WO2009107845A1

WO2009107845A1 - Metal/cured resin laminate

Info

Publication number: WO2009107845A1
Application number: PCT/JP2009/053906
Authority: WO
Inventors: 孝司木内; 明彦吉原
Original assignee: 日本ゼオン株式会社
Priority date: 2008-02-28
Filing date: 2009-03-02
Publication date: 2009-09-03

Abstract

Disclosed is a metal/cured resin laminate having a metal layer and a cured conjugated diene polymer layer, wherein the surface of the metal layer that attaches to the cured conjugate diene polymer layer has a roughness (Rz) not exceeding 2,500nm, and the strength of adhesion between the metal layer and the cured conjugated diene polymer layer not less than 0.5kN/m.

Description

Metal-cured resin laminate

The present invention relates to a metal-cured resin laminate suitable for a multilayer wiring board including an electronic circuit wiring board and a method for producing the same.

A circuit board is generally composed of a dielectric layer and a conductor layer. In recent years, with the advent of advanced information technology, information transmission has begun to increase in speed and frequency, and microwave communication and millimeter wave communication have become a reality. These circuit boards in the high frequency era need to reduce noise and transmission loss at high frequencies to the utmost. Selection of a dielectric material having a high Q value represented by (1 / dielectric loss tangent) and the dielectric layer Formation of a conductor layer with a smooth adhesion interface has become an important issue.

As a dielectric material, an epoxy resin having a Q value of usually about 10 to 30 is used in a circuit board used in a conventional low frequency (k to MHz range). However, in a high-frequency circuit board used in the GHz region, if the Q value is small, the performance and reliability of the circuit board are not sufficient, and several times to 10 times or more, more specifically, the Q value is 100 or more than the conventional one. Preferably, 300 or more, more preferably 500 or more materials have been demanded.

Conventionally, the surface of the conductor layer has been roughened so as to form physical adhesion (anchor effect) with the dielectric material because the adhesion between the conductor layer (metal) and the dielectric layer (organic material) is poor. It was used. For example, as a commercially available copper foil, an electrolytic copper foil in which a large number of granular protrusions of about 7 to 8 μm are formed on one surface of a 9 to 18 μm thick copper foil is used. However, since information transmission in the high frequency region is performed only on the surface of the conductor layer, not the entire conductor layer, if the surface of the conductor layer is rough, transmission delay and noise are caused. On the other hand, when a conductor layer whose surface is not roughened is used, there arises a problem that the adhesion between the conductor layer and the dielectric layer becomes worse. In particular, the dielectric material having a high Q value has reduced the polar groups in the epoxy resin or the like to the maximum in order to increase the Q value, so that a big problem that the adhesion with the smooth conductor layer becomes more difficult occurs. It was.

Patent Document 1 discloses a thermoplastic block copolymer such as 1,2-polybutadiene having a molecular weight of less than 5,000 at room temperature and a styrene-butadiene-styrene triblock polymer which is a solid polymer as a dielectric material having a high Q value. Mixing a crosslinking agent such as dicumyl peroxide and t-butylperoxyhexine-3, a crosslinking aid such as divinylbenzene and polyfunctional acrylate, and a filler surface-treated with a large amount of silane coupling agent. It is disclosed that a fiber reinforced material is impregnated as a slurry and then the solvent is removed to prepare a prepreg, and then a plurality of prepregs are laminated between two copper foils and cured to produce a laminate. The dielectric loss of the metal-cured resin laminate disclosed herein has a Q value measured at 1 to 10 GHz of 169.5 to 285.7, and an adhesive strength with a normal copper foil of 2.1. It is shown to be in the range of ~ 5.0 pli (0.37 to 0.88 kN / m). However, in the method for producing a metal-cured resin laminate disclosed herein, there is a problem that adhesion cannot be obtained when a smooth copper foil is used.

On the other hand, Patent Document 2 discloses a technique in which an adhesion promoting elastomer layer such as ethylene-propylene-diene elastomer is disposed between a cured resin layer such as polybutadiene or polyisoprene resin and a metal layer to bond the cured resin and the metal. Is disclosed. Surface roughness of copper foils such as 0.5-1 ounce Yats Foil TAX foil, TWX foil, Cotech TAX foil, Circuit Foil NT-TOR foil, NT-TWS foil, Mitsui 3EC foil ( Rz) is usually in the range of 5 to 10 μm, and the adhesion strength between the copper foil and the cured resin is 3 to 4 pli (0.53) unless an adhesion promoting elastomer layer such as ethylene-propylene-diene elastomer is interposed. However, it is disclosed that it can be improved to about 5 to 7 pli (0.88 to 1.23 kN / m) by interposing an adhesion promoting elastomer layer. However, when an adhesion promoting elastomer layer is provided, the dielectric constant at 10 GHz decreases from 3.457 to 3.449. However, this method is sufficient when the Q value is reduced from 271 to 222 and the roughness of the copper foil is reduced. There is a problem that can not be adhered.

JP-A-8-208856 JP 2005-502192 A

An object of the present invention is to provide a metal-cured resin laminate exhibiting excellent transmission characteristics and fine wiring formability in a high frequency region, that is, adhesion between a metal layer having a high Q value and low roughness and a cured resin layer. Another object of the present invention is to provide an excellent metal-cured resin laminate.

