WO2021187456A1

WO2021187456A1 - Method for producing surface-modified tetrafluoroethylene-based polymer, method for producing modified powder, liquid composition, method for producing modified molded article, and modified molded article

Info

Publication number: WO2021187456A1
Application number: PCT/JP2021/010519
Authority: WO
Inventors: 圭介中尾; 敦美山邊
Original assignee: Ａｇｃ株式会社
Priority date: 2020-03-19
Filing date: 2021-03-16
Publication date: 2021-09-23
Also published as: CN115175953A; JPWO2021187456A1; TW202140649A; KR20220155311A

Abstract

[Problem] To provide: a method for producing a modified tetrafluoroethylene-based polymer and a powder by modifying a tetrafluoroethylene-based polymer and a powder of the polymer; and a method for producing a modified molded article by highly modifying the surface of a molded article of a tetrafluoroethylene-based polymer. [Solution] A method for producing a modified tetrafluoroethylene-based polymer and a powder, the method comprising subjecting a tetrafluoroethylene-based polymer and a powder of the polymer to a plasma treatment under an atmosphere having a pressure close to the atmospheric pressure to produce a surface-modified tetrafluoroethylene-based polymer; and a method for producing a molded article which has, as at least a portion of the surface thereof, a modified layer formed by introducing a hydrogen atom into a tetrafluoroethylene-based polymer, the method comprising subjecting a surface layer of a molded article having, as at least a portion of the surface layer thereof, a surface layer comprising the tetrafluoroethylene-based polymer to a plasma treatment under an atmosphere containing a reducing gas having a hydrogen atom and having a pressure close to the atmospheric pressure.

Description

A method for producing a surface-modified tetrafluoroethylene polymer, a method for producing a modified powder, a liquid composition, a method for producing a modified molded product, and a modified molded product.

The present invention relates to a method for producing a surface-modified tetrafluoroethylene polymer, a method for producing a modified powder, a liquid composition, a method for producing a modified molded product, and a modified molded product.

The tetrafluoroethylene polymer has excellent physical properties such as releasability, electrical insulation, water and oil repellency, chemical resistance, weather resistance, and heat resistance, and the liquid composition in which the powder is dispersed can be molded in various ways. It is useful as a material that can easily form an object (Patent Document 1).
However, the tetrafluoroethylene-based polymer has extremely low polarity and has poor interaction with other compounds such as a liquid dispersion medium, so that the dispersibility of the powder is still insufficient. Therefore, in order to improve the dispersibility of the powder and adjust the liquid physical characteristics of the liquid composition, an adjusting agent such as a surfactant or a thickener is often added to the liquid composition.

Further, the tetrafluoroethylene polymer film has excellent physical properties such as electrical insulation, water and oil repellency, chemical resistance, and heat resistance, and is useful as a printed circuit board material (Patent Document 2). However, the film of the tetrafluoroethylene polymer is not yet sufficiently adhesive. Therefore, it has been studied to modify the surface of the film for the purpose of improving the surface physical properties such as adhesiveness. Patent Document 3 describes a method of introducing a peroxide functional group onto the surface of a film by plasma-treating a polytetrafluoroethylene film in an atmosphere near atmospheric pressure containing a rare gas.

Further, the tetrafluoroethylene polymer is a low-polarity polymer having excellent insulation resistance and dielectric breakdown, and the surface of the molded product is difficult to be easily modified. Further, the behavior when the tetrafluoroethylene polymer is subjected to plasma treatment is not fully known, and the effect may be difficult to stabilize and the effect may not be sustained.

Therefore, the current situation is that other methods are combined in the plasma treatment of tetrafluoroethylene polymer moldings. For example, in Patent Document 3, a polytetrafluoroethylene film is plasma-treated to introduce a peroxide functional group on the surface, further immersed in water to introduce a hydroxyl group on the surface, and a silane coupling agent is further acted on. The film is surface-modified.

International Publication 2016/159102 Pamphlet International Publication No. 2019/142790 Pamphlet Japanese Unexamined Patent Publication No. 2013-049819

The present inventors have investigated a plasma treatment method that highly modifies the surface of a tetrafluoroethylene polymer powder.
As a result, when the surface of the tetrafluoroethylene polymer powder is treated under predetermined plasma treatment conditions, the surface is modified, and the surface physical properties such as the wettability of the powder and the surface physical properties are prepared without impairing the physical properties. We have found that the dispersibility of the liquid composition is improved.

Further, in the plasma treatment of the tetrafluoroethylene-based polymer molded product, the present inventors highly modify the surface of the tetrafluoroethylene-based polymer molded product, which does not require the combination as described in Patent Document 3. The possible plasma processing conditions were examined. As a result, it was found that when such a molded product is treated under predetermined plasma treatment conditions, a stable layer is formed. Further, it has been found that the formation of such a layer improves the wettability of the molded product and improves the surface physical properties such as adhesiveness without impairing the physical properties of the tetrafluoroethylene polymer of the entire molded product.

An object of the present invention is to provide a method for highly modifying a tetrafluoroethylene polymer to improve its physical properties.
An object of the present invention is to provide a method for highly surface-modifying a tetrafluoroethylene polymer powder to improve its surface physical characteristics, and a liquid composition prepared from the method and having excellent liquid physical characteristics such as dispersibility. do.
An object of the present invention is to provide a method for highly surface-modifying a molded product of a tetrafluoroethylene-based polymer to improve the surface physical characteristics thereof, and a molded product of a highly surface-modified tetrafluoroethylene-based polymer. do.

The present invention has the following aspects.
<1> A method for producing a modified tetrafluoroethylene polymer, wherein the tetrafluoroethylene polymer is plasma-treated in an atmosphere near atmospheric pressure to obtain a surface-modified tetrafluoroethylene polymer.
<2> A method for producing a modified powder, in which a tetrafluoroethylene polymer powder is plasma-treated in an atmosphere near atmospheric pressure to modify the surface of the powder.
<3> The powder is plasma-treated in an atmosphere near atmospheric pressure containing a reducing gas having a hydrogen atom to obtain a powder formed by introducing a hydrogen atom into the tetrafluoroethylene polymer. 2> Manufacturing method.
<4> The production method of <2> or <3>, wherein the plasma treatment is performed in an atmosphere in which air is shielded.
<5> The production method of <2> to <4>, wherein the powder is plasma-treated in advance in an atmosphere containing a rare gas before the plasma treatment is performed.
<6> The production method of <2> to <5> above, wherein the atmosphere contains at least one gas of a reducing gas having a hydrogen atom, a vinyl compound and a vinylidene compound.
<7> The production method of <2> to <6>, wherein the atmosphere further contains a rare gas.
<8> The production method of <2> to <7> above, wherein the pressure near the atmospheric pressure is 0.08 to 0.12 MPa.
<9> The production method of <2> to <8> above, wherein the average particle size of the powder is 50 μm or less.
<10> The production method of <2> to <9> above, wherein the tetrafluoroethylene polymer is a tetrafluoroethylene polymer having a fluorine content of 70 to 76% by mass.
<11> The method for producing <2> to <10> above, wherein the tetrafluoroethylene polymer has an atomic group containing an oxygen atom.
<12> A liquid composition containing the modified powder obtained by any of the production methods <2> to <11> and a liquid dispersion medium in which the modified powder is dispersed.
<13> The liquid composition of <12> above, wherein the modified powder has an average particle size of 50 μm or less.
<14> The liquid composition of <12> or <13>, wherein the tetrafluoroethylene-based polymer is a tetrafluoroethylene-based polymer having a fluorine content of 70 to 76% by mass.
<15> The liquid composition of <12> to <14> above, wherein the tetrafluoroethylene polymer has an atomic group containing an oxygen atom.
<16> The tetrafluoroethylene polymer in which the surface layer of a molded product having at least a part of the surface layer containing a tetrafluoroethylene polymer is plasma-treated in an atmosphere near atmospheric pressure containing a reducing gas having a hydrogen atom. A method for producing a molded product having a modified layer formed by introducing a hydrogen atom into at least a part of the surface.
<17> The manufacturing method of <16>, wherein the plasma treatment is performed in an atmosphere in which air is shielded.
<18> The production method according to <16> or <17>, wherein the surface layer is plasma-treated in advance in an atmosphere that does not contain a reducing gas before the plasma treatment is performed.
<19> The production method of <16> to <18> above, wherein the reducing gas is hydrogen gas, ammonia gas, or hydrocarbon gas.
<20> The production method of <16> to <19> above, wherein the atmosphere of the plasma treatment further contains nitrogen gas or a rare gas.
<21> The production method of <16> to <20> above, wherein the pressure near the atmospheric pressure is 0.08 to 0.12 MPa.
<22> The molded product having at least a part of the surface layer containing the tetrafluoroethylene polymer is a film of the tetrafluoroethylene polymer or a laminate having a base material layer and a layer of the tetrafluoroethylene polymer. The manufacturing method of <16> to <21> above.
<23> The method for producing <16> to <22>, wherein the tetrafluoroethylene polymer has a fluorine content of 70 to 76% by mass.
<24> The method for producing <16> to <23> above, wherein the tetrafluoroethylene polymer has an atomic group containing an oxygen atom.
<25> A modified layer formed by introducing hydrogen atoms into a tetrafluoroethylene polymer is provided on at least a part of the surface, and the modified layer has a depth from the surface measured by X-ray photoelectron spectroscopy. The maximum height of the peak at 284 eV to 286 eV in the region up to 1 nm is 0.2 times or more the maximum height of the peak at 289 eV to 295 eV in the region, and the content of fluorine atoms in the region is high. A molded product containing a tetrafluoroethylene-based polymer having a proportion of 55% or less.
<26> The molded product of <25>, wherein the tetrafluoroethylene polymer has a fluorine content of 70 to 76% by mass.
<27> The molded product of <25> or <26>, wherein the tetrafluoroethylene polymer has an atomic group containing an oxygen atom.
<28> The molded product of <25> to <27>, wherein the modified layer has a thickness of less than 1000 nm.
<29>
The molded product of <25> to <27> above, wherein the molded product is a film of a tetrafluoroethylene-based polymer or a laminate having a base material layer and a layer of a tetrafluoroethylene-based polymer.

