JP2018014388A - Thermosetting resin composition, resin film for interlayer insulation, printed wiring board and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite film for an electronic device using high-frequency band signals, which is low in dielectric dissipation factor, superior in surface smoothness, and high in the adhesion with plated copper; a printed wiring board including a cured product of the composite film for an electronic device; and a method for manufacturing the printed wiring board.SOLUTION: A composite film for an electronic device using high-frequency band signals, a printed wiring board including a cured product of the composite film for an electronic device, and a method for manufacturing the printed wiring board are disclosed. The composite film comprises an A layer and a B layer, in which the thickness of the B layer is 1-5 μm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermosetting resin composition, a resin film for interlayer insulation, a printed wiring board, and a method for producing the same.

  In recent years, electronic devices have been further reduced in size, weight, and functionality, and along with this, LSI (Large Scale Integration), chip parts, etc. have been highly integrated, and their forms are also multi-pin and miniaturized. It is changing rapidly. For this reason, in order to improve the mounting density of electronic components, development of micro wiring of a multilayer printed wiring board has been advanced. As a multilayer printed wiring board meeting these requirements, a multilayer printed wiring board having a build-up structure in which an insulating resin film not containing glass cloth is used as an insulating layer (hereinafter also referred to as “build-up layer”) instead of a prepreg. However, it is becoming mainstream as a printed wiring board suitable for weight reduction, miniaturization and miniaturization.

  The build-up layer is required to have a low thermal expansion in order to improve the processing dimension stability and reduce the amount of warpage after semiconductor mounting. One method for reducing the thermal expansion of the build-up layer is a method of highly filling an inorganic filler. For example, low thermal expansion of the buildup layer is achieved by using 40% by mass or more of the buildup layer as a silica filler (Patent Documents 1 to 3).

On the other hand, in recent years, computers and information communication devices have become more and more sophisticated and highly functional, and in order to process a large amount of data at high speed, signals to be handled tend to become higher in frequency. In particular, the frequency range of radio waves used in mobile phones and satellite broadcasts is in the high frequency range of the GHz band. In order to suppress transmission loss due to higher frequencies, organic materials used in the high frequency range include dielectrics. Materials with low rates and dielectric loss tangents are desired.
Various efforts have been made for this. For example, Patent Document 4 discloses a resin composition containing a cyanate resin.

JP 2007-87982 A JP 2009-280758 A JP 2005-39247 A Japanese Patent Application Laid-Open No. 2014-136791

  In order to apply a multilayer printed wiring board having a build-up structure, there is an increasing demand for a film having a higher frequency characteristic than that of the prior art. In addition, as a multilayer printed wiring board having a build-up structure, it is required to have term adhesiveness with plated copper.

  The present invention has been made in view of such a situation, and has a low dielectric loss tangent, excellent surface smoothness, and high adhesiveness with plated copper, and a composite film for electronic equipment using a signal in a high frequency band. It is an object to provide a printed wiring board containing a cured product of the composite film for electronic devices, and a method for manufacturing the printed wiring board.

As a result of studying to solve the above problems, the present inventors have found that a specific composite film can solve the above problems. That is, the present invention provides the following [1] to [6].
[1] A composite film for an electronic device comprising a layer A and a layer B and using a signal in a high frequency band in which the thickness of the layer B is 1 to 5 μm.
[2] A composite film for electronic equipment using a signal in a high frequency band according to [1], wherein the thickness of the A layer is 10 to 40 μm.
[3] A composite film for electronic equipment, which includes a layer A and a layer B, and uses a signal in a high frequency band in which the weight loss after desmearing of the layer B is 1 g / m 2 or less.
[4] The minimum melt viscosity at 80 to 150 ° C. of the A layer is 100 to 5,000 Pa · s, and the minimum melt viscosity at 80 to 150 ° C. of the B layer is 50,000 Pa · s or more. The composite film for electronic devices which uses the signal of the high frequency band in any one of-[3].
[5] The high frequency band signal according to any one of [1] to [4], wherein the A layer contains a polyimide compound having a structural unit derived from a maleimide compound and a structural unit derived from a diamine compound and an inorganic filler. Composite film for electronic equipment to be used.
[6] The composite film for electronic devices using the signal in the high frequency band according to any one of [1] to [5], wherein the B layer contains a polyfunctional epoxy resin and a phenolic hydroxyl group-containing polyamide resin.
[7] A composite film for electronic equipment using a signal in a high frequency band according to any one of [1] to [6], wherein a dielectric loss tangent at 5 GHz is 0.005 or less.
[8] A printed wiring board having a cured product of a composite film for electronic equipment using a signal in a high-frequency band, including an A layer and a B layer, and a circuit embedded in the A layer, the thickness of the A layer Is a (μm), the thickness of the B layer is b (μm), and the height of the circuit is c (μm), a printed wiring board in which c ≦ a ≦ 3c and 1 ≦ b ≦ 10.
[9] Manufacture of a printed wiring board comprising a step of laminating a composite film for electronic equipment using a signal in a high frequency band according to any one of [1] to [7] on one side or both sides of a circuit board Method.

  According to the present invention, there is provided a composite film for electronic equipment using a signal in a high frequency band, having a low dielectric loss tangent, excellent surface smoothness, and high adhesion to plated copper, and the electronic equipment It is possible to provide a printed wiring board containing a cured product of a composite film for use, and a method for producing a printed wiring board.

It is a schematic cross section showing the composite film of this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail. In this specification, a numerical range that is greater than or equal to X and less than or equal to Y (X and Y are real numbers) may be expressed as “X to Y”. For example, the description “0.1-2” indicates a numerical range that is 0.1 or more and 2 or less, and the numerical range includes 0.1, 0.34, 1.03, 2, and the like.

In the present specification, the “composite film” includes both a composite film in which the resin composition contained is uncured and a composite film obtained by semi-curing the resin composition contained in a so-called B-stage form.
In this specification, “composite” of a composite film means that the film is formed of a plurality of resin layers, and if the mode is included, the composite film further includes a support and a protective film. You may have another layer.

  Further, in this specification, the “interlayer insulating layer” is a layer that is located between two conductor layers and insulates the conductor layer. Examples of the “interlayer insulating layer” in the present specification include a cured product of a composite film. Note that in this specification, the “layer” includes a part in which a part is missing and a part in which a via or a pattern is formed.

[Composite film for electronic equipment using high-frequency band signals]
The composite film for electronic devices according to the present invention includes at least an A layer and a B layer.

The composite film of the present invention has the A layer and the B layer, and a support may be provided on the surface of the B layer opposite to the A layer. In this case, the configuration is A layer / B layer / support. Examples of the support include polyolefin films such as polyethylene, polypropylene and polyvinyl chloride; polyester films such as polyethylene terephthalate (hereinafter also referred to as “PET”) and polyethylene naphthalate; various plastics such as polycarbonate films and polyimide films. A film etc. are mentioned. Moreover, you may use metal foil, release paper, etc., such as copper foil and aluminum foil. The support and the protective film described later may be subjected to surface treatment such as mat treatment or corona treatment. The support may be subjected to a release treatment with a silicone resin release agent, an alkyd resin release agent, a fluororesin release agent, or the like.
Although the thickness of a support body is not specifically limited, 10-150 micrometers is preferable and 25-50 micrometers is more preferable.

The composite film of the present invention may be provided with a protective film. For example, the aspect which provides a protective film in the surface on the opposite side to B layer in A layer is mentioned. In this case, for example, the protective film / A layer / B layer, protective film / A layer / B layer / support, and the like are configured.
Examples of the protective film include a plastic film such as a polytetrafluoroethylene film, a polyethylene terephthalate film, a polyethylene film, a polypropylene film, a polymethylpentene film, and a polyimide film. In addition, the protective film may be subjected to surface treatment such as primer coating, UV treatment, corona discharge treatment, polishing treatment, etching treatment, mold release treatment, and the like as necessary.
The support may be used as a protective film.

The composite film of the present invention is produced, for example, by a method in which a B layer is formed on the support, an A layer is formed on the B layer, and a protective layer is formed on the A layer as necessary. can do. For the formation of the B layer, a B layer varnish, which will be described later, is applied to the support, and then dried by heating. Further, the A layer varnish, which will be described later, is applied thereon, and then heated and dried. Can do. As a method for coating the varnish, for example, a coating apparatus such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, or a die coater can be used. These coating apparatuses are preferably selected as appropriate depending on the film thickness.
The drying conditions after coating are not particularly limited, and may be appropriately determined according to the type of solvent. For example, when forming the A layer, the drying temperature is preferably 50 to 130 ° C, more preferably 70 to 110 ° C. When the A layer is formed, the drying time can be, for example, 1 to 10 minutes. For example, when the B layer is formed, the drying temperature is preferably 50 to 150 ° C, more preferably 100 to 145 ° C. When the B layer is formed, the drying time can be, for example, 1 to 10 minutes.
In the said drying, it is preferable to dry so that content of the volatile component (mainly organic solvent) in the A layer or B layer after drying may be 10 mass% or less, and it may become 6 mass% or less. More preferably, it is dried.

  In addition, the composite film of the present invention can also be produced by preparing an A-layer film and a B-layer film and bonding them together using a thermocompression bonding or laminator at a softening temperature or higher.

  In the composite film of the present invention, the thickness of the A layer is preferably 10 to 40 μm in order to embed the uneven height of the circuit. The thickness of the A layer is more preferably 15 to 35 μm, and further preferably 20 to 35 μm.

  On the other hand, the B layer is a layer that can be applied to the semi-additive method. In order to ensure surface flatness and ensure high adhesiveness with plated copper, the thickness of the B layer is preferably 1 to 5 μm, more preferably 1 to 3 μm, and more preferably 1.5 to 3 μm. More preferably. If the thickness of the B layer is 1 μm or more, it is easy to avoid the B layer from breaking and being exposed on the surface when embedding in the unevenness of the circuit, and the B layer is eluted and disappears by the desmear process. There is little possibility of doing. On the other hand, if it is 5 micrometers or less, while being easy to suppress the fall of surface flatness and being able to make a board | substrate thin, it is preferable.

  When the thickness of the A layer is a (μm), the thickness of the B layer is b (μm), and the height of the circuit is c (μm), the relationship of c ≦ a ≦ 2c and 1 ≦ b ≦ 5 is satisfied. It is preferable to use a composite film. A film satisfying this relationship can achieve both sufficient embedding and fine circuit formability.

  The weight loss after desmearing of the B layer is preferably 1 g / m 2 or less. The weight reduction after desmearing can be measured by, for example, roughening by the method described in the Examples and comparing the weight before and after the roughening. The weight loss after desmearing is preferably 0.8 g / m 2 or less, and more preferably 0.7 g / m 2 or less.

The A layer preferably has a minimum melt viscosity at 80 to 150 ° C. of 100 to 4,000 Pa · s. If it is this range, A layer can be made to flow at 80-150 degreeC, and it is preferable from a viewpoint of an embedding property. The minimum melt viscosity at 80 to 150 ° C. of the A layer is more preferably 500 to 2,000 Pa · s, and further preferably 700 to 2,000 Pa · s. Here, the minimum melt viscosity is the viscosity when the resin composition is melted before the start of curing.
When the minimum melt viscosity at 80 to 150 ° C. is 100 Pa · s or more, the fluidity of the film does not increase excessively, it becomes easy to maintain the surface flatness of the composite film after embedding, and the thickness of the substrate varies. Can be suppressed. Moreover, when it is 4,000 Pa · s or less, the fluidity is improved and the unevenness of the wiring is easily embedded.