In view of the above problems, the present inventors have intensively studied a method for improving the adhesion between the cured resin layer and the metal layer having a low surface roughness. As a result, the surface of the metal layer having a low roughness is treated with a radical-reactive carbon-carbon non-reactive layer. When a curable resin composition layer containing a conjugated diene polymer and a curing agent is formed on the surface of the metal layer after being treated with a silane coupling agent having a saturated group and then thermally cured (crosslinked), the Q value is high, and It has been found that a metal-cured resin laminate having high adhesion between a metal layer having a low roughness and a cured resin layer can be obtained for the first time. It has also been found that according to this method, it is possible to obtain an adhesion strength of 0.5 kN / m or more even if the thickness and roughness of the metal layer are reduced to the limit. Furthermore, when a metal-cured resin laminate obtained by the present invention and having a high Q value and excellent adhesion to a low-roughness metal layer is used, a circuit board having L / S = 20 μm or less can be easily produced. Further, when a circuit board such as a microstrip line was produced and the transmission loss at 1 to 10 GHz was measured, it was found that the value was extremely small. Based on these findings, the inventors have completed the present invention.

Thus, according to the present invention, there is provided a metal-cured resin laminate having a metal layer and a cured conjugated diene polymer layer, wherein the roughness of the adhesive surface of the metal layer to the cured conjugated diene polymer layer (Rz) is 2, Provided is a metal-cured resin laminate having an adhesion strength between the metal layer and the cured conjugated diene polymer layer of 0.5 kN / m or more at 500 nm or less.

According to the present invention, it is possible to easily obtain a metal-cured resin laminate having a high Q value and excellent adhesion between a metal layer having a low roughness and a cured resin layer. In addition, since the metal-cured resin laminate of the present invention has a high Q value and excellent adhesion between the metal layer having a low roughness and the cured resin layer, the metal-cured resin laminate has a high frequency such as microwave or millimeter wave for use in communication equipment. It can be suitably used for a circuit board. Further, since the metal-cured resin laminate of the present invention is excellent in adhesion between the metal layer having a low roughness and the cured resin layer, the L / S can be reduced, the Q value is high, and the circuit board is small. be able to.

硬化 The cured conjugated diene polymer used in the present invention is a cured product of a conjugated diene polymer. As this polymer, what hardened | cured the curable resin composition containing a conjugated diene polymer and a hardening | curing agent is used normally. The cured resin in the metal-cured resin laminate of the present invention comprises a cured conjugated diene polymer.

(Conjugated diene polymer)
The conjugated diene polymer used in the present invention is a polymer containing at least a conjugated diene monomer unit. The polymer is not particularly limited, but at least one selected from the group consisting of a conjugated diene homopolymer and a conjugated diene copolymer is preferably used. These synthesis methods are not particularly limited.

Examples of the conjugated diene monomer include butadiene, isoprene, chloroprene, pentadiene and the like, preferably butadiene and isoprene, and more preferably butadiene.

Examples of the conjugated diene homopolymer include polybutadiene, polyisoprene, polychloroprene, polycyanobutadiene, polypentadiene, and the like, preferably polybutadiene, polyisoprene, and more preferably polybutadiene.

The conjugated diene copolymer is not particularly limited as long as it is a copolymer containing at least a conjugated diene monomer unit. For example, a random copolymer or a block copolymer can be used. When a conjugated diene copolymer is used, if the cured conjugated diene polymer layer contains reinforcing fibers, the cured resin impregnation into the reinforcing fibers and the adhesion strength, mechanical strength, toughness, etc. of the resulting metal-cured resin laminate These characteristics are highly balanced and suitable.

Examples of the monomer copolymerizable with the conjugated diene monomer in the conjugated diene copolymer include, for example, a cyano group-containing vinyl monomer, an amino group-containing vinyl monomer, a pyridyl group-containing vinyl monomer, an alkoxyl group-containing vinyl monomer, and an aromatic vinyl monomer. Among these, cyano group-containing vinyl monomers and aromatic vinyl monomers are preferable, and aromatic vinyl monomers are particularly preferable.

Examples of the aromatic vinyl monomer include styrene, α-methyl styrene, 2-methyl styrene, 3-methyl styrene, 4-methyl styrene, 2,4-diisopropyl styrene, 2,4-dimethyl styrene, and 4-t-butyl. Examples include styrene, 5-t-butyl-2-methylstyrene, N, N-dimethylaminoethylstyrene, N, N-diethylaminoethylstyrene, and among these, styrene and α-methylstyrene are particularly preferable. .

The blending ratio of the conjugated diene monomer unit and the copolymerizable monomer unit of the conjugated diene copolymer is appropriately selected according to the purpose of use, and is usually 95 by weight ratio of the conjugated diene monomer unit / the copolymerizable monomer unit. / 5 to 5/95, preferably 90/10 to 10/90, more preferably 80/20 to 20/80, and within this range, the adhesion strength and mechanical strength of the metal-cured resin laminate And toughness properties are highly balanced and suitable.

The coupling mode of the conjugated diene block copolymer used as the conjugated diene copolymer is appropriately selected according to the purpose of use, such as a 2-block copolymer, a 3-block copolymer, a 4-block copolymer, and a 5-block copolymer. Although selected, the use of a triblock copolymer is preferable because the relationship between the laminate property of the metal layer and the cured conjugated diene polymer layer and the mechanical strength of the resulting laminate is highly balanced. Specific examples include styrene-butadiene-styrene block polymers, styrene-isoprene-styrene block polymers, α-methylstyrene-butadiene-α-methylstyrene block polymers, and preferably styrene-butazine-styrene block polymers. .

The vinyl bond amount of the conjugated diene part of the conjugated diene polymer used in the present invention is appropriately selected according to the purpose of use, but it is determined using a Hampton method (R. Hampton, Anal. Chem., Using an infrared spectrophotometer). 21, 923 (1949)), usually 5 mol% or more, preferably 40 mol% or more, more preferably 60 mol% or more, most preferably 80 mol% or more. When the vinyl bond content is within this range, the adhesion strength and mechanical strength of the metal-cured resin laminate can be improved to a high degree, which is preferable.

The molecular weight of the conjugated diene polymer used in the present invention can be appropriately selected depending on the purpose of use, but it is a weight average molecular weight measured by gel permeation chromatography (polystyrene conversion, toluene eluent), usually 500 to 5, It is in the range of 1,000,000, preferably 1,000 to 1,000,000.

