JPWO2020050178A1 - Dispersion liquid manufacturing method - Google Patents

Abstract

Provided is a dispersion liquid having excellent dispersion stability of particles even in a high temperature environment or when the content of particles is high. The method for producing a dispersion liquid of the present invention comprises coarse particles of a fluoroolefin polymer having a melt viscosity at 380 ° C. of 1 × 102 to 1 × 1010 Pa · s, a dispersant having a cloud point of more than 50 ° C., and a liquid dispersion medium. A liquid composition having a viscosity of 10000 mPa · s or less containing A dispersion liquid containing the agent and the fine particles dispersed in the liquid dispersion medium is obtained.

Description

The present invention relates to a method for producing a dispersion liquid in which fine particles of a fluoroolefin polymer are dispersed in a liquid dispersion medium.

When the dispersion liquid in which the particles of the fluoroolefin polymer are dispersed in the liquid dispersion medium is applied to the surface of various base materials, the physical properties based on the fluoroolefin polymer can be imparted to the surface thereof, which is useful as a coating agent.
As a method for producing such a dispersion liquid, a method of subjecting a dispersion liquid in which particles of a fluoroolefin polymer are dispersed to a wet jet mill method is known (see Patent Documents 1 and 2).

Patent Document 1 discloses a method for producing a dispersion liquid in which particles of PFA having a hydroxy group are dispersed in water and subjected to a wet jet mill method to make the particles finely divided. Further, Patent Document 2 describes a method in which a dispersion liquid in which PTFE particles and carbon nanotubes are dispersed in a non-aqueous dispersion medium is subjected to a wet jet mill method to obtain a composite in which carbon nanotubes are trapped in fibrillated PTFE. Is disclosed.

Japanese Unexamined Patent Publication No. 2008-260864 International Publication No. 2017/022229

Fluoroolefin-based polymers have essentially low surface tension and low interaction with other materials. Therefore, in a liquid composition containing particles of a fluoroolefin polymer, the dispersibility of the particles is unstable. The properties (viscosity, color tone, phase state, etc.) of such a liquid composition are likely to change not only by internal factors such as the content ratio of each component but also by external factors such as temperature and external force. Therefore, when the liquid composition is applied to the wet jet mill method in which a large external factor is locally applied, alteration of each component in the liquid composition or change of interaction between the components occurs.

Therefore, the particles of the fluoroolefin polymer or even the alteration of the fluoroolefin polymer itself may be attracted, and a desired dispersion liquid may not be obtained. The present inventors have specifically found a problem that a dispersion liquid having excellent particle dispersion stability cannot be obtained in a high temperature environment or when the particle content is high.

As a result of diligent studies, the present inventors mixed a dispersant with a fluoroolefin polymer having a predetermined melt viscosity, and when a liquid composition having a predetermined viscosity was pressure-flowed in a flow path, it was subjected to a high temperature environment. It was also found that a dispersion liquid having excellent particle dispersion stability can be obtained even when the particle content is high.
The present invention has the following aspects.

[1] Viscosity containing coarse particles of a fluoroolefin polymer having a melt viscosity at 380 ° C. of 1 × 10 ² to 1 × 10 ¹⁰ Pa · s, a dispersant having a cloud point of more than 50 ° C., and a liquid dispersion medium. A liquid composition of 10,000 mPa · s or less is pressure-circulated in the flow path, and the coarse particles are pulverized into fine particles having an average particle size smaller than the average particle size of the coarse particles, and the dispersant and the liquid dispersion medium are used. A method for producing a dispersion liquid, which obtains a dispersion liquid containing the dispersed fine particles.
[2] The production method according to [1], wherein the melting temperature of the fluoroolefin polymer is 200 ° C. or higher.
[3] The production method according to [1] or [2], wherein the dispersant is a fluorine-based dispersant.
[4] The production method according to [3], wherein the fluorine-based dispersant is at least one compound selected from the group consisting of fluoromonool, fluoropolyol, fluorosilicone and fluoropolyether.
[5] The production method according to [3] or [4], wherein the fluorine content of the fluorine-based dispersant is 10 to 50% by mass.

[6] Any of [1] to [5], wherein the dispersant is at least one compound selected from the group consisting of fluoromonool and fluoropolyol, and has a hydroxyl value of 10 to 100 mgKOH / g. The manufacturing method described in Crab.
[7] The production method according to any one of claims [1] to [6], wherein the dispersant is fluoromonool and the liquid dispersion medium is an aqueous dispersion medium.
[8] The production method according to any one of [1] to [6], wherein the dispersant is a fluoropolyol and the liquid dispersion medium is a non-aqueous dispersion medium.
[9] The production method according to any one of [1] to [8], wherein the average particle size of the fine particles is 1 μm or less.
[10] The production method according to any one of [1] to [9], wherein the average particle size of the coarse particles is more than 1 μm and less than 10 μm.

[11] The production method according to any one of [1] to [10], wherein the liquid composition contains 1 part by mass or more of the dispersant with respect to 100 parts by mass of the coarse particles.
[12] The production method according to any one of [1] to [11], wherein the liquid composition contains 1 to 50% by mass of the coarse particles.
[13] The production method according to any one of [1] to [12], wherein the liquid composition is circulated and circulated in the flow path.
[14] The liquid composition is circulated and circulated in the flow path under the condition that the value obtained by dividing the product of the flow rate of the flow path and the circulation time by the total amount of the liquid composition is more than 10. The production method according to any one of [13].
[15] The production method according to any one of [1] to [14], wherein the average particle size of the fine particles is 0.5 μm or less, and the volume-based cumulative 90% diameter of the fine particles is 2 μm or less.

According to the present invention, a dispersion liquid having excellent particle dispersion stability can be obtained even in a high temperature environment or when the particle content is high.

The following terms have the following meanings.
The "average particle size (D50)" is a volume-based cumulative 50% diameter of particles determined by a laser diffraction / scattering method. That is, the particle size distribution is measured by a laser diffraction / scattering method, the cumulative curve is obtained with the total volume of the particle population as 100%, and the particle size is the point at which the cumulative volume is 50% on the cumulative curve.
“Particle D90” is the volume-based cumulative 90% diameter of the particles, which is obtained in the same manner as the above D50.
The "melt viscosity of the polymer" is based on ASTM D 1238, and a polymer sample (2 g) that has been preheated at the measurement temperature for 5 minutes using a flow tester and a 2Φ-8L die is loaded with 0.7 MPa. It is a value measured by holding it at the measurement temperature at.
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.
The "viscosity of the liquid composition" is a value measured using a B-type viscometer at room temperature (25 ° C.) under the condition of a rotation speed of 30 rpm. The measurement is repeated 3 times, and the average value of the measured values for 3 times is used.
The "unit" in the polymer may be an atomic group formed directly from the monomer by the polymerization reaction, and the polymer obtained by the polymerization reaction is treated by a predetermined method to convert a part of the structure. May be.

The production method of the present invention has 50 coarse particles and 50 cloud points of a fluoroolefin polymer (hereinafter, also referred to as “F polymer”) having a melt viscosity at 380 ° C. of 1 × 10 ² to 1 × 10 ^{10 Pa · s.} A liquid composition having a viscosity of 10,000 mPa · s or less, which is a mixture of a dispersant exceeding ° C. and a liquid dispersion medium, is pressure-flowed through a flow path (hereinafter, also referred to as “subject to a wet jet mill method”), and is coarse. The present invention relates to a method of pulverizing particles into fine particles having a smaller average particle size and obtaining a dispersion liquid in which the fine particles are dispersed in a liquid dispersion medium by the action of a dispersant.
The dispersion liquid obtained by the production method of the present invention is excellent in dispersion stability of fine particles even in a high temperature environment or when the content of fine particles is high, and is also excellent in compatibility with other materials. The reason for this is not always clear, but it can be considered as follows.

It is considered that the pulverization of particles in the wet jet mill method occurs when the particles collide with the flow path wall or the particles collide with each other in the flow path. The present inventors tend to induce the alteration of the F polymer in or near the flow path by the thermal energy at the time of this collision, and reduce the physical properties (dispersion stability, viscosity, etc.) of the obtained dispersion liquid. I found a point. Then, by adjusting the viscosity of the liquid composition to be subjected to the wet jet mill method, the melt viscosity of the F polymer contained therein, and the cloud point of the dispersant contained therein, the state of the particles of the F polymer is highly stabilized. It was found that a dispersion liquid having excellent dispersibility can be obtained by suppressing such deterioration of physical properties.

