JP7396301B2 - Powder dispersion liquid, laminate manufacturing method, polymer film manufacturing method, and covering woven fabric manufacturing method - Google Patents

Description

The present invention relates to a powder dispersion, a method for producing a laminate, a method for producing a polymer film, and a method for producing a covered woven fabric.

Fluoroolefin polymers such as polytetrafluoroethylene (PTFE), a copolymer of tetrafluoroethylene and perfluoro(alkyl vinyl ether) (PFA), and a copolymer of tetrafluoroethylene and hexafluoropropylene (FEP) have excellent mold releasability and electrical properties. It has excellent physical properties such as water and oil repellency, chemical resistance, weather resistance, and heat resistance, and is used in a variety of industrial applications by taking advantage of its physical properties.
Among these, a powder dispersion in which fluoroolefin polymer powder is dispersed in a solvent is useful as a coating agent because it can impart the physical properties of a fluoroolefin polymer to the surface of various substrates when applied to the surface. (See Patent Documents 1 and 2).

International Publication No. 2018/016644 International Publication No. 2008/018400

Each fluoroolefin polymer has unique properties.
Non-thermofusible polytetrafluoroethylene is known to have unique physical properties represented by fibrillarity. It is believed that by using a dispersion of a mixture of non-thermofusible polytetrafluoroethylene powder and thermofusible fluoroolefin polymer powder such as PFA or FEP, it is possible to form a molded article that has the physical properties of both polymers. Conceivable.
However, such dispersions have low dispersibility and are subjected to dispersion treatment that applies shear stress, etc. in order to adjust the dispersion to a uniform dispersion, redisperse the dispersion after time, or further blend other components. Then, there is a problem that the non-thermofusible polytetrafluoroethylene changes in quality, such as becoming fibrillated, and its dispersibility and moldability deteriorate.

Moreover, molded articles formed from such dispersions still have a problem in that mechanical strength such as crack resistance and adhesion are still insufficient. In particular, crack resistance and adhesion are still insufficient when increasing the thickness of a molded article or when stretching a molded article.

On the other hand, heat-melting fluoropolymers such as modified PTFE, PFA, and FEP have excellent heat resistance, chemical resistance, etc., as well as excellent moldability, just like PTFE. However, the adhesion and processability (stretchability, flexibility such as bendability, etc.) to other materials are still insufficient, and molded products are formed from an aqueous dispersion containing heat-melting fluoropolymer powder. This tendency is remarkable in molded products made by Furthermore, when such an aqueous dispersion is blended with a component for improving adhesiveness or processability, there is a problem that the dispersion state of the dispersion is deteriorated or the physical properties of the fluoropolymer in a molded article are deteriorated.

The present invention includes a powder of non-thermofusible polytetrafluoroethylene or a powder of a thermofusible fluoropolymer and a predetermined tetrafluoropolymer powder, and has excellent processability without impairing the physical properties of both polymers. The object of the present invention is to provide a powder dispersion that can form a molded article exhibiting strong adhesion, a method for producing a laminate using such a powder dispersion, a method for producing a polymer film, and a method for producing a covering fabric.

The present invention has the following aspects.
<1> A fluoropolymer powder (1) having a unit based on tetrafluoroethylene and an oxygen-containing polar group, and a non-thermal melting polytetrafluoroethylene powder (21) or a thermomelting fluoropolymer powder (22). , an aqueous medium.
<2> The volume-based cumulative 50% diameter of the powder (1) is 0.01 to 75 μm, and the volume-based cumulative 50% diameter of the powder (21) or the powder (22) is 0.01 to 100 μm. The powder dispersion according to <1> above.
<3> The above <1>, wherein the ratio by mass of the content of the fluoropolymer to the content of the non-thermofusible polytetrafluoroethylene or the content of the thermofusible fluoropolymer is 0.4 or less. Or the powder dispersion liquid of <2>.
<4> The powder dispersion according to any one of <1> to <3> above, wherein the fluoropolymer has a melting temperature of 140 to 320°C.
<5> The powder dispersion according to any one of <1> to <4> above, wherein the fluoropolymer contains units based on the monomer having the oxygen-containing polar group.
<6> The powder dispersion according to any one of <1> to <5> above, wherein the oxygen-containing polar group is a hydroxyl group-containing group or a carbonyl group-containing group.
<7> The powder dispersion according to any one of <1> to <6> above, wherein the non-thermofusible polytetrafluoroethylene has fibrillar properties.
<8> The above <1> to <7, wherein the heat-melting fluoropolymer is a modified polytetrafluoroethylene, a copolymer of tetrafluoroethylene and perfluoro(alkyl vinyl ether), or a copolymer of tetrafluoroethylene and hexafluoropropylene. > any of the powder dispersions.
<9> The powder dispersion according to any one of <1> to <8> above, which includes both the non-thermofusible polytetrafluoroethylene powder (21) and the thermofusible fluoropolymer powder (22).
<10> The powder dispersion according to any one of <1> to <9> above, further comprising an acetylene surfactant, a silicone surfactant, or a fluorine surfactant.
<11> The powder dispersion according to any one of <1> to <10> above, further comprising a fluorosurfactant, and the fluorosurfactant is a fluoromonool or a fluoropolyol.
<12> The powder dispersion according to any one of <1> to <11> above is applied to the surface of a base material, and the aqueous medium is removed by heating to form a polymer layer, which is composed of the base material. A method for manufacturing a laminate, comprising obtaining a laminate in which a base material layer and the polymer layer are laminated in this order.
<13> The powder dispersion according to any one of <1> to <11> above is applied to the surface of a base material, and the aqueous medium is removed by heating to form a polymer layer, which is composed of the base material. Manufacturing a polymer film by obtaining a laminate in which a base material layer and the polymer layer are laminated in this order, and removing the base material layer from the laminate to obtain a polymer film composed of the polymer layer. Method.
<14> Production of a covered woven fabric by impregnating a woven fabric with the powder dispersion according to any one of <1> to <11> above, and further drying the woven fabric to obtain a woven fabric coated with a polymer layer. Method.

According to the present invention, the molded product has excellent state stability such as dispersibility and storage stability, is resistant to cracking, and exhibits strong adhesive properties without impairing the physical properties of non-thermofusible polytetrafluoroethylene. A powder dispersion that has excellent state stability and can form molded products that exhibit strong adhesion and good processability without impairing the physical properties of the heat-melting fluoropolymer. is provided. Further, a method for manufacturing a laminate, a method for manufacturing a polymer film, and a method for manufacturing a covered woven fabric using such a powder dispersion are provided.

"Powder D50" is the volume-based cumulative 50% diameter.The particle size distribution is measured by laser diffraction/scattering method, a cumulative curve is calculated with the total volume of the particle group as 100%, and the cumulative volume is calculated on the cumulative curve. is the particle diameter at the point where is 50%.
"Powder D90" is the volume-based cumulative 90% diameter, and the particle size distribution is measured by laser diffraction/scattering method, a cumulative curve is calculated with the total volume of the particle group as 100%, and the cumulative volume is calculated on the cumulative curve. is the particle diameter at the point where is 90%.
A "unit" in a polymer may be an atomic group formed directly from a monomer by a polymerization reaction, or an atomic group whose structure has been partially converted by treating the polymer obtained by a polymerization reaction in a predetermined manner. It may be. Further, a unit based on monomer A is also referred to as a monomer A unit.
"Viscosity of powder dispersion" is a value measured using a B-type viscometer at room temperature (25° C.) and a rotation speed of 30 rpm. Repeat the measurement three times and use the average value of the three measurements.
The "thixotropic ratio of a powder dispersion" is a value calculated by dividing the viscosity η ₁ measured at a rotation speed of 30 rpm by the viscosity η ₂ measured at a rotation speed of 60 rpm. Each viscosity measurement was repeated three times, and the average value of the three measurements was taken.
The "melting temperature (melting point) of a polymer" is the temperature corresponding to the maximum value of the melting peak of a polymer measured by differential scanning calorimetry (DSC).
"Peel strength of a laminate" refers to a laminate cut into a rectangular shape (length 100 mm, width 10 mm), fixed at a position 50 mm from one end in the longitudinal direction, pulled at a tensile rate of 50 mm/min, and one end in the longitudinal direction. This is the maximum load (N/cm) applied when the metal foil and the resin layer are peeled off at an angle of 90° to the laminate.
"Standard Specific Gravity of a Polymer" is the standard specific gravity of a polymer as measured in accordance with ASTM D 4895.
The "melt flow rate" is the melt mass flow rate (MFR) defined in JIS K 7210-1:2014 (corresponding international standard ISO 1133-1:2011).