  On the other hand, the B layer preferably has a minimum melt viscosity at 80 to 150 ° C. of 50,000 Pa · s or more. The B layer maintains a constant thickness when the composite film is embedded in a circuit, and it is easy to maintain the surface flatness of the composite film after embedding. From the same viewpoint, the minimum melt viscosity of the B layer at 80 to 150 ° C. is preferably 50,000 to 100,000 Pa · s, more preferably 50,000 to 75,000 Pa · s, 60 It is more preferable that it is 5,000-75,000 Pa.s, and it is especially preferable that it is 63,000-70,000 Pa.s.

  The composite film of the present invention can be cured by heat or active energy rays. Examples of the active energy rays include electromagnetic waves such as ultraviolet rays, visible rays, infrared rays, and X-rays; and particle rays such as α rays, γ rays, and electron beams. Among these, ultraviolet rays are preferable.

An example of the composite film of the present invention is shown in FIG. 1 as a schematic cross-sectional view. The composite film according to the present invention includes a first resin layer 1 and a second resin layer 2, and a support 3 and / or a protective film 4 as necessary.
Note that there is no clear interface between the first resin layer 1 and the second resin layer 2, for example, part of the constituent components of the first resin layer 1 and the second resin layer A part of the two constituent components may be in a compatible and / or mixed state.

  In the composite film of the present invention, the components of each layer are not particularly limited as long as the above conditions are satisfied, but the components of the A layer and the B layer will be described below as an example of the embodiment.

[Components of layer A]
A resin composition is mentioned as a component of A layer. As the resin composition, for example, a resin composition containing a polyimide compound (a1) having a structural unit derived from a maleimide compound and a structural unit derived from a diamine compound and an inorganic filler (a2) is preferable. More preferably, the content of the filler (a2) is 55% by volume or more based on the solid content of the resin composition. Hereinafter, each component will be described in detail.

<Polyimide compound (a1)>
The polyimide compound (a1) has a structural unit derived from a maleimide compound and a structural unit derived from a diamine compound. The maleimide compound preferably includes an aliphatic maleimide compound.
The aliphatic maleimide compound preferably has 6 to 40 carbon atoms between imide groups, and preferably has at least two N-substituted maleimide groups. By using the polyimide compound (a1) having a structural unit derived from an aliphatic maleimide compound, the dielectric loss tangent is low, and the handling property when formed into a film tends to be excellent.
Examples of the aliphatic maleimide compound include 1,6-bismaleimide- (2,2,4-trimethyl) hexane, pyrroluronic acid binder type long-chain alkyl bismaleimide, and the like. These may be used individually by 1 type and may use 2 or more types together. The aliphatic maleimide is more preferably 1,6-bismaleimide- (2,2,4-trimethyl) hexane from the viewpoint that the coefficient of thermal expansion is low and the glass transition temperature is high.

  Further, the maleimide compound may include a maleimide compound other than the aliphatic maleimide compound, and the maleimide compound is not particularly limited as long as it is a maleimide compound having two or more N-substituted maleimide groups. For example, bis (4-maleimidophenyl) methane, polyphenylmethanemaleimide, bis (4-maleimidophenyl) ether, bis (4-maleimidophenyl) sulfone, 3,3′-dimethyl-5,5′-diethyl-4, Examples include 4′-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, m-phenylene bismaleimide, 2,2-bis [4- (4-maleimidophenoxy) phenyl] propane, and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, 2,2-bis [4- (4-maleimidophenoxy) phenyl] propane is preferable from the viewpoints of adhesion to a conductor and mechanical properties.

The content of the structural unit derived from the aliphatic maleimide compound in the polyimide compound (a1) is preferably 5% by mass or more, and more preferably 10% by mass or more in terms of charge. The upper limit is not particularly limited and may be 100% by mass, but is preferably 80% by mass or less, more preferably 60% by mass or less, still more preferably 40% by mass or less, and particularly preferably 30% by mass or less. When the content of the structural unit derived from the aliphatic maleimide compound is within the above range, the resin composition tends to obtain better high-frequency characteristics and film handling properties.
Moreover, 5-50 mass% is preferable in conversion of preparation amount, and, as for content of the structural unit derived from an aliphatic maleimide compound with respect to the total content of the structural unit derived from a maleimide compound, 10-40 mass% is more preferable.

  Examples of the structural unit derived from the maleimide compound include a group represented by the following general formula (1-1), a group represented by the following general formula (1-2), and the like.

In general formulas (1-1) and (1-2), A ¹ represents a residue of a maleimide compound, and * represents a bonding part.
In addition, a residue means the structure of the part remove | excluding the functional group (in the maleimide compound, maleimide group) used for the coupling | bonding from the raw material component.

The residue represented by A ¹ is preferably a divalent group represented by the following general formula (2), (3), (4) or (5).

（式中、Ｒ^１は各々独立に、水素原子、炭素数１〜５の脂肪族炭化水素基、又はハロゲン原子を示す。）

(In the formula, each R ¹ independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms, or a halogen atom.)

（式中、Ｒ^２及びＲ^３は各々独立に、水素原子、炭素数１〜５の脂肪族炭化水素基又はハロゲン原子を示し、Ａ^２は炭素数１〜５のアルキレン基若しくはアルキリデン基、エーテル基、スルフィド基、スルフォニル基、カルボオキシ基、ケトン基、単結合又は下記一般式（３−１）で表される基である。）

(In the formula, R ² and R ³ each independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom, and A ² represents an alkylene group or alkylidene group having 1 to 5 carbon atoms, ether) A group, a sulfide group, a sulfonyl group, a carbooxy group, a ketone group, a single bond, or a group represented by the following general formula (3-1).)

（式中、Ｒ^４及びＲ^５は各々独立に、水素原子、炭素数１〜５の脂肪族炭化水素基又はハロゲン原子を示し、Ａ^３は炭素数１〜５のアルキレン基、イソプロピリデン基、エーテル基、スルフィド基、スルフォニル基、カルボオキシ基、ケトン基又は単結合である。）

(Wherein R ⁴ and R ⁵ each independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom, A ³ represents an alkylene group having 1 to 5 carbon atoms, an isopropylidene group, Ether group, sulfide group, sulfonyl group, carbooxy group, ketone group or single bond.)

（式中、ｉは１〜１０の整数である。）

(In the formula, i is an integer of 1 to 10.)

（式中、Ｒ^６及びＲ^７は各々独立に、水素原子又は炭素数１〜５の脂肪族炭化水素基を示し、ｊは１〜８の整数である。）

(In the formula, R ⁶ and R ⁷ each independently represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms, and j is an integer of 1 to 8).

R ¹ in general formula ( ² ), R ² and R ³ in general formula ( ³ ), R ⁴ and R ⁵ in general formula (3-1), R ⁶ and R ^{7 in} general formula (5) As the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-pentyl group, etc. Is mentioned. The aliphatic hydrocarbon group may be an aliphatic hydrocarbon group having 1 to 3 carbon atoms or a methyl group.
The general formula (3) A ² and general formula (3-1) alkylene group of 1 to 5 carbon atoms represented by A ³ in in, methylene group, ethylene group, propylene group, butylene group, pentylene group and the like Can be mentioned.
Examples of the alkylidene group having 1 to 5 carbon atoms represented by A ² in the general formula (3) include an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, and a pentylidene group.

The diamine compound is not particularly limited as long as it is a compound having two amino groups.
Examples of the diamine compound include 4,4′-diaminodiphenylmethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, 4,4′- Diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ketone, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'- Diaminobiphenyl, 2,2′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dihydroxybenzidine, 2,2-bis (3-amino-4-hydroxyphenyl) propane, 3,3′-dimethyl- 5,5′-diethyl-4,4′-diphenylmethanediamine, 2,2-bis (4-aminophenyl) propane, 2,2-bis [4 (4-aminophenoxy) phenyl] propane, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4 , 4′-bis (4-aminophenoxy) biphenyl, 1,3-bis {1- [4- (4-aminophenoxy) phenyl] -1-methylethyl} benzene, 1,4-bis {1- [4 -(4-aminophenoxy) phenyl] -1-methylethyl} benzene, 4,4 '-[1,3-phenylenebis (1-methylethylidene)] bisaniline, 4,4'-[1,4-phenylenebis (1-Methylethylidene)] bisaniline, 3,3 ′-[1,3-phenylenebis (1-methylethylidene)] bisaniline, bis [4- (4-aminophenoxy) pheny ] Sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 9,9-bis (4-aminophenyl) fluorene, and the like. These may be used individually by 1 type and may use 2 or more types together.
Among these, 4,4′-diaminodiphenylmethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4 ′ from the viewpoints of solubility in organic solvents, reactivity during synthesis, and heat resistance -Diamino-3,3'-diethyldiphenylmethane, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 4,4 '-[1,3-phenylenebis (1-methylethylidene)] bisaniline and 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bisaniline is preferred. The diamine compound is preferably 3,3′-dimethyl-5,5′-diethyl-4,4′-diaminodiphenylmethane from the viewpoints of dielectric properties and low water absorption. In addition, 2,2-bis [4- (4-aminophenoxy) phenyl] propane is preferable from the viewpoint of high adhesiveness with a conductor and mechanical properties. Furthermore, from the viewpoints of solubility in organic solvents, reactivity during synthesis, heat resistance, high adhesion to conductors, and excellent high frequency characteristics and low hygroscopicity, 4,4 ′-[1 , 3-phenylenebis (1-methylethylidene)] bisaniline and 4,4 ′-[1,4-phenylenebis (1-methylethylidene)] bisaniline are preferred, and 4,4 ′-[1,3-phenylenebis ( 1-methylethylidene)] bisaniline is more preferred.

  In the polyimide compound (a1), the content of the structural unit derived from the diamine compound is preferably 2 to 30% by mass, more preferably 5 to 20% by mass, and further preferably 5 to 15% by mass in terms of the amount charged. When the content of the structural unit derived from the diamine compound is within the above range, better high-frequency characteristics, heat resistance, flame retardancy, and glass transition temperature tend to be obtained.

  Examples of the structural unit derived from the diamine compound include a group represented by the following general formula (6-1), a group represented by the following general formula (6-2), and the like.

In the general formulas (6-1) and (6-2), A ⁴ represents a residue of the diamine compound, and * represents a bonding part.

The residue A ⁴ is shown, is preferably a divalent group represented by the following general formula (7).

（式中、Ｒ^８及びＲ^９は各々独立に、水素原子、炭素数１〜５の脂肪族炭化水素基、炭素数１〜５のアルコキシ基、水酸基又はハロゲン原子を示し、Ａ^５は炭素数１〜５のアルキレン基若しくはアルキリデン基、エーテル基、スルフィド基、スルフォニル基、カルボオキシ基、ケトン基、フルオレニレン基、単結合、下記一般式（７−１）又は下記一般式（７−２）で表される基である。）

(Wherein R ⁸ and R ⁹ each independently represent a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a hydroxyl group or a halogen atom, and A ⁵ represents the number of carbon atoms. 1-5 alkylene groups or alkylidene groups, ether groups, sulfide groups, sulfonyl groups, carbooxy groups, ketone groups, fluorenylene groups, single bonds, represented by the following general formula (7-1) or the following general formula (7-2) Group.)

