JP2023068801A - Polyimide resin composition and cured product of the same - Google Patents

Abstract

To provide a copper foil with a resin having a resin layer which is composed of a resin composition, and a copper-clad laminate obtained by curing the resin layer that the copper foil with the resin has.SOLUTION: A copper foil with a resin has a resin layer composed of a resin composition on a roughened surface of a copper foil having surface roughness (Rz) of 1.1 μm or less or a non-roughened surface of a copper foil, wherein the resin composition contains an isocyanate-modified polyimide resin (D1) which is a reactant of a terminal functional group of an imidized product (C) of a polyamic acid resin that is a copolymer of an amino compound (A) containing an aliphatic diamino compound (a1) having 6 to 36 carbon atoms and an aromatic diamino compound (a2) and a tetrabasic acid dianhydride (B), and diisocyanate, or an isocyanate-modified terminal-modified polyimide resin (D2) which is a terminal modified product of the isocyanate-modified polyimide resin, silica (E) having a specific surface area in a BET method of 1.0-20 m2/g, a thermosetting resin (F) and a curing agent (G).SELECTED DRAWING: None

Description

The present invention relates to a resin-coated copper foil having a resin layer made of a thermosetting resin composition on the surface of the copper foil, and a copper-clad laminate obtained by curing the resin layer of the resin-coated copper foil.

BACKGROUND ART Printed wiring boards are indispensable members for electronic devices such as mobile communication devices such as smartphones and tablets, communication base station devices, computers and car navigation systems. 2. Description of the Related Art Various resin materials having excellent properties such as adhesion to metal foil, heat resistance and flexibility are used for printed wiring boards. In recent years, high-speed, large-capacity printed wiring boards for next-generation high-frequency radio have been developed. It is required to be tangent.

High-frequency electrical signals are used in communication equipment and electronic equipment for the purpose of transmitting and processing large amounts of information at high speed. A device to reduce the transmission loss is required. Transmission loss is roughly divided into conductor loss and dielectric loss. When the frequency of the electrical signal exceeds GHz, conductor loss depends on the surface condition of the copper foil used in the circuit. In general, it is preferable to use low-roughness or non-roughened copper foils, ie, low dielectric resins with high adhesion to these copper foils are desired.

Polyimide resins, which are excellent in properties such as heat resistance, flame retardancy, flexibility, electrical properties, and chemical resistance, are widely used in electrical and electronic parts, semiconductors, communication equipment and its circuit parts, peripheral equipment, and the like. In particular, soluble polyimide resins, whose solvent solubility has been improved by structural devising, etc., are easy to process and coat, and are used in a wide range because they do not require imidization processes that require high temperatures when used.
On the other hand, it is known that hydrocarbon compounds such as petroleum and natural oils exhibit high insulating properties and low dielectric constants.

Patent Documents 1 and 2 describe a resin composition containing a polyimide resin into which a dimer diamine skeleton having a long alkyl chain is introduced and a resin-coated copper foil using the same, and these resin compositions are Adhesion to copper foil and high solder heat resistance.
However, since further reduction in transmission loss is required in the high frequency region, it is necessary to reduce components such as epoxy resin that deteriorate dielectric properties. In addition, it is known that the transmission loss in the high-frequency region increases when the surface roughness of the copper foil increases. If the roughness of the resin composition becomes small, the adhesiveness of the resin composition to the copper foil is lowered.

Patent Document 3 describes an example in which silica is added to a polyimide resin into which a dimer diamine skeleton has been introduced in order to improve dielectric properties. However, the resin composition described in Patent Document 3 has a high epoxy resin content, and in addition to an insufficient effect of reducing dielectric properties, there is a problem that the amount of filler added is poor, so that the coating properties on copper foil are poor. there were.

In response to the above problem, Patent Document 4 describes that high dielectric properties are achieved by reducing the content of epoxy resin in the resin composition. However, since the composition of Patent Document 4 contains a low thermosetting resin content, the cured product has a low crosslink density and low heat resistance.

JP 2018-168369 A JP 2017-119361 A Japanese Patent Application Laid-Open No. 2019-173010 WO2020/071154

An object of the present invention is to provide a resin-coated copper foil having a resin layer made of a resin composition having excellent coatability, and a copper clad laminate obtained by curing the resin layer made of the resin composition of the resin-coated copper foil. To provide a copper-clad laminate which is a body, has excellent adhesiveness between a cured product of a resin layer and a copper foil, has good heat resistance of the cured product of the resin layer, and has excellent dielectric properties.

As a result of intensive studies, the present inventors found that a terminal-modified polyimide resin with a specific structure, silica having a specific specific surface area, thermosetting MEANS TO SOLVE THE PROBLEM It discovered that the copper foil with resin which has a resin layer which consists of a resin composition containing resin and a hardening|curing agent solves said subject, and completed this invention.
That is, the present invention
(1) A resin-coated copper foil having a resin layer made of a resin composition on the roughened surface of the copper foil or the surface of the non-roughened copper foil having a surface roughness (Rz) of 1.1 μm or less, wherein the resin composition Polyamic acid is a copolymer of an amino compound (A) containing an aliphatic diamino compound (a1) having 6 to 36 carbon atoms and an aromatic diamino compound (a2) and a tetrabasic dianhydride (B) An isocyanate-modified polyimide resin (D1) or an isocyanate-modified terminal-modified polyimide resin (D2) which is a reaction product of a terminal functional group and a diisocyanate possessed by the imidized product (C) of the resin, and a specific surface area in the BET method of 1.0 to 20 m ² /g of silica (E), a thermosetting resin (F) and a resin-coated copper foil containing a curing agent (G);
(2) The content of silica (E) is 5 to 50% by mass based on the solid content of the isocyanate-modified polyimide resin (D1) or the isocyanate-modified terminal-modified polyimide resin (D2) With the resin according to (1) Copper foil,
(3) The resin-coated copper foil according to (1) or (2) above, wherein the silica (E) has an average particle size of 0.30 to 5.0 μm;
(4) The resin-coated copper foil according to any one of (1) to (4) above, wherein the silica (E) is silica not surface-treated with a silane compound;
(5) Tetrabasic dianhydride (B) is represented by the following formulas (1) to (5)

(In formula (4), Y is C(CF ₃ ) ₂ , SO ₂ , CO, an oxygen atom, a direct bond, or the following formula (6)

Represents a divalent linking group represented by )
The resin-coated copper foil according to the preceding item (1), containing a compound selected from the group consisting of:
(6) the aromatic diamino compound (a2) is represented by the following formulas (7) to (10)

(In formula (9), R ₂ independently represents a methyl group or a trifluoromethyl group; in formula (10), Z is CH(CH ₃ ), SO ₂ , CH ₂ , O—C ₆ H ₄ — O, an oxygen atom, a direct bond, or the following formula (6)

_R3 independently represents a hydrogen atom, a methyl group, an ethyl group or a trifluoromethyl group. ) The resin-coated copper foil according to the preceding item (6) containing a compound selected from the group consisting of
(7) The resin-coated copper foil according to (6) above, wherein the thermosetting resin (F) contains an aromatic maleimide resin, and (8) Any one of (1) to (7) above. A copper-clad laminate obtained by curing a resin layer made of a resin composition possessed by the resin-coated copper foil of
Regarding.

Since the resin composition that forms the resin layer of the resin-coated copper foil of the present invention has excellent coatability, the resin-coated copper foil can be prepared by a simple method. In addition, the copper-clad laminate obtained by curing the resin layer composed of the resin composition of the resin-coated copper foil of the present invention has excellent adhesion between the cured resin layer and the copper foil, and the cured resin layer has excellent adhesion. Since it has good heat resistance and excellent dielectric properties, it can be suitably used for printed wiring boards and the like.

The present invention will be described in detail below.
In the resin-coated copper foil of the present invention, an aliphatic diamino compound (a1) having 6 to 36 carbon atoms is added to the roughened surface of a copper foil having a surface roughness (Rz) of 1.1 μm or less or the surface of a non-roughened copper foil. (hereinafter simply referred to as "(a1) component") and an amino compound (A) (hereinafter simply referred to as "(A ) component”) and tetrabasic dianhydride (B) (hereinafter also simply referred to as “(B) component”). An isocyanate-modified polyimide resin (D1) (hereinafter simply referred to as "(D1) component") or the isocyanate-modified polyimide resin (D1) which is a reaction product of a terminal functional group and a diisocyanate possessed by "imidated product (C)") or An isocyanate-modified terminal-modified polyimide resin (D2) (hereinafter also simply referred to as "(D2) component"), which is a terminal-modified polyimide resin, silica having a specific surface area in the BET method of 1.0 to 20 m ² /g (E) (hereinafter also simply referred to as “(E) component”), thermosetting resin (F) (hereinafter also simply referred to as “(F) component”) and curing agent (G) (hereinafter simply referred to as “component (F)”) (also referred to as "(G) component") containing a resin composition (hereinafter also simply referred to as "resin composition").
First, the imidized product (C), which is an intermediate raw material for the component (D1), will be described.