The powder dispersion of the present invention (this dispersion) is a powder (1) of a polymer (hereinafter also referred to as "F polymer") having units based on tetrafluoroethylene (TFE) (TFE units) and oxygen-containing polar groups. and powder (21) of non-thermo-fusible polytetrafluoroethylene (hereinafter also referred to as "non-thermo-fusible PTFE") or powder (22) of thermo-fusible fluoropolymer (hereinafter also referred to as "M polymer"). ) and an aqueous medium.
The present dispersion liquid can be said to be a dispersion liquid in which powder (1) and powder (21) or powder (22) are each dispersed in the form of particles in an aqueous medium containing water as a main component.
Note that the F polymer, non-thermofusible PTFE, and M polymer are different polymers.
The molded product formed from this dispersion (including molded parts such as polymer layers; the same shall apply hereinafter) has individual fluorocarbon properties such as the fibrillarity of non-thermal melting PTFE and the processability of heat-melting fluoropolymer. It exhibits strong adhesion and crack resistance while possessing the unique physical properties of polymers.

Although the reason is not necessarily clear, it is thought to be as follows.
In the present dispersion containing the powder (21), the non-thermofusible PTFE and the F polymer are both polymers containing TFE units, and are likely to interact, fuse, and join. In addition, since F polymer has an oxygen-containing polar group, it has high stability in an aqueous medium and interacts with non-thermofusible PTFE, improving the dispersion stability of the powder. Conceivable. As a result, both powders were stabilized and uniformly dispersed in the aqueous medium, so it is considered that the present dispersion has excellent state stability.
Furthermore, during the formation of a molded article, the F polymer having an oxygen-containing polar group is thought to not only exhibit adhesive properties but also promote interaction between the polymers, for example, the formation of a matrix. It is thought that this interaction creates a state in which each polymer chain tends to be uniformly entangled. As a result, it is considered that a molded article with excellent adhesiveness and crack resistance could be formed from this dispersion without impairing the properties of non-thermofusible PTFE.

On the other hand, in the present dispersion containing powder (22), both the M polymer and the F polymer are polymers having fluorine atoms, and thus they are likely to interact, fuse, and join. Furthermore, since the F polymer has an oxygen-containing polar group, it is highly stable in an aqueous medium, and it is thought that it also interacts with the M polymer to improve the dispersion stability of the powder. As a result, both powders were stabilized and uniformly dispersed in the aqueous medium, so it is considered that the present dispersion has excellent state stability.
Furthermore, during the formation of a molded article, the F polymer having an oxygen-containing polar group is thought to not only exhibit adhesive properties but also promote interaction between the polymers, for example, the formation of a matrix. It is thought that this interaction creates a state in which each polymer chain tends to be uniformly entangled. As a result, it is considered that a molded article with excellent adhesiveness and processability could be formed from this dispersion without impairing the properties of the M polymer.

Powder (1) in the present invention is a powder containing F polymer, preferably a powder consisting of F polymer. The content of F polymer in powder (1) is preferably 80% by mass or more, particularly preferably 100% by mass.
D50 of powder (1) is preferably 0.01 to 75 μm, more preferably 0.05 to 6 μm, and even more preferably 0.1 to 4 μm. Preferred embodiments of the D50 of powder (1) include an embodiment in which it is 0.1 μm or more and less than 1 μm, and an embodiment in which it is 1 μm or more and 4 μm or less.
D90 of powder (1) is preferably 8 μm or less, more preferably 6 μm or less. D90 of powder (1) is preferably 0.1 μm or more, more preferably 0.3 μm or more. Preferred embodiments of the D90 of powder (1) include an embodiment in which it is 0.3 μm or more and less than 2 μm, and an embodiment in which it is 2 μm or more and 6 μm or less.
In this case, it is easy to further improve the dispersion stability of the present dispersion and the physical properties of the molded article. For example, if the D50 of the powder (1) is 0.1 μm or more and less than 1 μm, its dispersibility will be better, and a molded article with excellent mechanical strength such as stretching properties will be easily obtained. If the D50 of the powder (1) is 1 μm or more and 4 μm or less, a molded product with excellent crack resistance can be easily obtained.

The oxygen-containing polar group possessed by the F polymer in the present invention may be included in a unit based on a monomer having an oxygen-containing polar group, may be included in a polymer terminal group, and may be included in a surface treatment (radiation treatment, electron beam treatment, treatment, corona treatment, plasma treatment, etc.); the former is preferred. Further, the oxygen-containing polar group possessed by the F polymer may be a group prepared by modifying a polymer having a group capable of forming an oxygen-containing polar group. The oxygen-containing polar group contained in the polymer terminal group can be obtained by adjusting the components (polymerization initiator, chain transfer agent, etc.) used during polymerization of the polymer.
The oxygen-containing polar group is a polar atomic group containing an oxygen atom. However, the oxygen-containing polar group does not include ester bonds and ether bonds themselves, but includes atomic groups containing these bonds as characteristic groups.

The oxygen-containing polar group is preferably at least one group selected from the group consisting of a hydroxyl group-containing group, a carbonyl group-containing group, an acetal group, and an oxycycloalkane group, more preferably a hydroxyl group-containing group or a carbonyl group-containing group, and -CF ₂ CH ₂ OH, -C(CF ₃ ) ₂ OH, 1,2-glycol group (-CH(OH)CH ₂ OH), -CF ₂ C(O)OH, >CFC(O)OH, carboxamide group (-C(O)NH2 _{, etc.} ), acid anhydride residues (-C(O)OC(O)-), imide residues (-C(O)NHC(O)-, etc.), dicarboxylic acid residues (-CH(C(O)OH)CH ₂ C(O)OH, etc.) or carbonate group (-OC(O)O-) is more preferred.
The oxycycloalkane group is preferably an epoxy group or an oxetanyl group.
In addition, from the viewpoint of not impairing the adhesion and crack resistance of the molded product and the physical properties of the polymer, the oxygen-containing polar group is a cyclic acid anhydride residue, which is a polar group and a cyclic group, or a ring-opening group thereof. Cyclic imide residues, cyclic carbonate groups, cyclic acetal groups, 1,2-dicarboxylic acid residues or 1,2-glycol groups are particularly preferred, and cyclic acid anhydride residues are most preferred.

The F polymer includes TFE units and units based on hexafluoropropylene (HFP), perfluoro(alkyl vinyl ether) (hereinafter also referred to as "PAVE"), or fluoroalkyl ethylene (hereinafter also referred to as "FAE") (hereinafter, A polymer containing a unit based on a monomer having an oxygen-containing polar group (hereinafter also referred to as a "polar unit") is preferred.
The proportion of TFE units is preferably 50 to 99 mol%, more preferably 90 to 99 mol% of all units constituting the F polymer.
The PAE unit is preferably a PAVE-based unit or a HFP-based unit, more preferably a PAVE-based unit. There may be two or more types of PAE units.
The proportion of PAE units is preferably 0.5 to 9.97 mol% of all units constituting the F polymer.

As PAVE, CF ₂ =CFOCF ₃ (PMVE), CF ₂ =CFOCF ₂ CF ₃ , CF ₂ =CFOCF ₂ CF ₂ CF ₃ (PPVE), CF ₂ =CFOCF ₂ CF ₂ CF ₂ CF ₃ , CF ₂ =CFO (CF ₂ ) ₈ F is mentioned, with PMVE or PPVE being preferred.
As FAE, _CH2 =CH( _CF2 ) _2F (PFEE), _CH2 =CH( _CF2 ) _3F , _CH2 =CH( _CF2 ) _4F (PFBE), _CH2 =CF( _CF2 ) ₃ H, CH ₂ =CF(CF ₂ ) ₄ H, and PFEE or PFBE is preferred.

The polar unit is preferably a unit based on a monomer having an acid anhydride residue, a carbonate group, a cyclic acetal group, a 1,2-dicarboxylic acid residue, a 1,2-diol residue, or a 1,3-diol residue. , a unit based on a monomer having a cyclic acid anhydride residue or a cyclic carbonate group is more preferable, and a unit based on a monomer having a cyclic acid anhydride residue is even more preferable. The number of polar units may be one type, or two or more types.
The monomer having a cyclic acid anhydride residue is itaconic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride (also known as hymic anhydride; hereinafter also referred to as "NAH") or maleic anhydride. Acids are preferred, and NAH is more preferred.
The proportion of polar units is preferably 0.01 to 3 mol% of all units constituting the F polymer.