（式中、Ｒ^１０及びＲ^１１は各々独立に、水素原子、炭素数１〜５の脂肪族炭化水素基又はハロゲン原子を示し、Ａ^６は炭素数１〜５のアルキレン基、イソプロピリデン基、ｍ−又はｐ−フェニレンジイソプロピリデン基、エーテル基、スルフィド基、スルフォニル基、カルボオキシ基、ケトン基又は単結合である。）

(Wherein R ¹⁰ and R ¹¹ each independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom, A ⁶ represents an alkylene group having 1 to 5 carbon atoms, an isopropylidene group, m- or p-phenylenediisopropylidene group, ether group, sulfide group, sulfonyl group, carbooxy group, ketone group or single bond)

（式中、Ｒ^１２は各々独立に、水素原子、炭素数１〜５の脂肪族炭化水素基又はハロゲン原子を示し、Ａ^７及びＡ^８は炭素数１〜５のアルキレン基、イソプロピリデン基、エーテル基、スルフィド基、スルフォニル基、カルボオキシ基、ケトン基又は単結合である。）

(In the formula, each R ¹² independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom, and A ⁷ and A ⁸ are an alkylene group having 1 to 5 carbon atoms, an isopropylidene group, Ether group, sulfide group, sulfonyl group, carbooxy group, ketone group or single bond.)

^{R 8} and ^{R 9} in the general formula (7), ^{R 10} and ^{R 11} in the general formula (7-1), the formula (7-2) aliphatic C1-5 indicated ^{R 12} in carbonization hydrogen groups is described similarly to the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ¹ in the general formula (2).
As the alkylene group having 1 to 5 carbon atoms represented by A ⁵ in general formula (7), A ⁶ in general formula (7-1), A ⁷ in general formula (7-2) and A ⁸ , This is explained in the same manner as the alkylene group having 1 to 5 carbon atoms represented by A ² in the general formula (3).
The alkylidene group having 1 to 5 carbon atoms represented by A ⁵ in formula (7), is described as with an alkylidene group having 1 to 5 carbon atoms A ² represents in the general formula (3).

  The polyimide compound (a1) contains a polyamino bismaleimide compound represented by the following general formula (8) from the viewpoints of solubility in an organic solvent, high frequency characteristics, high adhesion to a conductor, film formability, and the like. It is preferable.

（式中、Ａ^９は前記一般式（１−１）のＡ^１と同様に説明され、Ａ^１０は前記一般式（６−１）のＡ^４と同様に説明される。）

(In the formula, A ⁹ is explained in the same manner as A ^{1 in the} general formula (1-1), and A ¹⁰ is explained in the same manner as A ^{4 in the} general formula (6-1).)

(Method for producing polyimide compound (a1))
The polyimide compound (a1) can be produced, for example, by reacting a maleimide compound and a diamine compound in an organic solvent.
There is no restriction | limiting in particular in the organic solvent used when manufacturing a polyimide compound (a1), A well-known solvent can be used. Examples of the organic solvent include, but are not limited to, alcohols such as methanol, ethanol, butanol, butyl cellosolve, ethylene glycol monomethyl ether, and propylene glycol monomethyl ether; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; toluene, xylene, Aromatic hydrocarbons such as mesitylene; esters such as methoxyethyl acetate, ethoxyethyl acetate, butoxyethyl acetate and ethyl acetate; amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone System solvents and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, methyl ethyl ketone, cyclohexanone, propylene glycol monomethyl ether, N, N-dimethylformamide, and N, N-dimethylacetamide are preferable from the viewpoint of solubility.

The amount of the maleimide compound and diamine compound used in the production of the polyimide compound (a1) is equivalent to the equivalent ratio of the —NH ₂ group equivalent (Ta2) of the diamine compound to the maleimide group equivalent (Ta1) of the maleimide compound (Ta2 / Ta1). ) Is preferably 0.05 to 10.0, more preferably 0.05 to 1.0, and still more preferably 0.1 to 0.8. By reacting the maleimide compound and the diamine compound within the above range, better high-frequency characteristics, heat resistance, flame retardancy, and glass transition temperature tend to be obtained.

  When manufacturing a polyimide compound (a1) by making a maleimide compound and a diamine compound react, a reaction catalyst can also be used as needed. Although it does not restrict | limit as a reaction catalyst, For example, Acid catalysts, such as p-toluenesulfonic acid; Amines, such as a triethylamine, a pyridine, and a tributylamine; Imidazoles, such as methylimidazole and phenylimidazole; Etc. These may be used individually by 1 type and may use 2 or more types together. Moreover, although the compounding quantity of a reaction catalyst is not specifically limited, For example, it can be used in 0.01-5.0 mass parts with respect to 100 mass parts of total amounts of a maleimide compound and a diamine compound.

A polyimide compound (a1) is obtained by charging a maleimide compound, a diamine compound, an organic solvent and, if necessary, a predetermined amount of a reaction catalyst or the like into a synthesis kettle and causing a Michael addition reaction. The reaction conditions in this step are not particularly limited, but from the viewpoint of workability such as reaction rate and suppression of gelation, for example, the reaction temperature is preferably 50 to 160 ° C., and the reaction time is preferably 1 to 10 hours. .
In this step, the above-mentioned organic solvent may be added or concentrated to adjust the solid content concentration of the reaction raw material and the solution viscosity. Although it does not restrict | limit especially as solid content concentration of a reaction raw material, For example, 10-90 mass% is preferable, and 20-80 mass% is more preferable. When the solid content concentration of the reaction raw material is 10% by mass or more, the reaction rate does not become too slow, which is advantageous in terms of production cost. Further, when the solid content concentration of the reaction raw material is 90% by mass or less, good solubility is obtained, the stirring efficiency is good, and gelation is rare.
In addition, after manufacture of a polyimide compound (a1), it may concentrate by removing a part or all of an organic solvent according to the objective, and may add and dilute an organic solvent. As the organic solvent used additionally, the organic solvent exemplified in the description of the method for producing the polyimide compound (a1) can be applied.

  Although the weight average molecular weight (Mw) of a polyimide compound (a1) is not specifically limited, For example, 800-10,000 are preferable, 800-8,000 are more preferable, 800-5,000 are further more preferable, 1,000 ˜5,000 is particularly preferred, and 1,500 to 4,000 is most preferred. The weight average molecular weight of a polyimide compound (a1) can be calculated | required by the method as described in an Example.

(Content of polyimide compound (a1))
Although content of the polyimide compound (a1) in a resin composition is not specifically limited, 40-95 mass% is preferable with respect to all the resin components contained in a resin composition, 60-95 mass% is more preferable, 65-85 mass% is further more preferable. By setting the content of the polyimide compound (a1) within the above range, insulation reliability is excellent, and a low thermal expansion coefficient, a high glass transition temperature, and a good dielectric loss tangent tend to be obtained.

<Inorganic filler (a2)>
The inorganic filler (a2) is not particularly limited. For example, silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, Examples thereof include aluminum borate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, and calcium zirconate. These may be used individually by 1 type and may use 2 or more types together. Among these, silica is preferable from the viewpoint of lowering thermal expansion.

  There is no restriction | limiting in particular in the shape of an inorganic filler (a2), For example, any of spherical shape, crushed shape, needle shape, or plate shape may be sufficient, but the dispersibility improvement in a resin composition, a resin composition in an organic solvent From the viewpoint of improving the dispersibility in the resin varnish in which the resin is dissolved or dispersed, improving the fluidity by reducing the viscosity of the resin varnish, and suppressing the increase in the surface roughness of the insulating layer formed from the resin composition, it may be spherical. preferable.

Although the volume average particle diameter of an inorganic filler (a2) is not specifically limited, For example, 0.05-5 micrometers is preferable, 0.1-3 micrometers is more preferable, 0.2-1 micrometer is further more preferable. If the volume average particle diameter of the component (a2) is 5 μm or less, the fine pattern tends to be formed more stably when the circuit pattern is formed on the interlayer insulating layer. Moreover, if the volume average particle diameter of the inorganic filler (a2) is 0.1 μm or more, the heat resistance tends to be better.
The volume average particle diameter is a particle diameter at a point corresponding to a volume of 50% when the cumulative frequency distribution curve by the particle diameter is obtained with the total volume of the particles being 100%, and the laser diffraction scattering method is used. It can be measured with the used particle size distribution measuring device or the like.

Moreover, you may use a coupling agent together as needed for the purpose of improving the dispersibility of an inorganic filler (a2) and the adhesiveness of the inorganic filler (a2) and the organic component in a resin composition. It does not specifically limit as a coupling agent, For example, various silane coupling agents, a titanate coupling agent, etc. can be used. These may be used individually by 1 type and may use 2 or more types together. Among these, a silane coupling agent is preferable. Examples of the silane coupling agent include amino silane coupling agents, epoxy silane coupling agents, phenyl silane coupling agents, alkyl silane coupling agents, alkenyl silane coupling agents, mercapto silane coupling agents, and the like. It is done. Among these, an aminosilane coupling agent is preferable from the viewpoint of improving the dispersibility of the inorganic filler (a2) and improving the adhesion between the inorganic filler (a2) and the organic component.
Moreover, when using a coupling agent, although the usage-amount is not specifically limited, 0.1-5 mass parts is preferable with respect to 100 mass parts of inorganic fillers (a2), and 0.5-3 mass parts is more. preferable. If it is this range, the characteristic by use of an inorganic filler (a2) can be exhibited more effectively.
In the case of using a coupling agent, the addition method may be a so-called integral blend treatment method in which a coupling agent is added after blending the inorganic filler (a2) in the resin composition, or more effective. In particular, from the viewpoint of manifesting the characteristics of the inorganic filler (a2), a system in which a coupling agent is surface-treated in advance by dry or wet with respect to the inorganic filler before blending may be used.

The inorganic filler (a2) is preferably used in the form of a slurry previously dispersed in an organic solvent from the viewpoint of enhancing the dispersibility in the resin composition. Although there is no restriction | limiting in particular in the organic solvent used for the slurry of an inorganic filler (a2), For example, the organic solvent illustrated by the manufacturing process of the polyimide compound (a1) mentioned above is applicable. These may be used individually by 1 type and may use 2 or more types together. Among these organic solvents, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone are preferable from the viewpoint of further improving dispersibility.
Although there is no restriction | limiting in particular in the solid content density | concentration of the slurry of an inorganic filler (a2), For example, 50-80 mass% is preferable from a viewpoint of the sedimentation property and dispersibility of an inorganic filler (a2), and 60-80 mass%. Is more preferable.
Although content of an inorganic filler (a2) can be suitably selected with the characteristic and function to obtain | require, 55 volume% or more is preferable with respect to solid content of a resin composition, 55-85 volume% is more preferable, and 55-80 Volume% is more preferable, and 55 to 75 volume% is particularly preferable. By setting the content of the inorganic filler in such a range, it can have a low coefficient of thermal expansion.
In addition, in this specification, solid content contained in a resin composition means the residue which remove | excluded the volatile component from the component which comprises a resin composition.

<Elastomer (a3)>
The resin composition for the A layer may contain an elastomer (a3). The elastomer (a3) is not particularly limited. For example, polybutadiene-based elastomer, styrene-based elastomer, olefin-based elastomer, urethane-based elastomer, polyester-based elastomer, polyamide-based elastomer, acrylic-based elastomer, silicone-based elastomer, Derivatives and the like. These may be used individually by 1 type and may use 2 or more types together.

