JP2017193690A - Adhesive film for multilayer printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive film for a multilayer printed board excellent in embedding property of unevenness even when a silica filler is highly filled.SOLUTION: An adhesive film for a multilayer printed board has a resin composition layer obtained by layer formation of a resin composition containing (a) a novolak-based phenolic resin having a dispersion ratio (Mw/Mn) between a weight average molecular weight (Mw) of a number average molecular weight (Mn) of 1.05-1.8, (b) an epoxy resin represented by a general formula (1) and (c) an inorganic filler, on a support film, where an average particle size of (c) the inorganic filler in the resin composition layer is 0.1 μm or more, and a content of (c) the inorganic filler is 20-95 mass% in a resin solid content.SELECTED DRAWING: None

Description

  The present invention relates to an adhesive film for a multilayer printed wiring board.

  In recent years, multilayer printed wiring boards used in electronic devices, communication devices, and the like have been increasingly demanded not only for miniaturization, weight reduction, and higher wiring density, but also for higher processing speed. Accordingly, as a method for manufacturing a multilayer printed wiring board, a build-up method manufacturing technique in which interlayer insulating layers are alternately stacked on a wiring layer of a circuit board has attracted attention.

  In the build-up manufacturing technique, the interlayer insulating layer and the wiring layer are manufactured by a resin composition for forming the interlayer insulating layer (hereinafter also referred to as “resin composition for interlayer insulating layer”), a wiring layer, and the like. The copper foil for forming the film is pressed for a long time at a high temperature using a pressing device to thermally cure the resin composition for the interlayer insulating layer, and after obtaining an interlayer insulating layer having a copper foil, it is necessary A method of forming wiring using a so-called “subtractive method” in which via holes for interlayer connection are formed using a drill method, a laser method, etc., and then a copper foil is removed by etching leaving a necessary portion. However, it has been common in the past.

  However, in accordance with the demands for reducing the size and weight of the multilayer printed wiring board as described above, increasing the density of the wiring, etc., the resin composition for the interlayer insulating layer and the copper foil are quickly used at a high temperature using a vacuum laminator. After pressurization, the interlayer insulating layer resin composition is thermally cured at a high temperature using a dryer, etc., and via holes for interlayer connection are formed using a drill method, a laser method, etc. as necessary, and a plating method Therefore, a so-called “additive method” in which a wiring layer is formed in a necessary portion has attracted attention.

  The resin composition for an interlayer insulating layer used in the build-up method includes an aromatic epoxy resin and a curing agent having active hydrogen for the epoxy resin (for example, a phenolic curing agent, an amine curing agent, a carboxylic acid type). A combination of a curing agent and the like has been mainly used. Cured products obtained by curing with these curing agents are excellent in balance of physical properties, but water absorption is achieved by the generation of highly polar hydroxy groups due to the reaction between epoxy groups and active hydrogen of the curing agents. There is a problem in that the electrical characteristics such as increase in the dielectric constant, dielectric constant, and dielectric loss tangent are reduced. Moreover, when these hardening | curing agents were used, the problem that the storage stability of the resin composition was impaired had arisen.

On the other hand, it is known that a cyanate resin having a thermosetting cyanato group gives a cured product having excellent electric characteristics. However, the reaction in which the cyanato group forms an S-triazine ring by thermal curing requires, for example, curing at a high temperature of 230 ° C. for 120 minutes or more for a relatively long time. It was unsuitable as a resin composition for interlayer insulation layers for printed wiring boards.
As a method for lowering the curing temperature of the cyanate resin, a method in which a cyanate resin and an epoxy resin are used in combination and cured using a curing catalyst is known (see, for example, Patent Documents 1 and 2).

  In addition, the build-up layer is required to have a low thermal expansion coefficient (low CTE) due to demands for processing dimensional stability and reduction of warpage after semiconductor mounting, and efforts are being made to reduce the CTE. (For example, see Patent Documents 3 to 5). As the most mainstream method, many build-up layers have a low CTE by increasing the amount of silica filler (for example, 40 mass% or more in the build-up layer is a silica filler).

JP2013-40298A JP 2010-90237 A JP-T-2006-527920 JP 2007-87982 A JP 2009-280758 A

[1] When the silica filler is increased in order to reduce the CTE of the build-up layer, it tends to be difficult to bury the unevenness of the wiring pattern of the inner layer circuit by the build-up material. In addition, it is required to embed an inner layer circuit such as a through hole so that unevenness is reduced by a build-up material. If the silica filler is highly filled in order to reduce the CTE of the build-up material, it tends to be difficult to satisfy these requirements.

  The first invention was made to solve such a problem, and an object of the invention is to provide an adhesive film for a multilayer printed wiring board that is excellent in unevenness embedding even when the silica filler is highly filled. To do.

[2] As described above, by using a cyanate resin and an epoxy resin in combination, the curing temperature can be reduced, while the storage stability as a resin composition tends to decrease. Along with the decrease in storage stability, when the resin composition is stored or used as a resin film for an interlayer insulating layer, there may be a problem in handling properties such as cracking of the film. In particular, when the inorganic filler is highly filled for the purpose of lowering the CTE and improving the electrical characteristics, the film is more likely to be cracked. Therefore, it is desired to improve the handleability as a resin film for an interlayer insulating layer. ing.

  The second invention has been made to solve such a problem, and an interlayer insulating layer resin having excellent electrical characteristics, heat resistance and flame retardancy is obtained, and the resin for interlayer insulating layers is excellent in handleability. It is an object to provide a film, a multilayer resin film using the resin film for an interlayer insulating layer, and a multilayer printed wiring board.

[1] As a result of intensive studies to solve the first problem, the inventors of the present invention have a resin composition containing a specific novolac-type phenolic resin, a specific epoxy resin, and a specific inorganic filler. The inventors have found that the first problem can be solved by using an object, and have completed the present invention. That is, the first invention provides the following adhesive film.

  (A) a novolak type phenol resin having a dispersion ratio (Mw / Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) of 1.05 to 1.8, and (b) the following general formula (I ) And (c) an inorganic filler, and a resin composition layer formed by forming a layer on a support film, and the resin composition layer ( c) The adhesive film for multilayer printed wiring boards in which the average particle size of the inorganic filler is 0.1 μm or more, and the content of the inorganic filler (c) is 20 to 95% by mass in the resin solid content.

(In the formula, p represents an integer of 1 to 5.)

[2] The present inventors have found that the above-mentioned problems can be solved by the following invention as a result of intensive studies to solve the second problem.
That is, the second invention provides the following (1) to (16).
<1> A resin film for an interlayer insulating layer formed using a thermosetting resin composition containing (A) an epoxy resin, (B) a cyanate resin, (C) an inorganic filler, and (D) a phosphorus-containing compound. Yes,
(D) the phosphorus-containing compound is at least one selected from the group consisting of an aromatic phosphate ester, an aromatic condensed phosphate ester and a cyclic phosphazene;
(C) The resin film for interlayer insulation layers whose content of an inorganic filler is 50-85 mass parts with respect to 100 mass parts of solid content of the said thermosetting resin composition.
<2> The content of the phosphorus-containing compound (D) in the thermosetting resin composition is 0.1 to 20 parts by mass with respect to 100 parts by mass of the solid content of the thermosetting resin composition. The resin film for interlayer insulation layers as described in said <1>.
<3> (D) The resin film for an interlayer insulating layer according to <1> or <2>, wherein the phosphorus-containing compound does not contain a hydroxy group and an amino group.
<4> (D) The resin film for an interlayer insulating layer according to any one of <1> to <3>, wherein the phosphorus-containing compound is a compound represented by the following general formula (1).

(In the formula, each of R ^D1 independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, each n independently represents an integer of 1 to 5, and Ar ^D1 represents an alkyl group having 6 to 20 carbon atoms. Represents an arylene group.)

<5> (D) The resin film for an interlayer insulating layer according to any one of <1> to <3>, wherein the phosphorus-containing compound is a compound represented by the following general formula (2).

(In the formula, each R ^D2 is independently a halogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryloxy having 6 to 20 carbon atoms. Group.)

<6> (D) The phosphorus-containing compound is a compound represented by the general formula (2), and R ^D2 in the general formula (2) is a phenoxy group. Resin film for insulation layer.
<7> The resin film for an interlayer insulating layer according to any one of <1> to <6>, wherein the thermosetting resin composition further contains (E) a phenoxy resin.
<8> (E) The resin film for an interlayer insulating layer according to <7>, wherein the phenoxy resin contains an alicyclic structure.
<9> The content of (E) phenoxy resin in the thermosetting resin composition is 0.2 to 10 parts by mass with respect to 100 parts by mass of the solid content of the thermosetting resin composition. The resin film for interlayer insulation layers as described in <7> or <8>.
<10> The resin film for an interlayer insulating layer according to any one of <1> to <9>, wherein the thermosetting resin composition further contains (F) an active ester curing agent.
<11> The above <10, wherein the content of the (F) active ester curing agent in the thermosetting resin composition is 0.1 to 0.7 equivalents relative to the average equivalent of the (A) epoxy resin. The resin film for interlayer insulation layers as described in>.
<12> The resin film for an interlayer insulating layer according to any one of <1> to <11>, which is for forming a buildup layer of a multilayer printed wiring board.
<13> A multilayer resin film comprising the interlayer insulating layer resin film according to any one of <1> to <12> and an organic resin film.
<14> The multilayer resin film according to <13>, wherein the organic resin film has a thickness of 10 to 70 μm, and the interlayer insulating layer resin film has a thickness of 1 to 70 μm.
<15> Using at least one selected from the group consisting of the resin film for an interlayer insulating layer according to any one of <1> to <12> and the multilayer resin film according to <13) or <14> above. Multi-layer printed wiring board obtained.
<16> Use at least one selected from the group consisting of the resin film for an interlayer insulating layer according to any one of <1> to <12> and the multilayer resin film according to <13> or <14>. A method for manufacturing a multilayer printed wiring board, comprising the following steps.
(1) A step of laminating the interlayer insulating layer resin film or the multilayer resin film on one side or both sides of a circuit board.
(2) A step of thermosetting the resin film laminated in step (1) to form an insulating layer.
(3) A step of drilling the circuit board on which the insulating layer is formed in the step (2).
(4) A step of roughening the surface of the insulating layer with an oxidizing agent.
(5) A step of forming a conductor layer by plating on the surface of the roughened insulating layer.
(6) A step of forming a circuit in the conductor layer by a semi-additive method.

[1] According to the first invention, it is possible to provide an adhesive film for a multilayer printed wiring board that is excellent in unevenness embedding even when the silica filler is highly filled.

[2] According to the second invention, an interlayer insulating layer having excellent electrical characteristics, heat resistance and flame retardancy is obtained, and the interlayer insulating layer resin film and the interlayer insulating layer resin film having excellent handleability are obtained. The used multilayer resin film and multilayer printed wiring board can be provided.

[1] First Invention The adhesive film for a multilayer printed wiring board of the present invention has a dispersion ratio (Mw / Mn) of (a) weight average molecular weight (Mw) and number average molecular weight (Mn) of 1.05. -1.8 novolac type phenolic resin (hereinafter also referred to simply as “(a) novolac type phenolic resin”) and (b) an epoxy resin represented by the general formula (I) (hereinafter simply referred to as “(A ) Epoxy resin ”) and (c) an inorganic filler (hereinafter, also referred to as“ resin composition for adhesive film ”), and a resin composition obtained by forming a layer on a support film. An average particle size of (c) inorganic filler in the resin composition layer is 0.1 μm or more, and (c) the content of the inorganic filler is 20 to 95 of the resin solid content. It is an adhesive film for multilayer printed wiring boards which is mass%.

[Resin composition for adhesive film]
The resin composition for an adhesive film contains (a) a novolac type phenol resin, (A) an epoxy resin, and (c) an inorganic filler. Hereinafter, each of these components will be described.

<(A) Novolac type phenolic resin>
(A) The novolak-type phenol resin is used as a curing agent for an epoxy resin, and the dispersion ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) is 1.05-1. .8 range.

Such a (a) novolac type phenol resin can be produced by, for example, the production method described in Japanese Patent No. 4283773.
That is, a phenol compound and an aldehyde compound as raw materials, a phosphoric acid compound as an acid catalyst, a non-reactive oxygen-containing organic solvent as a reaction auxiliary solvent, and the two-layer separation state formed from these are, for example, mechanically stirred, Stir and mix by sonic waves, etc. to advance the reaction between the phenolic compound and the aldehyde compound as a cloudy heterogeneous reaction system (phase separation reaction) in which two layers (organic phase and aqueous phase) intermingle, and condensate (resin ) Can be synthesized.
Next, for example, a water-insoluble organic solvent (for example, methyl ethyl ketone, methyl isobutyl ketone, etc.) is added and mixed to dissolve the condensate, and the mixing is stopped and allowed to stand, and the organic phase (organic solvent phase) and (A) Novolac by separating the aqueous phase (phosphoric acid aqueous solution phase) and removing the aqueous phase to recover, while the organic phase is washed with hot water and / or neutralized and then the organic solvent is recovered by distillation. Type phenolic resin can be produced.
Since the above-described method for producing a novolak-type phenolic resin utilizes a phase separation reaction, the stirring efficiency is extremely important, and it is a reaction to increase the surface area of the interface as much as possible by miniaturizing both phases in the reaction system. Desirable from an efficiency standpoint, this facilitates the conversion of phenolic compounds to resins.

Examples of the phenol compound used as the raw material include phenol, orthocresol, metacresol, paracresol, xylenol, bisphenol compound, ortho substitution having a hydrocarbon group having 3 or more carbon atoms, preferably 3 to 10 carbon atoms in the ortho position. Examples thereof include a phenol compound and a para-substituted phenol compound having a hydrocarbon group having 3 or more carbon atoms, preferably 3 to 18 carbon atoms, in the para position. You may use these individually or in mixture of 2 or more types.
Here, examples of the bisphenol compound include bisphenol A, bisphenol F, bis (2-methylphenol) A, bis (2-methylphenol) F, bisphenol S, bisphenol E, and bisphenol Z.
Examples of ortho-substituted phenol compounds include 2-propylphenol, 2-isopropylphenol, 2-sec-butylphenol, 2-tert-butylphenol, 2-phenylphenol, 2-cyclohexylphenol, 2-nonylphenol, 2-naphthylphenol, and the like. Is mentioned.
Examples of the para-substituted phenol compound include 4-propylphenol, 4-isopropylphenol, 4-sec-butylphenol, 4-tert-butylphenol, 4-phenylphenol, 4-cyclohexylphenol, 4-nonylphenol, 4-naphthylphenol, 4-dodecylphenol, 4-octadecylphenol, etc. are mentioned.

  Examples of the aldehyde compound used as a raw material include formaldehyde, formalin, paraformaldehyde, trioxane, acetaldehyde, paraaldehyde, propionaldehyde, and the like. Among these, paraformaldehyde is preferable from the viewpoint of reaction rate. You may use these individually or in mixture of 2 or more types.

  The compounding molar ratio (F / P) of the aldehyde compound (F) and the phenol compound (P) is preferably 0.33 or more, more preferably 0.40 to 1.0, still more preferably 0.50 to 0.00. 90. By setting the blending molar ratio (F / P) within the above range, an excellent yield can be obtained.

The phosphoric acid compound used as the acid catalyst plays an important role in forming a phase separation reaction field with the phenol compound in the presence of water. As a phosphoric acid compound, aqueous solution types, such as 89 mass% phosphoric acid and 75 mass% phosphoric acid, can be used, for example. Moreover, you may use polyphosphoric acid, anhydrous phosphoric acid, etc. as needed.
From the viewpoint of controlling the phase separation effect, the content of the phosphate compound is, for example, 5 parts by mass or more, preferably 25 parts by mass or more, more preferably 50 to 100 parts by mass with respect to 100 parts by mass of the phenol compound. . In addition, when using 70 mass parts or more of phosphoric acid compounds, it is preferable to ensure safety by suppressing heat generation at the initial stage of the reaction by splitting into the reaction system.

