JP6801279B2 - Thermosetting resin composition, resin film for interlayer insulation, composite film, printed wiring board and its manufacturing method - Google Patents

Description

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

In recent years, electronic devices have become smaller, lighter, more multifunctional, etc., and along with this, LSI (Large Scale Integration), chip parts, etc. have become more integrated, and their forms have also become multi-pin and miniaturized. Is changing rapidly. Therefore, in order to improve the mounting density of electronic components, the development of fine wiring of multilayer printed wiring boards is underway. As a multilayer printed wiring board that meets these requirements, a multilayer printed wiring board with a build-up structure that uses an insulating resin film that does not contain glass cloth 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.

In addition, computers, information and telecommunications equipment, etc. have become more sophisticated and sophisticated in recent years, and in order to process a large amount of data at high speed, the signals to be handled tend to have higher frequencies. In particular, the frequency range of radio waves used for mobile phones and satellite broadcasting is in the high frequency range of the GHz band, and it is required to suppress transmission loss due to high frequency. Therefore, as an organic material used in a high frequency region, a material having a low relative permittivity and a dielectric loss tangent is desired.
In order to meet such demands, various efforts have been made for the build-up layer as well. For example, Patent Document 1 discloses a resin composition containing a cyanate resin.

On the other hand, the build-up layer is required to have low thermal expansion in order to improve the processing dimension stability and reduce the amount of warpage after semiconductor mounting. One of the methods for low thermal expansion of the build-up layer is a method of highly filling the filler. For example, by using 40% by mass or more of the build-up layer as a silica filler, the build-up layer can be reduced in thermal expansion (see, for example, Patent Documents 2 to 4).

Japanese Unexamined Patent Publication No. 2014-136779 JP-A-2007-87982 Japanese Unexamined Patent Publication No. 2009-280758 Japanese Unexamined Patent Publication No. 2005-39247

However, as a next-generation material, there is an increasing demand for a material having a lower dielectric loss tangent in a high frequency region than the resin composition disclosed in Patent Document 1. Further, as a next-generation material, there is an increasing demand for a material having a lower thermal expansion than the resin compositions disclosed in Patent Documents 2 to 4.
The present invention has been made in view of such a situation, and is suitable for a thermosetting resin composition having a low dielectric loss tangent, low thermal expansion, and excellent wire embedding property and flatness, and film handleability using the same. An object of the present invention is to provide a resin film for interlayer insulation, a composite film having excellent film handleability, a printed wiring board, and a method for manufacturing the same.

As a result of studying to solve the above problems, the present inventors have performed thermosetting containing an inorganic filler (A) containing a nanofiller (a), a thermosetting resin (B) and an elastomer (C). It has been found that the sex resin composition can solve the problem.
That is, the present invention provides the following [1] to [11].
[1] A thermosetting resin composition containing an inorganic filler (A) containing a nanofiller (a), a thermosetting resin (B), and an elastomer (C).
[2] The thermosetting resin composition according to the above [1], wherein the content of the nanofiller is 0.1 to 1.0% by mass with respect to the total amount of the inorganic filler (A).
[3] The thermosetting resin (B) is a polyimide compound having a structural unit derived from a maleimide compound (b1) having at least two N-substituted maleimide groups and a structural unit derived from a diamine compound (b2). The thermosetting resin composition according to [1] or [2].
[4] A resin film for interlayer insulation containing the thermosetting resin composition according to any one of the above [1] to [3].
[5] A composite film containing a first resin layer containing the thermosetting resin composition according to any one of the above [1] to [3] and a second resin layer.
[6] A second thermosetting resin composition in which the second resin layer contains a polyfunctional epoxy resin (D), an active ester curing agent (E), and a phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (F). The composite film according to the above [5].
[7] The equivalent ratio (ester group / epoxy group) of the ester group of the active ester curing agent (E) to the epoxy group of the polyfunctional epoxy resin (D) in the second thermosetting resin composition is 0.05. The composite film according to the above [6], which is ~ 1.5.
[8] The composite film according to the above [6] or [7], wherein the second thermosetting resin composition further contains a phosphorus-based curing accelerator (G).
[9] The composite film according to any one of [5] to [8] above, wherein the cured product has a 5 GHz dielectric loss tangent of 0.005 or less.
[10] A printed wiring board containing a cured product of the resin film for interlayer insulation according to the above [4] or a cured product of the composite film according to any one of the above [5] to [9].
[11] The step of laminating the resin film for interlayer insulation according to the above [4] or the composite film according to any one of the above [5] to [9] on one side or both sides of the base material is provided. Manufacturing method of printed wiring board.

According to the present invention, a thermosetting resin composition having a low dielectric loss tangent, low thermal expansion, and excellent wire embedding property and flatness, a resin film for interlayer insulation having excellent film handleability using the same, and film handleability. It is possible to provide an excellent composite film, a printed wiring board, and a method for manufacturing the same.

It is a figure which showed typically the composite film of this embodiment.

Hereinafter, the present embodiment will be described in detail. In this specification, a numerical range (X and Y are real numbers) that are greater than or equal to X and less than or equal to Y may be expressed as "X to Y". For example, the description "0.1 to 2" indicates a numerical range of 0.1 or more and 2 or less, and the numerical range includes 0.1, 0.34, 1.03, 2, and the like. Further, the present embodiment is only one embodiment of the present invention, and does not limit the present invention.

Further, in the present specification, the "resin composition" includes a mixture of each component described later and a semi-cured (so-called B-stage) mixture of the mixture.

Further, in the present specification, the "interlayer insulation layer" is a layer located between two conductor layers and for insulating the conductor layer. Examples of the "interlayer insulation layer" in the present specification include a cured product of a resin film for interlayer insulation, a cured product of a composite film, and the like. In addition, in this specification, a "layer" also includes a layer in which a part is missing, a via or a pattern is formed.

[Thermosetting resin composition]
The thermosetting resin composition of the present embodiment contains an inorganic filler (A) containing a nanofiller (a), a thermosetting resin (B), and an elastomer (C).

<Nanofiller (a)>
The nanofiller (a) refers to an inorganic filler having an average particle size of 300 nm or less. The nanofiller (a) is not particularly limited, and examples thereof include silica nanofiller, alumina nanofiller, and titanium oxide nanofiller. Silica nanofiller is preferable from the viewpoint of further reducing the coefficient of thermal expansion. .. Examples of silica nanofillers include spherical silica nanofillers, amorphous silica nanofillers, fused silica nanofillers, crystalline silica nanofillers, and synthetic silica nanofillers. The nanofiller (a) has improved dispersibility in the resin composition, improved dispersibility in the resin varnish in which the resin composition is dissolved or dispersed in an organic solvent, improved fluidity by reducing the viscosity of the resin varnish, and from the resin composition. From the viewpoint of suppressing an increase in the surface roughness of the insulating layer to be formed, it is preferable that the insulating layer is spherical.

The average particle size of the nanofiller (a) is preferably 200 nm or less, more preferably 100 nm or less. When the average particle size is 200 nm or less, the fluidity of the inorganic filler (A) containing the nanofiller (a) is good, and the wiring embedding property and surface flatness tend to be excellent. The average particle size of the nanofiller (a) is preferably 10 nm or more, more preferably 30 nm or more. When the average particle size of the inorganic filler (A) is 0.5 μm, the nanofiller (nanofiller) is the most improved in the fluidity of the inorganic filler (A) and has good wiring embedding property and surface flatness. Most preferably, nanosilica having an average particle size of 50 nm is used as a).

The content of the nanofiller (a) is preferably 0.1 to 1.0% by mass based on the total amount of the inorganic filler (A). When the resin composition is a resin varnish, the increase in varnish viscosity is suppressed and the handleability is improved. Therefore, the content of the nanofiller (a) is preferably 5.0% by mass or less, and 3.0% by mass. The following is more preferable, and 1.0% by mass or less is further preferable. When the content of the nanofiller (a) is 0.1% by mass or more, the fluidity of the inorganic filler (A) becomes good, and the wiring embedding property and the surface flatness tend to be improved.

From the viewpoint of enhancing the dispersibility of the nanofiller (a) in the thermosetting resin composition, it is preferable to use the nanofiller (a) as a slurry in which the nanofiller (a) is previously dispersed in an organic solvent, if necessary. The organic solvent used for slurrying the nanofiller (a) is not particularly limited, but for example, the organic solvent exemplified in the process for producing the thermosetting resin (B) described later can be applied. One of these may be used alone, or two or more thereof may be used in combination. Among these organic solvents, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone are preferable from the viewpoint of higher dispersibility.
The solid content concentration of the slurry of the nanofiller (a) is not particularly limited, but for example, from the viewpoint of sedimentation and dispersibility of the nanofiller (a), 30 to 80% by mass is preferable, and 40 to 80% by mass is preferable. More preferred.

<Inorganic filler (A)>
The inorganic filler (A) is not particularly limited, and for example, silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, etc. Examples thereof include aluminum borate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate and the like. One of these may be used alone, or two or more thereof may be used in combination. Among these, it is preferable to contain silica as the inorganic filler (A) from the viewpoint of further reducing the coefficient of thermal expansion. Examples of silica include spherical silica, amorphous silica, fused silica, crystalline silica, synthetic silica and the like.

The shape of the inorganic filler (A) may be spherical, crushed, needle-shaped or plate-shaped, but the dispersibility in the resin composition is improved, and the resin composition is dissolved or dispersed in an organic solvent. From the viewpoints of improving dispersibility in the resin varnish, improving fluidity by reducing the viscosity of the resin varnish, suppressing an increase in surface roughness of the insulating layer formed from the resin composition, and the like, the shape is preferably spherical.

