Composition, metal-clad laminate, and method for producing the same

Abstract

To provide a composition enabling the formation of a composition layer having superior dimensional stability, and to provide a metal-clad laminate comprising a composition layer composed of the composition and a method for producing the same.SOLUTION: A composition comprises a fluoropolymer A1 containing units derived from a fluoroolefin and units derived from a monomer having an adhesive functional group, an inorganic filler having a specific surface area of less than 5.5 m2 / g, and a metal oxide, wherein the content of the inorganic filler in solids of the composition is 55 vol.% or more relative to the total volume of the solids of the composition, wherein the inorganic filler is at least one selected from silicon oxide and titanium oxide, wherein the metal oxide is at least one selected from the group consisting of calcium oxide, magnesium oxide, zinc oxide, antimony oxide, and aluminum oxide, and wherein the content of the metal oxide is 0.01 mass% or more and less than 5 mass% relative to the solids mass of the composition.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a composition, a metal clad laminate, and a method for producing the same. [Background technology]

[0002] In recent years, with the increase in the amount of information processed by various electronic devices, mounting technologies such as higher integration of mounted semiconductor devices, higher density wiring, and multi-layering have rapidly advanced. Substrate materials constituting the base material of printed wiring boards used in various electronic devices are required to have low relative dielectric constants and dielectric loss tangents in order to reduce dielectric loss.

[0003] In response to such demands, it has been proposed to use a composition containing a fluororesin, which has excellent dielectric properties (i.e., low dielectric constant and dielectric dissipation factor) among resin materials, for the core portion of a copper-clad laminate (CCL). However, when a fluororesin is used for the core portion of a copper-clad laminate, there is a problem that the adhesion to metal foil and dimensional stability (DS) are low compared to other resins.

[0004] Patent Document 1 discloses that the adhesion between a composition layer made of a composition containing a fluororesin and copper foil is improved by providing an adhesive resin film (a composite film of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) and liquid crystal polymer resin (LCP)) between the composition layer and copper foil.

[0005] Patent Document 2 discloses that a composition layer made of a composition containing a fluororesin is subjected to a plasma treatment to generate COOH groups and OH groups on the surface of the composition layer, and a condensation reaction is caused between the COOH groups and OH groups present on the surface of the composition layer and the surfaces of mating materials such as metal foil or other resin films, thereby improving the adhesion between the composition layer and metal foil.

[0006] In Patent Document 3, a fluorine-containing polymer, which is an adhesive fluorine resin, and a fluorine-containing polymer having a specific surface area of ​​5.5 m 2 / g, and when the content of the inorganic filler is 55 volume% or more with respect to the total volume of the solid content of the composition, the adhesion between a composition layer made of the composition and a metal foil is improved. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2007-98692 A [Patent Document 2] JP 2017-2115 A [Patent Document 3] International Publication No. 2022 / 259981 Summary of the Invention [Problem to be solved by the invention]

[0008] In the inventions disclosed in Patent Documents 1 to 3, although studies were conducted with the aim of improving the adhesion between a composition layer made of a composition containing a fluororesin and a metal foil, no studies were conducted focusing on the dimensional stability of the composition layer.

[0009] In view of the above problems, an object of the present invention is to provide a composition capable of forming a composition layer having excellent dimensional stability, as well as a metal clad laminate including a composition layer made of the composition, and a method for producing the same. [Means for solving the problem]

[0010] Means for Solving the Problems The present inventors have conducted intensive research to solve the above problems, and as a result have found that the above problems can be solved by mixing a specific metal oxide in a specific ratio with a composition containing a fluorinated polymer, which is an adhesive fluororesin, and an inorganic filler, and have thus completed the present invention. Incidentally, when a specific metal oxide is mixed in a specific ratio with a composition containing a fluoropolymer A1, which is an adhesive fluororesin, and an inorganic filler, the dimensional stability of a composition layer made of the composition is improved. This is presumably because the metal oxide captures acidic gases that are generated in small amounts during the film formation and firing of the composition, thereby preventing deterioration of the fluoropolymer A1 and the inorganic filler. That is, the present invention is as follows. [1] A fluorine-containing polymer A1 containing a unit based on a fluoroolefin and a unit based on a monomer having an adhesive functional group, Specific surface area is 5.5m 2 / g or less of an inorganic filler; A composition comprising: The content of the inorganic filler in the solid content of the composition is 55% by volume or more based on the total volume of the solid content of the composition; The inorganic filler is at least one of silicon oxide and titanium oxide, the metal oxide is at least one selected from the group consisting of calcium oxide, magnesium oxide, zinc oxide, antimony oxide, and aluminum oxide; A composition, wherein the content of the metal oxide is 0.01 mass % or more and less than 5 mass % based on the solid mass of the composition. [2] The composition according to the above [1], wherein the adhesive functional group is at least one selected from the group consisting of a carbonyl group, a hydroxyl group, an epoxy group, an amide group, an amino group and an isocyanate group. [3] The composition according to the above [1] or [2], wherein the median diameter (average particle diameter D50) of the metal oxide is 0.1 μm to 50 μm. [4] The composition according to any one of the above [1] to [3], wherein the inorganic filler has a sphericity of 0.80 or more. [5] The composition according to any one of the above [1] to [4], wherein the inorganic filler has a median diameter (average particle diameter D50) of less than 20 μm. [6] The composition according to any one of [1] to [5] above, wherein the content of the inorganic filler in the solid content of the composition is 85 volume % or less based on the total volume of the solid content of the composition. [7] The composition according to any one of the above [1] to [6], wherein the inorganic filler has a surface adsorbed moisture content of 500 ppm by mass or less. [8] A metal clad laminate comprising a composition layer made of the composition according to any one of [1] to [7] above, and a metal layer. [9] The fluorine-containing polymer A1 is contained, and the specific surface area is 5.5 m 2 The metal clad laminate according to [8] above, further comprising an adhesive layer that does not contain an inorganic filler having an average molecular weight of less than 1000 mg / g.

[10] The adhesive layer has a specific surface area of ​​5.5 m 2 / g or more, and a content of the inorganic filler relative to a total volume of the adhesive layer is less than 85 volume %.

[11] The metal clad laminate according to any one of the above [8] to

[10] , wherein the metal layer is a layer made of copper foil.

[12] The metal clad laminate according to any one of the above [8] to

[11] , wherein the ten-point average roughness (Rzjis) of the surface of the metal layer on the side of the composition layer is 2.0 μm or less.

[13] A method for producing a metal clad laminate, comprising applying the composition according to any one of the above [1] to [7] to a surface of a metal layer to obtain a metal clad laminate. Effect of the Invention

