent used for such surface treatment include polyhydric alcohols (trimethylolethane, pentaeristol, propylene glycol, etc.), saturated fatty acids (stearic acid, lauric acid, etc.), esters thereof, alkanolamines, amines (trimethylamine, etc.). Triethylamine etc.), paraffin wax, silane coupling agent, silicone, polysiloxane, aluminum, silicon, zirconium, tin, titanium, antimony and other oxides, their hydroxides, their hydrated oxides, their phosphoric acid Salt is mentioned.
Examples of the silane coupling agent include 3-aminopropyltriethoxysilane, vinyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane and 3-. Ixylpropyltriethoxysilane is preferred.

Specific examples of inorganic substances include silica ("Admafine (registered trademark)" series manufactured by Admatex Co., Ltd.) and zinc oxide surface-treated with esters such as propylene glycol dicaprate ("FINEX" manufactured by Sakai Chemical Industry Co., Ltd.). (Registered trademark) ”series, etc.), spherical fused silica (“SFP (registered trademark)” series manufactured by Denka, etc.), rutile-type titanium oxide coated with polyhydric alcohol and inorganic substances (“Typaque” manufactured by Ishihara Sangyo Co., Ltd.) (Registered trademark) "series, etc.), rutile-type titanium oxide surface-treated with alkylsilane ("JMT (registered trademark) "series manufactured by Teika Co., Ltd.), hollow silica ("E-SPECHERES "manufactured by Pacific Cement Co., Ltd." Series, "Silicas" series manufactured by Nittetsu Mining Co., Ltd., "Ecocos Fire" series manufactured by Emerson & Cumming, Hydrophobic AEROSIL series "RX200" manufactured by Aerosil Japan, etc.), Tarku ("SG" manufactured by Japan Tarku Co., Ltd.) Series, etc.), Steatite ("BST" series manufactured by Nippon Tarku, etc.), Boron Nitride ("UHP" series manufactured by Showa Denko Co., Ltd., "Denka Boron Night Ride" series manufactured by Denka Co., Ltd. (" GP", " HGP "grade"), etc.).

The shape of the inorganic particles includes granular, needle-like (fibrous), and plate-like, and specifically, spherical, scaly, layered, leaf-like, apricot kernel-like, columnar, chicken crown-like, equiaxed, and leaf-like. , Mica-like, block-like, flat plate-like, wedge-like, rosette-like, mesh-like, and prismatic. Of these, spherical and scaly are preferable, and spherical is more preferable.

The spherical inorganic particles are preferably substantially spherical. The substantially spherical shape means that the ratio of spherical particles having a ratio of the minor axis to the major axis of 0.5 or more when observed with a scanning electron microscope (SEM) is 95% or more. In the substantially spherical inorganic particles, the ratio of the minor axis to the major axis is preferably 0.6 or more, more preferably 0.8 or more. The above ratio is preferably less than 1. When such highly spherical inorganic particles are used, the inorganic substance and the F polymer are more uniformly distributed in the molded product (polymer layer or the like), and the physical properties of both are more likely to be expressed.

The aspect ratio of the scaly inorganic particles is preferably 5 or more, more preferably 10 or more. The aspect ratio is preferably 1000 or less.

As the embodiment of the particles present in the dispersion liquid A, an F polymer is used as a core, an inorganic substance is attached to the surface of the core (hereinafter, also referred to as “aspect I”), and the inorganic substance is used as a core. An embodiment in which the F polymer is attached to the surface of the core (hereinafter, also referred to as “Aspect II”) can be mentioned. Here, the "core" means a core (central part) necessary for forming the particle shape of the composite particle, and does not mean the main component in the composition of the composite particle.
The deposit (inorganic substance or F polymer) adhering to the surface of the core may be adhered only to a part of the surface of the core, or may be attached to most or the entire surface thereof. In the former case, it can be said that the deposits cling to the surface of the core like dust, in other words, a large part of the surface of the core is exposed. In the latter case, it can be said that the deposits are evenly sprinkled on the surface of the core or are in a state of covering the surface of the core, and such composite particles are formed from the core and the shell covering the core. It can be said that it has a core-shell structure.

In the present particles, the embodiment I is preferable, and the embodiment in which the F polymer and the inorganic substance are each in the form of particles is preferable. In this case, in this particle, an inorganic substance having a hardness higher than that of the F polymer and having high dispersion stability is exposed on the surface. As a result, the F polymer is less likely to be denatured, and the fluidity and handleability of the particles are likely to be improved. In addition, the dispersion stability of the particles tends to increase.

Hereinafter, the present particles of the aspect I will be described while also describing the particulate F polymer as “F particles”. The core of the F polymer may be composed of a single F particle or an aggregate of F particles. It is preferable that the D50 of the core of the F polymer is set to be larger than the D50 of the inorganic particles, and the amount of the F polymer in the particles is set to be larger than the amount of the inorganic substance in the present particles of the aspect I.

In the present particles of the aspect I, the D50 of the inorganic particles is preferably 0.001 to 0.5, more preferably 0.01 to 0.3, based on the D50 of the core of the F polymer. Specifically, it is preferable that the D50 of the core of the F polymer is more than 1 μm and the D50 of the inorganic particles is 0.1 μm or less. The amount of inorganic particles is preferably 0.1 part by mass or more, more preferably 1 part by mass or more with respect to 100 parts by mass of the F polymer. The upper limit is preferably 50 parts by mass, more preferably 25 parts by mass, and even more preferably 5 parts by mass.
In the particles of the aspect I thus obtained, the above relationship is maintained, the D50 of the core of the F polymer is larger than the D50 of the inorganic particles, and the mass of the F polymer occupying the D50 is larger than the mass of the inorganic substance. .. In this case, the surface of the core of the F polymer is coated with a larger amount of inorganic particles, and the particles have a core-shell structure. Further, in this case, the aggregation of the F particles is suppressed, and it is easy to obtain the present particles in which the inorganic particles are attached to the core composed of a single F particle.

The inorganic particles are preferably spherical, and more preferably substantially spherical particles. In such a case, the dispersibility stability of the obtained particles tends to increase. In the substantially spherical inorganic particles, the ratio of the minor axis to the major axis is preferably 0.5 or more, more preferably 0.8 or more. The above ratio is preferably less than 1. Here, the "sphere" includes not only a true sphere but also a slightly distorted sphere.
When such highly spherical inorganic particles are used, the inorganic substance and the F polymer are more uniformly distributed in the molded product (polymer layer or the like), and the physical properties of both are more likely to be expressed.
Inorganic particles may be embedded in the core of the F polymer.

In the present particles of the aspect I, the D50 of the inorganic particles is preferably in the range of 0.001 to 0.3 μm, more preferably 0.005 to 0.2 μm, still more preferably 0.01 to 0.1 μm. When D50 is in such a range, the handleability and fluidity of the particles are likely to be improved, and the dispersion stability in the dispersion liquid A is likely to be improved.
Further, the particle size distribution of the inorganic particles is preferably 3 or less, and more preferably 2.9 or less, using the value of D90 / D10 as an index. Here, "D10" is a volume-based cumulative 10% diameter of the object, which is measured in the same manner as D50 and D90. In such a case, it is easy to control the fluidity of the obtained particles.

At least a part of the surface of the inorganic particles is preferably surface-treated, and more preferably surface-treated with a silazane compound such as hexamethyldisilazane, a silane coupling agent, or the like. Examples of the silane coupling agent include the above-mentioned compounds.
As the inorganic particles, one kind may be used, or two or more kinds may be mixed and used. When two kinds of inorganic particles are mixed and used, the average particle diameters of the particles of each inorganic substance may be different from each other, and the content ratio (mass ratio) of the particles of each inorganic substance is appropriately set according to the desired function. can.

In the particles of Embodiment I, the D50 of the core of the F polymer is preferably 0.1 μm or more, more preferably more than 1 μm. The upper limit is preferably 100 μm, more preferably 50 μm, and even more preferably 10 μm.
The proportion of the F polymer in the particles of Embodiment I is preferably 50 to 99% by mass, more preferably 75 to 99% by mass. The proportion of the inorganic substance is preferably 1 to 50% by mass, more preferably 1 to 25% by mass.

The particles of Aspect I may be further surface-treated depending on the physical characteristics of the inorganic substance adhering to the surface. Specific examples of such surface treatment include a method of surface-treating the particles of Embodiment I with siloxanes such as polydimethylsiloxane or a silane coupling agent.
Such surface treatment can be carried out by mixing the dispersion liquid in which the particles are dispersed with the siloxanes or the silane coupling agent, reacting the siloxanes or the silane coupling agent, and recovering the particles. As the silane coupling agent, the above-mentioned silane coupling agent having a functional group is preferable. According to such a method, the surface physical characteristics of the particles can be further adjusted.

Hereinafter, the particles of Phase II will be described.
In the particles of Embodiment II, the F polymer may be in the form of particles or may be in the form of non-particulates. It is preferable that at least a part of the F polymer is fused to the inorganic core.
In the particles of Embodiment II, the D50 of the inorganic core is preferably 1 μm or more, more preferably more than 3 μm. The upper limit is preferably 40 μm, more preferably 30 μm.
In the present particles of Aspect II, when the F polymer is in the form of particles, the D50 of the F particles is preferably in the range of 0.1 to 10 μm, more preferably 1 to 5 μm. If it is within the range where D50 is applied, the handleability and fluidity of the particles are likely to be improved, and the dispersion stability is likely to be improved.
Further, the proportion of the inorganic substance in the particles of Embodiment II is preferably 50 to 99% by mass, more preferably 60 to 90% by mass. The proportion of the F polymer is preferably 1 to 50% by mass, more preferably 10 to 40% by mass.

The D50 of the particles is preferably 30 μm or less, more preferably 20 μm or less. The D50 of the particles is preferably 0.1 μm or more, more preferably 1 μm or more, still more preferably 3 μm or more.
The D90 of the present particles is preferably 30 μm or less, more preferably 20 μm or less.
When D50 and D90 of the present particles are within such a range, the dispersion stability of the present particles in the present dispersion liquid A and the physical properties of the molded product (polymer layer, etc.) obtained from the present dispersion liquid A are more likely to be improved. ..

The present particles are a method of colliding F particles and inorganic particles at a temperature equal to or higher than the melting temperature of the F polymer and in a suspended state (hereinafter, also referred to as “dry method A”), F particles and inorganic particles. , It is preferable to manufacture by a method of colliding in a pressed or sheared state (hereinafter, also referred to as “dry method B”).
Alternatively, it can also be produced by a method of shearing a liquid composition containing F particles and inorganic particles to coagulate the F particles (hereinafter, also referred to as “wet method”).

In the dry method A, for example, the F particles and the inorganic particles are supplied in an atmosphere of high temperature turbulence, and the F particles collide with the inorganic particles to apply stress between them to form a composite. Such a dry method A may be referred to as a hybridization treatment.
The atmosphere is formed by gas. Examples of the gas that can be used include air, oxygen gas, nitrogen gas, argon gas, or a mixed gas thereof.
The F particles and the inorganic particles may be collectively supplied under the atmosphere as a mixture premixed, or may be separately supplied under the atmosphere.

When supplying F particles and inorganic particles in a high temperature atmosphere, it is preferable that the particles do not aggregate with each other. As such a method, a method of suspending particles in a medium (gas or liquid) can be used. A mixture of gas and liquid may be used as a medium.
Further, in the dry method A, after preparing an atmosphere of high temperature turbulence, F particles and inorganic particles may be supplied into the atmosphere, and after the F particles and the inorganic particles are suspended in the medium, the medium is used. May be heated to form a high temperature turbulent atmosphere.
As a device that can be used in the former, for example, in a cylindrical container, the particles are agitated by a stirring body that rotates at a high speed such as a stirring blade, and the particles are moved between the inner wall of the container and the stirring body. A device for pinching and applying stress, for example, "Hybridation System" (registered trademark) manufactured by Nara Machinery Co., Ltd. can be mentioned.
The temperature of the atmosphere is preferably 80 ° C. or higher, and preferably 110 ° C. or higher. The temperature of the atmosphere is preferably 400 ° C. or lower, more preferably 200 ° C. or lower, and even more preferably 120 ° C. or lower.
In the case of the dry method A, the D50 of the F particles and the silica particles may collide with the particles in the above range at a temperature equal to or higher than the melting temperature of the F polymer and in a suspended state. It is preferable to collide 15 to 85 parts by mass of silica with respect to 100 parts by mass of the F polymer at a temperature equal to or higher than the melting temperature of the F polymer and in a suspended state.
When the inorganic particles contain a large amount of aggregates in which the primary particles are aggregated, the aggregates may be crushed prior to being supplied in a high temperature atmosphere. Examples of the method for crushing the agglomerate include a method using a jet mill, a pin mill, and a hammer mill.

