JPWO2016088743A1 - Resin sheet and printed wiring board - Google Patents

Abstract

A resin sheet comprising a resin composition that can be used as an insulating layer in printed wiring board materials, has excellent adhesion between the insulating layer and a conductor layer formed on the surface thereof, and has a low coefficient of thermal expansion when fully cured. obtain. The resin sheet is a resin sheet including an outer layer that is any one kind selected from the group consisting of a polymer film, a metal foil, and a metal film, and an insulating layer laminated on the outer layer, the insulating sheet The layer is a resin sheet containing an epoxy compound (A), a cyanate ester compound (B), aminosilane-treated silica (C), and an acid-soluble inorganic filler (D).

Description

  The present invention relates to a resin sheet and a printed wiring board useful as a material for an insulating layer of a printed wiring board.

  In recent years, electronic devices are becoming smaller and higher performance. In multilayer printed wiring boards, in order to improve the mounting density of electronic components, miniaturization of conductor wiring is progressing, and the wiring forming technology is desired. As a method of forming high-density fine wiring on the insulating layer, an additive method in which a conductor layer is formed only by electroless plating, or a conductor layer is formed by electrolytic plating after forming a thin copper layer on the entire surface by electroless plating. Then, a semi-additive method for flash-etching a thin copper layer after that is known.

  It is desirable to reduce the roughness of the surface of the insulating layer as much as possible since the plating at the deep portion of the physical anchor cannot be removed in the subsequent flash etching process. On the other hand, since the roughness of the surface of the insulating layer is small, the adhesion strength between the conductor layer and the insulating layer tends to decrease. Therefore, there is a demand for an insulating layer resin composition having a high interface adhesion strength with a conductor layer even when the roughness of the insulating layer surface is small.

  In addition, studies have been actively conducted to reduce the thickness of laminated boards used in multilayer printed wiring boards by reducing the size and increasing the density of multilayer printed wiring boards. With the thinning of multilayer printed wiring boards, the insulating layer is also required to be thinned, and the study of resin sheets that do not contain glass cloth is required. On the other hand, since problems such as a decrease in mounting reliability and an increase in warpage of the multilayer printed wiring board occur, high adhesion and low thermal expansion are required for the resin composition as a material for the insulating layer.

  Various efforts have been made against this. For example, Patent Document 1 discloses an arithmetic average of the surface of an insulating layer after a wet roughening step by using a resin composition characterized by containing an epoxy resin, a curing agent, and an inorganic filler surface-treated with aminobis (alkoxysilane). A technique is described in which not only the roughness is low but also the root mean square roughness is small, and a plated conductor layer having a sufficient peel strength can be formed thereon.

  In Patent Document 2, the epoxy resin (A), the curing agent (B), and a silica component (C) in which silica particles are surface-treated with a silane coupling agent are roughened. A technique is described in which a fine rough surface can be formed on the cured body and the adhesive strength between the cured body and the metal layer can be increased.

  Patent Document 3 discloses a first inorganic filler surface-treated with a thermosetting resin, a curing agent, and a first silane coupling, and a second inorganic filler surface-treated with a second silane coupling agent. The resin composition containing the material can reduce the surface roughness of the cured product after roughening, and further increase the adhesive strength between the cured product and the metal layer when a metal layer is formed on the surface of the cured product. The technology that can do is described.

JP 2014-15606 A Japanese Patent No. 4686750 International Publication No. 2014/038534 Pamphlet

  However, in the method described in Patent Document 1, the surface roughness and the adhesion with the conductor layer formed by plating are not satisfactory.

  Also, the method described in Patent Document 2 is not satisfactory in terms of surface roughness and adhesion with a conductor layer formed by plating.

  Further, with respect to the method described in Patent Document 3, fine irregularities were not formed by changing the silane coupling agent, and the surface roughness and the adhesion with the conductor layer formed by plating were not satisfactory.

  The present invention has been made in view of the above problems, and when used for an insulating layer in a printed wiring board material, the object is excellent in adhesion between the insulating layer and the conductor layer formed on the surface thereof, It is to obtain a resin sheet having a low coefficient of thermal expansion when fully cured, and to provide a printed wiring board using the resin sheet.

As a result of earnest studies, the present inventors have selected a resin sheet comprising an outer layer that is one type selected from the group consisting of a polymer film, a metal foil, and a metal film, and an insulating layer laminated on the outer layer. The insulating layer is composed of a resin sheet containing an epoxy compound (A), a cyanate ester compound (B), an aminosilane-treated silica (C), and an acid-soluble inorganic filler (D). The inventors have found that the problem can be solved and have reached the present invention.
[1] A resin sheet comprising an outer layer that is any one selected from the group consisting of a polymer film, a metal foil, and a metal film, and an insulating layer laminated on the outer layer,
The resin sheet in which the insulating layer contains an epoxy compound (A), a cyanate ester compound (B), aminosilane-treated silica (C), and an acid-soluble inorganic filler (D).
[2] The resin sheet according to [1], wherein the content of the aminosilane-treated silica (C) in the insulating layer is 50 to 350 parts by mass with respect to 100 parts by mass of the resin solid content.
[3] The content of the acid-soluble inorganic filler (D) in the insulating layer is 20 to 150 parts by mass with respect to 100 parts by mass of the resin solid content, according to [1] or [2] Resin sheet.
[4] The resin sheet according to any one of [1] to [3], wherein the acid-soluble inorganic filler (D) is magnesium hydroxide or magnesium oxide.
[5] The resin sheet according to any one of [1] to [4], wherein the resin composition further contains a maleimide compound (E).
[6] The resin sheet according to any one of [1] to [5], wherein the polymer film is any one selected from the group consisting of polyester, polyimide, and polyamide.
[7] The insulating layer is obtained by applying a composition containing the components (A) to (D) on the outer layer, and drying and solidifying under heating or reduced pressure. [1] to [ [6] The resin sheet according to any one of [6].
[8] A printed wiring comprising the insulating layer according to any one of [1] to [7], which is laminated on a circuit board having a core base material and a conductor circuit formed on the core base material. Board.
[9] The printed wiring board according to [8], wherein the insulating layer is surface-treated and includes a conductor layer patterned on the surface.
[10] The printed wiring board according to [9], wherein the surface treatment is a desmear treatment including a roughening treatment with a swelling agent and an alkaline oxidizing agent and a neutralization treatment with an acidic reducing agent.
[11] The printed wiring board according to [9] or [10], wherein the conductor layer includes a conductor layer formed by a semi-additive method or a conductor layer formed by a subtractive method.
[12] The printed wiring board according to [9] or [10], wherein the conductor layer includes a conductor layer obtained by etching an outer layer made of the metal foil or metal film according to [1].

The sheet of the present invention exhibits at least one of the following effects (1) to (3), preferably all.
(1) Excellent adhesion between the insulating layer and the conductor layer formed on the surface thereof.
(2) The substrate surface roughness is small.
(3) It has a low coefficient of thermal expansion.