Moreover, the F polymer in this case may further contain units other than TFE units, PAE units, and polar units (hereinafter also referred to as "other units"). The number of other units may be one type or two or more types.
Examples of monomers forming other units include ethylene, propylene, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride (VDF), and chlorotrifluoroethylene (CTFE). The other units are preferably ethylene, VDF or CTFE, and more preferably ethylene.
The proportion of other units in the F polymer is preferably 0 to 50 mol%, more preferably 0 to 40 mol% of all units constituting the F polymer.

The melting temperature of polymer F is preferably 140 to 320°C, more preferably 200 to 320°C, even more preferably 260 to 320°C. In this case, the fusion properties of the F polymer and the non-thermo-fusible PTFE are balanced, and while the adhesion and crack resistance of the molded article are further improved, the physical properties of the non-thermo-fusible PTFE are not easily impaired.

The dispersion liquid may contain powder (21) or powder (22), may contain only powder (21), may contain only powder (22), or may contain powder (21) and powder (22). It may contain both.
The powder (21) is a powder containing non-thermofusible PTFE, and is preferably a powder consisting of non-thermofusible PTFE. The content of non-thermofusible PTFE in the powder (21) is preferably 80% by mass or more, more preferably 100% by mass. Note that, in this specification, components (surfactants, etc.) used in the production of non-thermofusible PTFE are not included in components other than non-thermofusible PTFE.
The powder (22) in the present invention is a powder containing an M polymer, and preferably a powder consisting of an M polymer. The content of F polymer in the powder (22) is preferably 80% by mass or more, more preferably 100% by mass.

The D50 of the powder (21) is preferably 0.01 to 100 μm, more preferably 0.1 to 10 μm. A preferred embodiment of the D50 of the powder (21) includes an embodiment in which the D50 is 0.1 to 1 μm.
D90 of the powder (21) is preferably 200 μm or less, more preferably 20 μm or less. D90 of the powder (21) is preferably 0.1 μm or more, more preferably 0.2 μm or more. A specific preferred embodiment of the D90 of the powder (21) is one in which it is 0.1 to 2 μm.
In this case, the dispersibility of the powder (1) and the interaction between the powders become good, making it easier to further improve the physical properties of the dispersion and the molded article.

A preferred aspect of the relationship between the D50 of powder (1) and the D50 of powder (21) is that D50 of powder (1) is 0.1 μm or more and less than 1 μm or 1 μm or more and 4 μm or less; An embodiment in which D50 is 0.1 μm or more and 1 μm or less is mentioned. In the former embodiment, the dispersibility of the present dispersion is excellent, and a molded article with excellent mechanical strength such as stretching properties is easily obtained. In the latter embodiment, a molded product with excellent crack resistance is easily obtained.

The D50 of the powder (22) is preferably 0.01 to 100 μm, more preferably 0.1 to 10 μm. A preferred embodiment of the D50 of the powder (22) is one in which it is 0.1 to 1 μm.
D90 of the powder (22) is preferably 200 μm or less, more preferably 20 μm or less. D90 of the powder (22) is preferably 0.1 μm or more, more preferably 0.2 μm or more. A preferred embodiment of the D90 of the powder (22) includes an embodiment in which the D90 is 0.1 to 2 μm. In this case, the dispersibility of the powder (22) and the interaction with the powder (1) become good, and the adhesion and crack resistance of the molded article and the physical properties of the M polymer tend to improve.

A preferred aspect of the relationship between D50 of powder (1) and D50 of powder (22) is that D50 of powder (1) is 0.1 μm or more and less than 1 μm, or D50 is 1 μm or more and less than 4 μm, and powder (22) Examples include an embodiment in which the D50 is 0.1 μm or more and 1 μm or less. In the former embodiment, the dispersibility of the present dispersion is excellent, and a molded article with excellent mechanical strength such as stretching properties is easily obtained. In the latter embodiment, a molded product with excellent crack resistance is easily obtained.

Non-thermofusible PTFE is polytetrafluoroethylene (PTFE), and in addition to homopolymers of TFE, there are also so-called modified PTFEs, which are copolymers of TFE and extremely small amounts of comonomers (PAVE, HFP, FAE, etc.). Included.
As mentioned above, the molded product obtained from this dispersion not only exhibits strong adhesion and crack resistance, but also exhibits the fibrous surface properties and porosity inherent in non-thermofusible PTFE molded products. Not easily damaged.
The proportion of TFE units in the non-thermofusible PTFE is preferably 99.5 mol% or more, more preferably 99.9 mol% or more of all units.

The non-thermofusible PTFE is preferably a polymer obtained by emulsion polymerization of TFE in water. Such non-thermofusible PTFE powder is a powder in which polymer particles obtained by emulsion polymerization of TFE in water are dispersed in water. When using such a powder, the powder dispersed in water may be used as it is, or the powder may be recovered from the water and used.
Non-thermofusible PTFE is widely available commercially as a powder or a dispersion thereof.
The non-thermofusible PTFE preferably has fibrillar properties. If it has fibrillarity, it will be easier to produce a porous membrane by stretching treatment. Note that non-thermofusible PTFE having fibrillarity means PTFE from which unfired polymer powder can be extruded into a paste. That is, it means PTFE that has strength or elongation in molded products obtained by paste extrusion.

The number average molecular weight of the non-thermofusible PTFE is preferably from 300,000 to 300,000,000, more preferably from 500,000 to 25,000,000.
The standard specific gravity, which is an index of the average molecular weight of non-thermofusible PTFE, is preferably 2.14 to 2.22, more preferably 2.15 to 2.21.
The melt viscosity of the non-thermofusible PTFE at 380° C. is preferably 1×10 ⁹ Pa·s or more. The upper limit of the melt viscosity is usually 1×10 ¹⁰ Pa·s.
If at least one of the number average molecular weight, standard specific gravity, and melt viscosity of the non-thermo-fusible PTFE is within the above range, the fibrillarity of the non-thermo-fusible PTFE will be better, and molding with better mechanical properties etc. products can be formed. Moreover, in this case, the state stability of the present dispersion is more likely to be improved.

The M polymer is a polymer containing a unit based on a fluoroolefin (hereinafter also referred to as "F unit") different from the F polymer, and preferably a polymer containing F units and having no oxygen-containing polar group.
The proportion of F units in the M polymer is preferably 50.0 mol% or more, more preferably 99.5 mol% or more, and even more preferably 99.9 mol% or more of all units.
The fluoroolefin in the M polymer is preferably TFE or VDF, more preferably TFE. Two or more types of fluoroolefins may be used.

The M polymer is preferably a copolymer of TFE and PAVE (PFA), a copolymer of TFE and HFP (FEP), a copolymer of TFE and ethylene (ETFE), a homopolymer of VDF (PVDF), or a low molecular weight PTFE. Molecular weight PTFE is more preferred.
In addition to homopolymers of TFE, low molecular weight PTFE also includes so-called modified PTFE, which is a copolymer of TFE and a very small amount of comonomer (PAVE, HFP, FAE, etc.). PFA may also contain units based on monomers other than TFE and PAVE. The same applies to the other copolymers mentioned above (FEP, ETFE, PVDF).
One suitable embodiment of the M polymer includes low molecular weight PTFE or modified PTFE.

In this case, the melt viscosity of the M polymer at 380° C. is preferably 1×10 ² to 1×10 ⁶ Pa·s, more preferably 1×10 ³ to 1×10 ⁶ Pa·s.
The melting temperature of the polymer in this case is preferably 321 to 340°C, more preferably 325 to 335°C.
The melt flow rate of the polymer in this case is preferably 1 to 10 g/10 minutes, more preferably 1 to 5 g/10 minutes.
If at least one of the melt viscosity, melt flow rate, and melt temperature of the low molecular weight PTFE or modified PTFE is within the above range, a molded article with better physical properties (processability, mechanical strength, etc.) of these PTFEs can be formed. Moreover, in this case, the interaction between the powder (22) and the powder (1) in the present dispersion is improved, and the state stability of the present dispersion is more likely to be improved.

