TW202110986A - Method for producing thermosetting resin composition containing fluorine-based resin characterized in that there are almost no coarse foreign matters or air bubbles in the thermosetting resin cured product containing fluorine-based resin - Google Patents

Abstract

The object of the present invention is to provide a method for producing a thermosetting resin composition containing fluorine-based resin, in which even if the thermosetting resin composition is mixed with fine powder of fluorine-based resin, there are almost no coarse foreign matters or air bubbles in the thermosetting resin cured product containing fluorine-based resin. The solution of the present invention is a method for producing a thermosetting resin composition containing fluorine-based resin. The thermosetting resin composition at least contains: a fluorine-based resin non-aqueous dispersion at least containing a fluorine-based resin fine powder and a non-aqueous solvent; and a resin composition containing thermosetting resin. The present invention is characterized in that in the step of mixing the fluorine-based resin non-aqueous dispersion with the resin composition containing thermosetting resin, no foreign matters or air bubbles will be brought into the next step.

Description

Method for manufacturing thermosetting resin composition of fluorine-containing resin

The present invention relates to a method for producing a thermosetting resin composition containing a fluorine-containing resin. Although fine powders of the fluorine-containing resin are mixed, there is almost no coarse foreign matter or visible in the thermosetting resin composition of the fluorine-containing resin. bubble.

Generally speaking, in the production of thermosetting resins, it is an indispensable task to improve the quality of preventing the incorporation or defoaming of coarse foreign matter. In other words, if the coarse foreign matter or bubbles remain after being cured, the remaining foreign matter or foaming from the bubbles remaining in the drying and curing process will cause defects in the thermosetting resin, preventing thinning or thinning. The formation of wiring. Moreover, even if it is formed, it not only causes a significant decrease in its strength, but also becomes non-uniform in electromagnetic properties.

In the past, the foreign matter in the thermosetting resin composition is generally removed by filtration. The remaining air bubbles are placed in a vacuum environment during molding or after coating, and are removed at the same time as evaporating the solvent. (For example, refer to Patent Document 1). In recent years, the applicant has disclosed a thermosetting resin composition which is an oily solvent dispersion containing fine fluorine resin powder in the resin composition, which has high insulation, heat resistance, and electrical properties (low dielectric constant, Low dielectric tangent) and excellent in processability (for example, refer to Patent Documents 2 and 3).

These fluorine-based resin fine powders have poor wettability, and if they are dispersed in an oily solvent or an aqueous solvent, they are likely to contain foreign matter or bubbles caused by agglomerates. Therefore, in these prior arts, the oily solvent-based dispersion of the fluorine-based resin fine powder before mixing is made to have extremely good dispersibility and few bubbles. Even then, if it is mixed with a dissimilar liquid such as a thermosetting resin solution, agglomerates of fine fluorine resin powders often occur.

In addition, air bubbles slightly remain on the surface of the fluorine-based resin fine powder, and when mixed with the resin composition, air bubbles may be included. When mixing the oily solvent dispersion of the fluorine resin fine powder into the thermosetting resin solution, the amount of foreign matter or bubbles generated is so large that it cannot be compared with the previous step. The removal system is compared with the previous step of filtration or defoaming. It is extremely difficult, and many steps that can guarantee productivity are the status quo. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 7-7134 A (Examples, Paragraph 0024, etc.) [Patent Document 2] Japanese Patent Application Publication No. 2018-12786 (Abstract, application scope, paragraph 0060, etc.) [Patent Document 3] Japanese Unexamined Patent Publication No. 2018-12787 (Abstract, application scope, paragraph 0060, etc.)

[The problem to be solved by the invention]

The present invention intends to eliminate the above-mentioned conventional problems, etc., and aims to provide a method for producing a thermosetting resin composition of a fluorine-containing resin, which is used for the thermosetting of the fluorine-containing resin even though the fine powder of the fluorine-containing resin is mixed. Hardly any coarse foreign matter or air bubbles can be seen in the cured resin. [Means to Solve the Problem]

The inventors of the present invention intensively examined the above-mentioned conventional problems, and as a result, through the following first to fourth inventions, the above-mentioned method for producing a fluorine-containing resin thermosetting resin composition was completed.

That is, the first invention of the present invention is a method for producing a thermosetting resin composition containing a fluorine-containing resin, the thermosetting resin composition containing at least: a non-aqueous resin containing at least a fine powder of a fluorine-based resin and a non-aqueous solvent Dispersion, and resin composition containing thermosetting resin, characterized by: The step of mixing the non-aqueous dispersion of the fluorine-based resin and the resin composition containing the thermosetting resin includes a step including a treatment that does not bring foreign matter or air bubbles into the next step.

The second invention is a method for producing a thermosetting resin composition of a fluorine-containing resin as described in the first invention, wherein the fine powder of the fluorine resin is selected from polytetrafluoroethylene and fluorinated ethylene-propylene copolymer , Perfluoroalkoxy polymer, chlorotrifluoroethylene, tetrafluoroethylene-chlorotrifluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer, polychlorotrifluoroethylene form more than one kind of fluorine系Resin particles.

The third invention is a method for producing a thermosetting resin composition of a fluorine-containing resin as described in the first invention or the second invention, wherein the non-aqueous dispersion of the fluorine resin contains at least a fluorine-containing group A fluorine-based additive with a lipophilic group and/or a compound represented by the following formula (I).

The fourth invention is a method for producing a thermosetting resin composition of a fluorine-containing resin as described in any one of the first invention to the third invention, wherein the non-aqueous dispersion of the fluorine resin contains an amine A polymer of carbamic acid ester structure. [Effects of the invention]

According to the method of the present invention, the method includes the following steps: the step of mixing a non-aqueous dispersion of a fluorine resin containing at least a fluorine-based resin fine powder and a non-aqueous solvent and a resin composition containing a thermosetting resin includes Including a process that does not bring foreign matter or air bubbles into the next step; thereby, a method for manufacturing a thermosetting resin composition containing fluorine-based resin can be provided, which is mixed with fine powder of fluorine-based resin. There are almost no coarse foreign objects or bubbles in the cured thermosetting resin of fluorine-containing resin, and there is no aggregation of fine powder of fluorine-based resin. It can achieve low dielectric constant and low dielectric tangent while suppressing hindering The foreign matter of wiring pattern or interlayer adhesion is suitable for insulating layers of multilayer printed wiring boards, adhesives for circuit boards, laminates for circuit boards, coverlay films, prepregs, etc.

[The form of implementing the invention]

Hereinafter, embodiments of the present invention will be described in detail. The method for producing a thermosetting resin composition of fluorine-containing resin (hereinafter referred to as "the method of the present invention") of the present invention is a method for producing a thermosetting resin composition of fluorine-containing resin, wherein the thermosetting resin composition is at least Containing: a non-aqueous dispersion of a fluorine-based resin containing at least a fine powder of a fluorine-based resin and a non-aqueous solvent, and a resin composition containing a thermosetting resin. The manufacturing method is characterized by: The step of mixing the non-aqueous dispersion of the fluorine-based resin and the resin composition containing the thermosetting resin includes a step including a treatment that does not bring foreign matter or air bubbles into the next step.

[Non-aqueous dispersion of fluorine-based resin] The non-aqueous dispersion system of the fluorine-based resin used in the method of the present invention contains at least a fine powder of the fluorine-based resin and a non-aqueous solvent. Examples of usable fluorine resin fine powders include those selected from polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy polymer (PFA), and chlorotrifluoroethylene. (CTFE), tetrafluoroethylene-chlorotrifluoroethylene copolymer (TFE/CTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), polychlorotrifluoroethylene (PCTFE) at least one of the group For the fluorine resin particles, the primary particle size of these systems is preferably 1 μm or less. Among the above-mentioned fluorine-based resin particles, especially as materials with low specific permittivity and low dielectric tangent, it is suitable to use polytetrafluoroethylene (PTFE, specific permittivity 2.1, dielectric constant) which has the most excellent characteristics among resin materials. Electric tangent 0.0002).