  As the elastomer (a3), those having a reactive functional group at the molecular end or molecular chain can be used. Examples of the reactive functional group include one or more selected from the group consisting of a maleic anhydride group, an epoxy group, a hydroxyl group, a carboxy group, an amino group, an amide group, an isocyanato group, an acrylic group, a methacryl group, and a vinyl group. Preferably, from the viewpoint of adhesion with the metal foil, it is more preferable that it is one or more selected from the group consisting of a maleic anhydride group, an epoxy group, a hydroxyl group, a carboxy group, an amino group, and an amide group. From the viewpoint of dielectric properties, a maleic anhydride group is more preferable. By having these reactive functional groups, compatibility with the resin is improved, and separation between the inorganic filler (a2) and the resin component when the interlayer insulating layer is formed tends to be suppressed. From the same viewpoint, the elastomer (a3) is preferably an elastomer modified with maleic anhydride.

A preferable example of the polybutadiene-based elastomer is a structure comprising a 1,4-trans isomer and a 1,4-cis isomer containing a 1,2-vinyl group.
Polybutadiene elastomers have reactive functional groups from the viewpoint of improving compatibility with resins and suppressing separation of the inorganic filler (a2) and resin components when an interlayer insulating layer is formed. A polybutadiene-based elastomer modified with an acid anhydride is particularly preferable. The acid anhydride is not particularly limited. For example, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl nadic anhydride, nadic anhydride, Examples include glutaric anhydride, dimethyl glutaric anhydride, diethyl glutaric anhydride, succinic anhydride, methyl hexahydrophthalic anhydride, methyl tetrahydrophthalic anhydride, and the like. Among these, maleic anhydride is preferable.
When the elastomer (a3) is modified with an acid anhydride, the number of acid anhydride-derived groups (hereinafter also referred to as “acid anhydride groups”) contained in one molecule of the elastomer (a3) is 1 to 10 Are preferable, 1-6 are more preferable, and 2-5 are more preferable. When the number of acid anhydride groups is 1 or more per molecule, separation of the inorganic filler (a2) and the resin component when the interlayer insulating layer is formed tends to be further suppressed. When the number of acid anhydride groups is 10 or less per molecule, the dielectric loss tangent of the resin composition tends to be lower. When the elastomer (a3) is modified with maleic anhydride, from the same viewpoint as described above, a group derived from maleic anhydride contained in one molecule of the elastomer (a3) (hereinafter also referred to as “maleic anhydride group”) 1-10 are preferable, 1-6 are more preferable, and 2-5 are more preferable.
The polybutadiene elastomer is available as a commercial product. Specific examples thereof include, for example, “POLYVEST (registered trademark) MA75”, “POLYVEST (registered trademark) EP MA120” (manufactured by Evonik, trade name), “Ricon (registered trademark) 130MA8”, “Ricon (registered trademark) 131MA5”, “Ricon (registered trademark) 184MA6” (trade name, manufactured by Clay Valley Co., Ltd.) and the like.

  Preferable examples of the styrenic elastomer include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, styrene-ethylene-butylene-styrene block copolymers, and styrene-ethylene-propylene-styrene block copolymers. Examples of components constituting the styrene elastomer include styrene derivatives such as α-methyl styrene, 3-methyl styrene, 4-propyl styrene, 4-cyclohexyl styrene, in addition to styrene. Styrenic elastomers are available as commercial products. Specific examples thereof include “Tufprene (registered trademark)”, “Asaprene (registered trademark) T”, “Tuftec (registered trademark) H”, and “Tuftec (registered trademark)”. ) MP10 "," Tuftec (registered trademark) M1911 "," Tuftec (registered trademark) M1913 "(manufactured by Asahi Kasei Chemicals Corporation)," Epofriend (registered trademark) AT501 "," Epofriend (registered trademark) CT310 " (Above, manufactured by Daicel Corporation).

  Examples of the olefin-based elastomer include copolymers of α-olefins having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-pentene, and the like. Preferred examples include a polymer (EPR) and an ethylene-propylene-diene copolymer (EPDM). Further, a copolymer of the α-olefin and a non-conjugated diene having 2 to 20 carbon atoms such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene, butadiene, or isoprene is exemplified. . Furthermore, a carboxy-modified NBR obtained by copolymerizing methacrylic acid with a butadiene-acrylonitrile copolymer is exemplified. Olefin-based elastomers are available as commercial products. Specific examples thereof include “PB3600”, “PB4700” (manufactured by Daicel Corporation), “G-1000”, “G-2000”, “G- 3000 "," JP-100 "," JP-200 "," BN-1015 "," TP-1001 "," TEA-1000 "," EA-3000 "," TE-2000 "," EMA-3000 " (Nippon Soda Co., Ltd.), “Denalex (registered trademark) R45” (manufactured by Nagase ChemteX Corporation), and the like.

Preferred examples of the urethane elastomer include those containing a hard segment composed of a short-chain diol and a diisocyanate and a soft segment composed of a polymer (long-chain) diol and a diisocyanate.
Examples of the polymer (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene-1,4-butylene adipate), polycaprolactone, and poly (1,6-hexene). Xylene carbonate), poly (1,6-hexylene, neopentylene adipate), and the like. The number average molecular weight of the polymer (long chain) diol is preferably 500 to 10,000.
Examples of the short chain diol include ethylene glycol, propylene glycol, 1,4-butanediol, and bisphenol A. The number average molecular weight of the short chain diol is preferably 48 to 500.
Urethane elastomers are available as commercial products. Specific examples thereof include “PANDEX (registered trademark) T-2185”, “PANDEX (registered trademark) T-2983N” (manufactured by DIC Corporation), and the like. Can be mentioned.

Examples of the polyester elastomer include those obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof.
Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of these aromatic nuclei are substituted with a methyl group, an ethyl group, a phenyl group, or the like; Examples thereof include aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid, and dodecanedicarboxylic acid; and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These compounds may be used individually by 1 type, and may use 2 or more types together.
Specific examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and 1,10-decanediol; 1,4-cyclohexanediol. And alicyclic diols such as bisphenol A, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3-methylphenyl) propane, and resorcin. These compounds may be used individually by 1 type, and may use 2 or more types together.

  As the polyester elastomer, a multi-block copolymer having an aromatic polyester (for example, polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion as a soft segment component is preferable. Can be mentioned. Multiblock copolymers are available in various grades depending on the type, ratio, and molecular weight of the hard segment and soft segment. Specific examples include “Hytrel” (registered trademark) (manufactured by Toray DuPont Co., Ltd.), “Perprene (registered trademark)” (manufactured by Toyobo Co., Ltd.), and “Espel (registered trademark)” (manufactured by Hitachi Chemical Co., Ltd.). Etc.

Examples of the polyamide-based elastomer include polyamide as a hard segment component, polybutadiene, butadiene-acrylonitrile copolymer, styrene-butadiene copolymer, polyisoprene, ethylene propylene copolymer, polyether, polyester, polybutadiene, polycarbonate, polyacrylate. And block copolymers containing polymethacrylate, polyurethane, silicone rubber and the like as soft segment components.
Polyamide elastomers are available as commercial products. Specific examples thereof include “UBE polyamide elastomer” (manufactured by Ube Industries, Ltd.), “Daiamide (registered trademark)” (manufactured by Daicel Evonik Co., Ltd.), “PEBAX”. (Registered trademark) "(manufactured by Toray Industries, Inc.)," Grillon (registered trademark) ELY "(manufactured by Ms. Chemie Japan)," Novamid (registered trademark) "(manufactured by Mitsubishi Chemical Corporation), ”” (Manufactured by DIC Corporation), “BPAM-01”, “BPAM-155” (manufactured by Nippon Kayaku Co., Ltd.) and the like.

  Examples of the acrylic elastomer include a polymer of a raw material monomer mainly composed of an acrylate ester. Preferable examples of the acrylic ester include ethyl acrylate, butyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate and the like. In addition, as a crosslinking point monomer, glycidyl methacrylate, allyl glycidyl ether or the like may be copolymerized, or acrylonitrile, ethylene or the like may be copolymerized. Specific examples include acrylonitrile-butyl acrylate copolymer, acrylonitrile-butyl acrylate-ethyl acrylate copolymer, acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer, and the like.

  Silicone elastomers are elastomers mainly composed of organopolysiloxane, and are classified into, for example, polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. Silicone elastomers are available as commercial products. Specific examples thereof include “X-22-163B”, “X-22-163C”, “X-22-1821”, “X-22-162C”. (Shin-Etsu Chemical Co., Ltd.), Core Shell Silicone Rubber “SY Series” (Asahi Kasei Wacker Silicone Co., Ltd.), “SE Series”, “CY Series”, “SH Series” (Toray Dow Corning Co., Ltd.) Company-made).

  Among these elastomers, styrene elastomers, polybutadiene elastomers, olefin elastomers, polyamide elastomers, and silicone elastomers are preferred from the viewpoint of heat resistance and insulation reliability, and polybutadiene elastomers and styrene series are preferred from the viewpoint of dielectric characteristics. Elastomers are more preferred, and polybutadiene elastomers are even more preferred.

  The weight average molecular weight of the elastomer (a3) is preferably 500 to 50,000, more preferably 1,000 to 30,000. When the weight average molecular weight of the elastomer (a3) is 500 or more, the curability of the resin composition and the dielectric properties of the cured product tend to be better. Further, when the weight average molecular weight of the elastomer (a3) is 50,000 or less, the separation between the inorganic filler (a2) and the resin component when the interlayer insulating layer is formed tends to be suppressed. In addition, the measuring method of the weight average molecular weight of a polyimide compound (a1) as described in an Example can be applied to the weight average molecular weight of an elastomer (a3).

  When the resin composition contains an elastomer (a3), the content is preferably 1 to 70% by mass, more preferably 5 to 50% by mass, and more preferably 10 to 30% with respect to the total resin components contained in the resin composition. More preferred is mass%. By setting the content of the elastomer (a3) within the above range, the dielectric loss tangent is low, the handleability when formed into a film is excellent, and the inorganic filler (a2) and the resin component when the interlayer insulating layer is formed It tends to be suppressed from separating.

<Other ingredients>
The resin composition for the A layer may contain a flame retardant, a curing accelerator and the like as necessary.
By including a flame retardant in the resin composition, better flame retardancy can be imparted. Although it does not specifically limit as a flame retardant, For example, a chlorine flame retardant, a bromine flame retardant, a phosphorus flame retardant, a metal hydrate flame retardant, etc. are mentioned. From the viewpoint of compatibility with the environment, phosphorus flame retardants and metal hydrate flame retardants are preferred.
Moreover, by including an appropriate curing accelerator in the resin composition, the curability of the resin composition can be improved, and the dielectric properties, heat resistance, high elastic modulus, glass transition temperature, and the like can be further improved. The curing accelerator is not particularly limited, and examples thereof include various imidazole compounds and derivatives thereof; various tertiary amine compounds; various quaternary ammonium compounds; various phosphorus compounds such as triphenylphosphine.
In addition, the resin composition may contain additives such as an antioxidant and a flow modifier.