[0011] According to the present invention, it is possible to provide a composition capable of forming a composition layer having excellent dimensional stability, as well as a metal clad laminate including a composition layer made of the composition, and a method for producing the same. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of the metal clad laminate of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing another example of the metal clad laminate of the present invention. [Diagram 3]FIG. 3 is a schematic cross-sectional view showing still another example of the metal clad laminate of the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional view showing one example of a resin-coated metal foil used in producing the metal clad laminate of the present invention. [Diagram 5] FIG. 5 is a schematic cross-sectional view showing an example of a wiring board produced using the metal clad laminate of the present invention. [Figure 6] FIG. 6 is a diagram illustrating a dumbbell-shaped test piece used in measuring the breaking elongation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described in detail below. In this specification, the provisions that are considered to be preferable may be adopted arbitrarily, and it can be said that a combination of preferable provisions is more preferable. In this specification, the expression "XX to YY" means "at least XX and at most YY." In this specification, the lower limit and upper limit described in stages for the preferred numerical range (e.g., range of content, etc.) can be combined independently. For example, the description "preferably 10 to 90, more preferably 30 to 60" can be combined with the "preferable lower limit (10)" and the "more preferable upper limit (60)" to form "10 to 60". In addition, in the numerical range described in this specification, the upper limit or lower limit of the numerical range may be replaced with a value shown in the examples. In this specification, the term "unit based on a monomer" refers collectively to an atomic group formed directly by polymerization of one monomer molecule and an atomic group obtained by chemically converting a part of this atomic group. Hereinafter, a unit based on monomer A is also referred to as a monomer A unit. In this specification, "not containing units based on monomers having adhesive functional groups" means that "the content of monomer units having adhesive functional groups is less than 0.05 mol %, preferably 0.03 mol % or less, and more preferably 0.01 mol % or less, relative to the total units contained in the polymer." In this specification, the "solid content of the composition" means, when the composition is a slurry containing a solvent, the components constituting the composition layer other than the solvent. In this specification, the content (vol %) of the fluorinated polymer A1 and the content (vol %) of the inorganic filler relative to the total volume of the "composition layer, adhesive layer or intermediate layer" are determined by measuring the masses of each of the fluorinated polymer A1, the inorganic filler and the metal oxide before mixing (preparing) them, and converting them into volumes from their specific gravities.

[0014] (composition) The composition of the present invention further comprises a fluoropolymer A1 containing units based on a fluoroolefin and units having an adhesive functional group, an inorganic filler, a metal oxide, and, as necessary, a fluoropolymer containing units based on a fluoroolefin and no units based on a monomer having an adhesive functional group, a thermoplastic elastomer, a solvent, and other components. Each component of the composition of the present invention will now be described in detail.

[0015] <Fluoropolymer A1> The fluorine-containing polymer A1 contains units based on a fluoroolefin and units having an adhesive functional group, and may contain units based on monomers other than the fluoroolefin and the monomer having an adhesive functional group, as necessary.

[0016] <<Fluoroolefin-based units>> Examples of the "fluoroolefin" in the "unit based on fluoroolefin" include tetrafluoroethylene (hereinafter referred to as "TFE"), chlorotrifluoroethylene (hereinafter referred to as "CTFE"), trifluoroethylene, vinyl fluoride, vinylidene fluoride (vinylidene fluoride (hereinafter referred to as "VdF")), hexafluoropropylene (hereinafter referred to as HFP), CF 2 =CFOR f1 (where R f1 is a perfluoroalkyl vinyl ether represented by a perfluoroalkyl group having 1 to 10 carbon atoms which may contain an oxygen atom between the carbon atoms, CF2 =CFOR f2 SO 2 X 1 (R f2 is a perfluoroalkylene group having 1 to 10 carbon atoms which may contain an oxygen atom between the carbon atoms; X 1 is a halogen atom or a hydroxyl group), CF 2 =CFOR f2 CO 2 X 2 (where R f2 is the same as above, X 2 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, CF 2 =CF(CF 2 ) p OCF=CF 2 (wherein p is 1 or 2), CH 2 =CX 3 (CF 2 ) q X 4 (where X 3 and X 4 are each independently a hydrogen atom or a fluorine atom, and q is an integer of 2 to 10), perfluoro(2-methylene-4-methyl-1,3-dioxolane), etc. These may be used alone or in combination of two or more. Among these, tetrafluoroethylene and perfluoroalkyl vinyl ether are preferred in terms of their low dielectric tangent. Specific examples of perfluoroalkyl vinyl ethers include CF 2 =CFOCF 3 , C.F. 2 =CFOCF 2 CF 3 , C.F. 2 =CFOCF 2 CF 2 CF 3 , C.F. 2 =CFOCF 2 CF 2 CF 2 CF 3 , C.F. 2 =CFO(CF 2 ) 8 F, etc. These may be used alone or in combination of two or more. Among these, CF 2 =CFOCF2 CF 2 CF 3 is preferred. CH 2 =CX 3 (CF 2 ) q X 4 Specific examples of the 2 =CH(CF 2 ) 2 F, C.H. 2 =CH(CF 2 ) 3 F, C.H. 2 =CH(CF 2 ) 4 F, C.H. 2 =CF(CF 2 ) 3 H, C.H. 2 =CF(CF 2 ) 4 H, etc.

[0017] The content of the units based on fluoroolefin in the fluoropolymer A1 is not particularly limited, but is preferably 90.0 mol% to 99.9 mol%, more preferably 95.0 mol% to 99.8 mol%, particularly preferably 97.0 mol% to 99.7 mol% based on the total molar amount of all units in the fluoropolymer A1. When the content of the units based on fluoroolefin is within the above preferred range, a composition layer having a low relative dielectric constant and dielectric loss tangent can be obtained.

[0018] <<Units based on monomers having adhesive functional groups>> Examples of the "adhesive functional group" in the "monomer having an adhesive functional group" include a carbonyl group, a hydroxyl group, an epoxy group, an amide group, an amino group, an isocyanate group, and the like. These may be used alone or in combination of two or more. Among these, a carbonyl group is preferred from the viewpoint of excellent adhesion of the composition layer to the metal layer.

[0019] Suitable examples of "monomers having adhesive functional groups" include cyclic hydrocarbon monomers having a dicarboxylic acid anhydride group and a polymerizable unsaturated group in the ring (hereinafter simply referred to as "cyclic hydrocarbon monomers"). The above-mentioned "cyclic hydrocarbon monomer" refers to a polymerizable compound that is a cyclic hydrocarbon consisting of one or more 5- or 6-membered rings and has a dicarboxylic anhydride group and an intracyclic polymerizable unsaturated group. The cyclic hydrocarbon is preferably a cyclic hydrocarbon having one or more bridged polycyclic hydrocarbons. That is, it is preferably a cyclic hydrocarbon consisting of a bridged polycyclic hydrocarbon, a cyclic hydrocarbon in which two or more bridged polycyclic hydrocarbons are condensed, or a cyclic hydrocarbon in which a bridged polycyclic hydrocarbon is condensed with another cyclic hydrocarbon.

[0020] The cyclic hydrocarbon monomer also has one or more intracyclic polymerizable unsaturated groups, i.e., polymerizable unsaturated groups present between the carbon atoms constituting the hydrocarbon ring. The cyclic hydrocarbon monomer further has a dicarboxylic anhydride group (-CO-O-CO-), which may be bonded to two carbon atoms constituting the hydrocarbon ring, or to two carbon atoms outside the ring. Preferably, the dicarboxylic anhydride group is bonded to two adjacent carbon atoms constituting the ring of the cyclic hydrocarbon. Furthermore, the carbon atoms constituting the ring of the cyclic hydrocarbon may be bonded to a halogen atom, an alkyl group, a halogenated alkyl group, or other substituent instead of a hydrogen atom.

[0021] Specific examples thereof are those represented by formulae (1) to (8), in which R in formulae (2) and (5) to (8) represents a lower alkyl group having 1 to 6 carbon atoms, a halogen atom selected from a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, or a halogenated alkyl group in which a hydrogen atom in the above lower alkyl group is substituted with a halogen atom.

[0022] [ka] ...Equation (1)

[0023] [ka] ...Equation (2)

[0024] [ka] ...Equation (3)

[0025] [ka] ...Equation (4)

[0026] [ka] ...Equation (5)

[0027] [ka] ...Equation (6)

[0028] [ka] ...Equation (7)

[0029] [ka] ...Equation (8)

[0030] The cyclic hydrocarbon monomer is preferably 5-norbornene-2,3-dicarboxylic anhydride (hereinafter referred to as "NAH") represented by formula (1); cyclic hydrocarbon monomers which are acid anhydrides represented by formulas (3) and (4); and cyclic hydrocarbon monomers in which the substituent R in formulas (2) and (5) to (8) is a methyl group; and more preferably NAH.