The component (a1) used in the synthesis of the imidized product (C) is not particularly limited as long as it is an aliphatic compound having 6 to 36 carbon atoms and having two amino groups in one molecule. The aliphatic structure in the component (a1) may be linear, branched or cyclic, or may have the above structures, and may be saturated or unsaturated. may
Specific examples of component (a1) include hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,3-bisaminomethylcyclohexane, norbornanediamine, isophoronediamine, dimerdiamine, 2-methyl-1,5 -diaminopentane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,4-bis (Aminomethyl)cyclohexane, 4,4'-methylenebiscyclohexylamine, diaminopolysiloxane having 6 to 36 carbon atoms, and the like. These may be used alone or in combination of two or more. From the viewpoint of the dielectric properties of the finally obtained component (D1) or component (D2), dimer diamine is preferably used.

The dimer diamine described in the specific examples of component (a1) is obtained by substituting primary amino groups for the two carboxyl groups of dimer acid, which is a dimer of unsaturated fatty acids such as oleic acid. See Japanese Laid-Open Patent Publication No. 9-12712, etc.). Specific examples of commercially available dimer diamines include PRIAMINE 1074 and PRIAMINE 1075 (both manufactured by Croda Japan Co., Ltd.) and Versamin 551 (manufactured by Cognis Japan Co., Ltd.). These may be used alone or in combination of two or more. Hereinafter, non-limiting general formulas of dimer diamines are shown (in each formula, m + n = 6 to 17 is preferable, p + q = 8 to 19 is preferable, and the broken line indicates a carbon-carbon single bond or a carbon-carbon double bond. means).

The amount of component (a1) used when synthesizing the polyamic acid resin that is an intermediate raw material for the imidized product (C) is, from the mass of component (A), the number of moles of water that is twice the number of moles of component (B). An amount in the range of 10 to 50% by mass of the mass obtained by dividing the mass of (the water produced by the dehydration condensation reaction) (the mass of the imidized product (C) produced) is preferable. If the amount of component (a1) is less than the above range, the amount of aliphatic chains derived from component (a1) in component (D1) or component (D2) finally obtained is too small, resulting in a cured product of the resin composition. If the dielectric loss tangent of becomes high and exceeds the above range, there are too many aliphatic chains derived from the (a1) component in the (D1) component or (D2) component, and the heat resistance of the cured product of the resin composition decreases.

Component (a2) used for synthesis of imidized product (C) is not particularly limited as long as it is an aromatic compound having two amino groups in one molecule and no phenolic hydroxyl group. When a diamino compound having a phenolic hydroxyl group is used, the reaction with the component (B) described later is slowed down, and there is a possibility that problems such as insufficient increase in the molecular weight of the imidized product (C) and deterioration of dielectric properties may occur. There is
Specific examples of component (a2) include m-phenylenediamine, p-phenylenediamine, m-tolylenediamine, 4,4′-diaminodiphenyl ether, 3,3′-dimethyl-4,4′-diaminodiphenyl ether, 3 , 4'-diaminodiphenyl ether, 4,4'-diaminodiphenylthioether, 3,3'-dimethyl-4,4'-diaminodiphenylthioether, 3,3'-diethoxy-4,4'-diaminodiphenylthioether, 3, 3'-diaminodiphenylthioether, 4,4'-diaminobenzophenone, 3,3'-dimethyl-4,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4' -diaminodiphenylmethane, 3,3′-dimethoxy-4,4′-diaminodiphenylthioether, 2,2′-bis(3-aminophenyl)propane, 2,2′-bis(4-aminophenyl)propane, 4, 4'-diaminodiphenylsulfoxide, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, benzidine, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine, 3,3′-diaminobiphenyl, p-xylylenediamine, m-xylylenediamine, o-xylylenediamine, 2,2′-bis(3-aminophenoxyphenyl)propane, 2,2′-bis(4- aminophenoxyphenyl)propane, 1,3-bis(4-aminophenoxyphenyl)benzene, 1,3′-bis(3-aminophenoxyphenyl)propane, bis(4-amino-3-methylphenyl)methane, bis( 4-amino-3,5-dimethylphenyl)methane, bis(4-amino-3-ethylphenyl)methane, bis(4-amino-3,5-diethylphenyl)methane, bis(4-amino-3-propyl phenyl)methane and bis(4-amino-3,5-dipropylphenyl)methane, and the like. These may be used alone or in combination of two or more.

The component (a2) used for the synthesis of the imidized product (C) has the following formulas (7) to (10) from the viewpoint of the heat resistance of the resin layer and the solubility in the solvent of the finally obtained polyimide resin. It preferably contains a compound selected from the group.

In formula (9), R ₂ independently represents a methyl group or a trifluoromethyl group, and in formula (10), Z is CH(CH ₃ ), SO ₂ , CH ₂ , O—C ₆ H ₄ —O , an oxygen atom, a direct bond or a divalent linking group represented by the following formula (6), and R ₃ independently represents a hydrogen atom, a methyl group, an ethyl group or a trifluoromethyl group.

The component (B) used for synthesizing the imidized compound (C) is not particularly limited as long as it has two acid anhydride groups in one molecule.
Specific examples of component (B) include pyromellitic anhydride, ethylene glycol-bis(anhydrotrimellitate), glycerin-bis(anhydrotrimellitate) monoacetate, 1,2,3,4,-butane Tetracarboxylic dianhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, 3,3′,4 ,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-diphenylethertetracarboxylic dianhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methylcyclohexene -1,2-dicarboxylic anhydride, 3a,4,5,9b-tetrahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3- dione, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, bicyclo(2,2,2)-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and bicyclo[ 2.2.2] octane-2,3,5,6-tetracarboxylic dianhydride, 5,5′-((propane-2,2-diylbis(4,1-phenylene))bis(oxy)) bis(isobenzofuran-1,3-dione), 4,4'-oxydiphthalic anhydride and the like. Among them, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride and 3,3′,4,4′-benzophenonetetracarboxylic acid are preferred in terms of solvent solubility and adhesion to substrates. dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride or 3,3′,4,4′-diphenylethertetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride preferable. These may be used alone or in combination of two or more.

The (B) component used for the synthesis of the imidized product (C) is the polyamic acid resin, the imidized product (C), and from the viewpoint of solvent solubility of the finally obtained (D1) component or (D2) component, the following formula It preferably contains a compound selected from the group consisting of (1) to (5).

In formula (4), Y represents C(CF ₃ ) ₂ , SO ₂ , CO, an oxygen atom, a direct bond, or a divalent linking group represented by formula (6) above.

When the number of moles of component (a1) in component (A) used for synthesis of polyamic acid resin is a1M and the number of moles of component (a2) is a2M, the value of a1M/(a1M+a2M) is 0.2. It is preferably greater than 0.9 and more preferably greater than 0.3 and less than 0.6. When a1M/(a1M+a2M) is 0.2 or less, the dielectric properties of the resin layer tend to deteriorate, and the solvent solubility of the resin layer tends to deteriorate. Moreover, when a1M/(a1M+a2M) is 0.9 or more, the heat resistance of the resin layer tends to deteriorate.

Also, the value of a2M/(a1M+a2M) is preferably more than 0.1 and less than 0.8, more preferably more than 0.2 and less than 0.6. When a2M/(a1M+a2M) is 0.1 or less, the soldering heat resistance of the cured product of the resin composition tends to deteriorate. Moreover, when a2M/(a1M+a2M) is 0.8 or more, the solvent solubility of the polyimide resin tends to deteriorate.

The number of moles of component (A) is MA, and the number of moles of component (B) is MB. A polyamic acid resin of the base polyamic acid resin is obtained. At this time, the value of MA/MB is preferably in the range of more than 1.0 and less than 10.0, more preferably more than 1.0 and less than 5.0. When the above value is 10.0 or more, in addition to insufficient increase in the molecular weight of the finally obtained polyimide resin, the residual rate of unreacted raw materials increases, and the heat resistance of the resin layer is deteriorated. Various characteristics may deteriorate.