Such a fluorine-based resin fine powder is obtained by an emulsion polymerization method, for example, it can be obtained by a generally used method such as the method described in the Fluorine Resin Handbook (edited by Takao Kurokawa, Nikkan Kogyo Shimbun). Furthermore, the aforementioned fluorine resin particles obtained by emulsion polymerization are aggregated and dried to form secondary particles aggregated with primary particle diameters, which are used as fine powder collectors, but various generally used methods for producing fine powders can be used.

As the particle size of the fluorine-based resin fine powder, the primary particle size is preferably 1 μm or less, and it is also preferable to have an average particle size of 1 μm or less in a non-aqueous dispersion. In terms of stable dispersion in a non-aqueous solvent, the primary particle size is preferably 0.5 μm or less, more preferably 0.3 μm or less, to form a more uniform dispersion. In addition, if the average particle size of the fluorine resin fine powder in the non-aqueous dispersion exceeds 1 μm, it will tend to settle and it will be difficult to stably disperse, which is not suitable. It is preferably 0.5 μm or less, more preferably 0.3 μm or less.

In the method of the present invention, as a method of measuring the primary particle size, a volume-based average particle size (50% volume diameter) measured by the laser diffraction and scattering method, dynamic light scattering method, image imaging method, etc., can be used. , Median diameter), but the fluorine-based resin particles that are dried into a powder state have strong cohesion between primary particles, and sometimes it is difficult to easily measure the primary particles by laser diffraction and scattering methods or dynamic light scattering methods. path. At this time, you can indicate the value obtained by the image imaging method.

On the other hand, as a method for measuring the particle size of the fluorine resin in the non-aqueous dispersion, the volume-based average measured by the laser diffraction and scattering method, dynamic light scattering method, image imaging method, etc. can be used Particle size (50% volume diameter, median diameter).

Examples of the above-mentioned particle size measuring device include the dynamic light scattering method of FPAR-1000 (manufactured by Otsuka Electronics Co., Ltd.), or the laser diffraction and scattering method of Microtrac (manufactured by Nikkiso Co., Ltd.), or Image imaging method of Mac-View (manufactured by MOUNTECH Co., Ltd.), etc.

In the method of the present invention, the fine powder of the fluorine resin is preferably contained in an amount of 5 to 70% by mass, and more preferably 10 to 60% by mass relative to the total amount of the non-aqueous dispersion. When the content is less than 5% by mass, the amount of solvent is too large and it is not economical in manufacturing or transportation. When mixing with thermosetting resin solutions and other materials, problems caused by the large amount of solvents occur, such as the removal of solvents. Bad conditions such as time-consuming changes. On the other hand, when it exceeds 70% by mass, the viscosity becomes very large, and it is extremely difficult to maintain a fluid state.

As the non-aqueous solvent used in the non-aqueous dispersion of the method of the present invention, for example, a group selected from the group consisting of γ-butyrolactone, acetone, methyl ethyl ketone, hexane, heptane, octane, 2-heptanone, cyclic Heptanone, cyclohexanone, cyclohexane, methylcyclohexane, ethylcyclohexane, methyl n-amyl ketone, methyl isobutyl ketone, methyl isoamyl ketone, ethylene glycol, diethyl Glycol, propylene glycol, dipropylene glycol, ethylene glycol monoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monoacetate, diethylene two Alcohol diethyl ether, propylene glycol monoacetate, dipropylene glycol monoacetate, propylene glycol diacetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ring Hexyl acetate, ethyl 3-ethoxypropionate, dioxane, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl pyruvate, pyruvic acid Ethyl, methyl methoxypropionate, ethyl ethoxypropionate, anisole, ethyl benzyl ether, tolyl methyl ether, diphenyl ether, dibenzyl ether, phenethyl ether, butyl Phenyl ether, benzene, ethylbenzene, diethylbenzene, pentylbenzene, cumene, toluene, xylene, cumene, mesitylene, methanol, ethanol, isopropanol, butanol, methyl monocyclic Oxypropyl ether, ethyl monoglycidyl ether, butyl monoglycidyl ether, phenyl monoglycidyl ether, methyldiglycidyl ether, ethyldiglycidyl ether, Butyl diglycidyl ether, phenyl diglycidyl ether, methylphenol monoglycidyl ether, ethylphenol monoglycidyl ether, butylphenol monoglycidyl ether, mineral oil Refined, 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate, 4-vinylpyridine, N-methyl-2-pyrrolidone, 2-ethylhexyl acrylate, 2-hydroxyethyl methacrylate, methyl Hydroxypropyl acrylate, glycidyl methacrylate, neopentyl glycol diacrylate, hexanediol diacrylate, trimethylolpropane triacrylate, methacrylate, methyl methacrylate, benzene Ethylene, perfluorocarbon, hydrofluoroether, hydrochlorofluorocarbon, hydrofluorocarbon, perfluoropolyether, N,N-dimethylformamide, N,N-dimethylacetamide, dioxolane , Cyclohexanol acetate, dipropylene glycol dimethyl ether, propylene glycol diacetate, dipropylene glycol methyl n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate , 1,3-butanediol diacetate, 1,6-hexanediol diacetate, and various silicone oils are one type of solvent, including two or more of these solvents. Among these solvents, it is preferable to vary with the type of resin used, and examples include methyl ethyl ketone, cyclohexanone, toluene, xylene, N-methyl-2-pyrrolidone, and N ,N-dimethylformamide, N,N-dimethylacetamide, dioxolane.

In the method of the present invention, the above-mentioned solvent is mainly used, but it may be used in combination with other solvents, or other solvents may be used, and a suitable one may be selected according to the application (various resin materials for circuit boards) and the like. Furthermore, according to the polarity of the solvent used, it is considered that the compatibility with water is high. However, if the water content is large, the dispersibility of the fluorine resin particles in the solvent will be hindered, and the viscosity will increase or the particles will agglomerate. In the method of the present invention, the water content of the non-aqueous solvent used by the Karl Fisher method is preferably 6000 ppm or less [0≦water content≦6000 ppm]. In the present invention (including the examples described later), the water content of the Karl Fischer method is measured in accordance with JIS K0068:2001, and can be measured by, for example, MCU-610 (manufactured by Kyoto Electronics Industry Co., Ltd.). By making the water content in the solvent 6000 ppm or less, it is possible to further suppress aggregation when the resin solution is mixed with the fluororesin particle dispersion, and it is more preferably 5000 ppm or less, particularly preferably 3000 ppm or less, and particularly preferably 2500 ppm or less. In addition, as the adjustment of the above-mentioned water content, a dehydration method of a solvent such as a generally used non-aqueous solvent can be used. For example, a molecular sieve can be used.

In addition, the non-aqueous dispersion of the fluorine resin used in the method of the present invention has an average particle size of the dispersion of the aforementioned fluorine resin in the non-aqueous dispersion from the perspective of production and after mixing the thermosetting resin solution It is preferably 1 μm or less, and the viscosity at a temperature of 25° C. and a shear rate of 19.2/s is preferably 300 mPa·s or less, more preferably 200 mPa·s or less. The average particle size and viscosity after dispersion can be adjusted by appropriately combining the types of fluorine resin particles used, the amounts of non-aqueous solvents, etc., and using appropriate mixing means. The non-aqueous dispersion of the fluorine-based resin used in the method of the present invention thus constituted is obtained by combining at least a fine powder of a fluorine-based resin and a non-aqueous solvent, etc., and the above-mentioned appropriate means, etc., to obtain a fine particle size and A non-aqueous dispersion of fluorine resin that has low viscosity, excellent storage stability, and does not aggregate fluorine resin particles when mixed with various thermosetting resin solutions.