The non-reactive oxygen-containing organic solvent as a reaction auxiliary solvent plays a very important role in promoting the phase separation reaction. As the reaction auxiliary solvent, it is preferable to use at least one compound selected from the group consisting of alcohol compounds, polyhydric alcohol ethers, cyclic ether compounds, polyhydric alcohol esters, ketone compounds, and sulfoxide compounds.
Examples of alcohol compounds include monohydric alcohols such as methanol, ethanol, and propanol, butanediol, pentanediol, hexanediol, ethylene glycol, propylene glycol, trimethylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, and tripropylene glycol. And dihydric alcohols such as polyethylene glycol and trihydric alcohols such as glycerin.
Examples of polyhydric alcohol ethers include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl methyl ether, and ethylene glycol. A glycol ether etc. are mentioned.
Examples of the cyclic ether compound include 1,3-dioxane and 1,4-dioxane, and examples of the polyhydric alcohol ester include glycol ester compounds such as ethylene glycol acetate. Examples of the ketone compound include acetone, methyl ethyl ketone (hereinafter also referred to as “MEK”), and methyl isobutyl ketone. Examples of the sulfoxide compound include dimethyl sulfoxide and diethyl sulfoxide.
Among these, ethylene glycol monomethyl ether, polyethylene glycol, and 1,4-dioxane are preferable.
The reaction auxiliary solvent is not limited to the above examples, and may be a solid as long as it has the above-mentioned characteristics and exhibits a liquid state at the time of reaction, each being used alone or in combination of two or more. May be.
Although it does not specifically limit as a compounding quantity of a reaction auxiliary solvent, For example, it is 5 mass parts or more with respect to 100 mass parts of phenolic compounds, Preferably it is 10-200 mass parts.

By further using a surfactant during the heterogeneous reaction step, the phase separation reaction can be promoted, the reaction time can be shortened, and the yield can be improved.
Examples of the surfactant include soap, alpha olefin sulfonate, alkylbenzene sulfonic acid and its salt, alkyl sulfate ester salt, alkyl ether sulfate ester salt, phenyl ether ester salt, polyoxyethylene alkyl ether sulfate ester salt, ether sulfone. Anionic surfactants such as acid salts and ether carboxylates; polyoxyethylene alkylphenyl ethers, polyoxyalkylene alkyl ethers, polyoxyethylene styrenated phenol ethers, polyoxyethylene alkylamino ethers, polyethylene glycol aliphatic esters, fats Monoglyceride, sorbitan aliphatic ester, pentaerythritol aliphatic ester, polyoxyethylene polypropylene glycol, aliphatic alkylol ama Nonionic surfactants such as de; monoalkyl ammonium chloride, dialkyl ammonium chloride, and cationic surfactants such as amine salt compounds.
Although the compounding quantity of surfactant is not specifically limited, For example, it is 0.5 mass part or more with respect to 100 mass parts of phenolic compounds, Preferably it is 1-10 mass parts.

  The amount of water in the reaction system affects the phase separation effect and production efficiency, but is generally 40% by mass or less on a mass basis. By making the amount of water 40% by mass or less, the production efficiency can be kept good.

  The reaction temperature between the phenol compound and the aldehyde compound varies depending on the type of phenol compound, reaction conditions, and the like, and is not particularly limited, but is generally 40 ° C. or higher, preferably 80 ° C. to reflux temperature, more preferably reflux temperature. . When the reaction temperature is 40 ° C. or higher, a sufficient reaction rate can be obtained. The reaction time varies depending on the reaction temperature, the blending amount of phosphoric acid, the water content in the reaction system, etc., but is generally about 1 to 10 hours.

  The reaction environment is usually atmospheric pressure, but from the viewpoint of maintaining the heterogeneous reaction that is a feature of the present invention, the reaction may be performed under pressure or under reduced pressure. For example, under a pressure of 0.03 to 1.50 MPa, the reaction rate can be increased, and a low-boiling solvent such as methanol can be used as a reaction auxiliary solvent.

(A) A novolak type phenol resin having a dispersion ratio (Mw / Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) of 1.05 to 1.8 by the production method of the novolak type phenol resin. Can be manufactured.
Although depending on the type of the phenol compound, for example, the following (a) novolac type phenol resin can be obtained depending on the range of the blending molar ratio (F / P) of the aldehyde compound (F) and the phenol compound (P).
When the blending molar ratio (F / P) is in the range of 0.33 or more and less than 0.80, the content of the monomer component of the phenol compound is, for example, 3 by gel permeation chromatography (GPC) area method. The content of the dimer component of the phenol compound is, for example, 5 to 95% by mass, preferably 10 to 95% by mass, and further the weight average molecular weight (Mw by GPC measurement). ) And the number average molecular weight (Mn), a novolak type phenol resin having a dispersion ratio (Mw / Mn) of 1.05 to 1.8, preferably 1.1 to 1.7, is produced in a high yield. Can do.

  (A) As a novolak-type phenol resin, a commercial item can be used, for example, "PAPS-PN2" (Asahi Organic Materials Co., Ltd. make, brand name), "PAPS-PN3" (Asahi Organic Materials Co., Ltd. stock) Company name, product name) and the like.

The resin composition for an adhesive film may be used in combination with (a) an epoxy resin curing agent other than the novolak type phenol resin (hereinafter also simply referred to as “epoxy resin curing agent”) as long as the effects of the present invention are not impaired. .
As an epoxy resin hardening | curing agent, (a) Various phenol resin compounds other than a novolak-type phenol resin, an acid anhydride compound, an amine compound, a hydragit compound etc. are mentioned, for example. Examples of the phenol resin compound include (a) novolak type phenol resins other than novolak type phenol resins, resol type phenol resins, and the like, and examples of acid anhydride compounds include phthalic anhydride, benzophenone tetracarboxylic dianhydride, and the like. Products, methyl hymic acid and the like. Examples of the amine compound include dicyandiamide, diaminodiphenylmethane, and guanylurea.

Among these epoxy resin curing agents, from the viewpoint of improving reliability, (a) novolac type phenol resins other than novolac type phenol resins are preferable.
Further, from the viewpoint of improving the peel strength of the metal foil and the peel strength of the electroless plating after chemical roughening, a triazine ring-containing novolak type phenol resin and dicyandiamide are preferable.
(A) As the novolak type phenolic resin other than the novolak type phenolic resin, a commercially available product may be used. Cresol novolak resins such as those manufactured by the company and trade names). Moreover, as a commercial item of a triazine ring containing novolak type phenol resin, for example, “Phenolite LA-1356” (manufactured by DIC Corporation, trade name), “Phenolite LA7050 series” (manufactured by DIC Corporation, trade name), etc. Examples of commercially available products of triazine-containing cresol novolak resins include “Phenolite LA-3018” (trade name, manufactured by DIC Corporation).

<(A) Epoxy resin>
(A) The epoxy resin is an epoxy resin represented by the following general formula (I).

  (In the formula, p represents an integer of 1 to 5.)

(A) As an epoxy resin, you may use a commercial item. Examples of commercially available (A) epoxy resins include “NC-3000” (epoxy resin having p of 1.7 in formula (1)) and “NC-3000-H” (p in formula (1) 2.8 epoxy resin) (all manufactured by Nippon Kayaku Co., Ltd., trade name) and the like.
The resin composition for an adhesive film may contain (A) an epoxy resin other than the epoxy resin, a polymer type epoxy resin such as a phenoxy resin, and the like as long as the effects of the present invention are not impaired.

<Curing accelerator>
The resin composition for adhesive films may contain a curing accelerator from the viewpoint of accelerating the reaction between (a) the novolac type phenol resin and (A) the epoxy resin. Examples of the curing accelerator include imidazole compounds such as 2-phenylimidazole, 2-ethyl-4-methylimidazole and 1-cyanoethyl-2-phenylimidazolium trimellitate; organophosphorus compounds such as triphenylphosphine; phosphonium borate Onium salts; amines such as 1,8-diazabicycloundecene; 3- (3,4-dichlorophenyl) -1,1-dimethylurea and the like. You may use these individually or in mixture of 2 or more types.

<(C) Inorganic filler>
The resin composition for adhesive films includes (c) an inorganic filler having an average particle size of 0.1 μm or more.
(C) Examples of inorganic fillers include silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, and titanium. Examples thereof include barium acid, strontium titanate, calcium titanate, bismuth titanate, titanium oxide, barium zirconate, and calcium zirconate. You may use these individually or in mixture of 2 or more types. Among these, silica is preferable from the viewpoint of lowering the thermal expansion coefficient of the interlayer insulating layer formed by curing the adhesive film.
(C) The shape of the inorganic filler is not particularly limited, but is preferably a spherical shape from the viewpoint of facilitating embedding of the through holes and circuit patterns formed in the inner layer circuit.

(C) The average particle diameter of the inorganic filler is 0.1 μm or more, preferably 0.2 μm or more, and more preferably 0.3 μm or more from the viewpoint of obtaining excellent embedding properties.
The content of the inorganic filler having an average particle diameter of less than 0.1 μm is preferably 3 vol% or less, more preferably 1 vol% or less in terms of solid content from the viewpoint of embedding properties, and an inorganic having an average particle diameter of less than 0.1 μm. More preferably, no filler is contained. In addition, (c) an inorganic filler may be used individually by 1 type, and the thing of a different average particle diameter may be mixed and used for it.

  (C) A commercially available product may be used as the inorganic filler. Examples of the commercially available (c) inorganic filler include, for example, “SO-C1” (average particle size: 0.25 μm), “SO-C2” (average particle size: 0.5 μm), which are spherical silica, “SO-C3” (average particle size: 0.9 μm), “SO-C5” (average particle size: 1.6 μm), “SO-C6” (average particle size: 2.2 μm) (all manufactured by Admatechs Corporation) ) And the like.

  (C) The inorganic filler may be subjected to a surface treatment. For example, when silica is used as the inorganic filler (c), a silane coupling agent treatment may be applied as the surface treatment. Examples of the silane coupling agent include amino silane coupling agents, vinyl silane coupling agents, and epoxy silane coupling agents. Among these, silica subjected to surface treatment with an aminosilane coupling agent is preferable.

The amount of the inorganic filler (c) in the adhesive film resin composition is defined as follows. First, the resin composition that forms a layer on the support film is dried at 200 ° C. for 30 minutes, the solvent contained in the resin composition is removed, and the weight (solid content) after the solvent is removed is measured. . The amount of (c) inorganic filler contained in the solid content is defined as the amount of (c) inorganic filler in the resin solid content.
In addition, as a method for measuring (c) the inorganic filler, when the amount of the solid content of the (c) inorganic filler to be blended is calculated in advance, the ratio in the solid content can be easily obtained. A calculation example in the case of using (c) an inorganic filler dispersed in a solvent (hereinafter also referred to as “(c) inorganic filler dispersion”) is shown below.
(C) The solid content of the inorganic filler (c) in the inorganic filler dispersion was 70% by mass as a result of calculation after drying at 200 ° C. for 30 minutes. As a result of blending the resin composition using 40 g of this (c) inorganic filler dispersion liquid, the total amount of the obtained resin composition was 100 g. A result of drying 100 g of the resin composition at 200 ° C. for 30 minutes and measuring the weight of the solid content after drying was 60 g. Since the amount of the (c) inorganic filler contained in the solid content is 40 g × 70 mass% = 28 g, the amount of the (c) inorganic filler in the resin solid content is 28/60 = 47 mass%. (46.6% by mass).

  The amount of the inorganic filler (c) in the adhesive film resin composition is preferably as large as possible from the viewpoint of lowering the thermal expansion coefficient of the interlayer insulating layer after thermosetting, but the wiring pattern of the inner circuit board to be formed In view of embedding irregularities and through holes, there is an appropriate amount of inorganic filler. From such a viewpoint, the content of the inorganic filler (c) is 20 to 95% by mass in the resin solid content, preferably 30 to 90% by mass, and more preferably 50 to 90% by mass. (C) When the content of the inorganic filler is 20% by mass or more, the thermal expansion coefficient can be lowered, and when it is 95% by mass or less, the embedding property can be kept good.

<Flame Retardant>
The resin composition for adhesive films may further contain a flame retardant.
Although it does not specifically limit as a flame retardant, For example, an inorganic flame retardant, a resin flame retardant, etc. are mentioned.
Examples of the inorganic flame retardant include aluminum hydroxide and magnesium hydroxide exemplified as (c) inorganic filler.
The resin flame retardant may be a halogen-based resin or a non-halogen-based resin, but it is preferable to use a non-halogen-based resin in consideration of environmental burden. The resin flame retardant may be blended as a filler or may have a functional group that reacts with the thermosetting resin.
A commercially available product can be used as the resin flame retardant. Examples of commercially available resin flame retardants to be blended as fillers include “PX-200” (trade name, manufactured by Daihachi Chemical Industry Co., Ltd.), which is an aromatic phosphate ester flame retardant, and a polyphosphate compound. “Exolit OP 930” (trade name, manufactured by Clariant Japan Co., Ltd.) and the like.
Examples of commercially available resin flame retardants having functional groups that react with thermosetting resins include epoxy phosphorus-containing flame retardants and phenol phosphorus-containing flame retardants. Examples of the epoxy-based phosphorus-containing flame retardant include “FX-305” (trade name, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). Examples of the phenol-based phosphorus-containing flame retardant include “HCA-HQ”. (Trade name) manufactured by Sanko Co., Ltd., “XZ92741” (trade name, manufactured by Dow Chemical Co., Ltd.), and the like. You may use these individually or in mixture of 2 or more types.

<Solvent>
It is preferable that the resin composition for adhesive films contains a solvent from a viewpoint of performing layer formation efficiently. Examples of the solvent include ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; acetate compounds such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; cellosolve, methyl carbitol, Examples thereof include carbitol compounds such as butyl carbitol; aromatic hydrocarbon compounds such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, diethylene glycol dimethyl ether, and propylene glycol monomethyl ether. You may use these individually or in mixture of 2 or more types.

<Residual solvent amount>
The amount of residual solvent in the adhesive film of the present invention varies depending on the material to be handled, but is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, and further preferably 2 to 10% by mass. When the amount of the residual solvent is 1% by mass or more, the handleability of the adhesive film is improved, and for example, occurrence of powder falling or cracking when cutting with a cutter can be suppressed. On the other hand, when it is 20% by mass or less, stickiness is suppressed and the film can be easily wound and unwound. Moreover, in order to enable unwinding, a protective film is often provided on the varnish-coated surface of the adhesive film after drying, but if the residual solvent amount is 20% by mass or less, the protective film and the adhesive film of the present invention Separation between them becomes easy.
Further, since the residual solvent is removed by drying and thermosetting in the process of producing the multilayer printed wiring board, it is preferable that the residual solvent is small from the viewpoint of environmental load, and the change in film thickness before and after drying and thermosetting is reduced. In order to achieve this, it is preferable that the amount is small.
In the production of the adhesive film of the present invention, it is preferable to determine the drying conditions so as to achieve a target residual solvent amount. Since the drying conditions vary depending on the type of solvent, the amount of the solvent, and the like contained in the resin composition, it is preferable to determine the drying conditions after performing the conditions in advance by each coating apparatus.

Here, the residual solvent amount in the present invention is the ratio (mass%) of the solvent contained in the resin composition layer of the support film, and can be defined as follows.
First, the weight (W _a ) of the support film is measured, and the weight (W _b ) after the resin composition layer is formed thereon is measured. Thereafter, the support film and the resin composition layer formed thereon are left in a dryer at 200 ° C. for 10 minutes, and the weight after drying (W _c ) is measured. It can be calculated by the following formula using the obtained weights (W _a ) to (W _c ).
Ratio of solvent (% by mass) = (1-((W _c ) − (W _a )) / ((W _b ) − (W _a ))) × 100

<Other ingredients>
The adhesive film of this invention may contain the other component in the range which does not inhibit the effect of this invention. Examples of other components include thickeners such as olben and benton; UV absorbers such as thiazole and triazole; adhesion imparting agents such as silane coupling agents; phthalocyanine blue, phthalocyanine green, iodin green, and disazo yellow. And colorants such as carbon black; and optional resin components other than those described above.

[Support film]
The support film in the present invention is a support for producing the adhesive film of the present invention, and is usually finally peeled off or removed when producing a multilayer printed wiring board. .

Although it does not specifically limit as a support body film, For example, an organic resin film, metal foil, a release paper etc. are mentioned.
Examples of the material for the organic resin film include polyolefin such as polyethylene and polyvinyl chloride; polyester such as polyethylene terephthalate (hereinafter also referred to as “PET”) and polyethylene naphthalate; polycarbonate and polyimide. Among these, PET is preferable from the viewpoints of price and handleability.
Examples of the metal foil include copper foil and aluminum foil. When copper foil is used for the support, the copper foil can be used as it is as a conductor layer to form a circuit. In this case, rolled copper, electrolytic copper foil, or the like can be used as the copper foil. Moreover, although the thickness of copper foil is not specifically limited, For example, what has a thickness of 2-36 micrometers can be used. When using thin copper foil, you may use copper foil with a carrier from a viewpoint of improving workability | operativity.
These support films and a protective film described later may be subjected to surface treatment such as mold release treatment, plasma treatment, corona treatment and the like. Examples of the release treatment include a release treatment with a silicone resin release agent, an alkyd resin release agent, a fluororesin release agent, and the like.
Although the thickness of a support body film is not specifically limited, From a viewpoint of handleability, 10-120 micrometers is preferable, 15-80 micrometers is more preferable, 15-70 micrometers is further more preferable.
The support film need not be a single component as described above, and may be formed of a plurality of layers (two or more layers) of different materials.