  One aspect of the present invention is a resin sheet including an outer layer that is one type selected from the group consisting of a polymer film, a metal foil, and a metal film, and an insulating layer laminated on the outer layer, The insulating layer is a resin sheet containing an epoxy compound (A), a cyanate ester compound (B), aminosilane-treated silica (C), and an acid-soluble inorganic filler (D).

  Hereinafter, the present invention will be described in detail. In the present invention, “X to Y” includes X and Y which are the end values. “X or Y” means either X or Y or both.

  In the present invention, a composition containing components (A) to (D) and other components described later as required is referred to as a “resin composition”. A layer provided on the outer layer and containing the resin composition and having no fluidity at room temperature is referred to as an “insulating layer”. As will be described later, the insulating layer may contain a solvent. Further, since the insulating layer is used by being bonded to another material, it needs to be curable. Specifically, the curable resin in the insulating layer is uncured or partially reacted but is curable. A fluid having fluidity that contains the resin composition and a solvent and can be applied to the outer layer at room temperature is referred to as “varnish”. Hereinafter, each component will be described.

[I-1. Epoxy compound (A)]
The epoxy compound (A) used in the present invention is an organic compound having at least one epoxy group. The number of epoxy groups per molecule of the epoxy compound (A) is 1 or more. The number of the epoxy groups is more preferably 2 or more.

  A conventionally well-known epoxy resin can be used for an epoxy compound (A). As for an epoxy compound (A), only 1 type may be used and 2 or more types may be used together.

  Examples of the epoxy compound (A) include a biphenyl aralkyl type epoxy compound (epoxy group-containing biphenyl aralkyl resin), a naphthalene type epoxy compound (an epoxy group-containing compound having a naphthalene skeleton: a naphthalene bifunctional epoxy compound), and a bisnaphthalene type epoxy. Compound (epoxy group-containing compound having bisnaphthalene skeleton: naphthalene tetrafunctional epoxy compound), aromatic hydrocarbon formaldehyde type epoxy compound (epoxy group-containing aromatic hydrocarbon formaldehyde resin), anthraquinone type epoxy compound (epoxy having anthraquinone skeleton) Group-containing compound), naphthol aralkyl type epoxy compound (epoxy group-containing naphthol aralkyl resin), zylock type epoxy compound (epoxy group-containing zylock resin), Phenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol A novolak type epoxy resin, trifunctional phenol type epoxy compound (epoxy group-containing compound having trifunctional phenol skeleton), tetrafunctional phenol type epoxy compound (tetrafunctional phenol skeleton Epoxy group-containing compound), biphenyl type epoxy resin (epoxy group-containing compound having biphenyl skeleton), aralkyl novolac type epoxy resin, triazine skeleton epoxy compound (triazine skeleton containing epoxy resin) alicyclic epoxy resin, polyol type epoxy resin, It is obtained by the reaction of epoxidized double bonds of double bond-containing compounds such as glycidylamine, glycidyl ester and butadiene, and reaction of hydroxyl group-containing silicone resins with epichlorohydrin. Compounds, and the like.

  In addition, as described in the above examples, in the present specification, an epoxy compound having a structure obtained by epoxidizing a certain resin or compound is given a description of “˜type epoxy compound” in the name of the resin or compound. May be expressed.

  Among these, as the epoxy compound (A), biphenylaralkyl type epoxy compound, naphthalene type epoxy compound, bisnaphthalene type epoxy compound, aromatic from the viewpoints of adhesion between the insulating layer and the plated conductor layer and flame retardancy Hydrocarbon formaldehyde epoxy compounds (preferred examples include aromatic hydrocarbon formaldehyde resins obtained by polymerizing aromatic hydrocarbons such as benzene, toluene and xylene with formaldehyde, and hydroxyl-containing aromatic carbonization such as phenol and xylenol. Compounds modified with hydrogen and further epoxidized with hydroxyl groups, compounds with epoxidized hydroxyl groups of aromatic hydrocarbon formaldehyde resins obtained by polymerizing hydroxyl-containing aromatic hydrocarbons such as phenol and xylenol with formaldehyde, etc. ), Anthraquinone type Epoxy compounds, naphthol aralkyl-type epoxy compounds, and xylok type epoxy compound is preferably one or more members selected from the group consisting of.

  The biphenyl aralkyl type epoxy compound is preferably a compound represented by the formula (1). By using this preferable biphenyl aralkyl type epoxy compound resin, the combustion resistance of the insulating layer can be improved.

（式中、Ｒ^１は各々独立に、水素原子又はメチル基を表す。ｎ^１は１以上の整数を示す。）

(In the formula, each R ¹ independently represents a hydrogen atom or a methyl group. N ¹ represents an integer of 1 or more.)

  Although content of the epoxy compound (A) in this invention is not specifically limited, From a heat resistant and sclerosing | hardenable viewpoint, 20-80 mass parts range is preferable with respect to 100 mass parts of resin solid content of an insulating layer, and 30-70. The range of parts by mass is particularly suitable. Here, the “resin solid content of the insulating layer” is a component excluding the solvent, the aminosilane-treated silica (C), and the acid-soluble inorganic filler (D) in the insulating layer. As will be described later, when the insulating layer is manufactured with varnish, the insulating layer may contain a solvent. In this case, the resin solid content in the insulating layer is a component excluding silica (C), the inorganic filler (D), and the solvent. Therefore, the resin solid content of 100 parts by mass is the sum of the components excluding the solvent when the aminosilane-treated silica (C) and the acid-soluble inorganic filler (D) in the insulating layer and the solvent are included. Is 100 parts by mass.

  As the epoxy compound (A), off-the-shelf products with various structures are commercially available, and they can be appropriately obtained and used. Moreover, you may manufacture an epoxy compound (A) using a well-known various manufacturing method. Examples of such a production method include a method of obtaining or synthesizing a hydroxyl group-containing compound having a desired skeleton, modifying the hydroxyl group by a known method, and epoxidizing (introducing an epoxy group).

[I-2. Cyanate ester compound (B)]
The cyanate ester compound (B) used in the present invention is not particularly limited as long as it is a compound having a cyanate group (cyanate ester group). Specifically, naphthol aralkyl type cyanate ester compound (cyanate group-containing naphthol aralkyl resin), aromatic hydrocarbon formaldehyde type cyanate ester compound (cyanate group-containing aromatic hydrocarbon formaldehyde resin), biphenyl aralkyl type cyanate ester compound (Cyanato group-containing biphenyl aralkyl resin), novolac-type cyanate ester compound (cyanato group-containing novolak resin), and the like.

  Since these cyanate ester compounds (B) impart excellent properties such as high chemical resistance, high glass transition temperature, and low thermal expansion in the insulating layer of the present invention, they are suitable as components of the resin composition of the present invention. Can be used for

  In addition, as described in the above examples, in this specification, a cyanate ester compound (B) having a structure obtained by cyanating (cyanate esterification) a certain resin or compound is referred to as the name of the resin or compound. It may be expressed with a description of “-type cyanate ester compound”.