The average particle size of the inorganic filler (A) is preferably 1 μm or less, more preferably 0.7 μm or less. When the average particle size of the inorganic filler (A) is 1 μm or less, the insulating layer formed from the resin composition tends to have excellent adhesiveness to plated copper. Further, from the viewpoint of suppressing an increase in viscosity and improving handleability when the resin composition containing the inorganic filler (A) is used as a resin varnish, the average particle size of the inorganic filler (A) is 0.01 μm. The above is preferable, 0.05 μm or more is more preferable, and 0.1 μm or more is further preferable. The average particle size is the particle size of a point corresponding to 50% of the volume when the cumulative frequency distribution curve based on the particle size is obtained, assuming that the total volume of the particles is 100%, and the laser diffraction scattering method is used. It can be measured with the particle size distribution measuring device or the like. In the present embodiment, when the particle size distribution is measured by the above method, the average particle size of the inorganic filler (A) is the sum of the nanofiller (a) and the inorganic filler other than the nanofiller (a). It may be calculated as the average particle size of the particle group. In this case, having a peak in the portion corresponding to the nanofiller (a) in the particle size distribution is considered to contain the nanofiller (a).

If necessary, a coupling agent may be used for the purpose of improving the dispersibility of the inorganic filler (A) and the adhesiveness between the inorganic filler (A) and the organic component in the thermosetting resin composition. .. The coupling agent is not particularly limited, and examples thereof include a silane coupling agent and a titanate coupling agent. Among these, a silane coupling agent is preferable. Examples of the silane coupling agent include aminosilane-based coupling agents, epoxysilane-based coupling agents, phenylsilane-based coupling agents, alkylsilane-based coupling agents, alkenylsilane-based coupling agents, and mercaptosilane-based coupling agents. Be done. Among these, an aminosilane-based coupling agent is preferable from the viewpoint of improving the dispersibility of the inorganic filler (A) and improving the adhesiveness between the inorganic filler (A) and the organic component. One of these may be used alone, or two or more thereof may be used in combination.
When a coupling agent is used, the amount used is not particularly limited, and for example, 0.1 to 5% by mass is preferable, and 0.5 to 3% by mass is more, based on the inorganic filler (A) to be used. preferable. Within this range, the features of using the inorganic filler (A) can be exhibited more effectively.

When a coupling agent is used, the addition method may be a so-called integral blend treatment method in which the inorganic filler (A) is added to the resin composition and then the coupling agent is added. From the viewpoint of effectively exhibiting the features of the inorganic filler (A), a method of surface-treating the inorganic filler before compounding with a dry or wet surface treatment is preferable.

The inorganic filler (A) is preferably used in the state of a slurry previously dispersed in an organic solvent from the viewpoint of enhancing the dispersibility in the thermosetting resin composition. The organic solvent used in the slurry of the inorganic filler (A) is not particularly limited, but for example, an organic solvent exemplified in the production process of the polyimide compound (B1) described later can be applied. One of these may be used alone, or two or more thereof may be used in combination. Among these organic solvents, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone are preferable from the viewpoint of higher dispersibility.

The solid content concentration of the slurry of the inorganic filler (A) is not particularly limited, but for example, from the viewpoint of sedimentation and dispersibility of the inorganic filler (A), 50 to 80% by mass is preferable, and 60 to 75% by mass is preferable. More preferred.

The content of the inorganic filler (A) can be appropriately selected depending on the characteristics and functions required for the thermosetting resin composition of the present embodiment, but is preferably 40 to 90% by mass in the solid content of the thermosetting resin composition. , 60-85% by mass, more preferably 65-80% by mass. By setting the content of the inorganic filler (A) in such a range, a low coefficient of thermal expansion can be obtained.
In the present specification, the solid content contained in the resin composition means a residue obtained by excluding volatile components from the components constituting the resin composition.

<Thermosetting resin (B)>
The thermosetting resin (B) is not particularly limited, and a polyimide resin, an epoxy resin, a cyanate resin, a maleimide resin, or the like can be used. Among these, maleimide resin is preferable, and from the viewpoint of exhibiting low thermal expansion, a polyimide having a structural unit derived from a maleimide compound (b1) having at least two N-substituted maleimide groups and a structural unit derived from a diamine compound (b2). A compound (hereinafter, also referred to as “polyimide compound (B1)”) is more preferable. The maleimide compound (b1) and the diamine compound (b2) having at least two N-substituted maleimide groups are not particularly limited.
The maleimide compound (b1) having at least two N-substituted maleimide groups (hereinafter, also referred to as “component (b1)”) is particularly limited as long as it is a maleimide compound having two or more N-substituted maleimide groups. It's not a thing.

The component (b1) is not particularly limited, and is, for example, bis (4-maleimidephenyl) methane, polyphenylmethane maleimide, bis (4-maleimidephenyl) ether, bis (4-maleimidephenyl) sulfone, 3,3'. -Dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, m-phenylenebismaleimide, 2,2-bis [4- (4-maleimidephenoxy) ) Phenyl] propane, 1,6-bismaleimide- (2,2,4-trimethyl) hexane and the like. One of these may be used alone, or two or more thereof may be used in combination. Among these, bis (4-maleimidephenyl) methane is preferable because it is inexpensive, and it has excellent dielectric properties and low water absorption. Therefore, 3,3'-dimethyl-5,5'-diethyl-4, 4'-Diphenylmethane bismaleimide is preferable, and 2,2-bis [4- (4-maleimide) is excellent in terms of high adhesiveness to a conductor, elongation of a cured product, mechanical properties such as breaking strength and elastic modulus, and dielectric properties. Phenoxy) phenyl] propane and 1,6-bismaleimide- (2,2,4-trimethyl) hexane are preferred.

Examples of the structural unit derived from the component (b1) 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 the general formulas (1-1) and (1-2), A ¹ indicates the residue of the component (b1), and * indicates the binding part.
The residue refers to the structure of a portion of the raw material component excluding the functional group (maleimide group in the component (b1)) provided for bonding.

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

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

(In the formula, R ² and R ³ independently represent a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom, and A ² is an alkylene group or an alkylidene group having 1 to 5 carbon atoms and an 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).)

(In the formula, R ⁴ and R ⁵ each independently represent a hydrogen atom, an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom, and A ³ is an alkylene group having 1 to 5 carbon atoms and an isopropylidene group. It is an ether group, a sulfide group, a sulfonyl group, a carbooxy group, a ketone group or a single bond.)

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

(In the formula, R ⁶ and R ⁷ each independently represent 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} the general formula ( ² ), R ² and R ^{3 in} the general formula ( ³ ), R ⁴ and R ⁵ in the general formula (3-1), R ⁶ and R ^{7 in the} general formula (5). Examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms shown by are methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-pentyl group and the like. Can be 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 (b2) (hereinafter, also referred to as “component (b2)”) is not particularly limited as long as it is a compound having two amino groups.

Examples of the component (b2) include 4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 4,4. '-Diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylketone, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4 '-Diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzene, 2,2-bis (3-amino-4-hydroxyphenyl) propane, 3,3'- Didimethyl-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) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 9,9- Examples thereof include bis (4-aminophenyl) fluorene. One of these may be used alone, or two or more thereof may be used in combination.
Among these, 4,4'-diaminodiphenylmethane and 4,4'-diamino-3,3'are highly soluble in organic solvents, have a high reaction rate during synthesis, and can have high heat resistance. -Dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 4,4'-[1,3-phenylene bis ( 1-Methylethylidene)] bisaniline, 4,4'-[1,4-phenylenebis (1-methylethylidene)] bisaniline is preferable, and 3,3'-is excellent in dielectric properties and low water absorption. Didimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide is preferable, and 2,2-bis [4] is excellent in mechanical properties such as high adhesion to a conductor, elongation of a cured product, and breaking strength. -(4-Maleimide phenoxy) phenyl] propane is preferred. Further, in addition to the above-mentioned excellent solubility, reaction rate, heat resistance, and high adhesiveness to a conductor, excellent high-frequency characteristics and low hygroscopicity can be exhibited, which is 4,4'-[1,3. -Phenylene bis (1-methylethylidene)] bisaniline and 4,4'-[1,4-phenylene bis (1-methylethylidene)] bisaniline are more preferred.

Examples of the structural unit derived from the component (b2) 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 formula (6-1) and (6-2), ^{A 4} represents a residue of component (b2), * represents a bonding unit.

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

(In the formula, 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 has a carbon number of carbon atoms. 1 to 5 alkylene group or alkylidene group, ether group, sulfide group, sulfonyl group, carbooxy group, ketone group, fluorenylene group, single bond, represented by the following general formula (7-1) or the following general formula (7-2) Is the group to be

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

(In the formula, 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 and an isopropylidene group. It is an ether group, a sulfide group, a sulfonyl group, a carbooxy group, a ketone group or a single bond.)

Aliphatic hydrocarbons having 1 to 5 carbon atoms represented by R ⁸ and R ^{9 in} the general formula (7), R ¹⁰ and R ^{11 in} the general formula (7-1), and R ¹² in the general formula (7-2). The hydrogen group is described in the same manner as the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ¹ in the general formula (2).
The alkylene groups having 1 to 5 carbon atoms represented by A ^{5 in} the general formula (7), A ^{6 in} the general formula (7-1), and A ⁷ and A ⁸ in the general formula (7-2) are described above. It will be described 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 thermosetting resin (B) is a polyaminobismaleimide compound represented by the following general formula (8) in terms of solubility in an organic solvent, high frequency characteristics, high adhesiveness to a conductor, moldability of a film, and the like. It is preferable to contain it.

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

The polyimide compound (B1) can be produced, for example, by reacting the component (b1) with the component (b2).
The reaction between the component (b1) and the component (b2) is preferably carried out in an organic solvent. The organic solvent is not particularly limited, and for example, 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, Aromatic hydrocarbons such as xylene and mesitylen; esters such as methoxyethyl acetate, ethoxyethyl acetate, butoxyethyl acetate and ethyl acetate; N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2- Examples thereof include nitrogen-containing substances such as pyrrolidone. One of these may be used alone, or two or more thereof may be used in combination. Among these organic solvents, methyl ethyl ketone, cyclohexanone, propylene glycol monomethyl ether, N, N-dimethylformamide, and N, N-dimethylacetamide are preferable from the viewpoint of solubility.