The F polymer in the present invention is a polymer containing a unit based on a fluoroolefin, and may be a homopolymer or a copolymer.
The F polymer is a homopolymer composed of units based on tetrafluoroethylene (hereinafter, also referred to as “TFE unit”), a polymer containing a unit based on vinylidene fluoride (VDF), or a TFE unit and perfluoro (alkyl vinyl ether). A group consisting of units (hereinafter, also referred to as "PAVE units"), hexafluoropropylene-based units (hereinafter, also referred to as "HFP units"), and fluoroalkylethylene-based units (hereinafter, also referred to as "FAE units"). Copolymers containing at least one homopolymer-based unit selected from are preferred.

Here, the homopolymer composed of TFE units also includes polymers containing a very small amount of units other than TFE units. In the polymer, the ratio of TFE units to all the units contained in the polymer is preferably 99.9 mol% or more.
For example, if the insulating resin layer of the printed wiring board used for transmitting a high frequency signal is formed by the dispersion liquid obtained in the present invention, the transmission characteristics of the printed wiring board can be improved.
The F polymer is a copolymer of TFE units and PAVE units (hereinafter, also referred to as “PFA”) or TFE units and HFP units from the viewpoint of excellent electrical properties (relative permittivity, dielectric loss tangent) and heat resistance. Copolymers (hereinafter, also referred to as "FEP") are preferable, and PFA is more preferable.

The F polymer is preferably a polymer having at least one functional group selected from the group consisting of a carbonyl group-containing group, a hydroxy group, an epoxy group, an oxetanyl group, an amino group, a nitrile group and an isocyanate group. If the F polymer has the above functional groups, for example, when the insulating resin layer of the printed wiring board is formed from the dispersion obtained in the present invention, the metal wiring (metal foil) of the printed wiring board of the insulating resin layer. Adhesion to is improved. The functional group may be introduced into the F polymer by plasma treatment or the like.
Such a functional group may be contained in the unit constituting the F polymer, or may be contained in the terminal group of the main chain of the polymer. Examples of the latter polymer include polymers having a functional group as a terminal group derived from a polymerization initiator, a chain transfer agent, or the like.

The F polymer is preferably a polymer containing a unit having a functional group and a TFE unit. The polymer preferably contains yet other units.
When the insulating resin layer of the printed wiring board is formed from the dispersion obtained in the present invention, a carbonyl group-containing group is used as the functional group from the viewpoint of further improving the adhesion between the insulating resin layer and the metal wiring in the printed wiring board. preferable.
Examples of the carbonyl group-containing group include a carbonate group, a carboxy group, a haloformyl group, an alkoxycarbonyl group, an acid anhydride residue and a fatty acid residue, and a carboxy group or an acid anhydride residue is preferable.
The monomer having a carbonyl group-containing group is preferably a cyclic monomer having an acid anhydride residue or a monomer having a carboxy group, more preferably a cyclic monomer having an acid anhydride residue, and itaconic anhydride, citraconic anhydride, 5-. Norbornen-2,3-dicarboxylic acid anhydride (also known as hymic anhydride; hereinafter also referred to as "NAH") or maleic anhydride is particularly preferable.

As the unit having a functional group and the unit other than the TFE unit, an HFP unit, a PAVE unit or a FAE unit is preferable.
As PAVE, CF ₂ = CFOCF ₃ , CF ₂ = CFOCF ₂ CF ₃ , CF ₂ = CFOCF ₂ CF ₂ CF ₃ (hereinafter, also referred to as “PPVE”), CF ₂ = CFOCF ₂ CF ₂ CF ₂ CF ₃ , CF ₂ = CFO (CF ₂ ) ₈ F, with PVE being preferred.
As FAE, CH ₂ = CH (CF ₂ ) ₂ F, CH ₂ = CH (CF ₂ ) ₃ F, CH ₂ = CH (CF ₂ ) ₄ F, CH ₂ = CF (CF ₂ ) ₃ H, CH ₂ = CF (CF ₂ ) ₄ H is mentioned, and CH ₂ = CH (CF ₂ ) ₄ F or CH ₂ = CH (CF ₂ ) ₂ F is preferable.

As the F polymer, a polymer containing a unit having a functional group, a TFE unit, a PAVE unit or an HFP unit is preferable. Specific examples of such polymers include the polymers described in WO 2018/16644.
In this case, the ratios of the TFE unit, the PAVE unit, and the unit having a functional group to all the units contained in the F polymer are 90 to 99 mol%, 0.5 to 9.97 mol%, and 0 in this order. .01-3 mol% is preferable.

The melt viscosity of the F polymer in the present invention at 380 ° C. is 1 × 10 ² to 1 × 10 ¹⁰ Pa · s, ^{preferably 1 × 10 3} to 1 × 10 ⁹ Pa · s, and 1 × 10 ⁴ It is particularly preferably ~ 1 × 10 ^{8 Pa · s.} The coarse particles of the F polymer having such a melt viscosity are pulverized into fine particles without being fibrillated.
The coarse particles in the present invention may contain components other than the F polymer, but it is preferable that the F polymer is the main component. The amount of the F polymer contained in the coarse particles (substantially the same for the fine particles after micronization) is preferably 80% by mass or more, more preferably 100% by mass.

The melting temperature of the F polymer is preferably 200 ° C. or higher, more preferably 250 to 380 ° C., and even more preferably 300 to 350 ° C. In this case, when the liquid composition is subjected to the wet jet mill method, it is prevented that the coarse particles are melted and fused due to heat generation or the like when the liquid composition flows through the flow path. Further, the coarse particles of the F polymer maintain high hardness even when heated, so that the fine particles are satisfactorily atomized and desired fine particles can be obtained. In particular, when the melting temperature is 380 ° C. or lower, fibrilization of fine particles is unlikely to occur. Therefore, when the melting temperature of the F polymer is in the above range, it is possible to promote the atomization of coarse particles, and it is easy to suppress the fibrilization of fine particles.

The D50 of the coarse particles is preferably less than the diameter of the flow path, more preferably more than 1 μm and less than 10 μm, particularly preferably more than 2 μm and less than 8 μm, and even more preferably more than 3 μm and less than 6 μm. When the D50 of the coarse particles is within the above range, the flow path can be smoothly circulated without clogging, and fine particles having a target particle size can be obtained.
The coarse particle D90 is preferably less than the diameter of the flow path, more preferably 15 μm or less, particularly preferably 13 μm or less, and even more preferably 11 μm or less. When the D90 of the coarse particles is in the above range, the flow path is less likely to be clogged.
As a method for producing such coarse particles, the method described in [0065] to [0069] of International Publication No. 2016/017801 can be adopted. As the coarse particles, commercially available desired particles may be used.

The dispersant in the present invention is a compound having a cloud point, which has a function of interacting with the surface of F polymer particles to stably disperse fine particles in a liquid dispersion medium. Here, the cloud point of the dispersant is a temperature at which the action disappears or extremely decreases due to the molecular motion accompanying the temperature rise.
Such a function of the dispersant is preferably a function due to a surface active action. That is, the dispersant in the present invention is preferably a surfactant. The cloud point in this case is a temperature at which the dispersant cannot dissolve or form micelles in the liquid dispersion medium used in the liquid composition, resulting in turbidity.
The cloud point of the dispersant is more than 50 ° C., preferably 60 ° C. or higher, and more preferably 70 ° C. or higher. The cloud point of the dispersant is preferably 100 ° C. or lower, more preferably 90 ° C. or lower. If a dispersant having a cloud point is used, not only is it easy to prepare a liquid composition having a desired viscosity, but it is also easy to suppress deterioration of the F polymer due to heat generation when the liquid composition is subjected to a wet jet mill. ..