The number of moles of component (A) is MA, and the number of moles of component (B) is MB. A polyamic acid resin of acid anhydride groups is obtained. At this time, the value of MB/MA is preferably in the range of over 1.0 and less than 10.0, more preferably in the range of over 1.0 and less than 5.0. If the above value is 10.0 or more, the finally obtained component (D1) or (D2) will not be sufficiently high in molecular weight, and the residual rate of unreacted raw materials will increase. Various properties such as heat resistance after curing of the resin layer may deteriorate.

A polyamic acid resin can be synthesized by a known method. For example, after dissolving the components (A) and (B) used in the synthesis in a solvent, the diamines and the tetrabasic dianhydrides are obtained by heating and stirring at 10 to 140°C under an inert atmosphere such as nitrogen. A copolymerization reaction with occurs to obtain a polyamic acid resin solution.

In addition, if necessary, a dehydrating agent or a catalyst is added to the polyamic acid resin solution obtained above, and the mixture is heated and stirred at 100 to 300° C. to cause an imidization reaction (ring-closure reaction accompanied by dehydration) to form the imidized product (C). can get. Toluene, xylene and the like can be used as dehydrating agents, and tertiary amines and dehydrating catalysts can be used as catalysts. Preferred tertiary amines are heterocyclic tertiary amines such as pyridine, picoline, quinoline, and isoquinoline. Dehydration catalysts include, for example, acetic anhydride, propionic anhydride, n-butyric anhydride, benzoic anhydride, and trifluoroacetic anhydride. The reaction time for synthesizing the polyamic acid resin and the polyimide resin is greatly affected by the reaction temperature, but it is preferable to carry out the reaction until the increase in viscosity accompanying the progress of the reaction reaches equilibrium and the maximum molecular weight is obtained. , usually from a few minutes to 20 hours.

The above example is a method of synthesizing a polyimide resin via a polyamic acid. The copolymerization reaction and the imidization reaction may be performed together by heating and stirring at 300° C. to obtain the imidized product (C).

Solvents that can be used in synthesizing the polyamic acid resin and in synthesizing the imidized product (C) include methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, methyl n-hexyl ketone, diethyl ketone, and diisopropyl. Ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, acetylacetone, γ-butyrolactone, diacetone alcohol, cyclohexene-1-one, dipropyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, tetrahydropyran, ethyl isoamyl ether, ethyl -t-butyl ether, ethyl benzyl ether, cresyl methyl ether, anisole, phenetole, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, amyl acetate, isoamyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, Methyl cyclohexyl acetate, benzyl acetate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, butyl propionate, benzyl propionate, methyl butyrate, ethyl butyrate, isopropyl butyrate, butyl butyrate, isoamyl butyrate, methyl lactate, lactic acid ethyl, butyl lactate, ethyl isovalerate, isoamyl isovalerate, diethyl oxalate, dibutyl oxalate, methyl benzoate, ethyl benzoate, propyl benzoate, methyl salicylate, N-methylpyrrolidone, N,N-dimethylformamide, Examples include, but are not limited to, N,N-dimethylacetamide, dimethylsulfoxide and the like. These may be used alone or in combination of two or more.

The preferred amount of the solvent to be used should be appropriately adjusted depending on the viscosity of the resin to be obtained and the intended use. be.

When synthesizing the imidized product (C), it is preferable to use a catalyst to promote the dehydration reaction. ), preferably 1 to 30%, more preferably 5 to 15%. Specific examples of usable catalysts include known basic catalysts such as triethylamine and pyridine. Among them, triethylamine is preferable because it has a low boiling point and does not easily remain.

Next, the (D) component, which is a reaction product between the terminal functional group of the imidized product (C) and the diisocyanate, will be described.
The reaction between the imidized product (C) and the diisocyanate is a copolymerization reaction between the terminal amino group and/or acid anhydride group of the imidized product (C) and the isocyanate group of the diisocyanate. A urea bond is formed by the reaction of , and an imide bond is formed by the reaction of an acid anhydride with an isocyanate group.
The amount of diisocyanate used is not particularly limited as long as the isocyanate group of the diisocyanate is less than 1 equivalent with respect to 1 equivalent of the terminal functional group of the imidized product (C). to 0.98 equivalents is more preferred. By setting the amount of diisocyanate to be used relative to the imidized product (C) within the above range, the finally obtained component (D1) or (D2) is sufficiently high in molecular weight, and unreacted raw materials remain. As a result, various properties such as heat resistance and flexibility after curing of the resin composition containing the polyimide resin or the like are improved.
The terminal functional equivalent of the imidized product (C) as used herein means a value calculated from the amount of each raw material used when synthesizing the imidized product (C).

The diisocyanate used in the synthesis of the component (D1) and the component (D2) can be any one having two isocyanate groups in one molecule. good too.
Diisocyanates include phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, tolidine diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, allylene sulfone ether diisocyanate, and allyl cyanate. Diisocyanates, N-acyl diisocyanates, trimethylhexamethylene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane or norbornane-diisocyanatomethyl are preferred. Among them, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, or isophorone diisocyanate is more preferable because of its excellent balance of flexibility, adhesiveness, and the like.

The reaction between the imidized product (C) and the diisocyanate may be carried out by a known synthetic method.
Specifically, the component (D1) can be obtained by adding a diisocyanate to the imidized product (C) obtained by the synthesis method described above and heating and stirring the mixture at 80 to 150°C. The reaction time for the synthesis reaction of the imidized product (C) and the reaction between the imidized product (C) and the diisocyanate is greatly affected by the reaction temperature. It is preferable to carry out the reaction until the maximum molecular weight is obtained, usually for several tens of minutes to 20 hours.

Component (D1) obtained above can be added to a poor solvent such as water, methanol and hexane to separate the resulting polymer, and then the solid content of component (D) can be obtained by reprecipitation.

Since component (D1) has amino groups and/or acid anhydride groups at both ends, it is a compound having one functional group capable of reacting with these functional groups (hereinafter simply referred to as "compound (J)" ) to modify the terminal to obtain component (D2). Examples of compounds that can react with an amino group and/or an acid anhydride group include compounds having an acid anhydride group such as maleic anhydride, compounds having an alcoholic hydroxyl group such as hydroxyethyl acrylate, and phenolic hydroxyl groups such as phenol. , compounds having an isocyanate group such as 2-methacryloyloxyethyl isocyanate, and compounds having an epoxy group such as glycidyl methacrylate.

By modifying the terminal with the compound (J), both terminals of the component (D1) can be changed to a functional group other than an amino group and an acid anhydride group (D2) component (for example, hydroxyethyl acrylate When terminal modification is performed using .

Compound (J) is not particularly limited as long as it is a compound having a functional group that reacts with the terminal functional group of component (D1). Those having both a functional group capable of reacting with the terminal functional group of the component (D1) and an ethylenically unsaturated double bond group are preferred, since heat resistance, mechanical properties and adhesiveness are improved.
Examples of functional groups capable of reacting with terminal functional groups of component (D1) include isocyanate groups, carboxylic acid chloride groups, acid anhydride groups, epoxy groups, silyl chloride groups, halogenated alkyl groups, ester groups, and sulfonyl chloride groups. and a carboxyl group, etc., but an isocyanate group is preferred in that residual impurities derived from a leaving group do not occur.
The ethylenically unsaturated double bond group possessed by compound (J) is not particularly limited as long as it is a C═C bond.

where MA is the number of moles of component (A), MB is the number of moles of component (B), and MI is the number of moles of isocyanate; And the component (D1) obtained by copolymerizing isocyanate has an amino group at the end, so that an isocyanate group, a carboxylic acid chloride group, an acid anhydride group, an epoxy group, a silyl chloride group, a halogenated alkyl group, an ester group, A compound (J) having a sulfonyl chloride group, a carboxyl group, or the like can react with the terminal amino group.

where MA is the number of moles of component (A), MB is the number of moles of component (B), and MI is the number of moles of isocyanate; And the component (D1) obtained by copolymerizing isocyanate has an acid anhydride group at the terminal, so the compound (J) having an isocyanate group, an epoxy group, a carboxyl group, or the like can react with the terminal acid anhydride group.