Low molecular weight PTFE is PTFE obtained by irradiating high molecular weight PTFE (melt viscosity is about 1×10 ⁹ to 1×10 ¹⁰ Pa・s) (International Publication No. 2018/026012, International Publication No. 2018 /026017 etc.), or PTFE obtained by adjusting a chain transfer agent when polymerizing TFE to produce PTFE (Japanese Patent Application Laid-open No. 2009-1745, International Publication No. 2010/ 114033, JP-A No. 2015-232082, etc.) may also be used.

A preferred specific example of low molecular weight PTFE includes PTFE whose number average molecular weight (Mn) calculated based on the following formula (1) is 200,000 or less.
Mn = 2.1×10 ¹⁰ ×ΔHc ^-5.16 ... (1)
In formula (1), ΔHc represents the crystallization heat amount (cal/g) of the PTFE measured by differential scanning calorimetry.
Mn of this low molecular weight PTFE is preferably 10 or less, more preferably 50,000 or less. The Mn of this low molecular weight PTFE is preferably 10,000 or more.

Furthermore, one of the preferred embodiments of the M polymer is PFA or FEP.
In this case, the melt viscosity of the M polymer at 380° C. is preferably 1×10 ² to 1×10 ⁴ Pa·s, more preferably 1×10 ² to 1×10 ³ Pa·s.
In this case, the melt flow rate of the M polymer is preferably 5 to 30 g/10 minutes, more preferably 5 to 20 g/10 minutes.
The melting temperature of the M polymer in this case is preferably 260 to 320°C, more preferably 280 to 310°C.
If at least one of the melt viscosity, melt flow rate, and melt temperature of PFA or FEP is within the above range, molded products with excellent physical properties (processability, mechanical strength, etc.) of these PFA or FEP can be formed. However, the state stability of the present dispersion is more likely to be improved.

The M polymer is preferably a polymer obtained by emulsion polymerization of a fluoroolefin in water. Such M polymer powder is a powder in which a polymer obtained by emulsion polymerization of a fluoroolefin in water is dispersed in water as particles. When using such a powder, the powder dispersed in water may be used as it is, or the powder may be recovered from the water and used.
The M polymer may be modified by surface treatment (radiation treatment, electron beam treatment, corona treatment, plasma treatment, etc.). Examples of such surface treatment methods include methods described in International Publication No. 2018/026012, International Publication No. 2018/026017, and the like.
The M polymer is widely available commercially as a powder or a dispersion thereof.

The present dispersion may contain only non-thermofusible PTFE, only M polymer, or both non-thermofusible PTFE and M polymer. Note that each polymer is preferably contained as a powder.
When the present dispersion contains both non-thermofusible PTFE and M polymer, the D50 of the non-thermofusible PTFE powder (powder (21)) is preferably 0.1 to 1 μm, and the D90 is 0.1 to 2 μm. is preferred. Further, in this case, the D50 of the M polymer powder (powder (22)) is preferably 0.1 to 1 μm, and the D90 is preferably 0.1 to 2 μm.

In this case, the ratio by mass of the F polymer content to the non-thermofusible PTFE content or the M polymer content in the present dispersion is preferably 0.4 or less, more preferably 0.15 or less. In this case, the interaction between the powders becomes good, the state stability of the dispersion is further improved, and the adhesion and crack resistance of the molded article and the physical properties between the polymers are easily balanced.
Further, in this case, the total content of non-thermofusible PTFE and M polymer is preferably 20 to 70% by mass, more preferably 30 to 60% by mass.

This dispersion liquid preferably contains a dispersant from the viewpoint of improving the dispersibility of each powder and improving its moldability. Note that the components used in producing the polymer (for example, the surfactants used in emulsion polymerization of fluoroolefins) do not correspond to the dispersant in the present invention.

The dispersant is preferably a compound having a hydrophobic part and a hydrophilic part, and examples thereof include acetylene surfactants, silicone surfactants, and fluorine surfactants. These dispersants are preferably nonionic.
The dispersant is preferably a fluoroalcohol, more preferably a fluoromonool or a fluoropolyol.
The fluorine content of the fluoromonool is preferably 10 to 50% by mass, more preferably 10 to 45% by mass, and even more preferably 15 to 40% by mass.
The fluoromonool is preferably nonionic.
The hydroxyl value of the fluoromonool is preferably 40 to 100 mgKOH/g, more preferably 50 to 100 mgKOH/g, even more preferably 60 to 100 mgKOH/g.

The fluoromonool is preferably a compound represented by the following formula (a).
Formula (a): R ^a -(OQ ^a ) _ma -OH
The symbols in the formula have the following meanings.
R ^a represents a polyfluoroalkyl group or a polyfluoroalkyl group containing an ether oxygen atom, such as -CH ₂ (CF ₂ ) ₄ F, -CH ₂ (CF ₂ ) ₆ F, -CH ₂ CH ₂ (CF ₂ ) ₄ F, -CH ₂ CH ₂ (CF ₂ ) ₆ F, -CH ₂ CF ₂ OCF ₂ CF ₂ OCF ₂ CF ₃ , -CH ₂ CF (CF ₃ ) CF ₂ OCF ₂ CF ₂ CF ₃ , -CH ₂ CF(CF ₃ )OCF ₂ CF(CF ₃ )OCF ₃ or -CH ₂ CF ₂ CHFO(CF ₂ ) ₃ OCF ₃ is preferred.
Q ^a represents an alkylene group having 1 to 4 carbon atoms, and is preferably an ethylene group (-CH ₂ CH ₂ -) or a propylene group (-CH ₂ CH (CH ₃ )-). Q ^a may be composed of two or more types of groups. When it is composed of two or more types of groups, the groups may be arranged in a random manner or in a block manner.
ma represents an integer of 0 to 20, preferably an integer of 4 to 10.
The hydroxyl group of the fluoromonool is preferably a secondary hydroxyl group or a tertiary hydroxyl group, and a secondary hydroxyl group is particularly preferable.

Specific examples of fluoromonool include F(CF ₂ ) ₆ CH ₂ (OCH ₂ CH ₂ ) ₇ OCH ₂ CH(CH ₃ )OH, F(CF ₂ ) ₆ CH ₂ (OCH ₂ CH ₂ ) ₁₂ OCH ₂ CH( _CH3 )OH, F( _CF2 ) _{6 CH2CH2 ( OCH2CH2 ) 7 OCH2CH} ( _CH3 )OH, F( _{CF2 ) 6 CH2CH2} ( _{OCH2CH2 ) 12 Examples} include _OCH2CH ( _CH3 )OH, _F ( _CF2 ) _{4CH2CH2 ( OCH2CH2 ) 7OCH2CH} ( _CH3 )OH.
Such fluoromonols are available as commercial products (manufactured by Archroma, "Fluowet N083", "Fluowet N050", etc.).

The fluorine content of the fluoropolyol is preferably 10 to 50% by mass, more preferably 10 to 45% by mass, and even more preferably 15 to 40% by mass.
Preferably, the fluoropolyol is nonionic.
The hydroxyl value of the fluoropolyol is preferably 10 to 35 mgKOH/g, more preferably 10 to 30 mgKOH/g, even more preferably 10 to 25 mgKOH/g.
The weight average molecular weight of the fluoropolyol is preferably 2,000 to 80,000, more preferably 6,000 to 20,000.
The fluoropolyol is preferably a fluoropolyol containing units based on fluoro(meth)acrylate. Note that "(meth)acrylate" is a general term for acrylate and methacrylate.

The fluoro(meth)acrylate is preferably a monomer represented by the following formula (f).
Formula (f): CH ₂ = CX ^f C(O)O-Q ^f -R ^f
The symbols in the formula have the following meanings.
X ^f represents a hydrogen atom, a chlorine atom, or a methyl group.
Q ^f represents an alkylene group having 1 to 4 carbon atoms or an oxyalkylene group having 2 to 4 carbon atoms.
R ^f represents a polyfluoroalkyl group having 1 to 6 carbon atoms, a polyfluoroalkyl group having 3 to 6 carbon atoms containing an etheric oxygen atom, or a polyfluoroalkenyl group having 4 to 12 carbon atoms, and -CF(CF ₃ )(C(CF(CF ₃ ) ₂ )(=C(CF ₃ ) ₂ )), -C(CF ₃ )=C(CF(CF ₃ ) ₂ ) ₂ , -(CF ₂ ) ₄ F or -( _CF2 ) _6F is preferred.