In the present invention, each of the conjugated diene polymers can be used alone or in combination of two or more kinds. By combining the conjugated diene homopolymer and the conjugated diene copolymer, the adhesion strength of the metal-cured resin laminate can be obtained. The mechanical properties and toughness properties are highly balanced and suitable.

When the conjugated diene homopolymer and the conjugated diene copolymer are combined, the molecular weight of the conjugated diene homopolymer is a weight average molecular weight measured by gel permeation chromatography (polystyrene conversion, toluene eluent), usually 500 to 500, 000, preferably 1,000 to 10,000, more preferably 1,000 to 5,000. When combined, the molecular weight of the conjugated diene copolymer is a weight average molecular weight measured by gel permeation chromatography (polystyrene conversion, toluene eluent), and is usually 1,000 to 1,000,000, preferably 5, The range is from 000 to 500,000, more preferably from 10,000 to 300,000. When the molecular weight of the conjugated diene homopolymer and the conjugated diene copolymer is within this range, the adhesion strength and mechanical strength of the metal-cured resin laminate, particularly when the reinforcing fiber is used in the curable resin composition, The mechanical strength is highly balanced and suitable.

The blending ratio in the case of combining the conjugated diene homopolymer and the conjugated diene copolymer is appropriately selected according to the purpose of use, but is usually 10/90 to 95 in terms of the weight ratio of the conjugated diene homopolymer / conjugated diene copolymer. / 5, preferably 50/50 to 90/10, more preferably in the range of 70/30 to 85/15. When the ratio of the two is within this range, the adhesion strength, mechanical properties, and toughness properties of the metal-cured resin laminate are highly balanced, which is preferable.

(Curing agent)
The curing agent used in the present invention is not particularly limited as long as it can induce the curing reaction of the conjugated diene polymer, but a radical generator is usually used. Examples of the radical generator include organic peroxides, diazo compounds, and nonpolar radical generators, with organic peroxides and nonpolar radical generators being preferred. In particular, a nonpolar radical generator is preferred in order to increase the Q value to a high degree and to improve the adhesion between the metal layer and the cured conjugated diene polymer layer.

Examples of the organic peroxide include hydroperoxides such as t-butyl hydroperoxide, p-menthane hydroperoxide, cumene hydroperoxide; dicumyl peroxide, t-butylcumyl peroxide, α, α'-bis (t- Butylperoxy-m-isopropyl) benzene, di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) -3-hexyne, 2,5-dimethyl-2,5-di ( dialkyl peroxides such as t-butylperoxy) hexane; diacyl peroxides such as dipropionyl peroxide and benzoyl peroxide; 2,2-di (t-butylperoxy) butane, 1,1-di (t-hexylperoxy) cyclohexane, 1,1-di (t-butylperoxy) -2- Peroxyketals such as tilcyclohexane and 1,1-di (t-butylperoxy) cyclohexane; peroxyesters such as t-butylperoxyacetate and t-butylperoxybenzoate; t-butylperoxyisopropylcarbonate, di (isopropylperoxy) ) Peroxycarbonates such as dicarbonate; alkylsilyl peroxides such as t-butyltrimethylsilyl peroxide; and the like. Of these, dialkyl peroxides and peroxyketals are preferable.

Examples of diazo compounds include 4,4'-bisazidobenzal (4-methyl) cyclohexanone and 2,6-bis (4'-azidobenzal) cyclohexanone.

Nonpolar radical generators include 2,3-dimethyl-2,3-diphenylbutane, 3,4-dimethyl-3,4-diphenylhexane, 1,1,2-triphenylethane, 1,1,1- And triphenyl-2-phenylethane.

When the curing agent used in the present invention is a radical generator, the one-minute half-life temperature is appropriately selected depending on the type of radical generator and the use conditions, but is usually 50 to 350 ° C., preferably 100 to 250 ° C. More preferably, it is in the range of 150 to 230 ° C. Here, the half-life temperature for 1 minute is a temperature at which half of the radical generator decomposes in 1 minute. For example, it is 186 ° C. for di-t-butyl peroxide and 194 ° C. for 2,5-dimethyl-2,5-bis (t-butylperoxy) -3-hexyne.

These curing agents can be used alone or in combination of two or more. The amount of the curing agent used is usually in the range of 0.01 to 10 parts by weight, preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the conjugated diene polymer. .

The curable resin composition used in the present invention contains the conjugated diene polymer and a curing agent as essential components, and optionally contains a filler, an antioxidant, a curing aid, a reinforcing fiber, and other compounding agents. Can be added.

In the present invention, it is preferable to add a filler to the curable resin composition because the mechanical strength of the metal-cured resin laminate can be improved and the thermal expansion coefficient can be reduced. The filler is not particularly limited as long as it is generally used industrially, and either an inorganic filler or an organic filler can be used, but an inorganic filler is preferred.

Examples of the inorganic filler include metal particles such as iron, copper, nickel, gold, silver, aluminum, lead, and tungsten; carbon particles such as carbon black, graphite, activated carbon, and carbon balloon; silica, silica balloon, alumina, and oxidation. Inorganic oxide particles such as titanium, iron oxide, zinc oxide, magnesium oxide, tin oxide, beryllium oxide, barium ferrite and strontium ferrite; inorganic carbonate particles such as calcium carbonate, magnesium carbonate and sodium hydrogen carbonate; inorganic such as calcium sulfate Sulfate particles: inorganic silicate particles such as talc, clay, mica, kaolin, fly ash, montmorillonite, calcium silicate, glass, glass balloon; calcium titanate, strontium titanate, barium titanate, lead zirconate titanate Titanium etc. Examples thereof include acid salt particles, aluminum nitride, silicon carbide particles and whiskers.