The dispersant in the present invention is preferably a fluorine-based dispersant. The fluorine-based dispersant is a compound having a function of chemically and / or physically adsorbing the fine particles of the F polymer on the surface of the fine particles to stably disperse the fine particles in a liquid dispersion medium.
If the dispersant is a fluorine-based dispersant, the affinity with both the F polymer and the molecule of the liquid dispersion medium tends to increase, the interaction between the components in the wet jet mill method tends to improve, and the fine particles of coarse particles are efficiently atomized. Progress. Furthermore, the interaction between the surface of the formed fine particles and the fluorine-based dispersant tends to increase. As a result, it is easy to obtain a dispersion liquid in which fine particles are highly dispersed by a liquid dispersion medium due to the action of the fluorine-based dispersant.

The fluorine-based dispersant is preferably a compound (surfactant) having a hydrophobic moiety and a hydrophilic moiety containing a fluorine atom, and at least one selected from the group consisting of fluoromonool, fluoropolyol, fluorosilicone and fluoropolyether. Compounds are more preferred.
The fluorine content of the fluorine-based dispersant is preferably 10 to 50% by mass, more preferably 10 to 45% by mass, and even more preferably 15 to 40% by mass. In the above range, it is easy to obtain a dispersion liquid having excellent dispersion stability, which contains fine particles having a smaller particle size.
As the fluorine-based dispersant, the above-mentioned one compound having a fluorine content of 10 to 50% by mass is particularly preferable.
In addition, a preferable embodiment of the fluorine-based dispersant includes at least one compound selected from the group consisting of fluoromonool and fluoropolyol, and a more preferable embodiment is a group consisting of fluoromonool and fluoropolyol. A compound having a hydroxyl value of 10 to 100 mgKOH / g, which is at least one compound selected from the above, is mentioned, and a more preferable embodiment is the compound having a hydroxyl value of 10 to 100 mgKOH / g. Some compounds are mentioned.
The fluorine-based dispersant may be in the form of a polymer or may be in the form of a non-polymer. The fluorine-based dispersant is preferably nonionic.

These fluorine-based dispersants have excellent affinity with both F-polymers and liquid dispersion media. In the case of an aqueous dispersion medium, the fluorine-based dispersant is preferably fluoromonool, and in the case of a non-aqueous dispersion medium, the fluorine-based dispersant is preferably a fluoropolyol. Further, if the melting temperature of the F polymer is in the above range or the F polymer has the above functional groups, the affinity with the fluorine-based dispersant is further improved.

Unlike the F polymer and the liquid dispersion medium, fluoromonool is a non-polymeric fluorine-containing compound (surfactant) having one hydroxyl group.
The fluoropolypoly is a polymer-like fluorine-containing compound (surfactant) having two or more hydroxyl groups and a fluorine atom, unlike the F polymer and the liquid dispersion medium. In addition, some of the hydroxyl groups of the fluoropolyol may be chemically modified and modified.
Examples of the fluoropolyol include a main chain composed of a carbon chain derived from an ethylenically unsaturated monomer, and a polymer-like polyol having a fluorine-containing hydrocarbon group and a hydroxyl group as a side chain branched from the main chain. Here, the fluorine-containing hydrocarbon group is preferably a group having a tertiary carbon atom to which a plurality of (2 or 3) monovalent fluorine-containing hydrocarbon groups are bonded.

Fluoromonool preferably has a fluorine content of 10 to 50% by mass and a hydroxyl value of 40 to 100 mgKOH / g.
The fluoromonool is preferably a compound represented by the following formula (a).
Equation (a) ^Ra − (OQ ^a ) _ma −OH
The symbols in the formula have the following meanings.
^Ra represents a polyfluoroalkyl group or a polyfluoroalkyl group containing an ethereal oxygen atom, −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 an ethylene group (-CH ₂ CH _2- ) or a propylene group (-CH ₂ CH (CH ₃ )-) is preferable. Q ^a may be made from one group, it may also consist of two or more kinds of groups. When it is composed of two or more kinds of groups, the arrangement of the groups may be random or block.
ma represents an integer of 4 to 20, preferably 4 to 10.
The hydroxyl group of fluoromonool is preferably a secondary hydroxyl group or a tertiary hydroxyl group, and particularly preferably a secondary hydroxyl group.

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 (CH ₃ ) OH, F (CF ₂ ) ₆ CH ₂ CH ₂ (OCH ₂ CH ₂ ) ₇ OCH ₂ CH (CH ₃ ) OH, F (CF ₂ ) ₆ CH ₂ CH ₂ (OCH ₂ CH ₂ ) ₁₂ OCH ₂ CH (CH ₃ ) OH, F (CF ₂ ) ₄ CH ₂ CH ₂ (OCH ₂ CH ₂ ) ₇ OCH ₂ CH (CH ₃ ) OH.
Such fluoromonool can be obtained as a commercially available product (“Bluewet N083”, “Bluewet N050”, etc. manufactured by Arkroma Co., Ltd.).

The fluoropolyol preferably has a fluorine content of 10 to 45% by mass and a hydroxyl value of 10 to 35 mgKOH / g.
The fluoropolyol is preferably a copolymer of a compound represented by the formula (f) and a monomer represented by the formula (d), which will be described later.

The fluoropolyol has a unit based on a (meth) acrylate having a polyfluoroalkyl group or a polyfluoroalkenyl group (hereinafter, also referred to as “fluorine-containing (meth) acrylate”) and a polyoxyalkylene monool group (meth). Copolymers containing a unit based on an acrylate (hereinafter, also referred to as "hydroxyl-containing (meth) acrylate") are preferable. The (meth) acrylate is a general term for acrylates, methacrylates, and acrylate derivatives in which the hydrogen atom at the α-position of the acrylate is replaced with another atom or atomic group.

The fluorine-containing (meth) acrylate is preferably a compound represented by the following formula (f).
Equation (f) CH ₂ = CR ^f C (O) O-X ^f- Z ^f
The symbols in the formula have the following meanings.
R ^f represents a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group or a trifluoromethyl group.
X ^f represents an alkylene group, an oxyalkylene group or an alkyleneamide group.
Z ^f represents a perfluoroalkyl group or a perfluoroalkenyl group.
On the other hand, the hydroxyl group-containing (meth) acrylate is preferably a compound represented by the following formula (d).
Equation (d) CH ₂ = CR ^d C (O) O-X ^d1- X ^d2- OH
The symbols in the formula have the following meanings.
R ^d represents a hydrogen atom or a methyl group.
X ^d1 represents an alkylene group.
X ^d2 represents an oxyalkylene group.

Specific examples of the fluorine-containing (meth) acrylate include CH ₂ = CHCOO (CH ₂ ) ₂ (CF ₂ ) ₄ F, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (CF ₂ ) ₄ F, CH. ₂ = CHCOO (CH ₂ ) ₂ (CF ₂ ) ₆ F, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (CF ₂ ) ₆ F, CH ₂ = CHCOO (CH ₂ ) ₄ OCF (CF ₃ ) (C (CF (CF ₃ ) ₂ ) (= C (CF ₃ ) ₂ ), CH ₂ = CHCOO (CH ₂ ) ₄ OC (CF ₃ ) (= C (CF (CF ₃ ) ₂ )) (CF (CF ₃₎ ) ₂ ) can be mentioned.

Specific examples of the hydroxyl group-containing (meth) acrylate include CH ₂ = CHCOO (CH ₂ ) ₂ (OCH ₂ CH ₂ ) ₁₀ OH, CH ₂ = CHCOO (CH ₂ ) ₄ (OCH ₂ CH ₂ ) ₁₀ OH, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (OCH ₂ CH ₂ ) ₁₀ OH, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₄ (OCH ₂ CH ₂ ) ₁₀ OH, CH ₂ = CHCOO (CH) ₂ ) ₂ (OCH ₂ CH (CH ₃ )) ₁₀ OH, CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (OCH ₂ CH (CH ₃ )) ₁₀ OH.

The ratio of the units based on fluorine-containing (meth) acrylate to all the units contained in the fluoropolyol is preferably 20 to 60 mol%.
The ratio of the unit based on the hydroxyl group-containing (meth) acrylate to all the units contained in the fluoropolyol is preferably 40 to 80 mol%.
The ratio of the amount of the unit based on the hydroxyl group (meth) acrylate to the amount of the unit based on the fluorine-containing (meth) acrylate contained in the fluoropolyol is preferably 1 to 5, and more preferably 1 to 2.