Specific examples of fluoro(meth)acrylates include _CH2 =CHC(O) _OCH2CH2 ( _CF2 ) _4F , _{CH2 =} C( _CH3 )C(O _{) OCH2CH2} ( _CF2 ) ₄ F, _CH2 =CHC(O) _OCH2CH2 ( _CF2 ) _6F , _CH2 =C( _CH3 )C(O) _OCH2CH2 ( _{CF2 ) 6F} , _CH2 =CHC( _O ) _OCH2CH2OCF ( _CF3 )(C(CF _{( CF3} ) ₂ )(=C( _CF3 ) _{2 )} ), _CH2 =C( _CH3 )C(O) _OCH2CH2OC ( _CF3 )=C(CF( _CF3 ) ₂ ) ₂ , _CH2 =CHC(O)OCH2CH2CH2CH2OCF(CF3 ₎ ( _C (CF( _{CF3 ) 2 )} (=C _{( CF3} ) ₂ )), _{CH2 =} C( _CH3 ) _C (O) _{OCH2CH2CH2CH2OC} ( _CF3 )=C(CF( _CF3 ) _{2 )2 .}

A preferred specific example of the fluoropolyol is a copolymer of a monomer represented by the above formula (f) and a monomer represented by the following formula (o).
Formula (o): CH ₂ = CX ^o C(O)-(OZ ^o ) _mo -OH
The symbols in the formula have the following meanings.
X ^o represents a hydrogen atom or a methyl group.
Z ^o represents an alkylene group having 1 to 4 carbon atoms, and is preferably an ethylene group (-CH ₂ CH ₂ -).
mo is an integer of 1 to 200, preferably an integer of 4 to 30.
Note that Z ^o may be composed of two or more types of groups. In this case, the arrangement of different types of alkylene groups may be random or block-like.
When the compound represented by formula (o) is used, not only the dispersibility of the present dispersion is excellent, but also the physical properties such as wettability and adhesiveness of the molded article are particularly likely to be improved.

Specific examples of _the monomer represented by formula (o) include _{CH2 =} CHCOO( _CH2CH2O ) _8OH , _CH2 =CHCOO( _CH2CH2O ) _10OH , _CH2 =CHCOO( _{CH2 CH2O ) 12 OH , CH2} = _{CHCOOCH2CH2CH2CH2O ( CH2CH2O ) 8 OH , CH2} = _{CHCOOCH2CH2CH2CH2O} ( _{CH2CH2O ) 10OH} , _CH2 = _{CHCOOCH2CH2CH2CH2O} ( _{CH2CH2O ) 12 OH} , _CH2 = _C ( _CH3 )COO( _CH2CH ( _CH3 )O) ₈ OH _{, CH2} =C( _CH3 )COO( _CH2CH ( _CH3 )O) ₁₂ OH, _CH2 =C( _CH3 )COO( _CH2CH ( _CH3 )O) _16OH , _CH2 =C( _CH3 ) _{COOCH2CH 2} CH ₂ CH ₂ O(CH ₂ CH(CH ₃ )O) ₈ OH, CH ₂ =C(CH ₃ )COOCH ₂ CH ₂ CH ₂ CH ₂ O(CH ₂ CH(CH ₃ )O) ₁₂ OH, CH ₂ =C( _CH3 ) _{COOCH2CH2CH2CH2O} ( _CH2CH ( _{CH3 ) O} ) _{16OH .}

The fluoropolyol may consist only of units based on the monomer represented by formula (f) and units based on the monomer represented by formula (o), or may further contain other units. .
The content of units based on the monomer represented by formula (f) relative to all units contained in the fluoropolyol is preferably 60 to 90 mol%, more preferably 70 to 90 mol%.
The content of units based on the monomer represented by formula (o) relative to all units contained in the fluoropolyol is preferably 10 to 40 mol%, more preferably 10 to 30 mol%.
The total content of units based on the monomer represented by formula (f) and the monomer represented by formula (o) with respect to all units contained in the above fluoropolyol is preferably 90 to 100 mol%, and 100 to 100% by mole. Mol% is more preferred.
The proportion of fluoroalcohol in this dispersion is preferably 10% by mass or less, more preferably 1% by mass or less, and even more preferably 0.01% by mass or less. The lower limit of the above ratio is usually more than 0%.

The aqueous medium in the present invention is a dispersion medium of the present dispersion, and has water as a main component.
The aqueous medium may consist of only water, or may consist of water and a water-soluble compound.
However, the water-soluble compound is preferably a compound that is liquid at 25° C., does not react with each polymer, or has extremely poor reactivity, and can be easily removed by heating or the like. Further, the aqueous medium preferably contains 95% by mass or more of water, more preferably 99% by mass or more of water, and even more preferably 100% by mass of water.
The proportion of the aqueous medium in this dispersion is preferably 15 to 65% by mass, more preferably 25 to 50% by mass. Within this range, the coating properties of the present dispersion are excellent, and the resulting molded product is unlikely to have poor appearance.

The dispersion may contain F polymer, non-thermofusible PTFE or M polymer, as well as other materials other than the aqueous medium. Other materials include thixotropic agents, fillers, antifoaming agents, dehydrating agents, plasticizers, weathering agents, antioxidants, heat stabilizers, lubricants, antistatic agents, brighteners, colorants, and conductive agents. , mold release agents, surface treatment agents, viscosity modifiers, and flame retardants. Other materials may or may not be dissolved in the present dispersion.

Other materials include thermosetting resins (epoxy resins, thermosetting polyimide resins, polyimide precursors (polyamic acids), acrylic resins, phenolic resins, resins other than F polymer, non-thermofusible PTFE, or M polymer). , polyester resin, polyolefin resin, modified polyphenylene ether resin, bismaleimide resin, polyfunctional cyanate ester resin, polyfunctional maleimide-cyanate ester resin, polyfunctional maleimide resin, vinyl ester resin, urea resin, diallyl phthalate resin, melanin resin, guanamine resin, melamine-urea cocondensation resin, etc.), heat-melting resin (polyester resin, polyolefin resin, styrene resin, polycarbonate, thermoplastic polyimide, polyarylate, polysulfone, polyallylsulfone, aromatic polyamide, aromatic poly etheramide, polyphenylene sulfide, polyallyl ether ketone, polyamideimide, liquid crystalline polyester, polyphenylene ether, etc.), reactive alkoxysilane, carbon black, inorganic fillers (hollow inorganic microspheres such as glass microspheres, ceramic microspheres, etc.) ).

The viscosity of the present dispersion is preferably 1 to 1000 mPa·s, more preferably 5 to 500 mPa·s, even more preferably 10 to 200 mPa·s.
The thixotropic ratio of this dispersion is preferably 0.8 to 2.2.
In this case, it is easy to balance the dispersibility and coatability of the present dispersion.

This dispersion can be produced by mixing powder (1) and powder (21) or powder (22). Specifically, it is preferable to produce by mixing a dispersion (p1) containing powder (1) and an aqueous medium and a dispersion (p2) containing powder (21) or powder (22) and an aqueous medium. .
The dispersion liquid (p1) and the dispersion liquid (p2) are preferably mixed in a well-dispersed state. For example, if sedimentation of solid content is observed in the dispersion liquid (p1), immediately before mixing, the dispersion liquid (p1) is dispersed using a homodisper, and then further dispersed using a homogenizer to maintain a dispersed state. It is preferable to improve In particular, when using the dispersion liquid (p1) stored at 0 to 40°C, it is preferable to carry out these dispersion treatments.
The aqueous medium (dispersion medium) in the dispersion liquid (p1) and the dispersion liquid (p2) is preferably water.

This dispersion has excellent dispersion stability and storage stability, as well as excellent handling properties. This dispersion liquid can form a molded article exhibiting strong adhesiveness and excellent crack resistance without impairing the physical properties of non-thermofusible PTFE or M polymer.
If this dispersion is applied to the surface of a base material and heated to form a polymer layer containing F polymer and non-thermofusible PTFE or M polymer, a base material layer and a polymer layer composed of the above base material can be formed. It is possible to manufacture a laminate in which these are laminated in this order.
The range of F polymer, powder (1), non-thermofusible PTFE, M polymer, powder (21), powder (22) and aqueous medium in this laminate, including their preferred embodiments, is as follows: Same as definition. Further, the polymer layer may be formed on at least one surface of the base material layer, the polymer layer may be formed on only one surface of the base material layer, or the polymer layer may be formed on both surfaces of the base material layer. .