According to the present invention, a highly modified tetrafluoroethylene polymer can be produced.
According to the present invention, a modified powder of a tetrafluoroethylene-based polymer having excellent wettability and dispersibility can be produced without impairing the physical properties of the tetrafluoroethylene-based polymer, and then a liquid having excellent liquid physical properties can be easily produced. The composition can be produced. From such a liquid composition, a molded product (layered molded product, single film, etc.) having the physical characteristics of a tetrafluoroethylene polymer and having excellent adhesiveness can be easily produced.
According to the present invention, it is possible to produce a molded product of a tetrafluoroethylene polymer having a stable modified layer on at least a part of the surface, which is formed by efficiently introducing hydrogen atoms into the tetrafluoroethylene polymer. Further, a tetrafluoroethylene-based polymer molded product having the physical properties of the tetrafluoroethylene-based polymer as a whole and having improved surface physical properties such as adhesiveness can be obtained.

The following terms have the following meanings.
The "tetrafluoroethylene-based polymer" is a polymer containing a unit (hereinafter, also referred to as "TFE unit") based on tetrafluoroethylene (hereinafter, also referred to as "TFE").
The "glass transition point (Tg) of a polymer" is a value measured by analyzing a polymer by a dynamic viscoelasticity measurement (DMA) method.
The “polymer melting temperature (melting point)” is the temperature corresponding to the maximum value of the melting peak measured by the differential scanning calorimetry (DSC) method.
"(Meta) acrylate" is a general term for acrylate and methacrylate.
“D50” is the average particle size of the powder, which is the volume-based cumulative 50% diameter of the powder obtained by the laser diffraction / scattering method. That is, the particle size distribution of the powder is measured by the laser diffraction / scattering method, the cumulative curve is obtained with the total volume of the powder population as 100%, and the particle size is the point at which the cumulative volume is 50% on the cumulative curve.
“D90” is the cumulative volume particle size of the powder, which is the volume-based cumulative 90% diameter of the powder obtained in the same manner.
The "monomer-based unit" means an atomic group based on the monomer formed by polymerization of the monomer. The unit may be a unit directly formed by a polymerization reaction, or may be a unit in which a part of the unit is converted into another structure by processing a polymer. Hereinafter, the unit based on the monomer a is also simply referred to as “monomer a unit”.

The production method of the present invention (hereinafter, also referred to as "this method") is modified by subjecting a tetrafluoroethylene polymer (hereinafter, also referred to as "F polymer") to plasma treatment in an atmosphere near atmospheric pressure. It is a method for producing a modified F polymer, which obtains a quality F polymer.

In the first aspect of this method (hereinafter, also referred to as this method 1), the F polymer is a powder (hereinafter, also referred to as raw powder), and the raw powder is plasma-treated in an atmosphere near atmospheric pressure. , A method for producing a modified powder, which modifies the surface of the powder.

The modified powder preferably has a modified layer formed by modifying the F polymer on the surface, and the modified layer is a modified layer formed by introducing a hydrogen atom into the F polymer, or F. It is more preferable that the modified layer is formed by introducing a polymer of a vinyl compound or a vinylidene compound into the polymer.

The modified layer formed by introducing hydrogen atoms into the F polymer is located at 284 eV to 286 eV in the region from the surface to a depth of 1 nm as measured by X-ray photoelectron spectroscopy (hereinafter, also referred to as “ESCA”). The maximum height of the peak (hereinafter, also referred to as “peak H”) is 0.2 times the maximum height of the peak (hereinafter, also referred to as “peak F”) in the region from 289 eV to 295 eV. It is preferably more than that, and more preferably 1 times or more.

QuanteraII (manufactured by ULVAC-PHI) is used for surface measurement by ESCA. A monochromatic AlKα ray is used as the X-ray source at 100 W, and a neutralizing 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 100 μmφ, the photoelectron detection angle is 45 degrees, and the pass. The energy is 55 eV. In addition, the content ratio of fluorine atoms can be calculated from various peak intensities (N1s, O1s, C1s and F1s orbitals) detected by measurement. Further, the depth from the surface can be determined based on the sputtering rate of the _{SiO 2 sputtering film using C60 ions as the sputtering ions.}

Peak H and peak F are, in this order, a photoelectron peak (C1s) based on the 1s orbital of a carbon atom and a photoelectron peak (F1s) based on the 1s orbital of a fluorine atom. In other words, the peak H is a carbon atom and a hydrogen atom. The peak and peak F derived from the single bond (CH bond) of the above can be regarded as the peak derived from the single bond (CF bond) of a carbon atom and a fluorine atom.
In the above region, in addition to peak H and peak F, a photoelectron peak (O1s) based on the 1s orbital of an oxygen atom and a photoelectron peak (N1s) based on the 1s orbital of a nitrogen atom (hereinafter, also referred to as "other peaks"). (Note) is possible.

The content ratio [atm%] of fluorine atoms in the region is preferably 55% or less, and more preferably 40% or less.
The content ratio of fluorine atoms is a value calculated by the following procedure.
In the range including the photoelectron peak of C1s, the photoelectron peak of O1s, the photoelectron peak of N1s and the photoelectron peak of F1s in ESCA, the background is subtracted and each element (carbon atom, oxygen atom, nitrogen atom and fluorine atom) is subtracted. ) Peak intensity is calculated.
The correction value of the peak intensity obtained by dividing the peak intensity by the relative sensitivity coefficient peculiar to the element is obtained for each of the above four elements, and the ratio of the peak intensity (correction value) of the fluorine atom to the total of the correction values is "fluorine atom". Content ratio of ".

The maximum height of the peak H of the surface of the raw powder is preferably less than 0.2 times, more preferably 0.1 times or less of the maximum height of the peak F.
Further, the surface of the raw powder preferably has a fluorine atom content of more than 55%, more preferably 60% or more.
According to this method 1, a modified powder having improved surface physical properties (wetting property, etc.) and dispersion stability can be obtained without impairing the physical properties (electrical physical properties, etc.) of the F polymer as a whole. Its mechanism of action is not always clear, but it is thought to be as follows.

Since the plasma treatment in Method 1 is performed in the vicinity of atmospheric pressure, in other words, in an atmosphere with high gas density, it is considered that the gas contained in the atmosphere is partially converted into plasma. Further, it is considered that the gas contained in the atmosphere not only becomes plasma by itself, but also forms electrically neutral radicals and the like, and also serves as a denaturing component of the polymer.
That is, in the plasma treatment in the present method 1, since the plasma treatment proceeds in such a state, it is considered that the F polymer is easily denatured efficiently.