Specific examples of the compound (J) include Karenz MOI (manufactured by Showa Denko KK), Karenz AOI, Karenz MOI-BM, Karenz MOI-BP, Karenz BEI, Karenz MOI-EG, Karenz AOI-VM, methacrylic chloride, acrylic chloride, maleimidocaproic chloride, allyl bromide, allyl iodide, allyl chloride, 4-chloro-1-butene, 4-bromo-1-butene, crotonoyl chloride and cinnamoyl chloride;

Component (D2), which is a reaction product of component (D1) and compound (J), can be synthesized by a known method. For example, it can be synthesized by mixing a predetermined compound (J) with a resin solution of component (D1) and reacting the mixture at 80°C to 150°C.

Various catalysts may be used to promote the reaction between component (D) and compound (J). Known inorganic acids, organic acids, inorganic bases, organic bases and the like can be used as catalysts.

When the number of moles of the compound (J) used for the synthesis of the component (D2) is MJ and the number of moles of the terminal functional group of the component (D1) is MD, the value of MJ/MD is more than 0.3 and less than 1. and more preferably greater than 0.5 and less than 1. When MJ/MD is 1 or more, the unreacted compound (J) deteriorates the heat resistance of the cured product of the resin composition. Further, when MJ/MD is 0.3 or less, when the terminal functional group of component (D1) that does not react with compound (J) is an acid anhydride, substrate adhesion tends to decrease, and compound (J ) When the terminal functional group of the component (D1) that does not react with ) is an amine, the viscosity of the polyimide increases due to hydrogen bonding, and the lamination property tends to decrease, and the pot life of the composition with the thermosetting resin described later tends to decrease. be.

Next, the (E) component will be described.
The BET specific surface area of component (E) is preferably 1.0 to 20 m ² /g. By using the component (E) having a specific surface area within the above range, the dispersibility of the component (E) in the resin layer is improved, the flexibility of the cured product of the resin layer is improved, and the resin layer is cured. The adhesion strength between the silica and the cured product of the resin component is improved, and cohesive failure of the resin layer due to external stress is less likely to occur.

The content of component (E) in the resin composition that forms the resin layer of the resin-coated copper foil of the present invention is preferably 5 to 50% by mass, preferably 10 to 45% by mass, based on the solid content of component (D). and more preferably 15 to 35% by mass. By setting the content of the component (E) within the above range, the adhesion between the cured resin layer and the copper foil is improved, and the cured resin layer has increased flexibility.

The average particle size of component (E) is preferably 0.30 to 5.0 μm. By setting the average particle size of silica (E) within the above range, it is possible to reduce the inclusion of air bubbles in the resin layer, and the resin layer efficiently enters the unevenness of the copper foil to separate the cured product of the resin layer and the copper foil. improves adhesion.
In addition, the average particle size of the component (E) in the present specification means a value measured using a laser diffraction scattering type particle size distribution analyzer.

Component (E) is preferably not surface-treated with a silane compound. If the component (E) is surface-treated, the dispersibility is improved, but the effect of improving the heat resistance of the cured resin layer and the adhesion between the cured resin layer and the copper foil cannot be sufficiently obtained. There is

Component (E) is preferably spherical. In this case, the resin layer efficiently penetrates into the unevenness of the surface of the copper foil, and the adhesion between the cured resin layer and the copper foil can be further enhanced.

Next, the (F) component will be explained.
Specific examples of component (F) include epoxy resins, maleimide resins, carbodiimide resins, benzoxazine compounds and compounds having ethylenically unsaturated groups. These resins or compounds may be used alone or in admixture of two or more depending on the physical properties and application of the copper-clad laminate obtained by curing the resin layer of the resin-coated copper foil of the present invention. be able to.
In the present invention, by using component (F) in combination with component (D1) or component (D2), it is possible to impart thermal stability and high adhesiveness to the cured product of the resin layer composed of the resin composition. At that time, it is preferable that the terminal functional group (the terminal functional group after terminal modification) of the component (D1) or the component (D2) reacts with the component (F).

As the component (F), a maleimide resin or a compound having an ethylenically unsaturated group is preferable because the heat resistance and adhesiveness of the cured product of the resin composition are particularly excellent.
Incidentally, the number of moles of the component (A) used in the synthesis of the polyamic acid resin is MA, the number of moles of the component (B) is MB, the number of moles of the diisocyanate is MI, and the number of moles of the terminal functional group of the imide (C) is For polyimide resins in which the value of MA/MB exceeds 1 and the value of MI/MP exceeds 0 and is less than 1 when expressed as MP, it is also preferable to use an epoxy resin as the thermosetting resin. .

In addition, the component (F) preferably has a molecular weight of 100 to 50,000 from the viewpoint of suppressing an increase in viscosity when the resin composition is dissolved in a solvent to form a varnish. The term "molecular weight" as used herein means the weight-average molecular weight of a polystyrene standard determined by gel permeation chromatography (GPC).

The maleimide resin as component (F) is not particularly limited as long as it has two or more maleimide groups in one molecule.
Specific examples of maleimide resins having two or more maleimide groups in one molecule include tris- (4-aminophenyl)-phosphate, tris(4-aminophenyl)-phosphate, maleimide compound obtained by reaction of tos(4-aminophenyl)-thiophosphate with maleic anhydride, tris(4-maleimidophenyl)methane tetramaleimide compounds such as bis(3,4-dimaleimidophenyl)methane, tetramaleimidobenzophenone, tetramaleimidonaphthalene, maleimide obtained by the reaction of triethylenetetramine and maleic anhydride, phenol novolac type maleimide resins, isopropylidenebis(phenoxyphenylmaleimide)phenylmaleimide alkyl resins, biphenylene-type phenylmaleimide alkyl resins, etc. Commercially available products include MIR-3000, MIR-5000 (both manufactured by Nippon Kayaku Co., Ltd.), BMI- 70, BMI-80 (all manufactured by KI Kasei Co., Ltd.), BMI-1000, BMI-2000, BMI-3000 (all manufactured by Daiwa Kasei Kogyo Co., Ltd.), and the like.

In particular, a maleimide resin having an aromatic ring such as a benzene ring, a biphenyl ring and a naphthalene ring is preferable because the resin layer composed of a cured product of the resin composition is excellent in properties such as mechanical strength and flame retardancy. Examples thereof include MIR-3000 (manufactured by Nippon Kayaku Co., Ltd.) and MIR-5000 (manufactured by Nippon Kayaku Co., Ltd.).
The maleimide resin is added for the purpose of reacting with the ethylenically unsaturated double bond groups possessed by the component (D2), thereby increasing the cross-linking density of the resin layer composed of the cured product of the resin composition and resistance to the copper foil is improved, and adhesion to the copper foil and heat resistance are improved.
When the resin composition that forms the resin layer contains a maleimide resin, the curing temperature is preferably 150 to 250°C. The curing time depends on the curing temperature, but is generally several minutes to several hours.
The content of the maleimide resin in the resin composition for the resin layer is such that the maleimide group equivalent of the maleimide resin is 0.1 to 500 equivalents with respect to 1 equivalent of the ethylenically unsaturated double bond groups of the component (D2). is preferred.
In addition, the maleimide group equivalent in this specification means the theoretical maleimide equivalent calculated from the amine equivalent of the amine used as a raw material.

The epoxy resin as the component (F) is not particularly limited as long as it has two or more epoxy groups in one molecule. Epoxy resins having aromatic rings such as benzene rings, biphenyl rings and naphthalene rings are preferred because they are excellent in manufactured by Nippon Kayaku Co., Ltd.) and the like.
The epoxy resin is added for the purpose of reacting with the terminal amino group or acid anhydride group of the component (D1), thereby increasing the cross-linking density of the resin layer composed of the cured product of the resin composition and making it resistant to polar solvents. The resistance is improved, and the adhesion to the copper foil and heat resistance are improved.
The curing temperature of the resin composition containing the epoxy resin is preferably 150 to 250°C. The curing time depends on the curing temperature, but is generally several minutes to several hours.

When the resin composition for the resin layer contains an epoxy resin, the content of the epoxy resin is such that the epoxy group equivalent of the epoxy resin with respect to 1 equivalent of the active hydrogen of the terminal amino group and the terminal acid anhydride of the component (D1) is 0. .1 to 500 equivalents are preferred.
Incidentally, the epoxy group equivalent in this specification means the value measured by the method described in JIS K-7236.