[0031] The content of units based on a monomer having an adhesive functional group in the fluoropolymer A1 is not particularly limited, but is preferably 0.01 mol % to 5 mol %, more preferably 0.03 mol % to 3 mol %, and particularly preferably 0.05 mol % to 2 mol %, based on the total molar amount of all units in the fluoropolymer A1. When the content of units based on a monomer having an adhesive functional group is within the above preferred range, a composition layer having excellent adhesion to a metal layer can be obtained.

[0032] <<Other Monomer-Based Units>> Examples of the other monomers include olefins having 2 to 4 carbon atoms, such as ethylene, propylene, and isobutene; vinyl esters, such as vinyl acetate; vinyl ethers, such as ethyl vinyl ether and cyclohexyl vinyl ether; etc. These may be used alone or in combination of two or more.

[0033] The content of units based on other monomers in the fluoropolymer A1 is not particularly limited, but is preferably 0.1 mol % to 10 mol %, more preferably 0.5 mol % to 5 mol %, and particularly preferably 1 mol % to 3 mol %, based on the total molar amount of all units in the fluoropolymer A1.

[0034] When the fluorine-containing polymer A1 contains units based on a fluoroolefin and units based on a monomer having an adhesive functional group, the adhesion of the composition layer to a metal layer can be improved.

[0035] Specific examples of the fluorine-containing polymer A1 include TFE / CF 2 =CFOCF 2 CF 2 CF 3 / NAH copolymer, TFE / HFP / NAH copolymer, TFE / CF 2 =CFOCF 2 CF 2 CF 3 / HFP / NAH copolymer, TFE / VdF / NAH copolymer, TFE / CH 2 =CH(CF 2 )4 F / NAH / ethylene copolymer, TFE / CH 2 =CH(CF 2 ) 2 F / NAH / ethylene copolymer, CTFE / CH 2 =CH(CF 2 ) 4 F / NAH / ethylene copolymer, CTFE / CH 2 =CH(CF 2 ) 2 F / NAH / ethylene copolymer, CTFE / CH 2 =CH(CF 2 ) 2 F / NAH / ethylene copolymer, etc. These may be used alone or in combination of two or more. Among these, TFE / CF 2 =CFOCF 2 CF 2 CF 3 / NAH copolymers are preferred.

[0036] The melting point of the fluorine-containing polymer A1 is not particularly limited and is preferably from 150° C. to 320° C., more preferably from 200° C. to 310° C. The melting point can be adjusted by appropriately selecting the content ratio of units based on fluoroolefin, units based on a monomer having an adhesive functional group, and units based on other monomers.

[0037] The volumetric flow rate (hereinafter referred to as Q value) of the fluoropolymer A is not particularly limited, and is preferably 5 mm 3 / sec~500mm 3 / sec, more preferably 10mm 3 / sec~200mm 3 / sec. The Q value is an index showing the melt fluidity of the fluoropolymer A1 and serves as a guide for the molecular weight. A large Q value indicates a low molecular weight, and a small Q value indicates a high molecular weight.

[0038] The Q value is the extrusion speed of the fluoropolymer A1 when it is extruded under a load of 7 kg into an orifice having a diameter of 2.1 mm and a length of 8 mm at a temperature 50° C. higher than the melting point of the fluoropolymer A1 using a flow tester manufactured by Shimadzu Corp. If this Q value is too small, molding becomes difficult, and conversely, if it is too large, the mechanical strength of the fluoropolymer A1 decreases.

[0039] The method for producing the fluoropolymer A1 is not particularly limited, and the fluoropolymer A1 can be produced by a known method.

[0040] The fluoropolymer A1 obtained by a known production method can be obtained in the form of pellets, powder, or other forms according to a conventional method. Since this fluoropolymer A1 has excellent moldability, it can be molded into a desired shape by injection molding, extrusion molding, press molding, or the like.

[0041] The fluoropolymer A1 can be produced as described above, but a commercially available product can also be used. The commercially available fluoropolymer A1 is not particularly limited, and examples thereof include EA-2000 manufactured by AGC Inc.

[0042] The content of the fluoropolymer A1 in the solid content of the composition of the present invention is not particularly limited as long as it is 45 volume% or less based on the total volume of the solid content of the composition, but from the viewpoints of the linear expansion coefficient and mechanical strength, it is preferably 15 volume% to 45 volume%, more preferably 20 volume% to 40 volume%, and particularly preferably 30 volume% to 40 volume%. When the content of the fluoropolymer A1 in the solid content of the composition of the present invention is within the above preferred range, the adhesion of the composition layer to a metal layer can be improved without impairing the strength of the substrate.

[0043] <Inorganic filler> Examples of inorganic fillers include silicon oxides such as spherical silica; titanium oxide; metal hydroxides such as aluminum hydroxide and magnesium hydroxide; talc; aluminum borate; barium sulfate; and calcium carbonate.

[0044] The inorganic fillers may be hollow inorganic microspheres, such as glass microspheres, ceramic microspheres, and the like. The glass microspheres preferably comprise silica glass or borosilicate glass. Preferably, the ceramic microspheres comprise barium titanate, and more preferably, they comprise barium titanate doped with neodymium or zinc oxide. The hollow inorganic microspheres may be non-porous or porous, and may be crystalline or amorphous. The hollow inorganic microspheres are preferably coated with a silane coupling agent such as phenyltrimethoxysilane, phenyltriethoxysilane, (3,3,3-trifluoropropyl)trimethoxysilane, (tridecafluoro-1,1,2,2-tetrahydrooctyl)-1,1-triethoxysilane, (heptadecafluoro-1,1,2,2-tetrahydrodecyl)-1-triethoxysilane, etc.; a zirconate such as neopentyl(diallyl)oxytri(dioctyl)pyrophosphate zirconate, neopentyl(diallyl)oxytri(N-ethylenediamino)ethyl zirconate, etc.; a titanate such as neopentyl(diallyl)oxytrineodecanoyl titanate, neopentyl(diallyl)oxytri(dodecyl)benzene-sulfonyl titanate, neopentyl(diallyl)oxytri(dioctyl)phosphate titanate, etc., to make them hydrophobic. These may be used alone or in combination of two or more. Among these, silicon oxide and titanium oxide are preferred from the viewpoint of low thermal expansion, and spherical silica is more preferred.

[0045] The specific surface area of ​​the inorganic filler is 5.5 m 2 There is no particular limitation as long as it is less than 4.5 m / g, but it is preferably 2 / g, more preferably less than 3.5m 2 / g, particularly preferably less than 3.0m 2 / g. When the specific surface area of ​​the inorganic filler is within the above preferred range, the adhesion of the composition layer to the metal layer is sufficient. The "specific surface area" here is measured in the same manner as in the examples.

[0046] The sphericity of the inorganic filler is not particularly limited, but is preferably 0.80 or more, more preferably 0.83 or more, and particularly preferably 0.85 or more. When the sphericity of the inorganic filler is within the above preferred range, the quality of through-hole plating can be improved. The "sphericity" here is measured in the same manner as in the examples.

[0047] The median diameter (average particle diameter D50) of the inorganic filler is not particularly limited, but is preferably less than 20 μm, more preferably less than 18 μm, and particularly preferably less than 16 μm. When the median diameter (average particle diameter D50) of the inorganic filler is within the above preferred range, the composition layer has excellent homogeneity and drill processability. The "median diameter (average particle diameter D50)" here is measured in the same manner as in the examples.

