JP2021181557A - Resin composition - Google Patents

Abstract

To provide a resin composition that can give a cured product having a low dielectric constant.SOLUTION: The inventive resin composition contains bubbles.SELECTED DRAWING: None

Description

The present invention relates to a resin composition. Further, the present invention relates to a resin sheet, a printed wiring board, and a semiconductor device formed by using the resin composition, and a method for manufacturing the resin composition and a method for manufacturing the printed wiring board.

As a manufacturing technique for a printed wiring board, a manufacturing method by a build-up method in which an insulating layer and a conductor layer are alternately stacked on an inner circuit board is known. The insulating layer is generally formed by curing the resin composition.

For example, Patent Document 1 describes a resin composition containing a liquid epoxy resin, a solid epoxy resin, an active ester curing agent, and an inorganic filler. On the other hand, Patent Document 2 describes a technique using microbubbles.

Japanese Unexamined Patent Publication No. 2020-029494 Japanese Unexamined Patent Publication No. 2016-056317

By the way, in recent years, in the production of a multilayer printed wiring board, a cured product of a resin composition for forming an insulating layer is required to have a lower dielectric constant.

The subject of the present invention is a resin composition capable of obtaining a cured product having a low dielectric constant; a resin sheet obtained by using the resin composition; a printed wiring board; a semiconductor device; a method for producing a resin composition; and a printed wiring. The purpose is to provide a method for manufacturing a board.

As a result of diligent studies to solve the above-mentioned problems, the present inventor has found that the above-mentioned problems can be solved by containing bubbles in the resin composition, and has completed the present invention.
That is, the present invention includes the following contents.

[1] A resin composition containing bubbles.
[2] The resin composition according to [1], wherein the average particle size of the bubbles is 50 μm or less.
[3] The resin composition according to [1] or [2], wherein the bubbles are microbubbles.
[4] The resin composition according to any one of [1] to [3], which contains a liquid epoxy resin.
[5] The resin composition according to [4], wherein the content of the liquid epoxy resin is 1% by mass or more and 30% by mass or less when the non-volatile component in the resin composition is 100% by mass.
[6] The resin composition according to [4] or [5], wherein the liquid epoxy resin has a viscosity at 25 ° C. of 300 mPa · s or more and 5000 mPa · s or less.
[7] The resin composition according to any one of [1] to [6], which contains an inorganic filler.
[8] The resin composition according to [7], wherein the content of the inorganic filler is 20% by mass or more when the non-volatile component in the resin composition is 100% by mass.
[9] The resin composition according to any one of [1] to [8], which is used for forming an insulating layer.
[10] The resin composition according to any one of [1] to [9], which is used for forming an insulating layer for forming a conductor layer.
[11] A resin sheet comprising a support and a resin composition layer provided on the support and containing the resin composition according to any one of [1] to [10].
[12] A printed wiring board including an insulating layer formed of a cured product of the resin composition according to any one of [1] to [10].
[13] A semiconductor device including the printed wiring board according to [12].
[14] (a) A method for producing a resin composition, which comprises a step of dispersing bubbles in a resin component having a viscosity at 25 ° C. of 300 mPa · s or more and 5000 mPa · s or less.
[15] The method for producing a resin composition according to [14], wherein the resin component contains a liquid epoxy resin.
[16] The method for producing a resin composition according to [14] or [15], wherein the bubble ratio of bubbles in the resin component is 30% by volume or more and 90% by volume or less.
[17] (I) A step of forming a resin composition layer containing the resin composition according to any one of [1] to [10] on the inner layer substrate, and (II) thermosetting the resin composition layer. A method for manufacturing a printed wiring board, which includes a step of forming an insulating layer.

According to the present invention, a resin composition capable of obtaining a cured product having a low dielectric constant; a resin sheet obtained by using the resin composition; a printed wiring board; a semiconductor device; a method for producing a resin composition; and a printed wiring. It has become possible to provide a method for manufacturing a board.

Hereinafter, the resin composition of the present invention; the resin sheet obtained by using the resin composition; the printed wiring board; the semiconductor device; the method for producing the resin composition; and the method for producing the printed wiring board will be described in detail.