Examples of organic fillers include compound particles such as wood powder, starch, organic pigments, polystyrene, nylon, polyolefins such as polyethylene and polypropylene, vinyl chloride, various elastomers, and waste plastics.

Among these, the Q value can be increased, and inorganic oxide particles are preferable, and specific examples include titanate particles such as silica, alumina, calcium titanate, strontium titanate, and barium titanate. These fillers can be used alone or in combination of two or more, and the compounding amount is usually 1 to 1,000 parts by weight, preferably 10 to 100 parts by weight with respect to 100 parts by weight of the conjugated diene polymer. The amount is in the range of 500 parts by weight, more preferably 50 to 350 parts by weight.

In the present invention, the curable resin composition has at least one selected from the group consisting of a phenolic anti-aging agent, an amine-based anti-aging agent, a phosphorus anti-aging agent and a sulfur-based anti-aging agent as an anti-aging agent. By adding an anti-aging agent, the heat resistance of the resulting metal-cured resin laminate can be highly improved without inhibiting the curing reaction, which is preferable. Among these, a phenolic antiaging agent and an amine antiaging agent are preferable, and a phenolic antiaging agent is particularly preferable. These anti-aging agents can be used alone or in combination of two or more. The amount of the antiaging agent used is appropriately selected depending on the purpose of use, but is usually 0.0001 to 10 parts by weight, preferably 0.001 to 5 parts by weight, more preferably 100 parts by weight of the conjugated diene polymer. Is in the range of 0.01 to 1 part by weight.

In the present invention, the addition of a curing aid to the curable resin composition is preferable because the adhesion strength and mechanical strength of the metal-cured resin laminate can be highly balanced. The curing aid is a bifunctional or higher functional compound that can form a crosslinked structure. As the curing aid, commonly used ones can be used without particular limitation. For example, a bifunctional compound having two carbon-carbon unsaturated bonds, a polyfunctional compound having three or more carbon-carbon unsaturated bonds. Can be mentioned.

Specific examples of the curing aid include bifunctional compounds such as p-diisopropenylbenzene, m-diisopropenylbenzene and o-diisopropenylbenzene, trifunctionality such as triisopropenylbenzene and trimethallyl isocyanate. Compounds and the like. Of these, triisopropenylbenzene, p-diisopropenylbenzene, m-diisopropenylbenzene, and o-diisopropenylbenzene are preferable, and m-diisopropenylbenzene is more preferable.

硬化 These curing aids can be used alone or in combination of two or more. The amount of the curing aid is appropriately selected according to the purpose of use, but is usually 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, more preferably 100 parts by weight of the conjugated diene polymer. 1 to 20 parts by weight, most preferably 5 to 15 parts by weight.

In the present invention, it is preferable that the curable resin composition contains reinforcing fibers because the mechanical strength and toughness of the metal-cured resin laminate can be improved to a high degree. The reinforcing fiber is not particularly limited. For example, PET (polyethylene terephthalate) fiber, aramid fiber, ultra-high molecular polyethylene fiber, polyamide (nylon) fiber, liquid crystal polyester fiber, polyparabenzoxazole fiber, fluororesin fiber, etc. Organic fibers such as glass fibers, carbon fibers, alumina fibers, tungsten fibers, molybdenum fibers, budene fibers, titanium fibers, steel fibers, boron fibers, silicon carbide fibers, silica fibers, and the like. Among these, organic fibers and glass fibers are preferable, and aramid fibers, liquid crystal polyester fibers, and glass fibers are particularly preferable. As the glass fiber, fibers such as E glass, NE glass, S glass, D glass, NCR glass, and H glass can be suitably used.

These reinforcing fibers can be used singly or in combination of two or more, and the amount used is appropriately selected according to the purpose of use, but is usually 10 by weight ratio of conjugated diene polymer / reinforcing fiber. / 90 to 90/10, preferably 20/80 to 80/20, and more preferably 30/70 to 70/30. When in this range, the Q value and mechanical properties of the metal-cured resin laminate The strength is highly balanced and suitable.

Examples of other compounding agents include flame retardants, colorants, light stabilizers, pigments, and foaming agents. Examples of the flame retardant include phosphorus flame retardants, nitrogen flame retardants, halogen flame retardants, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, and antimony compounds such as antimony trioxide. As the colorant, dyes, pigments and the like are used. There are various kinds of dyes, and known ones may be appropriately selected and used. These other additives can be used alone or in combination of two or more, and the amount used is appropriately selected within a range not impairing the effects of the present invention.

(Metal layer)
The metal layer used in the present invention has a ten-point average roughness (Rz) measured according to JIS B0601-1994, and the roughness of the adhesive surface with the cured conjugated diene polymer layer is 2,500 nm or less. . According to the present invention, a metal-cured resin laminate having high adhesion can be obtained using a metal layer having low roughness. The roughness (Rz) of the adhesion surface of the metal layer to the cured conjugated diene polymer layer is preferably 2,000 nm or less, more preferably 1,800 nm or less, and most preferably 1,000 nm or less. On the other hand, the lower limit of the roughness is not particularly limited, but is usually 1 nm or more, preferably 5 nm or more, more preferably 10 nm or more. If the roughness of the metal layer is excessively large, it may cause noise, delay, transmission loss, etc. in high frequency transmission.
The roughness (Rz) of the adhesion surface of the metal layer incorporated in the metal-cured resin laminate with the cured conjugated diene polymer layer was obtained by dissolving and removing the metal layer with an appropriate chemical. By obtaining the roughness (Rz) of the adherend surface of the metal layer of the cured conjugated diene polymer layer as the ten-point average roughness (Rz) measured based on JIS B0601-1994, the roughness of the adherend surface is obtained. The degree (Rz) can be obtained indirectly. The roughness (Rz) of the adherend surface is the ten-point average roughness (Rz) measured based on JIS B0601-1994 as the roughness (Rz) of the adhesion surface of the metal layer to the cured conjugated diene polymer layer. It is substantially the same as the value measured directly. As a chemical for dissolving and removing the metal layer, for example, when the metal layer is a copper foil, an etching solution such as ferric chloride solution, sulfuric acid, sulfuric acid and hydrogen peroxide, and ammonium peroxodisulfate solution may be used. it can. What is necessary is just to select suitably the chemical | medical agent for melt | dissolving and removing a metal layer according to the material of a metal layer.