For example, if the gas contains a reducing gas having a hydrogen atom, it is considered that not only the gas itself becomes a plasma but also an electrically neutral hydrogen radical. As a result, it is considered that hydrogen radicals act on the CF bonds of the F polymer activated by plasma to modify the polymer. In particular, the atomic radius of the hydrogen atom and the atomic radius of the fluorine atom are about the same, and it is considered that this action is more likely to be enhanced.

As a result, according to the present method 1, it is considered that non-fluorine atoms or molecules are efficiently introduced into the F polymer contained on the surface of the raw powder. Further, since the cutting of the F polymer on the surface of the raw powder by plasma is suppressed and the molecular weight reduction thereof is suppressed, the surface state of the modified F polymer is likely to be stable.
According to this method 1, it is considered that a powder having the physical characteristics and excellent surface physical characteristics of the F polymer was obtained by such an action mechanism, and then a liquid composition having excellent dispersibility could be easily prepared.

The fluorine content of the F polymer is preferably 70 to 76% by mass. The F polymer having a high fluorine content is excellent in physical properties (electrical properties, etc.) of the F polymer, but has a particularly low polarity, so that the surface physical properties (wetting property, etc.) of the raw powder are poor. According to this method, even in such a raw powder, a modified powder having improved surface physical properties can be obtained without impairing the physical properties of the entire F polymer.

The melting temperature of the F polymer is preferably 180 ° C. or higher, preferably 200 to 325 ° C., and more preferably 280 to 320 ° C. The glass transition point of the F polymer is preferably 30 to 150 ° C, more preferably 75 to 125 ° C. F-polymers include polytetrafluoroethylene (PTFE), polymers (PFA) containing TFE units and units based on perfluoro (alkyl vinyl ether) (PAVE) (PAVE units), or copolymers containing units based on TFE and hexafluoropropylene (PFA). FEP) is preferred, and PFA or FEP is particularly preferred. These polymers may further contain units based on other comonomeres.

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 F polymer preferably has an atomic group containing an oxygen atom. According to this method, it is easy to obtain a modified molded product having further improved surface physical properties without impairing the physical properties of the F polymer based on the atomic group.

The atomic group may be contained in the monomer 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 the atomic group as a terminal group derived from a polymerization initiator, a chain transfer agent, or the like.
The atomic group containing an oxygen atom is preferably a hydroxyl group-containing group or a carbonyl group-containing group, and a carbonyl group-containing group is particularly preferable.

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)), 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, and an acid anhydride residue. Is particularly preferable.

When the F polymer has a carbonyl group-containing group, the number of carbonyl group-containing groups in the F polymer is preferably 10 to 5000, more preferably 100 to 3000, and more preferably 800, per ^{1 × 10 6 carbon atoms in the main chain.} From 1500 pieces is more preferable. The number of carbonyl group-containing groups in the F polymer can be quantified by the method described in International Publication No. 2020/145133.

Preferable embodiments of the F polymer include a polymer (1) containing TFE units and PAVE units and having atomic groups containing oxygen atoms, or TFE units and PAVE units, and 2 PAVE units for all monomer units. Examples thereof include the polymer (2) containing 0.0 to 5.0 mol% and having no atomic group containing oxygen atoms. Since these polymers form microspherulites in the molded product, the formation of the modified layer according to the first method is more likely to proceed.

The polymer (1) is preferably a polymer containing a TFE unit, a PAVE unit, and a monomer unit having a hydroxyl group-containing group or a carbonyl group-containing group. The polymer (1) has 90 to 99 mol% of TFE units, 0.5 to 9.97 mol% of PAVE units, and 0.01 to 3 mol% of units based on the monomer, respectively, based on all the units. It is preferable to include it.
Further, the monomer is preferably itaconic anhydride, citraconic anhydride or 5-norbornene-2,3-dicarboxylic acid anhydride (also known as hymic anhydride; hereinafter, also referred to as “NAH”).
Specific examples of the polymer (1) include the polymers described in WO 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 monomer units. Is 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 monomer units.
The fact that the polymer (2) does not have an atomic group containing an oxygen atom means that the atomic group containing an oxygen atom contained in the polymer has a ratio ^{of 1 × 10 6 carbon atoms constituting the polymer main chain.} It means that the number is less than 500. The number of atomic groups containing oxygen atoms is preferably 100 or less, more preferably less than 50. The lower limit of the number of atomic groups containing oxygen atoms is usually zero.

The polymer (2) may be produced by using a polymerization initiator, a chain transfer agent, or the like that does not generate an atomic group containing an oxygen atom as a terminal group of the polymer chain, and is an F polymer having an atomic group containing an oxygen atom. May be produced by fluorination treatment. Examples of the fluorination treatment method include a method using fluorine gas (see JP-A-2019-194314, etc.).

The raw powder is preferably composed of an F polymer. The content of the F polymer in the raw powder is preferably 80% by mass or more, and more preferably 100% by mass.
Other components that can be contained in the raw powder include heat-resistant resins such as aromatic polyester, polyamide-imide, thermoplastic polyimide, polyphenylene ether, and polyphenylene oxide. The D50 of the raw powder is preferably 50 μm or less, more preferably 20 μm or less, and further preferably 8 μm or less. The D50 of the raw powder is preferably 0.1 μm or more, more preferably 0.3 μm or more, and even more preferably 1 μm or more. The D90 of the raw powder is preferably less than 100 μm, more preferably 90 μm or less. If the raw powders D50 and D90 are in such a range, the surface area thereof becomes large, and the modification of the raw powder is more likely to proceed.

The plasma treatment in this method 1 is performed in an atmosphere near atmospheric pressure. The pressure near atmospheric pressure is 0.1 ± 0.02 MPa, and the pressure is 0.08 to 0.12 MPa from the viewpoint of controlling the generation of plasma in the atmosphere and enhancing the action of hydrogen-reduced species. From the viewpoint of shielding the outside air and suppressing the mixing of components that inhibit the plasma treatment, it is more preferably atmospheric pressure (0.101325 MPa) or more and 0.12 MPa or less.

The plasma treatment in Method 1 is preferably carried out in an atmosphere containing a reducing gas having a hydrogen atom, a gas containing any one of a vinyl compound and a vinylidene compound. As the reducing gas having a hydrogen atom, hydrogen gas, ammonia gas or hydrocarbon gas is preferable, hydrogen gas, ammonia gas, methane gas or ethylene gas is more preferable, and the viewpoint of the ability to act as a hydrogen reducing species in the above-mentioned action mechanism Therefore, hydrogen gas or ammonia gas is more preferable, and hydrogen gas is most preferable. Two or more types of reducing gas may be used in combination.

The vinyl compound is _{a compound represented by the formula CH 2} = CHR ¹ ^{(R 1} in the formula represents a monovalent organic group), and specific examples thereof include acrylic acid, acrylate, acrylamide, and α-olefin. Examples thereof include (propylene, 1-butene, etc.), vinyl ether, vinyl ester, allyl ether, vinyl chloride, and styrene. The vinyl compound is preferably acrylic acid or acrylate. Two or more kinds of vinyl compounds may be used in combination. The vinylidene compound is a compound represented by the formula CH ₂ = CHR ² R ³ ^{(R 2} and R ³ in the formula each independently represent a monovalent organic group), and a specific example thereof is methacrylamide. , Methacrylate, methacrylamide, vinylidene chloride. The vinyl compound is preferably methacrylic acid or methacrylate. Two or more kinds of vinylidene compounds may be used in combination.

The atmosphere in the plasma treatment may consist of only one of the above gases, or may further contain other gases, and from the viewpoint of controlling the generation of plasma, a reducing gas and further other gases. And are preferably included. The other gas is preferably a water vapor, a nitrogen gas or a rare gas, more preferably a rare gas, further preferably a helium gas, an argon gas or a neon gas, and an argon gas from the above viewpoint. Is the most preferable.

The concentration of the reducing gas having a hydrogen atom in the atmosphere in the plasma treatment or the gas containing any one of the vinyl compound and the vinylidene compound is preferably more than 99% by volume, preferably 99.5% by volume or more. Is more preferable, and 99.9% by volume or more is further preferable. The upper limit of the concentration of the gas is 100% by volume. When the atmosphere contains the gas and the noble gas, the total concentration of the gas and the noble gas may be within the range.
If the gas concentration in the atmosphere is within such a range, the above-mentioned mechanism of action is likely to be enhanced. Such an atmosphere can be formed by using a high-purity gas or a method of shielding air from the atmosphere in the plasma treatment described later.