<Resin composition containing thermosetting resin> Examples of the resin composition used in the method of the present invention include those containing at least a thermosetting resin. As usable thermosetting resins, for example, epoxy resins, polyimide resins, polyimide resins, three resins, phenol resins, melamine resins, polyester resins, cyanate ester resins, double Maleimide resins and modified resins of these resins. These resins may be used alone or in combination of two or more. These resins are used as the base resin of the thermosetting resin composition, and they can be used without particular limitation as long as they are suitable for insulation or adhesiveness in electronic equipment. Preferable resin compositions include those containing at least cyanate ester resin and/or epoxy resin. These resins are especially suitable base resins for thermosetting resin compositions, and are suitable for insulation or adhesion in electronic equipment. Etc. As the cyanate ester resin that can be used in the method of the present invention, for example, at least 2-functional aliphatic cyanate ester, at least 2-functional aromatic cyanate ester, or mixtures thereof can be cited, for example, Produced by 1,3,5-tricyanoxybenzene, 1,3-dicyanooxynaphthalene, 1,4-dicyanooxynaphthalene, 1,6-dicyanooxynaphthalene, 1,8-dicyanooxynaphthalene, At least one polyfunctional cyanate polymer selected from oxynaphthalene, 2,6-dicyanoxynaphthalene and 2,7 dicyanoxynaphthalene, bisphenol A cyanate resin or among these Those with hydrogen, bisphenol F type cyanate resin or those with hydrogen added, 6F bisphenol A dicyanate resin, bisphenol E type dicyanate resin, tetramethyl bisphenol F two At least one of cyanate resin, bisphenol M dicyanate resin, dicyclopentadiene bisphenol dicyanate resin, cyanate novolak resin, etc. In addition, commercially available products of these cyanate ester resins can also be used.

Examples of usable epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, phenol novolac type epoxy resins, tertiary butylcatechol type epoxy resins, and naphthalene type epoxy resins. Oxygen resin, naphthyl ether type epoxy resin, glycidyl amine type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, alicyclic ring Oxygen resin, heterocyclic epoxy resin, spiro ring-containing epoxy resin, cyclohexanedimethanol type epoxy resin, trimethylol type epoxy resin, halogenated epoxy resin, etc. One type of these epoxy resins may be used, or two or more types may be used in combination. The epoxy resin usable in the method of the present invention is not limited to the above-mentioned resin as long as it has one or more epoxy groups in one molecule, but it is preferably bisphenol A, hydrogenated bisphenol A, cresol novolac and the like. In the method of the present invention, the above-mentioned cyanate ester resin and epoxy resin may be used alone or in combination, and when used in combination, the mass ratio may be in the range of 1:10-10:1.

When the above-mentioned cyanate ester resin and epoxy resin are used in the method of the present invention, active ester compounds can also be used as additives from the viewpoints of reactivity, curability, and moldability. The active ester compound that can be used is generally a compound having two or more active ester groups in one molecule, and examples thereof include carboxylic acid compounds, phenol compounds, or naphthol compounds. Examples of carboxylic acid compounds include acetic acid, benzoic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methyl Alkylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-Dihydroxynaphthalene, dihydroxydiphenylketone, trihydroxydiphenylketone, tetrahydroxydiphenylketone, phloroglucinol, benzenetriol, dicyclopentadienyl diphenol, phenol novolac Wait. One type of these active ester compounds may be used, or two or more types may be used in combination. As a commercially available active ester compound, EXB-9451, EXB-9460, HPC-8000-65T (made by DIC Co., Ltd.), DC808, YLH1030 (made by Nippon Epoxy Co., Ltd.), etc. are mentioned, for example. The usage amount of these active ester compounds can be determined according to the type of the base resin of the thermosetting resin composition used and the active ester compound used. Furthermore, among the aforementioned active ester compounds, an active ester compound hardening accelerator can be used as necessary. As the active ester compound hardening accelerator, an organometallic salt or organometallic complex is used, for example, an organometallic salt or organometallic complex containing iron, copper, zinc, cobalt, nickel, manganese, tin, etc. is used. Specifically, the aforementioned cyanate ester curing accelerators include manganese naphthenate, iron naphthenate, copper naphthenate, zinc naphthenate, cobalt naphthenate, iron octoate, copper octoate, zinc octoate, and cobalt octoate. Organometallic salts such as lead acetone, cobalt acetone and other organometallic complexes. These active ester compound hardening accelerators are based on the concentration of the metal. From the viewpoints of reactivity, hardenability, and formability, it can be 0.05-5 parts by mass relative to 100 parts by mass of the resin used above, preferably It is contained in 0.1 to 3 parts by mass.

In addition, when the above-mentioned epoxy resin is used in the method of the present invention, a curing agent may be used as an additive from the viewpoint of reactivity, curability, and moldability. Usable hardeners include, for example, ethylene diamine, ethylene pentamine, hexamethylene diamine, dimer acid modified ethylene diamine, N-ethylamino piper 𠯤, isophorone two Aliphatic amines such as amines, m-phenylenediamine, p-phenylenediamine, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 4,4'-diamine Aromatic amines such as aminodiphenylmethane, 4,4'-diaminodiphenyl ether, mercaptopropionates, mercaptans such as terminal mercapto compounds of epoxy resins, polyazelaic anhydride, methyl alcohol, etc. Tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, Alicyclic anhydrides such as camphor-2,3-dicarboxylic acid anhydride, methyl-5-norbornene-2,3-dicarboxylic acid anhydride, methyl-norbornane-2,3-dicarboxylic acid anhydride, Phthalic anhydride, trimellitic anhydride, pyromellitic anhydride and other aromatic anhydrides, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole and other imidazoles and their salts, The above-mentioned aliphatic amines, aromatic amines, and/or amine adducts obtained by the reaction of imidazoles with epoxy resins, hydrazines such as dihydrazine adipate, dimethylbenzylamine At least one of tertiary amines such as 1,8-diazabicyclo[5.4.0]undecene-7, organic phosphines such as triphenylphosphine, and dicyandiamine. The amount of these hardeners used is determined according to the epoxy resin used and the type of hardener used. In the resin composition of the method of the present invention, inorganic fillers, thermoplastic resin components, rubber components, flame retardants, colorants, tackifiers, defoamers, leveling agents, coupling agents, and adhesion can also be used in combination. It is a material generally used in thermosetting resin compositions for electronic devices, such as properties-imparting materials.

In the method of the present invention, the total resin concentration of the thermosetting resin and the like necessary for the final thermosetting resin composition of the fluorine-containing resin is adjusted, and as described later, the non-aqueous dispersion of the fluorine-containing resin is mixed with the heat-containing In the step of the resin composition of the curable resin, the fine powder of the fluorine-based resin can be made to exist uniformly without agglomeration by passing through a step including a treatment that does not bring foreign matter or air bubbles into the next step, and becomes a more dielectric The constant and the dielectric tangent are low, and there are no foreign objects that can hinder the wiring pattern or the adhesion between layers, and can exhibit excellent characteristics. The content of the non-aqueous dispersion of fluororesin in the above mixing step varies with the amount of fine powder of fluororesin such as PTFE and the amount of non-aqueous solvent contained in the dispersion, and varies with the thermosetting resin, etc. The use of the composition of the resin composition varies. The non-aqueous solvent in the resin composition is finally prepared by the composition containing the thermosetting resin, and then removed during curing. Therefore, relative to 100 parts by mass of the resin, fluorine such as PTFE is used. The content of the fine powder of the resin is preferably a dispersion adjusted so that it is finally preferably 1 to 120 parts by mass, more preferably 5 to 100 parts by mass. The content of the fine powder of fluorine-based resin such as PTFE is set to 1 part by mass or more with respect to 100 parts by mass of the resin, so that the electrical characteristics of low specific permittivity and low dielectric tangent can be exhibited. On the other hand, by By setting it as 120 parts by mass or less, the adhesiveness and heat resistance of the thermosetting resin are not impaired, and the effects of the present invention can be further exhibited.

<Contains steps that do not bring foreign matter or bubbles to the next step> In the method of the present invention, in the step of mixing the non-aqueous dispersion of the fluorine-based resin and the resin composition (thermosetting resin solution) containing the thermosetting resin, it is considered that no foreign matter or air bubbles are brought into the next step. The process of the process of the process, in order to suppress the foreign matter, the following method of homogenization during mixing, the method of redispersion, and the method of filtration can be mentioned. These can be carried out singly or in combination of two or more kinds. In addition, for suppressing bubbles, there can be mentioned the method of using a rotation/revolution mixer during mixing and/or the method of combining with decompression, the method of using a vacuum pump, the method of using a deaerator, and the method of using an ultrasonic mixer. , These systems can be carried out singly or in combination of two or more.