Application methods on the surface of the base material include spray method, roll coating method, spin coating method, gravure coating method, microgravure coating method, gravure offset method, knife coating method, kiss coating method, bar coating method, die coating method, and fountain coating method. Examples include the Mayer bar method and the slot die coating method.
Formation of the polymer layer may be performed by heating, and it is preferable to heat the base material to a temperature at which the aqueous medium volatilizes (temperature range of 100 to 300°C), and heat the base material to a temperature range at which the aqueous medium volatilizes (temperature range of 100 to 300 °C). It is more preferable to heat the substrate to a temperature range (300 to 400°C) in which the non-thermofusible PTFE is fired.
That is, when the present dispersion containing non-thermo-fusible PTFE is used, the polymer layer preferably contains F polymer and is a polymer layer in which the non-thermo-fusible PTFE is subjected to baking treatment. In this case, the non-thermofusible PTFE may be partially or completely fired.
Further, when the present dispersion containing the M polymer is used, the polymer layer preferably contains the F polymer and is a polymer layer obtained by melt-processing the M polymer. In this case, the M polymer may be partially or completely melt processed.

Examples of the method for heating the substrate include a method using an oven, a method using a ventilation drying oven, and a method of irradiating with heat rays (infrared rays).
The atmosphere for heating the base material may be either normal pressure or reduced pressure. The atmosphere during the holding may be an oxidizing gas (oxygen gas, etc.), a reducing gas (hydrogen gas, etc.), or an inert gas atmosphere (helium gas, neon gas, argon gas, nitrogen gas, etc.). There may be.
The heating time for the base material is usually 0.5 to 30 minutes.
The thickness of the polymer layer is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 10 μm or less. The thickness of the polymer layer is preferably 0.1 μm or more, particularly preferably 4 μm or more. Within this range, a polymer layer with excellent crack resistance can be easily formed without impairing the physical properties of the non-thermofusible PTFE or M polymer.

In the laminate, the base material layer and the polymer layer are firmly adhered to each other. The peel strength between the base material layer and the polymer layer is preferably 10 N/cm or more, particularly preferably 15 N/cm or more. The upper limit of the peel strength is usually 100 N/cm.
The material of the base material may be any of metals such as copper, aluminum, iron, nickel, zinc, and alloys thereof, glass, resin, silicon, and ceramics.
The shape of the base material may be planar, curved, or uneven, and may be foil, plate, film, or fibrous.
A specific example of the laminate is a metal foil with a polymer layer, in which the base material is a metal foil and has a metal foil layer made of the metal foil and a polymer layer in this order. A separate adhesive layer may be provided between the metal foil layer and the polymer layer, but since the polymer layer has excellent adhesive properties, the adhesive layer may not be provided.

Suitable embodiments of the metal foil include copper foils such as rolled copper foil and electrolytic copper foil. In the laminate, the thickness of the metal foil is preferably 3 to 18 μm, and the thickness of the polymer layer is preferably 1 to 50 μm.
If a pattern circuit is formed on the copper foil layer, the laminate can be used as a printed wiring board with the polymer layer as an electrical insulating layer.

Specific examples of the laminate include a laminate film in which the base material is a polyimide film and has a polymer layer formed from the present dispersion on at least one surface of a polyimide layer composed of the polyimide film; A specific example is a laminated film having polymer layers formed from the present dispersion on both sides of a polyimide layer.
A separate adhesive layer may be provided between the polyimide layer and the polymer layer, but since the polymer layer formed from the present dispersion has excellent adhesive properties, the adhesive layer may not be provided.

A preferred embodiment of the polyimide film includes 2,2',3,3'- or 3,3',4,4'-biphenyltetracarboxylic dianhydride (3,3',4,4'-benzophenonetetra A polymer film of a component whose main component is carboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, etc.) and a component whose main component is paraphenylenediamine. Can be mentioned. A specific example of the polyimide film is Apical Type AF (manufactured by Kaneka North America).
Such polyimide films are useful as insulating coatings. Its basis weight is preferably 23.5 g/m ² or less, and its loop stiffness value is preferably 0.45 g/cm or more.
The thickness of the polymer layer in such a laminated film is preferably 1 to 200 μm, more preferably 5 to 20 μm. Further, the thickness of the polyimide layer (polyimide film) is preferably 5 to 150 μm.

Such laminated films have excellent electrical insulation properties, abrasion resistance, hydrolysis resistance, etc., and can be used as electrical insulating tapes and wrapping materials for electrical cables or electrical wires, such as electrical wires for aerospace or electric vehicles. It can be used particularly preferably as a material or cable material.

Since the laminate of the present invention has a polymer layer containing F polymer and having excellent adhesive properties, a composite laminate can also be produced by further laminating other materials on the polymer layer of the laminate.
If the surface of the polymer layer of the laminate and the second base material are pressed together, the resultant layer will be composed of the first base material layer (original base material layer of the laminate), the polymer layer, and the second base material. A composite laminate is obtained in which the second base material layer and the second base material layer are laminated in this order.

The material of the second base material may be any of metals such as copper, aluminum, iron, nickel, zinc, and alloys thereof, glass, resin, silicon, and ceramics.
The shape of the second base material is also not particularly limited, and may be planar, curved, or uneven, and may be foil, plate, film, or fibrous.
Specific examples of the second base material include a heat-resistant resin base material, a prepreg that is a precursor of a fiber-reinforced resin board, and the like.
Prepreg is a sheet-like base material made by impregnating a base material (tow, woven fabric, etc.) of reinforcing fibers (glass fiber, carbon fiber, etc.) with resin (thermosetting resin, thermoplastic resin, etc. mentioned above). .
The heat-resistant resin base material is preferably a film containing a heat-resistant resin, and may have a single layer or a multilayer structure.
Examples of the heat-resistant resin include polyimide, polyarylate, polysulfone, polyallylsulfone, aromatic polyamide, aromatic polyetheramide, polyphenylene sulfide, polyallyletherketone, polyamideimide, liquid crystalline polyester, PTFE, and the like.

A thermocompression bonding method can be mentioned as a method for pressure-bonding the surface of the polymer layer of the laminate and the second base material.
When the second base material is a prepreg, the compression temperature is preferably 160 to 220°C.
When the second base material is a heat-resistant resin base material, the compression temperature is preferably 300 to 400°C.
The thermocompression bonding is preferably carried out under a reduced pressure atmosphere, and particularly preferably carried out at a degree of vacuum of 20 kPa or less. Within this range, it is possible to suppress the inclusion of air bubbles at each interface in the composite laminate, and to suppress deterioration due to oxidation. Further, in thermocompression bonding, it is preferable to raise the temperature after reaching the above degree of vacuum.
The pressure in thermocompression bonding is preferably 0.2 to 10 MPa.

When a liquid layer forming material for forming a second polymer layer is applied to the surface of the polymer layer of the laminate to form the second polymer layer, the first base layer, the polymer layer, and the second polymer layer are formed. A composite laminate is obtained in which these polymer layers are laminated in this order.
The liquid layer-forming material is not particularly limited, and the present dispersion may be used.
The method of forming the second polymer layer is also not particularly limited, and can be appropriately determined depending on the properties of the liquid layer-forming material used. For example, when the layer forming material is the present dispersion, the second polymer layer can be formed according to the same conditions as the method for forming the polymer layer in the laminate. In other words, if the layer-forming material is the present dispersion, the polymer layer can be multilayered to easily form a thicker polymer layer.

A specific example of a composite laminate obtained by such a manufacturing method includes a composite laminate obtained by using the present dispersion liquid or a dispersion liquid containing the F polymer as a liquid layer forming material. Since the second polymer layer is formed on the polymer layer exhibiting strong adhesion, a composite laminate with high peel strength can be obtained even when the latter dispersion is used.
According to the laminate of the present invention, it can be said that a polymer layer with excellent crack resistance is formed without impairing the physical properties of each polymer. By removing the base material layer from the laminate, a polymer film homogeneously containing each polymer can be obtained.
In the polymer film containing non-thermo-fusible PTFE, it is preferable that the non-thermo-fusible PTFE containing F polymer is subjected to firing treatment. In this case, the non-thermofusible PTFE may be partially or completely fired.
In the polymer film containing the M polymer, it is preferable that the M polymer containing the F polymer is subjected to a firing treatment. In this case, the M polymer may be partially or completely baked.