For example, when the support film has a two-layer structure, for example, as the first support film, the support film mentioned above is used, and as the second layer, an epoxy resin, an epoxy resin curing agent, The thing which has the layer formed from a filler etc. is mentioned. As the material used for the second layer, the materials listed in the materials used for the adhesive film of the present invention can also be used.
A layer formed on the first support film (may be a second layer or a plurality of layers of two or more layers) is a layer prepared with the intention of imparting a function, for example, It can be used for the purpose of improving adhesiveness with plated copper.
Although it does not restrict | limit especially as a formation method of a 2nd layer, For example, the method of apply | coating and drying the varnish which melt | dissolved and disperse | distributed each material in the solvent on the 1st layer support film is mentioned.

When the support film is formed of a plurality of layers, the thickness of the first support film is preferably 10 to 100 μm, more preferably 10 to 60 μm, and still more preferably 13 to 50 μm.
The thickness of the layer formed on the first support film (the second and subsequent layers may be two or more layers) is preferably 1 to 20 μm. When it is 1 μm or more, the intended function can be achieved, and when it is 20 μm or less, the economical efficiency as a support film is excellent.

  When the support film is formed of a plurality of layers, when the support film is peeled off, the layer (which may be two or more layers) to be left on the multilayer printed wiring board side together with the adhesive film of the present invention is peeled off. Or you may isolate | separate into the layer (two or more layers may be removed) removed.

[Protective film]
The adhesive film of the present invention may have a protective film. The protective film is provided on the surface opposite to the surface on which the support for the adhesive film is provided, and is used for the purpose of preventing adhesion of foreign substances and the like to the adhesive film and scratches. The protective film is peeled off before the adhesive film of the present invention is laminated on a circuit board or the like by laminating or hot pressing.
Although it does not specifically limit as a protective film, The material similar to a support body film can be used. Although the thickness of a protective film is not specifically limited, For example, what has a thickness of 1-40 micrometers can be used.

[Production method of adhesive film]
The adhesive film of this invention can be manufactured by apply | coating and drying the resin composition for adhesive films on a support body film. The obtained adhesive film can be rolled up and stored and stored. More specifically, for example, after each resin component is dissolved in the organic solvent, (c) an inorganic filler or the like is mixed to prepare a resin composition for an adhesive film, and the varnish is placed on the support film. It can be produced by coating, drying the organic solvent by heating, blowing hot air, or the like to form a resin composition layer on the support film.
In the adhesive film of the present invention, the resin composition layer formed on the support film may be in an uncured state obtained by drying or in a semi-cured (B-stage) state. Good.

  The method for coating the varnish on the support film is not particularly limited. For example, the coating method may be performed using a known coating apparatus such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, or a die coater. Can be applied. What is necessary is just to select a coating apparatus suitably according to the target film thickness.

[2] Second Invention Next, a resin film for an interlayer insulating layer, a multilayer resin film, and a multilayer printed wiring board according to the second invention will be described.

[Resin film for interlayer insulation layer]
The resin film for an interlayer insulating layer according to the second invention is a thermosetting resin composition (hereinafter referred to as "A" epoxy resin, (B) cyanate resin, (C) inorganic filler, and (D) phosphorus-containing compound. , Also referred to as “interlayer insulating layer resin composition”), and (D) a phosphorus-containing compound comprising an aromatic phosphate, an aromatic condensed phosphate, and a cyclic It is at least one selected from the group consisting of phosphazenes, and the content of (C) inorganic filler is 50 to 85 parts by mass with respect to 100 parts by mass of the solid content of the thermosetting resin composition. It is a resin film for insulating layers.
In the present specification, the “solid content” means a non-volatile content excluding a volatile substance such as a solvent, and indicates a component that does not evaporate when the resin composition is dried, and is liquid at room temperature. In addition, water-like and waxy forms are included. Here, room temperature in this specification indicates 25 ° C.
In addition, the resin film for interlayer insulation layers may generally be called an interlayer insulation film.

<Resin composition for interlayer insulation layer>
The resin composition for an interlayer insulating layer used for forming the resin film for an interlayer insulating layer according to the second invention comprises (A) an epoxy resin, (B) a cyanate resin, (C) an inorganic filler, and (D) containing phosphorus. Contains compounds. Hereinafter, each component will be described.

[(A) Epoxy resin]
(A) Although it does not specifically limit as an epoxy resin, For example, the epoxy resin which has a 2 or more epoxy group in 1 molecule is mentioned preferably.
Examples of the epoxy resin (A) include glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, and the like. Among these, a glycidyl ether type epoxy resin is preferable.
(A) Epoxy resins are also classified according to the difference in main skeleton, and in each of the above-mentioned types of epoxy resins, bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, etc. Phenol novolac type epoxy resins, alkylphenol novolak type epoxy resins, cresol novolak type epoxy resins, naphthol alkylphenol copolymer novolak type epoxy resins, bisphenol A novolak type epoxy resins, bisphenol F novolak type epoxy resins, aralkyl novolak type epoxy resins and the like Type epoxy resin; stilbene type epoxy resin; triazine skeleton-containing epoxy resin; fluorene skeleton-containing epoxy resin; naphthalene type epoxy Is classified into dicyclopentadiene type alicyclic epoxy resin epoxy resin; resin; triphenylmethane type epoxy resins; biphenyl type epoxy resin; xylylene type epoxy resin. Examples of the aralkyl novolak type epoxy resin include an aralkyl cresol copolymer novolak type epoxy resin having a naphthol skeleton and an aralkyl novolak type epoxy resin having a biphenyl skeleton. (A) An epoxy resin may be used individually by 1 type, and may use 2 or more types together.
Among these, a novolac type epoxy resin is preferable from the viewpoints of the handleability of the resin film for the interlayer insulating layer and the electrical properties, heat resistance and flame retardancy of the resulting interlayer insulating layer, and the cresol novolac type epoxy resin and the bisphenol A novolak are preferable. A type epoxy resin is more preferable. From the same viewpoint, it is preferable to use a cresol novolac type epoxy resin and a bisphenol A novolac type epoxy resin in combination.
When a cresol novolac type epoxy resin and a bisphenol A novolac type epoxy resin are used in combination, the mass ratio (cresol novolac type epoxy resin / bisphenol A novolak type epoxy resin) can be obtained as well as the handleability of the resin film for the interlayer insulating layer. 40/60 to 90/10 are preferable, 50/50 to 80/20 are more preferable, and 60/40 to 70/30 are even more preferable from the viewpoints of electrical characteristics, heat resistance, and flame retardancy of the interlayer insulating layer.

  Moreover, the (A) epoxy resin may contain a liquid epoxy resin at room temperature from the viewpoint of improving the handleability of the resin film for an interlayer insulating layer. Although it does not restrict | limit especially as a liquid epoxy resin, Bifunctional liquid epoxy resins, such as a bisphenol A liquid epoxy resin, etc. are mentioned. (A) When the epoxy resin contains a liquid epoxy resin, the content is preferably 2 to 30% by mass with respect to (A) the epoxy resin, from the viewpoint of improving the handleability of the resin film for an interlayer insulating layer, More preferably, it is 4-20 mass%, More preferably, it is 6-15 mass%.

(A) The epoxy equivalent of the epoxy resin is preferably 120 to 500 g / eq, from the viewpoints of the handleability of the resin film for an interlayer insulating layer, and the electrical characteristics, heat resistance and flame retardancy of the interlayer insulating layer obtained, 350 g / eq is more preferable, and 180 to 250 g / eq is more preferable.
Here, the epoxy equivalent is the mass of the resin per epoxy group (g / eq), and can be measured according to the method defined in JIS K 7236 (2001). Specifically, using an automatic titration device “GT-200 type” manufactured by Mitsubishi Chemical Analytech Co., Ltd., 2 g of epoxy resin was weighed into a 200 ml beaker, 90 ml of methyl ethyl ketone was dropped, dissolved in an ultrasonic cleaner, iced It is obtained by adding 10 ml of acetic acid and 1.5 g of cetyltrimethylammonium bromide and titrating with a 0.1 mol / L perchloric acid / acetic acid solution.

  The content of the epoxy resin (A) in the resin composition for an interlayer insulating layer is determined from the viewpoint of the handleability of the resin film for the interlayer insulating layer, and the electrical characteristics, heat resistance and flame retardancy of the resulting interlayer insulating layer. 5-50 mass parts is preferable with respect to 100 mass parts of solid content of the resin composition for insulating layers, 10-35 mass parts is more preferable, and 15-25 mass parts is further more preferable.

[(B) cyanate resin]
(B) Although it does not specifically limit as cyanate resin, For example, cyanate resin which has a 2 or more cyanato group in 1 molecule is mentioned preferably.
(B) As the cyanate resin, 2,2-bis (4-cyanatophenyl) propane [bisphenol A type cyanate resin], bis (4-cyanatophenyl) ethane [bisphenol E type cyanate resin], bis (3 5-dimethyl-4-cyanatophenyl) methane [tetramethylbisphenol F type cyanate resin], 2,2-bis (4-cyanatophenyl) -1,1,1,3,3,3-hexafluoropropane [ Bisphenol type cyanate resin such as hexafluorobisphenol A type cyanate resin]; dicyclopentadiene type cyanate resin such as cyanate ester compound of phenol-added dicyclopentadiene polymer; phenol novolac type cyanate ester compound, cresol novolak type cyanate ester compound, etc. Novo Click type cyanate resin; alpha,. Alpha .'- bis (4-cyanatophenyl)-m-diisopropylbenzene; prepolymers of these cyanate resins (hereinafter also referred to as "cyanate prepolymer"), and the like. (B) Cyanate resin may be used individually by 1 type, and may use 2 or more types together.
Among these, bisphenol type cyanate resin, novolak type cyanate resin, and these prepolymers are used from the viewpoints of the handling property of the resin film for the interlayer insulating layer and the electrical characteristics, heat resistance and flame retardancy of the resulting interlayer insulating layer. preferable. As the bisphenol type cyanate resin, a dicyanate resin represented by the following general formula (3) is preferable.

(In the formula, R ^B1 represents an alkylene group having 1 to 5 carbon atoms which may be substituted with a halogen atom, an alkylidene group having 2 to 5 carbon atoms, a sulfur atom, the following general formula (3-1) or the following formula ( 3-2) represents a divalent group, and R ^B2 and R ^B3 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)

(In the formula, R ^B4 each independently represents an alkylene group having 1 to 5 carbon atoms or an alkylidene group having 2 to 5 carbon atoms.)

In the general formula (3), the alkylene group having 1 to 5 carbon atoms represented by R ^B1 includes a methylene group, an ethylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, Examples include 1,5-pentamethylene group.
In General Formula (3), examples of the alkylidene group having 2 to 5 carbon atoms represented by R ^B1 include an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group, and an isopentylidene group.
Examples of the halogen atom that substitutes the alkylene group having 1 to 5 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
In General Formula (3-1), the alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by R ^B4 are described in the same manner as in R ^B1 in General Formula (3).
Among these groups represented by R ^B1 , a methylene group and a propylidene group are preferable, and a propylidene group is more preferable.
In the general formula (3), the alkyl group having 1 to 4 carbon atoms represented by R ^B2 and R ^B3 includes methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and t-butyl. Groups and the like. R ^B2 and R ^B3 are preferably hydrogen atoms.

The cyanate prepolymer refers to a polymer in which a cyanate resin forms a triazine ring by a cyclization reaction, and examples thereof include 3, 5, 7, 9, and 11 mer of cyanate ester compounds. In this cyanate prepolymer, the conversion rate of the cyanate group is preferably 20 to 70% by mass, and more preferably 30 to 65% by mass from the viewpoint of obtaining good solubility in an organic solvent.
As the cyanate prepolymer, a dicyanate compound having two cyanate groups in one molecule is considered from the viewpoints of the handleability of the resin film for the interlayer insulating layer and the electrical characteristics, heat resistance and flame retardancy of the interlayer insulating layer to be obtained. A prepolymer is preferable, a prepolymer of a dicyanate resin represented by the general formula (3) is more preferable, and at least a part of the bisphenol A type cyanate resin is triazine to form a trimer. Further preferred are prepolymers represented.

The weight average molecular weight (Mw) of the cyanate prepolymer is preferably from 500 to 4,500, more preferably from 600 to 4,000, and even more preferably from 1,000 to 4,000, from the viewpoints of solubility in organic solvents and workability. Preferably, 1,500 to 4,000 are particularly preferable. If the weight average molecular weight of the cyanate prepolymer is 500 or more, crystallization of the cyanate prepolymer tends to be suppressed, and the solubility in an organic solvent tends to be good. If it is 4,500 or less, the viscosity increases. Is suppressed and the workability tends to be excellent.
A weight average molecular weight is the value measured by the gel permeation chromatography (GPC) method (polystyrene conversion), and can be measured by the method as described in an Example.

The cyanate prepolymer may be a prepolymer of a cyanate resin in the presence of a monofunctional phenol compound. Thereby, the unreacted cyanato group in the obtained hardened | cured material can be reduced, and it exists in the tendency for moisture resistance and an electrical property to be excellent.
Examples of monofunctional phenolic compounds include alkyl group-substituted phenolic compounds such as p-nonylphenol, p-tert-butylphenol, p-tert-amylphenol, and p-tert-octylphenol; p- (α-cumyl) phenol, mono-, Examples thereof include phenol compounds represented by the following general formula (5) such as di- or tri- (α-methylbenzyl) phenol. You may use these individually or in mixture of 2 or more types.

(In the formula, R ^B5 each independently represents a hydrogen atom or a methyl group, and m represents an integer of 1 to 3.)

  A compound having a group represented by —O—C (═NH) —O— (that is, iminocarbonate) is formed by the reaction between the cyanate resin and the monofunctional phenol compound, and the iminocarbonate further reacts with each other. Alternatively, by reacting the imino carbonate and the dicyanate compound, a monofunctional phenol compound is eliminated while a cyanate prepolymer having a triazine ring is obtained. The reaction is, for example, a cyanate resin and a monofunctional phenol compound mixed in the presence of a solvent such as toluene and dissolved, and maintained at 80 to 120 ° C., and a reaction such as zinc naphthenate is promoted as necessary. It can be performed by adding an agent.

  When a monofunctional phenol compound is used for producing a cyanate prepolymer, the amount of the monofunctional phenol compound used is equivalent to the phenolic hydroxyl group of the monofunctional phenol compound and the cyanate group of the cyanate resin used as the raw material of the cyanate prepolymer. The amount that the ratio (hydroxyl group / cyanato group) is 0.01 to 0.30 is preferable, the amount that 0.01 to 0.20 is more preferable, and the amount that 0.01 to 0.15 is more preferable. When the use amount of the monofunctional phenol compound is within the above range, in addition to a tendency that a dielectric loss tangent is sufficiently low particularly in a high frequency band, good moisture resistance tends to be obtained.

(B) As cyanate resin, you may use a commercial item. (B) As a commercial product of cyanate resin, “Primaset BADCy” (Lonza) and “Arocy B-10” (Huntsman), which are bisphenol A type cyanate resins, bisphenol E type Cyanate resins “Arocy L10” (manufactured by Huntsman) and “Primaset LECy” (manufactured by Lonza), and tetramethylbisphenol F type cyanate resin “Primaset METHYLCy” (Lonza) And “Primaset PT30” (manufactured by Lonza), which is a phenol novolac-type cyanate resin.
In addition, as a commercial product of a prepolymer of cyanate resin, “primaset BA200”, “primaset BA230S”, “primaset BA3000S”, which is a prepolymerized bisphenol A type cyanate resin ( As mentioned above, Lonza) and the like can be mentioned.
As cyanate resins other than the above, “Arocy XU-371” (manufactured by Huntsman), “Arocy XP71787.02L” (manufactured by Huntsman), which is a cyanate resin containing a dicyclopentadiene structure, “Primaset DT-4000” (manufactured by Lonza), “Primaset DT-7000” (manufactured by Lonza) and the like.

  The content of the (B) cyanate resin in the resin composition for an interlayer insulating layer is determined from the viewpoint of the handleability of the resin film for the interlayer insulating layer and the electrical characteristics, heat resistance and flame retardancy of the resulting interlayer insulating layer. 1-30 mass parts is preferable with respect to 100 mass parts of solid content of the resin composition for insulating layers, 2-22 mass parts is more preferable, and 3-10 mass parts is more preferable.