The fluoropolyol may contain only a unit based on a fluorine-containing (meth) acrylate and a unit based on a hydroxyl-containing (meth) acrylate, and may further contain other units.
The fluorine content of the fluoropolyol is preferably 10 to 45% by mass, more preferably 15 to 40% by mass.
The fluoropolyol is preferably nonionic.
The weight average molecular weight of the fluoropolyol is preferably 2000 to 80,000, more preferably 6000 to 20000.

Examples of fluorosilicone include polyorganosiloxane having a CF bond in a part of the side chain.
Examples of the fluoropolyether include compounds in which a part of the hydrogen atom of the polyoxyalkylene alkyl ether is replaced with a fluorine atom. The fluoropolyether also includes a monool form of the compound.

The liquid dispersion medium in the present invention is a dispersion medium for dispersing F polymer particles (coarse particles and fine particles). This liquid dispersion medium is a compound that is liquid at 25 ° C. and does not react with the F polymer. Specifically, the liquid dispersion medium is preferably a compound having a boiling point lower than the boiling point of components other than the liquid dispersion medium contained in the dispersion liquid and which can be removed by heating.
Examples of such a liquid dispersion medium include water, alcohol (methanol, ethanol, isopropanol, etc.), nitrogen-containing compounds (N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, etc.), and sulfur-containing compounds. (Dimethyl sulfoxide, etc.), ether (diethyl ether, dioxane, etc.), ester (ethyl lactate, ethyl acetate, etc.), ketone (methyl ethyl ketone, methyl isopropyl ketone, cyclopentanone, cyclohexanone, etc.), glycol ether (ethylene glycol monoisopropyl ether, etc.) ), Cellosolve (methyl cellosolve, ethyl cellosolve, etc.). As the liquid dispersion medium, one of these compounds may be used alone, or two or more of these compounds may be used in combination.
The liquid dispersion medium may be an aqueous dispersion medium or a non-aqueous dispersion medium, and a non-aqueous dispersion medium is preferable from the viewpoint of adjusting the viscosity of the liquid composition to a desired range.

As the non-aqueous dispersion medium, nitrogen-containing compounds, sulfur-containing compounds, ethers, esters, ketones, glycol ethers and the like are preferable. In this case, the liquid dispersion medium is preferably an organic dispersion medium having a relatively low specific heat at 20 ° C. When such a liquid dispersion medium is used, the heat dissipation effect of the liquid composition is enhanced when the liquid composition is subjected to the wet jet mill method, and fusion of the fine particles obtained by micronization can be prevented. In addition, it is possible to prevent the irregular shape and fibrillation of the fine particles. The specific value of the specific heat is preferably 3 J / (g · K) or less, more preferably 2.8 J / (g · K) or less, and further preferably 1.8 to 2.5 J / (g · K). preferable.

The boiling point of the liquid dispersion medium is preferably 80 to 275 ° C, more preferably 125 to 250 ° C.
Examples of the liquid dispersion medium satisfying the above conditions include N-methyl-2-pyrrolidone (boiling point: 202 ° C.), dimethylacetamide (boiling point: 165 ° C.), cyclohexanone (boiling point: 155 ° C.), N, N-dimethyl. Examples thereof include formamide, (boiling point: 153 ° C.), and methyl ethyl ketone (specific heat: 2.1 J / (g · K), boiling point: 80 ° C.).

The liquid composition in the present invention may contain other components as long as the effects of the present invention are not impaired. Other components may or may not be dissolved in the liquid composition.
Other components include resins (non-curable resins, curable resins, etc.), thixo-imparting agents, defoaming agents, inorganic fillers, reactive alkoxysilanes, dehydrating agents, plasticizers, weather resistant agents, antioxidants, and thermosetting agents. Examples thereof include stabilizers, lubricants, antistatic agents, whitening agents, colorants, conductive agents, mold release agents, surface treatment agents, viscosity modifiers, and flame retardant agents.
Examples of the non-curable resin include thermosetting resins and non-meltable resins. Examples of the heat-meltable resin include thermoplastic polyimide. Examples of the non-meltable resin include a cured product of a curable resin.
Examples of the curable resin include a polymer having a reactive group, an oligomer having a reactive group, a small molecule compound, and a small molecule compound having a reactive group. Examples of the reactive group include a carbonyl group-containing group, a hydroxy group, an amino group and an epoxy group.

Examples of the curable resin include epoxy resin, thermosetting polyimide, polyamic acid which is a polyimide precursor, acrylic resin, phenol resin, polyester resin, polyolefin resin, modified polyphenylene ether resin, polyfunctional cyanate ester resin, and polyfunctional maleimide- Examples thereof include cyanate ester resin, polyfunctional maleimide resin, vinyl ester resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, and melamine-urea cocondensation resin.
Among them, from the viewpoint of using the dispersion liquid obtained in the present invention for the purpose of printed wiring board, the curable resin includes a thermosetting polyimide, a polyimide precursor, an epoxy resin, an acrylic resin, a bismaleimide resin or a polyphenylene ether resin. Preferably, an epoxy resin or a polyphenylene ether resin is more preferable.

Specific examples of the epoxy resin include naphthalene type epoxy resin, cresol novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, and aliphatic chain epoxy resin. Cresol novolac type epoxy resin, phenol novolac type epoxy resin, alkylphenol novolac type epoxy resin, aralkyl type epoxy resin, biphenol type epoxy resin, dicyclopentadiene type epoxy resin, trishydroxyphenylmethane type epoxy compound, phenol and phenolic hydroxyl group Examples thereof include an epoxidized product of a condensate with an aromatic aldehyde, a diglycidyl etherified product of bisphenol, a diglycidyl etherified product of naphthalenediol, a glycidyl etherified product of phenol, a diglycidyl etherified product of alcohol, and triglycidyl isocyanurate.

As the bismaleimide resin, a resin composition (BT resin) in which a bisphenol A type cyanate ester resin and a bismaleimide compound are used in combination, which is described in JP-A-7-70315, is described in International Publication No. 2013/008667. Examples of the resin composition of the above, and the resin composition described in the background art thereof.
Examples of the diamine and polyvalent carboxylic acid dianhydride forming the polyamic acid include [0020] of Japanese Patent No. 5766125, [0019] of Japanese Patent No. 5766125, and [0055] and [0055] of Japanese Patent Application Laid-Open No. 2012-145676. 0057].
Among them, aromatic amines such as 4,4'-diaminodiphenyl ether and 2,2-bis [4- (4-aminophenoxy) phenyl] propane, and pyromellitic dianhydride, 3,3', 4,4'. -Preferably in combination with an aromatic polyvalent carboxylic dianhydride such as biphenyltetracarboxylic dianhydride, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride.

Examples of the heat-meltable resin include a thermoplastic resin such as thermoplastic polyimide and a heat-meltable cured product of a curable resin.
Examples of the thermoplastic resin include polyester resin, polyolefin resin, styrene resin, polycarbonate, thermoplastic polyimide, polyarylate, polysulfone, polyallylsulfone, aromatic polyamide, aromatic polyetheramide, polyphenylensulfide, polyallyl etherketone, and polyamide. Examples thereof include imide, liquid crystal polyester and polyphenylene ether, and thermoplastic polyimide, liquid crystal polyester or polyphenylene ether is preferable.

The viscosity of the liquid composition in the present invention can be adjusted to 10,000 mPa · s or less depending on the type and / or blending amount of each component, the presence or absence of blending of other components, and the temperature of the liquid composition. On the other hand, when a liquid composition having a viscosity of more than 10,000 mPa · s is subjected to a wet jet mill method, fine particles are likely to be fibrillated. In the present invention, since the viscosity of the liquid composition is adjusted to 10000 mPa · s or less, the components in the liquid composition can be brought into high contact with each other to prevent fibrillation and promote the atomization of coarse particles. In addition, since many dispersants adhere (adsorb) to the surface of the fine particles obtained by micronization, they are stably dispersed in a liquid dispersion medium.
The viscosity of the liquid composition is preferably 5000 mPa · s or less, more preferably 1000 mPa · s or less. When the viscosity of the liquid composition is not more than the above upper limit value, the above effect is further improved.
The viscosity of the liquid composition is preferably 1 mPa · s or more, more preferably 5 mPa · s or more, particularly preferably 10 mPa · s or more, and particularly preferably 20 mPa · s or more. When the viscosity of the liquid composition is at least the above lower limit value, the components in the liquid composition are easily brought into contact with each other to a high degree even when subjected to the wet jet mill method, and the productivity is excellent. Therefore, the coarse particles can be sufficiently made into fine particles, the interaction of the dispersant on the surface of the fine particles is enhanced, and the fine particles can be stably dispersed in the liquid dispersion medium.