Examples of methods for removing the base material layer from the laminate include a method of peeling and removing the base material layer from the laminate, and a method of dissolving and removing the base material layer from the laminate. For example, if the base layer is made of copper foil, if the surface of the laminate on the base layer side is brought into contact with an etching solution such as hydrochloric acid, the base layer will be dissolved and removed, and the polymer layer will be removed. Single polymer membranes can be easily obtained.
The range of polymers in the polymer film, including their preferred embodiments, is the same as defined in the present dispersion.
The thickness of the polymer film is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 10 μm or less. The thickness of the polymer film is preferably 1 μm or more, more preferably 4 μm or more. In this range, the polymer film has better adhesion and crack resistance without impairing the physical properties of each polymer.

By impregnating a woven fabric with this dispersion and drying the woven fabric, a coated woven fabric, which is a woven fabric covered with a polymer layer, can be obtained.
The woven fabric is a heat-resistant woven fabric that can withstand drying, 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. From the viewpoint of insulation, a plain weave glass fiber woven fabric made of electrically insulating E-glass yarn defined in JIS R 3410:2006 is more preferable. The woven fabric may be treated with a silane coupling agent from the viewpoint of improving close adhesion to the polymer layer.
The total content of F polymer and non-thermofusible PTFE or M polymer in the covering fabric is preferably 30 to 80% by mass.

Examples of methods for impregnating a woven fabric with the present dispersion include a method of immersing the woven fabric in the present dispersion and a method of applying the present dispersion to the woven fabric. The number of times of dipping in the former method and the number of times of application in the latter method may be one, two or more, respectively. Since this dispersion containing F polymer, which has excellent adhesion to other materials, is used, a covered woven fabric with a high polymer content, in which the woven fabric and the polymer are firmly bonded, can be obtained even after at least the number of dippings or coatings. It will be done.
The method for drying the woven fabric can be determined as appropriate depending on the type of aqueous medium contained in the present dispersion. For example, when the aqueous medium consists only of water, the woven fabric is dried with ventilation in an atmosphere of 80 to 120°C. One method is to pass it through a furnace.
When drying the woven fabric, the polymer may be fired. The method of firing the polymer can be appropriately determined depending on the type of each polymer, and for example, a method of passing the woven fabric through a ventilation drying oven in an atmosphere of 300 to 400° C. can be mentioned. Note that drying the woven fabric and firing the polymer may be performed in one step.

The resulting covered woven fabric has excellent properties such as high adhesion between the polymer layer and the woven fabric, high surface smoothness, and little distortion because the polymer layer contains the F polymer. A laminate obtained by thermocompression bonding such a covering fabric and metal foil has high peel strength and is resistant to warping, so it can be suitably used as a printed circuit board material.
Alternatively, the dispersion containing the woven fabric may be applied to the surface of the base material and dried by heating to form a covering woven fabric layer containing the F polymer and non-thermofusible PTFE or the M polymer and the woven fabric. good. Thereby, it is possible to manufacture a laminate in which a base material layer made of the above-mentioned base material and a covering fabric layer are laminated in this order. The mode is not particularly limited, and if the present dispersion containing woven fabric is applied to a part of the inner wall surface of a molded product such as a tank, piping, or container, and heated while rotating the molded product, the inner wall of the molded product can be heated. A covering fabric layer can be formed on the entire surface. The method for producing a covered woven fabric of the present invention is also useful as a method for lining the inner wall surface of molded products such as tanks, piping, and containers.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples, but the present invention is not limited thereto.
Various measurement methods are shown below.
<D50 and D90 of powder>
The powder was dispersed in water and measured using a laser diffraction/scattering particle size distribution measuring device (manufactured by Horiba, Ltd., "LA-920 measuring device").
<Storage stability of powder dispersion>
After the powder dispersion was left at 25° C. for one week, the condition was visually confirmed and evaluated using the following evaluation criteria.
○: Sediment is not confirmed.
△: Sediment is observed, but it redisperses when shaken by hand.
×: Sediment is confirmed and cannot be redispersed by shaking by hand.

<Crack resistance of polymer layer>
Apply the powder dispersion liquid to the surface of a stainless steel plate (thickness: 0.5 mm) with vinyl tape pasted on one end, smooth it by sliding a rod along the end, and then heat it at 100°C for 3 minutes. It was dried three times and further heated at 340°C for 10 minutes. As a result, a polymer layer having a sloped thickness was formed on the surface of the stainless steel plate due to the thickness of the vinyl tape attached to the edge. This stainless steel plate was visually confirmed, and the thickness of the polymer layer at the tip of the crack line generation part (the thinnest part of the polymer layer) was measured using MINITEST 3000 (manufactured by Electro Physik), and evaluated according to the following evaluation criteria. evaluated.
Good: The thickness of the polymer layer at the tip where cracks occur is 10 μm or more.
Δ: The thickness of the polymer layer at the tip where cracks occur is 5 μm or more and less than 10 μm.
×: The thickness of the polymer layer at the tip where cracks occur is less than 5 μm.

<Peel strength of laminate>
A laminate cut out into a rectangular shape (length: 100 mm, width: 10 mm) was fixed at a position 50 mm from one end in the longitudinal direction, and pulled at a pulling speed of 50 mm/min, at an angle of 90° to the laminate from one end in the longitudinal direction. The maximum load applied when the metal foil layer and polymer layer were peeled off was measured as peel strength (N/cm), and evaluated using the following evaluation criteria.
○: Peel strength is 10 N/cm or more.
×: Peel strength is less than 10 N/cm.

The materials used are shown below.
[Polymer and its powder]
F Polymer 1: Copolymer containing 97.9 mol%, 0.1 mol%, 2.0 mol% of units based on TFE, units based on NAH, and units based on PPVE (melting point: 300 ° C.)
Polymer A1: A copolymer without oxygen-containing polar groups (melting point: 305° C.) containing, in this order, 98.0 mol % and 2.0 mol % of units based on TFE and units based on PPVE.
P polymer 1: Non-thermofusible PTFE with fibrillarity, containing 99.9 mol% or more of TFE-based units (standard specific gravity: 2.18, melt viscosity at 380°C: 3.0 × 10 ⁹ Pa・s)
M polymer 1: Hot-melt modified PTFE containing 99.5 mol% or more of TFE-based units and a trace amount of PFBE-based units (melt viscosity at 380°C: 1 x 10 ⁶ Pa s)

F Powder 11: F Polymer 1 powder (D50: 1.7 μm, D90: 3.8 μm)
F Powder 12: Powder of F Polymer 1 (D50: 0.3 μm, D90: 1.8 μm) [This F Powder 12 was obtained by subjecting F Powder 11 to a wet jet mill. ]
Powder A1: Polymer A1 powder (D50: 0.3 μm, D90: 1.5 μm)
P Powder 1: Powder of P Polymer 1 (D50: 0.3 μm) [This P Powder 1 is available as an aqueous dispersion of P Powder 1. ]
M Powder 1: Powder of M Polymer 1 (D50: 0.3 μm) [This M Powder 1 is available as an aqueous dispersion of M Powder 1. ]

[Dispersant]
FM1:F( _CF2 ) _6CH2 ( _OCH2CH2 ) _7OCH2CH ( _CH3 )OH ( _fluorine content: 34% _by mass, hydroxyl value _: 78mgKOH/g)
FP1: Unit based on _CH2 =C( _CH3 )C ₍ O) _OCH2CH2 ( _CF2 ) _6F and based on _CH2 =C( _CH3 )C( _O )( _OCH2CH2 ) _23OH Copolymer containing units (fluorine content: 35% by mass, hydroxyl value: 19mgKOH/g)

[Example 1] Production example of powder dispersion [Example 1-1] Production example of dispersion 1 A dispersion containing 30 parts by mass of F powder 12, 5 parts by mass of FM1 and 65 parts by mass of water, and P powder 1 and an aqueous dispersion containing 50% by mass. As a result, each powder is dispersed in water, and powder dispersion 1 (F polymer 1 content/content of P polymer 1: 0.11).
[Example 1-2 to Example 1-9] Production example of powder dispersions 2 to 9 Powder dispersions 2 to 9 were prepared in the same manner as in Example 1-1, except that the type of powder and the type of dispersant were changed. I got it. The types of powder dispersions and the evaluation results of their storage stability are summarized in Table 1 below.

[Example 2] Example of manufacturing a laminate [Example 2-1] Example of manufacturing a laminate 1 Powder dispersion 1 was applied to the surface of copper foil, dried at 100°C for 10 minutes, and dried at 340°C under an inert gas atmosphere. After baking for 10 minutes, the mixture was slowly cooled. As a result, a laminate (with a polymer layer Copper foil) 1 was obtained.
[Example 2-2 to Examples 2 to 9] Production examples of laminates 2 to 9 Laminates 2 to 9 were produced in the same manner as in Example 2-1, except that the type of powder dispersion was changed.
The crack resistance evaluation results of Powder Dispersions 1 to 4 and 9 and the peel strength evaluation results of Laminated Products 1 to 9 are summarized in Table 2 below.