[Resin composition]
The resin composition of the present invention contains bubbles. By containing bubbles in the resin composition, it is possible to obtain a cured product having a low dielectric constant. Further, in the present invention, a cured product having excellent insulation reliability, mechanical strength, glass transition temperature (Tg), and coefficient of linear thermal expansion (CTE) and having bubbles for a long time (excellent in process suitability) is usually obtained. Is possible. In general, it has been said that the presence of air bubbles (voids) in the resin composition adversely affects the electrical characteristics and the like of the cured product of the resin composition. Therefore, it has been considered preferable that the resin composition does not contain air bubbles. However, in the present invention, it is possible to obtain a cured product having a low dielectric constant by containing bubbles in the resin composition. Further, by adjusting the average particle size of the bubbles, it is possible to obtain a cured product having excellent insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient. As far as the present inventor knows, it can be said that the technical idea of intentionally containing bubbles in the resin composition has not been proposed in the past.

The average particle size of the bubbles is preferably 60 μm or less, more preferably 50 μm or less, from the viewpoint of obtaining a cured product having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient. More preferably, it is 45 μm, 40 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, or 5 μm or less. Further, the lower limit is preferably 0.01 μm or more, more preferably 0.1 μm or more, still more preferably 0.5 μm or more, and 1 μm or more from the viewpoint of remarkably obtaining the effect of the present invention. The average particle size of the bubbles can be measured according to the method described in Examples described later. In addition, bubbles having an average particle size in the above range are less likely to collect and aggregate in the resin composition and are less likely to be discharged from the resin composition. Therefore, since the bubbles are stable, a cured product having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient can be easily produced. Further, the smaller the average particle size of the bubbles, the more remarkable the effect of the present invention can be obtained.

The standard deviation of the average particle size of the bubbles is preferably 25 μm or less, more preferably 20 μm or less, still more preferably 15 μm or less, from the viewpoint of remarkably obtaining the effect of the present invention. The lower limit is not particularly limited, but can usually be 0.1 μm or more.

The bubbles may be any bubbles as long as they can obtain a cured product having a low dielectric constant, and examples thereof include microbubbles, nanobubbles, and ultrafine bubbles. In addition, when these bubbles are used, insulation reliability, mechanical strength, glass transition temperature (Tg), and coefficient of linear thermal expansion can usually be improved. As used herein, the term "microbubbles" refers to microbubbles having a diameter of 1 μm or more and 60 μm or less. The smaller the average particle size of the microbubbles, the more remarkable the effect of the present invention can be obtained.

Examples of the gas component constituting the bubbles include those capable of obtaining a cured product having a low dielectric constant, and examples thereof include air; rare gases such as helium, neon, and argon; oxygen; nitrogen; carbon dioxide and the like. , Air is preferable from the viewpoint of remarkably obtaining the effect of the present invention. Further, when the gas component constituting the bubble is the above-mentioned one, the insulation reliability, the mechanical strength, the glass transition temperature (Tg), and the coefficient of linear thermal expansion can usually be improved.

The content of bubbles in the resin composition is a non-volatile component in the resin composition from the viewpoint of obtaining a cured product having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient. When it is 100% by volume, it is preferably 1% by volume or more, more preferably 3% by volume or more, further preferably 5% by volume or more, 8% by volume or more, 10% by volume or more, 30% by volume or more, and 50% by volume or more. It is preferably 95% by volume or less, more preferably 90% by volume or less, and particularly preferably 85% by volume or less. The content of the bubbles can be calculated from the specific gravity of the resin composition before containing the bubbles and the specific gravity of the resin composition after containing the bubbles, assuming that the mass of the bubbles themselves is negligibly light.

The content of bubbles (bubble content) contained in the cured product of the resin composition is preferably 3% by volume or more, more preferably 5% by volume or more, still more preferably 10% by volume or more. The upper limit is not particularly limited, but may be 50% by volume or less. The bubble content of the cured product of the resin composition can be measured according to the method described in Examples described later.

It is preferable that the cured product of the resin composition has sufficient hardness and insulating properties. Therefore, it is preferable that the resin composition contains, for example, a curable resin in addition to the bubbles. As the curable resin, a conventionally known curable resin used for forming an insulating layer of a printed wiring board can be used, and among them, an epoxy resin and a curing agent are preferable. Therefore, in one embodiment, the resin composition preferably contains (A) an epoxy resin and (B) a curing agent. Further, the resin composition further includes (C) an inorganic filler, (D) a curing accelerator, (E) a thermoplastic resin, (F) a radically polymerizable resin, (G) a polymerization initiator, and (H) a flame retardant. And (I) other additives may be included. Hereinafter, each component that can be contained in the resin composition will be described in detail.