(Resin varnish)
In the production of the A layer, it is preferable that the resin composition for the A layer is further added with an organic solvent to form a resin varnish (hereinafter also referred to as A layer varnish).
Examples of the organic solvent used for producing the varnish for layer A include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; acetates such as ethyl acetate, butyl acetate, cellosolve acetate, and carbitol acetate; cellosolve, (Di) ethylene glycol monoalkyl ether or propylene glycol monoalkyl ether such as butyl carbitol and propylene glycol monomethyl ether; aromatic hydrocarbon such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone and the like Examples thereof include amide solvents. These may be used individually by 1 type and may use 2 or more types together.
10-60 mass parts is preferable with respect to 100 mass parts of the whole varnish for A layers, and, as for content of an organic solvent, 10-35 mass parts is more preferable.
By using the A layer varnish thus produced, the composite film of the present invention can be produced as described above.

[Components of layer B]
A resin composition is mentioned as a component of B layer. The resin composition is not particularly limited as long as it improves the adhesion to the conductor layer. For example, from the viewpoint of excellent adhesion to plated copper even if the surface roughness is small, a polyfunctional epoxy resin A resin composition containing (b1) and a phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (b2) is preferred, and a resin composition containing an active ester curing agent (b3) is more preferred. Hereinafter, each component will be described in detail.

<Polyfunctional epoxy resin (b1)>
The polyfunctional epoxy resin (b1) is not particularly limited as long as it is a resin having two or more epoxy groups. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, cresol novolac type epoxy Resin, phenol novolac type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, aralkyl novolac type epoxy resin, fluorene type epoxy resin, xanthene type epoxy resin Etc. From the viewpoint of adhesiveness with plated copper, it is preferable to have a biphenyl structure, and a polyfunctional epoxy resin having a biphenyl structure or an aralkyl novolac type epoxy resin having a biphenyl structure is more preferable.
A polyfunctional epoxy resin (b1) may be used individually by 1 type, and may use 2 or more types together.

  A commercially available product may be used as the polyfunctional epoxy resin (b1). As the commercially available polyfunctional epoxy resin (b1), “NC-3000-H”, “NC-3000-L”, “NC” manufactured by Nippon Kayaku Co., Ltd., which is an aralkyl novolac type epoxy resin having a biphenyl structure. -3100 "," NC-3000 "and the like.

  Although it does not specifically limit as an epoxy equivalent of a polyfunctional epoxy resin (b1), From an adhesive viewpoint, 150-450 g / mol is preferable, 200-400 g / mol is more preferable, 250-350 g / mol is further more preferable.

  Although content of the polyfunctional epoxy resin (b1) in the resin composition for B layers is not specifically limited, 10-90 mass% is preferable with respect to all the resin components contained in a resin composition, and 20-80 More preferably, it is more preferably 30 to 70% by mass. If the content of the polyfunctional epoxy resin (b1) is 10% by mass or more, better adhesive strength with the plated copper tends to be obtained, and if it is 90% by mass or less, a lower dielectric loss tangent is obtained. It tends to be.

<Phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (b2)>
The component (b2) is not particularly limited as long as it is a polybutadiene-modified polyamide resin having a phenolic hydroxyl group, but a structural unit derived from a diamine, a structural unit derived from a dicarboxylic acid containing a phenolic hydroxyl group, and phenolic What has the structural unit derived from the dicarboxylic acid which does not contain a hydroxyl group, and the structural unit derived from the polybutadiene which has a carboxy group in the both terminal is preferable. Specifically, preferred are those having a structural unit represented by the following general formula (i), a structural unit represented by the following general formula (ii), and a structural unit represented by the following general formula (iii). .

In the general formulas (i) to (iii), a, b, c, x, y and z are integers indicating the average degree of polymerization, respectively, and a = 2 to 10, b = 0 to 3, c = 3 Y + z = 2 to 300 ((y + z) / x) for ˜30, x = 1, and z ≧ 20 (z / y) for y = 1.
In general formulas (i) to (iii), each R ′ independently represents a divalent group derived from an aromatic diamine or an aliphatic diamine, and in general formula (iii), R ″ represents an aromatic dicarboxylic acid. , A divalent group derived from an aliphatic dicarboxylic acid or an oligomer having a carboxy group at both ends.
A plurality of R ′ contained in the general formulas (i) to (iii) may be the same or different. When z is an integer of 2 or more, the plurality of R ″ may be the same or different.
In general formulas (i) to (iii), R ′ is specifically a divalent group derived from an aromatic diamine or aliphatic diamine described later, and R ″ is an aromatic described later. It is preferably a divalent group derived from dicarboxylic acid, aliphatic dicarboxylic acid or an oligomer having a carboxy group at both ends.

Examples of the diamine used for forming a structural unit derived from diamine in the component (b2) include aromatic diamine and aliphatic diamine.
Examples of the aromatic diamine include diaminobenzene, diaminotoluene, diaminophenol, diaminodimethylbenzene, diaminomesitylene, diaminonitrobenzene, diaminodiazobenzene, diaminonaphthalene, diaminobiphenyl, diaminodimethoxybiphenyl, diaminodiphenyl ether, diaminodimethyldiphenyl ether, methylene Diamine, methylenebis (dimethylaniline), methylenebis (methoxyaniline), methylenebis (dimethoxyaniline), methylenebis (ethylaniline), methylenebis (diethylaniline), methylenebis (ethoxyaniline), methylenebis (diethoxyaniline), isopropylidenedianiline, Diaminobenzophenone, diaminodimethylbenzophenone, dia Bruno anthraquinone, diamino diphenyl thioether, diaminodiphenyl dimethyl diphenyl thioether, diaminodiphenyl sulfone, diaminodiphenyl sulfoxide, diaminofluorene and the like.

  Examples of the aliphatic diamine include ethylenediamine, propanediamine, hydroxypropanediamine, butanediamine, heptanediamine, hexanediamine, cyclopentanediamine, cyclohexanediamine, azapentanediamine, and triazaundecadiamine.

Examples of the dicarboxylic acid containing a phenolic hydroxyl group used for forming the “structural unit derived from a dicarboxylic acid containing a phenolic hydroxyl group” included in the component (b2) include hydroxyisophthalic acid, hydroxyphthalic acid, hydroxyterephthalate. Examples include acids, dihydroxyisophthalic acid, and dihydroxyterephthalic acid.
Examples of the dicarboxylic acid not containing a phenolic hydroxyl group used to form the “structural unit derived from a dicarboxylic acid not containing a phenolic hydroxyl group” included in the component (b2) include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, Examples include oligomers having a carboxy group at both ends.
Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, biphenyl dicarboxylic acid, methylene dibenzoic acid, thiodibenzoic acid, carbonyl dibenzoic acid, sulfonylbenzoic acid, and naphthalenedicarboxylic acid.
Examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, methylmalonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, malic acid, tartaric acid, (meth) acryloyloxysuccinic acid, di (meta) ) Acryloyloxysuccinic acid, (meth) acryloyloxymalic acid, (meth) acrylamide succinic acid, (meth) acrylamide malic acid and the like.

  Although there is no restriction | limiting in particular in the weight average molecular weight of a component (b2), For example, it is preferable that it is 60,000-250,000, and it is more preferable that it is 80,000-200,000. The weight average molecular weight of a component (b2) can be calculated | required by the method similar to the weight average molecular weight of the said polyimide compound (a1).

  The active hydroxyl group equivalent of component (b2) is not particularly limited, but is preferably 1,500 to 7,000 g / mol, more preferably 2,000 to 6,000 g / mol, and 3,000 to 5,000 g / mol. Is more preferable.

  Component (b2) includes, for example, diamine, dicarboxylic acid containing a phenolic hydroxyl group, dicarboxylic acid not containing a phenolic hydroxyl group, and polybutadiene having a carboxy group at both ends in an organic solvent such as dimethylacetamide. And synthesized by polycondensation of a carboxy group and an amino group by reacting in the presence of a phosphite ester and a pyridine derivative as a catalyst. Examples of the compounds that can be used for the production include those described above.

  The polybutadiene having carboxy groups at both ends used for the production of the component (b2) is, for example, preferably an oligomer having a number average molecular weight of 200 to 10,000 and a number average molecular weight of 500 to 5,000. It is more preferable.

  A commercially available product can be used as the component (b2), and examples of the commercially available component (b2) include “BPAM-155” manufactured by Nippon Kayaku Co., Ltd.

  Although content of the component (b2) in the resin composition for B layers is not specifically limited, 1-20 mass% is preferable with respect to all the resin components contained in a resin composition, and 2-15 mass% is more. Preferably, 3-10 mass% is more preferable. When the content of the component (b2) is 1% by mass or more, the toughness of the resin composition can be increased, a dense roughened shape can be obtained, and the adhesion to the plated copper can be enhanced. . Moreover, if it is 20 mass% or less, there will be no heat resistance fall and the fall with respect to the chemical | medical solution at the time of a roughening process can also be prevented. Moreover, sufficient adhesiveness with plated copper can be ensured.

<Active ester curing agent (b3)>
The active ester curing agent (b3) has one or more ester groups in one molecule and has an epoxy resin curing action.
Although it does not specifically limit as an active ester hardening | curing agent (b3), For example, the ester compound etc. which are obtained from an aliphatic or aromatic carboxylic acid and an aliphatic or aromatic hydroxy compound are mentioned.
Among these, ester compounds obtained from aliphatic carboxylic acids, aliphatic hydroxy compounds, and the like tend to have high solubility in organic solvents and compatibility with epoxy resins by including aliphatic chains.
Moreover, the ester compound obtained from aromatic carboxylic acid, an aromatic hydroxy compound, etc. exists in the tendency for heat resistance to be improved by having an aromatic ring.

Examples of the active ester curing agent (b3) include phenol ester compounds, thiophenol ester compounds, N-hydroxyamine ester compounds, esterified compounds of heterocyclic hydroxy compounds, and the like.
More specifically, for example, aromatic esters obtained by a condensation reaction of an aromatic carboxylic acid and a phenolic hydroxyl group can be mentioned, and aromatics such as benzene, naphthalene, biphenyl, diphenylpropane, diphenylmethane, diphenyl ether, diphenylsulfonic acid and the like can be mentioned. An aromatic carboxylic acid component selected from those in which 2 to 4 of the hydrogen atoms in the ring are substituted with carboxy groups; a monovalent phenol in which one of the hydrogen atoms in the aromatic ring is substituted with a hydroxyl group; and a hydrogen atom in the aromatic ring Aromatic esters obtained by a condensation reaction of an aromatic carboxylic acid and a phenolic hydroxyl group using a mixture of 2 to 4 of the above with a polyhydric phenol substituted with a hydroxyl group is preferred. That is, an aromatic ester having a structural unit derived from the aromatic carboxylic acid component, a structural unit derived from the monohydric phenol, and a structural unit derived from the polyhydric phenol is preferable.

A commercially available product may be used as the active ester curing agent (b3). Commercially available products of the active ester curing agent (b3) include, for example, “EXB9451”, “EXB9460”, “EXB9460S”, “HPC-8000-65T” (DIC) as active ester compounds containing a dicyclopentadiene type diphenol structure. Co., Ltd.), “EXB9416-70BK” (manufactured by DIC Corporation) as an active ester compound containing a naphthalene structure, “DC808” (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing an acetylated product of phenol novolac, Examples of the active ester compound containing a benzoylated product include “YLH1026” (manufactured by Mitsubishi Chemical Corporation).
An active ester hardening agent (b3) may be used individually by 1 type, and may use 2 or more types together.

  The ester equivalent of the active ester curing agent (b3) is not particularly limited, but is preferably 150 to 400 g / mol, more preferably 170 to 300 g / mol, and further preferably 200 to 250 g / mol.