  The mass ratio [(A) / (B)] of (A) epoxy resin and (B) cyanate resin in the resin composition for interlayer insulation layers is the handleability of the resin film for interlayer insulation layers, and the obtained interlayer. 1-10 are preferable from a viewpoint of the electrical property of an insulating layer, heat resistance, and a flame retardance, 2-7 are more preferable, and 2.5-4 are more preferable. When the mass ratio [(A) / (B)] is 1 or more, the content of the (B) cyanate resin does not increase too much, and the increase in the curing temperature tends to be suppressed, and when it is 10 or less. The amount of unreacted epoxy groups in the obtained interlayer insulating layer tends to be reduced.

[(C) inorganic filler]
(C) As inorganic filler, silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate Strontium titanate, calcium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate and the like. Among these, silica is preferable from the viewpoints of the handleability of the resin film for an interlayer insulating layer and the electrical characteristics, heat resistance and flame retardancy of the resulting interlayer insulating layer. (C) An inorganic filler may be used individually by 1 type, and may use 2 or more types together.

(C) The volume average particle diameter of the inorganic filler is preferably 0.01 to 5 μm, more preferably 0.1 to 2 μm, from the viewpoint of obtaining good circuit board embedding and insulating reliability. 2 to 1 μm is more preferable.
The volume average particle diameter is a particle diameter at a point corresponding to a volume of 50% when a cumulative frequency distribution curve based on the particle diameter is obtained with the total volume of the particles being 100%, and the laser diffraction scattering method is used. It can be measured with a particle size distribution measuring device.
(C) The shape of the inorganic filler is preferably spherical from the viewpoint of pattern embedding.

  (C) A commercial item may be used for an inorganic filler. Commercially available (C) inorganic fillers include “SO-C1” (volume average particle size: 0.25 μm), “SO-C2” (volume average particle size: 0.5 μm), and “SO” which are spherical silica. -C3 "(volume average particle size: 0.9 μm),“ SO-C5 ”(volume average particle size: 1.6 μm),“ SO-C6 ”(volume average particle size: 2.2 μm) Admatechs).

(C) The inorganic filler may be surface-treated with a silane coupling agent from the viewpoint of improving moisture resistance. Silane coupling agents include aminosilane coupling agents, epoxysilane coupling agents, phenylsilane coupling agents, alkylsilane coupling agents, alkenylsilane coupling agents, mercaptosilane coupling agents, and isocyanate silanes. System coupling agents and the like. Among these, an aminosilane coupling agent is preferable from the viewpoint of storage stability of the resin composition for an interlayer insulating layer.
The surface treatment method using the silane coupling agent may be a dry or wet surface treatment method with respect to the inorganic filler before compounding. After forming the composition, a so-called integral blend treatment method in which a silane coupling agent is added to the composition may be used.

  The content of the inorganic filler (C) in the resin composition for an interlayer insulating layer is 100 parts by mass of the solid content of the resin composition for the interlayer insulating layer from the viewpoint of low thermal expansion, high frequency characteristics, and embedding in a wiring pattern. On the other hand, it is 50 to 85 parts by mass, preferably 55 to 80 parts by mass, and more preferably 60 to 75 parts by mass. (C) When the content of the inorganic filler is 50 parts by mass or more, good low thermal expansibility and high frequency characteristics tend to be obtained, and when it is 85 parts by mass or less, good embedding in a wiring pattern is possible. Tends to be obtained.

[(D) phosphorus-containing compound]
The resin composition for interlayer insulation layers contains at least one (D) phosphorus-containing compound selected from the group consisting of an aromatic phosphate ester, an aromatic condensed phosphate ester and a cyclic phosphazene. The resin film for an interlayer insulation layer of the present invention is formed using the resin composition for an interlayer insulation layer containing the (D) phosphorus-containing compound, whereby the electrical properties, heat resistance and flame retardancy of the interlayer insulation layer obtained are obtained. Excellent in handleability as a resin film.
(D) It is preferable that a phosphorus containing compound does not contain a hydroxyl group and an amino group from a viewpoint of improving the handleability of the resin film for interlayer insulation layers obtained.

(Aromatic phosphate ester)
Examples of the aromatic phosphate ester include triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, cresyl di-2,6-xylenyl phosphate and the like. Among these, triphenyl phosphate, tricresyl phosphate, and trixylenyl phosphate are preferable from the viewpoints of handleability of the resin film for an interlayer insulating layer and electrical characteristics, heat resistance, and flame retardancy of the interlayer insulating layer to be obtained.

(Aromatic condensed phosphate ester)
Examples of the aromatic condensed phosphate ester include compounds represented by the following general formula (1).

(In the formula, each of R ^D1 independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, each n independently represents an integer of 1 to 5, and Ar ^D1 represents an alkyl group having 6 to 20 carbon atoms. Represents an arylene group.)

In the general formula ^(1), the alkyl group having 1 to 4 carbon atoms represented by ^{R D1,} a methyl group, an ethyl group, n- propyl group, an isopropyl group, n- butyl group, an isobutyl group, a t- butyl group and the like are Can be mentioned. ^RD1 is preferably a hydrogen atom or a methyl group, and more preferably a methyl group, from the viewpoints of the handleability of the resin film for an interlayer insulating layer and the electrical characteristics, heat resistance, and flame retardancy of the resulting interlayer insulating layer.
In general formula (1), examples of the arylene group having 6 to 20 carbon atoms represented by Ar ^D1 include a phenylene group, a naphthylene group, a biphenylene group, and a divalent group represented by the following general formula (1-1). It is done.

(In the formula, R ^D3 represents an alkylene group having 1 to 5 carbon atoms and an alkylidene group having 2 to 5 carbon atoms.)

In general formula (1-1), the alkylene group having 1 to 5 carbon atoms represented by R ^D3 includes a methylene group, an ethylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, and 1,4-tetramethylene. Group, 1,5-pentamethylene group and the like.
In the general formula (1-1), the alkylidene group having 2 to 5 carbon atoms represented by R ^D3, ethylidene group, propylidene group, isopropylidene group, butylidene group, isobutylidene group, pentylidene group, isopentylidene group, and the like It is done.
The R ^D3, handling properties of the resin film for interlayer insulation layer, the electrical characteristics of the interlayer insulating layer obtained as well, in view of heat resistance and flame retardancy, methylene or isopropylidene group.

Among the groups represented by Ar ^D1 in the general formula (1), a phenylene group and a biphenylene group are used from the viewpoints of the handleability of the resin film for the interlayer insulating layer and the electrical characteristics, heat resistance, and flame retardancy of the interlayer insulating layer to be obtained. In addition, a divalent group in which R ^D3 in the general formula (1-1) is an isopropylidene group is preferable.

  The compound represented by the general formula (1) is represented by the following general formula (1 ′) from the viewpoint of the handleability of the resin film for an interlayer insulating layer and the electrical characteristics, heat resistance, and flame retardancy of the obtained interlayer insulating layer. It is preferable that it is a compound represented.

^{(Wherein, R D1} and ^{Ar D1} are the same as ^{R D1} and ^{Ar D1} of the general formula (1).)

  Specific examples of the aromatic condensed phosphate ester include 1,3-phenylene-bis (di-2,6-dimethylphenyl phosphate), 1,3-phenylene-bis (diphenyl phosphate), and bisphenol A bis (diphenyl phosphate). 1,4-phenylene-bis (di-2,6-dimethylphenyl phosphate), 4,4′-biphenylene-bis (di-2,6-dimethylphenyl phosphate), and the like.

(Cyclic phosphazene)
Examples of the cyclic phosphazene include compounds represented by the following general formula (2).

(In the formula, each R ^D2 is independently a halogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryloxy having 6 to 20 carbon atoms. Group.)

In the general formula (2), the halogen atom represented by R ^D2, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
In the general formula ^(2), the alkyl group having 1 to 10 carbon atoms represented by ^{R D2,} a methyl group, an ethyl group, n- propyl group, an isopropyl group, n- butyl group, an isobutyl group, t- butyl radical, n -A pentyl group, a hexyl group, an octyl group, a nonyl group, a decyl group, etc. are mentioned.
In the general formula (2), the aryl group having 6 to 20 carbon atoms represented by R ^D2, a phenyl group, a naphthyl group, an anthryl group, etc. biphenylyl group.
In the general formula (2), the alkoxy group having 1 to 10 carbon atoms represented by R ^D2, a methoxy group, an ethoxy group, n- propoxy group, hexyloxy group, nonyloxy group, decyloxy group and the like.
In the general formula (2), as the aryloxy group having 6 to 20 carbon atoms represented by R ^D2, phenoxy group, naphthoxy group, anthryl group, and a biphenylyl group and the like.
Among groups which these R ^D2 represents, preferably an aryloxy group having 6 to 20 carbon atoms, a phenoxy group is more preferable.

  The content of the (D) phosphorus-containing compound in the interlayer insulating layer resin composition is from the viewpoints of handleability of the resin film for interlayer insulating layer, and electrical properties, heat resistance and flame retardancy of the resulting interlayer insulating layer. 0.1-20 mass parts is preferable with respect to 100 mass parts of solid content of the resin composition for interlayer insulation layers, 0.5-10 mass parts is more preferable, 1-5 mass parts is more preferable, 1.5 -3 parts by weight is particularly preferred.

  From the same viewpoint, the phosphorus content in the interlayer insulating layer resin composition is 0.01 to 100 parts by mass of the solid content of the interlayer insulating layer resin composition excluding the inorganic filler (C). 3 mass parts is preferable, 0.1-2 mass parts is more preferable, 0.2-1.5 mass parts is further more preferable, and 0.3-1 mass part is especially preferable.

[(E) Phenoxy resin]
It is preferable that the resin composition for interlayer insulation layers contains (E) phenoxy resin.
Here, the “phenoxy resin” is a general term for polymers whose main chain is a polyaddition structure of an aromatic diol and an aromatic diglycidyl ether. In the present specification, the weight average molecular weight is 10,000 or more. Refers to things. When the polymer whose main chain is a polyaddition structure of aromatic diol and aromatic diglycidyl ether has an epoxy group, those having a weight average molecular weight of 10,000 or more are classified as (E) phenoxy resin, Those having an average molecular weight of less than 10,000 are classified as (A) epoxy resin.

(E) It is preferable that a phenoxy resin contains an alicyclic structure from a viewpoint of improving the handleability of the resin film for interlayer insulation layers. Here, the “alicyclic structure” means “an organic compound having a structure in which carbon atoms are bonded cyclically, excluding an aromatic compound”. Among these, at least one selected from cyclic saturated hydrocarbons (cycloalkanes) and cyclic unsaturated hydrocarbons having one double bond in the ring (cycloalkene) is preferable.
Examples of the (E) phenoxy resin include a phenoxy resin containing a cyclohexane structure, a phenoxy resin containing a trimethylcyclohexane structure, and a phenoxy resin containing a terpene structure. Among these, from the viewpoint of improving the handleability of the resin film for an interlayer insulating layer, a phenoxy resin containing one or more selected from a terpene structure and a trimethylcyclohexane structure is preferable, and a phenoxy resin containing a trimethylcyclohexane structure is more preferable. .
As a phenoxy resin containing a trimethylcyclohexane structure, a phenoxy resin using bisphenol TMC (bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane) as a raw material disclosed in JP-A-2006-176658 is disclosed. Etc.
As a phenoxy resin containing a terpene structure, for example, in the phenoxy resin disclosed in Japanese Patent Application Laid-Open No. 2006-176658, bis (4-hydroxyphenyl) -3,3,5- Examples thereof include phenoxy resins synthesized using terpene diphenol instead of trimethylcyclohexane.
(E) A phenoxy resin may be used individually by 1 type, and may use 2 or more types together.

(E) The weight average molecular weight of the phenoxy resin is preferably 10,000 to 60,000, more preferably 12,000 to 50,000, still more preferably 15,000 to 45,000, and 17,000 to 40,000. Is particularly preferable, and 20,000 to 37,000 is very preferable. (E) When the weight average molecular weight of the phenoxy resin is equal to or higher than the lower limit value, an excellent peel strength with the conductor layer tends to be obtained. An increase can be prevented.
A weight average molecular weight is the value measured by the gel permeation chromatography (GPC) method (polystyrene conversion), and can be measured by the method as described in an Example.

  (E) As a method for producing a phenoxy resin, for example, a bisphenol compound containing a trimethylcyclohexane structure or a bisphenol compound containing a terpene structure and a bifunctional epoxy resin are used as raw materials in accordance with a known phenoxy resin production method. It can manufacture by making it react in the range from which the equivalent ratio (phenolic hydroxyl group / epoxy group) of phenolic hydroxyl group becomes 1 / 0.9-1 / 1.1, for example.

  (E) A commercial item can be used for a phenoxy resin. The commercially available (E) phenoxy resin is derived from a biphenyl type epoxy resin and a bisphenol compound (1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane) containing a trimethylcyclohexane structure. "JER (registered trademark) YX7200B35" (trade name, manufactured by Mitsubishi Chemical Corporation) containing a skeleton is preferable.

  When the resin composition for interlayer insulation layers contains (E) phenoxy resin, the content thereof is preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the solid content of the resin composition for interlayer insulation layers, 1-7 mass parts is more preferable, and 2-4 mass parts is further more preferable. (E) When the content of the phenoxy resin is 0.2 parts by mass or more, the flexibility and the handleability tend to be excellent, and the peel strength of the conductor layer tends to be excellent. In addition to excellent stability and fluidity, an appropriate roughness tends to be obtained.

[(F) Active ester curing agent]
It is preferable that the resin composition for interlayer insulation layers contains (F) active ester hardening | curing agent. (F) By containing the active ester curing agent, the dielectric loss tangent tends to be reduced.
(F) Although it does not specifically limit as an active ester hardening | curing agent, For example, the compound which has 2 or more of ester groups in 1 molecule is mentioned preferably.
Specific examples include phenol esters, thiophenol esters, N-hydroxyamine esters, and heterocyclic hydroxy compound esters.

(F) The active ester curing agent is preferably obtained by a condensation reaction of at least one selected from a carboxylic acid compound and a thiocarboxylic acid compound and at least one selected from a hydroxy compound and a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester curing agent obtained from one or more selected from a carboxylic acid compound, a phenol compound, and a naphthol compound. More preferred.
Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid.
Examples of phenolic compounds include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol. Catechol, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyldiphenol, phenol novolac and the like.
Examples of the naphthol compound include α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene and the like. You may use these individually or in mixture of 2 or more types.

(F) As an active ester hardening | curing agent, the active ester hardening | curing agent currently disclosed by Unexamined-Japanese-Patent No. 2004-277460 may be used, and a commercial item can also be used.
Examples of commercially available (F) active ester curing agents include those containing a dicyclopentadienyl diphenol structure, acetylated phenol novolacs, benzoylated phenol novolacs, and the like.
As what contains a dicyclopentadienyl diphenol structure, "EXB9451", "EXB9460", "EXB9460S-65T", "HPC-8000-65T" (above, DIC Corporation make, active group equivalent 223g / eq) Etc.
Examples of the acetylated product of phenol novolac include “DC808” (manufactured by Mitsubishi Chemical Corporation, active group equivalent: 149 g / eq).
Examples of the benzoylated product of phenol novolak include “YLH1026” (active group equivalent 200 g / eq), “YLH1030” (active group equivalent 201 g / eq), “YLH1048” (active group equivalent 245 g / eq) (above, Mitsubishi Chemical Corporation). Manufactured) and the like.
Among these, from the viewpoint of the storage stability of varnish and the thermal expansion coefficient of the cured product, and from the viewpoint of obtaining an interlayer insulating layer excellent in reflow heat resistance, storage stability and smear removability, a dicyclopentadienyl diphenol structure is used. Including "HPC-8000-65T" is preferable.

  When the resin composition for interlayer insulation layers contains (F) active ester hardening | curing agent, the content is 0.1 to the average equivalent of (A) epoxy resin from a viewpoint of obtaining the outstanding electrical property. An amount of 0.7 equivalent is preferable, an amount of 0.2 to 0.6 equivalent is more preferable, and an amount of 0.3 to 0.5 equivalent is more preferable.

[(G) Curing accelerator]
The resin composition for interlayer insulation layers may contain the (G) hardening accelerator from a viewpoint which enables hardening for a short time at low temperature.
(G) As a hardening accelerator, a metal type hardening accelerator, an organic type hardening accelerator, etc. are mentioned.

