WO2021112164A1

WO2021112164A1 - Dispersion liquid, method for producing dispersion liquid, and molded article

Info

Publication number: WO2021112164A1
Application number: PCT/JP2020/044992
Authority: WO
Inventors: 渉笠井; 穂波財前; 敦美山邊
Original assignee: Ａｇｃ株式会社
Priority date: 2019-12-06
Filing date: 2020-12-03
Publication date: 2021-06-10
Also published as: CN114729171A; KR20220113354A; JPWO2021112164A1; TW202130732A; CN114729171B

Abstract

[Problem] To provide a dispersion liquid containing a prescribed tetrafluoroethylene-based polymer and a prescribed anisotropic filler, a method for producing the dispersion liquid, and a molded article highly endowed with the physical properties of the two materials. [Solution] This dispersion liquid contains a powder of a tetrafluoroethylene-based polymer including units based on a perfluoro(alkylvinylether) and units based on hexafluoropropylene, an anisotropic filler having a Mohs hardness of 4 or lower, and a liquid dispersion medium. The average particle size of the powder is smaller than the average particle size of the anisotropic filler. This molded article contains a prescribed tetrafluoroethylene-based polymer including units based on a perfluoro(alkylvinylether), and the anisotropic filler. The proportion of the anisotropic filler in the molded article is 10 mass% or greater.

Description

Dispersion liquid, manufacturing method of dispersion liquid and molded product

The present invention relates to a dispersion liquid containing a predetermined anisotropic filler, a method for producing the same, and a molded product.

Heat-meltable fluoropolymers such as tetrafluoroethylene-based polymers (PFA) containing units based on perfluoro (alkyl vinyl ether) and tetrafluoroethylene-based polymers (FEP) containing units based on hexafluoropropylene are releasable and electrically charged. It has excellent physical properties such as insulation, water and oil repellency, chemical resistance, weather resistance, and heat resistance, and is used after being processed into various molded products.
Patent Document 1 describes an electric wire tube having excellent electrical insulation, which is obtained by melt-kneading a dry blend of PFA powder and a boron nitride filler and extrusion molding.

Japanese Unexamined Patent Publication No. 2014-224228

However, the melt viscosity of such a fluoropolymer is generally high, and a strong stress is required when the fluoropolymer and the filler are melt-kneaded. At that time, the original properties of the filler (particularly, physical properties such as shape and surface condition) are impaired, and the physical properties of the filler tend to deteriorate in the molded product. The present inventors have found that such a tendency becomes remarkable in the case of a brittle filler having a low hardness, particularly in the case of a filler having a low hardness and an anisotropic property.
The present inventors have diligently studied to obtain a material suitable for molding such a molded product without using melt kneading. As a result, it was found that the dispersion liquid containing the predetermined fluoropolymer powder and the predetermined anisotropic filler is excellent in dispersion stability and also excellent in handleability such as coatability. Furthermore, it was also found that the molded product formed from the molded product is not easily impaired by the inherent properties of the anisotropic filler and has a high degree of physical properties of both.
An object of the present invention is to provide such a dispersion and a molded product.

The present invention has the following aspects.
[1] A tetrafluoroethylene polymer powder containing a unit based on perfluoro (alkyl vinyl ether) or a unit based on hexafluoropropylene, an anisotropic filler having a Mohs hardness of 4 or less, and a liquid dispersion medium are included. A dispersion liquid in which the average particle size of the powder is smaller than the average particle size of the anisotropic filler.
[2] The dispersion liquid of [1], wherein the content of the tetrafluoroethylene polymer and the content of the anisotropic filler are 5% by mass or more, respectively.
[3] The dispersion liquid of [1] or [2], wherein the anisotropic filler has a scaly or plate shape.
[4] The dispersion liquid according to any one of [1] to [3], wherein the anisotropic filler has an aspect ratio of 2 or more.
[5] The dispersion liquid according to any one of [1] to [4], wherein the anisotropic filler is an anisotropic filler containing boron nitride or talc.
[6] The dispersion liquid according to any one of [1] to [5], further containing a powder of polytetrafluoroethylene or an aromatic polymer.
[7] The dispersion liquid according to any one of [1] to [6], wherein the component dispersion layer ratio is 60% or more.
[8] A method for producing the dispersion liquid according to any one of [1] to [7], wherein the powder, the anisotropic filler, and an inorganic filler having an average particle size smaller than that of the anisotropic filler are used. A method for producing a dispersion liquid, which is mixed with a liquid dispersion medium.
[9] The production method of [8], wherein the mixing is carried out by stirring.
[10] A molded product containing a tetrafluoroethylene polymer containing a unit based on perfluoro (alkyl vinyl ether) and an anisotropic filler having a Mohs hardness of 4 or less.
The tetrafluoroethylene-based polymer contains 2.0 to 5.0 mol% of the polymer having a polar functional group or the unit based on the perfluoro (alkyl vinyl ether) with respect to all the units, and has no polar functional group. A molded product which is a polymer and in which the ratio of the anisotropic filler to the molded product is 10% by mass or more.
[11] The molded product of [10], wherein the anisotropic filler has an aspect ratio of 2 or more.
[12] The molded product of [11], wherein the anisotropic filler is a scaly anisotropic filler containing boron nitride or a plate-shaped anisotropic filler containing talc.
[13] The molded product according to any one of [10] to [12], wherein the anisotropic filler has an average particle size of 1 μm or more.
[14] The molded product according to any one of [10] to [13], further comprising polytetrafluoroethylene or an aromatic polymer.
[15] The molded product according to any one of [10] to [14], wherein the molded product is a layered molded product having a thickness of 150 μm or less.

According to the present invention, a dispersion liquid containing a predetermined fluoropolymer powder and a predetermined anisotropic filler and having excellent dispersibility and handleability can be obtained. In addition, a molded product having both physical characteristics and having particularly excellent electrical characteristics can be obtained.

The following terms have the following meanings.
The "average particle size (D50)" is a volume-based cumulative 50% diameter of the object (powder or filler) determined by the 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, measured in the same manner.
The "particle size distribution" is a distribution shown by a curve plotting the amount of particles (%) in each particle size interval obtained in the same manner.
The "melting temperature" 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" is a value measured by analyzing a polymer by a dynamic viscoelasticity measurement (DMA) method.
The "unit" in the polymer may be an atomic group formed directly from the monomer by the polymerization reaction, and the polymer obtained by the polymerization reaction is treated by a predetermined method to convert a part of the structure. May be. The unit based on monomer A contained in the polymer is also simply referred to as "monomer A unit".