  Among these, as the cyanate ester compound (B), a naphthol aralkyl type cyanide is provided from the viewpoint of providing the insulating layer of the present invention having excellent flame retardancy, high curability, and high glass transition temperature of the cured product. Acid ester compound, aromatic hydrocarbon formaldehyde type cyanate ester compound (preferably, aromatic hydrocarbon formaldehyde resin obtained by polymerizing aromatic hydrocarbon such as benzene, toluene, xylene and the like with formaldehyde, phenol, Hydroxyl group-containing aromatic hydrocarbon formaldehyde obtained by polymerizing hydroxyl group-containing aromatic hydrocarbons such as phenol and xylenol with formaldehyde modified with hydroxyl group-containing aromatic hydrocarbons such as xylenol and further hydroxylating the hydroxyl group Compounds in which the hydroxyl group of the resin is cyanated , And one or more members selected from the group consisting of biphenyl aralkyl type cyanate ester compounds are particularly preferred.

  As the naphthol aralkyl type cyanate compound, a compound represented by the formula (2) is preferable.

（式中、Ｒ^２は各々独立に水素原子又はメチル基を表し、中でも水素原子が好ましい。ｎ^２は１以上の整数を示す。）

(In the formula, each R ² independently represents a hydrogen atom or a methyl group, and among them, a hydrogen atom is preferable. N ² represents an integer of 1 or more.)

  As the novolac-type cyanate ester compound, a compound represented by formula (3) or formula (4) is preferable.

（式中、Ｒ^３は水素原子又はメチル基を表し、中でも水素原子が好ましい。ｎ^３は１以上の整数を示す。）

(In the formula, R ³ represents a hydrogen atom or a methyl group, and among them, a hydrogen atom is preferable. N ³ represents an integer of 1 or more.)

（式中、Ｒ^４は水素原子又はメチル基を表し、中でも水素原子が好ましい。ｎ^４は１以上の整数を示す。）

(In the formula, R ⁴ represents a hydrogen atom or a methyl group, and among them, a hydrogen atom is preferable. N ⁴ represents an integer of 1 or more.)

  The content of the cyanate ester compound (B) in the present invention is not particularly limited, but from the viewpoint of heat resistance and curability, a range of 20 to 40 parts by mass is preferable with respect to 100 parts by mass of the resin solid content of the insulating layer. A range of 25 to 35 parts by weight is particularly suitable.

  As the cyanate ester compound (B), off-the-shelf products having various structures are commercially available, and can be appropriately obtained and used. Moreover, you may manufacture a cyanate ester compound (B) using a well-known various manufacturing method. Examples of such production methods include a method of obtaining or synthesizing a hydroxyl group-containing compound having a desired skeleton, and modifying the hydroxyl group by a known method to form cyanate. Examples of the method for cyanating a hydroxyl group include the method described in Ian Hamerton, “Chemistry and Technology of Cyanate Ester Resins,” Blackie Academic & Professional.

[I-3. Aminosilane-treated silica (C)]
The aminosilane-treated silica (C) in the present invention can be obtained by treating silica particles with an aminosilane-based silane coupling agent. Details will be described below.

[I-3-1. Silica particles in silica treated with aminosilane (C)]
The silica particles in the aminosilane-treated silica (C) used in the present invention are not particularly limited, and examples include natural silica, fused silica, amorphous silica, and hollow silica. Among them, fused silica is particularly preferable from the viewpoint of low thermal expansion. Specific examples of the fused silica include SFP-130MC manufactured by Denki Kagaku Kogyo Co., Ltd., SC2050, SC2500, and SC4500 manufactured by Admatechs.

  Although the average particle diameter of a silica is not limited, 0.01-5.0 micrometers is preferable and 0.2-2.0 micrometers is more preferable from a viewpoint of the productivity improvement of a resin sheet. In the present specification, the “average particle size” of silica (C) treated with aminosilane means the median size of silica. Here, the median diameter means that when the particle size distribution of the powder is divided into two on the basis of a certain particle diameter, the mass of the particle on the larger particle size side and the mass on the smaller particle size side are all It means a particle size that occupies 50% of each powder. The average particle diameter (median diameter) of the aminosilane-treated silica (C) is measured by a wet laser diffraction / scattering method.

[I-3-2. Silane coupling agent in silica (C) treated with aminosilane]
Examples of the aminosilane-based silane coupling agent include γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, and phenylaminosilane. In particular, phenylaminosilane (KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.) is particularly preferable from the viewpoint of improving moisture absorption heat resistance.

  Although the content is not limited, from the viewpoint of improving moisture absorption heat resistance, the ratio of the silane coupling agent to the silica is preferably 0.05 to 5% by mass, and 0.1 to 3% by mass. More preferably. In addition, when using together 2 or more types of silane coupling agents, it is preferable that these total amount satisfy | fills the said ratio. One of these aminosilane-treated silicas (C) may be used alone, or two or more thereof may be used in any combination and ratio.

  Examples of the method for producing the above-described aminosilane-treated silica (C) include the following methods.

  The first method includes a dry method. Examples of the dry method include a method of directly attaching the arbitrary silane coupling agent to the arbitrary silica particles. Silica particles are charged into a mixer, and an alcohol solution or an aqueous solution of a silane coupling agent is added dropwise or sprayed with stirring, followed by further stirring and classification with a sieve. Thereafter, the aminosilane-treated silica (C) can be obtained by dehydrating condensation of the silane coupling agent and the silica particles by heating.

  The second method includes a wet method. In the wet method, an arbitrary silane coupling agent is added while stirring untreated slurry silica, and after stirring, classification is performed by filtration, drying, and sieving. Next, the aminosilane-treated silica (C) can be obtained by dehydrating and condensing the silane coupling agent and the silica particles by heating.

  As a third method, after adding an arbitrary silane coupling agent while stirring untreated slurry silica, dehydration condensation is advanced by heating and refluxing to obtain aminosilane-treated silica (C). A method is mentioned.

  As a fourth method, when preparing a varnish for producing an insulating layer, silica and an aminosilane-based silane coupling agent are added together with other components, and aminosilane-treated silica is formed in the step of forming the insulating layer. The method of producing | generating (C) is mentioned.

  As the aminosilane-treated silica (C) used in the resin composition of the present invention, a commercially available product can be used in addition to the above production method. Examples of commercially available products include slurry silica (SC2050-MTX, manufactured by Admatex Co., Ltd.) treated with phenylaminosilane (KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.).

  Among these, the first to third methods are preferable from the viewpoint of obtaining high plating peel strength while reducing the thermal expansion coefficient of the insulating layer. These methods are presumed to be because the amino group concentration on the silica surface becomes high and the adhesiveness with the matrix of the insulating layer is improved because the silica is treated with aminosilane in advance. However, since the insulating layer is usually cured, it is not practical to determine the concentration.