In the method of the present invention, the method of mixing the above-prepared non-aqueous dispersion of fluorine-based resin and the above-prepared resin composition containing thermosetting resin to achieve homogenization is to mix fluorine-based resin fine powder This is a mixing method where the interface between the non-aqueous dispersion (A) and the thermosetting resin solution (B) disappears within 3 seconds and is homogenized within 1 minute. The so-called "interface" is defined as: the content of B in phase A in its vicinity is less than 5% by mass, and the content of A in phase B is less than 5% by mass. In addition, the so-called "homogenization" is defined as a state in which there is no unevenness in the mixture of (A) and (B) above. In addition to visual inspection, there are multiple samples collected from any place, such as from a mixing tank. Samples are collected at three points of the upper, middle, and lower troughs, and no significant difference can be seen during analysis. As a method for achieving this homogenization, for example, as long as the liquid surface is flowing at a high speed by the stirring blade (B), dripping (A), or inserting a nozzle or a tube into the liquid flowing at a high speed (B), and injecting it from the inside. (A), or for (B) in high-speed liquid delivery piping, make (A) converge, or spray (A) to the liquid surface of flowing (B) through a nozzle that turns (A) into fine droplets, or The method of using a two-fluid nozzle to mix (A) and (B), or to make the interface disappear within 3 seconds, is not limited to the aforementioned method. At this time, (B) can be added to (A), but when there is a viscosity difference, it is preferable to add a low-viscosity liquid to a high-viscosity liquid. Since there is a slight unevenness after the interface disappears, it is necessary to provide a processing time for fully homogenizing the mixture in the work. If a part of the liquid existing at a certain point in the work passes through a step near the same point as one rotation, it is preferable to perform homogenization of 10 rotations or more. It is more preferably 30 rotations or more, particularly preferably 50 rotations or more, and ideally 100 rotations or more in homogenization. In addition, in order to reduce the viscosity of (B), it is also effective for homogenization to temporarily heat the product in a range where there is no problem in quality. 1 The conditions of rotation can be defined by sinking and stirring undissolved solids in a transparent liquid with the same viscosity in advance.

In the method of the present invention, the redispersion method is to mix the above-mentioned (A) and (B) composition. Since the fine powder of the fluorine-based resin settles for a long period of time, it becomes the cause of unevenness or foreign matter. It is a method of stirring or recirculating it to return to a uniform state again. This redispersion method may be performed intermittently, or may be performed continuously when the thermosetting resin composition is supplied to the next step. At that time, in order to avoid the entry of bubbles, it is better to control the minimum stirring or circulation rate. It can also be combined with reduced pressure, and it is also effective to fill the work with a thermosetting composition containing fluorine-containing resin particles to become completely gas-free and redisperse it.

In the method of the present invention, the filtering method is a method of filtering the mixture of (A) and (B) that suppresses foreign matter by the above-mentioned mixing method. Install a filter in the piping that is supplied to the next step to prevent foreign matter from entering the next step. A filter (for example, a pore size of 1 to 50 μm) can be connected to the tank for storing the mixture and circulated to remove coarse foreign matter. By doing so, most of the foreign matter can be circulated and removed, the clogging of the filter on the piping connected to the next step can be suppressed, and the effect of stabilizing the flow control can be obtained. Examples of filters include depth filters, pleated filters, leaf filters, bag filters, wound filters, sintered filters, etc. with a pore diameter of 1-50 μm. Examples of membranes include poly Films or non-woven fabrics of propylene, polyethylene, PTFE, polyvinylidene fluoride, polyether, nylon, glass fiber, cotton, etc. In addition, in order to monitor clogging of the filter, it is preferable to use a pressure gauge or a flow meter in combination. Furthermore, in order to correspond to continuous production, the filters can be arranged in parallel, and it is better to directly arrange filters with different pore diameters in series in multiple stages to prevent clogging without the need to exchange filters. In either case of the above-mentioned parallel connection and series connection, the differential pressure between the primary pressure and the secondary pressure of each filter is also preferably managed at 0.1 MPa or less, more preferably 0.08 MPa or less, and particularly preferably 0.05 MPa or less.

In the method of the present invention, as a form of defoaming, a method of defoaming using a rotation/revolution mixer can be cited. The mixer of the mixing tank can remove bubbles from the composition by two rotations (rotation and revolution). In addition, a pressure reducing device or a vacuum device can also be combined therein. As a rotating and revolving mixer, commercially available mixers can be used, and Mazerustar KK-V series (manufactured by KURABO), a planetary mixing and defoaming device with a vacuum device, and a vertical mixer manufactured by Seishin Corporation can be used for revolving and rotating. Type (PX type), etc., suitable for combining the speeds of rotation (rpm) and revolution (rpm), and by combining decompression or vacuum, the most suitable defoaming can be performed.

In the method of the present invention, as a form of defoaming, a method using a vacuum pump can be cited. The bubbles in the composition can be removed by evacuating the stirring tank. It is preferable to combine stirring to the extent that the upper gas phase is not involved. The degree of vacuum is preferably higher than -0.090 MPa. Furthermore, in the method of the present invention, as a form of performing defoaming, a method using a defoaming machine can be cited. When the foam grows and is difficult to handle among the above-mentioned vacuum pumps, a commercially available deaerator can be used. For example, Mixter manufactured by Mixter Industrial Co., Ltd. can be used. The method of directly thinning the composition in a liquid state and introducing it under vacuum to remove bubbles is also effective. Bubble-Burster manufactured by Ashizawa Finetech can be used. A system that uses a filter to separate bubbles can also be used. These systems can be used together for capacity or cost optimization. Furthermore, in the method of the present invention, as a form of defoaming, there is a method of using an ultrasonic mixer. By applying ultrasonic waves to the composition and shaking it finely, bubbles can be removed. The degree of vacuum is preferably higher than -0.090 MPa. In the method of the present invention, the above-mentioned foreign matter suppression and defoaming methods can be combined as required, and can also be carried out in parallel at the same time. When the viscosity of the resin solution is low, even if no special defoaming treatment is performed, the bubbles will run away in a short time, so a certain time of standing still can be used as a defoaming step. In addition, when mixing is filled with a thermosetting composition containing fluorine-containing resin particles during mixing, and mixing is performed in a completely gas-free state, the mixing step itself can be treated as a defoaming step.

FIG. 1 is a schematic diagram showing an example of the embodiment of the manufacturing step of the method of the present invention, and FIG. 2 and FIG. 3 each show a schematic diagram of another example of the embodiment of the manufacturing step of the method of the present invention. 2 and FIG. 3, the same reference numerals are attached to those in common with FIG. 1, and the description thereof will be omitted. In Fig. 1, the X system shows all the manufacturing steps of the method of the present invention. The non-aqueous dispersion (A) of the fluorine resin prepared above and the thermosetting resin prepared above are put into a blender (mixing tank). The resin composition [thermosetting resin solution] (B). This mixing step is a step including processing that does not bring foreign matter or bubbles into the next step. The "next step" in the method of the present invention refers to those that include various steps depending on the application of the thermosetting resin composition of the fluorine-containing resin. Drying step, hardening step, laminating step, manufacturing 3-layer FCCL, or in the use of FCCL polyimide substrate, manufacturing 2-layer FCCL through polyamide coating step, drying step, and curing step.