(Metal curing accelerator)
As the metal curing accelerator, for example, an organometallic curing accelerator can be used. The organometallic curing accelerator has an action of promoting the self-polymerization reaction of the (B) cyanate resin and an action of promoting the reaction between the (A) epoxy resin and the (B) cyanate resin.
Examples of the organometallic curing accelerator include transition metals, organometallic salts of group 12 metals, organometallic complexes, and the like. Examples of the metal include copper, cobalt, manganese, iron, nickel, zinc, tin and the like.
Examples of the organic metal salt include carboxylates, and specific examples thereof include naphthenates such as cobalt naphthenate and zinc naphthenate, 2-ethylhexanoate cobalt and 2-ethylhexanoate zinc and the like. Examples include hexanoate, zinc octylate, tin octylate, tin stearate, and zinc stearate.
Examples of the organometallic complex include chelate complexes such as acetylacetone complex, and specific examples thereof include organocobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate; copper (II) acetylacetonate Organic copper complexes such as zinc (II) acetylacetonate; organic iron complexes such as iron (III) acetylacetonate; organonickel complexes such as nickel (II) acetylacetonate; manganese (II) acetyl And organic manganese complexes such as acetonate. Among these, from the viewpoint of curability and solubility, cobalt (II) acetylacetonate, cobalt (III) acetylacetonate, zinc (II) acetylacetonate, iron (III) acetylacetonate, zinc naphthenate, naphthene Cobalt acid is preferred. You may use these individually or in mixture of 2 or more types.

  When the resin composition for interlayer insulation layers contains a metal-type curing accelerator, the content is 10 to 10 mass by mass with respect to the solid content mass of (B) cyanate resin from the viewpoint of reactivity and storage stability. 500 ppm is preferable, 50 to 400 ppm is more preferable, and 150 to 300 ppm is more preferable. You may mix | blend a metal type hardening accelerator at once or in multiple steps.

(Organic curing accelerator)
Examples of organic curing accelerators (excluding the organometallic curing accelerators) include amine compounds such as organic phosphorus compounds, imidazole compounds, secondary amines, and tertiary amines; quaternary ammonium salts Etc. You may use these individually or in mixture of 2 or more types. Among these, from the viewpoint of removing smear in the via hole, an organic phosphorus compound, an imidazole compound, and an amine compound are preferable, and an organic phosphorus compound is more preferable. The organic curing accelerator may be blended at one time or divided into a plurality of times.

Examples of organophosphorus compounds include ethylphosphine, propylphosphine, butylphosphine, phenylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, trioctylphosphine, triphenylphosphine, tricyclohexylphosphine, triphenylphosphine / triphenylborane complex, tetraphenyl Examples thereof include phosphonium tetraphenylborate, an addition reaction product of a phosphine compound in which at least one alkyl group is bonded to a phosphorus atom and a quinone compound. Among these, triphenylphosphine and an addition reaction product of a phosphine compound in which at least one alkyl group is bonded to a phosphorus atom and a quinone compound are preferable.
As an addition reaction product of a phosphine compound in which at least one alkyl group is bonded to a phosphorus atom and a quinone compound, a phosphine compound in which one or more alkyl groups are bonded to a phosphorus atom represented by the following general formula (G-1) And an addition reaction product with a quinone compound represented by the following general formula (G-2).

(In General Formula (G-1), R ^G1 represents an alkyl group having 1 to 12 carbon atoms, and R ^G2 and R ^G3 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. In General Formula (G-2), R ^{G4 to} R ^G6 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and R ^G4 and R ^G5 are bonded to each other to form a cyclic structure. May be.)

Examples of the alkyl group having 1 to 12 carbon atoms represented by R ^G1 in the general formula (G-1) include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert. -Chain alkyl groups such as butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group; cyclic alkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclopentenyl group, cyclohexenyl group; benzyl group Aryl group-substituted alkyl groups such as; methoxy group-substituted alkyl groups, ethoxy group-substituted alkyl groups, butoxy group-substituted alkyl groups and other alkoxy group-substituted alkyl groups; dimethylamino groups, diethylamino groups and other amino group-substituted alkyl groups; Group and the like.
^The hydrocarbon group having 1 to 12 carbon atoms represented by ^{R G2} and ^{R G3,} a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 12 carbon atoms, a substituted or unsubstituted 1 to 12 carbon atoms Alicyclic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups having 1 to 12 carbon atoms, and the like.
Examples of the substituted or unsubstituted aliphatic hydrocarbon group having 1 to 12 carbon atoms include the same groups as the alkyl group having 1 to 12 carbon atoms represented by R ^G1 .
Examples of the substituted or unsubstituted alicyclic hydrocarbon group having 1 to 12 carbon atoms include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, an alkyl group, an alkoxy group, an aryl group, and a hydroxyl group. , Amino groups, halogen-substituted and the like.
Examples of the substituted or unsubstituted aromatic hydrocarbon group having 1 to 12 carbon atoms include aryl groups such as phenyl group and naphthyl group; tolyl group, dimethylphenyl group, ethylphenyl group, butylphenyl group, t-butylphenyl group, Alkyl group-substituted aryl groups such as dimethylnaphthyl group; alkoxy group-substituted aryl groups such as methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, t-butoxyphenyl group, methoxynaphthyl group; amino groups such as dimethylamino group and diethylamino group Substituted aryl groups; halogen-substituted aryl groups such as hydroxyphenyl groups and dihydroxyphenyl groups; aryloxy groups such as phenoxy groups and crezoxy groups; phenylthio groups, tolylthio groups, diphenylamino groups, and those substituted with amino groups, halogens, etc. Is mentioned. Of these, a substituted or unsubstituted alkyl group and aryl group are preferable.

  Examples of the phosphine compound represented by the general formula (G-1) include trialkylphosphine such as tricyclohexylphosphine, tributylphosphine, and trioctylphosphine; cyclohexyldiphenylphosphine, dicyclohexylphenylphosphine, butyldiphenylphosphine, dibutylphenylphosphine, and octyl. Alkyldiphenylphosphine such as diphenylphosphine and dioctylphenylphosphine; and dialkylphenylphosphine, and the like. From the viewpoint of varnish solubility, tributylphosphine, tri (p-methylphenyl) phosphine, tri (m-methylphenyl) phosphine, Tri (o-methylphenyl) phosphine is particularly preferred.

Examples of the hydrocarbon group having 1 to 18 carbon atoms represented by R ^{G4 to} R ^G6 in the general formula (G-2) include a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 18 carbon atoms and a carbon number. Examples thereof include a substituted or unsubstituted alicyclic hydrocarbon group having 1 to 18 carbon atoms and a substituted or unsubstituted aromatic hydrocarbon group having 1 to 18 carbon atoms.
Examples of the substituted or unsubstituted aliphatic hydrocarbon group having 1 to 18 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl. Group, octyl group, decyl group, dodecyl group and other alkyl groups; vinyl group, allyl group, propenyl group, butenyl group and other alkenyl groups; methoxy group, ethoxy group, propoxyl group, n-butoxy group, tert-butoxy group Alkoxy groups such as dimethylamino and diethylamino groups; alkylthio groups such as methylthio, ethylthio, butylthio, and dodecylthio; amino group-substituted alkyl groups, alkoxy-substituted alkyl groups, hydroxyl-substituted alkyl groups, aryl Substituted alkyl groups such as group-substituted alkyl groups; amino group-substituted alkoxy groups, hydroxyl groups Conversion alkoxy group, substituted alkoxy group such as an aryl group substituted alkoxy group.
Examples of the substituted or unsubstituted alicyclic hydrocarbon group having 1 to 18 carbon atoms include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, and an alkyl group, an alkoxy group, an aryl group, and a hydroxyl group. , Amino groups, halogen-substituted and the like.
Examples of the substituted or unsubstituted aromatic hydrocarbon group having 1 to 18 carbon atoms include aryl groups such as phenyl group and tolyl group; alkyl groups such as dimethylphenyl group, ethylphenyl group, butylphenyl group and t-butylphenyl group Substituted aryl group; alkoxy group substituted aryl group such as methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, t-butoxyphenyl group; aryloxy group such as phenoxy group, crezoxy group; phenylthio group, tolylthio group, diphenylamino group, etc. And those substituted with an amino group, halogen or the like.
Among them, a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted alkylthio group, and substituted or unsubstituted Of the arylthio group is preferred.

Further, the quinone compound represented by the general formula (G-2) may have a cyclic structure in which R ^G4 and R ^G5 are bonded. The quinone compound in which R ^G4 and R ^G5 are bonded to form a cyclic structure is represented by any one of the following general formulas (G-3) to (G-5) in which a substituted tetramethylene group, tetramethine group, or the like is bonded. And polycyclic quinone compounds.

(In General Formulas (G-3) to (G-5), R ^G6 is the same as that in General Formula (G-2).)

  Among the quinone compounds represented by the general formula (G-2), 1,4-benzoquinone and methyl-1,4-benzoquinone are preferable from the viewpoint of reactivity with the phosphine compound, and are curable at the time of moisture absorption. From the viewpoint, alkoxy group-substituted 1,4-benzoquinone such as 2,3-dimethoxy-1,4benzoquinone, 2,5-dimethoxy-1,4-benzoquinone and methoxy-1,4-benzoquinone; 2,3-dimethyl Preferred are alkyl group-substituted 1,4-benzoquinones such as -1,4-benzoquinone, 2,5-dimethyl-1,4-benzoquinone, and methyl-1,4-benzoquinone. From the viewpoint of storage stability, 2,5 -Di-t-butyl-1,4-benzoquinone, t-butyl-1,4-benzoquinone and phenyl-1,4-benzoquinone are preferred.

  As an addition reaction product of the phosphine compound represented by the general formula (G-1) and the quinone compound represented by the general formula (G-2), a compound represented by the following general formula (G-6) Etc.

(In General Formula (G-6), R ^{G1 to} R ^G6 are the same as those in General Formulas (G-1) and (G-2).)

As a method for producing an addition reaction product of a phosphine compound having at least one alkyl group bonded to a phosphorus atom and a quinone compound, for example, a phosphine compound and a quinone compound used as raw materials are added in an organic solvent in which both are dissolved. The method of isolating after making it react is mentioned.
The addition reaction product of the phosphine compound and the quinone compound in which at least one alkyl group is bonded to the phosphorus atom may be used alone or in combination of two or more.

  When the resin composition for interlayer insulation layers contains an organic hardening accelerator, the content is 0.001 with respect to 100 mass parts of (A) epoxy resin solid content from a viewpoint of reactivity and storage stability. 01-5 mass parts is preferable, 0.01-3 mass parts is more preferable, 0.01-2 mass parts is further more preferable.

<Other ingredients>
The resin composition for interlayer insulation layers may contain components other than the above components as long as the effects of the present invention are not impaired. Examples of other components include resin components other than the above components (hereinafter also referred to as “other resin components”), additives, flame retardants, and the like.

(Other resin components)
Examples of other resin components include a polymer of a bismaleimide compound and a diamine compound, a bismaleimide compound, a bisallyl nazide resin, and a benzoxazine compound.

(Additive)
Examples of additives include thickeners such as olben and benton; adhesion imparting agents such as imidazole, thiazole, triazole and silane coupling agents; rubber particles; colorants and the like.

(Flame retardants)
Examples of the flame retardant include an inorganic flame retardant and a resin flame retardant. Examples of the inorganic flame retardant include aluminum hydroxide and magnesium hydroxide. The resin flame retardant may be a halogen-based resin or a non-halogen-based resin, but a non-halogen-based resin is preferable in consideration of environmental load.

  The resin composition for interlayer insulation layers can be manufactured by mixing the components (A) to (D), the components (E) to (G) contained as necessary, and other components. As a mixing method, a known method can be applied. For example, the mixing may be performed using a bead mill or the like.

<Thickness of resin film for interlayer insulation layer>
The thickness of the resin film for interlayer insulation layers is 1-100 micrometers, for example, and may be 1-70 micrometers. Further, the thickness of the resin film for the interlayer insulating layer may be determined by the thickness of the conductor layer formed on the printed wiring board, and since the thickness of the conductor layer is usually 5 to 70 μm, the interlayer insulating layer The thickness of the resin film is preferably 10 to 100 μm, more preferably 15 to 80 μm, and still more preferably 20 to 50 μm from the viewpoint of enabling the multilayer printed wiring board to be thinned.

<Support>
The resin film for an interlayer insulating layer of the present invention may be formed on a support.
Examples of the support include organic resin films, metal foils, release papers, and the like.
Examples of the material for the organic resin film include polyolefin such as polyethylene and polyvinyl chloride; polyester such as polyethylene terephthalate (hereinafter also referred to as “PET”) and polyethylene naphthalate; polycarbonate and polyimide. Among these, PET is preferable from the viewpoints of price and handleability.
Examples of the metal foil include copper foil and aluminum foil. When copper foil is used for the support, the copper foil can be used as it is as a conductor layer to form a circuit. In this case, rolled copper, electrolytic copper foil, or the like can be used as the copper foil. Moreover, the thickness of copper foil can be 2-36 micrometers, for example. When using thin copper foil, you may use copper foil with a carrier from a viewpoint of improving workability | operativity.
As one embodiment of the present invention, a multilayer resin film having the interlayer insulating layer resin film and the organic resin film can be cited. As will be described later, the multilayer resin film may have an adhesion assisting layer together with a layer made of an interlayer insulating layer resin film (interlayer insulating layer resin composition layer).

These supports and a protective film described later may be subjected to surface treatment such as mold release treatment, plasma treatment, corona treatment and the like. Examples of the release treatment include a release treatment using a silicone resin release agent, an alkyd resin release agent, a fluororesin release agent, or the like.
The thickness of the support is preferably from 5 to 120 μm, more preferably from 10 to 70 μm, more preferably from 15 to 50 μm, and particularly preferably from 25 to 50 μm, from the viewpoints of handleability and economy.
When producing a multilayer printed wiring board, the support is usually finally peeled off or removed.

<Protective film>
A protective film may be arranged on the surface opposite to the support of the resin film for an interlayer insulating layer of the present invention. The protective film is provided on the surface opposite to the surface on which the support for the resin film for the interlayer insulating layer is provided, and prevents the adhesion and scratches of foreign matters to the resin film for the interlayer insulating layer. Used for purposes. The protective film is peeled off before the interlayer insulating layer resin film is laminated on a circuit board or the like by laminating or hot pressing.
As the protective film, the same material as the support can be used. For example, a protective film having a thickness of 1 to 40 μm can be used.

<Method for producing resin film for interlayer insulating layer>
The resin film for interlayer insulation layers of the present invention can be produced, for example, by applying a resin composition for interlayer insulation layers on a support and then drying. At that time, the resin composition for an interlayer insulating layer is preferably dissolved and / or dispersed in an organic solvent to form a varnish.

(Organic solvent)
Examples of organic solvents include ketone solvents such as acetone, methyl ethyl ketone (hereinafter also referred to as “MEK”), methyl isobutyl ketone, and cyclohexanone; acetic acid such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate. Examples include ester solvents; carbitol solvents such as cellosolve and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. You may use these individually or in mixture of 2 or more types. Among these, from the viewpoint of solubility, a ketone solvent is preferable, and MEK and methyl isobutyl ketone are more preferable.

  As a method of coating the resin composition for an interlayer insulating layer, a method of coating using a known coating apparatus such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, or a die coater can be applied. it can. What is necessary is just to select a coating apparatus suitably according to the target film thickness.

As drying conditions after coating the resin composition for interlayer insulation layers, it is preferable to dry so that the content of the organic solvent in the obtained resin film for interlayer insulation layers is 10% by mass or less. It is more preferable to dry so that it may become mass% or less.
Although drying conditions change also with the quantity and kind of organic solvent in a varnish, if it is a varnish containing 20-80 mass% organic solvent, what is necessary is just to dry for 1 to 10 minutes at 50-150 degreeC.

[Multilayer resin film having an auxiliary adhesion layer]
Next, a multilayer resin film having an adhesion auxiliary layer will be described as one embodiment of the multilayer resin film of the present invention.
The multilayer resin film having an adhesion auxiliary layer is a multilayer resin film having an organic resin film, an adhesion auxiliary layer, and a resin composition layer for an interlayer insulating layer comprising the resin film for an interlayer insulating layer of the present invention in this order. .

<Resin composition layer for interlayer insulation layer>
The resin composition layer for interlayer insulation layers is a layer which consists of the resin film for interlayer insulation layers of this invention, The suitable aspect is as the description of the resin film for interlayer insulation layers of this invention.
The resin composition layer for an interlayer insulating layer is a layer provided between a circuit board and an adhesion auxiliary layer in the case of producing a multilayer printed wiring board using a multilayer resin film having an adhesion auxiliary layer. The insulating layer obtained by curing the resin composition layer for layers serves to insulate the circuit patterns that have been multilayered, for example, in a multilayer printed wiring board. In addition, when a through hole, a via hole or the like is present in the circuit board, the resin composition layer for an interlayer insulating layer also flows in the circuit board and fills the inside of the hole.