[0048] The amount of water adsorbed on the surface of the inorganic filler is not particularly limited, but is preferably 500 ppm by mass or less, more preferably 400 ppm by mass or less, and particularly preferably 300 ppm by mass or less. When the amount of surface adsorbed moisture of the inorganic filler is within the above preferred range, the dielectric tangent of the composition layer can be made low. The "amount of water adsorbed on the surface" here is measured in the same manner as in the examples.

[0049] The content of the inorganic filler in the solid content of the composition is not particularly limited as long as it is 55% by volume or more relative to the total volume of the solid content of the composition, but is preferably 55% by volume to 85% by volume. When the content of the inorganic filler in the solid content of the composition is 55% by volume or more, the linear expansion coefficient of the composition layer is easily suppressed. When the content of the inorganic filler in the solid content of the composition is 85% by volume or less, the dispersibility of the inorganic filler in the composition is good, so that the manufacturability of the composition is excellent. From this viewpoint, the content of the inorganic filler in the solid content of the composition is more preferably 60% by volume to 80% by volume, particularly preferably 65% ​​by volume to 75% by volume.

[0050] <Metal oxide> The metal oxide is not particularly limited as long as it is at least one selected from the group consisting of calcium oxide, magnesium oxide, zinc oxide, antimony oxide, and aluminum oxide, and one or more of them may be used. Among these, magnesium oxide is preferred from the viewpoint of improving dimensional stability and elongation at break.

[0051] The specific surface area of ​​the metal oxide is not particularly limited, but is preferably 0.1 m 2 / g~50m 2 / g, more preferably 0.1m 2 / g~30m 2 / g, particularly preferably 0.3m 2 / g~25m 2 / g. When the specific surface area of ​​the metal oxide is within the above preferred range, water adsorption is reduced, and the dielectric properties are less likely to deteriorate even when the metal oxide is added. The "specific surface area" here is measured in the same manner as in the examples.

[0052] The median diameter (average particle diameter D50) of the metal oxide is not particularly limited, but is preferably 0.10 μm to 50 μm, more preferably 0.10 μm to 10 μm, and particularly preferably 0.10 μm to 5.0 μm. When the median diameter (average particle diameter D50) of the metal oxide is within the above preferred range, the dispersibility during production is good. The "median diameter (average particle diameter D50)" here is measured in the same manner as in the examples.

[0053] The content of the metal oxide in the solid content of the composition is preferably 0.01 mass% or more and less than 5 mass%, more preferably 0.01 mass% or more and less than 3 mass%, and particularly preferably 0.01 mass% to 2.5 mass%, relative to the total mass of the solid content of the composition. When the content of the metal oxide in the solid mass of the composition is within the above preferred range, the composition layer has excellent dimensional stability.

[0054] <Solvent> Examples of the optional solvent include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, butyl acetate, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. These may be used alone or in combination of two or more. Among these, toluene, methyl ethyl ketone, N-methylpyrrolidone, and cyclohexanone are preferred from the viewpoint of the solubility and handling of the composition.

[0055] When the composition of the present invention contains a solvent, the content of the solvent in the composition of the present invention is not particularly limited, but is preferably from 50 to 400 parts by mass, more preferably from 60 to 300 parts by mass, and particularly preferably from 70 to 250 parts by mass, per 100 parts by mass of the total of the fluorinated polymer A1 and the inorganic filler. When the content of the solvent is equal to or more than the above lower limit, the handleability of the composition becomes good, and when the content is equal to or less than the above upper limit, a composition layer having a predetermined thickness can be obtained.

[0056] <Other ingredients> Examples of other optional components include surfactants; defoamers such as silicone defoamers and acrylic acid ester defoamers; heat stabilizers; antistatic agents; UV absorbers; dyes; pigments; lubricants; dispersants such as wetting dispersants; polymers other than those having units based on fluoroolefins such as polyimides; thickeners; and the like. These may be used alone or in combination of two or more. Among these, surfactants are preferred from the viewpoint of mechanical properties.

[0057] <<Surfactants>> The surfactant is used, for example, in preparing the present composition, when a dispersion of a resin powder containing a polymer having units based on fluoroolefin is mixed with an inorganic filler, in order to enhance the dispersibility of the resin powder and the miscibility of the inorganic filler. Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants, and the most suitable compound is appropriately selected. As the surfactant, a nonionic surfactant is preferred from the viewpoint of low dielectric tangent.

[0058] As the nonionic surfactant, a surfactant having a fluorine-containing group and a hydrophilic group (hereinafter, also referred to as "fluorine-based surfactant") is preferable. By using a fluorine-based surfactant, the surface tension of the liquid medium is reduced, the wettability to the surface of the resin powder is improved, and the dispersibility of the resin powder is improved. At the same time, the fluorine-containing group is adsorbed to the surface of the resin powder containing a polymer having a unit based on fluoroolefin, and the hydrophilic group extends into the liquid medium, and the steric hindrance of the hydrophilic group prevents the aggregation of the resin powder, thereby improving the dispersion stability.

[0059] The fluorine-containing group is preferably one having high hydrophobicity, and examples thereof include fluorinated hydrocarbon groups such as perfluoroalkyl groups and perfluoroalkenyl groups (e.g., hexafluoropropylene trimer groups). The perfluoroalkyl groups and perfluoroalkenyl groups may each have a straight-chain structure or a branched structure. The number of carbon atoms in the fluorine-containing group is preferably 2 or more, and more preferably 4 to 20. As the fluorine-containing group, -CF(CF) is preferred because of its bulkiness and excellent adsorption ability. 3 )C(=C(CF 3 ) 2 )(CF(CF 3 ) 2 ) and the like.

[0060] The hydrophilic group is a group that is relatively hydrophilic to the fluorine-containing group, and may be a general hydrophilic group, or may be a group that is usually considered to be a hydrophobic group, as long as it is relatively hydrophilic to the fluorine-containing group. For example, a polyoxypropylene group is relatively hydrophobic to a polyoxyethylene group, which is a hydrophilic group, and is usually considered to be a hydrophobic group, but is relatively less hydrophobic (highly hydrophilic) to the fluorine-containing group, and is therefore a hydrophilic group in the present invention. Examples of the hydrophilic group include a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, a polyoxytetramethylene group, an amino group, a ketone group, a carboxyl group, and a sulfone group. As the hydrophilic group, a polyoxyalkylene group consisting of an oxyalkylene group having 2 to 4 carbon atoms is preferable, and a polyoxyethylene group is particularly preferable.

[0061] The fluorosurfactant may also be a copolymer of a monomer having a fluorine-containing group and a monomer having a hydrophilic group, and as such a surfactant, a copolymer of a monomer having a fluorine-containing group and a monomer having a polyoxyalkylene group is particularly preferred.

[0062] When the fluorosurfactant is a copolymer of a monomer having a fluorine-containing group and a monomer having a hydrophilic group, the weight-average molecular weight of the fluorosurfactant is preferably 1000 to 150000, more preferably 3000 to 100000, and particularly preferably 5000 to 30000. In this case, the fluorine-containing group is more likely to be adsorbed to the surface of the resin powder than to the liquid medium, and the dispersibility and dispersion stability of the resin powder are likely to be improved. In addition, the dispersion in which the resin powder is dispersed can be made to have excellent mixability with different resin materials and their varnishes and excellent coatability. The weight average molecular weight of the fluorosurfactant is measured by gel permeation chromatography (GPC).