The equivalent ratio (Ta2 / Ta1) of the maleimide group equivalent (Ta1) of the component (b1) to the -NH ₂ group equivalent (Ta2) of the component (b2) in producing the polyimide compound (B1) is 0.05 to 1.0 is preferable, 0.1 to 0.8 is more preferable. By reacting the component (b1) and the component (b2) within the above range, good high frequency characteristics, heat resistance, flame retardancy and glass transition temperature can be obtained in the thermosetting resin composition of the present embodiment. ..

When the component (b1) and the component (b2) are reacted, a reaction catalyst can be used if necessary. The reaction catalyst is not particularly limited, but for example, an acidic catalyst such as p-toluenesulfonic acid; amines such as triethylamine, pyridine and tributylamine; imidazoles such as methylimidazole and phenylimidazole; triphenylphosphine. Such as phosphorus-based catalysts. One of these may be used alone, or two or more thereof may be used in combination. When the reaction catalyst is used, the amount used is not particularly limited, but for example, it can be used in the range of 0.01 to 5.0% by mass with respect to the component (b1) and the component (b2).

A polyimide compound (B1) can be obtained by charging a predetermined amount of a component (b1), a component (b2), an organic solvent and, if necessary, a reaction catalyst and the like into a synthesis kettle and causing a Michael addition reaction. The reaction conditions in this step are not particularly limited, but for example, the reaction temperature should be in the range of 50 to 160 ° C. and the reaction time should be in the range of 1 to 10 hours for workability such as reaction rate and gelation. It is preferable from the viewpoint of suppression and the like.
Further, in this step, the above-mentioned organic solvent can be added or concentrated to adjust the solid content concentration and solution viscosity of the reaction raw material. The solid content concentration of the reaction raw material is not particularly limited, but is preferably, for example, 10 to 90% by mass, and more preferably 20 to 80% by mass. 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, stirring efficiency is good, and gelation is less likely to occur.

After the production of the polyimide compound (B1), a part or all of the organic solvent may be removed and concentrated according to the purpose, or the organic solvent can be added and diluted. As the organic solvent additionally used, the organic solvent exemplified in the manufacturing process of the thermosetting resin (B) can be applied. One of these may be used alone, or two or more thereof may be used in combination. 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 weight average molecular weight of the polyimide compound (B1) is not particularly limited, but is preferably 500 to 6,000, more preferably 1,000 to 5,000, and further 1,500 to 4,000, for example. preferable. The measuring method described in Examples can be applied to the weight average molecular weight of the polyimide compound (B1).

The content of the thermosetting resin (B) in the thermosetting resin composition of the present embodiment is 20 to 95 mass in the total mass of all the resin components contained in the thermosetting resin composition of the present embodiment. % Is preferable, 40 to 90% by mass is more preferable, and 65 to 85% by mass is further preferable.

<Elastomer (C)>
The elastomer (C) is not particularly limited, and examples thereof include polybutadiene-based elastomers, styrene-based elastomers, olefin-based elastomers, urethane-based elastomers, polyester-based elastomers, polyamide-based elastomers, acrylic-based elastomers, and silicone-based elastomers. Examples include derivatives. One of these can be used alone, and two or more of them can be used in combination.

As the elastomer (C), one having a reactive functional group at the molecular terminal or in the molecular chain can be used. The reactive functional group may be, for example, one or more selected from the group consisting of maleic anhydride group, epoxy group, hydroxyl group, carboxy group, amino group, amide group, isocyanato group, acrylic group, methacryl group and vinyl group. It is more preferable that there 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 adhesion to a metal foil. From the viewpoint of dielectric properties, a maleic anhydride group is more preferable. By having these reactive functional groups, the compatibility with the resin is improved, and the separation between the inorganic filler (A) and the resin component when the interlayer insulating layer is formed tends to be suppressed. From the same viewpoint, the elastomer (C) is preferably an elastomer modified with maleic anhydride.

Preferable examples of the polybutadiene-based elastomer include those having a structure of a 1,4-trans form and a 1,4-cis form containing a 1,2-vinyl group.
As the polybutadiene-based elastomer, those having a reactive functional group are used from the viewpoint of improving the compatibility with the resin and suppressing the separation of the inorganic filler (A) and the resin component when the interlayer insulating layer is formed. Preferably, a polybutadiene-based elastomer modified with an acid anhydride is particularly preferable. The acid anhydride is not particularly limited, and for example, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, nagicic anhydride, Phthalic anhydride, dimethylglutaric anhydride, diethylglutaric anhydride, succinic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride and the like can be mentioned, and among these, maleic anhydride is preferable.
When the elastoma (C) 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 elastoma (C) is 1 to 10. Is preferable, 1 to 6 are more preferable, and 2 to 5 are even more preferable. When the number of acid anhydride groups is 1 or more in one molecule, the separation between the inorganic filler (A) and the resin component when the interlayer insulating layer is formed tends to be further suppressed. Further, when the number of acid anhydride groups is 10 or less in one molecule, the dielectric loss tangent of the thermosetting resin composition tends to be lower. When the elastomer (C) is modified with maleic anhydride, a group derived from maleic anhydride contained in one molecule of the elastomer (C) (hereinafter, also referred to as "maleic anhydride group") from the same viewpoint as above. The number of is preferably 1 to 10, more preferably 1 to 6, and even more preferably 2 to 5.
Polybutadiene-based elastomers are available as commercial products, and specific examples thereof include, for example, "POLYVEST (registered trademark) MA75", "POLYVEST (registered trademark) EP MA120" (all manufactured by Ebonic, trade name). Examples thereof include "Ricon (registered trademark) 130MA8", "Ricon (registered trademark) 131MA5", and "Ricon (registered trademark) 184MA6" (all manufactured by Clay Valley, trade name).

Preferable examples of the styrene-based elastoma include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, and styrene-ethylene-propylene-styrene block copolymer. Examples of the components constituting the styrene-based elastomer include styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene, in addition to styrene. Styrene-based elastoma is available as a commercial product, and specific examples thereof include "Toughprene (registered trademark)", "Asaprene (registered trademark) T", "Toughtech (registered trademark) H", and "Toughtech (registered trademark)". ) MP10 ”,“ Tough Tech (registered trademark) M1911 ”,“ Tough Tech (registered trademark) M1913 ”(above, manufactured by Asahi Kasei Chemicals Co., Ltd.),“ Epofriend (registered trademark) AT501 ”,“ Epofriend (registered trademark) CT310 ” (The above is manufactured by Daicel Co., Ltd.) and the like.

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

The urethane-based elastomer preferably contains, for example, 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 high molecular weight (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene-1,4-butylene adipate), polycaprolactone, and poly (1,6-he). 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-based elastomers are available as commercial products, and specific examples thereof include "PANDEX (registered trademark) T-2185" and "PANDEX (registered trademark) T-2983N" (all manufactured by DIC Corporation). Can be mentioned.

Examples of the polyester-based elastomer include those obtained by polycondensing 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 the hydrogen atom of these aromatic nuclei is 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. One of these compounds may be used alone, or two or more of these compounds may be used in combination.
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. Aliphatic diols such as bisphenol A, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3-methylphenyl) propane, aromatic diols such as resorcin and the like. One of these compounds can be used alone, and two or more of these compounds can be used in combination.

Further, as the polyester-based 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. There are various grades of multi-block copolymers depending on the types, ratios, and molecular weights of hard segments and soft segments. Specific examples thereof include "Hitrel (registered trademark)" (Dupont Toray Industries, Inc.), "Perprene (registered trademark)" (Toyo Spinning Co., Ltd.), and "Esper (registered trademark)" (Hitachi Kasei Co., Ltd.). ) Etc. can be mentioned.

As the polyamide-based elastoma, for example, polyamide is a hard segment component, polybutadiene, butadiene-acrylonitrile copolymer, styrene-butadiene copolymer, polyisoprene, ethylene propylene copolymer, polyether, polyester, polybutadiene, polycarbonate, polyacrylate. , Polymethacrylate, polyurethane, silicone rubber and the like as soft segment components.
Polyamide-based elastoma is available as a commercial product, and specific examples thereof include "UBE Polyamide Elastoma" (manufactured by Ube Industries, Ltd.), "Diamid (registered trademark)" (manufactured by Dicelle Evonik Corporation), and "PEBAX". (Registered trademark) "(Toray Industries, Inc.)," Grillon (registered trademark) ELY "(Ms. Chemie Japan Co., Ltd.)," Novamid (registered trademark) "(Mitsubishi Chemical Co., Ltd.)," Grelak (registered trademark) ) ”(Made by DIC Corporation),“ KAYAFLEX BPAM-01 ”,“ KAYAFLEX BPAM-155 ”(all manufactured by Nippon Kayaku Co., Ltd.) and the like.

Examples of the acrylic elastomer include a polymer of a raw material monomer containing an acrylic ester as a main component. Preferable examples of the acrylate ester include ethyl acrylate, butyl acrylate, methoxyethyl acrylate, and ethoxyethyl acrylate. Further, as the cross-linking point monomer, glycidyl methacrylate, allyl glycidyl ether and the like may be copolymerized, and further, acrylonitrile, ethylene and the like may be copolymerized. Specific examples thereof include an acrylonitrile-butyl acrylate copolymer, an acrylonitrile-butyl acrylate-ethyl acrylate copolymer, and an acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer.

The silicone-based elastomer is an elastomer containing an organopolysiloxane as a main component, and is classified into, for example, polydimethylsiloxane-based, polymethylphenylsiloxane-based, polydiphenylsiloxane-based, and the like. Silicone-based elastomers are available as commercial products, and specific examples thereof include "X-22-163B", "X-22-163C", "X-22-1821", and "X-22-162C". (Shin-Etsu Chemical Co., Ltd.), Core-shell type silicone rubber "SY series" (Asahi Kasei Wacker Silicone Co., Ltd.), "SE series", "CY series", "SH series" (above, Toray Dow Corning Co., Ltd.) (Made by company), etc.

Among these elastomers, styrene-based elastomers, polybutadiene-based elastomers, olefin-based elastomers, polyamide-based elastomers, and silicone-based elastomers are preferable from the viewpoint of heat resistance and insulation reliability, and polybutadiene-based elastomers and styrene-based elastomers are preferable from the viewpoint of dielectric properties. Elastomers are more preferred.