  The equivalent ratio (ester group / epoxy group) of the ester group of the active ester curing agent (b3) to the epoxy group of the polyfunctional epoxy resin (b1) in the resin composition is preferably 0.05 to 1.5, 0 0.1 to 1.3 is more preferable, and 0.2 to 1.0 is more preferable. If the equivalent ratio (ester group / epoxy group) is within the above range, the adhesive strength with the plated copper can be further increased, and a lower dielectric loss tangent and a smooth surface can be obtained. is there.

<Phosphorus curing accelerator (b4)>
It is preferable that the resin composition for the B layer further contains a phosphorus-based curing accelerator (b4).
As a phosphorus hardening accelerator (b4), if it is a hardening accelerator which contains a phosphorus atom and accelerates | stimulates reaction with a polyfunctional epoxy resin (b1) and an active ester hardening agent (b3), it will be used without a restriction | limiting. Can do.
By containing the phosphorus-based curing accelerator (b4), the resin composition can further promote the curing reaction. The reason for this is that by using the phosphorus-based curing accelerator (b4), the electron withdrawing property of the carbonyl group in the active ester curing agent (b3) can be enhanced. It is assumed that the reaction with the functional epoxy resin (b1) is promoted.
As described above, the resin composition contains the phosphorus-based curing accelerator (b4), so that the polyfunctional epoxy resin (b1) and the active ester curing agent (b3) are used more than when other curing accelerators are used. Since the curing reaction proceeds more sufficiently, it is considered that a low dielectric loss tangent can be obtained when combined with the first resin layer.

Examples of the phosphorus curing accelerator (b4) include triphenylphosphine, diphenyl (alkylphenyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) phosphine, tris (alkylalkoxyphenyl) phosphine, and tris (dialkylphenyl). ) Phosphine, tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, dialkylarylphosphine Organic phosphines such as alkyl diaryl phosphines; complexes of organic phosphines with organic borons; tertiary phosphines and quinones Such as the addition thereof. From the viewpoint that the curing reaction proceeds more sufficiently and can exhibit high adhesiveness with plated copper, an adduct of a tertiary phosphine and a quinone is preferable.
The tertiary phosphine is not particularly limited. For example, tri-n-butylphosphine, dibutylphenylphosphine, butyldiphenylphosphine, ethyldiphenylphosphine, triphenylphosphine, tris (4-methylphenyl) phosphine, tris (4- And methoxyphenyl) phosphine. Examples of quinones include o-benzoquinone, p-benzoquinone, diphenoquinone, 1,4-naphthoquinone, and anthraquinone. An adduct of tri-n-butylphosphine and p-benzoquinone is more preferred from the viewpoints of adhesion to plated copper, heat resistance, and a smooth surface.

  As a method for producing an adduct of a tertiary phosphine and a quinone, for example, the mixture is stirred and mixed in a solvent in which the tertiary phosphine and the quinone as raw materials are dissolved together, followed by addition reaction, and then isolated. And the like. As production conditions in this case, for example, tertiary phosphine and quinones are stirred in a solvent such as ketones such as methyl isobutyl ketone, methyl ethyl ketone and acetone in the range of 20 to 80 ° C. for 1 to 12 hours. It is preferable to carry out addition reaction.

  A phosphorus hardening accelerator (b4) may be used individually by 1 type, and may use 2 or more types together. Moreover, you may use together 1 or more types of hardening accelerators other than a phosphorus hardening accelerator (b4).

  Although content of the phosphorus hardening accelerator (b4) in the resin composition for B layers is not specifically limited, 0.1-20 mass% is preferable with respect to all the resin components contained in a resin composition, 0 2 to 15% by mass is more preferable, and 0.4 to 10% by mass is even more preferable. If the content of the phosphorus curing accelerator (b4) is 0.1% by mass or more, the curing reaction can be sufficiently advanced, and if it is 20% by mass or less, the homogeneity of the cured product can be maintained. .

<Filler (b5)>
The resin composition for the B layer may contain a filler (b5). Examples of the filler (H) include inorganic fillers and organic fillers. Among these, inorganic fillers are preferable.
By containing the filler (b5), the scattering of the resin can be further reduced when the B layer is laser processed.

Although it does not specifically limit as an inorganic filler, For example, the thing similar to what was illustrated as an inorganic filler (A) can be used.
The particle diameter of the inorganic filler is preferably small from the viewpoint of forming fine wiring on the B layer. From the same viewpoint, the specific surface area of the inorganic filler is preferably 20 m ² / g or more, and more preferably 50 m ² / g or more. Although there is no restriction | limiting in particular in the upper limit of a specific surface area, 500 m < ² > / g or less is preferable from a viewpoint of availability, and 200 m < ² > / g or less is more preferable.
The specific surface area can be determined by a BET method by low-temperature low-humidity physical adsorption of an inert gas. Specifically, molecules having a known adsorption occupation area such as nitrogen are adsorbed on the surface of the powder particles at the liquid nitrogen temperature, and the specific surface area of the powder particles can be determined from the amount of adsorption.
As the inorganic filler having a specific surface area of 20 m ² / g or more, a commercially available product may be used. Examples of commercially available products include fumed silica “AEROSIL (registered trademark) R972” (manufactured by Nippon Aerosil Co., Ltd., trade name, specific surface area 110 ± 20 m ² / g), “AEROSIL (registered trademark) R202” (Japan) Aerosil Co., Ltd., trade name, specific surface area 100 ± 20 m ² / g), colloidal silica “PL-1” (manufactured by Fuso Chemical Industry Co., Ltd., trade name, specific surface area 181 m ² / g), “PL-7 "(Manufactured by Fuso Chemical Industry Co., Ltd., trade name, specific surface area 36 m ² / g). Further, from the viewpoint of improving moisture resistance, an inorganic filler surface-treated with a surface treatment agent such as a silane coupling agent is preferable.

  The content of the inorganic filler in the resin composition for the B layer is preferably 1 to 30% by mass, more preferably 2 to 25% by mass, and 3 to 20% by mass with respect to the solid content of the resin composition. More preferably, 5-20 mass% is especially preferable. When the content of the inorganic filler is 1% by mass or more, better laser processability tends to be obtained, and when it is 30% by mass or less, the adhesion between the B layer and the conductor layer is further improved. There is a tendency.

  The organic filler is not particularly limited. For example, a crosslinked NBR particle obtained by copolymerizing acrylonitrile and butadiene, a copolymer of acrylonitrile butadiene such as a copolymer of acrylonitrile, butadiene and carboxylic acid such as acrylic acid; polybutadiene; And so-called core-shell rubber particles having NBR, silicone rubber or the like as a core and acrylic acid derivative as a shell. By containing the organic filler, the extensibility of the resin layer tends to be further improved.

<Other ingredients>
In addition to the above components, the resin composition for the B layer is not limited to the effects of the present invention, and other thermosetting resins, thermoplastic resins, and flame retardants, antioxidants, and fluids as necessary. Additives such as a regulator and a curing accelerator can be contained.

  In the composite film of the present invention, the 5 GHz dielectric loss tangent of the cured product is preferably 0.005 or less, and more preferably 0.0040 or less. Although there is no restriction | limiting in particular in a lower limit, 0.002 or more may be sufficient and 0.0030 or more may be sufficient. The dielectric loss tangent can be obtained by the method described in the examples.

[Printed wiring board and manufacturing method thereof]
The printed wiring board of the present invention contains a cured product of the composite film of the present invention. In other words, the printed wiring board of the present invention has an interlayer insulating layer, and at least one of the interlayer insulating layers contains the resin composition.

From the viewpoint of embedding and thinning, in the printed wiring board of the present invention, the thickness of the A layer is a (μm), the thickness of the B layer is b (μm), and the height of the circuit is c (μm). sometimes,
It is preferable to satisfy the relationship of c ≦ a ≦ 3c. It is more preferable to satisfy the relationship c ≦ a ≦ 2c, and it is even more preferable to satisfy the relationship c ≦ a ≦ 1.5c.

  In the printed wiring board of this invention, it is preferable that it is 1 <= b <= 10 from a viewpoint of exhibiting peel strength more, and a viewpoint of thickness reduction. 1 ≦ b ≦ 7 is more preferable, and 1 ≦ b ≦ 5 is still more preferable.

  Hereinafter, a method for producing a multilayer printed wiring board by laminating the composite film of the present invention on a circuit board will be described.

The manufacturing method of the multilayer printed wiring board of this invention has the following process (1). More specifically, the method for producing a multilayer printed wiring board of the present invention includes the following steps (1) to (5), and after step (1), step (2) or step (3): The support may be peeled off or removed.
Step (1): Step of laminating the composite film of the present invention on one or both sides of the circuit board Step (2): Step of thermosetting the composite film to form an interlayer insulating layer Step (3): Interlayer insulating layer Step of drilling the formed circuit board Step (4): Step of roughening the surface of the interlayer insulating layer Step (5): Step of plating on the surface of the roughened interlayer insulating layer

<Step (1)>
Step (1) is a step of laminating the composite film of the present invention on one or both sides of the circuit board. Examples of the apparatus for laminating the composite film include a vacuum laminator. Commercially available products can be used as the vacuum laminator. Examples of the commercially available vacuum laminator include a vacuum applicator manufactured by Nichigo-Morton Co., Ltd., a vacuum pressure laminator manufactured by Meiki Seisakusho Co., Ltd., and manufactured by Hitachi Industries, Ltd. And a roll laminator manufactured by Hitachi AIC Co., Ltd.

In the lamination, when the composite film has a protective film, after removing the protective film, the composite film is pressure-bonded to the circuit board while being pressurized and / or heated.
When using a composite film, it arrange | positions so that A layer may oppose the surface in which the circuit of the circuit board is formed.
The lamination conditions are as follows: the composite film and the circuit board are preheated as necessary, the pressure bonding temperature (laminating temperature) is 60 to 140 ° C., and the pressure bonding pressure is 0.1 to 1.1 MPa (9.8 × 10 4 to 10 7. 9 × 10 4 N / m ² ) and air pressure of 20 mmHg (26.7 hPa) or less may be laminated. The laminating method may be a batch method or a continuous method using a roll.
The substrate usually has a step due to a circuit or a component, but after the composite film of the present invention is laminated on the substrate, the step can be sufficiently filled with the A layer of the composite film. From the viewpoint of ensuring a sufficient degree of filling, the laminating temperature is particularly preferably 70 to 130 ° C.

<Step (2)>
Step (2) is a step of thermosetting the composite film to form an interlayer insulating layer. The conditions for heat curing are not particularly limited, but can be selected, for example, at 170 to 220 ° C. for 20 to 80 minutes. You may peel a support body, after making it thermoset.

<Step (3)>
Step (3) is a step of drilling a circuit board on which an interlayer insulating layer is formed. In this step, holes are drilled in the interlayer insulating layer and the circuit board by a method such as drilling, laser, plasma, or a combination thereof to form via holes, through holes, and the like. As the laser, a carbon dioxide laser, a YAG laser, a UV laser, an excimer laser or the like is generally used.