[0063] Specific examples of fluorine-based surfactants include perfluoroalkyl group-containing Ftergent M series, Ftergent F209, Ftergent 222F, Ftergent 208G, Ftergent 218GL, Ftergent 710FL, Ftergent 710FM, Ftergent 710FS, Ftergent 730FL, Ftergent 730LM (manufactured by Neos Corporation), Megafac series such as Megafac F-553, Megafac F-555, Megafac F-556, Megafac F-557, Megafac F-559, Megafac F-562, Megafac F-565 (manufactured by DIC Corporation), Unidyne series such as Unidyne DS-403N (manufactured by Daikin Industries, Ltd.), and the like. Among these, FTERGENT 710FL, FTERGENT 710FM and FTERGENT 710FS, which are surfactants in which the fluorine-containing group has a branched structure and three-dimensional bulkiness, are preferred.

[0064] Two or more surfactants may be used in combination. In this case, at least a part of the two or more surfactants is preferably a fluorine-based surfactant. A part of the two or more surfactants may be a surfactant that does not have a fluorine-containing group.

[0065] When the composition of the present invention contains a surfactant, the content of the surfactant is not particularly limited and is preferably 3 to 30 parts by mass, more preferably 5 to 20 parts by mass, per 100 parts by mass of the fluoropolymer A1.

[0066] The composition of the present invention is cured, for example, by heating the composition at 330° C. to 380° C. for 5 to 60 minutes, to form a composition layer which will be described later.

[0067] (Metal-clad laminate) The metal clad laminate of the present invention comprises a composition layer made of the composition of the present invention and a metal layer, and optionally further comprises an adhesive layer and an intermediate layer.

[0068] FIG. 1 is a schematic cross-sectional view showing an example of the metal clad laminate of the present invention. As shown in FIG. 1, a metal clad laminate 11 has a composition layer (insulating layer) 12 made of the composition of the present invention, and metal layers 13 disposed on both sides of the composition layer (insulating layer) 12. The metal clad laminate of the present invention may be a double-sided metal foil-clad laminate in which metal layers 13 are arranged on both sides of a composition layer 12 as shown in Fig. 1, or may be a single-sided metal foil-clad laminate in which a metal layer 13 is arranged on one side of a composition layer 12 (see Fig. 4 described later). Furthermore, the metal clad laminate of the present invention may have a structure in which a large number of laminate structures each composed of a metal layer 13 and a composition layer 12 are laminated. A single-sided metal foil-clad laminate using copper foil as the metal layer 13 is called a resin coated copper foil (RCC), and a double-sided metal foil-clad laminate using copper foil as the metal layer 13 is called a copper clad laminate (CCL).

[0069] In the metal clad laminate of the present invention, the linear expansion coefficient CTE of the composition layer is preferably 10 ppm / ° C. to 50 ppm / ° C., more preferably 15 ppm / ° C. to 35 ppm / ° C. When the linear expansion coefficient CTE is within the above-mentioned preferred range, the difference in linear expansion coefficient from the copper foil becomes small, and the process compatibility during substrate processing becomes good. The "coefficient of linear expansion CTE" here is measured in the same manner as in the examples.

[0070] According to the above-mentioned configuration, a metal clad laminate is obtained that can be used to fabricate a substrate with sufficiently reduced dielectric loss.

[0071] FIG. 2 is a schematic cross-sectional view showing another example of the metal clad laminate of the present invention. 2, metal clad laminate 21 has composition layer 12 made of the composition of the present invention, metal layers 13 disposed on both outer surfaces of composition layer 12, and adhesive layer (primer layer) 14 disposed between composition layer 12 and metal layer 13. That is, metal clad laminate 21 has metal layer 13, adhesive layer 14, and composition layer 12 in this order, adhesive layer 14 is provided on the surface of metal layer 13, and composition layer 12 is provided on the surface of adhesive layer 14.

[0072] FIG. 3 is a schematic cross-sectional view showing still another example of the metal clad laminate of the present invention. As shown in FIG. 3, the metal clad laminate 31 is similar to the metal clad laminate 21 of FIG. 2, except that it further includes an intermediate layer 15 that divides the composition layer 12 into two.

[0073] <Composition layer> The composition layer is a layer made of the composition of the present invention. The thickness of the composition layer is not particularly limited, but is preferably 50 μm to 300 μm, more preferably 70 μm to 200 μm, and particularly preferably 100 μm to 150 μm. When the thickness of the composition layer is equal to or greater than the lower limit, disconnection of the circuit wiring due to deformation or bending can be easily prevented. When the thickness of the composition layer is equal to or less than the upper limit, the wiring board to be produced is excellent in flexibility, size, and weight reduction.

[0074] The dielectric loss tangent Df of the composition layer at a frequency of 10 GHz is preferably 0.0020 or less, more preferably 0.0015 or less, and particularly preferably 0.0010 or less, from the viewpoint of suppressing transmission loss. The "dielectric tangent Df" here is measured in the same manner as in the examples.

[0075] The dielectric constant Dk of the composition layer at a frequency of 10 GHz is preferably 2.0 to 4.0, more preferably 2.2 to 3.5, and particularly preferably 2.4 to 3.2. When the dielectric constant Dk of the composition layer is equal to or greater than the lower limit, the ease of production and the range of options are increased. When the dielectric constant Dk of the composition layer is equal to or less than the upper limit, the transmission loss is suppressed. The "dielectric constant Dk" here is measured in the same manner as in the examples.

[0076] The dimensional stability DS of the composition layer is determined by the content of the inorganic filler. For example, when the inorganic filler is added at 71 volume %, it is preferably 0 ppm to 500 ppm, more preferably 100 ppm to 500 ppm, and particularly preferably 300 ppm to 500 ppm. When the inorganic filler is added at 66.5 volume %, it is preferably 500 to 1300 ppm, more preferably 600 to 1200 ppm, and particularly preferably 800 to 1100 ppm. When the inorganic filler is added at 69.5 volume %, it is preferably 400 to 800 ppm, more preferably 500 to 775 ppm, and particularly preferably 600 to 750 ppm. When the inorganic filler is added at 68.0 volume %, it is preferably 500 to 1200 ppm, more preferably 600 to 1150 ppm, and particularly preferably 700 to 1100 ppm. When the dimensional stability DS of the composition layer is in the above preferred range, thermal stability during processing into a substrate can be ensured, and warping of the substrate during the processing process can be avoided. The above values ​​are the amount of change before and after the dimensional stability confirmation test, i.e., absolute values, and the value "2.0" includes elongation and contraction of 2.0 ppm. The "dimensional stability DS" here is measured in the same manner as in the examples.

[0077] The breaking elongation of the composition layer is preferably 2% to 10%, more preferably 3% to 8%. When the breaking elongation of the composition layer is in the above-mentioned preferred range, the flexibility of the substrate can be ensured, and the occurrence of breakage or cracks during processing can be prevented. The "breaking elongation" here is measured in the same manner as in the examples.

[0078] <Metal layer> As the metal layer, for example, a conductive metal foil having low electrical resistance, such as copper foil, silver foil, gold foil, or aluminum foil, can be used, with copper foil being preferred. The metal layer may be made of one metal alone, or may be made of a combination of multiple metals. A method of using multiple metals in combination is to plate a metal foil, and for example, a gold-plated copper foil can be used as the metal foil. Depending on the thickness of the metal layer, a metal foil with a carrier having a release layer and a carrier may be used to improve handling. Furthermore, the metal layer may be a metal foil (raw foil) that is electrolytically or rolled, or may have one or both sides subjected to a surface treatment. Examples of the surface treatment include rust prevention treatment, silane treatment, surface roughening treatment, and barrier formation treatment.