In Figure 1, 10 is a closed tank with a mixer, 11 is a valve, 12 is a vacuum pump installed in the mixer, 13 is a vacuum gauge, 14 is a compressed air supply device, 15 is a diaphragm pump, 16a, 16b are valves, and 17 is a delivery device. Liquid pump, 18 is a pressure gauge, 19 is a filter device, and 20 is a coating machine. In addition, a to g are each pipe (pipeline) connecting each device. In this embodiment, the non-aqueous dispersion (A) of the fluorine resin prepared above and the resin composition containing the thermosetting resin prepared above [thermosetting resin solution] are put into the closed tank 10 with a stirrer. (B). The closed tank 10 with agitator is connected with the vacuum pump 12 and the compressed air supply device 14. Therefore, by appropriately combining these devices, the mixing (stirring) of (A) and (B) can be carried out at the same time. Removal (defoaming) while achieving homogenization. In addition, when the mixed liquid in the closed tank 10 with a stirrer is sent to the next step and waits for a certain period of time, it may be stirred or circulated to return to a uniform state again. In addition, it is also possible to defoam the contents by using a rotating and revolving mixer and a vacuum device. In the present embodiment, the compressed air supply device of 14 reduces the pressure of each pipe a to e to prevent air bubbles. As a countermeasure against foreign matter, after mixing, a filtration system composed of a liquid feeding pump 17, a pressure gauge 18, and a filter 19 is provided. Therefore, no foreign matter is generated before the liquid is fed to the coater 20 in the next step. This filtration system consisting of the liquid feeding pump 17, the pressure gauge 18, and the filter 19 is not only connected to the coating machine 20, but also can be connected to the attached pipe g by the valves 21a and 21b branching the pipe f. The airtight tank 10 of the mixer performs circulating filtration.

In addition, as shown in Fig. 2, it is also possible to remove foreign matter in advance with a filtration system that independently serves as a circulating filtration without branching. The symbol 16c in the figure is a valve, and h and i are respective pipes (pipelines) connecting the respective devices. This is a filtration system consisting of a liquid feeding pump 17, a pressure gauge 18, and a filter 19, which serves as a separate circulating filter. In addition to being connected to the coating machine 20, it can also be connected to the enclosed tank 10 with a mixer or with a mixer. The closed tank 10 is connected to the piping, etc., for circulating filtration. Furthermore, as shown in FIG. 3, the system is integrated with the filter system that finally sends the liquid to the coating machine 20, and the filter 19b removes most of the foreign matter, and the filter 19a can completely remove the remaining foreign matter. , Parallel users are also effective. Symbols j and k shown in the figure are pipes (pipelines) connecting each device. This system includes a liquid feeding pump 17b, a pressure gauge 18b, and a filter 19b serving as circulating filtration, and a liquid feeding pump 17a, a pressure gauge 18a, and a filter 19a that ultimately prevent foreign matter from being mixed into the coater 20. In such a case, since clogging of the filter 19a connected to the coating machine is reduced, it is effective in a device in which the stability of the flow rate of the coating machine has a large influence on the quality of coating. In addition, the liquid feeding to the coating machine 20 while performing circulating filtration is also effective for increasing the processing rate.

In each of the above-mentioned embodiments, the mixing step includes a configuration that does not bring foreign matter or bubbles into the next step. By this, even though the fine powder of the fluorine-based resin is mixed, the fluorine-containing resin is also mixed in the fluorine-containing resin. Hardly any coarse foreign matter or air bubbles are visible in the thermosetting resin, and there is no aggregation of fluorine-based resin fine powder, which can achieve low dielectric constant and low dielectric tangent while suppressing hindering the wiring pattern. Or the adhesion of foreign matter between layers, so it can be used for thermal curing of fluorine-containing resins such as insulating layers for multilayer printed wiring boards, adhesives for circuit boards, laminates for circuit boards, cover films, prepregs, etc. Resin composition.

<Preferred form of non-aqueous dispersion of fluorine-based resin> The non-aqueous dispersion system of fluorine-based resin used in the method of the present invention is as described above. Fluorine-based and lipophilic-based fluorine-based additives and/or compounds represented by the following formula (I).

In the non-aqueous dispersion of the method of the present invention, the usable fluorine-based additive is not particularly limited as long as it has at least a fluorine-containing group and a lipophilic group, and may additionally contain a hydrophilic group. By using a fluorine-based additive having at least a fluorine-containing group and a lipophilic group, the surface tension of the non-aqueous solvent used as the dispersion medium can be reduced, the wettability of the fluorine-based resin fine powder surface can be improved, and the fluorine-based resin’s performance can be improved. The dispersibility of the fine powder, while the fluorine-containing group is adsorbed on the surface of the fine powder of the fluorine-based resin, the lipophilic group is extended in the non-aqueous solvent that becomes the dispersion medium, and the steric barrier of the lipophilic group prevents the fluorine-based resin from being degraded. The agglomeration of fine powder further improves dispersion stability.

Examples of fluorine-containing groups include perfluoroalkyl groups, perfluoroalkenyl groups, and the like. Examples of lipophilic groups include one or more of alkyl groups, phenyl groups, siloxyalkyl groups, etc., as hydrophilic groups. Examples of the functional group include one or two or more of ethylene oxide, amino, ketone, carboxyl, and sulfide groups. As fluorine-based additives that can be specifically used, Surflon series (manufactured by AGC Seimi Chemical Co., Ltd.) such as Surflon S-611 containing perfluoroalkyl groups, Megafac F-555, Megafac F-558, Megafac F-563, etc. can be used. Series (manufactured by DIC), Unidyne series such as Unidyne DS-403N (manufactured by Daikin Industry Co., Ltd.), Floren FD-420 (manufactured by Kyoeisha Chemical), Ftergent 610FM, FTX-218, 215M, 710FM, 730LM, etc. (NEOS company system) and so on. These fluorine-based additives are appropriately selected according to the types of the fluorine-based resin fine powder and the non-aqueous solvent used, and may be one type or a combination of two or more types.

The content of the aforementioned fluorine-based additive is 0.1-50% by mass relative to the mass of the fine powder of the fluorine-based resin, but is preferably 0.3-20% by mass, more preferably 0.5-5% by mass. Relative to the mass of the fluorine-based resin fine powder, when the content is less than 0.1% by mass, the surface of the fluorine-based resin particles cannot be sufficiently wetted in the non-aqueous solvent. On the other hand, when the content exceeds 50% by mass, the dispersion will appear. The foam becomes stronger and the efficiency of dispersion is reduced, and it is unfavorable to handle the dispersion itself or when it is mixed with resin materials afterwards. In addition, even if there is no defect such as foam, it is not economical to add a large amount of fluorine-based additives because they are expensive.

The compound system represented by the above (I) used in the method of the present invention can uniformly and stably disperse the fine powder of the fluorine resin as fine particles in the non-aqueous solvent. Its molecular structure is a ternary polymerization composed of vinyl acetal/vinyl acetate/vinyl alcohol. It has an acetal group and acetal group for the reaction of polyvinyl alcohol (PVA) with butyraldehyde (BA) and other aldehydes. The structure of groups and hydroxyl groups can be controlled in various resins by suppressing the solubility in non-aqueous solvents by changing the ratio of these three structures (the respective ratios of l, m, and n) and the type of acetal group. Chemical reactivity when a non-aqueous dispersion of fine powder of fluorine resin is added to the material.

As the compound represented by (I) above, S-LEC B series manufactured by Sekisui Chemical Industry Co., Ltd., K(KS) series, SV series, Mowital series manufactured by KURARAY, etc. can be used among commercially available products. Specifically, the trade names of Sekisui Chemical Industry Co., Ltd. can be cited; S-LEC BM-1, the same as BH-3, the same as BH-6, the same as BX-1, the same as BX-5, the same as BM-2, Same as BM-5, same BL-1, same BL-1H, same BL-2, same BL-2H, same BL-5, same BL-10, same KS-10, etc., or KURARAY (share) product name ; Mowital B14S, same B16H, same B20H, same B30H, same B45H, same BX860, same B60H, same B75H, same BL16, same B30HH, same B60HH, same B30T, same B45M, same B60T, etc., or products manufactured by EASTMAN Name: BUTVAR B-72, same as B-74, same as B-76, same as B-79, same as B-90, same as B-98, etc. These systems can be used alone or in combination of two or more. In addition, as long as it is within the range of the aforementioned fluorine-based additive and the specified addition amount, it can also be used in combination.