The compound having an ethylenically unsaturated group as the component (F) is not particularly limited as long as it has one or more ethylenically unsaturated groups in one molecule.
Specific examples of compounds having an ethylenically unsaturated group include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate, polyethylene glycol (meth) acrylate, polyethylene glycol (meth) Acrylate monomethyl ether, phenylethyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate ) acrylate, neopentyl glycol di(meth)acrylate, nonanediol di(meth)acrylate, glycol di(meth)acrylate, diethylene di(meth)acrylate, polyethylene glycol di(meth)acrylate, tris(meth)acryloyloxyethyl isocyanurate , polypropylene glycol di(meth)acrylate, adipate epoxy di(meth)acrylate, bisphenol ethylene oxide di(meth)acrylate, hydrogenated bisphenol ethylene oxide (meth)acrylate, bisphenol di(meth)acrylate, ε-caprolactone-modified hydroxypivalic acid Neopen glycol di(meth)acrylate, ε-caprolactone-modified dipentaerythritol hexa(meth)acrylate, ε-caprolactone-modified dipentaerythritol poly(meth)acrylate, dipentaerythritol poly(meth)acrylate, trimethylolpropane tri(meth)acrylate ) acrylate, triethylolpropane tri(meth)acrylate and its ethylene oxide adduct; pentaerythritol tri(meth)acrylate and its ethylene oxide adduct; pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate , and ethylene oxide adducts thereof.

In addition to these, urethane (meth)acrylates having both a (meth)acryloyl group and a urethane bond in the same molecule; polyester (meth)acrylates having both a (meth)acryloyl group and an ester bond in the same molecule; epoxy Epoxy (meth) acrylates derived from resins and having (meth) acryloyl groups; reactive oligomers in which these bonds are used in combination are also specific examples of compounds having ethylenically unsaturated groups.

Urethane (meth)acrylates include reaction products of hydroxyl group-containing (meth)acrylates, polyisocyanates, and other alcohols used as necessary. For example, hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; ) acrylates; sugar alcohol (meth)acrylates such as pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; and toluene diisocyanate , hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, xylene diisocyanate, hydrogenated xylene diisocyanate, dicyclohexanemethylene diisocyanate, and their isocyanurates, burette reaction products, etc., reacted with polyisocyanates, etc., urethane ( meth)acrylates.

Polyester (meth)acrylates include, for example, caprolactone-modified 2-hydroxyethyl (meth)acrylate, ethylene oxide and/or propylene oxide-modified phthalic acid (meth)acrylate, ethylene oxide-modified succinic acid (meth)acrylate, caprolactone-modified tetrahydro Monofunctional (poly)ester (meth)acrylates such as furfuryl (meth)acrylate; hydroxypivalic acid ester neopentyl glycol di(meth)acrylate, caprolactone-modified hydroxypivalic acid ester neopentyl glycol di(meth)acrylate, epichlorohydrin-modified Di (poly) ester (meth) acrylates such as phthalic acid di (meth) acrylate; 1 mol or more of cyclic lactone compounds such as ε-caprolactone, γ-butyrolactone, and δ-valerolactone per 1 mol of trimethylolpropane or glycerin Mono-, di- or tri(meth)acrylates of adducted triols may be mentioned.

Also, a triol obtained by adding 1 mol or more of a cyclic lactone compound such as ε-caprolactone, γ-butyrolactone, or δ-valerolactone to 1 mol of pentaerythritol, dimethylolpropane, trimethylolpropane, or tetramethylolpropane. mono-, di-, tri-, or tetra-(meth)acrylates; mono-triols obtained by adding 1 mol or more of cyclic lactone compounds such as ε-caprolactone, γ-butyrolactone, and δ-valerolactone to 1 mol of dipentaerythritol, or Examples include mono(meth)acrylates or poly(meth)acrylates of polyhydric alcohols such as triols, tetraols, pentaols or hexaols of poly(meth)acrylates.

Furthermore, diol components such as (poly)ethylene glycol, (poly)propylene glycol, (poly)tetramethylene glycol, (poly)butylene glycol, 3-methyl-1,5-pentanediol, hexanediol, maleic acid, fumaric Polybasic acids such as acid, succinic acid, adipic acid, phthalic acid, isophthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, dimer acid, sebacic acid, azelaic acid, 5-sodium sulfoisophthalic acid, and anhydrides thereof (meth)acrylate of polyester polyol which is the reaction product of; (meth)acrylate of cyclic lactone-modified polyester diol composed of diol component, polybasic acid and their anhydrides and ε-caprolactone, γ-butyrolactone, δ-valerolactone, etc. and polyfunctional (poly)ester (meth)acrylates such as

Epoxy (meth)acrylates are carboxylate compounds of a compound having an epoxy group and (meth)acrylic acid. For example, phenol novolak type epoxy (meth)acrylate, cresol novolak type epoxy (meth)acrylate, trishydroxyphenylmethane type epoxy (meth)acrylate, dicyclopentadiene phenol type epoxy (meth)acrylate, bisphenol A type epoxy (meth)acrylate. , bisphenol F type epoxy (meth)acrylate, biphenol type epoxy (meth)acrylate, bisphenol A novolac type epoxy (meth)acrylate, naphthalene skeleton-containing epoxy (meth)acrylate, glyoxal type epoxy (meth)acrylate, heterocyclic epoxy ( meth)acrylates, and acid anhydride-modified epoxy acrylates thereof.

For example, vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, hydroxyethyl vinyl ether, and ethylene glycol divinyl ether; styrenes such as styrene, methylstyrene, ethylstyrene, and divinylbenzene; A compound having a vinyl group such as lunadiimide is also included as a specific example of the compound having an ethylenically unsaturated group.

As the compound having an ethylenically unsaturated group, commercially available products can be used. Propylene glycol monomethyl ether acetate (manufactured by Nippon Kayaku Co., Ltd., KAYARAD (registered trademark) ZCR-6007H (trade name), KAYARAD (registered trademark) ZCR-6001H (trade name), KAYARAD (registered trademark) ZCR-6002H (trade name) , and KAYARAD (registered trademark) ZCR-6006H (trade name) These compounds having an ethylenically unsaturated group can be used singly or in admixture of two or more.

The content of the compound having an ethylenically unsaturated group in the resin composition forming the resin layer is preferably 0.1 to 500 equivalents with respect to the ethylenically unsaturated double bond group equivalent of the component (D2).
In addition, the ethylenically unsaturated double bond group equivalent in this specification means the theoretical ethylenically unsaturated double bond group equivalent calculated from the raw material.

Next, the (G) component will be explained.
Component (G) is not particularly limited as long as it accelerates the curing reaction of component (F), and conventionally known curing agents for component (F) can be used. (G) A component may use only 1 type and may use 2 or more types together.

When the component (F) is a maleimide resin, known amino compounds, thiol compounds and radical initiators can be used as the component (G).
Specific examples of amino compounds include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, m-xylenediamine, trimethylhexamethylenediamine, 2-methylpentamethylenediamine, diethylaminopropylamine, isophoronediamine, and 1,3-bisaminomethyl. Cyclohexane, bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane, norbornenediamine, 1,2-diaminocyclohexane, diaminodiphenylmethane, metaphenylenediamine, diaminodiphenylsulfone, dicyandiamide, polyoxypropylene Diamine, polyoxypropylenetriamine, N-aminoethylpiperazine, aniline-formalin resin, etc., but not limited to these. These may be used alone or in combination of two or more.
When the resin composition that forms the resin layer contains a maleimide resin as the component (F), the amount of the amino compound added is preferably 5 times or less, more preferably 2 times or less, that of the component (F) in mass ratio. be.

Specific examples of thiol compounds include trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate), tetraethylene glycol bis (3-mercaptopropionate), and dipentaerythritol. Examples include, but are not limited to, hexakis(3-mercaptopropionate), tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanate, and the like. These may be used alone or in combination of two or more.
When the resin composition that forms the resin layer contains a maleimide resin as the component (F), the amount of the thiol compound added is preferably 5 times or less, more preferably 2 times or less, that of the component (F) by weight. be.

Specific examples of radical initiators include peroxides such as dicumyl peroxide and dibutyl peroxide, 2,2′-azobis(isobutyronitrile) and 2,2′-azobis(2,4-dimethylvalero nitrile) and other azo compounds, but are not limited to these. These may be used alone or in combination of two or more.
When the resin composition forming the resin layer contains a maleimide resin as the component (F), the amount of the radical initiator added is 0.1 to 10% by mass based on the maleimide resin.
In particular, from the viewpoint of reaction rate and dielectric properties, it is preferable to use a radical initiator.