[0079] Examples of commercially available metal foils that can be used as the metal layer include TQ-M4-VSP (product name, manufactured by Mitsui Mining & Smelting Co., Ltd., copper foil, Rzjis: 0.6 μm, thickness: 18 μm) and SI-VSP-AM2R, AM3R (product name, manufactured by Mitsui Mining & Smelting Co., Ltd., copper foil, Rzjis: 0.6 μm, thickness: 18 μm).

[0080] The thickness of the metal layer is not particularly limited, but is preferably 0.1 μm to 100 μm, more preferably 0.2 μm to 50 μm, and particularly preferably 1.0 μm to 30 μm. If the thickness of the metal layer is within the above preferred range, a typical method for forming a wiring pattern on a wiring board, such as a modified semi-additive (MSAP) method or a subtractive method, can be easily adopted.

[0081] The ten-point average roughness (Rzjis) of the surface of the metal layer on the side of the composition layer is not particularly limited, but is preferably 2.0 μm or less, more preferably 1.0 μm or less, and particularly preferably 0.8 μm or less. These upper limits are preferable from the viewpoint of reducing the conductor loss caused by the metal layer, which may increase due to the skin effect of the metal foil when used in the high frequency range, and reducing the transmission loss. The skin effect means a phenomenon in which high-frequency electric signals flow only near the surface of the metal layer. Due to the skin effect, electric signals flow following the unevenness of the metal layer surface, so the rougher the metal layer, the longer the transmission distance of the electric signal, and the worse the conductor loss may be. The ten-point average roughness (Rzjis) of the surface of the metal foil on the side of the composition layer is not particularly limited, but is preferably 0.10 μm or more, more preferably 0.15 μm or more, and particularly preferably 0.20 μm or more. These lower limit values ​​are preferable from the viewpoint of improving the adhesion between the metal layer and the composition layer or the adhesive layer described later. The "ten-point average roughness (Rzjis)" here is measured in the same manner as in the examples.

[0082] The peel strength (degree of adhesion) at the interface between the metal layer and the composition layer or the adhesive layer is preferably 4 N / cm to 30 N / cm, 5 N / cm to 25 N / cm, and particularly preferably 6 N / cm to 20 N / cm. When the peel strength (degree of adhesion) is equal to or greater than the lower limit, the substrate has excellent processability. When the peel strength (degree of adhesion) is equal to or less than the upper limit, the substrate has excellent mass productivity. The "peel strength (degree of adhesion)" here is measured in the same manner as in the examples.

[0083] <Adhesive layer> The adhesive layer contains the above-mentioned fluorine-containing polymer A1, and optionally contains an inorganic filler and other components. 2 It is preferable that the inorganic filler does not contain an inorganic filler having a molecular weight of less than 1 / g. The adhesive layer is preferably a layer that functions as a primer layer for improving the adhesion between the metal layer and the composition layer. The fluoropolymer A1 contained in the adhesive layer is the same as the fluoropolymer A1 contained in the composition constituting the composition layer. Other components that can be contained in the adhesive layer are the same as other components that can be contained in the composition constituting the composition layer.

[0084] The specific surface area of ​​the inorganic filler that can be contained in the adhesive layer is preferably 5.5 m 2 / g or more, more preferably 5.5m 2 / g~30m 2 / g, and even more preferably 5.5m 2 / g~25m 2 / g, particularly preferably 5.5m 2 / g~20m 2 / g. When the specific surface area of ​​the inorganic filler in the adhesive layer is within the above preferred range, the adhesive layer can be made thin and the amount of inorganic filler added can be increased. The "specific surface area" here is measured in the same manner as in the examples.

[0085] The median diameter (average particle diameter D50) of the inorganic filler that can be contained in the adhesive layer is not particularly limited, and in one embodiment, it is preferably less than 1 μm, and in another embodiment, it is preferably 0.1 μm to 5 μm, and more preferably 0.1 μm to 2 μm. When the median diameter (average particle diameter D50) of the inorganic filler in the adhesive layer is within the above preferred range, a thin and homogeneous adhesive layer can be obtained. The "median diameter (average particle diameter D50)" here is measured in the same manner as in the examples.

[0086] The inorganic filler that can be contained in the adhesive layer differs from the inorganic filler contained in the composition that constitutes the composition layer only in terms of specific surface area and median diameter (average particle diameter D50), and is otherwise similar.

[0087] The content of the inorganic filler in the adhesive layer is not particularly limited, but is preferably less than 85 volume %, more preferably 40 volume % or more and less than 85 volume %, even more preferably 50 volume % to 75 volume %, and particularly preferably 55 volume % to 70 volume %, relative to the total volume of the adhesive layer. When the content of the inorganic filler in the adhesive layer is within the above preferred range, the relative dielectric constant Dk of the adhesive layer can be made close to the Dk of the composition layer.

[0088] The thickness of the adhesive layer is not particularly limited, but is preferably 0.1 μm to 12 μm, more preferably 0.3 μm to 7 μm, and particularly preferably 1 μm to 4 μm. When the thickness of the adhesive layer is equal to or greater than the lower limit, the adhesion to the metal foil and the composition layer is easily improved. When the thickness of the adhesive layer is equal to or less than the upper limit, the adhesive layer is excellent in reducing transmission loss in the high frequency range and suppressing warping and peeling.

[0089] The dielectric loss tangent Df of the adhesive layer at a frequency of 10 GHz is preferably 0.003 or less, more preferably 0.0025 or less, and particularly preferably 0.002 or less, from the viewpoint of suppressing transmission loss. The "dielectric tangent Df" here is measured in the same manner as in the examples.

[0090] The relative dielectric constant Dk of the adhesive layer at a frequency of 10 GHz is preferably 2.0 to 4.0, more preferably 2.2 to 3.5, and particularly preferably 2.4 to 3.2. When the relative dielectric constant Dk of the adhesive layer is equal to or greater than the lower limit, the ease of production and the range of options are increased. When the relative dielectric constant Dk of the adhesive layer is equal to or less than the upper limit, the transmission loss is suppressed. The "dielectric constant Dk" here is measured in the same manner as in the examples.

[0091] <Middle Class> Furthermore, an intermediate layer containing a fluoropolymer containing units based on a fluoroolefin and not containing units based on a monomer having an adhesive functional group, not containing the above-mentioned fluoropolymer A1, and containing other components as necessary, may be provided. When an intermediate layer is provided, it is preferably disposed between the composition layers, that is, it is preferably a layer that functions as a layer that divides the composition layers to improve adhesion.

[0092] (Metal Clad Laminate Manufacturing Method) The method for producing the metal clad laminate of the present invention is not particularly limited, and a conventionally known method can be appropriately used, for example, a method in which the composition of the present invention is applied to the surface of a metal layer, and then heated and pressed to cure the composition to obtain a metal clad laminate can be used. In addition, a lamination molding method can also be used. Here, the coating device used for coating can be appropriately selected depending on the film thickness of the metal foil to be formed, and examples thereof include a bar coater, a comma coater, a die coater, a roll coater, a gravure coater, etc. These may be used alone or in combination of two or more.

[0093] Methods for producing the metal-clad laminate of the present invention using a resin-coated metal foil described below include, for example, a method in which two sheets of resin-coated metal foil are stacked with the resin sides facing each other, and then heated and pressurized to laminate together to produce a laminate with metal foil on both sides; and a method in which a metal foil is stacked on the resin side of a resin-coated metal foil, and then heated and pressurized to laminate together to produce a laminate with metal foil on both sides. Heating and pressing conditions can be appropriately set depending on the thickness of the laminate to be produced, the type of composition, etc., and can be, for example, a temperature of 300° C. to 400° C., a pressure of 5 MPa to 10 MPa, and a time of 30 to 100 minutes.