  The content of the aminosilane-treated silica (C) in the present invention is not particularly limited, but from the viewpoint of obtaining high plating peel strength while reducing the thermal expansion coefficient of the insulating layer, the resin solid content of the insulating layer is 100 parts by mass. On the other hand, it is preferable to set it as 50-350 mass parts, and it is preferable to set it as 70-300 mass parts. In addition, when using together 2 or more types of aminosilane-treated silica (C), it is preferable that these total amount satisfy | fills the said ratio.

[I-4. Acid-soluble inorganic filler (D)]
Although it will not specifically limit as a component (D) used for this invention if it is an inorganic filler soluble in an acid, Magnesium hydroxide and magnesium oxide are mentioned. The acid is preferably hydrochloric acid or sulfuric acid. These are eluted in the neutralizing solution in the desmear treatment of the insulating layer surface, and have the effect of forming a uniform roughened surface and improving the plating peel strength. Specifically, as magnesium hydroxide, Echo Mug Z-10, Echo Mug PZ-1 manufactured by Tateho Chemical Industry Co., Ltd., Magsees N, Magseeds S, Magseeds EP, Magseeds EP2-A manufactured by Kamishima Chemical Industry Co., Ltd. Examples thereof include MGZ-1, MGZ-3, MGZ-6R manufactured by Chemical Industry Co., Ltd., Kisuma 5, Kisuma 5A, Kisuma 5P manufactured by Kyowa Chemical Industry Co., Ltd., and the like. Examples of magnesium oxide include FNM-G manufactured by Tateho Chemical Industry Co., Ltd., SMO, SMO-0.1, SMO-S-0.5 manufactured by Sakai Chemical Industry Co., Ltd. These acid-soluble inorganic fillers (D) may be used alone or in combination of two or more in any combination and ratio.

  The average particle size of the acid-soluble inorganic filler (D) is preferably 0.1 to 2.0 μm from the viewpoint of obtaining uniform surface roughness after desmear treatment. The average particle diameter is the median diameter as described above.

  The content of the acid-soluble inorganic filler (D) is from the viewpoint of obtaining uniform surface roughness after desmear treatment and from the viewpoint of obtaining high plating peel strength, with respect to 100 parts by mass of the resin solid content of the insulating layer. It is preferable to set it as 20-150 mass parts, and it is preferable to set it as 30-130 mass parts.

  In addition, the acid-soluble inorganic filler (D) is preferably surface-treated from the viewpoint of moisture absorption heat resistance and chemical resistance. As the surface treatment agent, a silane coupling agent is preferable. Specific examples of the silane coupling agent include γ-aminopropyltriethoxysilane, aminosilanes such as N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, and γ-glycidoxypropyltrimethoxysilane. Epoxysilane, vinylsilane such as γ-methacryloxypropyltrimethoxysilane, cationic silane such as N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane hydrochloride, phenylsilane It is also possible to use one kind or a combination of two or more kinds as appropriate. Specifically, those treated with epoxy silane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) are preferable.

  When using a silane coupling agent, the content is not limited, but from the viewpoint of improving moisture absorption heat resistance, the ratio of the silane coupling agent to the component (D) is 0.05 to 5% by mass. It is preferable that the content be 0.1 to 3% by mass. In addition, when using together 2 or more types of silane coupling agents, it is preferable that these total amount satisfy | fills the said ratio.

[I-5. Maleimide Compound (E)]
In the present invention, it is preferable to use the maleimide compound (E) when improving the moisture absorption heat resistance of the insulating layer of the printed wiring board. The maleimide compound (E) used is not particularly limited as long as it is a compound having a maleimide group, and specifically, bis (4-maleimidophenyl) methane, 2,2-bis {4- (4-maleimide) Phenoxy) -phenyl} propane, bis (3,5-dimethyl-4-maleimidophenyl) methane, bis (3-ethyl-5-methyl-4-maleimidophenyl) methane, bis (3,5-diethyl-4-maleimide) Phenyl) methane, tris (4-maleimidophenyl) methane, a maleimide compound represented by the formula (5), a long-chain alkyl bismaleimide represented by the formula (6), and the like.

  Among these, the maleimide compound represented by the formula (5) is preferable from the viewpoint of moisture absorption heat resistance and flame resistance. Commercially available products can be used as the compound. Examples of such compounds include BMI-2300 manufactured by KAI Kasei Co., Ltd.

（式中、Ｒ^５は各々独立に、水素原子又はメチル基を表す。ｎ^５は平均値として１〜１０の範囲である。）

(In the formula, each R ⁵ independently represents a hydrogen atom or a methyl group. N ⁵ is in the range of 1 to 10 as an average value.)

  From the viewpoint of obtaining high plating peel strength, it is preferable to use a long-chain alkyl bismaleimide represented by the formula (6). A commercially available product can be used as the compound, and examples thereof include BMI-1000P manufactured by K. Kasei Chemical Co., Ltd.

（式中ｎ^６は、１以上３０以下の整数を示す。）

(Wherein n ⁶ represents an integer of 1 to 30)

  These maleimide compound prepolymers or maleimide compound and amine compound prepolymers can also be blended, and one or two or more of them can be used as appropriate.

  The content of the maleimide compound (E) in the present invention is preferably 5 to 50 parts by mass with respect to a total of 100 parts by mass of the epoxy compound (A), cyanate ester compound (B) and maleimide compound (E) component. Preferably, it is 5-20 mass parts. If the compounding quantity of a maleimide compound is the range of 5-50 mass parts, favorable moisture absorption heat resistance can be obtained.

[I-6. Other ingredients
In the present invention, in addition to epoxy compound (A), cyanate ester compound (B), aminosilane-treated silica (C), acid-soluble inorganic filler (D) and maleimide compound (E), It may contain one or more other components as exemplified in.

  The insulating layer of the present invention may contain rubber from the viewpoint of improving the handleability of the resin sheet. The rubber is not limited as long as it is a commonly used rubber. Specific examples include natural rubber (NR), styrene-butadiene rubber (SBR), isoprene rubber (IR), butadiene rubber (BR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), butyl rubber (IIR), ethylene. -Propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), urethane rubber (U), silicone rubber, fluorine rubber (FKM). These rubbers may be used alone or in combination of two or more in any combination and ratio. In particular, acrylonitrile butadiene rubber (NBR) is preferable from the viewpoint of uniformity.

  The resin sheet of the present invention may contain a wetting and dispersing agent from the viewpoint of improving resin sheet productivity. The wetting and dispersing agent is not limited as long as it is a wetting and dispersing agent generally used in paints and the like. Specific examples include Disperbyk-110, -111, -180, -161, BYK-W996, -W9010, and -W903 manufactured by Big Chemie Japan. One of these wetting and dispersing agents may be used alone, or two or more thereof may be used in any combination and ratio.