As a material for the metal layer, those generally used for circuit boards can be used without particular limitation, and usually metal foil, preferably copper foil is used.

The thickness of the metal layer used in the present invention is appropriately selected according to the purpose of use, but is usually in the range of 1 to 50 μm, preferably 3 to 30 μm, more preferably 5 to 20 μm, and most preferably 5 to 15 μm. It is. If the thickness of the metal layer is excessively large, the L / S of the circuit board cannot be reduced. Conversely, if the thickness is excessively small, it may be difficult to form a stable circuit.

(Metal-cured resin laminate)
The metal-cured resin laminate of the present invention is formed by forming the cured conjugated diene polymer layer on the surface of the metal layer having a low roughness, and has a high Q value and high adhesion between the metal layer and the cured conjugated diene polymer layer. Have

The dielectric constant of the cured conjugated diene polymer layer of the metal-cured resin laminate of the present invention is appropriately selected depending on the purpose of use, but is a value measured at 5 GHz, usually 1.5 to 15, preferably 2 to 10, more preferably in the range of 2.5 to 7.5.

The Q value of the cured conjugated diene polymer layer of the metal-cured resin laminate of the present invention is the reciprocal of the dielectric loss tangent (1 / tan δ) measured at 5 GHz, usually 100 or more, preferably 300 or more, more preferably 500 or more. It is. When the Q value is excessively small, the high-frequency circuit tends to lack loss and reliability. The Q value of the cured conjugated diene polymer layer can be easily adjusted by appropriately using at least one selected from the group consisting of a conjugated diene homopolymer and a conjugated diene copolymer.

The adhesion strength between the metal layer of the metal-cured resin laminate of the present invention and the cured conjugated diene polymer layer is 0 when the roughness (Rz) of the adhesive surface between the metal layer and the cured conjugated diene polymer layer is 2500 nm or less. 0.5 kN / m or more, preferably 0.55 kN / m or more, more preferably 0.6 kN / m or more. The upper limit is not particularly limited and is determined by the thickness and roughness of the metal layer, but is usually 5 kN / m or less, preferably 3 kN / m or less, more preferably 2 kN / m or less. In particular, the adhesion strength when the roughness (Rz) of the adhesion surface between the metal layer and the cured conjugated diene polymer layer is 2,500 nm or less and the thickness of the metal layer is in the range of 5 to 15 μm is usually When the range is 0.5 to 5 kN / m, preferably 0.55 to 3 kN / m, more preferably 0.6 to 2 kN / m, the L / S of the circuit board can be reduced and transmission loss, delay, It is preferable because problems such as noise can be minimized. The adhesion strength can be measured by the method described in Examples described later.

The production of the metal-cured resin laminate of the present invention having the above adhesion strength is not particularly limited, but may be a compound having a radical reactive group (hereinafter referred to as “radical reactive treating agent”). ), Preferably formula (1) R ¹ _m R ² _k MX _n (M represents Si, Ti, Al or Zr, R ¹ represents a hydrocarbon group having an unsaturated bond, R ² represents an oxygen atom, nitrogen Represents a hydrocarbon group which may contain an atom, phosphorus atom, sulfur atom or halogen atom, X represents an alkoxyl group, acetoxy group, halogen atom, amino group, hydroxyl group or hydrogen atom, and m represents an integer of 1 or more. K represents an integer of 0 or more, n represents an integer of 1 or more, m + n + k is 4 when M is Si, Ti or Zr, and 3 when M is Al.) Compound or its It can be easily carried out by forming a curable resin composition layer comprising a conjugated diene polymer and a curing agent on the surface of the metal layer surface-treated with the compound, and then curing the curable resin composition. . About a metal layer and a curable resin composition, the thing similar to the above can be used.

Here, in the formula (1), the carbon number of the hydrocarbon group represented by R ¹ is usually 2 to 50. Specific examples of R ¹ include an alkenyl group, an alkynyl group, and a cycloalkyl group or an aryl group having an alkenyl group as a substituent. Specific examples include a vinyl group, an allyl group, a butenyl group, a decenyl group, a norbornyl group, a cyclohexenyl group, and a styryl group, and a styryl group is preferable.

The carbon number of the hydrocarbon group for R ² is usually 1 to 50. Specific examples of R ² include alkyl groups such as methyl group, ethyl group, and cyclohexyl group; aryl groups such as phenyl group and naphthyl group; alkyl groups or aryl groups having a thiol group, mercapto group, ether bond, or amide group An alkyl group such as a methyl group, an ethyl group or a cyclohexyl group; an aryl group such as a phenyl group is preferred.

Specific examples of X include alkoxyl groups such as methoxy group and ethoxy group; acetoxy group; halogen atom such as chlorine atom; amino group; hydroxyl group; Among these, alkoxy groups such as methoxy and ethoxy groups; acetoxy groups; halogen atoms such as chlorine atoms; amino groups; hydrogen atoms are preferred, alkoxyl groups such as methoxy groups and ethoxy groups; halogen atoms such as chlorine atoms; amino Group is more preferable, and alkoxyl groups such as methoxy group and ethoxy group are most preferable. In general, the alkoxyl group has 1 to 10 carbon atoms, and the acetoxy group has 2 to 10 carbon atoms.

Specifically, M is Si, Ti, Al or Zr, and Si is preferable.