The dispersion liquid of the present invention (hereinafter, also referred to as “the present dispersion liquid”) includes a unit (PAVE unit) based on perfluoro (alkyl vinyl ether) (PAVE) or a unit (HFP unit) based on hexafluoropropylene (HFP). It contains a powder of a tetrafluoroethylene polymer (hereinafter, also referred to as “F polymer”) (hereinafter, also referred to as “F powder”), an anisotropic filler having a moth hardness of 4 or less, and a liquid dispersion medium. ..
Further, the average particle size of the F powder is smaller than the average particle size of the anisotropic filler. In this dispersion, the F powder and the anisotropic filler are dispersed.
This dispersion is excellent in dispersion stability and handleability, and it is easy to form a molded product having highly physical properties of the F polymer and the anisotropic filler. The reason is not always clear, but it can be considered as follows.

It can be said that the anisotropic filler in the present invention is a fragile filler having an indefinite shape and various properties (crystal habit, etc.). In this dispersion, the anisotropic filler is unstable in its state and tends to aggregate or settle. Further, the anisotropic filler is in a state in which its shape or properties are easily broken by physical stress (shear stress or the like).
On the other hand, the F polymer is a polymer having plasticity typified by hot melt processability, and its powder (F powder) is not easily affected by physical stress and is excellent in its dispersibility.
This dispersion contains the F powder in a state smaller than the average particle size of the anisotropic filler, in other words, densely, and the affinity between the anisotropic filler and the F powder is relatively increased. It is in an easy state. That is, in this dispersion, since the F powder is contained more finely and densely, it is considered that pseudo secondary particles are likely to be formed between the F powder and the anisotropic filler. As a result, the dispersed state of the anisotropic filler is stabilized, and thus this dispersion is considered to be excellent in dispersion stability and handleability.

Further, if the F powder is melt-fired while removing the liquid dispersion medium from the present dispersion, it is easy to mold the molded product while suppressing the deformation of the anisotropic filler. Further, in the process of removing the liquid dispersion medium, it is easy to obtain a highly packed molded product while the anisotropic filler is oriented. As a result, it is considered that a molded product having the physical characteristics of the F polymer and the physical characteristics of the anisotropic filler was obtained from the present dispersion.
For example, when a molded product is formed from this dispersion containing a scaly or plate-shaped anisotropic filler, the anisotropic filler is oriented parallel to the surface (plane direction) of the molded product and is anisotropic in the molded product. The physical properties of the sex filler are highly likely to be expressed. Therefore, if this dispersion is used, the physical characteristics of the F polymer and the physical characteristics of the anisotropic filler can be highly expressed even in a thin-layered molded product.

Further, if the anisotropic filler is scaly or plate-shaped, the anisotropic filler forms a card house structure, which not only improves the liquid physical characteristics (viscosity, dispersion stability, etc.) of the dispersion liquid, but also improves the liquid properties (viscosity, dispersion stability, etc.). Anisotropic fillers are more likely to disperse in the moldings formed from it. As a result, the molded product tends to have excellent electrical characteristics. Further, when the molded product receives stress, the stress is easily dispersed by the anisotropic filler, and the mechanical strength (bending property, etc.) is easily improved. Further, since the anisotropic filler path is formed in the molded product, the thermal conductivity of the molded product is likely to be improved.

The F powder in this dispersion is preferably composed of an F polymer. The content of the F polymer in the powder is preferably 80% by mass or more, more preferably 100% by mass.
Other components that can be contained in the F powder include resins or inorganic substances different from the F polymer. Different resins include aromatic polyesters, polyamide-imides, thermoplastic polyimides, polyphenylene ethers, polyphenylene oxides.
Examples of the inorganic substance include silicon oxide (silica), metal oxides (beryllium oxide, cerium oxide, alumina, soda alumina, magnesium oxide, zinc oxide, titanium oxide, etc.), boron nitride, and magnesium metasilicate (steatite).

The F powder containing a resin or an inorganic substance different from the F polymer has a core-shell structure having the F polymer as a core and the resin or the inorganic substance in the shell, or a core-shell structure having the resin or the inorganic substance as the core and the F polymer in the shell. It is preferable to have. Such F powder is obtained by, for example, coalescing (collision, agglomeration, etc.) of the powder of the F polymer and the powder of the resin or the inorganic substance.

The D50 of the F powder is preferably 10 μm or less, more preferably 6 μm or less, and even more preferably 4 μm or less. The D50 of the F powder is preferably 0.01 μm or more, more preferably 0.1 μm or more, and even more preferably 1 μm or more. The D90 of the F powder is preferably 20 μm or less, more preferably 10 μm or less. When D50 and D90 of the F powder are within such a range, the affinity with the anisotropic filler is further improved, and the dispersion stability of the present dispersion and the physical properties of the molded product are more likely to be improved.

The content of F powder in this dispersion is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 25% by mass or more. The content of the F powder is preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 30% by mass or less. When the content of the F powder is within such a range, the densely contained F powder enhances the affinity between the F powder and the anisotropic filler, and the dispersion stability of the present dispersion is more likely to be improved. In addition, the physical characteristics of the F polymer in the molded product are likely to be remarkably expressed.

The F polymer in this dispersion is a polymer containing a unit (TFE unit) based on tetrafluoroethylene (TFE). The F polymer may contain both PAVE units and HFP units, or may contain only one of them.
As the PAVE, CF ₂ = CFOCF ₃ , CF ₂ = CFOCF ₂ CF ₃ or CF ₂ = CFOCF ₂ CF ₂ CF ₃ (PPVE) is preferable, and PPVE is more preferable.
The melting temperature of the F polymer is preferably 280 to 325 ° C, more preferably 285 to 320 ° C.
The glass transition point of the F polymer is preferably 75 to 125 ° C, more preferably 80 to 100 ° C.