<(A) Epoxy resin>
The resin composition may contain (A) an epoxy resin as the component (A). Examples of the component (A) include bixilenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, and trisphenol type epoxy. Resin, naphthol novolac type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, Cresol novolak type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin having a butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spiro ring-containing epoxy resin, cyclohexane type epoxy resin, cyclohexanedi Examples thereof include a methanol type epoxy resin, a naphthylene ether type epoxy resin, a trimethylol type epoxy resin, and a tetraphenylethane type epoxy resin. The component (A) may be used alone or in combination of two or more.

The resin composition preferably contains an epoxy resin having two or more epoxy groups in one molecule as the component (A). From the viewpoint of remarkably obtaining the desired effect of the present invention, the ratio of the epoxy resin having two or more epoxy groups in one molecule is preferably 20% by mass with respect to 100% by mass of the non-volatile component of the component (A). As mentioned above, it is more preferably 30% by mass or more, and particularly preferably 40% by mass or more.

The epoxy resin may be a liquid epoxy resin at a temperature of 20 ° C. (hereinafter sometimes referred to as “liquid epoxy resin”) or a solid epoxy resin at a temperature of 20 ° C. (hereinafter referred to as “solid epoxy resin”). ). The resin composition may contain only the liquid epoxy resin as the component (A), may contain only the solid epoxy resin, or may contain a combination of the liquid epoxy resin and the solid epoxy resin. However, from the viewpoint of remarkably obtaining the desired effect of the present invention, it is preferable to include the liquid epoxy resin and the solid epoxy resin in combination.

As the liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferable.

Examples of the liquid epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenol novolac type epoxy resin, and ester skeleton. An alicyclic epoxy resin, a cyclohexane type epoxy resin, a cyclohexanedimethanol type epoxy resin, a glycidylamine type epoxy resin, and an epoxy resin having a butadiene structure are preferable, and a naphthalene type epoxy resin is more preferable.

Specific examples of the liquid epoxy resin include "HP4032", "HP4032D" and "HP4032SS" (naphthalene type epoxy resin) manufactured by DIC; "828US", "jER828EL", "825" and "Epicoat" manufactured by Mitsubishi Chemical Co., Ltd. 828EL "(bisphenol A type epoxy resin);" jER807 "," 1750 "(bisphenol F type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd .;" jER152 "(phenol novolak type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "630", "630LSD" (glycidylamine type epoxy resin); "ZX1059" (mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nittetsu Chemical & Materials Co., Ltd .; "EX-721" (glycidyl ester type epoxy resin); "Selokiside 2021P" manufactured by Daicel Co., Ltd. (alicyclic epoxy resin having an ester skeleton); "PB-3600" manufactured by Daicel Co., Ltd. (epoxy resin having a butadiene structure) Examples thereof include "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin) manufactured by Nittetsu Chemical & Materials Co., Ltd. These may be used individually by 1 type, or may be used in combination of 2 or more types.

The viscosity of the liquid epoxy resin at 25 ° C. is preferably 300 mPa · s or more, more preferably 500 mPa · s or more, still more preferably 1000 mPa · s or more, from the viewpoint of allowing bubbles to stably exist in the resin composition. It is preferably 5000 mPa · s or less, more preferably 4000 mPa · s or less, and further preferably 3000 mPa · s or less. The viscosity of the liquid epoxy resin can be measured using, for example, an E-type viscometer.

As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in one molecule is preferable, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is more preferable.

Examples of the solid epoxy resin include bixilenol type epoxy resin, naphthalene type epoxy resin, naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, and biphenyl. Type epoxy resin, naphthylene ether type epoxy resin, anthracene type epoxy resin, bisphenol A type epoxy resin, bisphenol AF type epoxy resin, tetraphenylethane type epoxy resin are preferable, and naphthol type epoxy resin is more preferable.