[0094] The viscosity at 23°C of the composition used in the method for producing a metal clad laminate of the present invention is not particularly limited, and is preferably 10 mPa·s to 200 mPa·s, more preferably 20 mPa·s to 160 mPa·s, and particularly preferably 30 mPa·s to 120 mPa·s. When the viscosity of the composition at a temperature of 23° C. is within the above preferred range, the adhesive strength between the metal layer and the composition layer can be strengthened.

[0095] <Metal foil with resin> FIG. 4 is a schematic cross-sectional view showing one example of a resin-coated metal foil used in producing the metal clad laminate of the present invention. As shown in FIG. 4, a resin-coated metal foil 41 has a configuration in which a composition layer 12 made of the composition of the present invention and a metal layer 13 are laminated. The resin-coated metal foil 41 may comprise a composition layer 12 made of a pre-cured composition and a metal layer 13, or may comprise a composition layer 12 made of a semi-cured product of the composition and a metal layer 13. According to the above-mentioned configuration, it is possible to obtain a resin-coated metal foil from which a metal clad laminate having sufficiently reduced dielectric loss can be produced.

[0096] The resin-coated metal foil 41 can be produced, for example, by applying a composition to the surface of the metal foil 13 such as a copper foil and then drying it. Here, the coating device used for coating can be appropriately selected depending on the film thickness of the metal foil to be formed, and examples thereof include a bar coater, a comma coater, a die coater, a roll coater, a gravure coater, etc. These may be used alone or in combination of two or more.

[0097] In the resin-coated metal foil of the present invention, the composition or the semi-cured product of the composition may be a composition which has been dried or heated and dried.

[0098] The conditions for drying or heat drying in the manufacturing method of the resin-coated metal foil 41 are not particularly limited, and it is preferable that the heating temperature is 300° C. to 400° C. and the heating time is about 5 to 60 minutes. By such drying or heat drying, the solvent is volatilized, and the solvent is reduced or removed, thereby obtaining the resin-coated metal foil 41 in an uncured or semi-cured state.

[0099] A wiring circuit is arranged on the surface of the metal clad laminate of the present invention to manufacture a wiring board. As a method for forming a wiring circuit on the surface of the metal clad laminate of the present invention to manufacture a wiring board, a conventionally known method can be appropriately used, for example, a subtractive method for etching a metal layer on the surface of the metal clad laminate of the present invention, an MSAP method for plating the surface, etc. can be used. FIG. 5 is a schematic cross-sectional view showing an example of a wiring board manufactured using the metal clad laminate of the present invention, in which a metal layer 13 arranged on one side of a composition layer 12 via an adhesive layer 14 is etched (partially removed) to form a wiring circuit 16. EXAMPLES

[0100] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples.

[0101] The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following description. Examples 1 to 10 are working examples, and Examples 11 to 16 are comparative examples.

[0102] <Details of ingredients used> Fluoropolymer A1: EA-2000 (AGC Corporation product, fluoroolefin (tetrafluoroethylene and CF 2 =CFOCF 2 CF 2 CF 3 Fluorine-containing polymer containing units based on 5-norbornene-2,3-dicarboxylic anhydride (NAH), adhesive functional group: carbonyl group) and a monomer having an adhesive functional group, melting point of 300°C measured by DSC) Inorganic filler B1: FB-8C (Denka Co., Ltd. product, spherical silica particles, median diameter (average particle diameter D50): 8.3 μm, specific surface area 1.6 m 2 / g, sphericity 0.85 or more, surface adsorption moisture content 198 mass ppm) Metal oxide C1: Magnesium oxide (reagent manufactured by Kanto Chemical Co., Ltd. or PyroXuma 5301 manufactured by Kyowa Chemical Industry Co., Ltd., median diameter (average particle diameter D50): 2.9 μm, BET specific surface area: 1.4 to 3.5 m 2 / g) Metal oxide C2: Aluminum oxide (manufactured by Junsei Chemical Co., Ltd., median diameter (average particle diameter D50): 40 μm to 50 μm, BET specific surface area: 21.4 m 2 / g) Metal oxide C3: Antimony oxide (Kanto Chemical Co., Ltd., median diameter (average particle diameter D50): 1.0 μm to 10 μm, BET specific surface area: 0.3 m 2 / g) Metal oxide C4: Zinc oxide (Kanto Chemical Co., Ltd., median diameter (average particle diameter D50): approx. 0.6 μm, BET specific surface area: 2.7 m 2 / g) Metal oxide C5: Titanium oxide (FERRO 203-4, median diameter (average particle diameter D50): 1.2 μm, BET specific surface area: 4.2 m 2 / g) Surfactant: Nonionic fluorosurfactant (Neos, Futergent 710FL)

[0103] (Examples 1 to 16) A total of 480 g of the polymer and inorganic filler shown in the component column of the composition in Table 1, 376 g of N-methylpyrrolidone, 8 g of Futergent 710FL as a solid mass (16 g in 50% ethyl acetate solution), and metal oxide were weighed out so as to be the mass% shown in Table 1 relative to the polymer and inorganic filler amounts, and the mixture was stirred and mixed for 20 to 90 minutes while applying high shear using Magic Lab manufactured by IKA Co., Ltd., to obtain a slurry-like composition.

[0104] The slurry was applied to a surface of a 18 μm-thick copper foil (TQ-M4-VSP, Rzjis: 0.6 μm, manufactured by Mitsui Mining & Smelting Co., Ltd.) to a thickness of 125 μm by a doctor blade method, dried in an atmospheric environment at room temperature for 12 hours, and then heated and dried at 350° C. for 20 minutes in a nitrogen atmosphere to form a composition layer. This resulted in a single-sided metal-clad laminate having a composition layer and a metal layer made of copper foil. Two of the single-sided metal clad laminates were stacked with the resin sides facing each other and pressed in a vacuum hot press apparatus at a temperature of 330° C. and a pressure of 8 MPa for 60 minutes to obtain a double-sided metal clad laminate. In the obtained double-sided metal-clad laminate, the ratio of the total volume of the polymer and inorganic filler to the total volume of the composition layer was 100 volume %, and the thickness of the composition layer was 125 μm. The double-sided metal clad laminates of the respective examples were evaluated as described below. The results are shown in Table 1.

[0105] <Median diameter of inorganic fillers and metal oxides (average particle diameter D50)> The inorganic filler was dispersed in water and the volumetric particle size distribution was measured using a laser diffraction / scattering particle size distribution analyzer (MICROTRAC HRA DHSX100, manufactured by Nikkiso Co., Ltd.), and the median diameter (average particle diameter D50) was calculated. However, when the median diameter (average particle diameter D50) of the above components was known at the time of procurement, the known median diameter (average particle diameter D50) was used.

[0106] <Specific surface area of ​​inorganic filler and metal oxide> A gas adsorption measurement device (MICROTRAC MRB, BELSORP MAX) was used to measure N adsorption on inorganic fillers and metal oxides. 2 The gas was adsorbed, and the specific surface area was calculated from the adsorption behavior.

[0107] <Sphericity of inorganic filler> The sphericity of the inorganic filler was measured using FPIA-3000 manufactured by Sysmex Corporation based on the following calculation formula. A: Area of ​​particle image PM: Perimeter of particle image B: Area of ​​a perfect circle with a perimeter of PM HD: Equivalent circle diameter In this case, the equivalent circle diameter (HD) = (4 / π×A) 1 / 2 and Sphericity=A / B

[0108] <Amount of moisture adsorbed on the surface of inorganic filler> The amount of moisture adsorbed on the surface of the inorganic filler was measured by coulometric titration using a trace moisture analyzer CA-200 manufactured by Mitsubishi Chemical Analytech Co., Ltd.