The F polymer may have a polar functional group (oxygen-containing polar group). The polar functional group may be contained in a unit in the F polymer, or may be contained in the terminal group of the main chain of the polymer. Examples of the latter aspect include an F polymer having a polar functional group as a terminal group derived from a polymerization initiator, a chain transfer agent, etc., and an F polymer having a polar functional group obtained by plasma-treating or ionizing the F polymer. Be done.
The polar functional group is preferably a hydroxyl group-containing group or a carbonyl group-containing group, and more preferably a carbonyl group-containing group from the viewpoint of dispersion stability of the dispersion.
The hydroxyl group-containing group is preferably an alcoholic hydroxyl group-containing group, more preferably -CF ₂ CH ₂ OH or -C (CF ₃ ) ₂ OH.
The carbonyl group-containing group is a group containing a carbonyl group (> C (O)), and is a carboxyl group, an alkoxycarbonyl group, an amide group, an isocyanate group, a carbamate group (-OC (O) NH ₂ ), and an acid anhydride residue. A group (-C (O) OC (O)-), an imide residue (-C (O) NHC (O)-etc.) or a carbonate group (-OC (O) O-) is preferred.
The number of carbonyl group-containing groups in the F polymer is preferably 10 to 5000, more preferably 100 to 3000, and even more preferably 800 to 1500, per ^{1 × 10 6 carbon atoms in the main chain.} The number of carbonyl group-containing groups in the F polymer can be quantified by the composition of the polymer or the method described in International Publication No. 2020/145133.

As the F polymer, a tetrafluoroethylene-based polymer containing PAVE units and containing 1.5 to 5.0 mol% of PAVE units with respect to all units is preferable, and includes PAVE units and units based on a monomer having a polar functional group. , A polymer having a polar functional group (1), or a polymer having no polar functional group (2) containing PAVE units and containing 2.0 to 5.0 mol% of PAVE units with respect to all units is more preferable. ..
Not only is the powder excellent in dispersion stability, these F polymers are more likely to be more densely and uniformly distributed in a molded product (polymer layer or the like) formed from the present dispersion. Further, microspherulites are likely to be formed in the molded product, and the adhesion with other components is likely to be enhanced. As a result, it is easier to obtain a molded product having a high degree of physical properties of each of the three components.

The polymer (1) has 90 to 98 mol% of TFE units, 1.5 to 9.97 mol% of PAVE units, and 0.01 to 3 mol of units based on a monomer having a polar functional group, based on all the units. %, It is preferable to contain each.
Further, as the monomer having a polar functional group, itaconic anhydride, citraconic anhydride or 5-norbornene-2,3-dicarboxylic acid anhydride (also known as hymic anhydride; 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) is composed 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.
The fact that the polymer (2) does not have polar functional groups means that the number of polar functional groups contained in the polymer is less than 500 with respect to ^{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 the terminal group of the polymer chain, and is an F polymer having a polar functional group (derived from the polymerization initiator). An F polymer or the like having a polar functional group at the terminal group of the main chain of the polymer) may be fluorinated to produce the polymer. Examples of the fluorination treatment method include a method using fluorine gas (see JP-A-2019-194314, etc.).

The Mohs hardness of the anisotropic filler in the present invention is 4 or less, preferably 3 or less. The Mohs hardness of the anisotropic filler is preferably 1 or more, and more preferably 2 or more. Even if the anisotropic filler is brittle and has a Mohs hardness, the dispersion is excellent in dispersion stability due to the affinity between the anisotropic filler and the F powder, and the physical characteristics of the filler in the molded product are likely to be enhanced.
One type of anisotropic filler may be used, or two or more types having different average particle diameters or types may be used.

The shape of the anisotropic filler in the present invention may be granular, needle-like (fibrous), or plate-like. Specific shapes of the anisotropic filler include spherical, scaly, layered, leafy, apricot kernel, columnar, chicken crown, equiaxed, leafy, mica, block, flat, wedge, and rosette. , Reticulated, prismatic.
The shape of the anisotropic filler is preferably scaly or plate-shaped. If a scaly or plate-shaped anisotropic filler is used, it not only easily forms a card house structure and improves the liquid characteristics (viscosity, dispersion stability, etc.) of the dispersion liquid, but also in the molded product. It is easy to improve the orientation of the filler, and it is easy to improve its function (mechanical strength, thermal conductivity, electrical characteristics, etc.).

Examples of the anisotropic filler include carbon filler, nitride filler, mica filler, clay filler, and talc filler. Boron nitride or talc-containing filler is preferable, and boron nitride-containing filler is more preferable. The crystal form of boron nitride may be any of hexagonal crystal, rhombohedral crystal, cubic crystal, and wurtzite. The present dispersion containing such an anisotropic filler is excellent in dispersion stability and handleability. Further, the electrical interference that the filler gives to the F polymer in the molded product tends to increase, and as a result, the electrical characteristics (particularly, dielectric loss tangent property) of the molded product tend to be improved. Further, the thermal conductivity of the molded product tends to be good.

The content of boron nitride in the filler containing boron nitride is preferably 95% by mass or more, more preferably 99% by mass or more, still more preferably 99.5% by mass or more. The upper limit of the content is 100% by mass. In this case, the molded product tends to be excellent in low line expandability and electrical characteristics.
When the anisotropic filler is added to water, the pH of the water may be acidic, neutral or alkaline, and is preferably alkaline.
The specific surface area of the anisotropic filler is preferably ^{1 ~ 20m 2 / g, 3} ~ 8m 2 / g is more preferable. In this case, the anisotropic filler is likely to get wet in the present dispersion, and the affinity with the F powder is likely to be enhanced. Further, in the molded product, the anisotropic filler and the F polymer are more uniformly dispersed (distributed), and the physical properties of both are easily expressed in a well-balanced manner.

The surface of the anisotropic filler may be surface-treated.
Surface treatment agents include polyhydric alcohols (trimethylolethane, pentaeristol, propylene glycol, etc.), saturated fatty acids (stearic acid, lauric acid, etc.), their esters, alkanolamines, amines (trimethylamine, triethylamine, etc.), paraffin wax. , Silane coupling agents, silicones, polysiloxanes, inorganic substances (oxides such as aluminum, silicon, zirconium, tin, titanium, antimony, oxides, hydroxides, hydrated oxides or phosphates).
As the surface treatment agent, a silane coupling agent is preferable. In such a case, the anisotropic filler and the F polymer powder are more compatible with each other, and the dispersion stability of the present dispersion is likely to be improved. The silane coupling agent preferably has an amino group, a thiol group, a vinyl group, an acroyloxy group or a methacryloyloxy group.