<Process (4)>
Step (4) is a step of roughening the surface of the interlayer insulating layer. In this step, the surface of the interlayer insulating layer formed in step (2) is roughened with an oxidizing agent, and at the same time, if via holes, through holes, etc. are formed, they are generated when these are formed. “Smear” removal can also be performed.
Although it does not specifically limit as an oxidizing agent, For example, permanganate (potassium permanganate, sodium permanganate), dichromate, ozone, hydrogen peroxide, sulfuric acid, nitric acid, etc. are mentioned. Among these, alkaline permanganate solutions (for example, potassium permanganate and sodium permanganate solutions), which are oxidizers commonly used for roughening interlayer insulation layers in the production of multilayer printed wiring boards by the build-up method, are used. It may be used for roughening and smear removal.

<Step (5)>
Step (5) is a step of plating the surface of the roughened interlayer insulating layer. The B layer of the composite film is a layer that can be applied to the semi-additive method. Therefore, in this step, a power feeding layer is formed on the surface of the interlayer insulating layer by electroless plating, then a plating resist having a pattern opposite to that of the conductor layer is formed, and a conductor layer (circuit) is formed by electrolytic plating. An additive method can be used.
In addition, after forming a conductor layer, the adhesive strength of an interlayer insulation layer and a conductor layer can be improved and stabilized by performing an annealing process at 150 to 200 ° C. for 20 to 120 minutes, for example.

  Furthermore, you may have the process of roughening the surface of the conductor layer produced in this way. The roughening of the surface of the conductor layer has the effect of improving the adhesion with the resin in contact with the conductor layer. The treatment agent for roughening the conductor layer is not particularly limited. For example, MEC etch bond CZ-8100, MEC etch bond CZ-8101, and MEC etch bond CZ-5480 (which are organic acid microetching agents) MEC Co., Ltd. product name).

Among the above manufacturing methods, the following method for manufacturing a printed wiring board is given as an example of a preferred embodiment because of the features of the present invention.
Using the composite film, attaching the A layer side of the composite film to a substrate having a step due to a circuit or a part on the surface, and filling the step.
Curing the A and B layers of the composite film;
Forming a circuit by a semi-additive method on the surface of the composite film on the B layer side;
A method for producing a printed wiring board, comprising:

  The composite film and printed wiring board of the present invention can be particularly suitably used for electronic devices that handle high-frequency signals of 1 GHz or higher. Particularly, electronic devices that handle high-frequency signals of 5 GHz or higher, high-frequency signals of 10 GHz or higher, or high-frequency signals of 30 GHz or higher. It can use suitably for an apparatus. That is, the composite film of the present invention is useful as a composite film for electronic equipment that uses signals in a high frequency band.

  In addition, this invention is not limited to the said embodiment. The above-described embodiment is an exemplification, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and has the same function and effect can be used. Included in the technical scope.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.

Production Example 1
<Production of polyimide compound (a1)>
1,6-bismaleimide- (2,2,4-trimethyl) hexane (manufactured by Daiwa Kasei Kogyo Co., Ltd.) was added to a 1 L glass flask container equipped with a thermometer, a reflux condenser, and a stirrer. , Trade name: BMI-TMH) 100 parts by mass, 2,2-bis [4- (4-maleimidophenoxy) phenyl] propane (manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name: BMI-4000), 418 parts by mass, 4 '-[1,3-phenylenebis (1-methylethylidene)] bisaniline (trade name: Bisaniline M manufactured by Mitsui Chemicals Fine Co., Ltd.) and 909 parts by mass of propylene glycol monomethyl ether were charged and refluxed. The mixture was reacted at a liquid temperature of 120 ° C. for 3 hours with stirring.
Then, it confirmed that the weight average molecular weight of the reaction material was 3,000 with the measuring method mentioned later, cooled and filtered 200 mesh, and manufactured the polyimide compound (a1) (solid content concentration: 65 mass%).

<Measurement method of weight average molecular weight>
The weight average molecular weight of the obtained polyimide compound (a1) was converted from a calibration curve using standard polystyrene by GPC. The calibration curve is standard polystyrene: TSK standard POLYSTYRENE (Type; A-2500, A-5000, F-1, F-2, F-4, F-10, F-20, F-40) [manufactured by Tosoh Corporation, Product name]) and approximated by a cubic equation. The GPC conditions are shown below.
Apparatus: (Pump: L-6200 type [manufactured by Hitachi High-Technologies Corporation])
(Detector: L-3300 type RI [manufactured by Hitachi High-Technologies Corporation])
(Column oven: L-655A-52 [manufactured by Hitachi High-Technologies Corporation])
Column: guard column; TSK Guardcolumn HHR-L + column; TSK gel-G4000HHR + TSK gel-G2000HHR (all trade names, manufactured by Tosoh Corporation)
Column size: 6.0 × 40 mm (guard column), 7.8 × 300 mm (column)
Eluent: Tetrahydrofuran Sample concentration: 30 mg / 5 mL
Injection volume: 20 μL
Flow rate: 1.00 mL / min Measurement temperature: 40 ° C

<Method for producing varnish for resin layer A (varnish A)>
Silica treated with an aminosilane coupling agent as an inorganic filler (a2) (manufactured by Admatechs Co., Ltd., trade name: SC-2050-KNK, methyl isobutyl ketone dispersion with a solid content of 70% by mass) and elastomer (B ) As a polybutadiene elastomer (trade name: POLYVEST 75MA, manufactured by Evonik Co., Ltd.), and the content of the inorganic filler (a2) is 76.9% by mass with respect to 100% by mass of the solid content contained in the resin composition. The elastomer (B) was mixed at a blending ratio of 4.3% by mass with respect to 100% by mass of the solid content contained in the resin composition.
The polyimide compound (a1) produced in Production Example 1 was mixed at a ratio that the content of the polyimide compound (a1) was 17% by mass with respect to 100% by mass of the solid content contained in the resin composition, It was dissolved at room temperature with a high-speed rotary mixer.
After visually confirming that the polyimide compound (a1) was dissolved, 1,3-phenylenebis (di-2,6-xylenyl phosphate) (made by Daihachi Chemical Industry Co., Ltd., trade name: PX-) as a flame retardant 200) 1.0% by mass, 4,4′-butylidenebis- (6-tert-butyl-3-methylphenol) as an antioxidant (manufactured by Mitsubishi Chemical Corporation, trade name: Yoshinox BB) (hereinafter referred to as Yoshinox BB) (Abbreviated) was 0.1% by mass, and “BYK310” (trade name, xylene solution having a solid content concentration of 25% by mass) 0.1% by mass (solid content) was mixed as a flow regulator. Thereafter, as a curing accelerator, an organic peroxide (manufactured by NOF Corporation, trade name: perbutyl P), a raw material (bismaleimide) converted from the charged amount of the polyimide compound (a1) and a polybutadiene-based elastomer (B) 1.0 phr, isocyanate mask imidazole (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: G8009L) is mixed with 0.5 phr with respect to the raw material aliphatic maleimide converted from the charged amount of the polyimide compound (a1). did. Subsequently, it disperse | distributed by the nanomizer process and the varnish A for producing the resin film for interlayer insulation was obtained.

  Varnishes B to D for producing resin films for interlayer insulation were obtained in the same manner as varnish A except that the components and the blending amounts thereof were changed to the blends shown in Table 1.

<Method for producing varnish for resin layer of layer B>
6.4% by mass of a phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (manufactured by Nippon Kayaku Co., Ltd., trade name: BPAM-155) with respect to 100% by mass of the solid content contained in the resin composition is 1% by mass. It was dissolved in a mixed solvent of dimethylacetamide and cyclohexanone (a mixed solvent having a mass ratio of dimethylacetamide: cyclohexanone of 7: 3) so as to be 6%. After dissolution, 57.2% by mass of aralkyl novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name: NC-3000H, epoxy equivalent 289 g / mol) with respect to 100% by mass of the solid content contained in the resin composition. , 8.8% by mass of an inorganic filler (manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil R972, specific surface area 110 ± 20 m 2 / g) with respect to 100% by mass of the solid content contained in the resin composition, 0.4 mass% phenoxy resin (trade name: YX7200, manufactured by Mitsubishi Chemical Corporation), based on 100 mass% solid content in the resin composition, manufactured by API Corporation, trade name: Yoshinox BB) The diluted product (35% by mass)) is 9.1% by mass in terms of solid content, 100% by mass based on 100% by mass of the solid content contained in the resin composition. Tell curing agent (manufactured by DIC Corporation, trade name: HPC-8000-65T (toluene diluted product (65% by mass)) with respect to 100% by mass of solid content contained in the resin composition is 14.6 in terms of solid content. % By mass, flow control agent (by Big Chemie Japan, trade name: BYK-310 (same as that used at the time of varnish A production)), 100% by mass of solid content contained in the resin composition 0.1 mass%, phosphorus-based curing accelerator (adduct of tri-normal butyl phosphine and p-benzoquinone) is mixed and dissolved in 3.4 mass% with respect to 100 mass% of the solid content contained in the resin composition. The varnish was diluted with methyl ethyl ketone so that the solid content concentration was 18% by mass, and then dispersed by nanomizer treatment to obtain a resin layer varnish for layer B.

<Manufacture of resin film for interlayer insulation>
Example 1
The varnish for the resin layer of the B layer obtained above is dried on a support (PET film, manufactured by Toray Film Processing Co., Ltd., trade name: Therapy SY (RX) (thickness 38 μm)). The B layer was applied using a comma coater so that the thickness was 2.5 μm, and dried at 140 ° C. for 3 minutes to form a B layer resin layer on the support. Next, the resin varnish A for layer A is applied onto the resin layer B using a comma coater so that the thickness of the resin layer A after drying is 27.5 μm. Dry at 2 ° C. for 2 minutes. Next, a 15 μm-thick polypropylene film as a protective film was wound on the surface of the A-layer resin layer in a roll shape to obtain an interlayer insulating resin film 1 having a support and a protective film.

Examples 2-5, Comparative Examples 1-3
Resin films 2 to 4 for interlayer insulation were obtained in the same manner as Example 1 using the varnish A2 for the resin layer A.

[Production of resin plate]
The resin plate used for the measurement of dielectric loss tangent was produced by the following procedure.
(I) After peeling a protective film from the resin film for interlayer insulation which has the support body and protective film which were obtained in Examples 1-3 and the comparative example 1, it dried at 120 degreeC for 3 minute (s).
Next, the resin film for interlayer insulation which has the support body after drying is made into copper foil (electrolytic copper foil) using a vacuum pressurization type laminator (made by Meiki Seisakusho Co., Ltd., trade name: MVLP-500 / 600-II). , 35 μm thick) on the glossy surface so that the interlayer insulating resin film and the copper foil are in contact with each other, and the laminated body in which the copper foil, the interlayer insulating resin film, and the support are laminated in this order (P ) The laminating was performed by a method in which the pressure was reduced to 0.5 MPa by reducing the pressure for 30 seconds and then pressing at 120 ° C. for 30 seconds at a pressure of 0.5 MPa. Then, the support body was peeled from the laminated body (P).
(II) Next, an interlayer insulating resin film having a PET film as a support and a polypropylene film as a protective film was prepared, and the protective film was peeled off, followed by drying at 110 ° C. for 3 minutes.
(III) Next, the laminate (P) from which the support obtained in (I) above was peeled off and the interlayer insulating resin film having the dried support obtained in (II) above were Laminate (Q) laminated with copper foil, two layers of interlayer insulating resin films, and a support laminated in this order so that the insulating resin films are in contact with each other under the same conditions as in (I) above. ) Thereafter, the support was peeled from the laminate (Q).
(IV) Next, an interlayer insulating resin film having a laminate (Q) from which the support obtained in (III) has been peeled and a dried support obtained by the same method as in (II) above Are laminated under the same conditions as in the above (I) so that the interlayer insulating resin films are in contact with each other, and a layer of copper foil, three interlayer insulating resin films, and a support are laminated in this order. A laminate (R) was obtained.
(V) A laminate (Q) was produced by the same method as in the above (I) to (III).
(VI) The laminate (Q) obtained in the above (V) and the support of the laminate (R) obtained in the above (I) to (IV) are peeled off, and the laminate (Q) and the laminate are laminated. The resin films for interlayer insulation of the body (R) were bonded together, and press molding was performed using a vacuum press at 190 ° C. for 60 minutes at a pressure of 3.0 MPa. After the obtained resin plate with double-sided copper foil was cured at 190 ° C. for 2 hours, the copper foil was etched with ammonium persulfate to obtain a resin plate.