The weight average molecular weight of the elastomer (C) is preferably 500 to 50,000, more preferably 1,000 to 30,000. When the weight average molecular weight of the elastomer (C) is 500 or more, the curability of the obtained thermosetting resin composition and the dielectric properties of the cured product tend to be better. Further, when the weight average molecular weight of the elastomer (C) is 50,000 or less, the separation of the inorganic filler (A) and the resin component when the obtained interlayer insulating layer is formed tends to be suppressed. As the weight average molecular weight of the elastomer (C), the method for measuring the weight average molecular weight of the polyimide compound (B1) described in Examples can be applied.

The content of the elastomer (C) is not particularly limited, but is preferably 1 to 70% by mass, preferably 5 to 50% by mass, based on the total mass of all the resin components contained in the thermosetting resin composition of the present embodiment. More preferably, 10 to 30% by mass is further preferable. By setting the content of the elastomer (C) within the above range, the dielectric loss tangent is low, the handleability when formed into a film is excellent, and the resin separation of the obtained interlayer insulating layer tends not to occur.

The total content of the thermosetting resin (B) and the elastomer (C) in the thermosetting resin composition of the present embodiment is not particularly limited, but all contained in the thermosetting resin composition of the present embodiment. Of the total mass of the resin components, 50% by mass or more is preferable, 60% by mass or more is more preferable, and 70% by mass or more is further preferable. The upper limit of the content is not particularly limited and may be 100%.

<Minimum melt viscosity>
The minimum melt viscosity of the thermosetting resin composition of the present embodiment is 300 to 1500 Pa · s from the viewpoint that the thermosetting resin composition melts and solidifies in the step of laminating press and adheres appropriately. It is preferably 400 to 1000 Pa · s, and more preferably 400 to 1000 Pa · s.

<Flame retardants, curing accelerators, etc.>
The thermosetting resin composition of the present embodiment may contain a flame retardant, a curing accelerator, or the like, if necessary.
By incorporating a flame retardant into the thermosetting resin composition of the present embodiment, better flame retardancy can be imparted. The flame retardant is not particularly limited, and examples thereof include chlorine-based flame retardants, bromine-based flame retardants, phosphorus-based flame retardants, and metal hydrate-based flame retardants. From the viewpoint of environmental compatibility, phosphorus-based flame retardants or metal hydrate-based flame retardants are preferable.
By incorporating an appropriate curing accelerator into the thermosetting resin composition of the present embodiment, the curability of the thermosetting resin composition is improved, and the dielectric properties, heat resistance, and high elastic modulus of the interlayer insulating layer are improved. The 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; and various phosphorus compounds such as triphenylphosphine.
In addition, the thermosetting resin composition of the present embodiment may contain additives such as an antioxidant and a flow conditioner.

[Resin film for interlayer insulation]
The interlayer insulating resin film of the present embodiment contains the thermosetting resin composition of the present embodiment.
The interlayer insulating resin film of the present embodiment may have a support provided on one of the surfaces thereof.
Examples of the support include a polyolefin film such as polyethylene, polypropylene, and polyvinyl chloride; a polyester film such as polyethylene terephthalate (hereinafter, also referred to as “PET”) and polyethylene naphthalate; various plastics such as a polycarbonate film and a polyimide film. Examples include film. Further, a metal foil such as copper foil or aluminum foil, a paper pattern, or the like may be used. The support and the protective film described later may be subjected to surface treatment such as matte treatment and corona treatment. Further, the support and the protective film described later may be subjected to a mold release treatment with a silicone resin-based mold release agent, an alkyd resin-based mold release agent, a fluororesin-based mold release agent, or the like.

The thickness of the support is not particularly limited, but is preferably 10 to 150 μm, more preferably 25 to 50 μm.

The use of the interlayer insulating resin film of the present embodiment is not particularly limited, but is limited to adhesive films, insulating resin sheets such as prepregs, circuit boards, solder resists, underfill materials, die bonding materials, semiconductor encapsulants, hole filling resins, etc. It can be used in a wide range of applications where an interlayer insulating layer such as a component-embedded resin is required. Above all, it can be suitably used for forming an interlayer insulating layer in the production of a printed wiring board.

Next, a method for producing the interlayer insulating resin film of the present embodiment will be described.
<Manufacturing method of resin film for interlayer insulation>
The interlayer insulating resin film of the present embodiment can be produced, for example, as follows.
When producing a resin film for interlayer insulation, first, the inorganic filler (A), the thermosetting resin (B) and the elastomer (C) and other components used as necessary are dissolved or dissolved in an organic solvent. It is preferable to disperse the varnish into a resin varnish (hereinafter, also referred to as "varnish for resin film for interlayer insulation").

Examples of the organic solvent used for producing the varnish for the resin film for interlayer insulation include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; and acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate and carbitol acetate. (Di) ethylene glycol monoalkyl ether or propylene glycol monoalkyl ether such as cellosolve, butyl carbitol, propylene glycol monomethyl ether; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methylpyrrolidone and the like. Examples thereof include amide-based solvents. These organic solvents may be used alone or in combination of two or more.
The blending amount of the organic solvent is preferably 10 to 60% by mass, more preferably 10 to 35% by mass, based on the total mass of the varnish for the resin film for interlayer insulation.

The interlayer insulating resin film varnish thus produced is applied to the support and then heated and dried to obtain an interlayer insulating resin film.
As a method of applying the varnish for the resin film for interlayer insulation to the support, for example, a coating device such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, or a die coater can be used. It is preferable that these coating devices are appropriately selected depending on the film thickness.
The drying conditions after coating are not particularly limited. For example, in the case of a varnish for a resin film for interlayer insulation containing an organic solvent of 30 to 60% by mass, the layers are dried at 50 to 150 ° C. for about 2 to 10 minutes. An insulating resin film can be suitably formed. It is preferable to dry the resin film for interlayer insulation after drying so that the content of the volatile component (mainly an organic solvent) is 10% by mass or less, and more preferably to 6% by mass or less. preferable.

When the resin film for interlayer insulation of the present embodiment is used by arranging it on the conductor layer, it is preferably equal to or more than the thickness of the conductor layer of the circuit board from the viewpoint of embedding the conductor layer of the circuit board. Specifically, since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70 μm, the thickness of the resin film for interlayer insulation is preferably 5 to 100 μm.

A protective film may be provided on the surface of the interlayer insulating resin film formed on the support on the side opposite to the support. The thickness of the protective film is not particularly limited, but is, for example, 1 to 40 μm. By laminating the protective film, it is possible to prevent dust and the like from adhering to the surface of the interlayer insulating resin film and scratches. The interlayer insulating resin film can be rolled up and stored.

[Composite film]
The composite film of the present embodiment may be a composite film containing a first resin layer containing the thermosetting resin composition of the present embodiment and a second resin layer.

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

<First resin layer>
The first resin layer 1 contains the thermosetting resin composition of the present embodiment. The first resin layer 1 is provided between the circuit board and the adhesion auxiliary layer in the case of manufacturing a multilayer printed wiring board using the composite film of the present embodiment, for example, and is provided on the conductor layer of the circuit board and above it. It is used to insulate the layer of. Further, when the circuit board has through holes, via holes, etc., the first resin layer 1 flows into them and also plays a role of filling the holes.

<Second resin layer>
The second resin layer 2 is located between the cured product of the first resin layer containing the thermosetting resin composition of the present embodiment and the conductor layer in the printed wiring board of the present embodiment described later. It is provided for the purpose of improving the adhesiveness with the conductor layer. By providing the second resin layer, a smooth surface can be obtained, and better adhesive strength can be obtained with the conductor layer formed by plating. Therefore, from the viewpoint of forming fine wiring, it is preferable to provide the second resin layer 2.

The second resin layer 2 is not particularly limited as long as it improves the adhesiveness with the conductor layer, but for example, even if the surface roughness is small, the adhesiveness with the plated copper is excellent and the dielectric positive contact is good. From the viewpoint of obtaining a low interlayer insulating layer, a polyfunctional epoxy resin (D), an active ester curing agent (E), and a phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (F) (hereinafter, also referred to as “component (F)”) are used. It preferably contains a second thermosetting resin composition.

<Multifunctional epoxy resin (D)>
The polyfunctional epoxy resin (D) is not particularly limited as long as it is a resin having two or more epoxy groups, and is, for example, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, and a 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, aralkylnovolac type epoxy resin, fluorene type epoxy resin, xantene type epoxy resin And so on. From the viewpoint of adhesiveness to 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.

As the polyfunctional epoxy resin (D), a commercially available product may be used. Commercially available polyfunctional epoxy resins (D) include "NC-3000-H", "NC-3000-L", and "NC" manufactured by Nippon Kayaku Co., Ltd., which are aralkyl novolac type epoxy resins having a biphenyl structure. -3100 ”,“ NC-3000 ”and the like.
As the polyfunctional epoxy resin (D), one type may be used alone, or two or more types may be used in combination.

The epoxy equivalent of the polyfunctional epoxy resin (D) is not particularly limited, but is preferably 150 to 450 g / mol, more preferably 200 to 400 g / mol, and even more preferably 250 to 350 g / mol from the viewpoint of adhesiveness.

The content of the polyfunctional epoxy resin (D) in the second thermosetting resin composition is not particularly limited, but is 10 to 10 in the total mass of all the resin components contained in the second thermosetting resin composition. 90% by mass is preferable, 20 to 80% by mass is more preferable, and 30 to 70% by mass is further preferable. When the content of the polyfunctional epoxy resin (D) is 10% by mass or more, better adhesive strength with plated copper is obtained, and when it is 90% by mass or less, lower dielectric loss tangent tends to be obtained. is there.