In the dry method B, for example, F particles and inorganic particles are pressed against the inner peripheral surface (receiving surface) of a cylindrical rotating body rotating around the central axis by centrifugal force, and are arranged at a short distance from the inner peripheral surface. In cooperation with the inner piece, the particles are compounded by applying a pressing force or a shearing force. Such a dry method B may be called a mechanofusion treatment.
The atmosphere inside the cylindrical rotating body can be an inert gas atmosphere or a reducing gas atmosphere. The temperature of the atmosphere is preferably not less than the melting temperature of the F polymer, more preferably 100 ° C. or less.
The separation distance between the inner peripheral surface of the tubular rotating body and the inner piece is appropriately set according to the average particle diameter of the F particles and the inorganic particles. This separation distance is usually preferably 1 to 10 mm.
The rotation speed of the cylindrical rotating body is preferably 500 to 10000 rpm. In this case, it is easy to increase the production efficiency of the particles.
When the inorganic particles contain a large amount of aggregates in which the primary particles are aggregated, the aggregates are disassembled in the same manner as described in the above-mentioned dry method A prior to supplying the particles into the cylindrical rotating body. You may crush it.

In the dry method B, the rotating shaft is arranged in the horizontal direction, and a rotary tank having an elliptical (odd) cross section and a crushing and mixing chamber is rotatably inserted into the crushing and mixing chamber of the rotary tank to rotate the rotating shaft. It is also performed by using a crushing / mixing device (for example, "Nobilta" (registered trademark) manufactured by Hosokawa Micron), which is arranged concentrically with the rotation axis of the rotary tank and has a crushing / mixing blade having an elliptical (odd) cross section. be able to.
In such a crushing / mixing device, F particles and inorganic particles are pressed between the short-diameter portion of the crushing / mixing chamber and the long-diameter portion of the crushing / mixing blade, and pressing pressure or shearing force is applied to the particles to form a composite. Further, in the crushing / mixing device, the rotation direction of the rotary tank and the rotation direction of the crushing / mixing blade are preferably opposite to each other, and the rotation speed of the rotary tank is preferably set to be slower than the rotation speed of the crushing / mixing blade.
According to such a pulverizing and mixing apparatus, the pulverizing and mixing chamber and the pulverizing and mixing blade have irregular cross sections, and a momentary pressing force or shearing force is applied to F particles and inorganic particles that flow by falling due to their own weight in the pulverizing and mixing chamber. Can be given repeatedly. Therefore, the particles can be pulverized and mixed in a short time while reducing the adverse effect of heat on the particles, so that the particles having the desired characteristics can be easily obtained.

In the wet method, a liquid composition containing F particles and inorganic particles is, for example, stirred and sheared to destabilize the particles, causing coagulation and complexing the F particles and the inorganic particles to obtain the present particles. The method. When the inorganic particles are silica, colloidal silica can be preferably used.

In the wet method, the total content of the F particles and the inorganic particles in the liquid composition is preferably 30% by mass or more, more preferably 40 to 80% by mass, based on the total mass of the liquid composition.
Further, the mass ratio of the F particles to the inorganic particles in the liquid composition is preferably 0.001 to 2.0, with the mass of the F particles being 1, and more specifically, the mass of the inorganic particles. In the case of obtaining the present particles of the aspect I, it is preferable that the liquid composition contains 20 to 50% by mass of F particles and 0.1 to 40% by mass of inorganic particles.

The liquid composition can be prepared by mixing F particles, inorganic particles, and a dispersion medium. As a mixing method, F particles and inorganic particles are collectively added to the dispersion medium and mixed; a method in which F particles and inorganic particles are sequentially added to the dispersion medium and mixed; F particles and inorganic particles are mixed in advance. A method of mixing particles and mixing the obtained mixture and a dispersion medium; a method of premixing F particles and a dispersion medium, a method of premixing inorganic particles and a dispersion medium, and further mixing the obtained two kinds of mixtures; etc. Can be mentioned.
Specifically, after the silica particles are dispersed in a dispersion medium, this is added to a dispersion liquid containing F particles and mixed. Such a method is advantageous for mixing silica particles and F particles.
If the mixture containing the F particles and the silica particles is destabilized and the solidification is caused, the F particles and the silica particles are composited.
As the dispersion medium, a compound of the same type as the liquid dispersion medium described later can be preferably used.

The liquid composition containing F particles may be stirred during the addition of the inorganic particles or after the addition is completed. Examples of the device used for stirring include a stirring device provided with blades such as propeller blades, turbine blades, paddle blades, and shell-shaped blades as stirring blades. The stirring speed at this time may be such that the inorganic particles can be efficiently dispersed in the liquid composition containing the F particles, and it is not necessary to apply a high shearing force to the F particles.

For stirring the liquid composition, for example, stirring by the above-mentioned stirring device, Henschel mixer, pressurized kneader, Banbury mixer or planetary mixer; ball mill, attritor, basket mill, sand mill, sand grinder, dyno mill (glass beads or Mixing with a disperser using a medium such as a crushing medium such as zirconium oxide beads), dispermat, SC mill, spike mill or agitator mill; high pressure homogenizer such as microfluidizer, nanomizer, ultimateizer, ultrasonic wave. Mixing using a media-free disperser such as a homogenizer, a resolver, a dispenser, a high-speed impeller disperser, and a rotation / revolution agitator is included.
The shearing process is preferably under high shear conditions. "High shear" means, in the case of agitation, agitation at a rate greater than at least 300 rpm.
The shearing treatment may be started during the addition of the inorganic particles to the liquid composition containing the F powder, or may be performed after the addition is completed.

As a means for isolating the particles by removing the dispersion medium after the shearing treatment, heating, depressurization or filtration may be mentioned, and these may be used in combination as appropriate.
Specific examples of the means for isolating the particles include (1) distilling off the dispersion medium under atmospheric pressure or reduced pressure to concentrate, filtering and drying as necessary; (2) controlling the temperature of the liquid composition. While agglomerating the particles, or after coagulation / crystallization by adding an electrolyte, a coagulant, a coagulation aid, etc., the particles are separated and dried by filtration or the like; (3) The dispersion medium can volatilize the liquid composition. It is sprayed into a dry gas having a temperature at a suitable temperature, dried, and recovered; (4) the liquid composition is centrifuged and then dried.
Here, examples of the drying means include vacuum drying, high frequency drying, and hot air drying.
In each of the above means (1) to (4), if necessary, the liquid composition may be diluted with a dispersion medium to adjust the total content of the F polymer and the inorganic substance in the liquid composition in advance.

In the production of the particles by the dry method A, the dry method B, and the wet method described above, the F particles are mixed with the inorganic particles prior to the mixing with the inorganic particles from the viewpoint of further enhancing the adhesion (adhesiveness) with the inorganic particles. , Or it is preferable to perform surface treatment at the same time as mixing. Examples of the surface treatment include plasma treatment, corona discharge treatment, corona discharge treatment, etching treatment, electron beam irradiation treatment, ultraviolet irradiation treatment, and ozone exposure treatment, and plasma treatment, particularly low temperature plasma treatment, is preferable.
Further, according to the dry method A and the dry method B, when the F particles and the inorganic particles collide with each other, heat is easily transferred uniformly to these particles, and the densification and spheroidization of the particles are likely to proceed. In this case, the sphericity of the particles is preferably 0.5 or more, preferably 0.93 to 0.99.

In the production of the present particles, the D50 of the F particles is preferably 20 μm or less, more preferably 10 μm or less. The D50 of the F particles is preferably 0.01 μm or more, more preferably 0.1 μm or more. The D90 of the F particles is preferably 10 μm or less. In D50 and D90 in this range, the fluidity and dispersibility of the F particles are good, and it is easy to control the size of the particles present in the dispersion medium so as to be difficult to settle by the wet method.
The bulk density of the F particles ^{is preferably 0.15 g / m 2} or more, more preferably 0.20 g / m ² or more. The bulk density of F particles is preferably from 0.50 g / ^{m 2} or less, 0.35 g / ^{m 2} or less is more preferable.

The particles can be stably dispersed even if a large amount is added to the liquid dispersion medium, and in the molded product (polymer layer, film, etc.) formed from the dispersion liquid A, the F polymer and the inorganic substance are more uniformly distributed. Therefore, the physical properties of the F polymer (electrical properties, adhesiveness, etc.) and the physical properties of the inorganic substances (low linear expansion, etc.) are highly likely to be expressed. In addition, the physical characteristics (UV absorption, etc.) of the aromatic polymer are highly likely to be expressed.

In the present dispersion A, the liquid dispersion medium is preferably a compound that is liquid at 25 ° C. under atmospheric pressure. The liquid dispersion medium may be polar or non-polar, and is preferably polar. The liquid dispersion medium is more preferably at least one selected from water, amides, ketones and esters. The boiling point of the liquid dispersion medium is preferably in the range of 50 to 240 ° C. As the liquid dispersion medium, one type may be used alone, or two or more types may be used in combination. It is considered that when such a liquid dispersion medium is used, the dispersed state of the particles in the dispersion A can be kept more constant.
As the liquid dispersion medium, water, N, N-dimethylformamide, N, N-dimethylacetamide, 3-methoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropanamide, N-methyl- Examples include 2-pyrrolidone, γ-butyrolactone, cyclohexanone, cyclopentanone, butyl acetate, methylisopropylketone, methylethylketone and toluene, as well as water, N-methyl-2-pyrrolidone, γ-butyrolactone, methylethylketone, cyclohexanone and cyclopentanone. Preferably, N-methyl-2-pyrrolidone and methylethylketone are more preferable.
The content of the liquid dispersion medium in the dispersion liquid A is preferably 30 to 90% by mass, more preferably 50 to 80% by mass.

The dispersion A further contains an aromatic polymer. The content of the aromatic polymer in the dispersion liquid A is preferably 0.1% by mass or more, more preferably 1% by mass or more. The content of the aromatic polymer is preferably 40% by mass or less, more preferably 20% by mass or less.
Further, the content of the aromatic polymer in the dispersion liquid A is preferably smaller than the content of the particles. Specifically, the ratio (mass ratio) of the content of the aromatic polymer to the content of the particles in the dispersion A by mass is preferably 0.01 or more, more preferably 0.1 or more. On the other hand, the above ratio is preferably 0.5 or less, more preferably 0.3 or less. Even when the aromatic polymer is contained in such a ratio, the present dispersion A is excellent in state stability due to the above-mentioned mechanism of action.

The aromatic polymer may be thermosetting, may be thermoplastic, and is preferably thermoplastic. In such a case, the present dispersion A tends to have excellent dispersion stability.
Examples of the aromatic polymer include a unit containing an imide bond, a unit containing an amide bond, or an aromatic polymer having an N-substituted maleimide structure, a succinateimide structure or a phthalimide structure (specifically, aromatic polyimide or aromatic). Examples thereof include polyamideimide, a precursor of aromatic polyamideimide, aromatic maleimide, aromatic polyamic acid which is an aromatic polyimide precursor, aromatic polyamide), polyphenylene ether, liquid crystal polyester, or aromatic elastomer (styrene elastomer and the like). ..