Examples of the treatment (dispersion treatment) for mixing each component include ultrasonic treatment, stirring treatment, and shaking treatment. Sonication or stirring treatment is preferable from the viewpoint that coarse particles can be sufficiently dispersed in the liquid composition and aggregation can be suppressed. In addition, you may use two or more kinds of the said processing together.
The temperature in the treatment is preferably 35 to 60 ° C. from the viewpoint of promoting the dispersion of coarse particles.
The stirring speed in the stirring treatment is preferably 100 to 1000 rpm. By the stirring treatment at such a stirring speed, it is easy to suppress the fibrilization of the coarse particles while uniformly dispersing the coarse particles in the liquid composition.
The flow form of the liquid composition in the stirring treatment may be any of a swirling flow, an ascending flow, a vertical circulation flow, and a radiating flow. However, from the viewpoint of promoting the redispersion of the sedimented component in the liquid composition, an ascending flow or a vertical circulation flow is preferable as the flow form.
In the stirring process, a baffle plate may be installed in the stirring tank to control the flow form, or the installation position and / or the installation angle of the stirring device may be adjusted to eccentric the flow form.

The amount of coarse particles contained in the liquid composition is preferably 1 to 50% by mass, more preferably 5 to 45% by mass, still more preferably 10 to 40% by mass.
The amount of the dispersant contained in the liquid composition is preferably 1 part by mass or more, more preferably 5 to 50 parts by mass, and even more preferably 10 to 40 parts by mass with respect to 100 parts by weight of the coarse particles.
When the amount of each component is within the above range, the viscosity of the liquid composition can be easily adjusted to a desired range. In addition, the average particle size of the fine particles in the finally obtained dispersion can be optimized, and the dispersion stability of the fine particles in the dispersion is improved.

In the wet jet mill method, the liquid composition is pressure-flowed through a small-diameter flow path (orifice). At this time, a high shearing force is applied to the liquid composition, and each component in the liquid composition is in high contact with each other. Therefore, the coarse particles are made into fine particles by contact with each other, and fine particles are generated. In particular, in the present invention, since the viscosity of the liquid composition is adjusted to the above range, the shearing force applied to the coarse particles is high, and the coarse particles are smoothly and efficiently atomized. In addition, the dispersant is highly contacted with the fine particles, and due to these interactions, the dispersant adheres to the surface of the fine particles. As a result, a dispersion liquid in which fine particles are stably dispersed in a liquid dispersion medium can be obtained.

Examples of the device capable of carrying out the wet jet mill method include a nano jet pal manufactured by Joko Co., Ltd. and an ultra-high pressure wet atomizing device manufactured by Yoshida Kogyo Co., Ltd.
The pressurizing pressure in the wet jet mill method is preferably 50 to 200 MPa, more preferably 100 to 170 MPa. By pressurizing the liquid composition with such a pressure, the atomization of coarse particles can be further promoted.
The diameter of the flow path is appropriately set according to the viscosity of the liquid composition and the particle size of the coarse particles of the F polymer, and is preferably 200 μm or less, more preferably 180 μm or less, still more preferably 50 to 150 μm. If the liquid composition having the above viscosity is circulated through such a small-diameter flow path, the coarse particles are made into fine particles and the stable dispersibility of the fine particles is further enhanced.

The D50 of the obtained fine particles is preferably 1 μm or less, preferably 0.05 to 0.8 μm, further preferably 0.1 to 0.6 μm, and particularly preferably 0.15 to 0.4 μm. Such D50 fine particles have good fluidity and dispersibility, and for example, when an insulating resin layer of a printed wiring board is formed, the electrical characteristics (low dielectric constant, etc.) and heat resistance of the F polymer are most likely to be exhibited. ..
The D90 of the fine particles is preferably 3 μm or less, more preferably 2.5 μm or less, and even more preferably 2 μm or less. The fine particles of D90 have good fluidity and dispersibility. For example, when an insulating resin layer of a printed wiring board is formed, the electrical characteristics (low dielectric constant, etc.) and heat resistance of the F polymer are most likely to be exhibited. ..

Specific embodiments of the D50 and D90 of the obtained fine particles include an embodiment in which D50 is 0.5 μm or less and D90 is 2 μm or less.
Further, as another specific embodiment, there is an embodiment in which D50 is 0.05 to 1 μm and D90 is 1.1 to 3 μm, and as a more preferable embodiment, D50 is 0.05 to 0. An embodiment in which the thickness is 5 μm and the D90 is 1.1 to 2 μm can be mentioned.
The sparsely packed bulk density of the fine particles is preferably 0.08 to 0.5 g / mL.
The densely packed bulk density of the fine particles is preferably 0.1 to 0.8 g / mL.

The liquid composition once subjected to the wet jet mill method may be used as it is as a dispersion liquid, and the liquid composition after being subjected to the wet jet mill method is again subjected to the wet jet mill method to disperse. It may be used as a liquid. That is, the liquid composition may be circulated and circulated in the flow path. When the liquid composition is repeatedly subjected to a wet jet mill method, desired D50 fine particles can be easily obtained.
In the latter case, it is preferable to forcibly cool the liquid composition after being subjected to the wet jet mill method. When the cooled liquid composition is subjected to the wet jet mill method again, deterioration or deterioration of the F polymer is prevented, and fibrillation of fine particles is unlikely to occur. Such an effect is more remarkable when the liquid dispersion medium having the specific heat is used.

The temperature of the liquid composition after being subjected to the wet jet mill method is preferably 75 ° C. or lower, more preferably 50 ° C. or lower. At such a temperature, changes in the viscosity of the liquid composition due to alteration or deterioration of the F polymer and aggregation of fine particles are unlikely to occur.
To lower the temperature of the liquid composition after being subjected to the wet jet mill method, a method of lowering the temperature of the liquid holder before passing through the nozzle defining the flow path and a method of lowering the temperature of the piping after passing through the nozzle. However, it is preferable to adopt both methods.

When the liquid composition is repeatedly applied to the wet jet mill method, the number of times is not particularly limited, but is preferably 10 to 70 times, more preferably 20 to 60 times, and even more preferably 30 to 50 times. If the number of times is too small, the effect of repeatedly applying the liquid composition to the wet jet mill method may not be sufficiently obtained depending on the diameter of the flow path, the pressure of pressurization, and the like. On the other hand, even if the number of times is increased more than necessary, the effect of atomizing coarse particles corresponding to the number of times and the effect of improving the stable dispersibility of the fine particles may not be obtained.

When the liquid composition is circulated and circulated in the flow path, when the total amount of the liquid composition, the flow rate of the flow path, and the circulation time are V, v, and t in this order, the value of v × t / V (the product of v and t). Is divided by V. Hereinafter, also referred to as “pass count”) is preferably adjusted to more than 10. The number of passes is more preferably 12 or more, and particularly preferably 20 or more. The upper limit of the number of passes is preferably 100 or less, more preferably 50 or less, from the viewpoint of the productivity of the dispersion liquid. The total amount of the liquid composition is the total volume (unit: L) of the liquid composition to be used for production, the flow rate of the flow path is the flow rate of the flow path outlet (unit: L / hr), and the circulation time is the operation of the manufacturing apparatus. The time (unit: hr) can be determined from the amount of the liquid composition, the apparatus capacity, and the production time.

In the present invention, an F polymer having a predetermined melt viscosity is selected, the liquid composition contains a dispersant, and the viscosity is adjusted to a predetermined range. Therefore, such a circulation process causes alteration of the F polymer. The coarse particles can be efficiently crushed into fine particles while being suppressed. This effect is particularly remarkable when the liquid dispersion medium is an aqueous dispersion medium and the dispersant is fluoromonool, or when the liquid dispersion medium is a non-aqueous dispersion medium and the dispersant is a fluoropolyx. Easy to develop.