  When the wetting and dispersing agent is used, its content is not limited, but from the viewpoint of improving the resin sheet productivity, the total amount of aminosilane-treated silica (C) and acid-soluble inorganic filler (D) is used. On the other hand, the ratio of the wetting and dispersing agent is preferably 0.1 to 5% by mass, and more preferably 0.5 to 3% by mass. In addition, when using 2 or more types of wet dispersing agents together, it is preferable that these total amount satisfy | fills the said ratio.

  The insulating layer of the present invention may contain a curing accelerator for the purpose of adjusting the curing speed. As a hardening accelerator, it is well-known as hardening accelerators, such as an epoxy compound and a cyanate ester compound, and if it is generally used, it will not specifically limit. Specific examples include organometallic salts containing metals such as copper, zinc, cobalt, nickel, manganese (for example, zinc octylate, cobalt naphthenate, nickel octylate, manganese octylate, etc.), imidazoles, and derivatives thereof (for example, 2 -Ethyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 2,4,5-triphenylimidazole, etc.), tertiary amines (eg triethylamine, tributylamine etc.) and the like. These hardening accelerators may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  When the curing accelerator is used, the content is not limited, but from the viewpoint of obtaining a high glass transition temperature, the ratio of the curing accelerator is 0.01 to 5 mass with respect to 100 mass parts of the resin solid content of the insulating layer. Part is preferable, and 0.05 to 4 parts by mass is more preferable. In addition, when using 2 or more types of hardening accelerators together, it is preferable that these total amount satisfy | fills the said ratio.

  The insulating layer of the present invention may contain other various polymer compounds or flame retardant compounds as long as the desired properties are not impaired. The polymer compound and the flame retardant compound are not limited as long as they are generally used. Examples of the polymer compound include various thermosetting resins and thermoplastic resins, oligomers thereof, and elastomers. Examples of flame retardant compounds include phosphorus-containing compounds (eg, phosphate esters, melamine phosphate, phosphorus-containing epoxy resins), nitrogen-containing compounds (eg, melamine, benzoguanamine, etc.), oxazine ring-containing compounds, silicone compounds, and the like. Can be mentioned. These polymer compounds or flame retardant compounds may be used alone or in combination of two or more in any combination and ratio.

  In addition, the insulating layer of the present invention may contain various additives for various purposes within a range where desired properties are not impaired. Examples of additives include UV absorbers, antioxidants, photopolymerization initiators, fluorescent brighteners, photosensitizers, dyes, pigments, thickeners, lubricants, antifoaming agents, dispersants, leveling agents, Examples include brighteners. These additives may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

[I-7. varnish〕
The said component (A)-(D) and the said other component as needed can be dissolved or disperse | distributed to a solvent, and it can be set as a varnish. Such a varnish can be suitably used as a varnish for producing the resin sheet of the present invention described later. The solvent is not limited as long as it can suitably dissolve or disperse the above-described components and does not impair the intended effect of the present invention. Specific examples include alcohols (methanol, ethanol, propanol etc.), ketones (eg acetone, methyl ethyl ketone, methyl isobutyl ketone etc.), amides (eg dimethylacetamide, dimethylformamide etc.), aromatic hydrocarbons (eg toluene) , Xylene, etc.). These organic solvents may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

[II-1. Resin sheet)
The resin sheet of the present invention has the above-described insulating layer of the present invention on the outer layer. When manufacturing a printed wiring board using the said resin sheet, you may peel or etch an outer layer from a resin sheet as needed.

  Although it does not specifically limit as said outer layer, A polymer film, metal foil, or a metal film can be used. Specific examples of the polymer film include polyvinyl chloride, polyvinylidene chloride, polybutene, polybutadiene, polyurethane, ethylene-vinyl oxide copolymer, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and other polyesters, polyethylene, polypropylene, and ethylene. -A film containing at least one resin selected from the group consisting of propylene copolymer, polymethylpentene, polyimide and polyamide, and a release film obtained by applying a release agent to the surface of these films, Among these, polyester, polyimide, and polyamide are particularly preferable, and among them, polyethylene terephthalate, which is a kind of polyester, is particularly preferable.

  Moreover, the thickness of a polymer film is not specifically limited, For example, 0.002-0.1 mm may be sufficient. Specific examples of the metal foil or metal film include a foil or film made of a metal such as copper or aluminum. Among them, a copper foil or a copper film is preferable, and an electrolytic copper foil, a rolled copper foil, a copper alloy film, or the like is particularly preferable. Can be used for The metal foil or metal film may be subjected to a known surface treatment such as nickel treatment or cobalt treatment. Although the thickness of metal foil or a metal film can be suitably adjusted with a use application, the range of 5-70 micrometers is suitable, for example.

  The method for producing the resin sheet of the present invention by forming the insulating layer of the present invention on the above outer layer is not limited. As an example, the above-mentioned varnish is applied to the surface of the above-mentioned outer layer, dried under heating or reduced pressure, the solvent is removed, and the varnish is solidified. The drying conditions are not particularly limited, but drying is performed so that the content ratio of the solvent to the total amount of the insulating layer thus formed is usually 10 parts by mass or less, preferably 5 parts by mass or less. The conditions for achieving such drying vary depending on the amount of the organic solvent in the varnish. For example, in the case of a varnish containing 30 to 60 parts by mass of the organic solvent, the drying is performed for about 3 to 10 minutes under a heating condition of 50 to 160 ° C. You can do it. Although the thickness of the insulating layer in the resin sheet of the present invention is not limited, it is 0.1 to 500 μm from the viewpoint of better removing light volatiles during drying and more effectively and reliably performing the function as a resin sheet. The range of is preferable. When the resin composition does not contain a solvent and has fluidity, the resin composition may be used like a varnish to form an insulating layer.

  In addition, when the insulating layer formed from the resin composition having varnish or fluidity is compared with a method formed by a different method (such as melting and pressing the resin), the former is the layer. Excellent uniformity and adhesion to the outer layer.

  The resin sheet of the present invention can be used as a build-up material for printed wiring boards. In the printed wiring board formed using the resin sheet of the present invention, the insulating layer of the present invention constitutes the insulating layer in the printed wiring board. The insulating layer in the printed wiring board is usually cured. The printed wiring board will be described in detail below.

[II-2. (Printed wiring board)
The printed wiring board of this invention can be obtained by using the resin sheet of this invention as a buildup material with respect to a core base material. The core substrate is a substrate that becomes a core in the build-up method, and is a metal foil-clad laminate in which the resin insulating layer is completely cured. On the surface of the core substrate, a conductor circuit is formed by a metal foil of a metal foil-clad laminate usually used in the industry, or a conductor layer obtained by peeling and plating the metal foil.