As the aromatic polyimide, a semi-aromatic polyimide in which one of the tetracarboxylic acid dianhydride and the diamine has an aromatic ring, or a total aromatic polyimide in which both have an aromatic ring is more preferable. Specific examples of aromatic polyimides include "Yupia (registered trademark) -AT" series (manufactured by Ube Industries), "Neoprim" series (manufactured by Mitsubishi Gas Chemical Company), "Spixeria" series (manufactured by Somar), and "Q". -PILON "series (manufactured by PI Technology Research Institute)," WINGO "series (manufactured by Wingo Technology Co., Ltd.)," Tomid "series (manufactured by T & K TOKA)," KPI-MX "series (manufactured by Kawamura Sangyo Co., Ltd.) ..
Specific examples of the aromatic polyamide-imide or its precursor include "HPC-1000" and "HPC-2100D" (both manufactured by Showa Denko Materials Co., Ltd.).

As the aromatic maleimide, a maleimide resin having an N-substituted maleimide structure is preferable, and it is a reaction product of a diamine such as dimerdiamine and a diamine having an alicyclic structure with a tetracarboxylic acid dianhydride having an aromatic ring, and is a terminal. Examples thereof include a bismaleimide resin obtained by reacting polyimide having an amino group with maleic anhydride. The bismaleimide resin may have an N-substituted maleimide structure only in the terminal group, or may have an N-substituted maleimide structure in both the terminal group and the side chain.
These maleimide compounds are commercially available as BMI series manufactured by DESIGNER MOLECULES Inc.

Examples of the liquid crystal polyester include aromatic polyesters and aromatic polyester amides having an amide bond introduced therein. In the aromatic polyester or aromatic polyester amide, an isocyanate-derived bond such as an imide bond, a carbonate bond, a carbodiimide bond or an isocyanurate bond may be further introduced.
The liquid crystal polyester is preferably thermoplastic, more preferably a liquid crystal polyester having a melting temperature in the range of 260 to 360 ° C, and even more preferably in the range of 270 to 350 ° C.
Among the liquid crystal polyesters, polyesters containing at least a unit based on p-hydroxybenzoic acid (HBA) or a unit based on 6-hydroxy-2-naphthoic acid (HNA) are preferable, and polyesters containing HBA units and HNA units, HBA or At least one aromatic hydroxycarboxylic acid unit of HNA, at least one aromatic diol unit of 4,4'-dihydroxybiphenyl or hydroquinone, and at least a terephthalic acid, isophthalic acid or 2,6-naphthalenedicarboxylic acid. Polyester containing one aromatic dicarboxylic acid unit, HBA unit and polyester containing 2,6-dihydroxynaphthoic acid unit; polyester containing 2,6-dihydroxynaphthoic acid unit, terephthalic acid unit and acetaminophen unit; HBA unit, Polyesters containing terephthalic acid units and 4,4'-biphenol units are preferred. These liquid crystal polyesters are industrially manufactured and available, including Celanese Japan's "Vector" series, JX Energy's "XYDAR" series, and Polyplastics'"Laperos" series. , Ueno Pharmaceutical Co., Ltd.'s "UENO LCP" series and the like.

The styrene elastomer is preferably a styrene elastomer that has both rubber and plastic properties and is plasticized by heating to exhibit flexibility, and is a copolymer of styrene and conjugated diene or (meth) acrylic acid ester (styrene-butadiene rubber; styrene). Styrene-based core-shell copolymer; styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, and styrene-isoprene-styrene block copolymer Styrene-based block copolymers such as coalesced hydrogenated substances) are mentioned, and styrene elastomers having both rubber and plastic properties and exhibiting flexibility by being plasticized by heating are preferable.

In the present invention, it is preferable that the aromatic polymer is at least one selected from the group consisting of aromatic polyimide, aromatic polyamide, aromatic polyamideimide, polyphenylene ether, liquid crystal polyester, and aromatic maleimide.
Further, from the viewpoint of high dispersion stabilizing effect of the present dispersion liquid A, the aromatic polymer is preferably thermoplastic, and among them, thermoplastic aromatic polyimide or aromatic polyamideimide is more preferable and thermoplastic. Aromatic polyimide is more preferred. In this case, it is considered that the thermoplastic aromatic polyimide or aromatic polyamide-imide acts as a surfactant, a viscosity modifier, or both in the dispersion A. Therefore, the physical characteristics (viscosity, thixotropic ratio, etc.) of the dispersion liquid A are balanced, and the handleability thereof is likely to be improved. Then, the adhesiveness and low line expandability of the molded product formed from the present dispersion A are further improved.

Further, at least a part of the aromatic polymer may be dispersed in particles in the present dispersion A. In such a case, particulate liquid crystal polyester can be preferably used.
When a particulate liquid crystal polyester is used, the average particle size (D50) is preferably in the range of 1 to 40 μm, more preferably 5 to 20 μm. If the average particle size (D50) is within such a range, the dispersion stability in the present dispersion A is likely to be further enhanced.

The present dispersion A may or may not further contain a surfactant. When the present dispersion A contains a surfactant, the content thereof is preferably 1 to 15% by mass, and the surfactant is preferably nonionic.
As the surfactant, a glycol-based surfactant, an acetylene-based surfactant, a silicone-based surfactant and a fluorine-based surfactant are preferable. The fluorine-based surfactant is a compound having a hydrophilic moiety and a hydrophobic moiety containing a fluorine-containing organic group. One type of surfactant may be used, or two types may be used. When two kinds of surfactants are used, the surfactants are preferably a silicone-based surfactant and a glycol-based surfactant.
Specific examples of surfactants include "Futergent" series (manufactured by Neos), "Surflon" series (manufactured by AGC Seimi Chemical), "Megafuck" series (manufactured by DIC), and "Unidyne" series (manufactured by Daikin Industries). (Made by), "BYK-347", "BYK-349", "BYK-378", "BYK-3450", "BYK-3451", "BYK-3455", "BYK-3456" (Big Chemie Japan) , "KF-6011", "KF-6043" (manufactured by Shin-Etsu Chemical Co., Ltd.), "Tergitol" series (manufactured by Dow Chemical Corporation, "Tergitol TMN-100X", etc.).

The dispersion liquid A is excellent in dispersion stability and handleability even if it does not necessarily contain a surfactant, particularly a fluorine-based surfactant, due to the above-mentioned mechanism of action. The dispersion liquid A preferably does not contain a fluorine-based surfactant. The molded product formed from the present dispersion A, which does not contain a fluorine-based surfactant, tends to further improve low dielectric loss tangent properties and the like.

The present dispersion A may further contain a resin material other than the F polymer and the above-mentioned aromatic polymer from the viewpoint of improving the adhesiveness and low linear expansion property of the molded product formed from the present dispersion A. .. Such a resin material may be thermosetting or thermoplastic, may be modified, may be dissolved in the present dispersion A, or may be dispersed without being dissolved.
Examples of such resin materials include tetrafluoroethylene polymers other than F polymers, acrylic resins, phenol resins, polyolefin resins, modified polyphenylene ethers, vinyl ester resins, urea resins, diallyl phthalate resins, melamine resins, guanamine resins, and melamine-urea. Examples thereof include condensed resin, polycarbonate, epoxy resin and the like.
From the viewpoint of improving the electrical properties of the molded product formed from the dispersion liquid A, it is preferable that the resin material is a tetrafluoroethylene-based polymer other than the F polymer. Examples of the tetrafluoroethylene-based polymer other than the F polymer include polytetrafluoroethylene (PTFE), and examples thereof include high-molecular-weight PTFE, low-molecular-weight PTFE, and modified PTFE having fibril properties. The low molecular weight PTFE or modified PTFE also includes a copolymer of TFE and a trace amount of comonomer (HFP, PAVE, FAE, etc.).
When the dispersion liquid A contains a resin material, the content thereof is preferably 40% by mass or less with respect to the entire dispersion liquid A.

The dispersion liquid A may further contain a tetrafluoroethylene-based polymer in addition to the F polymer contained in the particles. Even in such a case, the present dispersion A tends to be excellent in dispersion stability.
The tetrafluoroethylene-based polymer may be the same type of polymer as the F polymer constituting the present particles or a different kind of polymer as described above. Among them, PTFE or F polymer is preferable, PFA or FEP is more preferable, and the above-mentioned polymer (1) or polymer (2) is further preferable.
The tetrafluoroethylene polymer is preferably in the form of particles, and is preferably dispersed in the present dispersion A. Further, the particles of the tetrafluoroethylene-based polymer may be composed of only the tetrafluoroethylene-based polymer, or may contain the tetrafluoroethylene-based polymer and other components (such as the resin material described above).

The dispersion liquid A may further contain inorganic particles in addition to the inorganic particles contained in the particles. Examples of the inorganic particles include the above-mentioned particles of the inorganic substances that may constitute the present particles. As the inorganic particles, one kind may be used, or two or more kinds may be mixed and used. When the present dispersion A further contains inorganic particles, the content thereof is preferably in the range of 1 to 50% by mass and more preferably 5 to 30% by mass with respect to the entire dispersion A. The ratio (mass ratio) of the content of the inorganic particles to the content of the particles in the dispersion A is preferably 0.01 to 2, more preferably 0.1 to 1.

In addition to the above components, the present dispersion A contains a thixotropic agent, a viscosity modifier, a defoaming agent, a silane coupling agent, a dehydrating agent, a plasticizer, a weather resistant agent, and an oxidation, as long as the effects of the present invention are not impaired. It may further contain other components such as an inhibitor, a heat stabilizer, a lubricant, an antistatic agent, a whitening agent, a colorant, a conductive agent, a mold release agent, a surface treatment agent, a flame retardant, and various fillers.

The dispersion liquid A can be prepared by mixing the particles, an aromatic polymer, a liquid dispersion medium, and if necessary, other components such as the above-mentioned surfactant, and stirring the mixture. For stirring, the same means as the stirring device mentioned in the above-mentioned wet method and the means used for the shearing treatment can be applied.
The content of the particles in the dispersion liquid A is preferably 20% by mass or more, more preferably 40 to 80% by mass, based on the total mass of the dispersion liquid A. At the same time, it is preferable that the content of the F polymer is 10% by mass or more with respect to the total mass of the present dispersion A.
Further, it is preferable that the mass ratio of the F particles to the inorganic substance in the present particles is 0.01 to 2.0, where the mass of the F particles is 1. From the viewpoint that a molded product such as a layer can be suitably formed from the dispersion liquid A, the dispersion liquid A contains 20 to 40% by mass of F particles, 5 to 40% by mass of an inorganic substance, and 0.1 by mass of an aromatic polymer. It is preferably contained in an amount of about 30% by mass.

The viscosity of this dispersion A at 25 ° C. is 1000 to 100,000 mPa · s. The viscosity of the dispersion A at 25 ° C. is preferably 5000 mPa · s or more, and more preferably 10,000 mPa · s or more. The viscosity of the dispersion A at 25 ° C. is preferably 100,000 mPa · s or less, more preferably 50,000 mPa · s or less, and even more preferably 20,000 mPa · s or less. In this case, the dispersion liquid A has excellent coatability and easily forms a molded product (polymer layer or the like) having an arbitrary thickness.
Further, in the present dispersion A having a viscosity in such a range, particularly a high viscosity range, the inorganic substances are less likely to aggregate and are easily uniformly distributed in the molded product formed from the dispersion liquid A, so that the physical properties of the F polymer and the inorganic substances are further improved. Highly easy to express.

The thixotropic ratio of the dispersion liquid A is preferably 1.0 or more. The thixotropy of the dispersion A is preferably 3.0 or less, more preferably 2.0 or less. In this case, the dispersion liquid A is excellent in coatability and homogeneity, and it is easy to form a more dense molded product (polymer layer or the like).
The dispersion liquid A is easy to adjust to the viscosity or thixotropic property in such a range, and is excellent in handleability.