The anisotropic filler may be an anisotropic filler having a hydrophobic portion and a hydrophilic portion. Examples of such an anisotropic filler include an anisotropic filler having a hydrophobic layer on the surface and a hydrophilic layer inside. Specific examples thereof include a plate-shaped multilayer filler having a hydrophobic layer, a hydrophilic layer (moisture-containing layer), and a hydrophobic layer in this order. The water content of the hydrophilic layer is preferably 0.3% by mass or more. In this case, not only the dispersed state of the anisotropic filler in the dispersion is easy to stabilize, but also the orientation of the anisotropic filler when molding the molded product from the dispersion is further enhanced, and the physical properties and anisotropy of the F polymer are further enhanced. It is easy to obtain a molded product that has a high degree of physical properties of the filler.

The anisotropic filler D50 is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 5 μm or more. The D50 of the anisotropic filler is preferably 25 μm or less, more preferably 20 μm or less. The anisotropic filler D90 is preferably 10 μm or more, more preferably 15 μm or more. The D90 of the anisotropic filler is preferably 30 μm or less, more preferably 20 μm or less. When the anisotropic fillers D50 and D90 are in such a range, the affinity with the F powder is further improved, and the dispersion stability of the present dispersion and the physical properties of the molded product are more likely to be improved. Specific examples of such anisotropic fillers include scaly boron nitride fillers and plate-shaped talc fillers.

The aspect ratio of the anisotropic filler is preferably 2 or more, more preferably 3 or more, further preferably 5 or more, and particularly preferably 10 or more. The aspect ratio of the anisotropic filler is preferably 10,000 or less. In this case, it is easy to improve the orientation of the filler in the molded product, and it is easy to enhance its function. Specifically, not only the dispersed state of the anisotropic filler in the dispersion is easy to stabilize, but also the orientation of the anisotropic filler when molding the molded product from the dispersion is further enhanced, which is different from the physical properties of the F polymer. It is easy to obtain a molded product that has the physical characteristics of an anisotropic filler.

The aspect ratio of the anisotropic filler is a value obtained by dividing the average particle size (D50) of the anisotropic filler by the average minor axis (average value of the length in the lateral direction) of the anisotropic filler. is there.
Specific embodiments of the anisotropic filler include fillers having an average minor axis of 1 μm or less or an average major axis (average value of lengths in the longitudinal direction) of 1 μm or more. Specific examples of such an anisotropic filler include a flat plate-shaped talc filler.
The anisotropic filler may have a single-layer structure or a multi-layer structure. Examples of such an anisotropic filler include a talc filler having a three-layer structure.

Suitable specific examples of anisotropic fillers include boron nitride fillers (Showa Denko's "UHP" series, Denka's "HGP" series, "GP" series, etc.) and talc fillers (Nippon Talc's "UHP" series, etc.). SG "series, etc.).

In this dispersion, the D50 of the F powder is smaller than the D50 of the anisotropic filler. That is, in the present dispersion liquid, the affinity between the F powder and the anisotropic filler is enhanced by densely containing the finely granular F powder, and the dispersion stability of the present dispersion liquid is improved. Further, in the molded product, the anisotropic filler is more uniformly dispersed, and its physical properties are likely to be remarkably exhibited.
Specifically, it is preferable that the D50 of the F powder is 0.1 μm or more and less than 5 μm, and the D50 of the anisotropic filler is 1 μm or more and 25 μm or less.

A preferred embodiment of the filler contained in the dispersion liquid is an inorganic filler containing an anisotropic filler (hereinafter, also referred to as “anisotropic filler 1”) and having an average particle size smaller than that of the anisotropic filler 1. (Hereinafter, also referred to as “different filler”). In this case, the improvement of the dispersion stability of the present dispersion due to the interaction between the fillers and the ability to form a dense molded product with different fillers are balanced, and various physical properties (water resistance, water resistance, etc.) of the obtained molded product are obtained. Low line expandability, electrical characteristics, etc.) are more likely to be improved. The different fillers may be inorganic fillers having an average particle size smaller than the anisotropic filler 1, and the material thereof may be the same as or different from that of the anisotropic filler 1.

In this preferred embodiment, it is preferable that the average particle size of the anisotropic filler 1 is more than 6 μm and 15 μm or less, and the average particle size of different fillers is 1 μm or more and 6 μm or less. At this time, it is preferable that the anisotropic filler 1 is a filler containing boron nitride, and the different filler is a filler containing boron nitride or a magnesium metasilicate filler (steatite filler). The aspect ratio of the anisotropic filler 1 is 10 or more, and the aspect ratio of the different fillers is preferably 40 or less, and more preferably less than 10.
In this case, in the obtained molded product, the random orientation of the anisotropic filler 1 is promoted by different fillers, and the physical characteristics of the filler and the physical characteristics of the molded product (adhesiveness, rigidity, etc.) are easily balanced.

In this preferred embodiment, it is also preferable that the average particle size of the anisotropic filler 1 is more than 1 μm and 15 μm or less, and the average particle size of different fillers is 0.01 μm or more and less than 1 μm. At this time, it is preferable that the anisotropic filler 1 is a filler containing boron nitride, and the different filler is a filler containing silicon oxide.
The filler containing silicon oxide is preferably a silica filler or a magnesium metasilicate filler (steatite filler). Further, it is preferable that the surface of the filler containing silicon oxide is surface-treated with a silane coupling agent.

The filler containing silicon oxide is preferably substantially spherical. In this case, it is easy to form a dense molded product. The substantially spherical shape means that the ratio of spherical particles having a ratio of the minor axis to the major axis of 0.7 or more is 95% or more when observed with a scanning electron microscope (SEM). ..
Specific examples of the filler containing silicon oxide include substantially spherical silica filler (“Admafine” series manufactured by Admatex Co., Ltd.), spherical fused silica (“SFP” series manufactured by Denka Co., Ltd., etc.), and hollow silica filler. ("E-SPHERES" series manufactured by Pacific Cement, "Silicas" series manufactured by Nittetsu Mining Co., Ltd., "Ecocosfire" series manufactured by Emerson & Cumming, etc.), Steatite filler ("BST" manufactured by Japan Talc Co., Ltd.) "Series, etc.).

In this preferred embodiment, the different fillers promote the random orientation of the anisotropic filler 1 in the molded product, and the physical properties of the filler in the molded product and the physical characteristics of the molded product (adhesiveness, surface smoothness, rigidity, etc.) are balanced. It's easy to do. That is, the orientation of the anisotropic filler 1 is partially disturbed in the molded product, and the electrical characteristics due to the high filler orientation and the rigidity, adhesiveness and surface smoothness due to the low linear expansion and the disorder of the filler orientation are caused. The property is highly likely to be provided in the molded product.