  The thickness of the resin composition layer for interlayer insulation layers can be determined by the thickness of the conductor layer formed on the printed wiring board. Since the thickness of the conductor layer is usually 5 to 70 μm, the thickness of the resin composition layer for the interlayer insulating layer is preferably 10 to 100 μm, from the viewpoint of enabling the multilayer printed wiring board to be thinned. 15-80 micrometers is more preferable and 20-50 micrometers is further more preferable.

<Adhesion auxiliary layer>
The adhesion auxiliary layer is a layer that insulates the multilayered circuit patterns from each other in the multilayer printed wiring board that is multilayered by the build-up method, and that plays a role of smooth and high plating peel strength.
The thickness of the adhesion auxiliary layer is preferably 1 to 10 μm and more preferably 2 to 8 μm from the viewpoint of obtaining an interlayer insulating layer having high adhesion to the conductor layer.
An adhesion auxiliary layer can be formed using the resin composition for adhesion auxiliary layers.

(Resin composition for adhesion auxiliary layer)
The resin composition for an auxiliary adhesion layer preferably contains (H) a cyanate resin from the viewpoint of obtaining an interlayer insulating layer having a smooth surface and high adhesion to the conductor layer.

[(H) cyanate resin]
(H) As cyanate resin, the thing similar to (B) cyanate resin which the said resin composition for interlayer insulation layers contains is mentioned, A suitable aspect is also the same.
When the resin composition for an adhesion auxiliary layer contains the (H) cyanate resin, the content is for the adhesion auxiliary layer from the viewpoint of obtaining an interlayer insulating layer having a smooth surface and high adhesion to the conductor layer. 5-50 mass parts is preferable with respect to 100 mass parts of solid content of a resin composition, 10-40 mass parts is more preferable, and 20-35 mass parts is further more preferable.

[(J) Epoxy resin]
It is preferable that the resin composition for an adhesion auxiliary layer further contains (J) an epoxy resin.
(J) As an epoxy resin, the thing similar to the (A) epoxy resin which the said resin composition for interlayer insulation layers can contain is mentioned. Among these, from the viewpoint of excellent reflow heat resistance of the obtained interlayer insulating layer, an aralkyl novolak type epoxy resin is preferable, and an aralkyl novolak type epoxy resin having a biphenyl skeleton is more preferable.
The aralkyl novolak type epoxy resin having a biphenyl skeleton means an aralkyl novolak type epoxy resin containing an aromatic ring of a biphenyl derivative in the molecule, and an epoxy resin containing a structural unit represented by the following general formula (6) Etc.

(In the formula, R ^J1 represents a hydrogen atom or a methyl group.)

The content of the structural unit represented by the general formula (6) in the epoxy resin containing the structural unit represented by the general formula (6) has a small surface roughness after desmearing, and is a conductor formed by plating. From the viewpoint of obtaining an interlayer insulating layer excellent in adhesive strength with the layer, 50 to 100% by mass is preferable, 70 to 100% by mass is more preferable, and 80 to 100% by mass is further preferable.
From the same viewpoint, the epoxy resin containing the structural unit represented by the general formula (6) is preferably an epoxy resin represented by the following general formula (6 ′).

^{(Wherein, R J1} is the same as ^{R J1} in the general formula (6) in, s is. Represents an integer of 1 to 20)

  In the general formula (6 ′), s is preferably an integer of 1 to 10, more preferably an integer of 1 to 8, from the viewpoint of reducing the surface roughness after desmearing.

When the resin composition for an adhesion auxiliary layer contains (J) an epoxy resin, the content is for the adhesion auxiliary layer from the viewpoint of obtaining an interlayer insulating layer having a smooth surface and high adhesion to the conductor layer. 20-80 mass parts is preferable with respect to 100 mass parts of solid content of a resin composition, 30-70 mass parts is more preferable, and 40-60 mass parts is further more preferable.
The mass ratio [(J) / (H)] of the (J) epoxy resin and (H) cyanate resin in the resin composition for the adhesion auxiliary layer is an interlayer insulating layer having high adhesiveness to the conductor layer. From the viewpoint of obtaining, 0.5 to 5 is preferable, 1 to 3 is more preferable, and 1.2 to 2.5 is more preferable.

[(K) at least one selected from the group consisting of polyamide resin, polyimide resin and polybenzoxazole resin]
It is preferable that the resin composition for an adhesion auxiliary layer further contains at least one selected from the group consisting of (K) a polyamide resin, a polyimide resin, and a polybenzoxazole resin. Among these, it is preferable to contain a polyamide resin from the viewpoint of obtaining an interlayer insulating layer having a small surface roughness and excellent adhesion strength with a conductor layer formed by a plating method.

The polyamide resin used as the component (K) is a thermosetting resin (for example, an epoxy group of an epoxy resin) from the viewpoint of obtaining an interlayer insulating layer having a small surface roughness and excellent adhesion strength with a conductor layer formed by plating. Those containing a functional group (phenolic hydroxyl group, amino group, etc.) that reacts with the hydroxyl group are preferred, and those containing a phenolic hydroxyl group are more preferred. From the same viewpoint, the polyamide resin used as the component (K) preferably further contains a polybutadiene skeleton.
Such a polyamide resin is represented by the structural unit represented by the following general formula (7-1), the structural unit represented by the following general formula (7-2), and the following general formula (7-3). A phenolic hydroxyl group-containing polybutadiene-modified polyamide resin containing a structural unit is preferred.

In general formulas (7-1) to (7-3), a, b, c, x, y, and z are average polymerization degrees, respectively, a is 2 to 10, b is 0 to 3, and c is An integer of 3 to 30 is shown, y + z = 2 to 300 ((y + z) / x) with respect to x = 1, and z ≧ 20 (z / y) with respect to y = 1.
R ^K1 , R ^K2 and R ^K3 are each independently a divalent group derived from an aromatic diamine or an aliphatic diamine, and R ^K4 is an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid or a carboxy group at both ends. It is a divalent group derived from an oligomer having

Aromatic diamines used in the production of phenolic hydroxyl group-containing polybutadiene-modified polyamide resins include diaminobenzene, diaminotoluene, diaminophenol, diaminodimethylbenzene, diaminomesitylene, diaminonitrobenzene, diaminodiazobenzene, diaminonaphthalene, diaminobiphenyl, diaminodimethoxy. Biphenyl, diaminodiphenyl ether, diaminodimethyldiphenyl ether, methylenediamine, methylenebis (dimethylaniline), methylenebis (methoxyaniline), methylenebis (dimethoxyaniline), methylenebis (ethylaniline), methylenebis (diethylaniline), methylenebis (ethoxyaniline), methylenebis ( Diethoxyaniline), isopropylidenedianiline, Aminobenzophenone, diamino dimethyl benzophenone, diaminoanthraquinone, diaminodiphenyl thioether, diaminodiphenyl dimethyl diphenyl thioether, diaminodiphenyl sulfone, diaminodiphenyl sulfoxide, diaminofluorene and the like.
Aliphatic diamines used in the production of phenolic hydroxyl group-containing polybutadiene-modified polyamide resins include ethylenediamine, propanediamine, hydroxypropanediamine, butanediamine, heptanediamine, hexanediamine, diaminodiethylamine, diaminopropylamine, cyclopentanediamine, and cyclohexanediamine. , Azapentanediamine, triazaundecadiamine and the like. You may use these individually or in mixture of 2 or more types.

Examples of the phenolic hydroxyl group-containing dicarboxylic acid used in the production of the phenolic hydroxyl group-containing polybutadiene-modified polyamide resin include hydroxyisophthalic acid, hydroxyphthalic acid, hydroxyterephthalic acid, dihydroxyisophthalic acid, and dihydroxyterephthalic acid.
Examples of the dicarboxylic acid not containing a phenolic hydroxyl group used in the production of a phenolic hydroxyl group-containing polybutadiene-modified polyamide resin include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and oligomers having carboxy groups at both ends.
Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, biphenyl dicarboxylic acid, methylene dibenzoic acid, thiodibenzoic acid, carbonyl dibenzoic acid, sulfonylbenzoic acid, and naphthalenedicarboxylic acid.
Aliphatic dicarboxylic acids include oxalic acid, malonic acid, methylmalonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, malic acid, tartaric acid, (meth) acryloyloxysuccinic acid, di (meth) acryloyl Examples include oxysuccinic acid, (meth) acryloyloxymalic acid, (meth) acrylamide succinic acid, (meth) acrylamide malic acid, and the like. You may use these individually or in mixture of 2 or more types.

Commercially available products may be used as the phenolic hydroxyl group-containing polybutadiene-modified polyamide resin. Examples of commercially available products include polyamide resins “BPAM-01” and “BPAM-155” manufactured by Nippon Kayaku Co., Ltd.
As the polyamide resin, “BPAM-01” and “BPAM-155” are preferable from the viewpoint of obtaining an interlayer insulating layer having a small surface roughness and excellent adhesive strength with a conductor layer formed by plating, and “BPAM-155” is preferable. Is more preferable. “BPAM-155” is a rubber-modified polyamide resin having an amino group at the terminal and has reactivity with an epoxy group, and therefore an interlayer insulating layer obtained from a thermosetting resin composition containing “BPAM-155” Is more excellent in the adhesive strength with a conductor layer formed by plating, and the surface roughness tends to be small.

The number average molecular weight of the polyamide resin is preferably 20,000 to 30,000, more preferably 22,000 to 29,000, from the viewpoints of solubility in a solvent and film thickness retention of the adhesion assist layer after lamination. 24,000 to 28,000 are more preferable.
From the same viewpoint, the weight average molecular weight of the polyamide resin is preferably 100,000 to 140,000, more preferably 103,000 to 130,000, and further preferably 105,000 to 120,000.
The number average molecular weight and the weight average molecular weight were measured by gel permeation chromatography (GPC) (manufactured by Tosoh Corporation) using a standard polystyrene calibration curve, and details are described in Examples. It was measured according to the method.

  When the resin composition for an adhesion auxiliary layer contains a polyamide resin, the content is a resin composition for the adhesion auxiliary layer from the viewpoint of obtaining an interlayer insulating layer having a smooth surface and high adhesion to the conductor layer. 2-15 mass parts is preferable with respect to 100 mass parts of solid content, 4-13 mass parts is more preferable, 6-12 mass parts is further more preferable. When the content of the polyamide resin is 2 parts by mass or more, the adhesive strength with the conductor layer formed by the plating method tends to be excellent, and when it is 15 parts by mass or less, the interlayer insulating layer is roughened with an oxidizing agent. Furthermore, the surface roughness of the interlayer insulating layer tends to be suppressed, and the reflow heat resistance tends to be excellent.

[(L) Inorganic filler having a specific surface area of 20 to 500 m ² / g]
The resin composition for an adhesion auxiliary layer preferably further contains (L) an inorganic filler having a specific surface area of 20 to 500 m ² / g (hereinafter also simply referred to as “(L) inorganic filler”).
(L) The inorganic filler can prevent the resin from scattering and adjust the shape of the laser processing when laser processing the interlayer insulating layer formed by thermosetting the resin composition of the present invention. Important from the point of view. Further, when the surface of the interlayer insulating layer is roughened with an oxidizing agent, it is important from the viewpoint of forming an appropriate roughened surface and enabling formation of a conductor layer having excellent adhesive strength by plating. It is preferable to select from.

  (L) Inorganic fillers include silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate Strontium titanate, calcium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate and the like. Among these, silica is preferable from the viewpoint of obtaining excellent varnish handling properties and a low thermal expansion coefficient. (L) An inorganic filler may be used individually by 1 type, and may use 2 or more types together.

(L) The inorganic filler preferably has a small particle diameter from the viewpoint of forming fine wiring. From the same viewpoint, the specific surface area of (L) inorganic filler, a 20 to 500 m ² / g, preferably from ^{60~200m 2 / g, 90~130m 2 /} g is more preferable.
(L) The shape of the inorganic filler is an arbitrary shape. In particular, fumed silica, colloidal silica, etc., which will be described later, are not spherical, so that an appropriate roughened surface is formed, and a conductor layer having excellent adhesive strength is formed. In order to exhibit the effect, it is preferable to adjust the specific surface area to the above range.
The specific surface area can be determined by a BET method by low-temperature low-humidity physical adsorption of an inert gas such as nitrogen. Specifically, molecules having a known adsorption occupation area such as nitrogen are adsorbed on the surface of the powder particles at the liquid nitrogen temperature, and the specific surface area of the powder particles can be determined from the amount of adsorption.

(L) A commercially available product may be used as the inorganic filler. As the commercially available (L) inorganic filler, fumed silica “AEROSIL (Aerosil) (registered trademark) R972” (specific surface area 110 ± 20 m ² / g) and “AEROSIL (Aerosil) (registered trademark) R202” are used. (Specific surface area 100 ± 20 m ² / g) (Nippon Aerosil Co., Ltd.), colloidal silica “PL-1” (specific surface area 181 m ² / g) and “PL-7” (specific surface area 36 m ² / g) ) (Manufactured by Fuso Chemical Industry Co., Ltd.).
(L) The inorganic filler may be an inorganic filler surface-treated with a surface treatment agent such as a silane coupling agent in order to improve moisture resistance. The (L) inorganic filler is preferably one that is dissolved or uniformly dispersed in an organic solvent.

  When the resin composition for an adhesion auxiliary layer contains (L) an inorganic filler, the content is from the viewpoint of obtaining an interlayer insulating layer having a smooth surface and high adhesion to the conductor layer. 3 to 40 parts by weight is preferable, 5 to 30 parts by weight is more preferable, and 7 to 20 parts by weight is more preferable with respect to 100 parts by weight of the solid content of the resin composition. (L) When the content of the inorganic filler is 3 parts by mass or more, it is possible to prevent resin scattering during laser processing and to arrange the laser processing shape of the interlayer insulating layer, and when it is 40 parts by mass or less. High plating peel strength can be obtained.

[(M) Curing accelerator]
It is preferable that the resin composition for an adhesion auxiliary layer further contains (M) a curing accelerator.
(M) As a hardening accelerator, the same thing as said (G) hardening accelerator is mentioned. Among these, an organic phosphorus compound is preferable, and triphenylphosphine is more preferable.
When the adhesive auxiliary layer resin composition contains (M) a curing accelerator, the content varies depending on the type of (M) curing accelerator. When it contains, 0.001-1 mass part is preferable with respect to 100 mass parts of solid content of (A) epoxy resin, 0.002-0.1 mass part is more preferable, 0.003-0.05 mass Part is more preferred.

[Other ingredients]
The resin composition for an adhesion auxiliary layer may contain components other than the above components as long as the effects of the present invention are not impaired. Examples of the other components include the same components as the other components that may be contained in the interlayer insulating layer resin composition.

<The manufacturing method of the multilayer resin film which has an adhesion auxiliary layer>
As a method for producing a multilayer resin film having an adhesion auxiliary layer, for example, after coating a resin composition for an adhesion auxiliary layer in a varnish state on a support, it is dried to form an adhesion auxiliary layer on the support. A method of forming a resin composition layer for an interlayer insulating layer after forming the resin composition layer for an interlayer insulating layer in a varnish state after coating is provided on the adhesion auxiliary layer.
As another method, for example, an adhesion auxiliary layer is formed on a support by the above-described method, and a resin composition layer for an interlayer insulating layer is separately formed on a peelable film and formed on the support. The adhesion auxiliary layer and the resin composition layer for an interlayer insulating layer formed on the film are arranged such that the surface on which the adhesion auxiliary layer is formed and the surface on which the resin composition layer for the interlayer insulation layer is formed are in contact with each other. The method of laminating is also mentioned. In this case, the film which can peel the resin composition layer for interlayer insulation layers can also play a role as a protective film.

  The method for applying the resin composition for the adhesion auxiliary layer and the resin composition for the interlayer insulating layer and the drying conditions are the same as the method and conditions that can be used for producing the resin composition film for the interlayer insulating layer of the present invention. is there.

[Multilayer printed wiring board]
The multilayer printed wiring board of the present invention is obtained using at least one selected from the group consisting of the resin film for interlayer insulation layers and the multilayer resin film of the present invention. That is, the resin film for interlayer insulation layers of the present invention is useful for multilayer printed wiring boards. Furthermore, the resin film for interlayer insulation layers of the present invention is useful for forming a buildup layer of a multilayer printed wiring board, particularly a buildup wiring board.
The multilayer printed wiring board of the present invention has, for example, the following steps (1) to (6) [however, step (3) is arbitrary. ], And the support may be peeled off or removed after step (1), (2) or (3).
Hereinafter, when simply referred to as “resin film”, both “interlayer insulating layer resin film” and “multilayer resin film” are used.