The content of the compound represented by (I) above is preferably 0.1-50% by mass relative to the fluorine-based resin particles. If the content of the compound is less than 0.1% by mass, the dispersion stability will deteriorate and the fluorine resin particles will easily settle, and if it exceeds 50% by mass, the viscosity will increase and fluidity of the dispersion will not be obtained. Furthermore, considering the properties of the non-aqueous dispersion of fluorine resin particles added to the thermosetting resin, etc., it is preferably 0.1-15% by mass, more preferably 0.1-10% by mass, and most preferably 0.3-5 quality%. Furthermore, in the present invention, when the above-mentioned fluorine-based additive containing at least a fluorine-containing group and a lipophilic group is used in combination with the compound represented by the above formula (I), in order to maximize the combined effect, it is preferably relative to the fluorine-based resin The mass of the fluorine-based additives is preferably 0.1-5 mass%, and the compound represented by the above formula (I) is preferably 0.1-5 mass%.

The non-aqueous dispersion of the fluorine resin used in the method of the present invention preferably further contains a polymer having a urethane structure. The non-aqueous dispersion of fluorine-based resin used in the method of the present invention suppresses the above-mentioned foreign matter and defoaming while mixing a thermosetting resin solution and a fine powder dispersion of fluorine-based resin, and at the same time suppresses unstable stability due to the dispersion system. The fluorine-based resin fine powder is agglomerated. If a dispersion of fluorine-based resin fine powder is mixed with a solution with a different composition, the components in the solution move to the dispersion phase, adsorb to the particle surface, and destroy the dispersion system. Due to the difference in the concentration of the various components, a dispersion stabilizer or The non-uniformity of the solvent causes the particles to agglomerate. The polymer with a urethane structure used in the present invention can reduce the sudden change in the composition of the dispersion by inhibiting the movement of substances during mixing, and inhibit aggregation. If the above-mentioned foreign matter suppression and defoaming are performed, It also suppresses agglomerates and can achieve dispersion and stability.

The polymer having a urethane structure used in the method of the present invention is composed of a compound having more than one urethane bond (-NH-COO-) in one molecule, Formula: R-NH-COO-R’ (In the above formula, R and R'are aliphatic, alicyclic or aromatic monovalent or multivalent organic groups, and the multivalent organic groups are further bonded to other groups with urethane bonds or Other bases). In a polymer with a urethane structure, there may be lipophilic groups and/or hydrophilic groups. In addition, these groups may be present in the main chain and/or side of the polymer with a urethane structure. More than one chain may be present in the polymer having a urethane structure. Two or more urethane bonds may be present in the polymer having a urethane structure, and the urethane bonds may be the same or different.

Examples of polymers having such a urethane structure include diisocyanates and/or triisocyanates, polyesters having hydroxyl groups at one end and/or polyesters having hydroxyl groups at both ends. Reaction product. Examples of the diisocyanates include benzene diisocyanates such as benzene-1,3-diisocyanate and benzene-1,4-diisocyanate; toluene-2,4-diisocyanate, toluene-2,5-diisocyanate, etc. Toluene diisocyanates such as isocyanate, toluene-2,6-diisocyanate, toluene-3,5-diisocyanate; 1,2-xylene-3,5-diisocyanate, 1,2-xylene-3,6 -Diisocyanate, 1,3-xylene-2,4-diisocyanate, 1,3-xylene-2,5-diisocyanate, 1,3-xylene-4,6-diisocyanate, 1,4- Other aromatic diisocyanates such as xylene diisocyanates such as xylene-2,5-diisocyanate and 1,4-xylene-2,6-diisocyanate.

In addition, examples of the above-mentioned triisocyanates include benzene-1,2,4-triisocyanate, benzene-1,2,5-triisocyanate, benzene-1,3,5-triisocyanate, and other benzene triisocyanates. ; Toluene triisocyanate such as toluene-2,3,5-triisocyanate, toluene-2,3,6-triisocyanate, toluene-2,4,5-triisocyanate, toluene-2,4,6-triisocyanate, etc. ; 1,2-xylene-3,4,5-triisocyanate, 1,2-xylene-3,4,6-triisocyanate, 1,3-xylene-2,4,5-triisocyanate, 1 ,3-xylene-2,4,6-triisocyanate, 1,3-xylene-4,5,6-triisocyanate, 1,4-xylene-2,3,5-triisocyanate, 1,4 -Xylene-2,3,6-triisocyanate and other aromatic triisocyanates such as xylene triisocyanate. These diisocyanates and triisocyanates can be used individually or in mixture of 2 or more types.

As the above-mentioned polyesters having hydroxyl groups at one end and polyesters having hydroxyl groups at both ends, particularly from the viewpoint of dispersibility, it is preferable to include -(OR ^j CO)n-(R ^j is carbon number 1 -20 alkylene, n is an integer of 2 or more) of the polyester chain compound. Specific examples of the polyester chain include polylactones such as polycaprolactone, polyvalerolactone, and polypropiolactone, polyethylene terephthalate, polybutylene terephthalate, etc. Polycondensation series polyester. Among them, from the viewpoint of heat resistance, it is preferable to include polylactones, especially polycaprolactone. Specifically, polycaprolactone having hydroxyl groups at one or both ends, polyvalerolactone having hydroxyl groups at one or both ends, polypropiolactone having hydroxyl groups at one or both ends, etc. can be cited. Polylactones having hydroxyl groups at one or both ends; polyethylene terephthalate having hydroxyl groups at one or both ends, polybutylene terephthalate having hydroxyl groups at one or both ends, etc. Polycondensation polyesters etc. having hydroxyl groups at one end or both ends. These polyesters having a hydroxyl group at one end and polyesters having a hydroxyl group at both ends can be used individually or in combination of two or more types.

As the polymer having a urethane structure in the method of the present invention, an aromatic diisocyanate and a polylactone having a hydroxyl group at one end and/or a polylactone having a hydroxyl group at both ends are preferred. The reaction product is particularly preferably a reaction product of toluene diisocyanate and polycaprolactone having hydroxyl groups at one end and/or polycaprolactone having hydroxyl groups at both ends. In addition, the polymer having a urethane structure is preferably one that does not have an acidic functional group from the viewpoint of dispersibility. As an acidic functional group, a carboxyl group, a sulfo group, a phosphoric acid group, etc. are mentioned, for example, and a carboxyl group is typical. Furthermore, from the viewpoint of heat resistance, the polymer having a urethane structure preferably does not contain a polyether chain that is easily cut by heating. The polyether chain here refers to a structure represented by -(OR ⁱ )n- (R ⁱ is an alkylene group having 1 to 10 carbon atoms, and n is an integer of 2 or more). Specifically, -(O-CH ₂ CH ₂ )n-, -(O-CH ₂ CH ₂ CH ₂ )n-, -(O-CH ₂ CH ₂ CH ₂ CH ₂ )n-,- (O-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ )n-, -(O-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH 2 )n-.

As the polymer having a urethane structure used in the method of the present invention, commercially available products include the DISPERBYK series manufactured by BYK Chemical Company, the Efka series manufactured by BASF Company, the Burnock series manufactured by DIC Company, and the Soluspass series manufactured by LUBRIZOL Company. Specifically, from the point of view of heat resistance, electrical reliability, and dispersion, BYK chemical products: DISPERBYK-161, same 162, same 163, same 164, same 167, same 168, same 170, Same as 174, same 180, same 182, same 184, same 185, same 2163, same 2164, etc., or BASF system: Efka PU4063, etc., or DIC system: Burnock 16-411, same as 16-416, same as 16-472, same DF-402, same DF-407, same ENL-659, etc., or made by LUBRIZOL: Soluspass 71000, same 74000, same 75500, same 76400, same 76500, same 79000, etc. The weight average molecular weight (Mw) of the polymer having a urethane structure in the method of the present invention is usually 5,000 to 50,000, preferably 7,000 to 20,000. The above-mentioned polymer system having a urethane structure can be used singly or as a mixture of two or more kinds.

The content of the polymer having a urethane structure is preferably 0.1 to 30% by mass relative to the fine powder of the fluorine-based resin. If the content of this compound is less than 0.1% by mass, the aggregation inhibitory effect will not be exhibited. Even if it exceeds 30% by mass, the aggregation inhibitory effect will decrease, which is not only excessive but also uneconomical. Furthermore, considering the properties of a non-aqueous dispersion of fine powder of fluorine-based resin added to thermosetting resin, etc., it is preferably 0.1-20% by mass, more preferably 0.1-15% by mass, and most preferably 0.3 ～10% by mass.