The gas composition of the atmosphere preferably contains reducing gas in an amount of 0.1% by volume or more, and more preferably more than 1% by volume. The gas composition of the atmosphere preferably contains 100% by volume or less of the reducing gas, and more preferably less than 50% by volume. Preferable specific examples of the gas composition of the atmosphere include a gas composition containing 75 to 99.5% by volume and 0.5 to 25% by volume of a rare gas and a hydrogen gas in this order, and a rare gas and an ammonia gas. In order, a gas composition containing 75 to 99% by volume and 1 to 25% by volume can be mentioned. Moreover, it is preferable that oxygen gas is not contained in these gas compositions.

The plasma treatment in Method 1 is preferably carried out in a gas atmosphere containing a reducing gas having a hydrogen atom, or in a gas atmosphere containing the vinyl compound or vinylidene compound. In the former case, a modified powder formed by introducing hydrogen atoms on the surface of the modified powder was obtained, and in the latter case, a polyvinyl compound chain or a polyvinylidene compound chain was introduced on the surface of the modified powder. Quality powder is obtained.
Examples of the vinyl compound or vinylidene compound include acrylic acid, methacrylic acid, methyl acrylate, and methyl methacrylate, and acrylic acid is preferable. In this case, it is easy to introduce the (meth) acrylic chain and the (meth) acrylate chain densely on the surface of the raw powder.

In this case, the content concentration (volume basis) of the vinyl compound or vinylidene compound in the gas atmosphere is preferably 1200 to 1400 ppm.
Further, the gas atmosphere in this case preferably contains another gas from the viewpoint of controlling the generation of plasma. A preferred embodiment of the other gas is similar to that of the other gas in the above-mentioned atmosphere containing a reducing gas having a hydrogen atom.
When the vinyl compound or vinylidene compound is in a liquid or solid state, it may be heated and used as a gas, or bubbling may be performed to generate a gas.

The plasma treatment in this method 1 is preferably performed in an atmosphere in which air (particularly oxygen gas) is shielded from the viewpoint of suppressing the mixing of components that inhibit the plasma treatment, and in an atmosphere in which the air is completely shielded. It is more preferable to do so.
Examples of the method of shielding air include a method of increasing the atmospheric pressure in plasma processing to atmospheric pressure or higher, and a method of installing an obstacle wall in the plasma processing device to suppress air mixing.

As the method of plasma treatment in this method 1, a method of arranging the raw powder and causing plasma discharge in a plasma chamber filled with a raw material gas such as a reducing gas so as to have atmospheric conditions, or an electrode facing the raw powder. A method of plasma discharge while supplying the raw material gas so as to satisfy the atmospheric conditions can be mentioned.
The voltage during plasma discharge is preferably 5 to 20 kV. The frequency of the power supply during plasma discharge is preferably 50 Hz to 100 MHz. The discharge power density with respect to the electrode area during plasma discharge is preferably ^{1 to 400 W · min / cm 2.} When plasma discharge is performed under the above discharge conditions, the modified molded product tends to have excellent adhesiveness. The discharge time during plasma discharge is preferably 0.1 seconds to 300 minutes with respect to the target raw powder.

The temperature at the time of plasma discharge is preferably 0 to 300 ° C, more preferably 10 to 50 ° C.
When plasma discharge is performed under such conditions, a hydrogen atom or either a polyvinyl compound chain or a polyvinylidene compound chain is more easily introduced into the F polymer existing on the surface of the raw powder containing the F polymer on the surface, and the entire F polymer is easily introduced. It is easy to obtain a modified powder with highly improved surface physical properties such as wettability without impairing the physical properties of hydrogen.
In particular, when the temperature in the plasma discharge is within the above range, a more selective and dense modified layer can be easily formed.

In this method 1, it is preferable to plasma-treat the surface of the raw powder in an atmosphere containing a rare gas in advance before plasma-treating the raw powder. Such pretreatment gives a more highly modified modified powder. Such an atmosphere preferably does not contain reducing gas.

The modified powder obtained by this method 1 has improved surface physical properties such as wettability, and has high dispersibility in a liquid dispersion medium.
The sedimentation rate of the modified powder is preferably 60% or less, more preferably 50% or less, still more preferably 40% or less. The sedimentation rate is a 1.5 μL microtube (model number: 1-7521-01) in which 1.3 μL of a dispersion liquid containing 5% by mass of the modified powder is dispersed in the target liquid dispersion medium. , As One Co., Ltd.), and when centrifuged at 13000 rpm for 5 minutes with a centrifuge, it is a value calculated by the following formula. If no sedimentation component is generated, the sedimentation rate is 0%.
Sedimentation rate [%] = (height of sedimentation component / height of the entire dispersion) × 100

The liquid dispersion medium may be water or a non-aqueous dispersion medium. As the non-aqueous dispersion medium, one or more liquid compounds selected from the group consisting of amides, ketones and esters are preferable, and N-methyl-2-pyrrolidone, γ-butyrolactone, cyclohexanone or cyclopentanone are more preferable.

It is preferable to prepare a liquid composition (hereinafter, also referred to as "the present composition") containing the modified powder obtained by the present method 1 and the liquid composition and in which the modified powder is dispersed.

The content of the modified powder in the present composition is preferably 1 to 60% by mass, more preferably 10 to 50% by mass. The content of the liquid dispersion medium is preferably 40 to 99% by mass, more preferably 50 to 90% by mass. The composition may further contain an inorganic filler or another resin (polymer) different from the F polymer. Since the modified powder has excellent wettability and dispersibility, the composition tends to have excellent dispersion stability even in such a case. In particular, even if PTFE is contained as another resin, it is easy to prepare a liquid composition having a high degree of dispersibility. Such a liquid composition is preferably prepared by mixing a modified powder and an aqueous dispersion containing a PTFE powder.

The viscosity of this composition is more preferably 50 to 1000 mPa · s, more preferably 75 to 500 mPa · s. In this case, the present composition is excellent in coatability. The thixotropy of the present composition is preferably 1.0 to 2.2. In this case, the composition is excellent in coatability and homogeneity. The thixotropy is calculated by dividing the viscosity of the present composition measured under the condition of a rotation speed of 30 rpm by the viscosity of the present composition measured under the condition of a rotation speed of 60 rpm.

This composition has excellent dispersion stability, and can form a molded product having excellent crack resistance and strong adhesiveness to a substrate without impairing the physical characteristics of the F polymer. When this composition is applied to the surface of a base material and heated to form a polymer layer containing an F polymer (hereinafter, also referred to as “F layer (1)”), the base material layer and the F layer can be formed. It is possible to manufacture a laminate having.

In the production of the laminate, the F layer (1) may be formed on at least one side of the surface of the base material, and the F layer (1) may be formed on only one side of the base material, and the F layer (1) may be formed on both sides of the base material. The F layer (1) may be formed. The surface of the base material may be surface-treated with a silane coupling agent or the like. When applying this composition, the 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 , The application method of the slot die coating method can be used.

The F layer (1) is preferably formed by firing a polymer by heating after removing the dispersion medium by heating, and the base material is heated to a temperature (100 to 300 ° C.) at which the dispersion medium volatilizes, and further bases are formed. It is particularly preferable to heat the material in a temperature range (300 to 400 ° C.) at which the polymer is fired. That is, the F layer (1) preferably contains a fired product of PTFE and PFA. The thickness of the F layer (1) is preferably 0.1 μm or more, and more preferably 1 μm or more. The upper limit of the thickness is 100 μm. In this range, the F layer having excellent crack resistance can be easily formed. The peel strength between the F layer (1) and the base material layer is preferably 3 N / cm or more, more preferably 10 N / cm or more, and even more preferably 15 N / cm or more. The peel strength is preferably 100 N / cm or less. By using this composition, such a laminate can be easily formed without impairing the physical characteristics of PTFE in the F layer.