[0109] <Peel strength> A rectangular test piece measuring 100 mm in length and 10 mm in width was cut out from a metal clad laminate described later. The copper foil was peeled off from the composition layer to a position 10 mm from one end in the longitudinal direction of the test piece. One end of the peeled copper foil was peeled off at 90° at a pulling speed of 50 mm / min using a tensile tester (Shimadzu Autograph AGS-X), and the load value at which the load was constant against the displacement was defined as the peel strength (N / cm).

[0110] <Ten-point average roughness Rzjis> The roughened surface of the copper foil was measured using a Surfcorder SE600 manufactured by Kosaka Laboratory in accordance with the method specified in Appendix JA of JIS B 0601:2013.

[0111] <Dielectric constant Dk and dielectric tangent Df> The metal foils on both sides of the double-sided metal laminate were etched away using an aqueous iron chloride solution to obtain a composition layer (thickness: 125 μm). The relative dielectric constant Dk and dielectric loss tangent Df were measured using a cavity resonator and a vector network analyzer at 25° C. and 10 GHz according to the method specified in JIS R 1641:2007. It is preferable that both the relative dielectric constant Dk and the dielectric loss tangent Df are small.

[0112] <Dimensional stability DS> Measurement of dimensional stability (DS) was performed with reference to the test method of IPC-TM-650 2.4.39 Dimensional Stability, Glass Reinforced Thin Laminates. For the purpose of simplifying screening, the dimensions were measured by measuring the lengths of the four sides of measurement samples cut into 70 mm squares from the double-sided metal laminates produced in Examples 1 to 16. Precision measurement of sample dimensions was performed using a NIKON NEXIV-VMZS4540. The evaluation procedure is shown below. 1. The dimensions of all four sides of a cut-out 70 mm square double-sided metal laminate sample were measured (reference values). 2. The metal foil on both sides of the sample was etched away using an aqueous solution of iron chloride, and the resulting composition layer was air-dried and then the dimensions of all four sides were measured. 3. The composition layer of step 2 above was heated in an oven at 105° C. for 4 hours, removed from the oven and cooled at room temperature for 1 hour, after which the dimensions of the four sides were measured (reference values). 4. The composition layer was then heated in an oven at 150° C. for 2 hours, and cooled for 1 hour in the same manner as in 3 above, after which the dimensions of the four sides were measured. 5. The point in time of 2 above is defined as the initial dimension, and the difference between the dimensions of the four sides after 4 above is calculated for each side, and the average value is divided by the initial dimension (unit is converted to ppm; the calculated value is multiplied by 10 6 The value obtained by multiplying the displacement by 100% was defined as the DS displacement and is shown in Table 1.

[0113] <Breaking elongation> From the composition layer, a dumbbell-shaped test piece (see FIG. 6) was cut out with reference to the dumbbell-shaped No. 1 shape specified in JIS K 6251:2017. The units of the numbers in FIG. 6 are millimeters (mm). Both ends of the test piece were clamped with a chuck distance of 50 mm, and the movement amount at the time of tensile break was measured at a tensile speed of 1 mm / min using a tensile tester (Shimadzu Corporation Autograph AGS-X), and the breaking elongation (%) was calculated as the increase in the chuck distance / initial chuck distance.

[0114] <Coefficient of linear expansion CTE> A test piece of 4 mm x 30 mm was cut out from the composition layer. The linear expansion coefficient CTE (xy) in the length direction of this test piece was measured using a thermomechanical analyzer (HITACHI, TMA7100). Specifically, the sample was first heated once from 20 ° C to 280 ° C at a rate of 10 ° C / min, held at 280 ° C for 3 minutes, and then cooled to -20 ° C at a rate of 10 ° C / min. After the temperature stabilized at -20 ° C, the sample was heated at a rate of 5 ° C / min in the temperature range of -20 ° C to 280 ° C, and the displacement of the length of the sample was measured. After the measurement was completed, the linear expansion coefficient CTE (ppm / ° C) from 30 ° C to 200 ° C was obtained from the displacement of the sample from 30 ° C to 200 ° C.

[0115] [Table 1]

[0116] The dimensional stability of Examples 1 to 3 was superior to that of Example 11, which did not contain any metal oxide. The dimensional stability of Example 4 was superior to that of Example 12, which did not contain any metal oxide. The dimensional stability of Example 5 was superior to that of Example 13, which did not contain any metal oxide. The dimensional stability of Examples 6-7 was superior to that of Example 14, which did not contain any metal oxide. The dimensional stability of Examples 8 to 10 was superior to that of Example 15, which contained titanium oxide. The dimensional stability of Examples 8 to 10 was superior to that of Example 16 in which the metal oxide content was 5% by mass or more based on the solid content mass of the composition. [Industrial Applicability]

[0117] The present invention has wide industrial applicability in technical fields related to electronic materials and various devices using the same. [Explanation of symbols]

[0118] 11,21,31: Metal clad laminate 12: Composition layer (insulating layer) 13: Metal layer 14: Adhesive layer (primer layer) 15: Middle class 16:Wiring circuit 41: Metal foil with resin

Claims

1. a fluorine-containing polymer A1 containing a unit based on a fluoroolefin and a unit based on a monomer having an adhesive functional group; Specific surface area is 5.5m ２ / g or less of an inorganic filler; A composition comprising: The content of the inorganic filler in the solid content of the composition is 55% by volume or more based on the total volume of the solid content of the composition; The inorganic filler is at least one of silicon oxide and titanium oxide, the metal oxide is at least one selected from the group consisting of calcium oxide, magnesium oxide, zinc oxide, antimony oxide, and aluminum oxide; A composition, wherein the content of the metal oxide is 0.01 mass % or more and less than 5 mass % based on the solid content mass of the composition.

2. 2. The composition according to claim 1, wherein the adhesive functional group is at least one selected from the group consisting of a carbonyl group, a hydroxyl group, an epoxy group, an amide group, an amino group, and an isocyanate group.

3. The composition according to claim 1 or 2, wherein the median diameter (average particle diameter D50) of the metal oxide is 0.1 μm to 50 μm.

4. The composition according to claim 1 or 2, wherein the inorganic filler has a sphericity of 0.80 or more.

5. The composition according to claim 1 or 2, wherein the inorganic filler has a median diameter (average particle diameter D50) of less than 20 μm.

6. The composition according to claim 1 or 2, wherein a content of the inorganic filler in the solid content of the composition is 85 volume % or less based on a total volume of the solid content of the composition.

7. The composition according to claim 1 or 2, wherein the inorganic filler has a surface adsorbed moisture amount of 500 ppm by mass or less.

8. A metal clad laminate comprising a composition layer comprising the composition according to claim 1 or 2, and a metal layer.

9. The fluoropolymer A1 is contained, and the specific surface area is 5.5 m ２ The metal clad laminate of claim 8 , further comprising an adhesive layer that does not contain an inorganic filler having an average molecular weight of less than 1.0 μm / g.

10. The adhesive layer has a specific surface area of ​​5.5 m ２ 10. The metal clad laminate according to claim 9, further comprising an inorganic filler having a viscosity of 1000 psig / g or more, and a content of the inorganic filler relative to a total volume of the adhesive layer is less than 85 vol%.

11. The metal clad laminate according to claim 8 or 9, wherein the metal layer is a layer made of copper foil.

12. The metal clad laminate according to claim 8 or 9, wherein the ten-point average roughness (Rzjis) of the surface of the metal layer on the side of the composition layer is 2.0 μm or less.

13. A method for producing a metal clad laminate, comprising applying the composition according to claim 1 or 2 to a surface of a metal layer to obtain a metal clad laminate.

Images