In the non-aqueous dispersion of fluorine-based resin particles in the method of the present invention, in addition to the fine powder of the fluorine-based resin and the non-aqueous solvent, a surfactant or a non-aqueous solvent can be used within the range that does not impair the effects of the present invention. The dispersant may be combined with the above-mentioned fluorine-based additives, the compound represented by the above-mentioned formula (I), and a polymer having a urethane structure, and other surfactants or dispersants may be used. For example, as usable surfactants or dispersants, whether fluorine or non-fluorine, nonionic, anionic, cationic, etc. surfactants or dispersants, nonionic, anionic, and cationic can be mentioned. Such as polymer surfactants or polymer dispersants, etc., but are not limited to these and can be used.

The non-aqueous dispersion of the fluorine-based resin of the present invention, which is the above-mentioned preferred form, is obtained by dispersing the aforementioned fluorine-based resin in the non-aqueous dispersion in terms of production and after mixing the thermosetting resin solution The average particle size is preferably 1 μm or less, and the viscosity at a temperature of 25° C. and a shear rate of 19.2/s is preferably 300 mPa·s or less, preferably 200 mPa·s or less. The average particle size and viscosity of these dispersions can be determined by appropriate combinations of the types of fluorine-based resin particles used, fluorine-based additives, the compound represented by the above formula (I), polymers with a urethane structure, and non-volatile resins. The respective amounts of water-based solvents, etc., are adjusted using appropriate mixing means, etc. The non-aqueous dispersion of the fluorine resin in this preferred form is obtained by containing at least: fluorine resin particles, at least a fluorine-containing group and a lipophilic group, and/or a fluorine-based additive represented by the above-mentioned formula (I) Compounds, polymers with urethane structure and non-aqueous solvents, with fine particle size, low viscosity, and excellent storage stability. When mixing with various thermosetting resin solutions, that is, when mixing the above-mentioned fluorine resins In the step of the non-aqueous dispersion and the above-mentioned resin composition (thermosetting resin solution) containing a thermosetting resin, it can be more advanced by going through a step including a treatment that does not bring foreign matter or air bubbles into the next step. The effect of the present invention can be exerted.

[Thermo-curable resin cured product of fluorine-containing resin] The method of the present invention is a method for producing a thermosetting resin composition containing a fluorine-based resin, wherein the thermosetting resin composition at least contains: the above-mentioned non-aqueous dispersion of a fluorine-based resin containing at least a fluorine-based resin fine powder and a non-aqueous solvent , And a resin composition containing a thermosetting resin; in the above step of mixing the non-aqueous dispersion of the fluorine resin and the resin composition containing the thermosetting resin, by including the inclusion of no foreign matter or air bubbles Step to the next step, and the obtained thermosetting resin composition of the fluorine-containing resin can be molded and cured by the same method as the well-known thermosetting resin composition such as epoxy resin composition. Become a hardened object. The molding method and curing method used can be the same as those of the well-known thermosetting resin composition such as epoxy resin composition. The method inherent in the thermosetting resin composition of the fluorine-containing resin of the present invention is not required, and there is nothing special. The limit. The cured product obtained by curing the thermosetting resin composition of the fluorine-containing resin obtained by the method of the present invention can take the form of a laminate, a molded product, an adhesive, a coating film, a film, and the like. The resulting thermosetting resin composition of the fluorine-containing resin and its cured product are processed in the above-mentioned manufacturing steps including processing steps that do not bring foreign matter or air bubbles into the next step, so the thermosetting of epoxy resins and the like are not damaged The resin has excellent adhesion or heat resistance, low specific permittivity and low dielectric tangent. Moreover, in the non-aqueous dispersion of fluorine resin, it contains at least a fluorine-containing group and a lipophilic group. The fluorine-based additive and/or the compound represented by the following formula (I), and/or the above-mentioned polymer having a polyurethane structure can further suppress foreign matter caused by the agglomeration of the fine powder of the fluorine-based resin Therefore, it is suitable for electronic substrate materials or insulating materials, adhesive materials, etc., such as sealing materials for electronic parts, copper clad laminates, insulating coatings, composite materials, insulating adhesives, etc., especially suitable for multilayer printing of electronic equipment Formation of insulating layers of wiring boards, laminates for circuit boards, cover films, prepregs, etc. [Example]

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. In addition, the present invention is not limited by the following examples and the like.

[Examples 1a to 3b, Comparative Examples 1a to 3b] [Preparation of non-aqueous dispersion of fluorine-based resin] Using the blending formulation shown in Table 1 below, non-aqueous dispersions of each fluorine-based resin were prepared. In the above preparation, the fluorine-based additives, the compound represented by formula (I), and the polymer having a urethane structure are mixed thoroughly in a non-aqueous solvent, and after dissolution, PTFE fine powder is added as the fluorine-based resin The fine powder of the powder is stirred and mixed. After that, use a disperser: Dyno-Mill (horizontal mill) Multi Lab to disperse the resulting PTFE mixture under the conditions of dispersing conditions: zirconia ϕ 0.3mm, filling rate 50%, peripheral speed 10m/s After 1 hour of batch processing, the beads were separated, and the average particle size (scattering intensity) of PTFE in the non-aqueous dispersion of each fluororesin was measured by the dynamic light scattering method of FPAR-1000 (manufactured by Otsuka Electronics Co., Ltd.) The average particle size analyzed by the cumulant method in the distribution). In addition, the viscosity of the non-aqueous dispersion (25°C) of each fluorine-based resin was measured using an E-type viscometer at a shear rate of 19.2/s. The following Table 1 shows the blending formula of the non-aqueous dispersion of each fluororesin, and the average particle size of PTFE in the resulting dispersion. In addition, the water content of the non-aqueous dispersion of each fluorine resin was measured by the Karl Fisher method, and the result was confirmed to be in the range of 400 to 2500 ppm.

[Preparation of thermosetting resin solution (mixing)] Using the obtained non-aqueous dispersions of the above-mentioned fluorine resins, the blending formula shown in Table 1 below (modified phenol novolak type epoxy resin: 20% by mass toluene solution, modified polyamide resin solution: 15% by mass N-methyl-2-pyrrolidone solution) to prepare a thermosetting resin solution (mixed) of fluorine-containing resin. In the mixing of each embodiment, the following method was used to prepare the mixture through a step including a process that does not bring foreign matter or bubbles to the next step.

(Examples 1a and 1b) According to Figure 1, in accordance with the blending formula in Table 1, in a closed tank with a mixer (LZB33-4S manufactured by Chuo Rika Co., Ltd.), a resin composition containing a thermosetting resin was injected, and the mixer The number of stirring rotations at which the liquid surface flows at a high speed makes it flow at a high speed, and a non-aqueous dispersion of fluorine-based resin is dripped from the upper part. At the time of dripping, the two liquid systems are instantly integrated, and the interface formation is not visible at least by visual inspection. After the addition of the non-aqueous dispersion of the fluorine-based resin is completed, the tank is sealed, and the sealed tank with a stirrer is depressurized to -0.095MPa, and the time of 100 rotations of the content liquid is homogenized as described above. After homogenization, the number of rotations of the mixer is reduced, the valve 11 and the valve 16a are opened, and the mixture in the closed tank is circulated by the diaphragm pump 15. At this time, it is prepared so that the vacuum degree is maintained at -0.095 MPa. This defoaming process is continued until the content returned from the pipe b to the closed tank becomes bubble-free. After the defoaming treatment, the airtight tank was returned to atmospheric pressure, the valve 16a was opened, and the mixture was passed through a filtration system composed of a liquid feeding pump 17, a pressure gauge 18, and a filter 19 with a ^{pore size of 5 μm and a filtration area of 0.22 m 2} The liquid is sent to the next step, and no foreign matter or bubbles are brought into the next step. The air pressure on the day of the experiment was 1030 hPa.