  The core base material is mainly a conductive layer (circuit) patterned on one or both sides of a glass epoxy substrate, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, thermosetting polyphenylene ether substrate or the like. It means what was done. Further, when the multilayer printed wiring board is manufactured, an intermediate product inner circuit board on which an insulating layer or a conductor layer is to be further formed is also included in the circuit board referred to in the present invention. The surface of the conductor layer (circuit) is preferably subjected to a roughening treatment in advance by a blackening treatment or the like from the viewpoint of adhesion of the insulating layer to the circuit board.

  The insulating layer of the resin sheet of the present invention is cured to constitute the insulating layer in the printed wiring board.

  Specifically, when the resin sheet of the present invention is used as a build-up material, the insulating layer of the resin sheet is surface-treated by a conventional method, and a wiring pattern (conductor layer) is formed by plating on the surface of the insulating layer. The printed wiring board of the present invention is obtained.

  Various other processes (for example, hole processing for forming via holes, through holes, etc.) may be added as necessary.

  Hereafter, each process for manufacturing the printed wiring board of this invention is demonstrated.

1) Surface treatment The surface treatment for the insulating layer is performed from the viewpoint of improving the adhesion between the insulating layer and the plated conductor layer, removing smear, and the like. Examples of the surface treatment include desmear treatment and silane coupling treatment. The desmear treatment preferably includes swelling, surface roughening and smear dissolution, and neutralization treatment. The roughening treatment is preferably carried out with a swelling agent and an alkaline oxidizing agent, and the neutralization treatment is preferably carried out with an acidic reducing agent. In the present invention, by using silica treated with an aminosilane-based coupling agent, collapse marks can be reduced and low surface roughness can be achieved.

  More preferably, the roughening treatment also serves to remove smears generated by the drilling step. In this case, since the roughening state varies depending on the degree of curing of the insulating layer, it is preferable to select optimum conditions for the later-described lamination molding conditions in combination with the subsequent roughening treatment conditions and plating conditions.

  In a preferred embodiment, the roughening treatment first swells the surface insulating layer using a swelling agent. The swelling agent is not limited as long as the wettability of the surface insulating layer is improved and the surface insulating layer can be swollen to the extent that oxidative decomposition is promoted in the next surface roughening and smear dissolution treatment. . Examples include alkaline solutions and surfactant solutions.

  The swollen surface is then treated with an oxidizing agent to oxidatively decompose and roughen the surface. At this time, smear generated in the process is also removed. Examples of the oxidizing agent include an alkaline permanganate solution, and preferred specific examples include an aqueous potassium permanganate solution and an aqueous sodium permanganate solution. Such oxidant treatment is called wet desmear, but in addition to the wet desmear, other known roughening treatments such as dry desmear by plasma treatment or UV treatment, mechanical polishing by buffing, sandblasting, etc. are carried out in an appropriate combination May be.

  Further, the oxidizing agent used in the pretreatment is neutralized with a reducing agent by neutralization treatment. Examples of the reducing agent include amine-based reducing agents, and preferred specific examples include acidic aqueous solutions such as hydroxylamine sulfate aqueous solution, ethylenediaminetetraacetic acid aqueous solution, and nitrilotriacetic acid aqueous solution.

  In forming a fine wiring pattern, the surface roughness of the insulating layer after the roughening treatment is preferably small. Specifically, the Rz value is preferably 4.0 μm or less, more preferably 2.0 μm or less. Since the surface irregularities after the roughening treatment are determined according to the degree of curing of the insulating layer, the conditions of the roughening treatment, etc., it is preferable to select optimum conditions for obtaining the desired surface irregularities. In particular, the insulating layer of the present invention is extremely suitable because it can ensure adhesion with the plated conductor layer even if the surface roughness is low.

2) Formation of conductor layer Examples of a method for forming a wiring pattern (conductor layer) by plating include a semi-additive method, a full additive method, and a subtractive method. Among these, the semi-additive method is preferable from the viewpoint of forming a fine wiring pattern.

  As an example of the pattern forming method by the semi-additive method, after forming a thin conductor layer on the surface of the insulating layer by electroless plating, etc., electrolytic plating is selectively performed using a plating resist (pattern plating), and then the plating resist And a method of forming a wiring pattern by etching an appropriate amount of the whole.

  As an example of a method of forming a pattern by a full additive method, there is a method of forming a wiring pattern by performing pattern formation in advance using a plating resist on the surface of an insulating layer and selectively attaching electroless plating or the like.

  An example of a pattern forming method using the subtractive method is a method of forming a wiring pattern by forming a conductive layer on the surface of an insulating layer by plating and then selectively removing the conductive layer using an etching resist. It is done. Or when the outer layer of a resin sheet is metal foil or a metal film, these can be etched and a wiring pattern can also be formed.

  When forming a wiring pattern by plating, it is preferable to dry after plating from the viewpoint of improving the adhesion strength between the insulating layer and the conductor layer. The pattern formation by the semi-additive method is performed by combining electroless plating and electrolytic plating. In this case, it is preferable to perform drying after the electroless plating and after the electrolytic plating. Drying after electroless plating is preferably performed at 80 to 180 ° C. for 10 to 120 minutes, for example, and drying after electrolytic plating is preferably performed at 130 to 220 ° C. for 10 to 120 minutes, for example. . Since the electroless plating layer is superior to the electroplating layer in layer uniformity, the two can be distinguished.

3) Others In order to manufacture a printed wiring board, the resin sheet of the present invention may be subjected to hole processing. This processing is performed for forming via holes, through holes, and the like. The hole processing is performed by using any one of known methods such as NC drill, carbon dioxide laser, UV laser, YAG laser, plasma, or a combination of two or more if necessary.

  The printed wiring board of the present invention can be a multilayer printed wiring board. For example, after forming the laminated board of the present invention that has been subjected to plating treatment, an inner layer circuit is formed thereon, and the resulting circuit is subjected to blackening treatment to obtain an inner layer circuit board. The resin sheet of the present invention is arranged on one side or both sides of the inner layer circuit board thus obtained, and further a metal foil (for example, copper or aluminum) or a release film (polyethylene film, polypropylene film, polycarbonate film, polyethylene terephthalate film, Multi-layer printed wiring by repeating the operation of placing a film with a release agent on the surface of an ethylenetetrafluoroethylene copolymer film, polyester film, polyimide film, polyamide film, etc. A board is manufactured.

Laminate molding uses a method generally used for laminate molding of ordinary laminates for printed wiring boards, such as a multistage press, a multistage vacuum press, a laminator, a vacuum laminator, an autoclave molding machine, and the temperature is, for example, 100 to 300. C., pressure is, for example, 0.1 to 100 kgf / cm ² (about 9.8 kPa to about 38 MPa), and heating time is appropriately selected within a range of, for example, 30 seconds to 5 hours. Further, if necessary, for example, post-curing may be performed at a temperature of 150 to 300 ° C. to adjust the degree of curing.

  Synthesis Examples, Examples and Comparative Examples are shown below to describe the present invention in detail, but the present invention is not limited to these.