(1) A step of laminating the resin film of the present invention on one or both sides of a circuit board [hereinafter referred to as laminating step (1)].
(2) A step of thermosetting the resin film laminated in step (1) to form an insulating layer [hereinafter referred to as insulating layer forming step (2)].
(3) A step of drilling the circuit board on which the insulating layer has been formed in the step (2) [hereinafter referred to as a drilling step (3)].
(4) A step of roughening the surface of the insulating layer with an oxidizing agent [hereinafter referred to as a roughening step (4)].
(5) A step of forming a conductor layer by plating on the surface of the roughened insulating layer [hereinafter referred to as a conductor layer forming step (5)].
(6) A step of forming a circuit on the conductor layer by a semi-additive method [hereinafter referred to as a circuit forming step (6)].

  The laminating step (1) is a step of laminating the resin film of the present invention on one or both sides of the circuit board using a vacuum laminator. Vacuum laminators include vacuum applicators manufactured by Nichigo-Morton Co., Ltd., vacuum press laminators manufactured by Meiki Seisakusho, roll-type dry coaters manufactured by Hitachi, Ltd., and vacuum laminators manufactured by Hitachi Chemical Electronics Co., Ltd. Can be mentioned.

When a protective film is provided on the resin film, after peeling or removing the protective film, the resin film for an interlayer insulating layer of the present invention is pressure-bonded to the circuit board while being pressed and heated so as to contact the circuit board. And can be laminated.
The laminate is prepared, for example, by preheating a resin film and a circuit board as necessary, and then a pressure bonding temperature of 60 to 140 ° C. and a pressure bonding pressure of 0.1 to 1.1 MPa (9.8 × 10 ^{4 to} 107.9 ×). 10 ⁴ N / m ² ) and an air pressure of 20 mmHg (26.7 hPa) or less. The laminating method may be a batch method or a continuous method using a roll.

In the insulating layer forming step (2), first, the resin film laminated on the circuit board in the laminating step (1) is cooled to around room temperature.
In the case of peeling the support, after peeling, the resin film laminated on the circuit board is heated and cured to form an insulating layer, that is, an insulating layer that later becomes an “interlayer insulating layer”. When using the multilayer resin film which has an adhesion auxiliary layer, the insulating layer formed here becomes a layer comprised from the hardened | cured material of the resin composition layer for interlayer insulation layers, and the hardened | cured material of an adhesion auxiliary layer.
The heat curing may be performed in two stages. For example, the first stage is 100 to 200 ° C. for 5 to 30 minutes, and the second stage is 140 to 220 ° C. for 20 to 80 minutes. . When a support subjected to a release treatment is used, the support may be peeled off after thermosetting.

  After forming an insulating layer by said method, you may pass through a drilling process (3) as needed. The drilling step (3) is a step of drilling the circuit board and the formed insulating layer by a method such as drill, laser, plasma, or a combination thereof to form a via hole, a through hole, or the like. As the laser, a carbon dioxide laser, YAG laser, UV laser, excimer laser, or the like is used.

In the roughening treatment step (4), the surface of the insulating layer is roughened with an oxidizing agent. Further, when via holes, through holes, and the like are formed in the insulating layer and the circuit board, so-called “smear” generated when these are formed may be removed by an oxidizing agent. Roughening and smear removal can be performed simultaneously.
Examples of the oxidizing agent include permanganate (potassium permanganate, sodium permanganate, etc.), dichromate, ozone, hydrogen peroxide, sulfuric acid, nitric acid and the like. Among these, an alkaline permanganate solution (for example, potassium permanganate, sodium permanganate hydroxide), which is an oxidizer widely used for roughening an insulating layer in the production of multilayer printed wiring boards by a build-up method. Sodium aqueous solution) can be used.
By roughening, irregular anchors are formed on the surface of the insulating layer.

In the conductor layer forming step (5), a conductor layer is formed by plating on the surface of the insulating layer that has been roughened and formed with uneven anchors.
Examples of the plating method include an electroless plating method and an electrolytic plating method. The metal for plating is not particularly limited as long as it can be used for plating. The metal for plating should be selected from copper, gold, silver, nickel, platinum, molybdenum, ruthenium, aluminum, tungsten, iron, titanium, chromium, or an alloy containing at least one of these metal elements. Copper and nickel are preferable, and copper is more preferable.
It is also possible to adopt a method in which a plating resist having a pattern opposite to that of the conductor layer (wiring pattern) is formed first, and then the conductor layer (wiring pattern) is formed only by electroless plating.
After forming the conductor layer, an annealing treatment may be performed at 150 to 200 ° C. for 20 to 120 minutes. By performing the annealing treatment, the adhesive strength between the interlayer insulating layer and the conductor layer tends to be further improved and stabilized. Further, the interlayer insulating layer may be cured by this annealing treatment.
In the circuit formation step (6), the conductor layer is patterned to form a circuit. Subtractive method, full additive method, semi-additive method (SAP: Semi-additive process), modified semi-additive method (m-SAP: modified) A known method such as Semi Additive Process can be used.

  The surface of the conductor layer thus produced may be roughened. By roughening the surface of the conductor layer, the adhesion with the resin in contact with the conductor layer tends to be improved. In order to roughen the conductor layer, organic acid micro-etching agents “CZ-8100”, “CZ-8101”, “CZ-5480” (all trade names, manufactured by MEC Co., Ltd.) and the like can be used. .

The circuit board used for the multilayer printed wiring board of the present invention was patterned on one or both sides of a substrate such as a glass epoxy, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, thermosetting polyphenylene ether substrate, etc. The thing in which the conductor layer (circuit) was formed is mentioned.
Moreover, the multilayer printed wiring board which has the conductor layer (circuit) by which the conductor layer and the insulating layer were alternately formed, and was patterned on the single side | surface or both surfaces, from the resin film of this invention on the single side | surface or both surfaces of the said circuit board Having a formed interlayer insulation layer, having a conductor layer (circuit) patterned on one or both sides thereof, a cured product formed by laminating and curing the resin film of the present invention (as a layer structure, adhesion An auxiliary layer, a resin composition layer for an interlayer insulating layer, a resin composition layer for an interlayer insulating layer, and a bonding auxiliary layer in this order) have a conductor layer (circuit) patterned on one or both sides of the present invention. In the circuit board.
From the viewpoint of adhesion of the interlayer insulating layer to the circuit board, the surface of the conductor layer of the circuit board may be subjected to a roughening process in advance by a blackening process or the like.

[1] Next, the first invention will be described in more detail with reference to examples. However, the first invention is not limited to these examples.

Example 1
As an epoxy resin, 25.8 parts by mass of “NC-3000-H” (manufactured by Nippon Kayaku Co., Ltd., trade name, solid content concentration: 100% by mass), which is a biphenyl novolac type epoxy resin,
6.3 parts by mass of “PAPS-PN2” (manufactured by Asahi Organic Materials Co., Ltd., trade name, solid content concentration: 100% by mass, Mw / Mn = 1.17) as a novolak type phenolic resin,
As an epoxy resin curing agent, 4.9 parts by mass of “LA-1356-60M” (trade name, solvent: MEK, solid content concentration 60% by mass, manufactured by DIC Corporation), which is a triazine-modified phenol novolac resin,
As an inorganic filler, the surface of “SO-C2” (manufactured by Admatechs Co., Ltd., trade name, average particle size: 0.5 μm) was treated with an aminosilane coupling agent, and further silica (solid) dispersed in MEK. 92.9 parts by mass of a partial concentration of 70% by mass)
As a curing accelerator, 0.026 parts by mass of “2E4MZ” (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name, solid content concentration: 100% by mass), which is 2-ethyl-4-methylimidazole,
As an additional solvent, 13.1 parts by mass of MEK was blended and subjected to mixing and bead mill dispersion treatment to prepare a resin composition varnish 1 for an adhesive film.
The resin composition varnish 1 for an adhesive film obtained above was applied onto a support film PET (manufactured by Teijin DuPont Films, trade name: G2, film thickness: 50 μm), and then dried to obtain a resin. A composition layer was formed. The coating thickness was 40 μm and drying was performed so that the residual solvent in the resin composition layer was 8.0% by mass. After drying, a polyethylene film (manufactured by Tamapoly Co., Ltd., trade name: NF-13, thickness: 25 μm) was laminated as a protective film on the resin composition layer surface side. Then, the obtained film was wound up in roll shape and the adhesive film 1 was obtained.

Examples 2 to 6, 8 and Comparative Examples 1 to 4
In Example 1, adhesive films 2 to 6 and 8 to 12 were obtained in the same manner as in Example 1 except that the raw material composition and production conditions were changed as described in Table 1.

Example 7
A resin varnish A produced by the following procedure was applied and dried on a support film PET (manufactured by Teijin DuPont Films, trade name: G2, film thickness: 50 μm) to a thickness of 10 μm. A support film 2 having a thickness of 60 μm was prepared.

The resin varnish A used above was produced by the following procedure.
As an epoxy resin, 63.9 parts by mass of “NC-3000-H” (manufactured by Nippon Kayaku Co., Ltd., trade name, solid content concentration: 100% by mass), which is a biphenyl novolac type epoxy resin,
As an epoxy resin curing agent, 18.0 parts by mass of “LA-1356-60M” (trade name, solvent; MEK, solid content concentration 60% by mass, manufactured by DIC Corporation), which is a triazine-modified phenol novolac resin,
15.2 parts by mass of “EXL-2655” (trade name, manufactured by Rohm and Haas Electronic Materials Co., Ltd.), which is a core-shell rubber particle,
As an inorganic filler, 8.8 parts by mass of fumed silica “Aerosil R972” (manufactured by Nippon Aerosil Co., Ltd., trade name, average particle size: 0.02 μm, solid content concentration: 100% by mass),
As a curing accelerator, 1.28 parts by mass of “2E4MZ” (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name, solid concentration 100% by mass), which is 2-ethyl-4-methylimidazole,
As an additional solvent, 226.1 parts by mass of cyclohexanone was blended and subjected to mixing and bead mill dispersion treatment to prepare a resin varnish A.
The resin varnish A obtained above was applied to PET (Teijin DuPont Films, trade name: G2, film thickness: 50 μm) as a support film so as to have a film thickness of 10 μm, and then dried. Thus, a support film 2 having a film thickness of 60 μm was obtained.

Next, the resin composition varnish for an adhesive film applied on the support film 2 obtained above was produced in the same manner as in Example 1 with the raw material composition and production conditions shown in Table 1.
The adhesive film 7 was obtained in the same manner as in Example 1 using the support film 2 and the resin composition varnish for adhesive film.

[Evaluation method]
The obtained adhesive films 1 to 12 were evaluated by the following methods.

(Preparation and test method for adhesive film handling test)
The obtained adhesive films 1 to 12 were cut into a size of 500 mm × 500 mm to prepare Samples 1 to 12 for handling property test of the adhesive film.
Using the samples 1 to 12 for handling test of the produced adhesive film, the handling properties were evaluated by the following methods (1) to (3). “Anything that was not defective in any of the tests was regarded as“ good handling ”.
(1) About the samples 1-12 for the handleability test of an adhesive film, the protective film was peeled first. When the protective film was peeled off, a part of the applied and dried resin that adhered to the protective film side or a powder that had fallen off was regarded as poor handleability.
(2) A film having two points at the center of the film (two points at the end so as to be 500 mm × 250 mm) and cracking occurred in the applied and dried resin was defined as poor handleability.
(3) "MCL-E-679FG (R)" which is a copper clad laminate obtained by blackening and reducing the surface copper foil (manufactured by Hitachi Chemical Co., Ltd., copper foil thickness 12 μm, plate thickness 0.41 mm) In addition, lamination was performed by lamination using a batch type vacuum pressure laminator “MVL-500” (trade name, manufactured by Meiki Seisakusho Co., Ltd.). The degree of vacuum at this time was 30 mmHg or less, the temperature was set to 90 ° C., and the pressure was set to 0.5 MPa. After cooling to room temperature, the support film was peeled off (the adhesive film 7 was peeled between PET and the resin layer formed thereon on the support film 2). In this case, a material in which powder falling off or PET was torn in the middle was regarded as poor handleability.

(Preparation and test method of thermal expansion coefficient measurement sample)
Each of the obtained adhesive films 1 to 12 was cut into a size of 200 mm × 200 mm, the protective film was peeled off, and a batch-type vacuum and pressure laminator “MVL-500” (Meiki Seisakusho Co., Ltd.) was applied to a 18 μm thick copper foil. And product name). The degree of vacuum at this time was 30 mmHg or less, the temperature was set to 90 ° C., and the pressure was set to 0.5 MPa.
After cooling to room temperature, the support film is peeled off (for the adhesive film 7, the support film 2 was peeled between PET and the resin layer formed thereon) and cured in a 180 ° C. drier for 120 minutes. did. Thereafter, the copper foil was removed with a ferric chloride solution, and the samples cut into a width of 3 mm and a length of 8 mm were designated as thermal expansion coefficient measurement samples 1 to 12.

The thermal expansion coefficient was measured by the following method using the produced samples 1 to 12 for measuring the thermal expansion coefficient.
Using the thermomechanical analyzer manufactured by Seiko Instruments Inc., the obtained samples 1 to 12 for measuring the thermal expansion coefficient were heated to 240 ° C. at a temperature rising rate of 10 ° C./min, cooled to −10 ° C. A change curve of the expansion amount when the temperature was raised to 300 ° C. at a temperature rate of 10 ° C./min was obtained, and an average coefficient of thermal expansion of 0 to 150 ° C. of the change curve of the expansion amount was obtained.

(Preparation and test method of embedding evaluation board)
The inner layer circuit used for the embedding evaluation board is as follows. “MCL-E-679FG (R)” (trade name, manufactured by Hitachi Chemical Co., Ltd.), which is a copper clad laminate having a copper foil thickness of 12 μm and a plate thickness of 0.15 mm (including the copper foil thickness), has a diameter of 0. A 15 mm through hole was produced by a drilling method so as to be a group of 25 × 25 at 5 mm intervals. Next, desmearing and electroless plating were performed, and electrolytic plating was performed in the through holes using electrolytic plating.
As a result, a circuit board having a plate thickness including copper thickness of 0.2 mm, a diameter of 0.1 mm, and 25 × 25 through holes at intervals of 5 mm was obtained.
Next, after arranging the adhesive films 1 to 12 with the protective film peeled off so that the resin composition layer faces the circuit surface side of the circuit board, the batch type vacuum laminator “MVL-500” (name machine Co., Ltd.) (Product name, manufactured by Seisakusho Co., Ltd.). The degree of vacuum at this time was 30 mmHg, the temperature was set to 90 ° C., and the pressure was set to 0.5 MPa.
After cooling to room temperature, a circuit board having through holes with adhesive films on both sides was sandwiched between two aluminum plates having a thickness of 1 mm, and lamination was performed using the vacuum laminator. The degree of vacuum at this time was 30 mmHg, the temperature was set to 90 ° C., and the pressure was set to 0.7 MPa.
After cooling to room temperature, the support film is peeled off (for the adhesive film 7, the support film 2 was peeled between PET and the resin layer formed thereon) and cured in a 180 ° C. drier for 120 minutes. did. Thus, embedding evaluation substrates 1 to 12 were obtained.

Using the fabricated embedding evaluation substrates 1 to 12, the embedding property was evaluated by the following method.
Using a contact-type surface roughness meter “SV2100” (trade name) manufactured by Mitutoyo Corporation, the steps on the surface of the through-hole portions of the embedding evaluation substrates 1 to 12 were measured. The level difference was measured so that 10 central portions of the surface of the through hole could enter, and the average value of the 10 dents was calculated.