<Active ester curing agent (E)>
The active ester curing agent (E) has one or more ester groups in one molecule and has a curing action of an epoxy resin.
The active ester curing agent (E) is not particularly limited, and examples thereof include an ester compound obtained from an aliphatic or aromatic carboxylic acid and an aliphatic or aromatic hydroxy compound.
Among these, ester compounds obtained from aliphatic carboxylic acids, aliphatic hydroxy compounds and the like tend to be soluble in organic solvents and highly compatible with epoxy resins by containing aliphatic chains.
Further, ester compounds obtained from aromatic carboxylic acids, aromatic hydroxy compounds and the like tend to have higher heat resistance by having an aromatic ring.

Examples of the active ester curing agent (E) include phenol ester compounds, thiophenol ester compounds, N-hydroxyamine ester compounds, esterified compounds of heterocyclic hydroxy compounds, and the like.
More specifically, for example, an aromatic ester 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, and diphenylsulfonic acid can be mentioned. An aromatic carboxylic acid component selected from those in which 2 to 4 hydrogen atoms in the ring are substituted with a carboxy group, 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 between an aromatic carboxylic acid and a phenolic hydroxyl group are preferable, using a mixture of 2 to 4 of the above with a polyvalent phenol substituted with a hydroxyl group as a raw material. 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.

As the active ester curing agent (E), a commercially available product may be used. Commercially available products of the active ester curing agent (E) include, for example, "EXB9451", "EXB9460", "EXB9460S", and "HPC-8000-65T" (DIC) as active ester compounds containing a dicyclopentadiene type diphenol structure. (Manufactured by Co., Ltd.), "EXB9416-70BK" (manufactured by DIC Co., Ltd.) as an active ester compound containing a naphthalene structure, "DC808" (manufactured by Mitsubishi Chemical Co., Ltd.) as an active ester compound containing an acetylated product of phenol novolac, Examples of the active ester compound containing a benzoyl compound include "YLH1026" (manufactured by Mitsubishi Chemical Corporation).
As the active ester curing agent (E), one type may be used alone, or two or more types may be used in combination.

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

The equivalent ratio (ester group / epoxy group) of the ester group of the active ester curing agent (E) to the epoxy group of the polyfunctional epoxy resin (D) in the second thermosetting resin composition is 0.05 to 1.5 is preferable, 0.1 to 1.3 is more preferable, and 0.2 to 1.0 is further preferable. When the equivalent ratio (ester group / epoxy group) is within the above range, the adhesive strength with the plated copper is further increased, and a lower dielectric loss tangent and a smooth surface can be obtained, which is preferable from the viewpoint of forming fine wiring. is there.

<Phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (F)>
The component (F) is not particularly limited as long as it is a polybutadiene-modified polyamide resin having a phenolic hydroxyl group, but is a diamine-derived structural unit, a dicarboxylic acid-derived structural unit containing a phenolic hydroxyl group, and a phenolic hydroxyl group. It is preferable to have a structural unit derived from dicarboxylic acid that does not contain the above and a structural unit derived from polybutadiene having a carboxy group at both ends. Specifically, 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) are preferably mentioned. Be done.

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. ~ 30, y + z = 2 to 300 ((y + z) / x) for x = 1, and z ≧ 20 (z / y) for y = 1.
In the general formulas (i) to (iii), R'independently represents a divalent group derived from an aromatic diamine or an aliphatic diamine, and in the general formula (iii), R'' is an aromatic dicarboxylic acid. , An aliphatic dicarboxylic acid or a divalent group derived from an oligomer having a carboxy group at both ends.
The plurality of R'included in the general formulas (i) to (iii) may be the same or different. Further, when z is an integer of 2 or more, a plurality of R''s may be the same or different.
In the general formulas (i) to (iii), R'is specifically a divalent group derived from an aromatic diamine or an aliphatic diamine described later, and R'' is an aromatic group described later. It is preferably a divalent group derived from a dicarboxylic acid, an aliphatic dicarboxylic acid or an oligomer having a carboxy group at both ends.

Examples of the diamine used for forming the structural unit derived from diamine in the component (F) include aromatic diamines and aliphatic diamines.

Examples of the aromatic diamine include diaminobenzene, diaminotoluene, diaminophenol, diaminodimethylbenzene, diaminomethicylene, diaminonitrobenzene, diaminodiazobenzene, diaminonaphthalene, diaminobiphenyl, diaminodimethoxybiphenyl, diaminodiphenyl ether, diaminodimethyldiphenyl ether, and methylenediamine. , Methylenebis (dimethylaniline), Methylenebis (methoxyaniline), Methylenebis (dimethoxyaniline), Methylenebis (ethylaniline), Methylenebis (diethylaniline), Methylenebis (ethoxyaniline), Methylenebis (diethoxyaniline), Isopropyridendianiline, Diamino Examples thereof include benzophenone, diaminodimethylbenzophenone, diaminoanthraquinone, diaminodiphenylthioether, diaminodimethyldiphenylthioether, diaminodiphenylsulfone, diaminodiphenylsulfoxide and diaminofluorene.

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

Examples of the dicarboxylic acid containing a phenolic hydroxyl group used for forming a structural unit derived from a dicarboxylic acid containing a phenolic hydroxyl group in the component (F) include hydroxyisophthalic acid, hydroxyphthalic acid, hydroxyterephthalic acid, and dihydroxy. Examples thereof include isophthalic acid and dihydroxyterephthalic acid.

Examples of the phenolic hydroxyl acid-free dicarboxylic acid used to form a structural unit derived from a dicarboxylic acid that does not contain a phenolic hydroxyl group in the component (F) include aromatic dicarboxylic acid and aliphatic dicarboxylic acid at both ends. Examples thereof include an oligomer having a carboxy group.
Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, biphenyldicarboxylic acid, methylenedibenzoic acid, thiodibenzoic acid, carbonyldibenzoic acid, sulfonylbenzoic acid, naphthalenedicarboxylic acid and the like.
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, and di (meth). ) Acryloyloxysuccinic acid, (meth) acryloyloxymalic acid, (meth) acrylamide succinic acid, (meth) acrylamide malic acid and the like can be mentioned.

The polybutadiene having carboxy groups at both ends used for forming a structural unit derived from polybutadiene having carboxy groups at both ends in the component (F) may have, for example, a number average molecular weight of 200 to 10,000. Preferably, it is an oligomer having a number average molecular weight of 500 to 5,000.

The weight average molecular weight of the component (F) is not particularly limited, but is preferably, for example, 60,000 to 250,000, and more preferably 80,000 to 200,000. The weight average molecular weight of the component (F) can be determined by the same method as the weight average molecular weight of the polyimide compound (B1).

The active hydroxyl group equivalent of the component (F) 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. More preferred.

The component (F) contains, for example, a diamine, a dicarboxylic acid containing a phenolic hydroxyl group, a dicarboxylic acid not containing a phenolic hydroxyl group, and polybutadiene having a carboxy group at both ends in an organic solvent such as dimethylacetamide. , It is synthesized by reacting a carboxylic acid ester as a catalyst in the presence of a pyridine derivative and polycondensing a carboxy group and an amino group. Examples of each compound that can be used in the production include those described above.

As the component (F), a commercially available product can be used, and examples of the component (F) of the commercially available product include "KAYAFLEX BPAM-155" manufactured by Nippon Kayaku Co., Ltd.

The content of the component (F) in the second thermosetting resin composition is not particularly limited, but is 1 to 20% by mass in the total mass of all the resin components contained in the second thermosetting resin composition. Is preferable, 2 to 15% by mass is more preferable, and 3 to 10% by mass is further preferable. When the content of the component (F) is 1% by mass or more, the toughness of the resin composition can be increased, a fine roughened shape can be obtained, and the adhesive strength with the plated copper can be increased. .. Further, when it is 20% by mass or less, the heat resistance does not decrease, and the decrease in resistance to the chemical solution during the roughening step can be prevented. In addition, sufficient adhesiveness with plated copper can be ensured.

<Phosphorus-based curing accelerator (G)>
The second thermosetting resin composition preferably further contains a phosphorus-based curing accelerator (G).
The phosphorus-based curing accelerator (G) is not particularly limited as long as it contains a phosphorus atom and promotes the reaction between the polyfunctional epoxy resin (D) and the active ester curing agent (E). Can be done.
By containing the phosphorus-based curing accelerator (G) in the second thermosetting resin composition, the curing reaction can be further sufficiently advanced. The reason for this is that by using the phosphorus-based curing accelerator (G), the electron-attracting property of the carbonyl group in the active ester curing agent (E) can be enhanced, which is more than that of the active ester curing agent (E). It is presumed that this is because the reaction with the functional epoxy resin (D) is promoted.
As described above, the second thermosetting resin composition contains the phosphorus-based curing accelerator (G), so that the polyfunctional epoxy resin (D) and the active ester are cured more than when other curing accelerators are used. Since the curing reaction with the agent (E) 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-based curing accelerator (G) include triphenylphosphine, diphenyl (alkylphenyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) phosphine, tris (alkylalkoxyphenyl) phosphine, and tris (dialkylphenyl). ) Hosphine, tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, dialkylarylphosphine , Organic phosphine such as alkyldiarylphosphine; complex of organic phosphine and organic borons; and adducts of tertiary phosphine and quinones. Adducts of tertiary phosphine and quinones are preferable from the viewpoint that the curing reaction proceeds more sufficiently and high adhesiveness to plated copper can be exhibited.

The third phosphine is not particularly limited, and is, for example, tri-n-butylphosphine, dibutylphenylphosphine, butyldiphenylphosphine, ethyldiphenylphosphine, triphenylphosphine, tris (4-methylphenyl) phosphine, tris (4-methoxy). Phosphine) phosphine and the like. Examples of quinones include o-benzoquinone, p-benzoquinone, diphenoquinone, 1,4-naphthoquinone, anthraquinone and the like. An adduct of tri-n-butylphosphine and p-benzoquinone is more preferable from the viewpoint of adhesiveness to plated copper, heat resistance, and a smooth surface.

As a method for producing an adduct of the third phosphine and quinones, for example, a method of stirring and mixing the three phosphine and quinones as raw materials in a solvent in which both of them are dissolved, subjecting them to an addition reaction, and then isolating them. And so on. In this case, for example, the tertiary phosphine and quinones are stirred in a solvent such as methyl isobutyl ketone, methyl ethyl ketone, and ketones such as acetone in the range of 20 to 80 ° C. for 1 to 12 hours. , It is preferable to carry out an addition reaction.