[Production of cyanate ester compound]
Synthesis Example 1: Synthesis of α-naphthol aralkyl-type cyanate ester compound (7)

（式中、ｎ^７は平均値として３から４までの範囲である。）

(In the formula, n ⁷ is an average value ranging from 3 to 4.)

  A reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser was previously cooled to 0 to 5 ° C. with a saline solution, to which 7.47 g (0.122 mol) of cyanogen chloride and 35% hydrochloric acid 9. 75 g (0.0935 mol), 76 ml of water, and 44 ml of methylene chloride were charged.

  The α-naphthol aralkyl resin (SN485, OH group equivalent: 214 g / eq. Softening) represented by the following formula (8) is stirred with keeping the temperature in the reactor at −5 to + 5 ° C. and the pH at 1 or less. Point: A solution prepared by dissolving 20 g (0.0935 mol) of 86 ° C, Nippon Steel Chemical Co., Ltd.) and 14.16 g (0.14 mol) of triethylamine in 92 ml of methylene chloride was added dropwise over 1 hour using a dropping funnel. After completion of the dropwise addition, 4.72 g (0.047 mol) of triethylamine was further added dropwise over 15 minutes.

（式中、ｎ^８は平均値として３から４までの範囲である。）

(In the formula, n ⁸ is in the range from 3 to 4 as an average value.)

  After completion of the dropwise addition, the reaction solution was separated after stirring at the same temperature for 15 minutes, and the organic phase was separated. The obtained organic phase was washed twice with 100 ml of water, and then methylene chloride was distilled off under reduced pressure using an evaporator. Finally, the mixture was concentrated to dryness at 80 ° C. for 1 hour, and α- 23.5 g of cyanate esterified product of naphthol aralkyl resin (α-naphthol aralkyl type cyanate ester compound) was obtained.

[Preparation of resin composition and resin sheet]
Example 1
As an epoxy compound (A), a MEK solution (nonvolatile content: 70% by mass) of 85.7 parts by mass of a biphenyl aralkyl type epoxy compound (NC-3000-FH, epoxy equivalent: 320 g / eq., Manufactured by Nippon Kayaku Co., Ltd.) (60 parts by mass in terms of non-volatile content) As a cyanate ester compound (B), methyl ethyl ketone (hereinafter referred to as “MEK”) of α-naphthol aralkyl type cyanate ester compound (cyanate equivalent: 261 g / eq.) Obtained in Synthesis Example 1 ) 60 parts by mass (non-volatile content: 50% by mass) solution (30 mass parts in terms of non-volatile content), silica treated with aminosilane (C), phenylaminosilane-treated silica MEK slurry (SC2050-MTX, (Manufactured by Admatechs Co., Ltd., average particle size 0.5 μm, nonvolatile component 70 mass%) 1 part by mass (75 parts by mass in terms of non-volatile content), an acid-soluble inorganic filler (D), magnesium oxide MEK slurry (SMO-0.4, manufactured by Sakai Chemical Industry Co., Ltd., average particle size 0. 4 μm, non-volatile component 70% by mass) 21.4 parts by mass (15 parts by mass in terms of non-volatile content), as maleimide compound (E), novolak maleimide compound (BMI-2300, Keiki) represented by the following formula (5) -Ai Kasei Co., Ltd.) 5.0 parts by mass, bismaleimide compound (BMI-1000P, K. Ai Kasei Co., Ltd.) 5.0 parts by mass, 2,4,5-triphenylimidazole as a curing accelerator DMAc solution (made by Wako Pure Chemical Industries, Ltd.) 15 parts by mass (non-volatile content 20% by mass) 15 parts by mass (3 parts by mass in terms of non-volatile content) and zinc octylate MEK solution (non-volatile content 10% by mass) 0.8 parts by mass (non-volatile content) In conversion The .08 parts by weight) was added to the MEK solution. After the addition, the mixture is stirred for 30 minutes using a high-speed stirrer, epoxy compound (A), cyanate ester compound (B), aminosilane-treated silica (C), acid-soluble inorganic filler (D), A varnish containing a maleimide compound (E) was obtained. This varnish was applied to a 38 μm thick polyethylene terephthalate film (TR1-38, manufactured by Unitika Co., Ltd.) whose surface was coated with a release agent, and heated and dried at 100 ° C. for 3 minutes to form an insulating layer. A resin sheet having a terephthalate film as an outer layer was obtained.

（式中、Ｒ^５は各々独立に、水素原子又はメチル基を表す。ｎ^５は平均値として１〜１０の範囲である。）

(In the formula, each R ⁵ independently represents a hydrogen atom or a methyl group. N ⁵ is in the range of 1 to 10 as an average value.)

[Production of inner circuit board]
Glass cloth base material BT resin double-sided copper-clad laminate with inner layer circuit (copper foil thickness 18μm, substrate thickness 0.2mm, Mitsubishi Gas Chemical Co., Ltd. CCL-HL832NX type A) manufactured by MEC The inner surface circuit board was obtained by performing 1 μm etching with CZ8100 to roughen the copper surface.

[Production of printed wiring board]
The insulating layer surface of the obtained resin sheet was placed on the inner layer circuit board, and after vacuuming (5.0 MPa or less) for 30 seconds using a vacuum laminator (manufactured by Nichigo Morton), the pressure was 10 kgf / cm ² , Lamination molding was performed at a temperature of 100 ° C. for 30 seconds. Furthermore, the printed wiring board was obtained by performing lamination molding for 60 seconds at a pressure of 10 kgf / cm ² and a temperature of 100 ° C. The obtained printed wiring board was dried at 180 ° C. for 60 minutes to sufficiently advance the curing to obtain a printed wiring board.

Example 2
Varnish as in Example 1 except that the amount of magnesium oxide MEK slurry (SMO-0.4, nonvolatile content 70% by mass) was changed to 42.9 parts by mass (30.0 parts by mass in terms of nonvolatile content). (Resolution of resin composition) was prepared to obtain a resin sheet and a printed wiring board using the resin sheet.

Example 3
Varnish as in Example 1 except that the amount of magnesium oxide MEK slurry (SMO-0.4, nonvolatile content 70% by mass) was changed to 85.7 parts by mass (60.0 parts by mass in terms of nonvolatile content). (Resolution of resin composition) was prepared to obtain a resin sheet and a printed wiring board using the resin sheet.

Example 4
Varnish in the same manner as in Example 1 except that the amount of magnesium oxide MEK slurry (SMO-0.4, nonvolatile content 70% by mass) was changed to 178.6 parts by mass (125.0 parts by mass in terms of nonvolatile content). (Resolution of resin composition) was prepared to obtain a resin sheet and a printed wiring board using the resin sheet.

Example 5
The amount of magnesium oxide MEK slurry (SMO-0.4, non-volatile content 70% by mass) used was 85.7 parts by mass (non-volatile equivalent 60.0 parts by mass), phenylaminosilane-treated silica MEK slurry (SC2050-MTX, non-volatile) The varnish (resin composition solution) was prepared in the same manner as in Example 1 except that the amount of the active ingredient 70% by mass was 285.7 parts by mass (200 parts by mass in terms of non-volatile content). And the printed wiring board using the same was obtained.