In the present dispersion A, the component sedimentation rate is preferably 60% or more, preferably 70% or more, and more preferably 80% or more. Here, the component sedimentation rate is the dispersion liquid in the screw pipe after the main dispersion liquid A (18 mL) is placed in a screw tube (internal volume: 30 mL) and allowed to stand at 25 ° C. for 14 days. It is a value calculated by the following formula from the total height and the height of the sedimentation layer (dispersion layer). If the sedimentation layer is not confirmed after standing and there is no change in the state, it is assumed that the height of the entire dispersion liquid does not change, and the component sedimentation rate is 100%.
Erythrocyte sedimentation rate (%) = (height of sedimentation layer) / (height of the entire dispersion) x 100

The present dispersion A is brought into contact with the surface of the base material layer and heated to form a polymer layer, and a laminate having the base material layer and the polymer layer is obtained. More specifically, the present dispersion A is brought into contact with the surface of the base material layer to form a liquid film, the liquid film is heated to remove the dispersion medium to form a dry film, and the dry film is further heated. Then, when the F polymer is fired, a laminate having a polymer layer containing the F polymer and an inorganic substance (hereinafter, also referred to as “F layer”), preferably a polymer layer containing the F polymer and silica on the surface of the base material layer. The body is obtained.
The temperature for heating the liquid coating is preferably 120 ° C to 200 ° C. On the other hand, the temperature for heating the dry film is preferably 250 ° C to 400 ° C, more preferably 300 to 380 ° C.
Examples of each heating method include a method using an oven, a method using a ventilation drying furnace, and a method of irradiating heat rays such as infrared rays.

The base material layer is a metal substrate such as a metal foil such as copper, nickel, aluminum, titanium, or an alloy thereof; polyimide, polyarylate, polysulfone, polyallylsulfone, polyamide, polyetheramide, polyphenylene sulfide, polyallyl ether ketone. , Polyamideimide, liquid crystal polyester, heat resistant resin film such as liquid crystal polyester amide; prepreg (precursor of fiber reinforced resin substrate), ceramics substrate such as silicon carbide, aluminum nitride, silicon nitride, glass substrate and the like.
The ten-point average roughness of the surface of the base material layer is preferably 0.01 to 0.05 μm.
The contact of the dispersion liquid A is preferably performed by coating, liquid discharge, or immersion, and preferably by coating.
The coating methods include spray method, roll coat method, spin coat method, gravure coat method, micro gravure coat method, gravure offset method, knife coat method, kiss coat method, bar coat method, die coat method, fountain Mayer bar method, and slot die coat. The law is mentioned.

When the liquid film is dried, the liquid film is heated at a temperature at which the dispersion medium volatilizes to form a dry film on the surface of the sheet substrate. The temperature of such heating is preferably the boiling point of the dispersion medium + 50 ° C. or lower, more preferably the boiling point of the dispersion medium or lower, and further preferably the boiling point of the dispersion medium of −50 ° C. or lower. The drying temperature is preferably 120 ° C to 200 ° C. Air may be blown in the step of removing the dispersion medium.
At the time of drying, the dispersion medium does not necessarily have to be completely volatilized, and may be volatilized to the extent that the layer shape after holding is stable and the self-supporting film can be maintained.
When firing the F polymer, it is preferable to heat the dry film at a temperature equal to or higher than the melting temperature of the F polymer. The heating temperature is preferably 380 ° C. or lower, more preferably 350 ° C. or lower.
Examples of each heating method include a method using an oven, a method using a ventilation drying furnace, and a method of irradiating heat rays such as infrared rays. The heating may be performed under normal pressure or reduced pressure. The heating atmosphere may be any of an oxidizing gas atmosphere (oxygen gas, etc.), a reducing gas atmosphere (hydrogen gas, etc.), and an inert gas atmosphere (helium gas, neon gas, argon gas, nitrogen gas, etc.). ..
The heating time is preferably 0.1 to 30 minutes, more preferably 0.5 to 20 minutes.
By heating under the above conditions, the F layer can be suitably formed while maintaining high productivity.

The thickness of the F layer is preferably 0.1 to 150 μm. Specifically, when the base material layer is a metal foil, the thickness of the F layer is preferably 1 to 30 μm. When the base material layer is a heat-resistant resin film, the thickness of the F layer is preferably 1 to 150 μm, more preferably 10 to 50 μm.
The peel strength between the F layer and the base material layer is preferably 10 N / cm or more, more preferably 15 N / cm or more. The peel strength is preferably 100 N / cm or less. By using the present dispersion liquid A, the present laminated body can be easily formed without impairing the physical properties of the F polymer in the F layer.

The dispersion liquid A may be brought into contact with only one surface of the base material layer, or may be brought into contact with both sides of the base material layer. In the former, a base material layer and a laminate having an F layer on one surface of the base material layer are obtained, and in the latter, a laminate having an F layer on both the surfaces of the base material layer and the base material layer is obtained. Is obtained. Since the latter laminated body is less likely to warp, it is excellent in handleability during its processing.
Specific examples of such a laminate include a metal foil, a metal-clad laminate having an F layer on at least one surface of the metal foil, a polyimide film, and a multilayer film having an F layer on both surfaces of the polyimide film. Can be mentioned.

As the metal foil, a metal foil with a carrier containing two or more layers of metal foil may be used. Examples of the metal foil with a carrier include a copper foil with a carrier having a thickness of 10 to 35 μm and an ultrathin copper foil having a thickness of 2 to 5 μm laminated on the carrier copper foil via a release layer. Be done. By using such a copper foil with a carrier, it is possible to form a fine pattern by an MSAP (modified semi-additive) process. As the release layer, a metal layer containing nickel or chromium or a multilayer metal layer in which the metal layers are laminated is preferable.
Specific examples of the metal foil with a carrier include the trade name "FUTF-5DAF-2" manufactured by Fukuda Metal Leaf Powder Industry Co., Ltd.

The outermost surface of such a laminate may be further surface-treated in order to further improve its low line expandability and adhesiveness. However, the outermost surface of the laminate is the surface of the F layer on the opposite side to the base material.
Examples of the surface treatment method include corona treatment, plasma treatment, ozone treatment, excimer treatment, and silane coupling treatment.
Examples of the gas used for the plasma treatment include oxygen gas, nitrogen gas, rare gas such as argon, hydrogen gas, ammonia gas, and vinyl acetate. One type of these gases may be used, or two or more types may be used in combination.
Such a laminate may be further annealed in order to further improve its low line expansion engagement. The conditions for the annealing treatment are preferably 120 to 180 ° C., a pressure of 0.005 to 0.015 MPa, and a time of 30 to 120 minutes.

Another substrate may be further laminated on the outermost surface of the laminated body.
Examples of other substrates include a heat-resistant resin film, a prepreg which is a precursor of a fiber-reinforced resin plate, a laminate having a heat-resistant resin film layer, and a laminate having a prepreg layer.
The prepreg is a sheet-like substrate made of reinforcing fibers such as glass fiber or carbon fiber, in which a base material such as tow or woven fabric is impregnated with a thermosetting resin or a thermoplastic resin.
The heat-resistant resin film is a film containing one or more heat-resistant resins, and examples of the heat-resistant resin include the above-mentioned resins, and aromatic polyimide is particularly preferable.

Examples of the laminating method include a method of heat-pressing the laminated body and another substrate.
When the other substrate is a prepreg, the hot press conditions are preferably such that the temperature is 120 to 400 ° C., the atmospheric pressure is a vacuum of 20 kPa or less, and the press pressure is 0.2 to 10 MPa. Since such a laminate has an F layer having excellent electrical characteristics, it is suitable as a printed circuit board material. Specifically, such a laminate can be used for manufacturing a printed circuit board as a flexible metal-clad laminate or a rigid metal-clad laminate, and can be particularly preferably used for manufacturing a flexible printed circuit board as a flexible metal-clad laminate.

A printed circuit board is obtained by etching a laminated metal foil such as a metal foil with an F layer whose base material layer is a metal foil to form a transmission circuit. Specifically, by a method of etching a metal foil and processing it into a predetermined transmission circuit, or a method of processing the metal foil into a predetermined transmission circuit by an electrolytic plating method such as a semi-additive method (SAP method) or an MSAP method. , Can manufacture printed circuit boards.
A printed circuit board manufactured from a metal foil with an F layer has a transmission circuit formed from the metal foil and an F layer in this order. Specific examples of the configuration of the printed circuit board include a transmission circuit / F layer / prepreg layer and a transmission circuit / F layer / prepreg layer / F layer / transmission circuit.
In the manufacture of such a printed circuit board, an interlayer insulating film may be formed on the transmission circuit, a solder resist may be laminated on the transmission circuit, or a coverlay film may be laminated on the transmission circuit. These interlayer insulating films, solder resists and coverlay films may be formed with the present dispersion liquid A.

The laminate of the F layer and other base materials is useful as antenna parts, printed substrates, aircraft parts, automobile parts, sports equipment, food industry supplies, paints, cosmetics, etc., and specifically, wire coating. Materials (aircraft wires, etc.), electrical insulating tapes, insulating tapes for oil drilling, materials for printed substrates, separation membranes (precision filtration membranes, ultrafiltration membranes, reverse osmosis membranes, ion exchange membranes, dialysis membranes, gas separation membranes) Etc.), electrode binders (for lithium secondary batteries, fuel cells, etc.), copy rolls, furniture, automobile dashboards, covers for home appliances, sliding members (load bearings, sliding shafts, valves, bearings, gears, cams, etc.) , Belt conveyor, food transport belt, etc.), tools (shovel, razor, cut, saw, etc.), boiler, hopper, pipe, oven, baking mold, chute, die, toilet bowl, container covering material.

The second dispersion of the present invention is a dispersion containing the particles and a liquid dispersion medium in which the particles are dispersed in the liquid dispersion medium, and the liquid dispersion medium has two types having different boiling points. The two types of liquid dispersion media, which contain a liquid dispersion medium, are dispersion liquids (hereinafter, also referred to as “main dispersion liquid B”) which are related to form a eutectic mixture.

The present dispersion B is excellent in dispersion stability. Further, the molded product obtained from the present dispersion B is dense and has excellent surface characteristics such as appearance (flatness and texture of the surface). The correlation between the dispersion stability of the present dispersion B and the reason for improving the appearance of the obtained molded product and the composition of the present dispersion B and the mechanism of action are not necessarily clear, but are considered as follows.
Composite particles containing a tetrafluoroethylene polymer and an inorganic substance generally tend to adsorb or support a dispersion medium. Therefore, it takes time to volatilize or evaporate when the dispersion medium containing the composite particles is applied to the surface of the base material to form a liquid film and then the dispersion medium is removed by means such as heating, and the production efficiency of the molded product is high. It tends to lead to a decrease in accuracy. On the other hand, when a molded product is produced from the dispersion liquid, even if the dispersion medium constituting the dispersion liquid has a property of being too volatile or easily evaporating, the composite particles are not sufficiently packed and the surface of the obtained molded product is smooth. It tends to lead to deterioration of sex.
Since the dispersion B contains two types of liquid dispersion media having different boiling points and forming an azeotropic mixture, it is considered that the dispersion medium can be volatilized at an appropriate evaporation rate. In addition, since the liquid dispersion medium having a high boiling point gradually volatilizes or evaporates, the particles are tightly packed, surface roughness due to sudden bubble generation, etc. can be suppressed, and the appearance of the obtained molded product can be improved. Conceivable.

Further, the present particles include F polymer and inorganic particles. The F polymer has low surface energy and low dispersion stability, but the particles in which the F polymer and the inorganic substance are fused are more likely to interact with other particles and the liquid dispersion medium than the F polymer, resulting in dispersion stability. It is considered to be excellent.
As a result, it is considered that the dispersion liquid B was able to form a dense molded product having high physical properties of the F polymer and the physical properties of the inorganic substance and having high component uniformity and excellent electrical characteristics and appearance.

The details of the F polymer and the particles in the dispersion B are the same as those described above in the description of the dispersion A.

Further, in the dispersion liquid B, the F particles constituting the particles may contain a resin other than the F polymer such as aromatic polyester, polyamide-imide, thermoplastic polyimide, polyphenylene ether, and polyphenylene oxide, but F. It is preferable to use a polymer as a main component. The content of the F polymer in the F particles is preferably 80% by mass or more, more preferably 100% by mass.

The particles can be stably dispersed even if a large amount is added to the liquid dispersion medium, and in the molded product (polymer layer, film, etc.) formed from the dispersion liquid B, the F polymer and the inorganic substance are more uniformly distributed. Therefore, the physical properties of the F polymer (electrical properties, adhesiveness, etc.) and the physical properties of the inorganic substances (low linear expansion, etc.) are highly likely to be expressed.