The ingredients in Table 1 are shown below.
[Epoxy resin]
NC-3000-H: biphenyl novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name, solid content concentration 100% by mass)
N-673-80M: Cresol novolac type epoxy resin (manufactured by DIC Corporation, trade name, solvent; MEK, solid content concentration 80% by mass)
[Novolac type phenolic resin]
PAPS-PN2: novolak type phenol resin (Asahi Organic Materials Co., Ltd., trade name, solid content concentration 100% by mass, Mw / Mn = 1.17)
PAPS-PN3: Novolak type phenol resin (Asahi Organic Materials Co., Ltd., trade name, solid content concentration 100% by mass, Mw / Mn = 1.50)
HP-850: Novolac-type phenolic resin manufactured using hydrochloric acid instead of phosphoric acid (manufactured by Hitachi Chemical Co., Ltd., trade name, solid content concentration 100% by mass)
[Triazine-modified phenol novolac resin]
LA-1356-60M: triazine-modified phenol novolac resin (manufactured by DIC Corporation, trade name, solvent; MEK, solid content concentration 60 mass%)
[Inorganic filler]
SO-C2: Silica “SO-C2” (trade name, average particle size: 0.5 μm) manufactured by Admatechs Co., Ltd., treated with an aminosilane coupling agent and further dispersed in a MEK solvent (Solid concentration 70% by mass)
SO-C6: Silica “SO-C6” (trade name, average particle size: 2.2 μm) manufactured by Admatechs Co., Ltd., treated with an aminosilane coupling agent and further dispersed in a MEK solvent (Solid concentration 70% by mass)
Aerosil R972: fumed silica (manufactured by Nippon Aerosil Co., Ltd., trade name, solid content concentration 100% by mass, specific surface area: 100 m ² / g)
[Curing accelerator]
2E4MZ: 2-ethyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name, solid content concentration 100% by mass)

From Table 1, it can be seen that the adhesive film of the present invention has good handleability, and an interlayer insulating layer having a low thermal expansion coefficient and excellent embedding property can be obtained from the adhesive film of the present invention.
On the other hand, when the adhesive film of the present invention was not used, any of handleability, thermal expansion coefficient, and embeddability was inferior.
That is, according to the first invention, it can be seen that an adhesive film having a low thermal expansion coefficient, excellent embedding property, and excellent handleability can be provided, and an interlayer insulating layer having a low thermal expansion coefficient after curing can be provided.

[2] Next, the second invention will be described in more detail. However, the second invention is not limited to these examples.

The weight average molecular weight of the cyanate prepolymer, the weight average molecular weight and the number average molecular weight of the polyamide resin were determined by conversion from a calibration curve using standard polystyrene by gel permeation chromatography (GPC). The calibration curve was approximated by a cubic equation using standard polystyrene: TSKgel (SuperHZ2000, SuperHZ3000 [manufactured by Tosoh Corporation]). The GPC conditions are shown below.
・ Device: Pump: 880-PU [manufactured by JASCO Corporation]
RI detector: 830-RI [manufactured by JASCO Corporation]
Thermostatic bath: 860-CO [manufactured by JASCO Corporation]
Autosampler: AS-8020 [manufactured by Tosoh Corporation]
・ Eluent: Tetrahydrofuran ・ Sample concentration: 30 mg / 5 mL
・ Injection volume: 20μL
・ Flow rate: 1.00 mL / min ・ Measurement temperature: 40 ° C.

[Synthesis of cyanate prepolymer]
Production Example 1
(Synthesis of cyanate prepolymer A)
In a 5 L separable flask equipped with a Dean-Stark reflux condenser, a thermometer, and a stirrer, “Arocy (registered trademark) B-10”, a bisphenol A type bifunctional cyanate resin (manufactured by Huntsman, molecular weight 278) 35.8 g, 45.8 g of p- (α-cumyl) phenol (Mitsui Chemical Fine Co., Ltd., molecular weight 212) and 1,303 g of toluene were used as a reaction solution. The temperature of the reaction solution was raised and stirred until the temperature of the reaction solution reached 90 ° C. When the temperature reached 90 ° C., 2.799 g of zinc naphthenate (manufactured by Wako Pure Chemical Industries, Ltd., solid content concentration 8 mass%, mineral spirit solution cut product) was added to the reaction solution. Thereafter, the temperature was further raised to 110 ° C., and the mixture was stirred at 110 ° C. for 180 minutes. Subsequently, cyanate prepolymer A (weight average molecular weight: about 3,200) dissolved in toluene was prepared by additionally blending toluene so that the solid content concentration of the reaction solution was 70% by mass.

[Preparation of support auxiliary layer with support]
Production Example 2
The composition is blended according to the blending composition shown in Table 2 (the numerical values in the table are parts by mass of the solid content, and in the case of a solution (excluding organic solvents) or a dispersion, it is the solid content conversion amount)). Was dissolved until dissolved, and dispersed by bead milling to obtain a varnish-like resin composition for an adhesion auxiliary layer (solid content concentration: 20% by mass).
A PET film (NR-1, product name, manufactured by Teijin-DuPont Films Co., Ltd.) having a release treatment applied to one side which is a 38 μm-thick support, was obtained from the resin composition for an auxiliary adhesion layer obtained above. A die coater was used for coating on the release-treated surface, and drying was performed at 130 ° C. for 2 minutes to obtain an adhesion auxiliary layer with a support having a film thickness of 3 μm. The raw materials used are shown in Table 2.

  The materials used for blending the resin composition for the adhesion auxiliary layer are shown below.

[(H) cyanate resin]
Cyanate prepolymer A: cyanate prepolymer A synthesized in Production Example 1

[(J) Epoxy resin]
NC-3000-H: biphenylaralkyl structure-containing novolak type epoxy resin (“NC-3000-H” manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 289 g / eq, solid content concentration: 100 mass%)

[(K) Polyamide resin]
BPAM-155: Rubber-modified polyamide resin having an amino group at the terminal (“BPAM-155” manufactured by Nippon Kayaku Co., Ltd., number average molecular weight: 26,000, weight average molecular weight: 110,000, solid content concentration: 100% by mass ) Previously dissolved in dimethylacetamide so that the solid content concentration is 10% by mass.

[(L) Inorganic filler]
Aerosil R972: fumed silica (“Aerosil (registered trademark) R972” manufactured by Nippon Aerosil Co., Ltd., specific surface area: 100 m ² / g, solid content concentration: 100 mass%)

[(M) Curing accelerator]
・ Triphenylphosphine: (Tokyo Chemical Industry Co., Ltd., solid content concentration: 100% by mass)

[Production of Interlayer Insulating Layer Resin Film and Multilayer Resin Film]
(Reference) Example 1
The composition is blended according to the blending composition shown in Table 3 (the numerical values in the table are parts by mass of the solid content, and in the case of a solution (excluding organic solvents) or a dispersion, it is the solid content conversion amount)), and the bead mill treatment To obtain a varnish-like resin composition 1 for an interlayer insulating layer (solid content concentration: 71% by mass).
Next, the resin composition 1 for an interlayer insulating layer was separated from a PET film (NR-1, product name, manufactured by Teijin-DuPont Films Co., Ltd.) having a release treatment on one side having a thickness of 38 μm as a support. The resin film for interlayer insulation layers with a film thickness of 40 micrometers was obtained on PET film by apply | coating using a die-coater on a mold process surface, and making it dry at 100 degreeC for 1.5 minutes.
Moreover, the resin composition 1 for interlayer insulation layers obtained above was applied on the adhesion auxiliary layer of the adhesion auxiliary layer with a support obtained in Production Example 2 using a die coater, and 1. By drying for 5 minutes, a resin composition layer for an interlayer insulating layer having a film thickness of 37 μm was formed, and a multilayer resin film having an adhesion auxiliary layer was obtained.

(Reference) Examples 2-11, (Reference) Comparative Examples 1-3
(Reference) In Example 1, except that the composition of the resin composition for the interlayer insulating layer was changed to the composition shown in Table 3, (Reference) In the same manner as in Example 1, the resin film for the interlayer insulating layer and the adhesion auxiliary layer A multilayer resin film having was obtained.

[Evaluation method]
(1) Flame retardance Copper foil of a double-sided copper-clad laminate (manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-E-679F, 0.8 mm thickness) was removed by etching, and the both sides were obtained in each example. A resin film for an interlayer insulating layer was placed and laminated so that the resin surface faced the laminate, and then thermally cured at 190 ° C. for 120 minutes to prepare a test piece. About the obtained test piece, the flame retardance was evaluated according to the vertical combustion test (V method) based on UL-94 specification.

(2) Evaluation of the handleability of the resin film The resin film obtained in each example was allowed to stand at room temperature (25 ° C) for 5 days, and then bent to 180 ° with the resin surface on the outside (supported side inside). The presence or absence was confirmed visually. 20 sheets of interlayer insulating layer resin films were confirmed, and are shown in Table 3 as “number of cracked interlayer insulating layer resin films / 20”.

(3) Glass transition temperature (Tg) (Evaluation of heat resistance)
The glass transition temperature (Tg) was evaluated by preparing a sheet-like cured product from the resin film obtained in each example, and performing thermomechanical analysis (TMA) on the cured product.
A sheet-like cured product was produced by laminating resin films one by one by lamination to produce a laminate in which a total of five laminates were laminated, and the laminate was thermally cured at 190 ° C. for 180 minutes.
The cured product cut into a length of 40 mm (X direction), a width of 4 mm (Y direction), and a thickness of 80 mm (Z direction) is used as an evaluation substrate. The evaluation substrate is subjected to a thermomechanical analyzer (TA Instruments Inc.). Thermomechanical analysis was performed by the compression method using Q400). Specifically, after mounting the evaluation substrate on the apparatus in the pulling direction (xy direction), the measurement substrate is measured twice continuously under the measurement conditions of a load of 5 g and a temperature increase rate of 10 ° C./min. Tg indicated by the intersection of tangents with different thermal expansion curves in the measurement was obtained and used as an index of heat resistance. The results are shown in Table 3.

(4) Dissipation factor (Evaluation of electrical characteristics)
A sheet-like cured product was produced by the same method as the production method of the cured resin film used for evaluating the glass transition temperature, and the cured product was cut into a length of 70 mm and a width of 2 mm as an evaluation sample. . The dielectric loss tangent of this evaluation sample was measured at a measurement frequency of 5 GHz and a measurement temperature of 23 ° C. by a cavity resonance perturbation method using “HP8362B” manufactured by Agilent Technologies. The results are shown in Table 3.

(5) Surface Roughness In measuring the surface roughness, a surface roughness measuring substrate was prepared according to the following procedure.
Double-sided copper-clad laminate (trade name: MCL-E-679F, 0.8 mm thickness) manufactured by Hitachi Chemical Co., Ltd. is roughened by etching 1 μm using an etching agent “CZ8101” (trade name) manufactured by MEC Co., Ltd. After the treatment, the multilayer resin film having the adhesion auxiliary layer obtained in each example was disposed on both surfaces thereof and laminated so that the resin surface opposed to the laminate. Thereafter, the support film was thermally cured at 190 ° C. for 60 minutes with the support film attached, and the support film was peeled off. The obtained sample was cut into a length of 60 mm (X direction) and a width of 120 mm (Y direction) as a test piece, and the swelling solution “CIRCUPOSIT MLB CONDITIONER 211” (Rohm and Immersion for 3 minutes. Next, it was immersed for 8 minutes in a roughing solution “CIRCUPOSIT MLB PROMOTER 213” (manufactured by Rohm and Haas Electronic Materials) heated to 80 ° C. Subsequently, the mixture was neutralized by immersion for 5 minutes in a neutralizing solution “CIRCUPOSIT MLB NEUTALIZER MLB216” (manufactured by Rohm and Haas Electronic Materials) heated to 45 ° C. In this way, a surface roughness measuring substrate whose surface was roughened was obtained.
About the obtained surface roughness measurement substrate, using a specific contact type surface roughness meter “WykoNT9100” (trade name, manufactured by Bruker AXS Co., Ltd.), using an internal lens 1 × and an external lens 50 ×, The surface roughness of the adhesion auxiliary layer was measured to obtain the arithmetic average roughness (Ra). Arithmetic average roughness (Ra) is an average value obtained by measuring the average roughness at five locations for an arbitrary portion in the substrate for surface roughness measurement (however, a region where via holes are not formed by laser). . The results are shown in Table 3. The arithmetic average roughness (Ra) is preferably as small as possible from the gist of the present invention.

  It shows below about each component of Table 3.

[(A) Epoxy resin]
N-673: Cresol novolac type epoxy resin (“Epiclon (registered trademark) N-673” manufactured by DIC Corporation, epoxy equivalent: 210 g / eq, solid content concentration: 100 mass%)
JER157S70: Bisphenol A novolak type epoxy resin (“jER (registered trademark) 157S70” manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: 210 g / eq, solid content concentration: 100 mass%)
JER828: Liquid epoxy resin of bisphenol A type (“jER (registered trademark) 828” manufactured by Mitsubishi Chemical Corporation, solid content concentration: 100 mass%, epoxy equivalent: 185 g / eq)

[(B) Cyanate resin]
Cyanate prepolymer A: cyanate prepolymer A synthesized in Production Example 1
BA3000S: Prepolymer of bisphenol A type cyanate resin ("Primaset BA3000S" manufactured by Lonza)

[(C) Inorganic filler]
Aminosilane coupling agent treatment SO-C2: Spherical silica “SO-C2” (manufactured by Admatechs Co., Ltd., average particle size: 0) treated with an aminosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM573) .5 μm) in a MEK solvent so that the solid concentration is 70 mass%.

[(D) Phosphorus-containing compound]
PX-200: 1,3-phenylene-bis (di-2,6-dimethylphenyl phosphate) (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 9% by mass, compound represented by the general formula (1) )
CR-741: Bisphenol A bis (diphenyl phosphate) (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 8.9% by mass, compound represented by general formula (1))
PX-201: 1,4-phenylene-bis (di-2,6-dimethylphenyl phosphate) (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 9% by mass, compound represented by the general formula (1) )
PX-202: 4,4′-biphenylene-bis (di-2,6-dimethylphenyl phosphate) (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 8.1% by mass, represented by general formula (1) Compound)
TPP: Triphenyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 9.5% by mass)
TCP: tricresyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 8.4% by mass)
TXP: Trixylenyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., phosphorus content: 7.6% by mass)
SPB100: Phenoxyphosphazene (manufactured by Otsuka Chemical Co., Ltd., phosphorus content: 13% by mass, compound represented by general formula (2))

[(D ′) Phosphorus-containing Compound (Comparative Component)]
・ HCA-HQ-HS: 10- (2,5-dihydroxyphenyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (manufactured by Sanko Co., Ltd.)
-OP-930: Polyphosphate compound (manufactured by Clariant Japan KK, phosphorus content: 23% by mass, average particle size; about 5 μm)

[(E) Phenoxy resin]
YX7200B35: phenoxy resin (“jER (registered trademark) YX7200B35” manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: 3,000 to 16,000 g / eq, solid content concentration 35 mass%, MEK cut)

[(F) Active ester curing agent]
-HPC-8000-65T: Active ester resin (“EPICLON (registered trademark) HPC-8000-65T” manufactured by DIC Corporation, solid content concentration 65 mass%, toluene cut product)

[(G) Curing accelerator]
・ Triphenylphosphine (Kanto Chemical Co., Ltd.)
・ Zinc naphthenate: (Wako Pure Chemical Industries, Ltd., solid content concentration 8 mass%, mineral spirit solution)
Curing accelerator 1: addition reaction product of tributylphosphine and 1,4-benzoquinone represented by the following formula (G-7) synthesized with reference to JP 2011-179008 A (solid content concentration: 100% by mass)

From the results in Table 3, (reference) the interlayer insulating layer formed by the resin film for interlayer insulating layer obtained in Examples 1 to 11 is excellent in flame retardancy, has a high glass transition temperature, and has a low dielectric loss tangent. Furthermore, the handleability of the resin film was also excellent. That is, it can be seen that the resin film for an interlayer insulating layer of the present invention is excellent in handleability, and the interlayer insulating layer formed by the resin film for an interlayer insulating layer of the present invention is excellent in electrical characteristics, heat resistance and flame retardancy. .
On the other hand, (D) the resin film for an interlayer insulating layer of Comparative Example 1 containing no phosphorus-containing compound (reference) was inferior in flame retardancy. Further, in Comparative Examples 2 and 3, which contains a phosphorus-containing compound (D ′) different from at least one selected from the group consisting of cyclic phosphazene, aromatic phosphate ester and aromatic condensed phosphate ester (reference) In (Reference) Comparative Example 2, the handleability of the resin film was poor, and (Reference) Comparative Example 3 was inferior in surface roughness.

Claims (1)

(A) a novolak-type phenol resin having a dispersion ratio (Mw / Mn) of a weight average molecular weight (Mw) and a number average molecular weight (Mn) of 1.05 to 1.8;
(B) an epoxy resin represented by the following general formula (I);
(C) an inorganic filler;
A resin composition layer formed by layering a resin composition containing
The average particle diameter of (c) inorganic filler in the resin composition layer is 0.1 μm or more,
(C) The adhesive film for multilayer printed wiring boards whose content of an inorganic filler is 20-95 mass% among resin solid content.

(In the formula, p represents an integer of 1 to 5.)