Examples of the material of the base material include copper, aluminum, iron, glass, resin, silicon, and ceramics. Examples of the shape of the base material include a flat shape, a curved surface shape, and an uneven shape, and further, any of a foil shape, a plate shape, a film shape, and a fibrous shape may be used. Specific examples of the laminate include a metal foil, a metal-clad laminate having an F layer (1) on at least one surface of the metal foil, a polyimide film, and an F layer (1) on both surfaces of the polyimide film. A multilayer film having the above 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.

By impregnating the woven fabric with this composition and drying it by heating, an impregnated woven fabric in which the F polymer is impregnated in the woven fabric can be obtained. The impregnated woven fabric can also be said to be a coated woven fabric in which the woven fabric is coated with the F layer (1). The woven fabric is preferably a glass fiber woven fabric, a carbon fiber woven fabric, an aramid fiber woven fabric or a metal fiber woven fabric, and more preferably a glass fiber woven fabric or a carbon fiber woven fabric. The woven fabric may be treated with a silane coupling agent from the viewpoint of enhancing the adhesiveness with the F layer (1). The total content of the F polymer in the main woven fabric is preferably 30 to 80% by mass. Examples of the method of impregnating the woven fabric with the present composition include a method of immersing the woven fabric in the present composition and a method of applying the present composition to the woven fabric.

When the woven fabric is dried, the polymer may be fired. Examples of the method of firing the polymer include a method of passing the woven fabric through a ventilation drying oven in an atmosphere of 300 to 400 ° C. The drying of the woven fabric and the firing of the polymer may be carried out in one step. The impregnated woven fabric is excellent in characteristics such as high adhesion (adhesiveness) between the F layer (1) and the woven fabric, high surface smoothness, and little distortion. By thermocompression bonding the main woven fabric and the metal foil, a metal-clad laminate having high peel strength and resistance to warping can be obtained, which can be suitably used as a printed circuit board material.

Further, the woven fabric impregnated with the present composition is placed on the surface of the base material, heated and dried to form an impregnated woven fabric layer containing the F polymer and the woven fabric, and the base material and the impregnated woven fabric are formed. A laminated body in which the cloth layers are laminated in this order may be produced. The mode is also not particularly limited, and if a woven fabric impregnated with the present dispersion is applied to a part or all of the inner wall surface of a member such as a tank, a pipe, or a container and the member is heated while rotating, the member can be formed. An impregnated woven fabric layer can be formed on a part or all of the inner wall surface of the cloth. This manufacturing method is also useful as a lining method for the inner wall surface of members such as tanks, pipes, and containers.

As described above, the composition has excellent dispersion stability and can be efficiently impregnated into a porous or fibrous material. Examples of such porous or fibrous materials include materials other than the above-mentioned woven fabrics, specifically, plate-like, columnar or fibrous materials. These materials may be pretreated with a curable resin, a silane coupling agent, or the like, or may be further filled with an inorganic filler or the like. In addition, these materials may be twisted to form threads, cables, and wires. At the time of twisting, an interposition layer made of another polymer such as polyethylene may be arranged. An embodiment in which such a material is impregnated with the present composition to produce a molded product includes an embodiment in which the curable resin or a fibrous material on which the cured product is supported is impregnated with the present composition.

Examples of the fibrous material include high-strength and low-elongation fibers such as carbon fiber, aramid fiber, and silicon carbide fiber. As the curable resin, a thermosetting resin such as an epoxy resin, an unsaturated polyester resin, or a polyurethane resin is preferable. Specific examples of such an embodiment include a composite cable formed by impregnating a cable in which carbon fibers supported by a thermosetting resin are twisted with the present composition, and further heating the cable to fire an F polymer. Such a composite cable is useful as a cable for large structures, ground anchors, oil drilling, cranes, cableways, elevators, agriculture, forestry and fisheries, and slinging cables.

In the second aspect of the production method of the present invention (hereinafter, also referred to as "the present method 2"), the surface layer of a molded product (hereinafter, also referred to as an original molded product) having at least a part of the surface layer containing the F polymer is used. Production of a modified molded product having a modified layer formed by introducing hydrogen atoms into an F polymer on at least a part of the surface, which is subjected to plasma treatment in an atmosphere near atmospheric pressure containing a reducing gas having hydrogen atoms. The method.

The maximum height of the peak H of the modified layer in this method 2 is preferably 0.2 times or more, more preferably 1 time or more, with respect to the maximum height of the peak F.
The peak H and the peak F are the same as described above.

The fluorine atom content ratio [atm%] in the region is preferably 55% or less, more preferably 40% or less.
The content ratio of fluorine atoms and the procedure are the same as described above.

The maximum height of the peak H of the surface of the original molded product is preferably less than 0.2 times, more preferably 0.1 times or less of the maximum height of the peak F. ..
Further, the surface of the original molded product preferably has a fluorine atom content of more than 55%, more preferably 60% or more.

According to this method 2, at least one modified layer which is a molded product containing an F polymer and has excellent surface physical properties (wetability, etc.) without impairing the F polymer physical properties (electrical properties, etc.) as a whole. A modified molded product having a portion is obtained. Its mechanism of action is not always clear, but it is thought to be as follows.
Since the plasma treatment in this method 2 is performed in the vicinity of atmospheric pressure, in other words, in an atmosphere with a high gas density, it is considered that the gas contained in the atmosphere is partially converted into plasma. Further, the reducing gas having a hydrogen atom contained in the atmosphere is considered not only to be a plasma itself but also to be an electrically neutral hydrogen radical.

That is, in the plasma treatment in this method 2, it is considered that plasma and hydrogen radicals are present. Since the plasma treatment proceeds in such a state, it is considered that hydrogen radicals act on the CF bonds of the F polymer activated by the plasma to form a modified layer. In particular, the atomic radius of the hydrogen atom and the atomic radius of the fluorine atom are about the same, and it is considered that this action is more likely to be enhanced and the modified layer is efficiently formed.

As a result, according to the present method 2, it is considered that a modified layer in which hydrogen atoms are efficiently introduced into the F polymer contained in the surface of the molded product is formed. Further, it is considered that the cleavage of the F polymer by plasma is suppressed by the action of hydrogen radicals and the reduction in molecular weight thereof is suppressed, so that a highly stable modified layer is formed.
According to this method 2, a modified layer formed by introducing hydrogen atoms into the F polymer is formed on the surface of the molded product containing the F polymer on the surface layer by such an action mechanism, and the physical properties of the F polymer of the entire molded product are formed. It is considered that a modified molded product, which is a molded product of an F polymer, having both a surface physical property and a surface physical property can be obtained.

The thickness of the modified layer in the modified molded product is preferably less than 1000 nm, more preferably 500 nm or less, and particularly preferably 100 nm or less. The thickness of the modified layer is preferably 1 nm or more. The thickness of the modified layer is the length in the direction perpendicular to the plane when the modified layer has a planar spread, and the shortest length when there is no planar spread. Is.

The definition and scope of the F polymer in this method 2 are as described above.

The original molded product in this method 2 is a molded product containing an F polymer on the surface layer. The surface layer of the molded product is a region in the range of at least approximately 1000 nm from the surface of the molded product in the thickness direction of the molded product, and the molded product to which this method 2 is applied is a molded product containing an F polymer in the surface layer. It is a thing. Similar to the above, the thickness of the molded product is the length in the direction perpendicular to the plane when the molded product has a planar spread, and the shortest length when there is no planar spread. Is.
The original molded product may contain the F polymer as a whole, or may contain the F polymer only in the surface layer. Further, in the latter case, the F polymer may be contained in the entire surface layer, or the F polymer may be contained in a part of the surface layer surface.
The surface shape of the original molded product may be smooth or uneven.

The original molded product is preferably a molded product having a layer containing an F polymer on the surface layer, and preferably a sheet-shaped molded product having a layer portion containing the F polymer on the surface layer.
The thickness of the layer containing the F polymer in the surface layer is preferably 1 μm or more, more preferably 5 μm or more, and particularly preferably 10 μm or more. The thickness of the layer containing the F polymer is preferably 1 mm or less. If the surface layer having such a thickness of the original molded product has a layer portion containing the F polymer, it is easy to obtain a modified molded product having the physical characteristics and the surface physical characteristics of the F polymer of the entire molded product by this method.

The original molded product has an F polymer film or a layer containing a base material layer and an F polymer (hereinafter, also referred to as “F layer (2)”), and has an F layer (2) on the surface. Is preferable. In the case of an F polymer film or a laminate having an F layer (2) on both sides, this method may be applied to both sides, and this method may be applied to only one side.
The F polymer film preferably contains the F polymer as a main component, and preferably contains the F polymer in an amount of more than 50% by mass and 100% by mass or less.