The present dispersion B contains two types of liquid dispersion media having different boiling points. The two types of liquid dispersion media are in a relationship of forming an azeotropic mixture. Here, the "azeotropic mixture" is a mixture having the same composition of the gas phase and the liquid phase.
The azeotropic mixture can take either uniform or non-uniform mode by selecting two liquid dispersion media. From the viewpoint of improving productivity and process passability in the process of obtaining a molded product from the present dispersion B, a uniform azeotropic mixture is preferable.

In the present dispersion B, the mixing amount ratio of the dispersion medium having a high boiling point in the two types of liquid dispersion media having different boiling points is that of the dispersion medium having a high boiling point in the azeotropic mixture of the two types of liquid dispersion media. It is preferably more than the composition ratio (mass ratio).
The composition ratio of the azeotropic mixture can vary widely depending on the choice of the two liquid dispersion media. Specifically, when the liquid dispersion medium having a low boiling point is the dispersion medium S1 and the liquid dispersion medium having a high boiling point is the dispersion medium S2, the composition ratio (mass ratio) of S1 to S2 in the present dispersion liquid B is. It is preferably higher than the composition ratio (mass ratio) of S1 to S2 in the azeotropic mixture of S1 and S2.
Further, the co-boiling point of the azeotropic mixture is preferably lower than the boiling point of the dispersion medium having a high boiling point among the two types of liquid dispersion media, and the co-boiling point is the boiling point of either of the two types of liquid dispersion media. It is more preferable that it is lower than.
With such a mixing amount ratio and azeotropic point, even a dispersion medium having a high boiling point can be easily removed as an azeotropic mixture at a lower temperature in the drying process when producing a molded product from the present dispersion B. Therefore, it is easy to improve the productivity and the appearance of the molded product at the same time. In addition, the remaining high boiling point liquid dispersion medium acts like a lubricant in the process of removing the liquid dispersion medium, promoting the packing of the particles and forming a uniform molded product with less surface roughness. It is thought to assist.

Both of the above two types of liquid dispersion media are preferably compounds that are liquid at 25 ° C. under atmospheric pressure, and may be polar or non-polar.
The boiling points of the two types of liquid dispersion media are preferably in the range of 50 to 240 ° C. Further, at least one of the two liquid dispersion media is more preferably water, alcohol or amide.
It is considered that when such a liquid dispersion medium is used, the dispersed state of the particles in the dispersion B can be kept more constant.

The liquid dispersion medium includes water [boiling point: 100 ° C. (boiling point under atmospheric pressure; the same applies hereinafter unless otherwise specified)], ethylene glycol (boiling point: 197 ° C.), N, N-dimethylformamide (boiling point: 153). ° C.), N, N-dimethylacetamide (boiling point: 165 ° C.), 3-methoxy-N, N-dimethylpropanamide (boiling point: 215 ° C.), 3-butoxy-N, N-dimethylpropanamide (boiling point: 252 ° C.) ), N-Methyl-2-pyrrolidone (boiling point: 204 ° C), γ-butyrolactone (boiling point: 204 ° C), cyclohexanone (boiling point: 156 ° C), cyclopentanone (boiling point: 131 ° C), butyl acetate (boiling point: 126 ° C) ° C.), methylisobutylketone (boiling point: 118 ° C.), methylethylketone (boiling point: 79.6 ° C.), toluene (boiling point: 111 ° C.).
Among these, as a combination of two kinds of liquid dispersion media having different boiling points, which are suitable for the present dispersion B and have a relationship of forming an azeotropic mixture, water and methyl ethyl ketone, water and cyclohexanone, ethylene glycol and toluene, and toluene are used. And N, N-dimethylformamide. In the present specification, the combination of toluene and N, N-dimethylformamide is regarded as an azeotropic mixture having an azeotropic point of 59.9 to 109.9 ° C.

The present dispersion B may further contain another liquid dispersion medium different from the above two types of liquid dispersion media as long as the effect of the present invention is not impaired.
Here, the other liquid dispersion medium may have a relationship of forming an azeotropic mixture with at least one of the two types of liquid dispersion medium, or may be azeotropically heated in a three-component system together with the two types of liquid dispersion medium. The relationship may be such that a mixture is produced, but it is preferable that the relationship does not produce any azeotropic mixture.
In the present dispersion B, the total content of the liquid dispersion medium is preferably 30 to 90% by mass, more preferably 50 to 80% by mass.

The present dispersion B may or may not further contain a surfactant. Examples of the surfactant include those similar to those described above in the description of the present dispersion A. The dispersion B preferably does not contain a fluorine-based surfactant.

The present dispersion liquid B may further contain another resin material in addition to the present particles from the viewpoint of improving the adhesiveness and low linear expansion property of the molded product formed from the present dispersion liquid B. Even in such a case, the present dispersion B tends to have excellent dispersion stability. When the present dispersion B contains another resin material, the content thereof is preferably 40% by mass or less with respect to the entire present dispersion B.
Examples of other resin materials include tetrafluoroethylene polymers other than F polymers, F polymers, and aromatic polymers. Another resin material may be the same as the F polymer in the particles.
Tetrafluoroethylene-based polymers other than F polymers include polytetrafluoroethylene (PTFE), polymers containing TFE units and units based on ethylene, polymers containing TFE units and units based on propylene, TFE units and fluoroalkylethylene. Examples include polymers containing based units, polymers containing TFE units and units based on chlorotrifluoroethylene.
The F polymer may be the same type of polymer as the F polymer constituting the particles described above, or may be a different kind of polymer. Among them, PTFE or F polymer is preferable, PFA or FEP is more preferable, and the above-mentioned polymer (1) or polymer (2) is further preferable.
The F polymer is preferably in the form of particles, and is preferably dispersed in the present dispersion B. Further, the particles of the F polymer may be composed of only the F polymer, or may contain the F polymer and other components (such as the resin material described above).

Examples of the aromatic polymer include the same aromatic polymers that may be contained in the dispersion liquid A, and the preferable range thereof is also the same.

The dispersion liquid B may further contain inorganic particles in addition to the inorganic particles contained in the particles. Examples of the inorganic particles include those similar to the inorganic particles that the dispersion liquid A may further contain, and the preferred embodiments thereof are also the same.
In addition to the above components, the dispersion B may further contain other components similar to those described in the description of the dispersion A, as long as the effects of the present invention are not impaired.

The present dispersion B can be prepared in the same manner as the present dispersion A.
The preferable ranges of the content of the particles, the content of the F polymer, and the mass ratio of the F particles to the inorganic substances in the particles are the same as those in the dispersion A.
The content of the F polymer in the dispersion B is preferably 40% by mass or more, more preferably 50% by mass or more.
When the present dispersion B contains the F polymer as another resin separately from the F polymer contained in the present particles, the content of the F polymer in the present dispersion B is the content of the F polymer contained in the present particles. It means the sum of the contents of the F polymer contained as another resin.

The preferable range of the viscosity, thixotropic ratio, and component sedimentation rate of the present dispersion B is the same as the preferable range of the viscosity, thixotropy of the present dispersion A.

When the dispersion liquid B is brought into contact with the surface of the base material layer and heated to form a polymer layer containing an F polymer and an inorganic substance, a laminate having the base material layer and the polymer layer can be obtained.
The details of the method for manufacturing the laminate, the base material layer, the printed circuit board using the laminate, and the embodiments of the multilayer printed circuit board are the same as those described above in the description of the dispersion liquid A, including the preferred embodiments.

When drying the liquid film, the liquid film is heated at a temperature at which the dispersion medium volatilizes, and the dry film is formed on the surface of the sheet base material. The heating temperature is preferably azeotropic point + 50 ° C. or lower, and more preferably azeotropic point or lower, of the azeotropic mixture of the two types of dispersion media contained in the dispersion liquid B. The drying temperature is preferably 120 ° C to 200 ° C.

The composite particle of the present invention has a melting temperature of 260 to 320 ° C., contains F polymer containing 1 to 5 mol% of PAVE units with respect to all units, and silica, and is measured by X-ray photoelectron spectroscopy. It is a composite particle (hereinafter, also referred to as “this particle α”) in which the amount of silicon atom is 1 or more with respect to the amount of fluorine atom on the surface of the particle.

The particles α are a highly stable composite of F polymer and silica whose physical properties such as polarity can be adjusted. The mechanism of action is not always clear, but it is thought to be as follows.
The F polymer not only has excellent shape stability such as fibril resistance, but also has a highly flexible conformation in which restrictions on molecular motion are relaxed at the single molecule level. Such F-polymers tend to form microspherulites at the molecular aggregate level, and microconcavo-convex structures are likely to be formed on the surface thereof. Therefore, it is considered that the molecular assembly of the F polymer physically adheres tightly to silica while remaining stable without damaging its shape. It is also considered that the interaction between the densely adhered silica further promotes the adhesion of silica and stabilizes the composite particles.
As a result, it is considered that the particles α have high stability while containing a relatively large amount of silica, and have the physical characteristics of the F polymer and the physical characteristics of silica.

The F polymer in the particles α is a TFE polymer having a melting temperature of 260 to 320 ° C. and containing 1 to 5 mol% of PAVE units with respect to all units. As the F polymer, the polymer (1) containing the above-mentioned TFE unit and PAVE unit and having a polar functional group is more preferable. If the F polymer is the polymer (1), the polymer (1) and silica are not only easily physically attached but also chemically easily attached in the particles α, and the above-mentioned mechanism of action is enhanced. It's easy to do.

The particles α may contain a polymer other than the F polymer. However, the ratio of the F polymer to the polymer contained in the particles α is preferably 80% by mass or more, more preferably 100% by mass.
Examples of the polymer other than the F polymer include heat-resistant resins such as aromatic polyester, polyamide-imide, thermoplastic polyimide, polyphenylene ether, and polyphenylene oxide.

The particles α contain silica. As the silica, one type may be used, or two or more types may be mixed and used. Further, an inorganic substance other than silica may be contained.
When other inorganic substances other than silica are contained, the total amount of silica and other inorganic substances is 100% by mass, and the content of silica is preferably 50% by mass or more, more preferably 75% by mass. The silica content is preferably 100% by mass or less, more preferably 90% by mass or less.

It is preferable that at least a part of the surface of silica is surface-treated. Examples of the surface treatment agent used for such surface treatment include compounds similar to those used for the surface treatment of the above-mentioned inorganic substances, and examples thereof include a silane coupling agent.

The specific surface area of the silica (BET method) is preferably 1 ~ ^20m 2 / g, more preferably 5 ~ ^8m 2 / g. In this case, the interaction between silica and the F polymer tends to be enhanced. Further, when the dispersion liquid containing the particles α is applied to the substrate to form the polymer layer, the silica and the F polymer are more uniformly distributed, and it is easy to balance the physical properties of both.

Silica includes silica filler ("Admafine (registered trademark)" series manufactured by Admatex), spherical fused silica ("SFP (registered trademark)" series manufactured by Denka), and hollow silica filler (Pacific cement). "E-SPHERES" series manufactured by Nittetsu Mining Co., Ltd., "Silicax" series manufactured by Nittetsu Mining Co., Ltd., "Ecocos Fire" series manufactured by Emerson & Cumming, hydrophobic AEROSIL series "RX200" manufactured by Nippon Aerosil Co., Ltd., etc.) Can be mentioned.
In addition, examples of the inorganic substances other than silica include the above-mentioned inorganic substances that may form the particles.

The shape of silica is preferably granular, preferably spherical, needle-shaped (fibrous), or plate-shaped (pillar). Specific shapes of silica include spherical, scale-like, layered, leaf-like, apricot kernel-like, columnar, chicken crown-like, equiaxed, leaf-like, mica-like, block-like, flat plate-like, wedge-like, rosette-like, and mesh-like. , Square column is mentioned, and spherical shape is preferable. When spherical silica is used, when the dispersion liquid containing the particles α is applied to the substrate to form a polymer layer, the silica and the F polymer are more evenly distributed, and its function is likely to be enhanced.
The spherical silica is preferably substantially spherical. The substantially spherical shape is as described above.