Specific examples of the compound represented by the formula (1) include allyltrimethoxysilane, 3-butenyltrimethoxysilane, styryltrimethoxysilane, styryltriethoxysilane, allyltrichlorosilane, allylmethyldichlorosilane, styryltrichlorosilane, Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltris (2-methoxyethoxy) silane, vinyltrichlorosilane, n-decenyltrimethoxysilane, norbornyltrimethoxysilane, norbornyltriethoxysilane, Norbornyltrichlorosilane, cyclohexenyltrimethoxysilane, undecenyltrimethoxysilane, 3- (N-styrylmethyl-2-aminoethylamino) -propyltrimethoxysilane hydrochloride , Styrylethyltrimethoxysilane, 3- (N-styrylmethyl-2-aminoethylamino) -propyltrimethoxylane), vinylbenzyltrimethoxysilane, cyclohexenylethyltrimethoxysilane, 3-cyclopentadienyltrimethoxy Examples include lanthanum, cyclopentadienylpropyltrimethoxysilane, undecenyltrimethochlorosilane, cyclohexenylethyltrichlorosilane, norbornyltrichlorosilane, and the like.

The condensate of the compound represented by Formula (1) has a structure in which two or more molecules of the compound represented by Formula (1) are condensed at the X position. Specific examples include silazanes such as 1,3-divinyltetramethyldisilazane and siloxanes.

として Preferred examples of these radical-reactive treatment agents include styryltrimethoxysilane, styryltriethoxysilane, and styryltrichlorosilane.

These radical-reactive treatment agents can be used alone or in combination of two or more, and the amount used is appropriately selected according to the purpose of use, but the metal layer treated with the radical-reactive treatment agent The X-ray intensity when the surface is measured by fluorescent X-ray analysis is usually in the range of 0.1 to 0.8 kcps, preferably 0.2 to 0.5 kcps. If the amount of radical reactive treating agent used is too small, the adhesion strength is not sufficient, and conversely if too large, the Q value tends to deteriorate.

The treatment of the surface of the metal layer with the radical reactive treating agent may be carried out in accordance with a conventional method. For example, the surface of the metal layer can be treated with an aqueous solution containing a radical reactive treating agent.

The concentration of the radical reactive treating agent in the aqueous solution containing the radical reactive treating agent is usually 0.0001% by weight or more, preferably 0.0001 to 10% by weight, more preferably 0.001 to 1% by weight, and most preferably 0.001% by weight. It is in the range of 01 to 0.1% by weight. If the radical-reactive treatment agent concentration is too thin, the effect of improving the adhesion is inferior. Conversely, if the concentration is too high, hydrolysis condensation tends to proceed.

The radical-reactive treating agent-containing aqueous solution is preferable because it can uniformly disperse the radical-reactive treating agent by including a surfactant. As the surfactant, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants and the like can be used. Among them, the nonionic surfactant suppresses ion migration as a circuit board. This is preferable.

Nonionic surfactants include, for example, polyoxyethylene alkyl ethers such as polyoxyethylene octyl ether and polyoxyethylene second alkyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene phenyl ether and the like. And polyoxyethylene alkylphenyl ethers, alkylcarbonyloxypolyoxyethylenes, aliphatic polyhydric alcohol esters, aliphatic polyhydric alcohol polyoxyethylenes, and aliphatic sucrose esters.

These surfactants can be used alone or in combination of two or more, and the amount used is usually from 0.0001 to 10% by weight in the concentration of the surfactant in the radical-reactive processing agent-containing aqueous solution. %, Preferably 0.001 to 1% by weight, more preferably 0.01 to 0.1% by weight.

The pH of the soot-radical reactive treating agent-containing aqueous solution is appropriately selected depending on the kind of treating agent to be used, but is usually in the range of 1 to 10, preferably 2 to 7, and more preferably 3 to 5. When the pH of the radical-reactive treatment agent is within this range, the condensation reaction of the radical-reactive treatment agent can be suppressed. Usually, organic acids such as acetic acid, formic acid, oxalic acid, citric acid, butyric acid, aqueous ammonia, etc. It can be adjusted with.

The method for treating the surface of the metal layer with the radical-reactive treatment agent-containing aqueous solution may be in accordance with a conventional method, for example, a method in which the metal layer is dipped in the radical-reactive treatment agent-containing aqueous solution and then dried and rolled onto the surface of the metal layer. A method of applying a radical-reactive treatment agent-containing aqueous solution using a coating device such as a coater, die coater, or gravure coater, followed by drying, and spraying and drying the aqueous solution containing a radical-reactive treatment agent on the metal layer surface using a spray device And the like. Drying after the treatment with the radical-reactive treating agent-containing aqueous solution is usually carried out under conditions of 100 to 200 ° C. and 1 to 60 minutes.

The method for forming the curable resin composition layer on the surface of the metal layer treated with such a radical reactive treating agent may be in accordance with a conventional method. For example, the curable resin composition is dissolved or dispersed in a solvent to form a metal. A method of applying to the surface of the layer and drying the solvent, a sheet obtained by dissolving or dispersing the curable resin composition in the solvent and then applying the solution to the substrate surface, and then drying the solvent, or dissolving or dispersing the curable resin composition in the solvent The prepreg that has been impregnated into the reinforcing fiber and dried with the solvent can be performed by, for example, pressure laminating on the surface of the metal layer. Although it does not specifically limit as said base material, For example, metal foil, a resin-made support film, a metal drum, a steel belt, a fluororesin belt etc. are mentioned.

Examples of the solvent for dissolving or dispersing the curable resin composition include xylene, toluene, methyl ethyl ketone, methyl isobutyl ketone, hexane, cyclohexane, octane, and terpene. Xylene is particularly preferable. The amount of the solvent used can be appropriately selected depending on the amount of the polymer, the type of reinforcing fiber, and the like, and the drying of the solvent is appropriately selected within a range in which the reaction of the curing agent does not occur.