Further, the filler in this preferred embodiment may be contained in a state having a multimodal particle size distribution. In this case, from the viewpoint of easily forming a dense molded product, it is preferable that the peak caused by the present filler 1 is the highest among the peaks in the particle size distribution. Specifically, the filler is preferably contained in a state having a bimodal particle size distribution having peaks in a region of 6 μm or less and a region of more than 6 μm, respectively.

Further, the filler in this preferred embodiment may contain at least a part thereof attached to the surface of the F powder, or may contain at least a part of the F powder attached to the surface thereof. In this case, it can be said that the present dispersion liquid contains a composite body of F powder and the anisotropic filler 1, and its dispersion stability is further improved, and various physical properties (water resistance, low line) of the molded product formed from the composite body are further improved. Expandability, electrical characteristics, etc.) are more likely to be improved.

Further, in this preferred embodiment, the mass ratio of the contents of the different fillers to the content of the anisotropic filler 1 is preferably 0.1 or more, more preferably 0.2 or more. The mass ratio is preferably 2 or less, and more preferably 1 or less. In this case, the dispersion stability of the dispersion liquid and the physical properties of the molded product are easily balanced.

The content of the anisotropic filler in this dispersion is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 25% by mass or more. The content of the F powder is preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 30% by mass or less.
The content of the F polymer and the content of the anisotropic filler in this dispersion are preferably 5% by mass or more, respectively. The sum of the contents of both is preferably 60% by mass or less. Even if each of the F polymer and the anisotropic filler is contained in such a high ratio (content), this dispersion has excellent dispersion stability and has a high degree of physical characteristics of both, as described above by the mechanism of action. It is easy to form a molded product.

From the viewpoint of improving dispersion stability and handleability, the dispersion liquid preferably further contains a surfactant.
The surfactant is preferably nonionic.
The hydrophilic moiety of the surfactant preferably has an oxyalkylene group or an alcoholic hydroxyl group.
The oxyalkylene group may be composed of one kind or two or more kinds. In the latter case, different types of oxyalkylene groups may be arranged in a random manner or in a block shape.
The oxyalkylene group is preferably an oxyethylene group.

The hydrophobic moiety of the surfactant preferably has an acetylene group, a polysiloxane group, a perfluoroalkyl group or a perfluoroalkenyl group. In other words, the surfactant is preferably an acetylene-based surfactant, a silicone-based surfactant or a fluorine-based surfactant, and more preferably a silicone-based surfactant.
As the fluorine-based surfactant, a fluorine-based surfactant having a hydroxyl group (particularly an alcoholic hydroxyl group) or an oxyalkylene group and a perfluoroalkyl group or a perfluoroalkenyl group is more preferable.
Specific examples of surfactants include "Futergent" series (manufactured by Neos), "Surflon" series (manufactured by AGC Seimi Chemical Co., Ltd.), "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 shares) (Manufactured by a company), "KF-6011", "KF-6043" (manufactured by Shin-Etsu Chemical Co., Ltd.).
The content of the surfactant in this dispersion is preferably 1 to 15% by mass. In this case, the affinity between the components is enhanced, and the dispersion stability of the present dispersion is likely to be further improved.

The liquid dispersion medium in the present invention is a liquid compound that is inert at 25 ° C. and functions as a dispersion medium for F powder and anisotropic filler. The liquid dispersion medium may be water or a non-aqueous dispersion medium. The liquid dispersion medium may be one kind or two or more kinds. In this case, dissimilar liquid compounds are preferably compatible.
The boiling point of the liquid dispersion medium is preferably 125 to 250 ° C. In this case, when the molded product is formed from the present dispersion, the anisotropic filler is likely to be oriented and the physical properties of the molded product are likely to be improved.
As the liquid dispersion medium, one or more liquid compounds selected from the group consisting of amides, ketones and esters are preferable from the viewpoint of dispersion stability of the dispersion, and N-methyl-2-pyrrolidone, γ-butyrolactone and cyclohexanone are preferable. Alternatively, cyclopentanone is more preferable.
The content of the liquid dispersion medium in this dispersion is preferably 50% by mass or more, more preferably 60% by mass or more. The content of the liquid dispersion medium is preferably 90% by mass or less, more preferably 80% by mass or less.

The viscosity of this dispersion is preferably 50 mPa · s or more, more preferably 100 mPa · s or more. The viscosity of this dispersion is preferably 10,000 mPa · s or less, more preferably 1000 mPa · s or less, and even more preferably 800 mPa · s or less.
The thixotropy ratio of this dispersion is preferably 1.0 or more. The thixotropy of the dispersion is preferably 3.0 or less, more preferably 2.0 or less.
The component dispersion layer ratio of the dispersion liquid is preferably 60% or more, more preferably 70% or more, and further preferably 80% or more. Here, the component dispersion layer ratio is the main dispersion in the screw tube before and after the main dispersion liquid (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 of the liquid and the height of the component dispersion layer.
Component dispersion layer ratio (%) = (height of component dispersion layer) / (overall height of this dispersion) × 100
If the component dispersion layer is not confirmed after standing and the state does not change, the component dispersion layer ratio is set to 100%, assuming that the overall height of the dispersion liquid does not change.
This dispersion is easy to adjust to the viscosity, thixotropic property or component dispersion layer ratio within such a range by the above-mentioned mechanism of action, and is excellent in handleability.

The dispersion may further contain another resin (polymer) different from the F polymer. The other resin may be a thermosetting resin or a thermoplastic resin.
Examples of other resins include epoxy resins, maleimide resins, urethane resins, elastomers, polyimides, polyamic acids, polyamideimides, polyphenylene ethers, polyphenylene oxides, liquid crystal polyesters, and fluoropolymers other than F polymers.
A preferred embodiment of the other resin is an aromatic polymer varnish. As the aromatic polymer, aromatic polyimide or aromatic polyamic acid is preferable, and thermoplastic aromatic polyimide is more preferable. In this case, the physical characteristics of the F polymer and the anisotropic filler are likely to be remarkably exhibited in the molded product. Further, when the molded product is formed from the present dispersion liquid, the powder falling of the F powder is suppressed, and the adhesiveness thereof is likely to be improved.