[Measurement method of dielectric loss tangent]
The resin plate produced above is cut into a test piece having a width of 2 mm and a length of 70 mm, and a network analyzer (manufactured by Agilent Technologies, trade name: E8364B) and a cavity resonator for 5 GHz (manufactured by Kanto Electronics Application Development Co., Ltd.) Was used to measure the dielectric loss tangent. The measurement temperature was 25 ° C. The evaluation results are shown in Table 1. A lower dielectric loss tangent indicates better dielectric properties.

[Method for evaluating melt viscosity]
The film which produced A layer and B layer independently was used. A single layer sheet whose thickness was adjusted to 130 μm or more and less than 260 μm by laminating the prepared film was cut into 10 mm × 10 mm. When the thickness of the single film was less than 130 μm, a plurality of sheets were laminated so as to be 130 μm or more. Bonding is performed at a temperature at which curing does not proceed so that peeling does not occur on the bonding surface during shear viscosity measurement. The shear viscosity is 30 at a frequency of 1 Hz and a strain of 1%, using a rotary rheometer (TA Instruments, ARES), sandwiching the film between parallel disks (diameter 8 mm) with a gap width 2 to 5 μm smaller than the film thickness. It is the value of the complex viscosity when measured from ℃ to 300 ℃ (temperature increase rate: 5 ℃ / min).

[Substrate preparation method for surface roughness evaluation]
A substrate for surface roughness evaluation was prepared by the following procedure.
After the resin film for interlayer insulation which has the support body and protective film which were obtained in Examples 1-3 and the comparative example 1 was cut | disconnected to the size of 240 mm x 240 mm, the protective film was peeled.
The resin film for interlayer insulation having the obtained support is placed on a printed wiring board (trade name: E-700GR, manufactured by Hitachi Chemical Co., Ltd.) subjected to CZ treatment, Were laminated so that they contact each other. Lamination was performed by reducing the pressure at 120 ° C. for 30 seconds to a pressure of 0.5 MPa, and then pressing at 120 ° C. for 30 seconds at a pressure of 0.5 MPa.
Then, it cooled to room temperature and obtained the printed wiring board which distribute | arranged the resin film for interlayer insulation. Next, the printed wiring board on which the interlayer insulating resin film is disposed is cured in an explosion-proof dryer at 130 ° C. for 20 minutes for 60 minutes as the first stage curing with the support attached, and then the first stage Curing was performed in an explosion-proof dryer at 190 ° C. for 40 minutes to obtain a printed wiring board on which an interlayer insulating layer was formed. Thereafter, the support was peeled off to obtain a printed wiring board.

[Roughening method]
The test piece obtained above was immersed in a swelling liquid heated to 60 ° C. (Rohm and Haas Electronic Materials, trade name: CIRCUPOSIT MLB CONDITIONER 211) for 10 minutes. Next, it was immersed in a roughening liquid (Rohm and Haas Electronic Materials Co., Ltd., trade name: CIRCUPOSIT MLB PROMOTER 213) heated to 80 ° C. for 10 minutes. Subsequently, the mixture was neutralized by immersion for 5 minutes in a neutralizing solution heated to 45 ° C. (Rohm and Haas Electronic Materials Co., Ltd., trade name: CIRCUPOSIT MLB NEUTRALIZER MLB216). Thus, what roughened the surface of the interlayer insulation layer of the said test piece was used as a substrate for surface roughness measurement.

[Surface roughness measurement method]
The surface roughness of the substrate for measuring surface roughness obtained above was measured using a specific contact type surface roughness meter (Bruker AXS Co., Ltd., trade name: wykoNT9100), 1x internal lens, 50x external lens. Was used to obtain arithmetic average roughness (Ra). The evaluation results are shown in Table 1. From the gist of the present invention, Ra is preferably small, and if it is less than 200 nm, it is suitable for forming fine wiring.

[Adhesion strength with plated copper (plating peel strength) production method]
In carrying out the adhesive strength evaluation with the plated copper and the reflow heat resistance evaluation, an evaluation substrate was prepared according to the following procedure.
First, the printed wiring board with the resin film for interlayer insulation produced by the method similar to the above was cut out to 40 mm x 60 mm, and it was set as the test piece.
After roughening the test piece in the same manner as the substrate for measuring the surface roughness, the test piece was treated with an alkali cleaner (manufactured by Atotech Japan Co., Ltd., trade name: Cleaner Securigant 902) for 5 minutes, and degreased and washed. did. After washing, it was treated with a 23 ° C. pre-dip solution (manufactured by Atotech Japan Co., Ltd., trade name: Pre-dip Neo Gant B) for 2 minutes. Then, it processed for 5 minutes with the 40 degreeC activator liquid (Atotech Japan Co., Ltd. make, brand name: Activator Neogant 834), and the palladium catalyst was made to adhere. Next, it processed for 5 minutes with a 30 degreeC reducing liquid (Atotech Japan Co., Ltd. make, brand name: Reducer Neogant WA).
The test piece subjected to the above treatment is put into a chemical copper solution (manufactured by Atotech Japan Co., Ltd., trade name: Basic Print Gantt MSK-DK), and electroless plating is performed until the plating thickness on the interlayer insulating layer becomes 1 μm. Went. After the electroless plating, a baking treatment was performed at 120 ° C. for 15 minutes in order to relieve the stress remaining in the plating film and remove the remaining hydrogen gas.
Next, electrolytic plating was performed on the test piece subjected to the electroless plating treatment until the plating thickness on the interlayer insulating layer became 35 μm, and a copper layer was formed as a conductor layer. After the electrolytic plating, the substrate was heated and cured at 190 ° C. for 120 minutes to obtain a measurement substrate before production of the adhesive strength measurement part.
A 10 mm wide resist was formed on the copper layer, and the copper layer was etched with ammonium persulfate to obtain a substrate for measuring adhesive strength with plated copper having a 10 mm wide copper layer as an adhesive strength measuring part.

[Measurement method of adhesive strength with plated copper]
Using the adhesive strength measuring substrate obtained as described above, the adhesive strength between the interlayer insulating layer and the copper layer was measured by the following method.
One end of the copper layer of the adhesive strength measuring section is peeled off at the interface between the copper layer and the interlayer insulating layer and is gripped with a gripper, and vertically using a small tabletop testing machine (manufactured by Shimadzu Corporation, trade name: EZT Test). The load when it was peeled off at room temperature at a pulling speed of 50 mm / min in the direction was measured.

[Evaluation method of unevenness embedding]
The composite film obtained in each example was cut into a size of 240 mm × 240 mm, and then the protective film was peeled off.
On the printed wiring board (trade name: E-700GR, manufactured by Hitachi Chemical Co., Ltd.) on which the obtained composite film (with support) is formed with both a copper wiring with a thickness of 18 μm and a width of 5 mm and a copper wiring with a width of 100 μm. In addition, the first resin layer and the printed wiring board were laminated so as to contact each other. Lamination was performed by vacuuming at 100 ° C. for 15 seconds as the first stage, then pressing at 0.5 MPa for 45 seconds, and pressing at a pressure pressure of 0.5 MPa at 120 ° C. for 60 seconds as the second stage. Then, it cooled to room temperature and obtained the printed wiring board which distribute | arranged the composite film.
Next, the printed wiring board on which the composite film is arranged is cured in an explosion-proof dryer at 130 ° C. for 20 minutes as the first stage curing with the support attached, and then as the second stage curing. Curing was performed in an explosion-proof dryer at 190 ° C. for 40 minutes to obtain a printed wiring board on which an interlayer insulating layer was formed. Thereafter, the support was peeled off to obtain a printed wiring board.
The copper wiring portion of this printed wiring board is visually observed, and “○” indicates that the embedding property of both the 5 mm width copper wiring and the 100 μm width copper wiring is good, and “×” indicates that the embedding property is both bad. evaluated.

From Table 2, the printed wiring boards of Examples 2 and 3 using the thermosetting resin composition of the present embodiment have a small dielectric loss tangent and a smooth surface (low surface roughness (Ra)). It has an interlayer insulating layer excellent in adhesive strength with plated copper, and is found to be suitable for forming fine wiring.

  The interlayer insulation resin film for interlayer insulation of the present invention has a small dielectric loss tangent and excellent plating peel strength. Therefore, the thermosetting resin composition of the present invention, the resin film for interlayer insulation, and the printed wiring board are used in computers, mobile phones, digital cameras, televisions and other electrical products, motorcycles, automobiles, trains, ships, aircrafts, etc. Useful for vehicles.

DESCRIPTION OF SYMBOLS 1 1st resin layer 2 2nd resin layer 3 Support body 4 Protective film

Claims (9)

  A composite film for an electronic device, comprising an A layer and a B layer, and using a signal in a high frequency band in which the thickness of the B layer is 1 to 5 μm.   The composite film for electronic equipment using a signal in a high frequency band according to claim 1, wherein the thickness of the A layer is 10 to 40 µm. A composite film for electronic equipment, comprising an A layer and a B layer, and using a signal in a high frequency band in which the weight loss after desmearing of the B layer is 1 g / m ² or less.   The minimum melt viscosity at 80 to 150 ° C of the A layer is 100 to 5,000 Pa · s, and the minimum melt viscosity at 80 to 150 ° C of the B layer is 50,000 Pa · s or more. The composite film for electronic devices which uses the signal of the high frequency band as described in any one.   The electron which uses the signal of the high frequency band as described in any one of Claims 1-4 in which A layer contains the polyimide compound which has a structural unit derived from a maleimide compound, and a structural unit derived from a diamine compound, and an inorganic filler. Composite film for equipment.   The composite film for electronic devices using the signal of the high frequency band as described in any one of Claims 1-5 in which B layer contains a polyfunctional epoxy resin and a phenolic hydroxyl group containing polyamide resin.   The composite film for an electronic device using a signal in a high frequency band according to any one of claims 1 to 6, wherein a dielectric loss tangent at 5 GHz is 0.005 or less.   A printed wiring board having a cured product of a composite film for an electronic device using a signal in a high frequency band comprising an A layer and a B layer, and a circuit embedded in the A layer, the thickness of the A layer being a ( μm), a printed wiring board in which c ≦ a ≦ 3c and 1 ≦ b ≦ 10 when the thickness of the B layer is b (μm) and the height of the circuit is c (μm).   The manufacturing method of a printed wiring board provided with the process of laminating | stacking the composite film for electronic devices which uses the signal of the high frequency band of any one of Claims 1-7 on the single side | surface or both surfaces of a circuit board.

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