When the particles α are measured by X-ray photoelectron spectroscopy (hereinafter, also referred to as ESCA), the amount of silicon atoms with respect to the amount of fluorine atoms on the surface is 1 or more. ESCA is a method for quantifying the amount of elements present on the surface of particles and the like, and it is possible to quantify each element such as carbon (C), oxygen (O), fluorine (F), and silicon (Si). In the present invention, the surface is defined as a depth of 2 to 8 nm from the surface of the particles. At the time of measurement, the particles were fixed with carbon tape, and the particles were sampled so that the carbon tape was not exposed and the surface flatness was assured as much as possible. The information and analysis conditions of the device are as follows.
Analyzer: ESC A 5500 manufactured by ULVAC-PHI
X-ray source: Al Kα 14kV
Beam diameter: 800 μmφ
Measurement mode: Wide spectrum measurement Binding energy measurement range: 0 to 1100 eV
Path energy: 93.8 eV
Energy step: 0.8 eV
Accumulated number: 16 cycles
Neutralization gun: Used Detector and sample surface angle: 45 degrees In the present invention, the element existing at such a depth of the particle α is measured by ESCA, and the amount of silicon atom and the amount of fluorine atom are quantified. .. The particles α have a value of 1 or more obtained by dividing the amount of silicon thus quantified by the amount of fluorine.

In other words, the particles α having such a value are particles whose surface is highly coated with silica, and not only have excellent particle characteristics such as liquid dispersibility due to silica, but also contain the particles α. The molded product formed from the liquid composition tends to have the physical characteristics of silica and the physical characteristics of F polymer to a high degree.
The amount of silicon atoms with respect to the amount of fluorine atoms on the surface of the particles α obtained by measurement with ESCA is preferably 1.0 or more, more preferably 1.1 or more, still more preferably 1.2 or more. The amount of silicon atom with respect to the amount of fluorine atom is preferably 100 or less.

The target elements in ESCA measurement are four elements, carbon element, oxygen element, fluorine element and silicon element, and the ratio (unit: Atomic%) of each of the fluorine element and silicon element to the total is determined by each atom. The amount was taken.
In order to keep the amounts of fluorine atoms and silicon atoms on the surface of the particles α within the above range, it is preferable to prepare the particles α by the above-mentioned dry method A, dry method B, wet method, etc., and the dry method A is used. More preferred. That is, it is preferable that the F particles and silica collide with each other at a temperature equal to or higher than the melting temperature of the F polymer and in a suspended state to form the particles α.

The D50 of the particles α is preferably 40 μm or less, more preferably 10 μm or less, and even more preferably 4 μm or less. The D50 of the particles α is preferably 0.1 μm or more, more preferably 1 μm or more, still more preferably 2 μm or more.
The D90 of the particles α is preferably 40 μm or less, more preferably 4 μm or less.
If D50 and D90 of the particles α are within such a range, the dispersion stability of the particles α and the liquid composition containing the particles α are applied to the substrate to form a polymer layer (F layer). The dispersion uniformity in the polymer layer (F layer) of the laminated body is further enhanced, and it is easy to obtain a laminated body having the physical properties of the F polymer and the physical properties of silica to a high degree.

The larger the amount of silica in the main particles α, the smaller the bulk density of the main particles α, which is preferable. On the other hand, the smaller the amount of silica in the particles α, the smaller the viscosity of the liquid composition containing the particles α, which is preferable. From the above viewpoint, the amount of silica in the particles α is preferably 15 to 85 parts by mass with respect to 100 parts by mass of the F polymer. Within such a range, the amounts of the fluorine element and the silicon element on the surface of the particles α are likely to be within the above range. The amount of silica in the particles α is more preferably 20 parts by mass or more, still more preferably 30 parts by mass or more, based on 100 parts by mass of the F polymer. The amount of silica in the particles α is more preferably 70 parts by mass or less, still more preferably 50 parts by mass or less, based on 100 parts by mass of the F polymer.
Further, by setting the above range, the amounts of fluorine atoms and silicon atoms on the surface of the particle α can be easily set in the above range.

As a preferred embodiment of the particles α, an F polymer is used as a core, and silica is attached to the surface of the core, that is, the above-mentioned embodiment I is preferable.

In the case of the aspect I, it is preferable that the core of the F polymer and the silica are each in the form of particles. In this case, since silica having a hardness higher than that of the F polymer is exposed on the surface of the particles α, the fluidity is increased and the handleability thereof is likely to be improved.
In the case of the aspect I, the core of the F polymer may be composed of a single F particle or an aggregate of F particles.
The particles α of the aspect I are preferably produced by the dry method A or the dry method B described above, and the dry method A is more preferable. In this case, it is preferable to set the D50 of the F particles to be larger than the D50 of the silica particles and set the amount of the F particles to be larger than the amount of the silica particles. If the particles α are produced by the dry method A or the dry method B with such a relationship set, the particles α of the aspect I can be easily obtained.

The D50 of the silica particles is preferably 0.001 to 0.5, more preferably 0.01 to 0.05, based on the D50 of the F particles. Specifically, it is preferable that the D50 of the F particles is more than 1 μm and the D50 of the silica particles is 0.8 μm or less.
In the particle α of the aspect I thus obtained, the above relationship is maintained, the D50 of the core of the F polymer is larger than the D50 of the silica particles, and the mass of the F polymer occupying the D50 is larger than the mass of the silica. Become. In this case, the surface of the core of the F polymer is coated with a larger amount of silica particles so that the particles α of aspect I have a core-shell structure. Further, in this case, the aggregation of the F particles is suppressed, and it is easy to obtain the present particles α in which the silica particles are attached to the core composed of a single F particle.

In the aspect I, the silica particles are preferably spherical, and more preferably substantially true spherical. The substantially spherical shape is as described above.
By using such highly spherical silica particles, when the liquid composition containing the particles α is applied to the substrate to form a polymer layer, the silica and the F polymer are more evenly distributed, and both of them are distributed. It is easy to balance the physical properties of silica.

In the aspect I, the D50 of the silica particles is preferably in the range of 0.001 to 0.8 μm, more preferably 0.01 to 0.3 μm, still more preferably 0.03 to 0.1 μm. Silica in the range to which D50 is applied is sometimes referred to as nanosilica, and the handleability and fluidity of the particles α are likely to be improved, and the dispersion stability is likely to be improved. When silica in such a range is used, it becomes easy to adjust the liquid physical properties such as the viscosity and thixotropy of the liquid composition containing the particles α, and the handleability and defoaming property are easily excellent.
Further, the particle size distribution of the silica particles is preferably 3 or less, and more preferably 2.9 or less, using the value of D90 / D10 as an index. A narrow particle size distribution is preferable from the viewpoint of facilitating the control of the fluidity of the obtained particles α.

In the aspect I, it is preferable that at least a part of the surface of the silica particles is surface-treated, and it is more preferable that the silica particles are surface-treated with a silazane compound such as hexamethyldisilazane, a silane coupling agent, or the like. .. Examples of the silane coupling agent include the above-mentioned compounds.

In the aspect I, one kind of silica particles may be used, or two or more kinds of silica particles may be mixed and used. When two kinds of silica particles are mixed and used, the average particle diameter of each silica particle may be different from each other, and the mass ratio of the content of each silica particle can be appropriately set according to the desired function.

Further, in the case of the aspect I, it is preferable that a part of the silica particles is embedded in the core of the F polymer. As a result, the adhesion of the silica particles to the core of the F polymer is further improved, and the silica particles are less likely to fall off from the particles α. That is, the stability of the particles α is further improved.
In the particle α of the aspect I, the D50 of the core of the F polymer is preferably 0.1 μm or more, more preferably 1 μm or more, still more preferably 2 μm or more. D50 is preferably 30 μm or less, more preferably 10 μm or less, still more preferably 5 μm or less.

Further, the ratio of the F polymer to the main particles α of the aspect I is preferably 50% by mass or more, more preferably 60% by mass or more. The proportion of the F polymer is preferably 99% by mass or less, more preferably 90% by mass or less, still more preferably 80% by mass or less. The ratio of silica is preferably 1% by mass or more. 10% by mass or more is more preferable, and 20% by mass or more is further preferable. The ratio of silica is preferably 50% by mass or less, more preferably 40% by mass or less. Further, when silica in such a range is used, not only the particles α having excellent handleability and dispersion stability can be easily obtained, but also the liquid physical properties such as the viscosity and thixotropy of the liquid composition containing the particles α can be adjusted. Is easy, and its handleability and defoaming property are easy to be excellent.

The particles α of aspect I may be further surface-treated. Specific examples of such surface treatment are as described above, and not only the amount of surface silica of the particles α can be adjusted, but also the surface physical properties thereof can be further adjusted.

In the present invention, by mixing the present particles α and the dispersion medium, a liquid composition containing the present particles α and the dispersion medium and having the present particles α dispersed in the dispersion medium (hereinafter, also referred to as the present composition) can be obtained. Be done.
The particles α can exhibit a sufficiently high polarity and can be stably dispersed even if a large amount is added to the dispersion medium. Further, in the polymer layer, laminate, and film formed from the present composition, the F polymer and silica are more evenly distributed, and the physical properties of the F polymer such as electrical properties and adhesiveness and silica such as low linear expansion are achieved. It is highly easy to express the physical characteristics of the product.
The liquid dispersion medium in the present composition is a liquid compound that functions as a dispersion medium for the particles α and is inert at 25 ° C. The dispersion medium may be water or a non-aqueous dispersion medium. The dispersion medium may be one kind or two or more kinds. In this case, it is preferable that the different liquid compounds are compatible with each other.
Examples of the dispersion medium include the same as the liquid dispersion medium in the present composition A and the present composition B.

When the dispersion medium contains an aprotic polar solvent such as N-methyl-2-pyrrolidone, at least a part of the surface of the silica contained in the particles α is composed of an amino group, a vinyl group and a (meth) acryloyloxy group. It is preferably surface-treated with a silane coupling agent having at least one group selected from the group, and more preferably surface-treated with phenylaminosilane.
When the dispersion medium contains a non-polar solvent such as toluene, it is preferable that at least a part of the surface of the silica contained in the particles α is hydrophobized, and at least selected from the group consisting of an alkyl group and a phenyl group. It is preferably surface-treated with a silane coupling agent having one type of group.
When the dispersion medium contains a protic polar solvent such as water, the silica contained in the particles α is preferably not surface-treated.
In the case of the combination of such a dispersion medium and the surface treatment of silica, the present composition tends to be excellent in dispersion stability.

The content of the particles α in the composition is preferably 1 to 50% by mass, more preferably 10 to 40% by mass, with the composition as 100% by mass.
The content of the dispersion medium in the present composition is preferably 50 to 99% by mass, more preferably 60 to 90% by mass, with the present composition as 100% by mass.

The present composition may further contain a surfactant from the viewpoint of further improving the dispersion stability of the particles α and improving the particle sedimentation property and the handleability, but the particles α have the dispersion stability. Since it is excellent, it does not have to contain a surfactant practically. Examples of the surfactant include the above-mentioned surfactants.
The fact that the surfactant is substantially not contained means that the concentration of the surfactant in the present composition does not exceed 1% by mass, and the amount of the surfactant in the present composition is 1% by mass or less. Therefore, the amount of the surfactant is preferably 0.5% by mass or less, more preferably 0% by mass.

The viscosity of the present composition is preferably 50 mPa · s or more, more preferably 100 mPa · s or more. The viscosity of the present composition is preferably 50,000 mPa · s or less, preferably 1000 mPa · s or less, and more preferably 800 mPa · s or less. In this case, since the present composition is excellent in coatability, it is easy to form a molded product such as a polymer layer having an arbitrary thickness.
The thixotropy of the present composition is preferably 1.0 or more. The thixotropy of the present composition is preferably 3.0 or less, more preferably 2.0 or less. In this case, since the present composition is not only excellent in coatability but also excellent in homogeneity, it is easy to form a molded product such as a more dense polymer layer.