Other components that can be contained in the F polymer film include heat-resistant resins such as epoxy resin, maleimide resin, urethane resin, polyimide resin, polyamideimide resin, polyphenylene ether resin, polyphenylene oxide resin, and liquid crystal polyester resin, and nitride filler. , Silica fillers, mica fillers, clay fillers, inorganic fillers such as talc fillers, carbon fillers such as carbon fibers, and polymers.

The base material layer in the laminate is preferably a resin substrate layer or a metal substrate layer.
Examples of the metal substrate layer include metal foil, and examples of the material thereof include copper, nickel, aluminum, titanium, and alloys thereof.
Examples of the resin substrate include a resin film, and the materials thereof include polyimide, polyarylate, polysulfone, polyallyl sulfone, polyamide, polyetheramide, polyphenylene sulfide, polyallyl ether ketone, polyamideimide, liquid polyester, and liquid crystal. Polyester amide can be mentioned. Further, as an embodiment of the resin substrate, a prepreg which is a precursor of the fiber reinforced resin substrate can also be mentioned.

Preferable embodiments of the laminate include a metal-clad laminate having a metal foil and an F layer (2) formed on at least one surface thereof, and a resin film and an F layer (2) formed on at least one surface thereof. ), And examples thereof.
The metal foil in the metal-clad laminate is preferably a copper foil. Such a metal-clad laminate is particularly useful as a printed circuit board material. The resin film in the multilayer film is preferably a polyimide film. Such a multilayer film is useful as an electric wire coating material and a printed circuit board material.

The plasma treatment in this method 2 is performed in an atmosphere containing a reducing gas having a hydrogen atom.
As the reducing gas having a hydrogen atom, hydrogen gas, ammonia gas or hydrocarbon gas is preferable, hydrogen gas, ammonia gas, methane gas or ethylene gas is more preferable, and the viewpoint of the ability to act as a hydrogen reducing species in the above-mentioned action mechanism Therefore, hydrogen gas or ammonia gas is more preferable, and hydrogen gas is most preferable. As the reducing gas, one type may be used alone, or two or more types may be used in combination.

The atmosphere in the plasma treatment may consist of only the reducing gas or may contain other gases, and may include the reducing gas and further other gases from the viewpoint of controlling the generation of plasma. Is preferable. The other gas is preferably a water vapor, a nitrogen gas or a rare gas, more preferably a rare gas, further preferably a helium gas, an argon gas or a neon gas, and an argon gas from the above viewpoint. Is the most preferable.

The concentration of the reducing gas in the atmosphere in the plasma treatment (when the atmosphere contains the gas and the rare gas, the total concentration of the gas and the rare gas) is preferably more than 99% by volume, preferably 99.5% by volume. It is more preferably 99.9% by volume or more, and further preferably 99.9% by volume or more. The upper limit of the concentration of the gas is 100% by volume. If the gas concentration in the atmosphere is within such a range, the above-mentioned mechanism of action is likely to be enhanced. Such an atmosphere can be formed by using a high-purity gas or a method of shielding air from the atmosphere in the plasma treatment described later.

The plasma treatment in this method 2 is performed in an atmosphere near atmospheric pressure. The pressure near atmospheric pressure is 0.1 ± 0.02 MPa, and the pressure is 0.08 to 0.12 MPa from the viewpoint of controlling the generation of plasma in the atmosphere and enhancing the action of hydrogen-reduced species. From the viewpoint of shielding the outside air and suppressing the mixing of components that inhibit the plasma treatment, it is more preferably atmospheric pressure (0.101325 MPa) or more and 0.12 MPa or less.

The plasma treatment in this method 2 is preferably performed in an atmosphere in which air, particularly oxygen gas, is shielded from the viewpoint of suppressing contamination of components that inhibit the plasma treatment, and is performed in an atmosphere in which air is completely shielded. Is more preferable.
Examples of the method of shielding air include a method of increasing the atmospheric pressure in plasma processing to atmospheric pressure or higher, and a method of installing an obstacle wall in the plasma processing device to suppress air mixing.

As the method of plasma treatment in this method 2, a method of arranging the original molded product and plasma discharge in a plasma chamber filled with a raw material gas such as a reducing gas so as to have atmospheric conditions, or a method of facing the original molded product. An example is a method in which the gas is placed between the electrodes and plasma is discharged while supplying the raw material gas so as to satisfy the atmospheric conditions.
The voltage during plasma discharge is preferably 5 to 20 kV. The frequency of the power supply during plasma discharge is preferably 50 Hz to 100 MHz. The discharge power density with respect to the electrode area during plasma discharge is preferably ^{1 to 400 W · min / cm 2.} When plasma discharge is performed under the above discharge conditions, the modified molded product tends to have excellent adhesiveness.
The discharge time during plasma discharge is preferably 0.1 seconds to 300 minutes with respect to the target original molded product.

The temperature at the time of plasma discharge is preferably 0 to 300 ° C, more preferably 10 to 50 ° C.
When plasma discharge is performed under such conditions, hydrogen atoms are more likely to be introduced into the F polymer existing on the surface of the molded product containing the F polymer on the surface layer, and the surface physical properties such as wettability are not impaired without impairing the physical properties of the entire F polymer. It is easy to obtain a modified molded product with a high degree of improvement.
In particular, when the temperature in the plasma discharge is within the above range, a more selective and dense modified layer can be easily formed.

In this method 2, the surface of the original molded product may be plasma-treated in advance in an atmosphere that does not contain a reducing gas before the original molded product is plasma-treated. If the surface of the original molded product is appropriately roughened by such treatment, the contact surface between the surface of the molded product and the plasma in the plasma treatment of this method becomes large, and a modified layer in which hydrogen atoms are introduced to a higher degree is formed. Cheap. Such an atmosphere preferably contains a noble gas.

When the original molded product is the above-mentioned laminate and further laminates it with another base material, the F layer (2) of the original molded product may be subjected to this method 2 to form a modified layer, and then laminated. Adhesion strength with other substrates can be increased. For example, a liquid composition containing F polymer powder is applied to a long base material and heated to form an F layer (2) to prepare an original molded product, and this method 2 is applied to the F layer (2). A long composite base material can be easily obtained by laminating with another long base material by a roll-to-roll process.

When the original molded product is a long roll-shaped laminate, the original molded product is unwound from the roll, and the raw material gas is supplied so as to satisfy the atmospheric conditions while passing the original molded product between the electrodes facing each other. By plasma discharge while allowing the modified layer to be formed, a modified molded product having a modified layer formed can be obtained. The obtained modified molded product may be sent as it is to a laminating step with another base material, or may be wound up in a roll shape and then unwound again and sent to a laminating step with another base material. good. From the viewpoint of simplifying the process, it is preferable to incorporate the discharge device for discharging the plasma into the laminating device so that the original molded product can be plasma-treated before the laminating process.

The modified molded product of the present invention (hereinafter, also referred to as “this molded product”) has a modified layer formed by introducing a hydrogen atom into an F polymer on at least a part of the surface of the modified molded product. Is a layer in which the maximum height of the H peak is 0.2 times or more the maximum height of the F peak, and the content ratio of fluorine atoms in the region is 55% or less. It is a thing. The present molded product is preferably produced by the present method 2.

The mode of the F polymer in the present molded product is the same as that in the present method 1, including the preferred mode. The aspect of the modified layer in the present molded product and the aspect of the state or shape of the surface in the present molded product are the same as those in the present method 2, including the preferred embodiment. A preferred embodiment of the molded product includes a film having a modified layer on at least one surface of the F polymer film, a metal foil, and an F layer (2) formed on at least one surface thereof. It has a metal-clad laminate having a modified layer on the surface of the F layer (2), a resin film, and an F layer (2) formed on at least one surface thereof, and a modified layer is provided on the surface of the F layer. A multilayer film having a structure can be mentioned. When the F layer is formed on both sides of the metal-clad laminate, or when the F layer (2) is formed on both sides of the multilayer film, the modified layer may be provided on both surfaces. ..
The aspects of the F polymer film, the metal leaf, the resin film, and the F layer (2) in these embodiments are the same as those in the present method 1 including the preferred embodiments.