The content of the aromatic polymer in this dispersion is preferably 1 to 30% by mass, more preferably 5 to 25% by mass. The ratio of the content of the aromatic polymer to the content of the F polymer by mass is preferably 1.0 or less, more preferably 0.1 to 0.7.
Preferable embodiments of other resins include powders of polytetrafluoroethylene (PTFE). In this case, the physical characteristics based on PTFE (electrical characteristics such as low dielectric loss tangent property) are likely to be remarkably exhibited in the molded product. Further, PTFE serves as a nucleating agent, and the F polymer in the molded product tends to form microcrystals, the adhesion on the surface of the molded product is improved, and the adhesiveness thereof is likely to be enhanced. In addition, the orientation of the filler in the molded product is likely to be improved, and its function is likely to be enhanced.

As the PTFE, PTFE (low molecular weight PTFE) having a number average molecular weight (Mn) of 200,000 or less calculated based on the following formula (1) is preferable.
Mn = 2.1 × 10 ¹⁰ × ΔHc- ^5.16 ... (1)
In the formula (1), ΔHc indicates the calorie crystallization (cal / g) of PTFE measured by the differential scanning calorimetry.
The Mn of low molecular weight PTFE is preferably 100,000 or less, more preferably 50,000 or less. The Mn of low molecular weight PTFE is preferably 10,000 or more.

The content of PTFE in this dispersion is preferably 1 to 30% by mass, more preferably 5 to 20% by mass. The ratio of the content of PTFE to the content of F polymer by mass is preferably 1.0 or less, more preferably 0.1 to 0.4.
When the present dispersion liquid contains another resin, the present dispersion liquid may be produced by mixing the present dispersion liquid and the powder of the other resin, or the present dispersion liquid and the varnish containing the other resin are mixed and produced. You may.

In addition to the above-mentioned components, this dispersion contains a texo-imparting agent, a defoaming agent, a silane coupling agent, a dehydrating agent, a plasticizer, a weathering agent, an antioxidant, a heat stabilizer, a lubricant, an antistatic agent, and an increase. It may contain additives such as whitening agents, colorants, conductive agents, mold release agents, surface treatment agents, viscosity modifiers, flame retardants, and isotropic fillers.

This dispersion can be produced by mixing F powder, an anisotropic filler, and a liquid dispersion medium. A liquid composition containing F powder and a liquid composition containing an anisotropic filler are prepared, and both are prepared. It is preferably produced by mixing.
Specific examples of the production method of the dispersion liquid include a production method in which the F powder, the anisotropic filler 1, a different filler, and a liquid dispersion medium are mixed. In this mixing, the F powder and the liquid dispersion medium may be mixed in advance to form a liquid composition, or the anisotropic filler 1 and the above-mentioned different filler may be mixed in advance.

Examples of the mixer used for mixing include a mixer with a stirring blade, a Henschel mixer, a ribbon blender, a swing type mixer, a vibration type mixer, a rotary type mixer, and the like, and specifically, a homodisper, a homogenizer, and a ball mill. Can be mentioned.
The mixing method may be either a batch method or a continuous method. The mixer used for batch mixing is preferably a Henschel mixer, a pressurized kneader, a Banbury mixer or a planetary mixer.

The mixing is preferably performed by stirring, and more preferably by rotary stirring with a stirring blade.
The stirring speed is preferably 800 rpm or more, more preferably 2000 rpm or more. The stirring speed is preferably 10000 rpm or less, more preferably 8000 rpm or less. In this case, the F powder and the anisotropic filler are sheared and the agglomerates are easily crushed, so that the present dispersion having excellent dispersibility can be easily obtained.
Furthermore, if the anisotropic filler is scaly or plate-shaped, the layered aggregates (secondary particles) of the anisotropic filler that are usually formed are efficiently crushed to form a cardhouse structure. , This dispersion having excellent dispersibility is easily formed.

The molded product of the present invention (hereinafter, also referred to as “this molded product”) differs from a tetrafluoroethylene-based polymer containing PAVE units (hereinafter, also referred to as “PFA-based polymer”) in that it has a Mohs hardness of 4 or less. Includes with directional filler. The PFA-based polymer is a polymer having a polar functional group, or a polymer containing 2.0 to 5.0 mol% of PAVE units with respect to all units and having no polar functional group. The proportion (content) of the anisotropic filler occupying is 10% by mass or more.
Examples of the shape of the molded product include a layered shape, a plate shape, and a lump shape, and a layered shape is preferable. The thickness of the layered molded product is preferably 150 μm or less. Such a layered molded product is useful for producing impregnated products such as films and prepregs and laminated plates.

The definition and scope of the anisotropic filler in the molded product are the same as those of the anisotropic filler in the dispersion, including preferred embodiments.
The type and range of polar functional groups of the PFA-based polymer in this molded product are the same as those of the F polymer, including preferred embodiments. The PFA-based polymer is preferably polymer (1) or polymer (2).

The content of the anisotropic filler in the molded product is preferably 15% by mass or more, more preferably 25% by mass or more. The content of the anisotropic filler is preferably 50% by mass or less, more preferably 40% by mass or less.
The content of the PFA polymer in the molded product is preferably 40% by mass or more, more preferably 50% by mass or more, still more preferably 60% by mass or more. The content of the PFA polymer is preferably 95% by mass or less, more preferably 80% by mass or less, and further preferably 70% by mass or less. When the content of the PFA-based polymer is within such a range, the physical properties of the PFA-based polymer are likely to be remarkably exhibited in this molded product. In addition, powder dropping of the anisotropic filler from the molded product is suppressed.

The molded product preferably further contains an aromatic polymer (particularly aromatic polyimide) or PTFE. The respective definitions and ranges of the aromatic polymer and PTFE in the molded product and the ratio of each content to the content of the F polymer by mass are the same as those in the present dispersion.
The molded product is preferably formed from the dispersion liquid. Specifically, if the present dispersion is applied to the surface of the base material and the liquid dispersion medium is removed, the molded product contains a layer containing a PFA polymer and an anisotropic filler (hereinafter, "main layer"). Also referred to as) can be easily formed on the surface of the base material. More specifically, if the present dispersion is applied to the surface of the substrate, the substrate is heated to remove the liquid dispersion medium, and the PFA-based polymer is melt-fired by further heating, the substrate and the surface of the substrate are subjected to. A laminate having the formed main layer is obtained. The temperature in the former heating is preferably 120 ° C. to 200 ° C. On the other hand, the temperature in the latter heating is preferably 250 ° C. to 400 ° C., more preferably 300 to 380 ° C.