The drying temperature is usually in the range of 50 to 250 ° C., preferably 100 to 200 ° C., more preferably 120 to 170 ° C. In particular, when a radical generator is used as the curing agent, it is usually 1 minute of the radical generator. The half-life temperature or less, preferably a temperature of 10 ° C. or less of a 1-minute half-life temperature, more preferably a temperature of 20 ° C. or less of a 1-minute half-life temperature. The drying time may be appropriately selected, but is usually in the range of 0.1 to 120 minutes, preferably 0.5 to 60 minutes, more preferably 1 to 20 minutes.

The wrinkle curing method may be in accordance with a conventional method and is appropriately selected according to the type of the curing agent, but is usually heat-cured. The curing temperature is a temperature at which crosslinking is caused by the curing agent. When a radical generator is used, the curing temperature is 1 minute half-life temperature or more, preferably 5 minutes or more higher than the 1-minute half-life temperature, more preferably 1 minute. The temperature is 10 ° C. or more higher than the half-life temperature. Usually, it is in the range of 0 to 250 ° C, preferably 100 to 250 ° C, more preferably 150 to 230 ° C. When the curing temperature is excessively high, the adhesion strength between the metal layer and the cured conjugated diene polymer layer tends to be inferior. The curing time is in the range of 0.1 to 180 minutes, preferably 1 to 120 minutes, more preferably 2 to 60 minutes.

The metal-cured resin laminate of the present invention can be patterned by any commonly used method, and can be mounted with passive / active components by any commonly used method to produce an electronic circuit board. . Although such an electronic circuit board is not particularly limited in use, it is preferably used for a high-frequency circuit such as an antenna, a server, a router, or a tester that requires low transmission loss.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In the examples and comparative examples, “part” and “%” are based on weight unless otherwise specified.

Each characteristic in an Example and a comparative example was measured and evaluated according to the following method.
(1) Surface roughness: The surface roughness of the copper foil was determined as 10-point average roughness (Rz) according to JIS B0601-1994.

(2) Q value: A Q value (1 / tan δ) at 5 GHz was measured by a triplate resonance method using a network analyzer, and evaluated according to the following criteria.
A: Q value is 500 or more B: Q value is 300 or more and less than 500 C: Q value is less than 300

(3) Adhesion strength: The peel strength of the metal foil in the metal-cured resin laminate was measured based on JIS C6481, and evaluated according to the following criteria.
A: 0.6 kN / m or more B: 0.5 kN / m or more, less than 0.6 kN / m C: 0.3 kN / m or more, less than 0.5 kN / m D: less than 0.3 kN / m

(4) Fine wiring formability: The metal foil of the metal-cured resin laminate was etched to form a wiring and evaluated according to the following criteria. Here, the fact that the wiring could not be formed means that the remainder of the copper foil is recognized on the resin surface after etching.
A: A 25/25 μm line and space (L / S) wiring was formed.
B: 30/30 μm line and space (L / S) wiring was formed.
C: 40/40 μm line and space (L / S) wiring was formed.
D: Wiring was not possible.

(5) Transmission loss: A microstrip line circuit board was prepared using a metal-cured resin laminate, and the transmission loss at 5 GHz was measured and evaluated according to the following criteria.
A: 0.3 dB / cm or less B: More than 0.3 dB / cm, 0.4 dB / cm or less C: More than 0.4 dB / cm

(6) Amount of radical-reactive treatment agent: The amount of the metal layer surface after treatment with the radical-reactive treatment agent is:
The X-ray intensity was measured by a fluorescent X-ray measuring device and obtained.

Example 1
<Preparation of radical-reactive treatment agent-containing aqueous solution>
Polyoxyethylene octylphenyl as a surfactant is a solution in which p-styryltrimethoxysilane (trade name: KBM-1403, manufactured by Shin-Etsu Silicone) is dissolved in methanol to a concentration of 50% as an aqueous solution containing a radical reactive treating agent. Ether (trade name: HS-210, manufactured by NOF Corporation) is added dropwise to an aqueous solution containing 0.06%, dissolved, adjusted with acetic acid so that the pH is 4, and the treatment agent concentration is 0.03. % Aqueous solution containing a radical reactive treating agent was obtained.

<Surface treatment of copper foil>
The above-obtained aqueous solution containing radical reactive treatment solution was added to a 12 μm thick F3 copper foil (electrolytic copper foil, roughness Rz = 2,100 nm, manufactured by Furukawa Circuit Foil Co., Ltd.) at room temperature using a bar coater. The coating was uniformly applied so that the coating thickness was 4 μm. Next, this was immediately dried at 120 ° C. for 5 minutes under a nitrogen stream to obtain a surface-treated copper foil. The amount of radical reactive treating agent on the copper foil was 0.339 kcps.

<Manufacture of metal-cured resin laminate>
Polybutadiene B3000 (manufactured by Nippon Soda Co., Ltd .; molecular weight 3000, 1,2-vinyl bond content 95 mol%) 100 parts, styrene-butadiene-styrene block polymer (styrene content 30%, molecular weight 70,000) 30 parts, bromine-based difficulty A curable resin composition was obtained by mixing 31 parts of a flame retardant Saytex BT-93WFG (manufactured by ALBEMARLE), 70 parts of silica, and 1.2 parts of a curing agent di-t-butyl peroxide in xylene. Next, the obtained curable resin composition was impregnated into glass cloth # 1080 (E glass manufactured by Asahi Sebel), and the solvent was removed by heating to prepare a prepreg. The glass fiber content of the prepreg was 40%.

Next, 5 sheets of the prepared prepreg sheets were stacked, and further, the electrolytic copper foil subjected to the surface treatment as described above was stacked on both sides so that the treated surface was in contact with the prepreg sheet, and this was heated at 200 ° C. for 10 minutes at 3 MPa. A metal-cured resin laminate was obtained by pressing. The obtained laminate was evaluated for Q value, adhesion strength, fine wiring moldability, and transmission loss. The results are shown in Table 1.