One type of phosphorus-based curing accelerator (G) may be used alone, or two or more types may be used in combination. Further, one or more kinds of curing accelerators other than the phosphorus-based curing accelerator (G) may be used in combination.

The content of the phosphorus-based curing accelerator (G) in the second thermosetting resin composition is not particularly limited, but is 0 in the total mass of all the resin components contained in the second thermosetting resin composition. .1 to 20% by mass is preferable, 0.2 to 15% by mass is more preferable, and 0.4 to 10% by mass is further preferable. When the content of the phosphorus-based curing accelerator (G) is 0.1% by mass or more, the curing reaction can be sufficiently advanced, and when it is 20% by mass or less, the homogeneity of the cured product can be maintained. ..

<Filler (H)>
The second thermosetting resin composition may contain a filler (H). Examples of the filler (H) include an inorganic filler and an organic filler.
By containing the filler (H), the scattering of the resin can be further reduced when the second resin layer is laser-processed.

The inorganic filler is not particularly limited, and for example, the same one as that exemplified as the inorganic filler (A) can be used.
The specific surface area of the inorganic filler is preferably 20 m ² / g or more, more preferably 50 m ² / g or more, from the viewpoint of forming fine wiring on the second resin layer. The upper limit of the specific surface area is not particularly limited, but from the viewpoint of availability, 500 m ² / g or less is preferable, and 200 m ² / g or less is more preferable.
The specific surface area can be determined by the BET method by low temperature and low humidity physical adsorption of an inert gas. Specifically, a molecule having a known adsorption area such as nitrogen is adsorbed on the surface of the powder particles at the temperature of liquid nitrogen, and the specific surface area of the powder particles can be obtained from the adsorption amount.

As the inorganic filler having a specific surface area of 20 m ² / g or more, a commercially available product may be used. Commercially available products include, for example, fumed silica "AEROSIL (registered trademark) R972" (manufactured by Nippon Aerosil Co., Ltd., trade name, specific surface area 110 ± 20 m ² / g) and "AEROSIL (registered trademark) R202" ( Nippon Aerosil Co., Ltd., trade name, specific surface area 100 ± 20 m ² / g), colloidal silica "PL-1" (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) and the like. Further, from the viewpoint of improving the moisture resistance, it is preferable that the inorganic filler is surface-treated with a surface treatment agent such as a silane coupling agent.

The content of the inorganic filler in the second thermosetting resin composition is preferably 1 to 30% by mass, more preferably 2 to 25% by mass, based on the solid content of the second thermosetting resin composition. 3 to 20% by mass is more preferable, and 5 to 20% by mass is particularly preferable. When the content of the inorganic filler is 1% by mass or more, better laser workability tends to be obtained, and when it is 30% by mass or less, the second resin layer and the conductor layer are further improved. There is a tendency.

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

<Other ingredients>
In addition to the above components, the second thermosetting resin composition includes other thermosetting resins, thermoplastic resins, flame retardants, and antioxidants as necessary, as long as the effects of the present invention are not impaired. , Additives such as flow conditioners and curing accelerators can be contained.

<Support>
In the composite film of the present embodiment, a support may be further provided on the surface of the second resin layer opposite to the first resin layer.
Examples of the support include the same supports that can be used for the interlayer insulating resin film of the present embodiment.

<Manufacturing method of composite film>
The composite film of the present embodiment can be produced, for example, by a method of forming a second resin layer on the support and forming a first resin layer on the second resin layer.
For the formation of the first resin layer, the above-mentioned varnish for a resin film for interlayer insulation (here, also referred to as “varnish for a first resin layer”) can be used.
In order to form the second resin layer, a resin varnish in which the second thermosetting resin composition is dissolved or dispersed in an organic solvent (hereinafter, also referred to as “varnish for the second resin layer”) may be formed. preferable.
The method for producing the varnish for the second resin layer and the organic solvent used for producing the varnish for the second resin layer are the same as those for the resin film varnish for interlayer insulation.
The blending amount of the organic solvent is preferably 70 to 95% by mass, more preferably 80 to 90% by mass, based on the total mass of the varnish for the second resin layer.

The varnish for the second resin layer produced in this manner is applied to the support and then heat-dried, and then the varnish for the first resin layer is further applied and then heat-dried. , Composite film can be formed.
The coating method of the varnish for the second resin layer or the varnish for the first resin layer and the drying conditions after coating the varnish are the coating method and the drying in the method for producing the resin film for interlayer insulation of the present embodiment. The conditions are the same.

The thickness of the first resin layer formed in the composite film of the present embodiment may be appropriately determined according to the required performance, but from the viewpoint of embedding the conductor layer of the circuit board, the thickness of the conductor layer of the circuit board. The above is preferable. Specifically, since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70 μm, the thickness of the first resin layer is preferably 10 to 100 μm. The thickness of the second resin layer is preferably 1 to 15 μm.

A protective film may be provided on the surface of the first resin layer on which the second resin layer is not provided. The thickness of the protective film is not particularly limited, but may be, for example, 1 to 40 μm. By providing the protective film, it is possible to prevent dust and the like from adhering to the surface of the first resin layer and scratches. The composite film can also be rolled up and stored.

In the composite film of the present embodiment, the dielectric loss tangent of the cured product at 5 GHz is preferably 0.010 or less, more preferably 0.008 or less, further preferably 0.006 or less, and 0. It is particularly preferable that it is 005 or less. The dielectric loss tangent of the cured product of the composite film of the present embodiment can be obtained by the method described in the examples.

[Printed wiring board and its manufacturing method]
The printed wiring board of the present embodiment includes a cured product of the resin film for interlayer insulation of the present embodiment or a cured product of the composite film of the present embodiment. In other words, the printed wiring board of the present embodiment has an interlayer insulating layer, and at least one of the interlayer insulating layers contains a cured product of the thermosetting resin composition of the present embodiment.
Hereinafter, a method of manufacturing a multilayer printed wiring board by laminating a resin film for interlayer insulation or a composite film of the present embodiment on a circuit board will be described.

The method for manufacturing a multilayer printed wiring board according to the present embodiment includes the following steps (1) to (5), and after the step (1), the step (2) or the step (3), the support is attached. It may be peeled off or removed.
Step (1): Laminating the interlayer insulating resin film or composite film of the present embodiment on one side or both sides of the circuit board Step (2): Heat-curing the interlayer insulating resin film or composite film to form an interlayer insulating layer. Step (3): Drilling a hole in the circuit board on which the interlayer insulating layer is formed Step (4): Roughening the surface of the interlayer insulating layer Step (5): Roughening the interlayer insulating layer The process of plating on the surface

<Process (1)>
The step (1) is a step of laminating the interlayer insulating resin film or composite film of the present embodiment on one side or both sides of the circuit board. Examples of the device for laminating the resin film for interlayer insulation or the composite film include a vacuum laminator. A commercially available product 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 pressurized laminator manufactured by Meiki Co., Ltd., and a vacuum pressurizing laminator manufactured by Hitachi Industries Co., Ltd. Roll type dry coater, vacuum laminator manufactured by Hitachi AIC Co., Ltd., etc.

In the lamination, when the interlayer insulating resin film or composite film has a protective film, after removing the protective film, the interlayer insulating resin film or composite film is pressed and / or heated on the circuit board. Crimping.
When a composite film is used, the first resin layer is arranged so as to face the surface of the circuit board on which the circuit is formed.
The conditions for laminating are that the resin film or composite film for interlayer insulation and the circuit board are preheated as necessary, the crimping temperature (lamination temperature) is 60 to 140 ° C., and the crimping pressure is 0.1 to 1.1 MPa (9. It may be laminated under a reduced pressure of 8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ) and an air pressure of 20 mmHg (26.7 hPa) or less. Further, the laminating method may be a batch method or a continuous method using a roll.

<Process (2)>
The step (2) is a step of thermosetting the interlayer insulating resin film or 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. The support may be peeled off after being thermoset.

<Process (3)>
The step (3) is a step of drilling holes in the circuit board on which the 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 a drill, a laser, a plasma, or a combination thereof to form via holes, through holes, and the like. As the laser, a carbon dioxide gas laser, a YAG laser, a UV laser, an excimer laser and the like are generally used.

<Process (4)>
The 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 they are formed. It is also possible to remove "smear".
The oxidizing agent is not particularly limited, and examples thereof include permanganate (potassium permanganate, sodium permanganate), dichromate, ozone, hydrogen peroxide, sulfuric acid, nitric acid and the like. Among these, alkaline permanganate solution (for example, potassium permanganate, sodium permanganate solution), which is an oxidizing agent commonly used for roughening the interlayer insulating layer in the production of a multilayer printed wiring board by the build-up method, is used. It may be used to roughen and remove smears.

<Process (5)>
The step (5) is a step of plating the surface of the roughened interlayer insulating layer. In this step, a semi-additive method in which a 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. Can be used. After forming the conductor layer, for example, by performing an annealing treatment at 150 to 200 ° C. for 20 to 120 minutes, the adhesive strength between the interlayer insulating layer and the conductor layer can be improved and stabilized.

Further, it may have a step of roughening the surface of the conductor layer thus produced. Roughening the surface of the conductor layer has the effect of enhancing the adhesiveness with the resin in contact with the conductor layer. The treatment agent for roughening the conductor layer is not particularly limited, but for example, "Mech Etch Bond (registered trademark) CZ-8100" and "Mech Etch Bond (registered trademark) CZ-" which are organic acid-based microetching agents. 8101 ”,“ MEC Etch Bond (registered trademark) CZ-5480 ”(all manufactured by MEC Co., Ltd., trade name) and the like can be mentioned.

The thermosetting resin composition, the resin film for interlayer insulation, the composite film, and the printed wiring board of the present embodiment can be particularly preferably used for electronic devices that handle high frequency signals of 1 GHz or higher, and particularly high frequency signals of 5 GHz or higher. It can be suitably used for electronic devices that handle high frequency signals of 10 GHz or higher or high frequency signals of 30 GHz or higher.