This molded product is a molded product having the physical characteristics of the F polymer of the entire molded product and the surface physical characteristics derived from high polarity, and is particularly useful as an electric wire coating material and a printed circuit board material.
For example, the dielectric constant of the F polymer film having the modified layer or the F layer (2) is preferably 2.0 to 3.5, and more preferably 2.0 to 3.0. The dielectric constant is measured using a split post dielectric resonator (SPDR) at a frequency of 10 GHz in an environment of 23 ° C. ± 2 ° C. and a relative humidity of 50 ± 5%. When the molded product is a multilayer film, the dielectric constant of the molded product is preferably 2.0 to 3.5, more preferably 2.0 to 3.0. The water contact angle of the outermost surface (modified layer) of the molded product is preferably 100 ° or less, more preferably 90 ° or less. The water contact angle of the outermost surface (modified layer) of the molded product is preferably 10 ° or more, more preferably 30 ° or more. The water contact angle is a value measured by the intravenous drip method described in JIS R 3257: 1999.

The surface of the molded product having the modified layer can be further laminated with another base material and adhered. At this time, the peel strength at the interface between the molded product and another base material to be laminated is preferably 8 N / cm or more, and more preferably 10 N / cm or more.

Examples of the method for laminating and adhering the present molded product to other base materials include a method using a hot press. The temperature of the hot press is preferably not more than the melting point of the F polymer, more preferably 300 ° C. or less, still more preferably 240 ° C. or less. The temperature of the hot press is preferably 120 ° C. or higher, more preferably 160 ° C. or higher. Since this molded product has a modified layer having excellent physical properties such as wettability on its surface, it can be laminated and adhered to other base materials at a lower temperature.
Examples of other substrates include prepregs, glass substrates, and ceramic substrates, in addition to the metal and resin substrates described above.

The structure of the laminate of this molded product and other base material is as follows: metal substrate / main molded product having modified layers on both sides / other base material layer / main molded product having modified layers on both sides / metal substrate , Metal substrate layer / other substrate layer / present molded product having modified layers on both sides / other substrate layer / metal substrate layer and the like. Each layer may further contain a glass cloth or filler.
Such laminates are useful as antenna parts, printed substrates, aircraft parts, automobile parts, sports equipment, food industry supplies, paints, cosmetics, etc. Specifically, wire coating materials (aircraft wires, etc.), Electrical insulation tape, insulation 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 (lithium II) For next 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.) Etc.), tools (shovels, shavings, cuttings, saws, etc.), boilers, hoppers, pipes, ovens, baking molds, chutes, dies, toilet bowls, container covering materials.

Although the present method, the present methods 1 and 2, and the present molded product have been described above, the present invention is not limited to the configuration of the above-described embodiment.
For example, the present method, the present methods 1 and 2, 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. Further, in the configuration of the above-described embodiment, the present molded product may be added with any other configuration or may be replaced with an arbitrary configuration exhibiting the same function.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.
[Example 1] Production example of modified powder and liquid composition The following raw materials were used.
F powder 1: Powder composed of polymer 1 (melting point: 300 ° C., fluorine content: 71% by mass) containing 97.9 mol% of TFE units, 2.0 mol% of PPVE units and 0.1 mol% of NAH units. (Average particle size: 2.6 μm). The F powder 1 corresponds to the resin powder (A) described in paragraph number 0154 of the pamphlet of International Publication No. 2018/016644.
F powder 2: Powder consisting of polymer 2 (melting point: 300 ° C., fluorine content: 71% by mass) containing 98.7 mol% of TFE units and 1.3 mol% of PPVE units (average particle size: 4.3 μm) ..
Incidentally, the polymer 1 has a main chain number 1 × 10 1000 to ^six per carbon carbonyl group-containing group, polymers 2 to 40 Yes main chain carbon atoms 1 × 10 ⁶ cells per a carbonyl group-containing group.

[Example 1-1] Production example of modified powder 1 and liquid composition 1 A stage in which a dielectric is sandwiched between a pair of counter electrodes and a mechanism capable of generating plasma by a dielectric barrier discharge is provided to hold the powder. F powder 1 was uniformly installed in the plasma chamber provided with the above. A mixed gas containing 95% by volume of Ar gas and 5% by volume of hydrogen gas is flowed through the chamber to shield the outside air, and the total concentration of Ar gas and hydrogen gas in the chamber during plasma treatment is increased to 99.9% by volume or more. The pressure in the chamber was maintained at 0.1 MPa, and the temperature in the chamber was maintained at 25 ° C. The processing frequency was 13 kHz and the applied voltage was 9 kV. Plasma discharge was performed in the chamber, and F powder 1 was plasma-treated for 1 minute to obtain modified powder 1.
67 parts by mass of distilled water was added to 33 parts by mass of the modified powder 1, and the mixture was stirred for 60 minutes to contain the modified powder 1 and water, and the modified powder 1 containing no surfactant was dispersed. The liquid composition 1 was obtained.

[Example 1-2] Evaluation example With respect to 33 parts by mass of F powder 1, 1 part by mass of a nonionic fluorine-based surfactant (Futergent 250 manufactured by Neos) and 66 parts by mass of distilled water are formed. The mixed solution was added and stirred for 60 minutes to obtain a liquid composition C1 in which the powder 1 was dispersed. The liquid composition C1 corresponds to the dispersion liquid (C-1) described in paragraph No. 0156 of the International Publication No. 2018/016644 pamphlet. As a result of evaluating the "dispersibility" described in Examples of the International Publication No. 2018/016644 pamphlet with respect to the liquid composition 1 and the liquid composition C1, both liquid compositions showed the same dispersibility.

[Example 1-3] Production example of modified powder 2 and liquid composition 2 The modified powder 2 is obtained in the same manner as in Example 1-1 except that the F powder 1 is changed to the F powder 2, and the liquid composition is obtained. I got the thing 2.
[Example 1-4] Production example of modified powder 3 and liquid composition 3 F powder 1 is changed to F powder 2 with Ar gas in a chamber during plasma treatment without particularly shielding the outside air in plasma discharge. The modified powder 3 was obtained in the same manner as in Example 1-1 except that the total concentration of hydrogen gas was less than 99.9% and the oxygen gas was more than 1% by volume, and the liquid composition 3 was obtained. ..

[Example 1-5] Evaluation Example A liquid composition C2 was prepared in the same manner as in Example 1-2 except that F powder 1 was changed to F powder 2.
For each of the liquid compositions 2, 3 and C2, the adhesiveness of the molded product was evaluated by the following procedure.
Each liquid composition is applied to a copper foil by a die coating method, passed through a drying oven at 120 ° C. for 5 minutes to form a dry film on the surface of the copper foil, and further passed through a far-infrared ray furnace at 380 ° C. for 10 minutes. , The polymer was fired to prepare a laminate in which a polymer layer (thickness 10 μm) was formed on the surface of the copper foil. A rectangular test piece having a length of 100 mm and a width of 10 mm was cut out from this laminated body, and the copper foil was peeled from the polymer layer from one end in the length direction of the test piece to a position of 50 mm.
When peeling, the test piece is peeled 90 degrees at a tensile speed of 50 mm / min using a tensile tester (manufactured by Orientec) with the position 50 mm from one end in the length direction as the center, and the measurement distance is from 10 mm to 30 mm. The peel strength (N / cm) of the laminated body was evaluated by measuring the average load of.
The peel strength of the laminate formed from the liquid composition 2 is 8 N / cm, the peel strength of the laminate formed from the liquid composition 3 is 4 N / cm, and the peel strength of the laminate formed from the liquid composition C2 is 4 N / cm. The peel strength of was less than 3 N / cm.

[Example 2] Production example of modified film The following raw materials were used.
Film 1: Film of F polymer 1 (thickness: 25 μm).
Film 2: A film (thickness: 25 μm) of Polymer 3 (melting point: 305 ° C., fluorine content: 71% by mass) containing 98.2 mol% of TFE units and 1.8 mol% of PPVE units.
In each of the film 1 and the film 2, the peak H of the film measured by ESCA (the peak at 284 eV to 286 eV in the region from the surface of the film to the depth of 10 nm) is weak, and the maximum height of the peak H is high. Is well less than 0.2 times the maximum height of peak F (peaks at 289 eV to 295 eV in the region from the surface of the film to a depth of 10 nm), and the fluorine atom content is 60%. there were.