In the dispersion liquid obtained by the circulation process, the fine particles D50 and D90 preferably have a D50 of 1 μm or less and a D90 of less than 2 μm, and a D50 of 0.50 μm or less and a D90 of 2.0 μm or less. Is more preferable. In this case, D50 is usually 0.05 μm or more and D90 is 1.1 μm or more. According to the present invention, a dispersion liquid containing fine particles of F polymer having such a narrow particle size distribution can be efficiently and easily produced.

The dispersion liquid obtained in the present invention is a dispersion liquid in which fine particles of F polymer are dispersed in a liquid dispersion medium and has excellent dispersion stability in a high temperature environment and compatibility with other materials. The dispersion liquid obtained in the present invention can be used as a coating agent or the like capable of forming a dense and smooth layer containing an F polymer on the surface of various base materials when applied.
For example, by using the dispersion liquid obtained in the present invention, it is possible to easily manufacture a resin-coated metal foil having an insulating resin layer, which is used for a printed wiring board or the like used for transmitting a high-frequency signal.
That is, if the dispersion liquid obtained in the present invention is applied to the surface of the metal foil and heated, a resin-attached metal foil having an insulating resin layer on the surface of the metal foil can be produced. The insulating resin layer may be formed on at least one surface of the metal foil. When the insulating resin layer is formed on both sides of the metal foil, it is preferable to apply the dispersion liquid to one surface of the metal foil and then apply the dispersion liquid to the other surface. At the time of heating, the dispersion liquids on both sides may be fired at once, or the dispersion liquids on each side may be fired individually.

Examples of the material of the metal foil include copper, copper alloy, stainless steel, nickel, nickel alloy (including 42 alloy), aluminum, aluminum alloy, titanium, titanium alloy and the like.
Examples of the metal foil include rolled copper foil and electrolytic copper foil. A rust preventive layer (oxide film such as chromate), a heat resistant layer, or the like may be formed on the surface of the metal foil.
The ten-point average roughness of the surface of the metal foil is preferably 0.01 to 1.5 μm.
The thickness of the metal foil may be any thickness as long as it can exert its function in the application of the metal foil with resin.
The surface of the metal foil may be treated with a silane coupling agent, the entire surface of the metal foil may be treated with a silane coupling agent, or a part of the surface of the metal foil may be treated with a silane coupling agent. It may have been done.

The warpage rate of the metal foil with resin is particularly preferably 7% or less. In this case, the processability of the metal foil with resin and the physical characteristics of the processed product (transmission characteristics of the printed circuit board, etc.) are excellent.
The dimensional change rate of the metal foil with resin is particularly preferably ± 0.2% or less. In this case, it is easy to process the metal foil with resin into a printed circuit board and further multi-layer it.
The water contact angle on the surface of the insulating resin layer is preferably 70 to 100 °. In this case, the adhesiveness of the insulating resin layer is excellent, and the physical characteristics of the processed product (electrical characteristics of the printed circuit board, etc.) are excellent.
The thickness of the insulating resin layer is preferably 1 to 50 μm. In this range, it is easy to balance the electrical characteristics and the warpage rate of the printed circuit board obtained from the metal foil with resin. When the metal foil with resin has insulating resin layers on both sides of the metal foil, the insulating resin layers may be the same.
The relative permittivity of the insulating resin layer is preferably 2.0 to 3.5. In this case, a metal foil with a resin can be suitably used for a printed circuit board or the like that requires a low dielectric constant.
The Ra on the surface of the insulating resin layer is preferably 2.2 to 8 μm. In this range, it is easy to balance the adhesiveness and workability of the resin-attached metal foil.

The coating method may be any method as long as a stable wet film composed of a powder dispersion is formed on the surface of the metal foil after coating, and is a spray method, a roll coating method, a spin coating method, a gravure coating method, or a micro gravure coating method. , Gravure offset method, knife coating method, kiss coating method, bar coating method, die coating method, fountain Mayer bar method, slot die coating method and the like.

For heating after coating the dispersion liquid, it is preferable to heat in a low temperature region to distill off the liquid dispersion medium. The temperature in the low temperature region is preferably 80 ° C. or higher and lower than 180 ° C. In this case, it is easy to form a metal foil with a resin having excellent adhesiveness without impairing the physical properties of the metal foil and the insulating resin layer.
Examples of the heating method in the low temperature region include a method using an oven, a method using a ventilation drying oven, a method of irradiating heat rays such as infrared rays, and the like.
The heating atmosphere in the low temperature region may be either under normal pressure or under reduced pressure. The atmosphere in the low temperature region is any of an oxidizing gas atmosphere (oxygen gas, etc.), a reducing gas atmosphere (hydrogen gas, etc.), and an inert gas atmosphere (helium gas, neon gas, argon gas, nitrogen gas, etc.). It may be.

The heating after the application of the dispersion liquid is preferably carried out at a temperature (high temperature region) at which the F polymer is fired. As a result, the fine particles of the F polymer are densely packed and fused, so that an insulating resin layer having excellent surface properties is likely to be formed.
Examples of the heating method in the high temperature region include the same method as the heating method in the low temperature region. In order to improve the smoothness of the surface of the insulating resin layer, pressure may be applied with a heating plate, a heating roll, or the like. As a heating method, a method of irradiating far infrared rays is preferable because it can be fired in a short time and the far infrared rays furnace is relatively compact. The heating method may be a combination of infrared heating and hot air heating.
As the heating atmosphere in the high temperature region, the same conditions as those in the low temperature region can be adopted.
The temperature in the high temperature region is preferably 250 ° C. to 400 ° C. or lower.
The time for holding in the high temperature region is preferably 30 seconds to 5 minutes.

In order to control the expansion of the metal foil with resin and further improve the adhesiveness of the insulating resin layer, the surface of the insulating resin layer is subjected to annealing treatment, corona discharge treatment, atmospheric pressure plasma treatment, vacuum plasma treatment, etc. Surface treatments such as UV ozone treatment, excimation treatment, chemical etching, and silane coupling treatment may be performed.
The temperature, pressure and time in the annealing treatment are preferably 120 to 180 ° C., 0.005 to 0.015 MPa and 30 to 120 minutes in this order.
Examples of the plasma irradiation device in plasma processing include a high frequency induction method, a capacitively coupled electrode method, a corona discharge electrode-plasma jet method, a parallel plate type, a remote plasma type, an atmospheric pressure plasma type, and an ICP type high density plasma type.
Examples of the gas used for the plasma treatment include oxygen gas, nitrogen gas, rare gas (argon and the like), hydrogen gas, and ammonia gas, and rare gas or nitrogen gas is preferable. Specific examples of the gas used for the plasma treatment include argon gas, a mixed gas of hydrogen gas and nitrogen gas, and a mixed gas of hydrogen gas, nitrogen gas and argon gas.
The atmosphere in the plasma treatment is preferably an atmosphere in which the volume fraction of the noble gas or nitrogen gas is 100% by volume. By performing the plasma treatment in such an atmosphere, Ra on the surface of the insulating resin layer can be adjusted to 2 μm or less, and fine irregularities can be easily formed on the surface of the insulating resin layer.

For the metal foil with resin, a substrate may be laminated on the surface of the insulating resin layer.
Examples of the substrate include a heat-resistant resin film, a prepreg which is a precursor of a fiber-reinforced resin plate, a laminate having a heat-resistant resin film layer, and a laminate having a prepreg layer.
The prepreg is a sheet-like substrate in which a base material (toe, woven cloth, etc.) of reinforcing fibers (glass fibers, carbon fibers, etc.) is impregnated with a thermosetting resin or a thermoplastic resin.
Examples of the laminating method include a method of heat-pressing the metal foil with resin and the substrate.
When the substrate is a prepreg, the press temperature is preferably equal to or lower than the melting temperature of the F polymer.
When the substrate is a heat-resistant resin film, the press temperature is preferably 310 to 400 ° C.
The hot press is preferably performed in a reduced pressure atmosphere from the viewpoint of suppressing air bubbles from being mixed into the interfaces of the substrate, the insulating resin layer, and the metal foil and suppressing deterioration due to oxidation, and is preferably performed at a vacuum degree of 20 kPa or less. More preferred.
Further, in the hot press, it is preferable that the temperature is raised after the reduced pressure atmosphere reaches the above-mentioned degree of vacuum in a state where the insulating resin layer is softened, that is, in a state where there is a certain degree of fluidity and adhesion.
The pressure in the hot press is preferably 0.2 to 10 MPa.