Example 6
The amount of magnesium oxide MEK slurry (SMO-0.4, non-volatile content 70% by mass) used was 85.7 parts by mass (non-volatile equivalent 60.0 parts by mass), phenylaminosilane-treated silica MEK slurry (SC2050-MTX, non-volatile) The varnish (resin composition solution) was prepared in the same manner as in Example 1 except that the amount of the active ingredient (70% by mass) was changed to 428.6 parts by mass (300 parts by mass in terms of non-volatile content). And the printed wiring board using the same was obtained.

Example 7
Aminosilane-treated silica (SC2050-MTX, 70 mass parts of nonvolatile content) was completely replaced with untreated silica MEK slurry (SO-C2, 70 mass parts of nonvolatile content), and phenylaminosilane (KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.) in the varnish. A varnish (resin composition solution) was prepared in the same manner as in Example 1 except that was added later to obtain a resin sheet and a printed wiring board using the same.

Comparative Example 1
A varnish (resin composition solution) was prepared in the same manner as in Example 1 except that the amount of magnesium oxide MEK slurry (SMO-0.4, nonvolatile content 70% by mass) was 0 parts by mass, and a resin sheet And the printed wiring board using the same was obtained.

Comparative Example 2
Use amount of magnesium oxide MEK slurry (SMO-0.4, nonvolatile content 70% by mass) is 178.6 parts by mass (125.0 parts by mass in terms of nonvolatile content), phenylaminosilane-treated silica MEK slurry (SC2050-MTX, nonvolatile) The varnish (resin composition solution) was prepared in the same manner as in Example 1 except that the amount of the active ingredient (70% by mass) was 0 parts by mass to obtain a resin sheet and a printed wiring board using the same. .

Comparative Example 3
Varnish (Example 1) except that the aminosilane-treated silica MEK slurry (SC2050-MTX, nonvolatile content 70% by mass) was completely replaced with the epoxysilane-treated silica MEK slurry (SC2050-MB, nonvolatile content 70% by mass). Resin composition solution) was prepared to obtain a resin sheet and a printed wiring board using the resin sheet.

Comparative Example 4
Varnish (resin) in the same manner as in Example 1, except that the aminosilane-treated silica MEK slurry (SC2050-MTX, nonvolatile content 70 parts by mass) was completely replaced with vinylsilane-treated silica MEK slurry (SC2050-MNU, nonvolatile content 70 parts by mass). A solution of the composition) was prepared, and a resin sheet and a printed wiring board using the resin sheet were obtained.

[Evaluation of printed wiring board]
Wet roughening and conductive layer plating of printed wiring boards:
The printed wiring board outer layers obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were peeled off. With respect to the exposed insulating layer, the electroless copper plating process (MCD-PL, MDP-2, MAT-SP, MAB-4-C, MEL-3-APEA ver. 2) manufactured by Uemura Kogyo Co., Ltd. Then, electroless copper plating of about 0.8 μm was applied and dried at 130 ° C. for 1 hour. Subsequently, electrolytic copper plating was performed so that the thickness of the plated copper was 18 μm, and drying was performed at 180 ° C. for 1 hour. In this way, a sample in which a conductor layer (plated copper) having a thickness of 18 μm was formed on the insulating layer was prepared and subjected to the following evaluation.
(1) Plating copper adhesive force Using the sample prepared by the above procedure, the adhesive strength of the plated copper was measured three times according to JIS C6481, and the average value was obtained. For samples in which swelling occurred after drying after electrolytic copper plating, the swelling after plating was “Yes”, and for samples in which swelling did not occur, the swelling after plating was “No”. For the samples with plating swelling “existing”, the evaluation was performed using the non-swelled portion. The results are shown in Table 1.
(2) Surface Roughness After etching the surface-plated copper of the sample prepared by the above procedure, Rz (10-point average roughness) of the insulating layer surface by a 3000 times image using a laser microscope (VK-9500 made by Keyence). ) And Ra (arithmetic mean roughness). The results are shown in Table 1.
(3) Coefficient of thermal expansion (CTE)
Using a resin sheet having an insulating layer thickness of 0.05 mm cured at 180 ° C. for 2 hours, the temperature was raised from 25 ° C. to 250 ° C. at 10 ° C. per minute with a thermomechanical analyzer (TA Instruments Q400). The coefficient of thermal expansion from 150 ° C. to 150 ° C. was measured. The results are shown in Table 1.

As described above, when the resin sheet of the present invention is used as a material for an insulating layer of a printed wiring board, various effects such as excellent handling of the resin sheet and excellent adhesion between the insulating layer and the plated conductor layer, etc. Therefore, it is extremely useful as a material for an insulating layer of a printed wiring board.

Claims (12)

A resin sheet comprising an outer layer that is one type selected from the group consisting of a polymer film, a metal foil and a metal film, and an insulating layer laminated on the outer layer,
The resin sheet in which the insulating layer contains an epoxy compound (A), a cyanate ester compound (B), aminosilane-treated silica (C), and an acid-soluble inorganic filler (D).   2. The resin sheet according to claim 1, wherein the content of the aminosilane-treated silica (C) in the insulating layer is 50 to 350 parts by mass with respect to 100 parts by mass of the resin solid content.   The resin sheet of Claim 1 or 2 whose content in the insulating layer of the said inorganic filler (D) soluble in an acid is 20-150 mass parts with respect to 100 mass parts of resin solid content.   The resin sheet according to any one of claims 1 to 3, wherein the acid-soluble inorganic filler (D) is magnesium hydroxide or magnesium oxide.   The resin sheet according to any one of claims 1 to 4, wherein the resin composition further comprises a maleimide compound (E).   The resin sheet according to any one of claims 1 to 5, wherein the polymer film is any one selected from the group consisting of polyester, polyimide and polyamide.   The said insulating layer is a thing obtained by apply | coating the resin composition containing the said component (A)-(D) on an outer layer, drying under a heating or pressure reduction, and solidifying. The resin sheet as described in any one.   A printed wiring board provided with the insulating layer as described in any one of Claims 1-7 laminated | stacked on the circuit board which has a core base material and the conductor circuit formed on the core base material.   The printed wiring board according to claim 8, wherein the insulating layer is surface-treated and includes a conductor layer patterned on the surface.   The printed wiring board according to claim 9, wherein the surface treatment is a desmear treatment including a roughening treatment with a swelling agent and an alkaline oxidizing agent, and a neutralization treatment with an acidic reducing agent.   The printed wiring board according to claim 9 or 10, wherein the conductor layer includes a conductor layer formed by a semi-additive method or a conductor layer formed by a subtractive method. The printed wiring board according to claim 9 or 10, wherein the conductor layer includes a conductor layer obtained by etching an outer layer made of the metal foil or metal film according to claim 1.