When the (F) component is an epoxy resin, known imidazole compounds, phosphine compounds, phenolic resins and amino compounds can be used as the (G) component.
Specific examples of imidazole compounds and phosphine compounds include 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl- imidazoles such as 5-hydroxymethylimidazole, tertiary amines such as 2-(dimethylaminomethyl)phenol and 1,8-diaza-bicyclo(5,4,0)undecene-7, triphenylphosphine, etc. phosphines, metal compounds such as tin octylate, and the like, but are not limited to these. These may be used alone or in combination of two or more.
When the resin composition forming the resin layer contains an epoxy resin as the component (F), the amount of the imidazole compound or phosphine compound added is 0.1 to 10% by mass relative to the epoxy resin.

Specific examples of phenol resins include bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, etc.), phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl polycondensates of various aldehydes (formaldehyde, acetaldehyde, alkylaldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc.), Polymers of phenols and various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.), phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.), phenols and aromatic dimethanols (benzenedimethanol, α,α,α',α'-benzenedimethanol, biphenyldiethanol, Polycondensates with methanol, α,α,α',α'−biphenyldimethanol, etc.), Phenols and aromatic dichloromethyls polycondensates, polycondensates of bisphenols and various aldehydes, and modified products thereof, but are not limited thereto. These may be used alone or in combination of two or more.
When the resin composition that forms the resin layer contains an epoxy resin as the component (F), the amount of the phenol resin added is preferably 5 times or less, more preferably 2 times the weight of the component (F) with respect to the epoxy resin. It is in the range of less than double.

Specific examples of amino compounds include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, m− xylenediamine, trimethylhexamethylenediamine, 2-methylpentamethylenediamine, diethylaminopropylamine, isophoronediamine, 1,3&#8722. ; bisaminomethylcyclohexane, bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane, norbornenediamine, 1,2-diaminocyclohexane, diaminodiphenylmethane, metaphenylenediamine, diaminodiphenylsulfone, dicyandiamide , polyoxypropylenediamine, polyoxypropylenetriamine, N− aminoethylpiperazine, aniline-formalin resin, etc., but are not limited thereto. These may be used alone or in combination of two or more.
When the resin composition that forms the resin layer contains an epoxy resin as the component (F), the amount of the amine compound added is preferably 5 times or less, more preferably 2 times or less, that of the component (F) by weight. be.
From the viewpoint of dielectric properties, it is preferable to use an imidazole compound or a phosphine compound.

When component (F) is a compound having an ethylenically unsaturated group, it is preferred to use a radical initiator as component (G).
Specific examples of radical initiators include peroxides such as dicumyl peroxide and dibutyl peroxide, 2,2′-azobis(isobutyronitrile) and 2,2′-azobis(2,4-dimethylvalero nitrile) and other azo compounds, but are not limited to these. These may be used alone or in combination of two or more. When the resin composition that forms the resin layer contains a compound having an ethylenically unsaturated group, the amount of the radical initiator added is 0.1 to 10% by mass with respect to all ethylenically unsaturated groups in the composition. be.

A varnish-like composition (hereinafter simply referred to as varnish) can be obtained by using an organic solvent in combination with the resin composition that forms the resin layer.
Examples of solvents that can be used in combination include γ-butyrolactones, amide solvents such as N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide and N,N-dimethylimidazolidinone, and tetramethylenesulfone. sulfones, ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate and propylene glycol monobutyl ether, ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone and aromatic solvents such as toluene and xylene.
The organic solvent is used in such a range that the concentration of components other than the organic solvent in the varnish is preferably 10 to 80% by mass, more preferably 20 to 70% by mass.

You may use a well-known additive together with the resin composition used as a resin layer as needed.
Specific examples of additives that can be used in combination include polybutadiene or its modified product, modified acrylonitrile copolymer, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, maleimide compound, cyanate ester compound, silicone gel, and silicone. Oil, inorganic fillers such as alumina, calcium carbonate, quartz powder, aluminum powder, graphite, talc, clay, iron oxide, titanium oxide, aluminum nitride, asbestos, mica, glass powder, fillers such as silane coupling agents surface treatment agents, releasing agents, carbon black, phthalocyanine blue, phthalocyanine green and other coloring agents, aerosil and other thixotropic agents, silicone-based, fluorine-based leveling agents and antifoaming agents, hydroquinone, hydroquinone monomethyl ether, phenol-based Polymerization inhibitors, stabilizers, antioxidants, photopolymerization initiators, photobase generators, photoacid generators and the like can be mentioned. The amount of these additives is preferably 1,000 parts by mass or less, more preferably 700 parts by mass, per 100 parts by mass in total of components (D), (E), (F) and (G). The range is as follows.

The method of preparing the resin composition that forms the resin layer is not particularly limited, but it is also possible to simply mix the components uniformly. For mixing each component, for example, an extruder, kneader, roll, or the like is used in the absence of a solvent, and a reactor equipped with a stirrer is used in the presence of a solvent.

Next, a method of obtaining a resin-coated copper foil of the present invention by providing a resin layer made of a resin composition on the roughened surface of a copper foil having a surface roughness (Rz) of 1.1 μm or less or on the surface of a non-roughened copper foil. explain.
The resin-coated copper foil of the present invention can be obtained by various known methods. Specifically, a technique of heating the resin composition to lower its viscosity and casting, and a technique of applying a solution and drying the solvent can be used.
A coating means is not particularly limited, and includes a curtain coater, a roll coater, a laminator and the like. In addition, various leveling means may be used in combination. As the copper foil, any known copper foil having a surface roughness (Rz) of 1.1 μm or less with a roughened surface or a non-roughened copper foil is particularly limited. can be used without Specific examples include rolled copper foil and electrolytic copper foil. Its thickness is not particularly limited, and it may be one subjected to surface treatment (roughening, rust prevention).

The resin layer made of the resin composition may be uncured or may be partially cured under heating. The partially cured resin layer is in a so-called B-stage state. Although the thickness of the resin layer is not limited, it is preferably about 12 to 105 μm.

The copper-clad laminate of the present invention can be obtained by heating the resin layer made of the resin composition provided on the surface of the copper foil to form a cured product (resin layer).
The curing temperature and curing time of the resin layer composed of the resin composition may be selected in consideration of the combination of the functional group of the component (D1) or the component (D2) and the reactive group of the thermosetting resin. For example, when the resin composition contains a maleimide resin or an epoxy resin, the curing temperature is preferably 120 to 250° C., and the curing time is approximately several tens of minutes to several hours.

A substrate having the copper-clad laminate of the present invention can also be obtained by laminating a polyimide film or LCP (liquid crystal polymer) on the surface of a resin layer made of a resin composition, heat-pressing, and heat-curing. can. Examples of the base material provided with a copper-clad laminate include copper-clad laminates (CCL), printed wiring boards and multilayer wiring boards having a circuit pattern on the copper foil of CCL.

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. "Parts" in the examples means parts by mass, and "%" means % by mass. The GPC measurement conditions in the examples are as follows.
Model: TOSOH ECOSEC Elite HLC-8420GPC
Column: TSKgel Super AWM-H
Eluent: NMP (N-methylpyrrolidone); 0.5 ml/min, 40°C
Detector: UV (differential refractometer)
Molecular weight standard: Polystyrene

Synthesis Example 1 (Synthesis of isocyanate-modified polyimide resin (D1))
A 300 ml reactor equipped with a thermometer, a reflux condenser, a Dean-Stark device, a raw material inlet, a nitrogen introduction device and a stirring device was charged with BAFL (9,9-bis (4-aminophenyl) fluorene, manufactured by JFE Chemical Co., Ltd. , molecular weight 348.45 g / mol) 6.01 parts, PRIAMINE 1075 (C36 dimer diamine, Croda Japan Co., Ltd., molecular weight 534.38 g / mol) 9.05 parts, ODPA (oxydiphthalic anhydride, Manac Co., Ltd., molecular weight 310.22 g/mol), 58.15 parts of anisole, 0.72 parts of triethylamine and 14.25 parts of toluene were added and heated to 120° C. to dissolve the raw materials. The reaction was carried out at 135° C. for 4 hours while removing water produced by the ring closure of the amic acid by azeotropic distillation with toluene. After the generation of water stopped, residual triethylamine and toluene were removed at 140° C. to obtain a polyamic acid resin imide (C) solution. The molar ratio of the diamine component ((A) component) and the acid anhydride component ((B) component) used in the synthesis of the imidized product (C) (moles of acid anhydride component/moles of diamine component) is 1. 0.05.
Next, 0.22 parts of IPDI (isophorone diisocyanate, manufactured by Degusahüls, molecular weight 222.29 g/mol) and 3.49 parts of anisole are added to the imidized product (C) solution obtained above and heated at 130° C. for 3 hours. Thus, an isocyanate-modified polyimide resin solution (A-1) (30.0% non-volatile content) was obtained. The molar ratio of the raw material components of the isocyanate-modified polyimide resin (the number of moles of the acid anhydride component)/(the number of moles of the diamine component + the number of moles of the diisocyanate component) calculated from the raw materials used in the synthesis was 1.02. (weight average molecular weight is 72,000)