From the obtained metal-cured resin laminate, an adhesive portion between a cured conjugated diene polymer layer comprising polybutadiene and styrene-butadiene-styrene block polymer as a base resin and a metal layer comprising copper foil is obtained, The copper foil is dissolved and removed using a ferric chloride solution, and the roughness (Rz) of the adherend surface of the metal layer of the remaining cured conjugated diene polymer layer is measured based on JIS B0601-1994. When calculated as the point average roughness (Rz), the value is the ten-point average roughness measured based on the roughness (Rz) of the adhesion surface of the metal layer to the cured conjugated diene polymer layer in accordance with JIS B0601-1994. It was the same as the value (Rz = 2,100 nm) directly measured as (Rz). The same applies to Examples 2 to 4 below.

Example 2
As the copper foil, a metal-cured resin laminate was obtained in the same manner as in Example 1 except that a 12 μm thick F2 copper foil (electrolytic copper foil, roughness Rz = 1,600 nm, manufactured by Furukawa Circuit Foil Co., Ltd.) was used. Each characteristic was evaluated. The results are shown in Table 1.

Example 3
As the copper foil, a metal-cured resin laminate was obtained in the same manner as in Example 1 except that a 12 μm thick F0 copper foil (electrolytic copper foil, roughness Rz = 700 nm, manufactured by Furukawa Circuit Foil) was used. Evaluated. The results are shown in Table 1.

Example 4
A metal-cured resin laminate was obtained in the same manner as in Example 2 except that 2,3-dimethyl-2,3-diphenylbutane was used as the curing agent and the curing conditions were set at 220 ° C. for 60 minutes. evaluated. The results are shown in Table 1.

Comparative Example 1
A metal-cured resin laminate was obtained in the same manner as in Example 1 except that γ-mercaptopropyltrimethoxysilane was used as a treating agent, and each characteristic was evaluated. The results are shown in Table 1.

Comparative Example 2
Laminated metal-cured resin in the same manner as in Example 1 except that 12 μm thick F3 copper foil (electrolytic copper foil, roughness Rz = 2,100 nm, manufactured by Furukawa Circuit Foil Co., Ltd.) not treated with a radical reactive treating agent was used. A body was obtained and each characteristic was evaluated. The results are shown in Table 1.

Comparative Example 3
A metal-cured resin laminate in the same manner as in Example 1 except that a 12 μm thick F2 copper foil (electrolytic copper foil, roughness Rz = 1,600 nm, manufactured by Furukawa Circuit Foil Co., Ltd.) not treated with a radical reactive treating agent was used. A body was obtained and each characteristic was evaluated. The results are shown in Table 1.

Comparative Example 4
An untreated F3 copper foil having a thickness of 12 μm was used, and a 10% xylene solution of an ethylene-propylene-diene elastomer was prepared on the surface of the F3 copper foil according to Japanese Patent Publication No. 2005-502192. A solution obtained by adding 5 parts of 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 per part to a coating amount of 5.9 g / m ² and drying. A metal-cured resin laminate was obtained in the same manner as in Example 1 except that it was used, and each characteristic was evaluated. The results are shown in Table 1.

As can be seen from the above, according to the present invention, a metal-cured resin laminate having a high Q value and high adhesion between the metal layer having a low roughness and the cured conjugated diene polymer layer can be obtained. When the metal-cured resin laminate is used, fine wiring can be formed when manufacturing a circuit board, and the resulting circuit board has a small transmission loss.

Claims

A metal-cured resin laminate having a metal layer and a cured conjugated diene polymer layer, wherein the metal layer has a roughness (Rz) of an adhesive surface with the cured conjugated diene polymer layer of 2500 nm or less, A metal-cured resin laminate having an adhesion strength with a cured conjugated diene polymer layer of 0.5 kN / m or more.
The metal-cured resin laminate according to claim 1, wherein the cured conjugated diene polymer layer is formed by curing a curable resin composition comprising a conjugated diene polymer and a curing agent.
The metal-cured resin laminate according to claim 2, wherein the curable resin composition further comprises a curing aid.
The metal-cured resin laminate according to claim 2 or 3, wherein the curable resin composition further comprises reinforcing fibers.
The metal-cured resin laminate according to any one of claims 2 to 4, wherein the curable resin composition is cured by forming the curable resin composition layer on the surface of the metal layer which has been surface-treated with a radical reactive treating agent, and then performing the curing. .
The radical reactive treating agent has the formula (1) R 1 m R 2 k MX n (M represents Si, Ti, Al or Zr, R 1 represents a hydrocarbon group having an unsaturated bond, and R 2 represents oxygen An atom, a nitrogen atom, a phosphorus atom, a sulfur atom, or a hydrocarbon group that may contain a halogen atom, X represents an alkoxyl group, an acetoxy group, a halogen atom, an amino group, a hydroxyl group, or a hydrogen atom, and m is 1 or more. K represents an integer greater than or equal to 0, n represents an integer greater than or equal to 1. m + n + k is 4 when M is Si, Ti, or Zr, and 3 when M is Al. 6. The metal-cured resin laminate according to claim 5, which is a compound represented by the following formula or a condensate thereof.
The metal-cured resin laminate according to any one of claims 2 to 6, wherein the curing temperature is 0 to 250 ° C.
The metal-cured resin laminate according to any one of claims 1 to 7, wherein the metal layer has a thickness of 1 to 50 µm.
The metal-cured resin laminate according to any one of claims 1 to 8, wherein a Q value represented by (1 / dielectric loss tangent) of the cured conjugated diene polymer layer is 300 or more.
An electronic circuit board comprising the metal-cured resin laminate according to any one of claims 1 to 9.