[Example 3] Production example of polymer film [Example 3-1] Production example of polymer film 3 Powder dispersion 3 was applied to the surface of copper foil, dried at 100°C for 10 minutes, and dried at 340°C under an inert gas atmosphere. After baking for 10 minutes, the mixture was slowly cooled. Thereby, a laminate having a copper foil layer made of copper foil and a polymer layer containing P polymer 1 and F polymer 1 formed on the surface of the copper foil layer was obtained. The operations of applying the powder dispersion 3 to the surface of the polymer layer of this laminate, drying, and baking were repeated under the same conditions. This increased the thickness of the polymer layer to 30 μm. Thereafter, the copper foil layer of the laminate was removed with hydrochloric acid to obtain a polymer film 3 containing P polymer 1 and F polymer 1.
[Example 3-2] Manufacturing example of polymer film 4 and polymer films 7 to 9 Polymer film 4 was produced from powder dispersion 4 in the same manner as Example 3-1 except that the type of powder dispersion was changed. A polymer film 7 was obtained from the liquid 7, a polymer film 8 was obtained from the powder dispersion 8, and a polymer film 9 was obtained from the powder dispersion 9.

Polymer membrane 3, polymer membrane 4, and polymer membrane 9 are all porous membranes, and when subjected to stretching treatment, the breaking strength of polymer membrane 3, polymer membrane 4, and polymer membrane 9 was in descending order of strength. .
Further, the polymer membrane was subjected to stretching treatment (stretching ratio: 200%) to obtain a stretched membrane 3 from the polymer membrane 3, a stretched membrane 4 from the polymer membrane 4, and a stretched membrane 9 from the polymer membrane 9, respectively. Each stretched membrane is a porous membrane, and when comparing the open pore states, the pore size distribution is in descending order of Stretched membrane 3, Stretched membrane 4, and Stretched membrane 9. was forming.
When polymer film 7, polymer film 8, and polymer film 9 were subjected to stretching treatment, the breaking strength of polymer film 7, polymer film 8, and polymer film 9 was determined in descending order of strength. Moreover, as a result of subjecting each thin film to a repeated bending test, the number of times the thin film was cut was polymer film 7, polymer film 8, and polymer film 9 in descending order.

[Example 4] Example of manufacturing a polymer membrane (Part 2)
A dispersion containing 30 parts by mass of F Powder 12, 5 parts by mass of FM1, and 65 parts by mass of water, an aqueous dispersion containing 50 mass% of M Powder 1, and an aqueous dispersion containing 50 mass% of P Powder 1. mixed with. As a result, each powder is dispersed in water, and 10% by mass of M polymer 1, 10% by mass of F polymer 1, and 10% by mass of P polymer 1 are added to the total of M polymer 1, F polymer 1, and P polymer 1. A powder dispersion containing 80% by mass (content of F polymer 1/content of M polymer 1: 1.0) was obtained.
This powder dispersion was applied to the surface of a copper foil, dried at 100°C for 10 minutes, baked at 340°C for 10 minutes in an inert gas atmosphere, and then slowly cooled. Thereby, a laminate having a copper foil layer made of copper foil and a polymer layer formed on the surface of the copper foil layer was obtained. The operations of applying the powder dispersion to the surface of the polymer layer of this laminate, drying, and baking were repeated under the same conditions. This increased the thickness of the polymer layer to 30 μm. Thereafter, the copper foil layer of the laminate was removed with hydrochloric acid to obtain a polymer film containing M polymer 1, F polymer 1, and P polymer 1. When this polymer membrane was subjected to stretching treatment (stretching rate: 200%), a dense porous membrane with a small pore size distribution was obtained.

This dispersion can be used to manufacture molded products such as films, impregnated materials (prepreg, etc.), laminates (metal laminates such as resin-coated copper foil, etc.), and has excellent mold releasability, electrical properties, water and oil repellency, and It can be used to manufacture molded products for applications that require chemical resistance, weather resistance, heat resistance, slipperiness, abrasion resistance, etc. Molded products obtained from this dispersion are useful as antenna parts, printed circuit boards, aircraft parts, automobile parts, sports equipment, food industry products, paints, cosmetics, etc. Specifically, they are useful as wire coating materials (aircraft electric wires, etc.), electrical insulating tapes, insulating tapes for oil drilling, materials for printed circuit boards, 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, etc., sliding members (load bearings, sliding shafts, valves, bearings, gears, cams, belt conveyors) , food conveyance belts, etc.), tools (shovels, files, chisels, saws, etc.), boilers, hoppers, pipes, ovens, baking molds, chutes, dies, toilet bowls, and container coatings.

Claims (14)

The following powder dispersion is applied to the surface of a base material, the aqueous medium is removed by heating to form a polymer layer, and the base material layer composed of the base material and the polymer layer are laminated in this order. A method for producing a polymer film, comprising: obtaining a laminate, and removing the base material layer from the laminate to obtain a polymer film constituted by the polymer layer.
Powder dispersion: Powder of fluoropolymer having units based on tetrafluoroethylene and oxygen-containing polar groups (1) and powder of non-thermofusible polytetrafluoroethylene (21) or powder of thermofusible fluoropolymer (22) and an aqueous medium , and the ratio by mass of the content of the fluoropolymer to the content of the non-heat-melting polytetrafluoroethylene or the content of the heat-melting fluoropolymer is 0.4 or less. A powder dispersion. In the powder dispersion, the volume-based cumulative 50% diameter of the powder (1) is 0.01 to 75 μm, and the volume-based cumulative 50% diameter of the powder (21) or the powder (22) is 0.01 to 75 μm. The manufacturing method according to claim 1, wherein the thickness is 01 to 100 μm. The manufacturing method according to claim 1 or 2 , wherein the fluoropolymer has a melting temperature of 140 to 320°C. The manufacturing method according to any one of claims 1 to 3 , wherein the oxygen-containing polar group is a hydroxyl group-containing group or a carbonyl group-containing group. The manufacturing method according to any one of claims 1 to 4 , wherein the non-thermofusible polytetrafluoroethylene has fibrillar properties. 6. The heat-melting fluoropolymer is a modified polytetrafluoroethylene, a copolymer of tetrafluoroethylene and perfluoro(alkyl vinyl ether), or a copolymer of tetrafluoroethylene and hexafluoropropylene . The manufacturing method described in. The manufacturing method according to any one of claims 1 to 6 , comprising both the non-thermofusible polytetrafluoroethylene powder (21) and the thermofusible fluoropolymer powder (22). A method for producing a coated woven fabric, which comprises impregnating a woven fabric with the following powder dispersion and drying the woven fabric to obtain a woven fabric coated with a polymer layer.
Powder dispersion: Powder of fluoropolymer having units based on tetrafluoroethylene and oxygen-containing polar groups (1) and powder of non-thermofusible polytetrafluoroethylene (21) or powder of thermofusible fluoropolymer (22) and an aqueous medium, and the ratio by mass of the content of the fluoropolymer to the content of the non-heat-melting polytetrafluoroethylene or the content of the heat-melting fluoropolymer is 0.4 or less. , powder dispersion. In the powder dispersion, the volume-based cumulative 50% diameter of the powder (1) is 0.01 to 75 μm, and the volume-based cumulative 50% diameter of the powder (21) or the powder (22) is 0.01 to 75 μm. The manufacturing method according to claim 8, wherein the thickness is 01 to 100 μm. The manufacturing method according to claim 8 or 9, wherein the fluoropolymer has a melting temperature of 140 to 320°C. The manufacturing method according to any one of claims 8 to 10, wherein the oxygen-containing polar group is a hydroxyl group-containing group or a carbonyl group-containing group. The manufacturing method according to any one of claims 8 to 11, wherein the non-thermofusible polytetrafluoroethylene has fibrillar properties. 13. The heat-melting fluoropolymer is a modified polytetrafluoroethylene, a copolymer of tetrafluoroethylene and perfluoro(alkyl vinyl ether), or a copolymer of tetrafluoroethylene and hexafluoropropylene. The manufacturing method described in. The manufacturing method according to any one of claims 8 to 13, comprising both the non-thermofusible polytetrafluoroethylene powder (21) and the thermofusible fluoropolymer powder (22).