The substrate includes a metal substrate (copper, nickel, aluminum, titanium, metal foil such as an alloy thereof, etc.), a resin film (polyethylene, polyarylate, polysulfone, polyallylsulfone, polyamide, polyesteramide, polyphenylene sulfide, polyallyl). Examples thereof include ether ketones, polyamideimides, films such as liquid crystal polyesters and liquid crystal polyesteramides), and prepregs (precursors of fiber-reinforced resin substrates).
It is preferable that the dispersion liquid is applied by coating. The coating methods include spray method, roll coating method, spin coating method, gravure coating method, micro gravure coating method, gravure offset method, knife coating method, kiss coating method, bar coating method, die coating method, fountain Mayer bar method, and slot die coating. The law can be mentioned.
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 thickness of this layer is preferably 0.1 to 150 μm. Specifically, if the substrate is a metal foil, the thickness of this layer is preferably 1 to 30 μm. When the substrate is a resin film, the thickness of this layer is preferably 1 to 150 μm, more preferably 10 to 50 μm.
The present dispersion may be applied only to one surface of the substrate, or may be applied to both sides of the substrate. In the former, a substrate and a laminate having the main layer on one surface of the substrate are obtained, and in the latter, a laminate having the main layer on both the surface of the substrate and the substrate is obtained. Since the latter laminate 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 a main layer on at least one surface of the metal foil, a polyimide film, and a multilayer film having a main layer on both surfaces of the polyimide film. Can be mentioned.
These laminates are excellent in various physical properties such as electrical characteristics, and are suitable as a printed circuit board material or the like. Specifically, such a laminate can be used for manufacturing a flexible printed circuit board or a rigid printed circuit board.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.
1. 1. Preparation of each ingredient [Powder]
Powder 1: Contains 97.9 mol%, 0.1 mol%, and 2.0 mol% of TFE units, NAH units, and PPVE units in this order, and contains 1000 ^{carbonyl groups per 1 × 10 6 carbon atoms in the main chain.} Powder (D50: 2.1 μm) made of PFA-based polymer 1 (melting temperature: 300 ° C.)
Powder 2: PFA-based polymer 2 containing 97.5 mol% and 2.5 mol% of TFE units and PPVE units in this order and having ^{40 carbonyl groups per 1 × 10 6} carbon atoms in the main chain (melting temperature 305). ℃) powder (D50: 1.8 μm)
Powder 3: Powder composed of PFA polymer 2 (D50: 5.3 μm)
Powder 4: Powder consisting of PTFE with a number average molecular weight of 20,000 (D50: 3.2 μm)

[Anisotropy filler]
Filler 1: A scaly filler made of boron nitride (D50: 7.0 μm)
Filler 2: A scaly filler made of boron nitride (D50: 3.7 μm)
Filler 3: A scaly filler made of boron nitride (D50: 7.3 μm)
Filler 4: A plate-shaped talc filler having a three-layer structure having a hydrophobic layer, a hydrophilic layer, and a hydrophobic layer in this order (D50: 4.5 μm, average major axis: 5.1 μm, average minor axis: 0.2 μm, aspect ratio: 25, "SG-95" manufactured by Japan Talc)
The Mohs hardness of the fillers 1 to 3 is 2, and the Mohs hardness of the filler 4 is 1. Fillers 1, 2 and 4 are surface-treated with a silane coupling agent.
[Liquid dispersion medium]
NMP: N-methyl-2-pyrrolidone

[Surfactant]
Surfactant 1: CH ₂ = C (CH ₃ ) C (O) OCH ₂ CH ₂ (CF ₂ ) ₆ F and CH ₂ = C (CH ₃ ) C (O) (OCH ₂ CH ₂ ) ₂₃ OH Nonionic polymer that is a copolymer and has a fluorine content of 35% by mass [Aromatic polymer varnish]
Varnish 1: Varnish in which thermoplastic aromatic polyimide (PI1) is dissolved in NMP (solid content concentration: 18% by mass)

2. Production example of dispersion liquid (Example 1)
First, powder 1, varnish 1, surfactant 1 and NMP were put into the pot, and zirconia balls were put into the pot. Then, the pot was rolled at 150 rpm for 1 hour to prepare a composition. In another pot, filler 1, surfactant 1 and NMP were charged, and zirconia balls were charged. Then, the pot was rolled at 150 rpm for 1 hour to prepare a composition.
In still another pot, both compositions were charged and zirconia balls were charged. Then, the pot was rolled at 150 rpm for 1 hour, powder 1 (11 parts by mass), filler 1 (11 parts by mass), PI1 (7 parts by mass), surfactant 1 (4 parts by mass) and NMP (67 parts by mass). ) Was obtained as a dispersion 1 (viscosity: 400 mPa · s).
(Examples 2-9)
Dispersions 2 to 9 were obtained in the same manner as in Example 1 except that the types and amounts of the powder, filler, varnish, surfactant and liquid dispersion medium were changed as shown in Table 1 below.
(Example 10)
A dispersion liquid 10 was obtained in the same manner as in Example 1 except that 3 parts by mass of filler 1 and 8 parts by mass of filler 2 were used instead of 11 parts by mass of filler 1.

3. 3. Production Example of Molded Product 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 metal foil on which the wet film was formed was passed through a drying furnace at 120 ° 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 metal foil and a polymer layer (thickness 5 μm) as a molded product containing a melt-fired product of powder 1 and a filler 1 on the surface thereof was produced.
Laminates 2 to 10 were produced in the same manner as the laminate 1 except that the dispersion 1 was changed to each of the dispersions 2 to 10.

4. Evaluation 4-1. Dispersion Stability of Dispersion Liquid After storing the dispersion liquids 1 to 10 in a container at 25 ° C., the dispersibility was visually confirmed, and the dispersion stability was evaluated according to the following criteria.
[Evaluation criteria]
⊚: The agglomerate is not visible.
〇: Fine agglomerates are visually recognized on the side wall of the container. When lightly stirred, it was uniformly redispersed.
Δ: Agglomerates are also visible at the bottom of the container. When agitated with shearing, it redisperses uniformly.
X: It is visually recognized that the agglomerates are also precipitated at the bottom of the container. Redispersion is difficult even with shearing and stirring.

4-2. Physical characteristics of the laminate 4-2-1. Surface smoothness The surface smoothness of the polymer layers of the laminated bodies 1 to 9 was visually confirmed, and the surface smoothness was evaluated according to the following criteria.
[Evaluation criteria]
〇: The entire surface of the polymer layer is smooth.
Δ: Unevenness due to lack of polymer or filler is visible at the edge of the surface of the polymer layer.
X: Unevenness due to lack of polymer or inorganic filler is visible on the entire surface of the polymer layer.