The metal leaf with resin and its laminate as described above can be used for manufacturing a printed wiring board as a flexible copper-clad laminate or a rigid copper-clad laminate.
For example, a method of processing a metal foil of a metal foil with a resin into a metal wiring having a predetermined pattern by etching or the like, or an electrolytic plating method (semi-additive method (SAP method), a modified semi-additive method (MSAP method)) of a metal foil with a resin. By using the method of processing into metal wiring by (etc.), a printed wiring board can be manufactured from a metal foil with resin.
In the production of the printed wiring board, after forming the metal wiring (conductor circuit), an interlayer insulating film may be formed on the metal wiring, and further the metal wiring may be formed on the interlayer insulating film. The interlayer insulating film can be formed by, for example, the dispersion liquid.
In the manufacture of the printed wiring board, a solder resist may be laminated on the metal wiring.
In the manufacture of the printed wiring board, a coverlay film may be laminated on the metal wiring. The solder resist and the coverlay film may be formed by the above dispersion liquid.

Although the method for producing the dispersion liquid of the present invention has been described above, the present invention is not limited to the configuration of the above-described embodiment.
For example, the method for producing a dispersion liquid of the present invention may additionally have any other step in the configuration of the above embodiment, or may be replaced with any step that produces the same action.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.
1. 1. Preparation of each component 1-1. Coarse particles of F polymer

(Coarse particles A)
Polymers containing 98.0 mol%, 0.1 mol% and 1.9 mol% of TFE units, NAH-based units and PPVE-based units, respectively, obtained by the procedure described in WO 2016/017801. (Melting temperature: 300 ° C., Melting viscosity at 380 ° C.: 3 × 10 ⁵ Pa · s) powder (D50: 2.6 μm, D90: 7.1 μm).
(Coarse particles B)
Powder (D50:) of polymer containing 98.0 mol% and 2.0 mol% of TFE units and units based on PPVE in this order (melting temperature: 305 ° C., melt viscosity at 380 ° C.: 3 × 10 ^{5 Pa · s).} 3.5 μm, D90: 9.2 μm).
(Coarse particles C)
A polymer containing 88.0 mol% and 12.0 mol% of TFE units and HFP-based units in this order, obtained by removing the liquid dispersion medium of FEP dispersion 120-JRB (manufactured by Mitsui DuPont Fluorochemical). Melting temperature: 270 ° C., 380 ° C. melting viscosity: 2 × 10 ⁵ Pa · s) powder (D50: 0.4 μm, D90: 1.2 μm).
(Coarse particle D)
PTFE powder (KTL-500F manufactured by Kitamura Co., Ltd.), which is a polymer (melting temperature: 327 ° C., 380 ° C., melt viscosity: 1 × 10 ⁹ Pa · s) powder (D50) containing 100.0 mol% of TFE units. : 0.7 μm, D90: 1.0 μm).
(Coarse particle E)
PTFE powder (KTL-1N, manufactured by Kitamura Co., Ltd.), which is a polymer (melting temperature: 327 ° C., 380 ° C., melt viscosity: 1 × 10 ¹¹ Pa · s) powder (D50) containing 100.0 mol% of TFE units. : 2.8 μm, D90: 4.2 μm).

The physical characteristics of each polymer and powder were measured as follows.
<Melting viscosity>
For the melt viscosity, the complex viscosity (unit: Pa · s) was measured under the following conditions.
Device: Dynamic viscoelasticity measuring device (MCR302 manufactured by Anton Pearl Co., Ltd.)
Measurement method: Parallel plate Φ25 mm
Measurement temperature: 380 ° C
Shedding frequency: 0.05Hz
<Melting temperature>
Using a differential scanning calorimeter (DSC-7020 manufactured by Seiko Instruments Inc.), record the melting peak when the polymer is heated at a rate of 10 ° C./min, and set the temperature (° C.) corresponding to the maximum value as the melting temperature. And said.
<Powder D50 and D90>
The powder was dispersed in water and measured using a laser diffraction / scattering type particle size distribution measuring device (LA-920 measuring device manufactured by HORIBA, Ltd.).

1-2. Dispersant (Fluorine-based dispersant 1)
_{CH 2} = CHCOO (CH ₂ ) ₄ OCF (CF ₃ ) (C (CF (CF ₃ ) ₂ ) (= C (CF ₃ ) ₂ ) and CH ₂ = CHCOO (CH ₂ ), which are nonionic fluoropolyols. ₄ (OCH ₂ CH ₂ ) A _{copolymer obtained by polymerizing 10} OH at a molar ratio of 1: 1 (weight average molecular weight: about 10,000, cloud point: 62 ° C.).
(Fluorine-based dispersant 2)
CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ (CF ₂ ) ₆ F homopolymer.
(Fluorine-based dispersant 3)
Nonionic fluoromonool, F (CF ₂ ) ₆ CH ₂ (OCH ₂ CH ₂ ) ₇ OCH ₂ CH (CH ₃ ) OH, cloud point: 60 ° C.).
(Non-fluorine-based dispersant 1)
A dispersant having a hydroxyl group and a polyoxyethylene group that does not contain a fluorine atom (cloud point: 48 ° C.).
1-3. A liquid dispersion medium N-methyl-2-pyrrolidone (hereinafter, also referred to as “NMP”) and methyl ethyl ketone (hereinafter, also referred to as “MEK”) were prepared.

2. Evaluation 2-1. Difference in effect due to different types of F polymer (Example 1)
After 75 parts by mass of NMP, 10 parts by mass of the fluorine-based dispersant 1 and 15 parts by mass of coarse particles A were put into the pot, zirconia balls were put into the pot. Then, the pot was rolled under the condition of 150 rpm × 1 hour to obtain a liquid composition A having a viscosity of 200 mPa · s in which coarse particles A were dispersed.
Next, the liquid composition A was subjected to a wet jet mill method under the following conditions, and the coarse particles A were made into fine particles to obtain a dispersion liquid having a viscosity of 300 mPa · s in which the fine particles were dispersed.

<Conditions for wet jet mill>
Equipment: JN100 (manufactured by Jokko Co., Ltd.)
Nozzle (flow path) diameter: 100 μm
Pressurized pressure: 150 MPa
Number of passes: 30 times Liquid holder temperature: 15 ° C
Temperature after passing through the nozzle: 50 ° C
Viscosity of liquid composition: 200 mPa · s
In the wet jet mill method, the liquid holder was cooled by passing a chiller through a cooling jacket, and the temperature of the liquid composition in the liquid holder (liquid holder temperature) was set to 15 ° C. Similarly, after passing through the nozzle, the temperature of the liquid composition after passing through the nozzle (temperature after passing through the nozzle) was set to 50 ° C. by winding the trace through which the chiller was passed around the metal pipe.
These temperatures are measured by applying a contact thermocouple to the liquid holder and the metal piping portion after passing through the nozzle.

(Examples 2 to 7)
Liquid compositions B to G were prepared in the same manner as in Example 1 except that the components were mixed so as to have the compositions shown in Table 1 below, and each of them was subjected to a jet mill method to obtain a dispersion liquid. .. The viscosities of the liquid compositions B to G were 20 to 1000 mPa · s. In Example 6, the obtained dispersion was thickened to about 1500 mPa · s.

<D50 and D90 of fine particles>
Using a laser diffraction / scattering type particle size distribution measuring device (LA-920 measuring device manufactured by HORIBA, Ltd.), D50 and D90 of fine particles contained in each dispersion were calculated.
<Agglutination after storage>
The dispersion obtained in each example was placed in a plastic bottle and allowed to stand at 40 ° C. for 1 month.
Then, the stirring blade was put into the dispersion liquid in the plastic bottle, and the mixture was stirred at 500 rpm for 30 minutes.
The stirred dispersion was applied to an A4 size substrate with a # 14 bar coater and dried. Aggregates of 500 μm or more existing on the coating film after drying were visually counted and evaluated according to the following criteria.