QuanteraII (manufactured by ULVAC-PHI) was used for the surface measurement by ESCA. A monochromatic AlKα ray is used as the X-ray source at 100 W, and a neutralizing 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 100 μmφ, the photoelectron detection angle is 45 degrees, and the pass. The energy was 55 eV. In addition, the content ratio of fluorine atoms was calculated from various peak intensities (N1s, O1s, C1s and F1s 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.

[Example 2-1] Production example of modified film 1 The film 1 is installed in a plasma chamber equipped with a mechanism capable of generating plasma by a dielectric barrier discharge by sandwiching a dielectric in each of a pair of counter electrodes. .. A mixed gas containing 95% by volume of Ar gas and 5% by volume of hydrogen gas was flowed through the chamber to shield the outside air, and the pressure inside the chamber was maintained at 0.1 MPa and the temperature inside the chamber was maintained at 25 ° C. The processing frequency was 13 kHz, the applied voltage was 9 kV, plasma discharge was performed in the chamber, and the film 1 was plasma-treated for 2 minutes.

On the surface of the obtained film (modified film 1), the maximum height of the peak H is 2.5 times the maximum height of the maximum height of the peak F, and the content ratio of fluorine atoms in the region is It was 30%. Further, when the surface of the modified film 1 is etched by 100 nm in the thickness direction and the surface is measured again by ESCA, the profile is the same as that of the film 1, and the modified film 1 has a polymer 1 on the surface. It was confirmed that the film had a modified layer formed by introducing hydrogen atoms.

[Example 2-2] Production example of modified film 2 Example 1 except that the gas sealed in the chamber is changed to a mixed gas containing 94% by volume of Ar gas, 5% by volume of ammonia gas, and 1% by volume of water vapor. The film 1 was subjected to plasma treatment in the same manner as in the above.
On the surface of the obtained film (modified film 2), the maximum height of the peak H is 0.2 times the maximum height of the maximum height of the peak F, and the modified film 2 has a polymer on the surface. It was confirmed that the film had a modified layer formed by introducing a hydrogen atom into 1.

[Example 2-3] Production example of modified film 3 The film 2 was plasma-treated in the same manner as in Example 1 except that the film 1 was made into a film 2.
On the surface of the obtained film (modified film 3), the maximum height of the peak H is three times the maximum height of the maximum height of the peak F, and the content ratio of fluorine atoms in the region is 25. %, And it was confirmed that the modified film 3 is a film having a modified layer formed by introducing hydrogen atoms into the polymer 2 on the surface.

[Example 2-4] Production example of modified film 4 (comparative example)
The film 1 was plasma-treated in the same manner as in Example 1 except that the gas sealed in the chamber was only Ar gas.
The surface condition of the obtained film (modified film 4) measured by ESCA was almost the same as that of film 1.

[Example 2-5] Production example of modified film 5 (comparative example)
The film 1 was plasma-treated in the same manner as in Example 1 except that the conditions were vacuum.
The surface condition of the obtained film (modified film 5) measured by ESCA was almost the same as that of film 1.

[Example 2-6] Evaluation example of modified film The modified film 1 and the solid copper foil are placed facing each other and heat-pressed (temperature: 340 ° C., pressing force: 15 kN / m) to obtain the modified film. An adhesive laminate of 1 and copper foil was obtained. A rectangular test piece having a length of 100 mm and a width of 10 mm was cut out from this adhesive laminate and allowed to stand at 25 ° C. for 3 months. Next, the copper foil layer was peeled from the modified film 1 layer from one end in the length direction of the test piece to a position of 50 mm. When peeling, the test piece is peeled 90 degrees at a tensile speed of 50 mm / min using a tensile tester (manufactured by Orientec) with the position 50 mm from one end in the length direction as the center, and the measurement distance is 10 mm to 30 mm. The average load up to was measured and used as the peel strength (N / cm).
For each film, an adhesive laminate was prepared in the same manner, and the peel strength thereof was evaluated. The results are summarized in Table 1.

As is clear from the above results, the modified powder prepared by this method is difficult to settle, and even if no surfactant is added, the dispersibility in water is equivalent to that when the surfactant is added. You can see that it shows. Further, the molded product formed from the liquid composition containing the modified powder prepared by this method has higher adhesion to the base material than the molded product formed from the liquid composition containing the original powder. It can be seen that it shows high adhesiveness.
From the above, it can be seen that the modified powder by this method is highly surface-modified, and the composition containing the modified powder has liquid physical properties such as dispersibility without adding a surfactant. It can be seen that the liquid composition is excellent and a molded product having high substrate adhesiveness can be formed.
The liquid composition containing the modified powder according to this method is a liquid composition having excellent liquid physical characteristics such as dispersibility, and can be efficiently impregnated into a porous or fibrous material.

Further, as is clear from the above results, when the modified films 1 to 3 which are the modified molded products prepared by this method and the copper foil are adhered, the films 1 or 2 which are the original molded products and the copper foil are adhered to each other. Since it is higher than the peel strength, it can be seen that the adhesion strength is improved. Further, the peel strength between the modified films 1 to 3 produced by this method and the copper foil is higher than the peel strength between the modified films 4 and 5 produced by this method and the copper foil. From the above, it can be seen that the modified molded product according to this method is highly surface-modified.
Therefore, it is considered that the laminate of the modified molded product and other base materials according to this method is useful as antenna parts, printed circuit boards, aircraft parts, automobile parts, sports equipment, food industry supplies, paints, cosmetics, etc. Be done.

Claims

A method for producing a modified tetrafluoroethylene polymer, which comprises plasma-treating a tetrafluoroethylene polymer in an atmosphere near atmospheric pressure to obtain a modified tetrafluoroethylene polymer.
A method for producing a modified powder, in which a tetrafluoroethylene polymer powder is plasma-treated in an atmosphere near atmospheric pressure to modify the surface of the powder.
The second aspect of the present invention, wherein the powder is plasma-treated in an atmosphere near atmospheric pressure containing a reducing gas having a hydrogen atom to obtain a powder formed by introducing a hydrogen atom into the tetrafluoroethylene polymer. Manufacturing method.
The manufacturing method according to any one of claims 2 or 3, wherein the plasma treatment is performed in an atmosphere in which air is shielded.
The production method according to any one of claims 2 to 4, wherein the powder is plasma-treated in advance in an atmosphere containing a rare gas before the plasma treatment is performed.
The production method according to any one of claims 2 to 5, wherein the atmosphere contains at least one gas of a reducing gas having a hydrogen atom, a vinyl compound and a vinylidene compound.
The production method according to any one of claims 2 to 6, wherein the tetrafluoroethylene polymer is a tetrafluoroethylene polymer having a fluorine content of 70 to 76% by mass.
The production method according to any one of claims 2 to 7, wherein the tetrafluoroethylene polymer has an atomic group containing an oxygen atom.
A liquid composition containing the modified powder obtained by the production method according to any one of claims 2 to 8 and a liquid dispersion medium, in which the modified powder is dispersed.
The surface layer of a molded product having at least a part of the surface layer containing a tetrafluoroethylene-based polymer is plasma-treated in an atmosphere near atmospheric pressure containing a reducing gas having a hydrogen atom. The tetrafluoroethylene-based polymer has a hydrogen atom. A method for producing a modified molded product having a modified layer formed by introducing a hydrogen atom on at least a part of the surface.
The manufacturing method according to claim 10, wherein the plasma treatment is performed in an atmosphere in which air is shielded.
The production method according to claim 10 or 11, wherein the surface layer is plasma-treated in advance in an atmosphere that does not contain a reducing gas before the plasma treatment is performed.
The production method according to claim 12, wherein the reducing gas is hydrogen gas, ammonia gas, or hydrocarbon gas.
The production method according to any one of claims 10 to 13, wherein the tetrafluoroethylene polymer has an atomic group containing an oxygen atom.
It has a modified layer formed by introducing hydrogen atoms into a tetrafluoroethylene polymer on at least a part of the surface, and the modified layer has a depth of 1 nm from the surface measured by X-ray photoelectron spectroscopy. The maximum height of the peak at 284 eV to 286 eV in the region is 0.2 times or more the maximum height of the peak at 289 eV to 295 eV in the region, and the content ratio of fluorine atoms in the region is 55. % Or less, a modified molded product containing a tetrafluoroethylene-based polymer.