The present composition may further contain an F polymer, a polymer other than the F polymer, or a precursor thereof. Such polymers or precursors thereof include polytetrafluoroethylene (PTFE), polymers containing TFE units and PAVE units (PFA), polymers containing TFE units and units based on hexafluoropropylene (FEP), TFE units and the like. Polymers containing ethylene-based units (ETFE), polyvinylidene fluoride (PVDF), polyimides, polyallylates, polysulfones, polyallylsulfones, polyamides, polyetheramides, polyphenylene ethers, polyphenylene sulfides, polyallyl ether ketones, polyamideimides. , Liquid polymer, liquid crystal polyester amide, epoxy resin, maleimide resin and the like. The PFA may be an F polymer or a PFA other than the F polymer.
These polymers or precursors thereof may be dispersed or dissolved in the present composition. Further, these polymers or precursors thereof may be thermoplastic or thermosetting. The composition preferably contains the above-mentioned aromatic polymers.
In addition to the above components, the present composition may further contain other components similar to those described in the description of the present dispersion A, as long as the effects of the present invention are not impaired.

When the present composition is brought into contact with the surface of the base material layer and heated to form a polymer layer containing F polymer and silica, a laminate having the base material layer and the polymer layer can be obtained. The details of the method for manufacturing the laminate, the base material layer, the printed circuit board using the laminate, and the embodiments of the multilayer printed circuit board are the same as those described above in the description of the dispersion liquid A, including the preferred embodiments.

Further, a film can be produced by melt-kneading the particles α and the fluoroolefin polymer and then extrusion molding.
The particles α include an F polymer having a high interaction (compatibility) with a fluoroolefin polymer and silica. Further, since the particles α have silicon atoms in a predetermined ratio on the surface, they have a predetermined hardness, and when the particles α and the fluoroolefin polymer are melt-kneaded, the composite particles and the fluoroolefin polymer are used. Collide with each other, and each is easily crushed and atomized.
As a result, both are uniformly melt-kneaded, and in the obtained film, the F polymer, the fluoroolefin polymer and the silica are uniformly distributed, and the physical characteristics of the F polymer and the fluoroolefin polymer, particularly the electrical characteristics, and the silica are used. Physical properties such as low-line expansion are highly likely to occur.
The fluoroolefin polymer to be melt-kneaded with the particles α may be an F polymer or a polymer containing a unit based on a fluoroolefin other than the F polymer.

Examples of the fluoroolefin polymer include PTFE, PFA, FEP, ETFE and PVDF. The PFA may be an F polymer or a PFA other than the F polymer. The fluoroolefin polymer may be the same F polymer as the F polymer contained in the composite particles.
The melting temperature (melting point) of the fluoroolefin polymer is preferably 160 to 330 ° C.
The glass transition point of the fluoroolefin polymer is preferably 45 to 150 ° C.
Fluoroolefin-based polymers also preferably have polar functional groups. The types and introduction methods of the polar functional groups are the same as those in the above-mentioned F polymer, including suitable types and introduction methods.

The melt-kneading of the particles α and the fluoroolefin polymer is performed using, for example, a uniaxial kneader. The uniaxial kneader has a cylinder and one screw rotatably provided in the cylinder. If a uniaxial kneader is used, it is easy to prevent deterioration of the F polymer and the fluoroolefin polymer during melt kneading.
In this case, when the total length of the screw is L (mm) and the diameter is D (mm), the effective length (L / D) represented by the ratio of the total length L to the diameter D is preferably 30 to 45. When the effective length is within the above range, it is possible to apply sufficient shear stress to the F polymer and the TFE polymer while preventing deterioration, and it is easy to reduce the temperature unevenness of the melt-kneaded product.
The rotation speed of the screw is preferably 10 to 50 ppm.

The melt-kneaded product is discharged from a T-die arranged at the tip of the cylinder. After that, the melt-kneaded product discharged from the T-die comes into contact with a plurality of cooling rolls to be solidified and formed into a film. The obtained long film is wound on a take-up roll.
The thickness of the film is preferably 5 to 150 μm, more preferably 10 to 100 μm.
The shape of the film may be long or single-wafered. The length of the long film in the longitudinal direction is preferably 100 m or more. The upper limit of the length in the longitudinal direction is usually 2000 m. Further, the length of the long shape in the lateral direction is preferably 1000 mm or more. The upper limit of the length in the lateral direction is usually 3000 mm.

By superimposing the obtained film on the base material layer and then heat-pressing, a laminate having a polymer layer formed from the film and a base material layer can be obtained.
The conditions for the hot press are preferably 120 to 300 ° C., an atmospheric pressure of 20 kPa or less, and a press pressure of 0.2 to 10 MPa.
The embodiments of the substrate layer, the printed circuit board using the laminate, and the multilayer printed circuit board are the same as those in the above-mentioned method 1 including the preferred embodiments.
Further, the inflation film may be manufactured by using a round die instead of the T die.

Although the dispersion liquid, the composite particles and the method for producing the composite particles of the present invention have been described above, the present invention is not limited to the configuration of the above-described embodiment.
For example, the dispersion liquid and the composite particle of the present invention may be added to any other configuration or may be replaced with any configuration exhibiting the same function in the configuration of the above embodiment, respectively.
In addition, the method for producing composite particles of the present invention may additionally have any other step in the configuration of the above embodiment, or may be replaced with any step that produces the same action. ..

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.
Details of each component are shown below.
[F particles]
F particle 1: F polymer 1 having an acid anhydride group (melting temperature 300 ° C.) containing 97.9 mol%, 0.1 mol%, and 2.0 mol% of TFE unit, NAH unit, and PPVE unit in this order. Particles consisting of (D50: 2 μm, bulk density: 0.18 g / m ² )
F particle 2: Particle (D50: 2 μm, bulk) composed of F polymer 2 having no functional group (melting temperature 305 ° C.) containing 97.5 mol% and 2.5 mol% of TFE unit and PPVE unit in this order. Density: 0.19 g / m ² )
^{F particle 3: Particles (D50: 2 μm, bulk density: 0.19 g / m 2} ) composed of F polymer 3 (melting temperature 305 ° C.) consisting only of TFE units and PPVE units.
F particle 4: Particles (D50) composed of F polymer 4 (melting temperature: 300 ° C.) containing 97.5 mol% and 2.5 mol% of TFE units and PPVE units in this order and having no polar functional group. : 2.6 μm)
[PTFE particles]
PTFE1: Particles made of non-heat-meltable PTFE (D50: 0.3 μm, bulk density: 0.2 g / m ² )
PTFE2: Particles composed of fibrilous PTFE (D50: 2.4 μm)
[Inorganic matter]
Inorganic 1: Silica filler (similar spherical shape, average particle size 0.03 μm), surface-treated with silane coupling agent [silica particles]
Silica particles 1: Approximately spherical particles made of silica (D50: 0.05 μm)
Silica particles 2: Approximately spherical particles made of silica (D50: 0.25 μm)
[Dispersion medium]
NMP: N-methyl-2-pyrrolidone dispersion medium S1: toluene (boiling point: 111 ° C)
Dispersion medium S2: N, N-dimethylformamide (DMF) (boiling point: 153 ° C)
[Aromatic polymer]
Polymer 1: A varnish in which a thermoplastic aromatic polyimide (PI1) is dissolved in NMP Polymer 2: 2-hydroxy-6-naphthoic acid, 4,4'-dihydroxybiphenyl and terephthalic acid, and 2,6-naphthalenedicarboxylic acid. A powder (D50: 16 μm) obtained by pulverizing a thermoplastic polymer obtained by reacting in this order at a ratio of 60 mol%, 20 mol%, 15.5 mol%, and 4.5 mol%.
Polymer 3: Thermosetting aromatic bismaleimide powder (D50: 2 μm)

[Example 1-1]
1. 1. Preparation of Composite Particles A mixture of 99 parts by mass of F particles 1 and 1 part by mass of an inorganic substance 1 was prepared.
Next, a powder processing device (hybridization system) that applies stress by sandwiching the particles between the inner wall of the container and the agitator while stirring the particles with a stirring blade that rotates at high speed in a cylindrical container. , The mixture was charged. Then, the F particles 1 and the inorganic substance 1 were made to collide with each other while being suspended in an atmosphere of high temperature turbulence, and a stress was applied between them to perform a composite treatment. The inside of the apparatus during the treatment was kept at a temperature of 100 ° C. or lower under a nitrogen atmosphere, and the treatment time was set to 15 minutes.
The obtained processed product was in the form of fine powder. Further, as a result of analyzing this fine particle with an optical microscope, it was a composite particle 1 having a core-shell structure in which F particle 1 was used as a core and an inorganic substance 1 was attached to the surface of the core to form a shell.
The shape of the composite particle 1 was spherical, and its D50 was 4 μm.

2. 2. Production and Evaluation of Dispersion NMP and Polymer 1 were added to a tank equipped with a stirring blade, and the inside of the tank was sufficiently stirred. Next, the obtained composite particles 1 were added to the tank, stirred at 800 rpm for 15 minutes, and sheared in a state where an ascending flow was formed, and the composite particles 1 (100 parts by mass) and the polymer 1 (30 parts by mass) were subjected to shearing treatment. ) And NMP (120 parts by mass) were obtained. The viscosity of the obtained dispersion liquid 1 at 25 ° C. was 18,000 mPa · s. The dispersion stability and the erythrocyte sedimentation rate of the dispersion liquid 1 were evaluated according to the following criteria.
<Evaluation criteria for dispersion stability>
〇: There is little foaming and no agglomerates are observed both immediately after preparation and after storage, and they are uniformly dispersed. Δ: Some agglomerates are observed both immediately after preparation and after storage. <Evaluation criteria for component sedimentation rate>
◯: The erythrocyte sedimentation rate is 60% or more.
Δ: The erythrocyte sedimentation rate is more than 40% and 60% or less.
X: The erythrocyte sedimentation rate is 40% or less.

3. 3. Preparation and Evaluation of Laminate A wet film was formed by applying the dispersion liquid 1 to the surface of a long copper foil (thickness 18 μm) using a bar coater. Next, the copper foil on which the wet film was formed was passed through a drying oven at 110 ° C. for 5 minutes and dried by heating to obtain a dry film. Then, the dry membrane was heated at 380 ° C. for 3 minutes in a nitrogen oven. As a result, a laminate 1 having a copper foil and a polymer layer (thickness 20 μm) as a molded product containing a melt-fired product of F particles 1, an inorganic substance 1 and a polymer 1 on the surface thereof was prepared.
A 180 mm square test piece was cut out from the laminate 1, and the linear expansion coefficient of the test piece was measured for the test piece in the range of 25 ° C. or higher and 260 ° C. or lower according to the measurement method specified in JIS C 6471: 1995. It was evaluated according to the criteria of.
<Evaluation criteria for coefficient of linear expansion>
〇: The coefficient of linear expansion is 50 ppm / ° C or less.
Δ: The coefficient of linear expansion is more than 50 ppm / ° C. and 75 ppm / ° C. or less.
X: The coefficient of linear expansion is over 75 ppm / ° C.

[Example 1-2]
A mixture of 99 parts by mass of F particles 1 and 1 part by mass of an inorganic substance 1 was prepared.
Next, the mixture was put into a powder processing apparatus (mechanofusion apparatus) including a cylindrical rotating body having a receiving surface on the inner peripheral surface and an inner piece arranged at a short distance from the receiving surface. After that, the cylindrical rotating body was rotated at high speed around the central axis. The centrifugal force generated at this time pressed the particles against the receiving surface, introduced the mixture into the narrow space (pressing space) between the receiving surface and the inner piece, and collided the particles in a sheared state for treatment. The temperature of the atmosphere of the cylindrical rotating body during the treatment was maintained at 100 ° C. or lower, and the treatment time was set to 15 minutes.
The obtained processed product was in the form of fine powder. Further, as a result of analyzing this fine particle with an optical microscope, it was found that the composite particle 2 had a core-shell structure in which the F particle 1 was used as a core and the inorganic substance 1 adhered to the surface of the core to form a shell.
The shape of the composite particle 2 was spherical, and its D50 was 18 μm.
Using the obtained composite particles 2, a dispersion liquid 2 was produced in the same manner as in Example 1-1, and a laminate 2 was prepared and evaluated. The evaluation results are shown in Table 1.