(Examples 2a and 2b) Except that the filtration system shown in FIG. 2 is used as the above-mentioned circulating filter, and before the mixture is fed to the next step, a 5-rotation circulating filter is carried out, similarly to the above-mentioned Examples 1a and 1b. Or the bubbles are brought into the next step of processing.

(Examples 3a and 3b) Except that the degree of vacuum at the time of degassing was set to -0.080 MPa, in the same manner as in Examples 1a and 1b, treatment was performed to prevent foreign matter or air bubbles from being brought into the next step.

(Comparative Examples 1a and 1b) According to Fig. 1, only when the non-aqueous dispersion of the fluorine-based resin is added, mixing is performed while maintaining the state where the interface between the two liquids is formed for about 1 minute. According to the blending formula of Table 1, the treatment was carried out in the same manner as in Example 1.

(Comparative Examples 2a and 2b) Except that defoaming was not carried out, the treatment was carried out in the same manner as in Examples 1a and 1b.

(Comparative Examples 3a and 3b) The treatment was performed in the same manner as in Examples 1a and 1b, except that filtration was not performed.

The mixture of the thermosetting resin solutions obtained in the foregoing Examples 1a to 3b and Comparative Examples 1a to 3b was evaluated by the following evaluation method. Evaluation method of thermosetting resin solution mixing: The thermosetting resin solutions (mixed) obtained in Examples 1a to 3b and Comparative Examples 1a to 3b were collected in a bottle and left to stand for 1 day. The amount of aggregates and the presence of foreign matter at the bottom of the bottle were evaluated using the following evaluation criteria. After 3 days, the sedimentation and separation state was evaluated by the following evaluation criteria. Furthermore, during the mixture filtration step, the following evaluation criteria were used to evaluate the liquid permeability of the filter with a pore diameter of 5 μm. The results of these are shown in Table 1. Evaluation criteria for the amount of aggregates and foreign matter: ○: No aggregates or foreign matter ×: There are aggregates or foreign matter Evaluation criteria for sedimentation separation: ○: No sedimentation and separation ×: There is sedimentation and separation Evaluation criteria of filter permeability: ○: Almost no filter exchange caused by clogging (relative to the feed volume, the filter is exchanged 0 to 1 times) △: There is filter exchange caused by clogging (relative to the feed volume, the flow volume is 1/2～1/4) ×: Filters are frequently exchanged due to clogging (relative to the feed volume, the flow rate is less than 1/4)

[Preparation of thermosetting resin cured product of fluorine-containing resin] Film formation evaluation (make a 1mil coating film on the glass and dry it at 150°C for 10 minutes, then evaluate the state of the film) The modified phenol novolac type epoxy resin was cured at 200°C for 1 hour, and the modified polyamide system was cured at 350°C for 30 minutes. The following evaluation criteria were used to evaluate the state of the cured film (bulging, pinhole, and thinning). These results are shown in Table 1 below. Evaluation criteria for bulging and pinholes: ○: No bulging or pinholes △: Slight bulging and pinholes ×: There are a lot of bulging and pinholes Thin film evaluation criteria: ○: Peelable from glass (thin film) ×: Cannot be peeled from the glass (thin film)

(Evaluation of electrical characteristics) On the entire surface of one side of the polyimide film (thickness: 25μm), use a coater to coat the mixture of the thermosetting resin solution obtained above (a fluorine-containing resin) so that the thickness after drying becomes about 25μm. The thermosetting resin composition) has a uniform thickness, and after drying at about 120°C for about 10 minutes, it is cured by heating at 180°C for 60 minutes to prepare an evaluation sample. Using each evaluation sample obtained above, the electrical characteristics (specific permittivity and permittivity tangent) were evaluated by the test method shown below. The specific permittivity and dielectric tangent are measured at 10 GHz using a vector network analyzer and resonator in accordance with the test specifications of JIS C6481-1996. In addition, the modified phenol novolak type epoxy resin cured product (resin only) has a specific dielectric constant of 3.8 and a dielectric tangent of 0.050, and the modified polyamide acid cured product (resin only) has a specific dielectric constant of 3.2, The dielectric tangent is 0.020. These results are shown in Table 1 below.

As can be seen from the results in Table 1 above, compared with Comparative Examples 1a to 3b outside the scope of the present invention, Examples 1a to 3b supporting the method of the present invention are in the mixing step, by not bringing foreign matter or bubbles into the mixing step. Into the next step of processing, it is confirmed that a thermosetting resin composition of fluorine-containing resin can be produced. Although it is mixed with fine powder of fluorine-based resin, it can almost be seen in hardened thermosetting resin of fluorine-containing resin. There are no coarse foreign matter or bubbles, and there is no aggregation of fluorine-based resin fine powder. It can achieve low dielectric constant and low dielectric tangent while suppressing foreign matter that would hinder the wiring pattern or the adhesion between layers. In Comparative Examples 3a and 3b in which aggregates and foreign matter are present on the film, the surface of the film has concavities and convexities conspicuous, and the values of the specific dielectric constant and dielectric tangent are unstable. [Industrial Utilization Possibility]

Since the method of the present invention obtains the thermosetting resin composition of the fluorine-containing resin and its hardened product through a process including a process that does not bring foreign matter or air bubbles into the next step, it has a fine particle size, low viscosity, and excellent stability. When mixed with various resin materials, the fluorine-based resin fine powder does not aggregate, and there is no foreign matter. It can achieve low dielectric constant and low dielectric tangent while suppressing the hindrance of wiring pattern or interlayer adhesion. Therefore, it can be applied to insulating layers of multilayer printed wiring boards, adhesives for circuit boards, laminates for circuit boards, cover films, prepregs, etc.

10: Closed tank with mixer 11: Valve 12: Vacuum pump 13: Vacuum gauge 14: Compressed air supply device 15: Diaphragm pump 16a, 16b, 16c: valve 17, 17a, 17b: liquid delivery pump 18, 18a, 18b: pressure gauge 19: Filtering device 19a, 19b: filter 20: Coating machine 21a, 21b: Valve a~k: Piping

Fig. 1 is a schematic diagram showing an example of the manufacturing steps of the method for manufacturing the thermosetting resin composition of the fluorine-containing resin of the present invention. Fig. 2 is a schematic diagram showing another example of the manufacturing steps of the method for manufacturing the thermosetting resin composition of the fluorine-containing resin of the present invention. Fig. 3 is a schematic diagram showing another example of the manufacturing steps of the method for manufacturing the thermosetting resin composition of the fluorine-containing resin of the present invention.

10: Closed tank with mixer

11: Valve

12: Vacuum pump

13: Vacuum gauge

14: Compressed air supply device

15: Diaphragm pump

16a, 16b: valve

17: Liquid delivery pump

18: Pressure gauge

19: Filtering device

20: Coating machine

21a, 21b: Piping

a~g: Piping

Claims (4)

A method for producing a thermosetting resin composition containing a fluorine-based resin, the thermosetting resin composition containing at least: a non-aqueous dispersion of a fluorine-based resin containing at least a fine powder of a fluorine-based resin and a non-aqueous solvent, and a non-aqueous dispersion containing a thermosetting resin The resin composition of the resin is characterized by: The step of mixing the non-aqueous dispersion of the fluorine-based resin and the resin composition containing the thermosetting resin includes a step including a treatment that does not bring foreign matter or air bubbles into the next step. The method for producing a thermosetting resin composition of a fluorine-containing resin according to claim 1, wherein the fine powder of the fluorine resin is selected from polytetrafluoroethylene, fluorinated ethylene-propylene copolymer, and perfluoroalkoxy polymer , Chlorotrifluoroethylene, tetrafluoroethylene-chlorotrifluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer, polychlorotrifluoroethylene and one or more kinds of fluorine-based resin particles. The method for producing a thermosetting resin composition of a fluorine-containing resin according to claim 1 or 2, wherein the non-aqueous dispersion of the fluorine-based resin contains a fluorine-based additive and/or a fluorine-containing group and a lipophilic group at least The compound represented by the following formula (I),

. The method for producing a thermosetting resin composition of a fluorine-containing resin according to any one of claims 1 to 3, wherein the non-aqueous dispersion of the fluorine resin contains a polymer having a urethane structure.

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