Synthesis Example 2 (Synthesis of isocyanate-modified polyimide resin (D1))
BAPP(2,2-bis[4-(4-aminophenoxy)phenyl]propane, Wakayama Seika Kogyo Co., Ltd., molecular weight 410.52 g / mol) 7.74 parts, PRIAMINE 1075 (C36 dimer diamine, Croda Japan Co., Ltd., molecular weight 534.38 g / mol) 8.17 parts, PMDA (dipyromellitic acid Anhydride, manufactured by Mitsubishi Gas Chemical Co., Ltd., molecular weight 218.12 g / mol) 7.79 parts, 52.7 parts of anisole, 0.72 parts of triethylamine and 13.86 parts of toluene are added and heated to 120 ° C. to obtain raw materials. Dissolved. The reaction was carried out at 135° C. for 4 hours while removing water produced by ring closure of the amic acid by azeotropic distillation with toluene. After the generation of water stopped, residual triethylamine and toluene were removed at 140° C. to obtain a polyamic acid resin imide (C) solution. The molar ratio of the diamine component ((A) component) and the acid anhydride component ((B) component) used in the synthesis of the imidized product (C) (moles of acid anhydride component/moles of diamine component) is 1. 0.05.
Next, 0.22 parts of HDI (hexamethylene diisocyanate, manufactured by Asahi Kasei Corporation, molecular weight 168.20 g/mol) and 2.64 parts of anisole were added to the imidized product (C) solution obtained above, and the mixture was heated at 130°C for 3 hours. An isocyanate-modified polyimide resin solution (A-2) (30.1% non-volatile content) was obtained by heating for a period of time. The molar ratio of the raw material components of the isocyanate-modified polyimide resin (the number of moles of the acid anhydride component)/(the number of moles of the diamine component + the number of moles of the diisocyanate component) calculated from the raw materials used in the synthesis was 1.02. (weight average molecular weight is 73,000)

Synthesis Example 3 (Synthesis of terminal-modified polyimide resin (D2))
Karenz MOI (2-isocyanatoethyl methacrylate, molecular weight 155.15 g / mol) 0.11 parts was added to the isocyanate-modified polyimide resin (D1) obtained by the method of Synthesis Example 1 and heated at 130 ° C. for 4 hours. A modified polyimide resin (A-3) (nonvolatile content: 30.0%) was obtained. (weight average molecular weight is 72,000)

Synthesis Example 4 (Synthesis of polyimide resin for comparison)
A 300 ml reactor equipped with a thermometer, a reflux condenser, a Dean-Stark device, a raw material inlet, a nitrogen introduction device and a stirring device was charged with BAFL (9,9-bis (4-aminophenyl) fluorene, manufactured by JFE Chemical Co., Ltd. , molecular weight 348.45 g / mol) 6.45 parts, PRIAMINE 1075 (C36 dimer diamine, Croda Japan Co., Ltd., molecular weight 534.38 g / mol) 11.71 parts, ODPA (oxydiphthalic anhydride, Manac Co., Ltd., molecular weight 310.22 g/mol), 68.34 parts of anisole, 0.81 parts of triethylamine and 18.99 parts of toluene were added and heated to 120° C. to dissolve the raw materials. The reaction was carried out at 135° C. for 4 hours while removing water produced by ring closure of the amic acid by azeotropic distillation with toluene. After the generation of water stopped, residual triethylamine and toluene were continuously removed at 140° C. to obtain a polyimide resin solution (R-2) (30.2% non-volatile content) for comparison. The molar ratio of the raw material components of the comparative polyimide resin (the number of moles of the acid anhydride component/the number of moles of the diamine component) calculated from the raw materials used in the synthesis was 1.02. (weight average molecular weight is 43,000)

Synthesis Example 5 (Synthesis of polyimide resin for comparison)
BAPP(2,2-bis[4-(4-aminophenoxy)phenyl]propane, Wakayama Seika Kogyo Co., Ltd., molecular weight 410.52 g / mol) 7.53 parts, PRIAMINE 1075 (C36 dimer diamine, Croda Japan Co., Ltd., molecular weight 534.38 g / mol) 12.43 parts, ODPA (oxydiphthalic anhydride , manufactured by Manac Co., Ltd., molecular weight 310.22 g/mol), 72.37 parts of anisole, 0.81 part of triethylamine and 19.51 parts of toluene were added and heated to 120°C to dissolve the raw materials. The reaction was carried out at 135° C. for 4 hours while removing water produced by ring closure of the amic acid by azeotropic distillation with toluene. After the generation of water stopped, residual triethylamine and toluene were continuously removed at 140° C. to obtain a polyimide resin solution (R-1) (30.0% non-volatile content) for comparison. The molar ratio of the raw material components of the comparative polyimide resin (the number of moles of the acid anhydride component/the number of moles of the diamine component) calculated from the raw materials used in the synthesis was 1.05. (weight average molecular weight is 43,000)

Adjustment of the resin composition to be the resin layer of the resin-coated copper foil (Formulation Examples 1 to 19 are resin compositions for resin-coated copper foils of the present invention, Formulation Examples 20 to 27 are resins for resin-coated copper foils of comparative examples Composition)
After blending each component in the amount shown in Tables 1 to 3 (unit is "part", the number of parts of polyimide resin and maleimide resin is the number of parts in terms of solid content not containing solvent), the solid content concentration is By adding 20% by mass of anisole as a solvent and uniformly mixing, resin compositions for resin-coated copper foils of the present invention and comparative examples were prepared.

Each component in Tables 1 to 3 is as follows. Incidentally, the specific surface area of the inorganic filler is a value measured by the BET method.
<Polyimide resin>
(A-1) to (A-3); isocyanate-modified polyimide resins and terminal-modified polyimide resins obtained in Synthesis Examples 1 to 3 Comparative polyimide resins 1 and 2; Comparative polyimide resins obtained in Synthesis Examples 4 and 5 Polyimide resin <thermosetting resin>
MIR-3000-70MT; Maleimide resin, Nippon Kayaku Co., Ltd. XD-1000; Epoxy resin, Nippon Kayaku Co., Ltd. ZXR-1889H; Epoxy acrylate resin, Nippon Kayaku Co., Ltd. <Inorganic filler>
(C-1); SFP-30M (manufactured by Denka Co., Ltd., fused silica, average particle size 0.6 μm, specific surface area 6.2 m ² /g)
(C-2); SFP-20M (manufactured by Denka Co., Ltd., fused silica, average particle size 0.4 μm, specific surface area 11.2 m ² /g)
(C-3); FB-3SDC (manufactured by Denka Co., Ltd., fused silica, average particle size 3.1 μm, specific surface area 3.6 m ² /g)
(C-4); Sciqas 0.7 μm (manufactured by Sakai Chemical Industry Co., Ltd., fused silica, average particle size 0.7 μm, specific surface area 4.3 m ² /g)
(C-5) BA-1 (manufactured by Nikki Shokubai Kasei Co., Ltd., hollow silica, average particle diameter 16 μm, specific surface area 2.0 m ² /g)
(C-6); Sciqas 0.7 μm (manufactured by Sakai Chemical Industry Co., Ltd., surface epoxysilane-treated fused silica, average particle size 0.7 μm, specific surface area 4.3 m ² /g)
(C-7); Sciqas 0.7 μm (manufactured by Sakai Chemical Industry Co., Ltd., surface polysiloxane-treated fused silica, average particle size 0.7 μm, specific surface area 4.3 m ² /g)
(C-8); 10SX-CH1 (manufactured by Admatechs Co., Ltd., surface aminosilane-treated fused silica, average particle size after cutting 5 μm coarse particles: 1.1 μm, specific surface area: 15 m ² /g)
(C-9); Sciqas 0.1 μm (manufactured by Sakai Chemical Industry Co., Ltd., fused silica, average particle size 0.1 μm, specific surface area 21.5 m ² /g)
(C-10); Nanoace D600 (manufactured by Nippon Talc Co., Ltd., talc, average particle size 0.6 μm, specific surface area 24 m ² /g)
(C-11); DAW-03 (manufactured by Denka Co., Ltd., alumina, average particle size 4.9 μm, specific surface area 0.5 m ² /g)
<Curing agent>
DCP; dicumyl peroxide, manufactured by Kayaku Nourion Co., Ltd. <Additive>
KR-513; Silane coupling agent, Shin-Etsu Chemical Co., Ltd. TT-LX; Lubricating oil additive, Johoku Chemical Co., Ltd. KTL-8FH; Teflon (registered trademark) powder, average particle size 3.5 μm, Co., Ltd. Made by Kitamura