4-2-2. Linear expansion coefficient For each of the laminated bodies 1 to 4, 9 and 10, a 180 mm square test piece was cut out and tested in the range of 25 ° C. or higher and 260 ° C. or lower according to the measurement method specified in JIS C 6471: 1995. The coefficient of linear expansion of one piece was measured.
[Evaluation criteria]
〇: 30 ppm / ° C or less.
X: Over 30 ppm / ° C.

4-2-3. For each of the dielectric loss tangent laminates 1 to 4, 9 and 10, the copper foil of the laminate was removed by etching with an aqueous ferric chloride solution to prepare a single polymer layer, which was then subjected to the SPDR (split post dielectric resonance) method. Then, the dielectric loss tangent (measurement frequency: 10 GHz) of the polymer layer was measured.
[Evaluation criteria]
〇: The dielectric loss tangent is less than 0.0010.
Δ: The dielectric loss tangent is 0.0010 or more and 0.0025 or less.
X: The dielectric loss tangent is more than 0.0025.
The evaluation results are summarized in Table 2 below.

5. Production example of dispersion liquid (Part 2)
(Example 11)
First, powder 1, surfactant 1 and NMP were added to and mixed in a pot, and the mixture was stirred with a homodisper at 2000 rpm for 1 hour to prepare a composition. Filler 1, surfactant 1 and NMP were put into another pot and stirred with a homodisper at 2000 rpm for 1 hour to prepare a composition. The compositions of both were put into yet another pot, and stirred at 2000 rpm for 1 hour with a homodispar, powder 1 (11 parts by mass), filler 1 (11 parts by mass), and surfactant 1 (4 parts by mass). ) And NMP (74 parts by mass), a dispersion liquid 11 (viscosity: 300 mPa · s, component dispersion layer ratio: 80%) was obtained.
(Example 12)
A dispersion liquid 12 was obtained in the same manner as in Example 11 except that an ultrasonic homogenizer without stirring by a stirring blade was used instead of the homodisper (viscosity: 300 mPa · s, component dispersion layer ratio: 50%). ..

6. Manufacturing example of laminated body (2)
A liquid film was formed by applying the dispersion liquid 11 on the surface of an aluminum foil having a thickness of 18 μm by a roll-to-roll method by a gravure reverse method. Next, the aluminum foil on which the liquid film was formed was passed through a drying oven at 120 ° C. for 5 minutes and dried by heating. Then, the dry film was heated at 340 ° C. for 3 minutes in a far-infrared oven under a nitrogen atmosphere. As a result, the laminate 11 in which the polymer layer (thickness: 10 μm) was formed on the surface of the aluminum foil was manufactured. Further, the laminated body 12 was manufactured in the same manner as the laminated body 11 except that the dispersion liquid 12 was used instead of the dispersion liquid 11.
As a result of observing the cross section of each laminated body by SEM, the distribution state of the filler 1 was denser in the polymer layer of the laminated body 11 than in the polymer layer of the laminated body 12. Further, the polymer layer of the laminated body 11 had a lower dielectric loss tangent than the polymer layer of the laminated body 12. The laminated body 11 was superior to the laminated body 12 in thermal conductivity and bendability.

The dispersion liquid of the present invention has excellent dispersion stability, and has physical properties based on an F polymer (PFA-based polymer) and properties based on an anisotropic filler (impregnated products such as films and prepregs, laminated plates, and coatings). Can be used for manufacturing materials, etc.). The molded product of the present invention is useful as an antenna part, a printed substrate, an aircraft part, an automobile part, a sports tool, a food industry product, a paint, a cosmetic, and the like. (Electric wires, etc.), electrical insulating tape, insulating tape 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, belt conveyors) , Food transport belts, etc.), tools (shovels, shavings, cuttings, saws, etc.), boilers, hoppers, pipes, ovens, baking molds, chutes, dies, toilet bowls, container covering materials, heat exchangers (fins, etc.) , Heat transfer tube, etc.) is useful as an outer surface coating material.

Claims

A powder of a tetrafluoroethylene polymer containing a unit based on perfluoro (alkyl vinyl ether) or a unit based on hexafluoropropylene, an anisotropic filler having a Mohs hardness of 4 or less, and a liquid dispersion medium, and the average of the powders is contained. A dispersion having a particle size smaller than the average particle size of the anisotropic filler.
The dispersion liquid according to claim 1, wherein the content of the tetrafluoroethylene polymer and the content of the anisotropic filler are 5% by mass or more, respectively.
The dispersion liquid according to claim 1 or 2, wherein the anisotropic filler has a scale-like or plate-like shape.
The dispersion liquid according to any one of claims 1 to 3, wherein the anisotropic filler has an aspect ratio of 2 or more.
The dispersion liquid according to any one of claims 1 to 4, wherein the anisotropic filler is an anisotropic filler containing boron nitride or talc.
The dispersion liquid according to any one of claims 1 to 5, further comprising a polytetrafluoroethylene powder or an aromatic polymer.
The dispersion liquid according to any one of claims 1 to 6, wherein the component dispersion layer ratio is 60% or more.
The method for producing a dispersion according to any one of claims 1 to 7, wherein the powder, the anisotropic filler, an inorganic filler having an average particle size smaller than that of the anisotropic filler, and a liquid. A method for producing a dispersion liquid in which a dispersion medium is mixed.
The production method according to claim 8, wherein the mixing is performed by stirring.
A molded product containing a tetrafluoroethylene-based polymer containing a unit based on perfluoro (alkyl vinyl ether) and an anisotropic filler having a Mohs hardness of 4 or less.
The tetrafluoroethylene-based polymer contains 2.0 to 5.0 mol% of the polymer having a polar functional group or the unit based on the perfluoro (alkyl vinyl ether) with respect to all the units, and has no polar functional group. A molded product which is a polymer and in which the ratio of the anisotropic filler to the molded product is 10% by mass or more.
The molded product according to claim 10, wherein the anisotropic filler has an aspect ratio of 2 or more.
The molded product according to claim 11, wherein the anisotropic filler is a scaly anisotropic filler containing boron nitride or a plate-shaped anisotropic filler containing talc.
The molded product according to any one of claims 9 to 12, wherein the anisotropic filler has an average particle size of 1 μm or more.
The molded product according to any one of claims 9 to 13, further comprising polytetrafluoroethylene or an aromatic polymer.
The molded product according to any one of claims 9 to 14, wherein the molded product is a layered molded product having a thickness of 150 μm or less.