[Example 1-3 to Example 1-8]
Composite particles 3 and 4 and dispersions 3 to 8 were obtained in the same manner as in Example 1-1 except that the type and amount of each component were changed as shown in Table 1 below, and laminated bodies 3 to 8 were produced. Table 1 shows the evaluation results of the obtained dispersion liquid and the laminate.

[Example 2-1]
1. 1. Production of Composite Particles A mixture of 99 parts by mass of F particles 1 and 1 part by mass of an inorganic substance 1 was prepared, and 1. of Example 1-1. The composite particle 1 was obtained in the same manner as above. The shape of the composite particle 1 was spherical, and its D50 was 4 μm.

2. 2. Production and Evaluation of Dispersion Solution The dispersion medium S1 (toluene), the dispersion medium S2 (DMF), and the composite particle 1 obtained above were added to a tank equipped with a stirring blade and stirred at 800 rpm for 15 minutes to obtain the composite particle 1 (composite particle 1 (toluene). A dispersion 9 containing 100 parts by mass), toluene (30 parts by mass) and DMF (70 parts by mass) was obtained. The viscosity of the obtained dispersion liquid 9 at 25 ° C. was 13000 mPa · s.
The dispersion stability of the dispersion liquid 9 is described in 2. of Example 1-1. It was evaluated in the same way as.

3. 3. Preparation and Evaluation of Dry Film and Laminate A wet film was formed by applying the dispersion liquid 9 to the surface of a long copper foil (thickness 18 μm) using a bar coater. Next, the metal foil on which the wet film was formed was passed through a drying oven at 100 ° C. for 5 minutes and dried by heating to obtain a dry film 1.
The smoothness of the dry film 1 was visually evaluated according to the following criteria.
<Smoothness of dry film>
〇: The entire surface is smooth.
Δ: Unevenness due to lack of agglomerates or powder is visible on the edge of the surface.
X: Unevenness due to lack of agglomerates or powder is visible on the entire surface.

The metal foil having the dry film 1 is further heated in a nitrogen oven at 380 ° C. for 3 minutes, and the metal foil and a polymer layer containing the melt-fired product of F particles 1 and the inorganic substance 1 and the polymer 1 on the surface thereof. A laminated body 1 having (thickness 20 μm) was prepared. This polymer layer was excellent in surface smoothness without any agglomerates or irregularities due to foaming.

[Example 2-2 to Example 2-5]
Composite particles 5 and dispersions 10 to 13 were obtained in the same manner as in Example 2-1 except that the type and amount of each component were changed as shown in Table 2 below, and dry films 2 to 5 were produced. Table 2 shows the evaluation results of the obtained dispersion liquid and dry membrane.

[Example 3-1]
1. 1. Preparation of Composite Particles A mixture of 70 parts by mass of F particles 1 and 30 parts by mass of silica particles 1 was prepared.
Next, a powder processing device (hybridization system) that applies stress by sandwiching particles between the inner wall of the container and the stirring blade while stirring the particles with a stirring blade that rotates at high speed in a cylindrical container (hybridization system). The mixture was added to (registered trademark)). Then, the F particles 1 and the silica particles 1 were made to collide with each other while being suspended in an atmosphere of high temperature turbulence, and a stress was applied between them to perform a composite treatment. The temperature inside the apparatus during the treatment was kept at 120 ° C. or lower under a nitrogen atmosphere, and the compounding treatment time was set to 15 minutes.
As a result of analyzing the obtained fine particles with an optical microscope, a granular F polymer 1 was used as a core, and silica particles 1 were attached to the surface of the core to form a shell. Spherical composite particles 6 having a core-shell structure. It was (D50: 3 μm).

2. 2. Surface measurement of composite particles by ESCA ESCA5500 manufactured by ULVAC-PHI was used for surface measurement by ESCA. A monochromatic AlKα ray is used as the X-ray source at 14 kV, and a neutralization gun using an ion gun and a barium oxide emitter is used to prevent charging of the sample surface, while the photoelectron detection area is 800 μmφ, the photoelectron detection angle is 45 degrees, and the pass. The energy was 93.8 eV, the energy step was 0.8 eV / step, and the integrated number was 16 cycles. In addition, the content ratio of fluorine atoms was calculated from various peak intensities (C1s, O1s, F1s and Si2s orbitals) detected by measurement. The depth from the surface was determined based on the sputtering rate of the _{SiO 2} sputtering film using C60 ions as the sputtering ions. Table 3 shows the amount of silicon atoms (hereinafter, also referred to as “Si / F amount”) with respect to the amount of fluorine atoms on the surface of each composite particle.

3. 3. Evaluation 3-1. Evaluation of Dispersion Stability The composite particles 6 and NMP were added to the container, and the inside of the container was stirred without adding a surfactant to prepare a liquid composition 1 in which the composite particles 6 were dispersed. The liquid composition 1 was left to stand for a predetermined time, and its dispersion stability was evaluated according to the following criteria.
[Evaluation criteria]
〇: Foaming was suppressed during the preparation, and no sediment was formed even after standing at 25 ° C. for 3 days after the preparation.
Δ: There was foaming during preparation, but no sediment was formed even after standing at 25 ° C. for 3 days after preparation.
X: After standing at 25 ° C. for 3 days, sediment was formed.

3-2. Evaluation of Powder Falling and Warpage Liquid Composition 1 was applied to the surface of a long copper foil (thickness 18 μm) using a bar coater to form a liquid film. Next, the copper foil on which the liquid film was formed was passed through a drying oven at 120 ° C. for 5 minutes and dried by heating to obtain a dry film. Then, the dry film was heated at 380 ° C. for 3 minutes in a nitrogen oven. As a result, a laminate having a copper foil and a polymer layer containing a melt-fired polymer and silica on the surface thereof was obtained.

The powder removal of the dry film and the warp of the laminated body were evaluated.
The powder falling off of the dry film was evaluated by visually confirming the edge of the dry film and according to the following criteria.
[Evaluation criteria for powder drop]
〇: No chipping was confirmed at the edge of the dry film.
Δ: A part of the edge of the dry film was found to be missing.
X: A defect was confirmed in a wide range of the edge of the dry film.

The copper foil of the laminate was removed by etching with an aqueous solution of ferric chloride to prepare a single polymer layer. A 180 mm square test piece was cut out from the polymer layer, and the test piece was measured by the measuring method specified in JIS C 6471: 1995 and evaluated according to the following criteria.
[Evaluation criteria for warpage]
◯: The coefficient of linear expansion was less than ± 20 ppm / ° C.
Δ: The coefficient of linear expansion was ± 20 ppm / ° C or higher and less than ± 30 ppm / ° C.
X: The coefficient of linear expansion was ± 30 ppm / ° C. or higher.
The above evaluation results are shown in Table 4.

[Example 3-2 to Example 3-5]
Composite particles 7 to 10 were obtained in the same manner as in Example 3-1 except that the types and amounts of the particles were changed as shown in Table 1, and the liquid compositions 2 to 5 were prepared using the composite particles 7 to 10. did. Further, each of the liquid compositions 2 to 5 was used to obtain a laminate. Tables 3 and 4 show the surface measurement results of the composite particles, the dispersion stability of each liquid composition, the powder falling of the dry film, and the evaluation results of the warp of the laminated body.

The dispersion liquid of the present invention has excellent dispersion stability and can be easily processed into films, fiber-reinforced films, prepregs, and metal laminated plates (metal foils with resin). The obtained processed article can be used as a material for antenna parts, printed circuit boards, aircraft parts, automobile parts, sports equipment, food industry goods, slip bearings and the like.
Further, the composite particle of the present invention is excellent in handleability and dispersion stability in a dispersion medium. The liquid composition containing the composite particles of the present invention can be used for producing a molded product (laminate, film, etc.) having physical characteristics based on F polymer and characteristics based on silica. The molded product formed from the composite particles of the present invention is useful as an antenna component, a printed substrate, an aircraft component, an automobile component, a sports tool, a food industry article, a paint, a cosmetic, and the like, and specifically, a wire coating. Materials (aircraft wires, etc.), electrical insulating tapes, insulating tapes for oil drilling, materials for printed substrates, separation membranes (precision filtration membranes, ultrafiltration membranes, reverse osmosis membranes, ion exchange membranes, dialysis membranes, gas separation membranes) Etc.), electrode binders (for lithium secondary batteries, fuel cells, etc.), copy rolls, furniture, automobile dashboards, covers for home appliances, sliding members (load bearings, sliding shafts, valves, bearings, gears, cams, etc.) , Belt conveyor, food transport belt, etc.), tools (shovel, razor, cutting, saw, etc.), boiler, hopper, pipe, oven, baking mold, chute, die, toilet bowl, container covering material.

Claims (15)

It contains composite particles containing a tetrafluoroethylene-based polymer having a melting temperature of 260 to 320 ° C. and an inorganic substance, an aromatic polymer, and a liquid dispersion medium, and the composite particles are dispersed in the liquid dispersion medium. A dispersion having a viscosity at 25 ° C. of 1000 to 100,000 mPa · s. The tetrafluoroethylene-based polymer contains a unit based on perfluoro (alkyl vinyl ether) and has a polar functional group, or a tetrafluoroethylene-based polymer having a polar functional group, or 2.0 to 2.0 to all units based on perfluoro (alkyl vinyl ether). The dispersion according to claim 1, which is a tetrafluoroethylene-based polymer containing 5.0 mol% and having no polar functional group. The dispersion liquid according to claim 1 or 2, wherein the inorganic substance is silica. The dispersion liquid according to any one of claims 1 to 3, wherein the content of the aromatic polymer is less than the content of the composite particles. Any one of claims 1 to 4, wherein the aromatic polymer is at least one selected from the group consisting of aromatic polyimide, aromatic polyamide, aromatic polyamideimide, polyphenylene ether, liquid crystal polyester, and aromatic maleimide. The dispersion according to item 1. A dispersion liquid containing a complex particle containing a tetrafluoroethylene-based polymer having a melting temperature of 260 to 320 ° C. and an inorganic substance, and a liquid dispersion medium, wherein the composite particle is dispersed in the liquid dispersion medium, and is the liquid. A dispersion liquid in which the dispersion medium contains two types of liquid dispersion media having different boiling points, and the two types of liquid dispersion media are in a relationship of producing a eutectic mixture. The tetrafluoroethylene-based polymer contains a unit based on perfluoro (alkyl vinyl ether) and has a polar functional group, or a tetrafluoroethylene-based polymer having a polar functional group, or 2.0 to 2.0 to all units based on perfluoro (alkyl vinyl ether). The dispersion liquid according to claim 6, which is a tetrafluoroethylene-based polymer containing 5.0 mol% and having no polar functional group. The mixing amount ratio of the dispersion medium having a high boiling point in the two types of liquid dispersion media having different boiling points is the composition ratio (mass ratio) of the dispersion medium having a high boiling point in the azeotropic mixture of the two types of liquid dispersion media. The dispersion according to claim 6 or 7, which is more than the above. The dispersion liquid according to any one of claims 6 to 8, wherein at least one of the two types of liquid dispersion media having different boiling points constituting the liquid dispersion medium is water, alcohol or amide. It contains a tetrafluoroethylene polymer having a melting temperature of 260 to 320 ° C. and containing 1 to 5 mol% of units based on perfluoro (alkyl vinyl ether) with respect to all units, and silica, and is subjected to X-ray photoelectron spectroscopy. A composite particle in which the amount of silicon atoms is 1 or more with respect to the amount of fluorine atoms on the surface to be measured. The composite particle according to claim 10, wherein the average particle size is 2 μm or more and 10 μm or less. The composite particle according to claim 10 or 11, wherein the silica is 15 to 85 parts by mass with respect to 100 parts by mass of the tetrafluoroethylene polymer. The composite particle according to any one of claims 10 to 12, which has the tetrafluoroethylene polymer as a core and the silica on the surface of the core. The composite particle according to any one of claims 10 to 13, wherein the tetrafluoroethylene polymer is a tetrafluoroethylene polymer having a polar functional group. According to any one of claims 10 to 14, the particles of the tetrafluoroethylene-based polymer and the silica are collided with each other at a temperature equal to or higher than the melting temperature of the tetrafluoroethylene-based polymer and in a suspended state to obtain the composite particles. The method for producing a composite particle according to the above.