Examples 1 to 19 and Comparative Examples 1 to 8 (Preparation of resin-coated copper foils of the present invention and comparative examples)
Fukuda Metal Foil & Powder Co., Ltd. ultra-low roughness non-roughening treated electrolytic copper foil CF-T9DA-SV (hereinafter referred to as “T9DA”. Copper foil thickness 12 μm, surface roughness 0.85 μm.) Using an automatic applicator, each of the resin compositions of Formulation Examples 1 to 19 was applied to the rough surface of , in such an amount that the film thickness of the resin layer after coating and drying was 30 μm, and dried by heating at 120 ° C. for 10 minutes. The resin-coated copper foils of Examples 1 to 19 were prepared. Also, using the resin compositions of Formulation Examples 20 to 27, resin-coated copper foils of Comparative Examples 1 to 8 were produced in the same manner as described above.

(Evaluation of variation in film thickness of resin layer possessed by resin-coated copper foil)
For the resin-coated copper foils obtained in Examples 1 to 19 and Comparative Examples 1 to 8, the thickness of the copper foil was subtracted from the thickness measured at 10 arbitrarily selected locations, and the thickness of the resin layer was obtained at 10 locations. I asked for the thickness. Among the 10 film thicknesses obtained above, the difference between the maximum film thickness and the minimum film thickness was calculated, and the variation in film thickness was evaluated according to the following evaluation criteria. The results are shown in Tables 1-3.
○: The difference between the maximum film thickness and the minimum film thickness is less than 4.0 μm ×: The difference between the maximum film thickness and the minimum film thickness is 4.0 μm or more

Examples 20 to 38 and Comparative Examples 9 to 16 (Preparation of copper-clad laminates of the present invention and comparative examples)
PPE prepreg (Meteorwave 4000, manufactured by AGC nelco Co., Ltd.) was superimposed on the resin layer of the resin-coated copper foil obtained in Examples 1 to 19 and Comparative Examples 1 to 8, and vacuum was applied at 200 ° C. for 60 minutes at 3 MPa. By pressing to cure the resin layer, copper-clad laminates of Examples 20 to 38 and Comparative Examples 9 to 16 were produced.

(Evaluation of adhesive strength of copper-clad laminate)
Each copper-clad laminate obtained in Examples 20 to 38 and Comparative Examples 9 to 16 was cut into 10 mm widths, and PPE prepregs and resin compositions were prepared using Autograph AGS-X-500N (manufactured by Shimadzu Corporation). 90° peeling strength (peeling speed: 50 mm/min) from a copper foil having a resin layer composed of a cured product of (1) was measured, and the adhesive strength was evaluated according to the following evaluation criteria. Incidentally, when the samples after the test were visually checked, cohesive failure had occurred in all of them. The results are shown in Tables 1-3.
◎: 6.5 N/cm or more ○: 5.5 N/cm or more and less than 6.5 N/cm △: 4.5 N/cm or more and less than 5.5 N/cm ×: 4.5 N/cm less than cm

(Evaluation of thermal properties of copper clad laminate)
The resin-coated copper foils obtained in Examples 1 to 19 and Comparative Examples 1 to 8 were floated in a solder bath heated to 288 ° C. with POT-200C (manufactured by Taiyo Denki Sangyo Co., Ltd.) until blisters appeared. The time was measured and the thermal properties were evaluated according to the following evaluation criteria. The results are shown in Tables 1-3.
◎: No swelling for 10 minutes or more ○: Blistering occurred for 1 minute or more and less than 10 minutes ×: Blistering occurred for less than 1 minute

(Evaluation of Dielectric Constant and Dielectric Loss Tangent of Resin Layer Consisting of Cured Resin Composition)
Resins were prepared in the same manner as in Examples 1 to 19 and Comparative Examples 1 to 8, except that the coating amount of the resin composition of Formulation Examples 1 to 27 was changed from an amount that resulted in a film thickness of the resin layer of 30 µm to an amount that resulted in a film thickness of 100 µm. After the coated copper foil was produced, the resin layer was cured by heating at 200° C. for 60 minutes to obtain a copper-clad laminate. The copper foil of the copper clad laminate obtained above is removed by etching with an iron (III) chloride solution having a liquid specific gravity of 45 Baume degrees, washed with ion-exchanged water, and dried at 105 ° C. for 10 minutes to obtain a resin. A resin layer composed of a cured product of the composition was obtained. For the resin layer obtained above, the stress at break, elongation at break, and elastic modulus were measured using Autograph AGS-X-500N (manufactured by Shimadzu Corporation), and using a network analyzer 8719ET (manufactured by Agilent Technologies). The dielectric constant and dielectric loss tangent at 10 GHz were measured by the cavity resonance method. The results are shown in Tables 1-3.

From the results in Tables 1 to 3, the resin-coated copper foil of the present invention has little variation in film thickness, and the copper-clad laminate obtained by curing the resin layer composed of the resin composition of the resin-coated copper foil has an adhesive strength. and high heat resistance, and it is clear that the cured product of the resin layer made of the resin composition is excellent in dielectric properties.

Since the resin composition that forms the resin layer of the resin-coated copper foil of the present invention has excellent coatability, the resin-coated copper foil can be prepared by a simple method. In addition, the copper-clad laminate obtained by curing the resin layer composed of the resin composition of the resin-coated copper foil of the present invention has excellent adhesion between the cured resin layer and the copper foil, and the cured resin layer has excellent adhesion. Since it has good heat resistance and excellent dielectric properties, it can be suitably used for printed wiring boards and the like.

Claims (8)

A resin-coated copper foil having a resin layer made of a resin composition on the roughened surface of the copper foil or the surface of the non-roughened copper foil having a surface roughness (Rz) of 1.1 μm or less, wherein the resin composition is An imide of a polyamic acid resin which is a copolymer of an amino compound (A) containing an aliphatic diamino compound (a1) having 6 to 36 carbon atoms and an aromatic diamino compound (a2) and a tetrabasic dianhydride (B) An isocyanate-modified polyimide resin (D1) that is a reaction product of a terminal functional group and a diisocyanate possessed by the compound (C) or an isocyanate-modified terminal-modified polyimide resin (D2) that is a terminal-modified product of the isocyanate-modified polyimide resin, the ratio in the BET method A resin-coated copper foil containing silica (E) having a surface area of 1.0 to 20 m ² /g, a thermosetting resin (F) and a curing agent (G). 2. The resin-coated copper foil according to claim 1, wherein the content of silica (E) is 5 to 50% by mass based on the solid content of the isocyanate-modified polyimide resin (D1) or the isocyanate-modified terminal-modified polyimide resin (D2). 3. The resin-coated copper foil according to claim 1, wherein silica (E) has an average particle size of 0.3 to 5.0 [mu]m. The resin-coated copper foil according to any one of claims 1 to 4, wherein the silica (E) is silica that has not been surface-treated with a silane compound. Tetrabasic dianhydride (B) is represented by the following formulas (1) to (5)

(In formula (4), Y is C(CF ₃ ) ₂ , SO ₂ , CO, an oxygen atom, a direct bond, or the following formula (6)

Represents a divalent linking group represented by )
The resin-coated copper foil according to claim 1, comprising a compound selected from the group consisting of The aromatic diamino compound (a2) is represented by the following formulas (7) to (10)

(In formula (9), R ₂ independently represents a methyl group or a trifluoromethyl group; in formula (10), Z is CH(CH ₃ ), SO ₂ , CH ₂ , O—C ₆ H ₄ — O, an oxygen atom, a direct bond, or the following formula (6)

_R3 independently represents a hydrogen atom, a methyl group, an ethyl group or a trifluoromethyl group. 2. The resin-coated copper foil according to claim 1, comprising a compound selected from the group consisting of ). The resin-coated copper foil according to claim 1, wherein the thermosetting resin (F) contains an aromatic maleimide resin. A copper-clad laminate obtained by curing a resin layer composed of a resin composition contained in the resin-coated copper foil according to any one of claims 1 to 7.