The present invention is not limited to the above embodiment. The above-described embodiment is an example, and any object having substantially the same configuration as the technical idea described in the claims of the present invention and exhibiting the same effect and effect is the present invention. Included in the technical scope.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples.

Manufacturing example 1
<Manufacturing of polyimide compound (B1)>
1,6-Bismaleimide- (2,2,4-trimethyl) hexane (Daiwa Kasei Kogyo Co., Ltd.) in a glass flask container with a volume of 1 liter that can be heated and cooled equipped with a thermometer, a reflux condenser, and a stirrer. Manufactured by, trade name: BMI-TMH) 385.377 g, 2,2-bis [4- (4-maleimide phenoxy) phenyl] propane (manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name: BMI-4000) 1611.619 g, 4 , 4'-[1,3-phenylenebis (1-methylethylidene)] bisaniline (manufactured by Mitsui Kagaku Fine Co., Ltd., trade name: bisaniline M) 278.004 g and propylene glycol monomethyl ether 3500 g were added, and the liquid temperature was 120 ° C. The reaction was carried out under stirring for 3 hours while refluxing with. Then, by gel permeation chromatography (GPC), it was confirmed that the weight average molecular weight of the reaction product was 3,000, and the polyimide compound (B1) (solid content concentration 65% by mass) was cooled and filtered by 200 mesh. Manufactured.

<Measurement method of weight average molecular weight>
The weight average molecular weight of the obtained polyimide compound (B1) was converted by GPC from a calibration curve using standard polystyrene. 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) was used to approximate with a cubic equation. The conditions for GPC are shown below.
Equipment: 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 Guardcolum HHR-L + Column; TSK gel-G4000HHR + TSK gel-G2000HHR (all manufactured by Tosoh Corporation, trade name)
Column size: 6.0 x 40 mm (guard column), 7.8 x 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

<Manufacturing method of varnish for first resin layer (varnish A)>
Silica (manufactured by Admatex Co., Ltd., methyl isobutyl ketone dispersion having a solid content concentration of 51% by mass, average particle size of 50 nm) treated with an aminosilane coupling agent as the nanofila (a) is used as an inorganic filler other than the nanofila (a). As (A), silica treated with an aminosilane coupling agent (manufactured by Admatex Co., Ltd., trade name: SC-2050-KNK, methyl isobutyl ketone dispersion having a solid content concentration of 70% by mass, average particle size of 0.5 μm) A polybutadiene-based elastoma (manufactured by Ebonic, trade name: POLYVEST 75MA) was used as the elastoma (C), and the content of the nanofiller (a) was 0 with respect to 100% by mass of the solid content contained in the resin composition. .4% by mass, the content of the inorganic filler (A) other than the nanofiller (a) is 76.9% by mass, and the content of the elastoma (C) is 76.9% by mass with respect to 100% by mass of the solid content contained in the resin composition. However, the mixture 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 (B) produced in Production Example 1 was mixed therewith at a ratio of the content of the polyimide compound (B) being 17% by mass with respect to 100% by mass of the solid content contained in the resin composition. It was melted at room temperature with a high-speed rotary mixer.
After visually confirming that the polyimide compound (B) was dissolved, 1,3-phenylenebis (di2,6-xylenyl phosphate) (manufactured by Daihachi Chemical Industry Co., Ltd., trade name: PX-) was used as a flame retardant. 200) was added to 1.0% by mass with respect to 100% by mass of the solid content contained in the resin composition, and 4,4'-butylidenebis- (6-t-butyl-3-methylphenol) (phenol) as an antioxidant. Antioxidant) (manufactured by Mitsubishi Chemical Industry Co., Ltd., trade name: Yoshinox (registered trademark) BB) (hereinafter, also referred to as “Yoshinox BB”) is 0 with respect to 100% by mass of the solid content contained in the resin composition. .1% by mass, "BYK310" (manufactured by Big Chemie Japan Co., Ltd., trade name, xylene solution having a solid content concentration of 25% by mass) as a flow conditioner was added to 100% by mass of the solid content contained in the resin composition. 0.1% by mass (solid content) was mixed. After that, as a curing accelerator, an organic peroxide (manufactured by Nichiyu Co., Ltd., trade name: Perbutyl P) is added as a raw material component (b1) converted from the amount of the polyimide compound (B1) charged and a polybutadiene-based elastomer (C). 1.0 phr, isocyanate mask imidazole (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: G8009L) was added to the total amount of the polyimide compound (B1), which was 0. 5 phr was mixed. Then, it was dispersed by nanomizer treatment to obtain varnish A.

Varnishes B to F were obtained in the same manner as varnish A except that each component and the blending amount thereof were changed to the blending shown in Table 1.

<Manufacturing method of varnish for second resin layer>
6.4% by mass of phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (manufactured by Nippon Kayaku Co., Ltd., trade name: KAYAFLEX BPAM-155) with respect to 100% by mass of the solid content contained in the resin composition. 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 have a mass ratio of 1.6%. After dissolution, Aralquilnovolak type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name: NC-3000-H, epoxy equivalent 289 g / mol) was added to 57.2 with respect to 100% by mass of the solid content contained in the resin composition. Mass%, inorganic filler (manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil (registered trademark) R972, specific surface area 110 ± 20 m ² / g) is 8.8 with respect to 100 mass% of solid content contained in the resin composition. Mass%, antioxidant (manufactured by API Corporation, trade name: Yoshinox (registered trademark) BB) is 0.4% by mass with respect to 100% by mass of the solid content contained in the resin composition, and phenoxy resin (Mitsubishi). Chemical Co., Ltd., trade name: YX7200, methyl ethyl ketone diluted product (35% by mass)) with respect to 100% by mass of solid content contained in the resin composition, 9.1% by mass in terms of solid content, active ester curing agent ( Made by DIC Co., Ltd., trade name: HPC-8000-65T (toluene diluted product (65% by mass)) is 14.6% by mass in terms of solid content with respect to 100% by mass of solid content contained in the resin composition. The adjusting agent (manufactured by Big Chemie Japan Co., Ltd., trade name: BYK-310 (same as that used when manufacturing Wanis A)) was added to 100% by mass of the solid content contained in the resin composition in terms of solid content. 1% by mass and 3.4% by mass of a phosphorus-based curing accelerator (addition of tri-n-butylphosphine and p-benzoquinone) were blended and dissolved with respect to 100% by 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. Then, the varnish was dispersed by nanomizer treatment to obtain a varnish for a second resin layer.

<Manufacturing of composite film>
Example 1
The second resin layer varnish obtained above is used on a release-treated support (PET film, manufactured by Toray Film Processing Co., Ltd., trade name: Therapy (registered trademark) SY (RX) (thickness 38 μm)). The film was applied using a comma coater so that the thickness after drying was 2.7 μm, and dried at 140 ° C. for 3 minutes to form a second resin layer on the support. Next, the varnish A for the first resin layer is applied onto the second resin layer using a comma coater so that the thickness of the first resin layer after drying is 27.3 μm, and 90 It was dried at ° C. for 2 minutes. Next, a polypropylene film having a thickness of 15 μm was attached to the surface of the first resin layer and wound into a roll to obtain a composite film 1 having a support and a protective film.

Examples 2-3, Comparative Example 1
Using the first resin layer varnishes B to D, composite films 2 to 4 were obtained in the same manner as in Example 1.

[Manufacturing of resin plate]
The resin plate used for the measurement of the dielectric loss tangent was prepared by the following procedure.
(I) The protective film was peeled off from the composite film having the support and the protective film obtained in Examples 1 to 3 and Comparative Example 1, and then dried at 120 ° C. for 3 minutes.
Next, a composite film having a support after drying is subjected to a copper foil (electric field copper foil, thickness) using a vacuum pressurizing laminator (manufactured by Meiki Co., Ltd., trade name: MVLP-500 / 600-II). The composite film and the copper foil were laminated on the glossy surface of 35 μm) so as to be in contact with each other to obtain a laminate (P) in which the copper foil, the composite film, and the support were laminated in this order. The above laminating was carried out by a method in which the pressure was reduced for 30 seconds to bleed air between the layers, the pressure was adjusted to 0.5 MPa, and then the pressure was pressed at 120 ° C. for 30 seconds at a crimping pressure of 0.5 MPa. Then, the support was peeled off from the laminated body (P).
(II) Next, a composite film having another support and a protective film was prepared, the protective film was peeled off, and then dried at 110 ° C. for 3 minutes.
(III) Next, the composite film (P) from which the support obtained in (I) above has been peeled off and the composite film having the support after drying obtained in (II) above are formed by the composite films. Laminating under the same conditions as in (I) above so as to abut, a laminated body (Q) in which a copper foil, a layer composed of two layers of composite films, and a support were laminated in this order was obtained. Then, the support was peeled off from the laminated body (Q).
(IV) Next, the laminated body (Q) obtained by peeling off the support obtained in (III) above and the composite film having the support after drying obtained by the same method as in (II) above are obtained. The composite films were laminated under the same conditions as in (I) above so that the composite films were in contact with each other to obtain a laminated body (R) in which a copper foil, a layer composed of three composite film layers, and a support were laminated in this order.
(V) A laminated body (Q) was prepared by the same method as in (I) to (III) above.
(VI) The support of 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 laminated with the laminate (Q). The composite films of the body (R) were bonded to each other, and press molding was performed at 190 ° C. for 60 minutes at a crimping pressure of 3.0 MPa using a vacuum press. The obtained resin plate with double-sided copper foil was cured at 190 ° C. for 2 hours, and then 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 test pieces with a width of 2 mm and a length of 70 mm, and a network analyzer (manufactured by Agilent Technologies, Inc., trade name: E8364B) and a 5 GHz compatible cavity resonator (manufactured by Kanto Electronics Applied 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. The lower the dielectric loss tangent, the better the dielectric properties.