[Evaluation criteria]
◎ (Best): 1 or less ○ (Good): 1 or more, 5 or less △ (Yes): 5 or more, 10 or less × (No): 10 or more These evaluation results are shown in Table 2. ..

2-2. Difference in effect due to difference in viscosity of liquid composition (Examples 8 and 9 (Comparative Examples))
Liquid compositions H and I were prepared in the same manner as in Example 1 except that the components were mixed so as to have the compositions shown in Table 3 below, and each of them was subjected to a jet mill method to obtain a dispersion liquid. ..

For the dispersions obtained in each example, D50 and D90 of fine particles were determined, and the aggregation of the fine particles after storage was evaluated. These results are shown in Table 4.

2-3. Differences in effect due to differences in other conditions in the wet jet mill method (Examples 10 to 12)
A dispersion was obtained in the same manner as in Example 1 except that the pressurizing pressure was changed as shown in Table 5 below in the wet jet mill method.
(Examples 13 and 14)
A dispersion was obtained in the same manner as in Example 1 except that the nozzle diameter was changed as shown in Table 5 below in the wet jet mill method.
(Examples 15 and 16)
A dispersion was obtained in the same manner as in Example 1 except that the liquid holder temperature and the temperature after passing through the nozzle were changed as shown in Table 5 below in the wet jet mill method. The increase in temperature after passing through the nozzle in Example 15 is a result of omitting cooling of the liquid holder. On the other hand, the increase in the temperature after passing through the nozzle in Example 16 is a result of increasing the pressurizing pressure in the wet jet mill method and omitting the cooling of the metal pipe.
(Examples 17 and 18)
A dispersion was obtained in the same manner as in Example 1 above, except that the number of passes was changed as shown in Table 5 below in the wet jet mill method.

The dispersions obtained in each example were measured for D50 and D90 of fine particles, and the aggregation of fine particles after storage was evaluated.
These results are shown in Table 5.

As shown in Table 5, it was confirmed that when various conditions in the wet jet mill method were changed, the viscosity of the dispersion liquid, the particle size of the fine particles, and the degree of aggregation of the fine particles changed.

2-4. Difference in effect due to difference in type of dispersant (Example 19 (Comparative example))
A dispersion was obtained in the same manner as in Example 1 except that the non-fluorine-based dispersant 1 was used instead of the fluorine-based dispersant 1 and water was used instead of NMP. It was "x".
(Example 20 (Comparative example))
A dispersion liquid was obtained in the same manner as in Example 1 except that 10 parts by mass of MEK was added without using a fluorine-based dispersant, but the aggregated state after storage was “x”.
(Example 21)
After putting 67 parts by mass of water, 3 parts by mass of the fluorine-based dispersant 3 and 30 parts by mass of coarse particles A into the pot, zirconia balls were put into the pot. Then, the pot was rolled under the condition of 150 rpm × 1 hour to obtain a liquid composition H having a viscosity of 15 mPa · s in which coarse particles A were dispersed.
A wet jet mill (passes 30 times) was carried out in the same manner as in Example 1 except that the liquid composition H was used to obtain a dispersion liquid having a viscosity of 300 mPa · s in which fine particles in which coarse particles A were made into fine particles were dispersed. .. The D50 of the fine particles was 0.3 μm and the D90 was 1.5 μm. The aggregated state after storage of the dispersion was “⊚”.
(Example 22)
The liquid composition H was subjected to a wet jet mill under the same conditions as in Example 1 except that the number of passes was 10 times. Got The D50 of the fine particles was 0.6 μm and the D90 was 2.3 μm. The agglutinated state of the dispersion liquid after storage was “Δ”.

As shown in the above example, when a liquid composition having a predetermined viscosity containing a dispersant at a predetermined cloud point is subjected to a wet jet mill method, a dispersion liquid in which fine particles of F polymer are stably dispersed can be obtained.
Even if the viscosity of the liquid composition is adjusted to a predetermined range by using at least one of fluorosilicone and fluoropolyether as the dispersant instead of fluoropolyester, the same tendency as in each of the above examples can be obtained. The results shown are obtained.

The dispersion liquid obtained by the present invention can easily form an F polymer layer having excellent adhesiveness and crack resistance, and is suitable for a copper foil with a resin or a metal laminated board used for manufacturing a printed wiring board. Further, the dispersion liquid can be used for manufacturing molded products such as films and impregnated materials (prepregs, etc.), and has mold releasability, electrical properties, water and oil repellency, chemical resistance, weather resistance, heat resistance, and slipperiness. It is suitable for molded products for applications that require abrasion resistance and the like. The molded product obtained from the dispersion liquid is useful as an antenna part, a printed substrate, an aircraft part, an automobile part, a sports tool, a food industry product, a paint, a cosmetic, and the like, and specifically, a power module insulating layer. Electric wire coating materials (aircraft electric wires, etc.), electrical insulating tape, oil drilling insulating tape, printed substrate materials, electrode binders (for lithium secondary batteries, fuel cells, etc.), copy rolls, furniture, automobile dash Boats, covers for home appliances, sliding members (load bearings, sliding shafts, valves, bearings, gears, cams, belt conveyors, food transport belts, etc.), tools (shovels, shavings, cuttings, saws, etc.), boilers , Hopper, pipe, oven, baking mold, chute, die, toilet bowl, useful as container covering material.
The entire specification, scope of patent claims and abstract of Japanese Patent Application No. 2018-166187 filed on September 5, 2018 and Japanese Patent Application No. 2018-240870 filed on December 25, 2018. The contents are cited herein and incorporated as disclosure of the specification of the present invention.

Claims (15)

A viscosity of 10000 mPa · s containing coarse particles of a fluoroolefin polymer having a melt viscosity at 380 ° C. of 1 × 10 ² to 1 × 10 ¹⁰ Pa · s, a dispersant having a cloud point of more than 50 ° C., and a liquid dispersion medium. The following liquid composition was pressure-flowed through a flow path, the coarse particles were pulverized into fine particles having an average particle size smaller than the average particle size of the coarse particles, and the coarse particles were dispersed in the dispersant and the liquid dispersion medium. A method for producing a dispersion liquid, which obtains a dispersion liquid containing fine particles. The production method according to claim 1, wherein the melting temperature of the fluoroolefin polymer is 200 ° C. or higher. The production method according to claim 1 or 2, wherein the dispersant is a fluorine-based dispersant. The production method according to claim 3, wherein the fluorine-based dispersant is at least one compound selected from the group consisting of fluoromonool, fluoropolyol, fluorosilicone and fluoropolyether. The production method according to claim 3 or 4, wherein the fluorine content of the fluorine-based dispersant is 10 to 50% by mass. The compound according to any one of claims 1 to 5, wherein the dispersant is at least one compound selected from the group consisting of fluoromonool and fluoropolyol, and has a hydroxyl value of 10 to 100 mgKOH / g. Manufacturing method. The production method according to any one of claims 1 to 6, wherein the dispersant is fluoromonool and the liquid dispersion medium is an aqueous dispersion medium. The production method according to any one of claims 1 to 6, wherein the dispersant is a fluoropolyol and the liquid dispersion medium is a non-aqueous dispersion medium. The production method according to any one of claims 1 to 8, wherein the average particle size of the fine particles is 1 μm or less. The production method according to any one of claims 1 to 9, wherein the average particle size of the coarse particles is more than 1 μm and less than 10 μm. The production method according to any one of claims 1 to 10, wherein the liquid composition contains 1 part by mass or more of the dispersant with respect to 100 parts by mass of the coarse particles. The production method according to any one of claims 1 to 11, wherein the liquid composition contains 1 to 50% by mass of the coarse particles. The production method according to any one of claims 1 to 12, wherein the liquid composition is circulated and circulated in the flow path. Any of claims 1 to 13, wherein the liquid composition is circulated and circulated in the flow path under the condition that the value obtained by dividing the product of the flow rate of the flow path and the circulation time by the total amount of the liquid composition is more than 10. The manufacturing method according to item 1. The production method according to any one of claims 1 to 14, wherein the average particle size of the fine particles is 0.5 μm or less, and the volume-based cumulative 90% diameter of the fine particles is 2 μm or less.