[Evaluation method of film handleability]
The handleability of the composite film having the support and the protective film obtained in Examples 1 to 3 and Comparative Example 1 was evaluated by the method shown below.
(1) Evaluation by cutting with a cutter The presence or absence of powder falling when the composite film having the support and the protective film produced above was cut with a cutter was evaluated. The presence or absence of powder falling was visually confirmed, and those that did not fall were considered to be easy to handle.
(2) Evaluation by Bending The presence or absence of cracks in the film was evaluated when the protective film of the support and the composite film having the protective film produced above was peeled off and bent 180 ° from the support toward the resin-coated surface. .. The presence or absence of cracks in the film was visually confirmed, and those in which cracks did not occur were considered to have good handleability.
In the evaluations of (1) and (2) above, those with good handleability were designated as "A", and the others were designated as "B". The evaluation results are shown in Table 1.

[Measurement method of minimum melt viscosity]
The produced composite films were stacked so as to be 1.0 mm, and the minimum melt viscosity was measured using a sample punched to φ20 mm. The viscosity was measured using a rheometer (trade name: ARESG2, manufactured by TA Instruments Japan Co., Ltd.) at a heating rate of 5 ° C./min, a φ20 mm jig, and a frequency of 1.0 Hz. The minimum melt viscosity is the viscosity when the thermosetting resin composition is melted before the start of curing.

[Method of manufacturing substrate for surface roughness measurement]
A substrate for measuring surface roughness was prepared by the following procedure.
The composite film having the support and the protective film obtained in Examples 1 to 3 and Comparative Example 1 was cut into a size of 240 mm × 240 mm, and then the protective film was peeled off.
The first resin layer and the printed wiring board abut the composite film having the obtained support on a printed wiring board (manufactured by Hitachi Kasei Co., Ltd., trade name: E-700GR) that has been subjected to CZ treatment. Laminated as. For laminating, the pressure is reduced at 120 ° C. for 30 seconds to bleed air between the first resin layer and the printed wiring board, and then the pressure is set to 0.5 MPa, and then the pressure is set to 120 ° C. for 30 seconds, and the crimping pressure is 0.5 MPa. It was done by the method of pressing with.
Then, it cooled to room temperature, and the printed wiring board which arranged the composite film was obtained. Next, the printed wiring board on which the composite film was arranged was 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 190 as the second stage curing. Curing was performed in an explosion-proof dryer at ° C. for 40 minutes. After curing, the support was peeled off to obtain a printed wiring board on which an interlayer insulating layer was formed.

[Roughening method]
The printed wiring board obtained above was immersed in a swollen liquid (manufactured by Rohm and Haas Electronic Materials Co., Ltd., trade name: CIRCUPOSITMLB CONDITIONER 211) heated to 60 ° C. for 10 minutes. Next, it was immersed in a roughened solution heated to 80 ° C. (manufactured by Rohm and Haas Electronic Materials Co., Ltd., trade name: CIRCUPOSITMLB PROMOTER 213) for 10 minutes. Subsequently, it was neutralized by immersing it in a neutralizing solution heated to 45 ° C. (manufactured by Rohm and Haas Electronic Materials Co., Ltd., trade name: CIRCUPOSITMLB NEUTRALIZER MLB216) for 5 minutes. The surface of the interlayer insulating layer of the printed wiring board roughened in this way was used as a substrate for surface roughness measurement.

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

[Adhesive strength with plated copper (plating peel strength) manufacturing method]
In carrying out the evaluation of the adhesive strength with the plated copper and the evaluation of the reflow heat resistance, an evaluation substrate was prepared by the following procedure.
First, a printed wiring board with a composite film produced by the same method as described above was cut into a size of 40 mm × 60 mm and used as a test piece.
The test piece is roughened under the same conditions as the above-mentioned substrate for surface roughness measurement, and then with an alkaline cleaner at 60 ° C. (manufactured by Atotech Japan Co., Ltd., trade name: Cleaner Security Gant (registered trademark) 902) 5 It was treated for minutes and degreased and washed. After washing, it was treated with a predip solution at 23 ° C. (manufactured by Atotech Japan Co., Ltd., trade name: Predip Neogant (registered trademark) B) for 2 minutes. Then, it was treated with an activator solution at 40 ° C. (manufactured by Atotech Japan Co., Ltd., trade name: Activator Neogant (registered trademark) 834) for 5 minutes to attach a palladium catalyst. Next, it was treated with a reducing solution at 30 ° C. (manufactured by Atotech Japan Co., Ltd., trade name: Reducer Neogant (registered trademark) WA) for 5 minutes.
The test piece subjected to the above treatment was placed in a chemical copper solution (manufactured by Atotech Japan Co., Ltd., trade name: Basic Print Gantt (registered trademark) MSK-DK) to bring the plating thickness on the interlayer insulating layer to 0.5 μm. Electroless plating was performed until it became. After electroless plating, bake 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, the test piece subjected to the electroless plating treatment was further electroplated until the plating thickness on the interlayer insulating layer became 35 μm to form a copper layer as a conductor layer. After electroplating, it was heat-annealed at 190 ° C. for 120 minutes and cured to obtain a measurement substrate before the production of the adhesive strength measuring section.
By forming a resist having a width of 10 mm on the copper layer of the obtained measurement substrate and etching the copper layer with ammonium persulfate, a substrate for measuring the adhesive strength with plated copper having a copper layer having a width of 10 mm as an adhesive strength measuring part. Got

[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 part is peeled off at the interface between the copper layer and the interlayer insulating layer, grasped with a gripper, and used in a small desktop tester (manufactured by Shimadzu Corporation, trade name: EZTTest) in the vertical direction. The pulling speed was 50 mm / min, and the load when peeled off at room temperature was measured. The evaluation results are shown in Table 1.

[Evaluation method for wiring embedding and flatness]
The composite film having the support and the protective film obtained in Examples 1 to 3 and Comparative Example 1 was cut into a size of 240 mm × 240 mm, and then the protective film was peeled off.
A printed wiring board (manufactured by Hitachi Kasei Co., Ltd.) in which a copper wiring having a thickness of 18 μm and a width of 5 mm and a copper wiring having a thickness of 18 μm and a width of 100 μm are formed on the composite film having the obtained support. A first resin layer was laminated on the product name: E-700GR) so that the first resin layer and the printed wiring board were in contact with each other. Lamination was performed by vacuuming at 100 ° C. for 15 seconds as the first stage, then pressurizing at 0.5 MPa for 45 seconds, and further pressing at 120 ° C. for 60 seconds at a crimping pressure of 0.5 MPa as the second stage. Then, it cooled to room temperature, and the printed wiring board which arranged the composite film was obtained. 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 190 ° C. as the second-stage curing. The mixture was cured in an explosion-proof dryer for 40 minutes to obtain a printed wiring board on which an interlayer insulating layer was formed. Then, the support was peeled off to obtain a printed wiring board. By visually observing the copper wiring part of this printed wiring board, the one having good embedding property and flatness of the 5 mm wide copper wiring and the 100 μm wide copper wiring is “very good”, and the 5 mm wide copper wiring and the 100 μm wide copper wiring One of the copper wirings having good embedding property and flatness was designated as "good", and one having poor embedding property and flatness of both wirings was designated as "bad".

From Table 1, it can be seen that the film handleability of the composite film using the thermosetting resin composition of the present embodiment is excellent. Further, from Table 1, the printed wiring boards of Examples 1 to 3 using the thermosetting resin composition of the present embodiment have a small dielectric loss tangent, a low minimum melt viscosity, and good wiring embedding property and flatness. Is. Further, by providing the adhesive layer, it has an interlayer insulating layer having a smooth surface (low surface roughness (Ra)) and excellent adhesive strength with plated copper, which is suitable for forming fine wiring. It turns out that there is.

The thermosetting resin composition of the present invention has a low dielectric loss tangent and low thermal expansion, and the resin film and composite film for interlayer insulation using the thermosetting resin composition of the present invention have wire embedding property and flatness. Excellent for. Therefore, the thermosetting resin composition, the resin film for interlayer insulation, the composite film, and the printed wiring board of the present invention are electric products such as computers, mobile phones, digital cameras, and televisions; motorcycles, automobiles, trains, ships, etc. It is useful for vehicles such as aircraft.

1 1st resin layer 2 2nd resin layer 3 Support 4 Protective film

Claims (11)

Contains an inorganic filler (A) containing a nanofiller (a), a thermosetting resin (B) and an elastomer (C) .
The thermosetting resin (B) is a polyimide compound having a structural unit derived from a maleimide compound (b1) having at least two N-substituted maleimide groups and a structural unit derived from a diamine compound (b2). Sex resin composition. The thermosetting resin composition according to claim 1, wherein the content of the nanofiller (a) is 0.1 to 1.0% by mass with respect to the total amount of the inorganic filler (A). The thermosetting resin composition according to claim 1 or 2, wherein the elastomer (C) is a polybutadiene-based elastomer . A resin film for interlayer insulation, which comprises the thermosetting resin composition according to any one of claims 1 to 3. A composite film comprising a first resin layer containing the thermosetting resin composition according to any one of claims 1 to 3 and a second resin layer. The second resin layer contains a second thermosetting resin composition containing a polyfunctional epoxy resin (D), an active ester curing agent (E), and a phenolic hydroxyl group-containing polybutadiene-modified polyamide resin (F). The composite film according to claim 5. The equivalent ratio (ester group / epoxy group) of the ester group of the active ester curing agent (E) to the epoxy group of the polyfunctional epoxy resin (D) in the second thermosetting resin composition is 0.05. The composite film according to claim 6, which is ~ 1.5. The composite film according to claim 6 or 7, wherein the second thermosetting resin composition further contains a phosphorus-based curing accelerator (G). The composite film according to any one of claims 5 to 8, wherein the cured product has a 5 GHz dielectric loss tangent of 0.005 or less. A printed wiring board containing a cured product of the resin film for interlayer insulation according to claim 4 or a cured product of the composite film according to any one of claims 5 to 9. A method for producing a printed wiring board, comprising a step of laminating the resin film for interlayer insulation according to claim 4 or the composite film according to any one of claims 5 to 9 on one side or both sides of a base material.