Specific examples of the solid epoxy resin include "HP4032H" (naphthalene type epoxy resin) manufactured by DIC; "HP-4700" and "HP-4710" (naphthalen type tetrafunctional epoxy resin) manufactured by DIC; DIC. "N-690" (cresol novolac type epoxy resin); DIC "N-695" (cresol novolac type epoxy resin); DIC "HP-7200", "HP-7200HH", "HP" -7200H "(dicyclopentadiene type epoxy resin);" EXA-7311 "," EXA-7311-G3 "," EXA-7311-G4 "," EXA-7311-G4S "," HP6000 "(HP6000) manufactured by DIC. Naftylene ether type epoxy resin); "EPPN-502H" (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd .; "NC7000L" (naphthol novolac type epoxy resin) manufactured by Nihon Kayaku Co., Ltd .; "NC3000H", "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin); "ESN475V" (naphthol type epoxy resin) manufactured by Nittetsu Chemical & Materials Co., Ltd .; "ESN485" manufactured by Nittetsu Chemical & Materials Co., Ltd. (Naftor Novolak type epoxy resin); "YX4000H", "YX4000", "YL6121" (biphenyl type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd .; "YX4000HK" (bixilenol type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YX8800" (anthracene type epoxy resin) manufactured by Osaka Gas Chemical Co., Ltd .; "PG-100" and "CG-500" manufactured by Osaka Gas Chemical Co., Ltd .; "YL7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd. "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd .; "jER1010" (solid bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd .; "jER1031S" (tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd. and the like can be mentioned. .. These may be used individually by 1 type, or may be used in combination of 2 or more types.

When a liquid epoxy resin and a solid epoxy resin are used in combination as the component (A), the amount ratio (liquid epoxy resin: solid epoxy resin) thereof is a mass ratio, preferably 1: 1 to 1:20. It is more preferably 1: 1.5 to 1:15, and particularly preferably 1: 2 to 1:10. When the quantitative ratio of the liquid epoxy resin and the solid epoxy resin is in such a range, the desired effect of the present invention can be remarkably obtained. Further, usually, when used in the form of a resin sheet, moderate adhesiveness is provided. Further, when used in the form of a resin sheet, sufficient flexibility is usually obtained and handleability is improved. Further, usually, a cured product having sufficient breaking strength can be obtained.

The epoxy equivalent of the component (A) is preferably 50 g / eq. ~ 5000 g / eq. , More preferably 50 g / eq. ~ 3000 g / eq. , More preferably 80 g / eq. ~ 2000 g / eq. , Even more preferably 110 g / eq. ~ 1000 g / eq. Is. Within this range, the crosslink density of the cured product of the resin composition layer becomes sufficient, and an insulating layer having a small surface roughness can be obtained. The epoxy equivalent is the mass of the epoxy resin containing one equivalent of the epoxy group. This epoxy equivalent can be measured according to JIS K7236.

The weight average molecular weight (Mw) of the component (A) is preferably 100 to 5000, more preferably 200 to 3000, still more preferably 250 to 1500, from the viewpoint of remarkably obtaining the desired effect of the present invention.
The weight average molecular weight of the resin can be measured as a polystyrene-equivalent value by a gel permeation chromatography (GPC) method.

The content of the component (A) is preferably 1% by mass or more when the non-volatile component in the resin composition is 100% by mass from the viewpoint of obtaining an insulating layer showing good mechanical strength and insulation reliability. It is preferably 5% by mass or more, more preferably 10% by mass or more. The upper limit of the content of the epoxy resin is preferably 25% by mass or less, more preferably 20% by mass or less, and particularly preferably 15% by mass or less, from the viewpoint of remarkably obtaining the desired effect of the present invention.
In the present invention, the content of each component in the resin composition is a value when the non-volatile component in the resin composition is 100% by mass, unless otherwise specified.

The content of the liquid epoxy resin is preferably 1% by mass or more, more preferably 3% by mass or more, when the non-volatile component in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the effect of the present invention. It is more preferably 5% by mass or more, preferably 30% by mass or less, more preferably 20% by mass or less, still more preferably 10% by mass or less.

<(B) Curing agent>
The resin composition may further contain (B) a curing agent as an arbitrary component. The component (B) usually has a function of reacting with the component (A) to cure the resin composition. As the component (B), one type may be used alone, or two or more types may be used in combination at any ratio.

As the component (B), a compound capable of reacting with the component (A) to cure the resin composition can be used, for example, an active ester-based curing agent, a phenol-based curing agent, a benzoxazine-based curing agent, and the like. Examples thereof include a carbodiimide-based curing agent, an acid anhydride-based curing agent, an amine-based curing agent, and a cyanate ester-based curing agent. Among them, any of an active ester-based curing agent, a phenol-based curing agent, a benzoxazine-based curing agent, and a carbodiimide-based curing agent is preferable from the viewpoint of remarkably obtaining the effect of the present invention, and the active ester-based curing agent and the phenol-based curing agent are preferable. , And any of the carbodiimide-based curing agents are more preferable.

Examples of the active ester-based curing agent include curing agents having one or more active ester groups in one molecule. Among them, as the active ester-based curing agent, two or more ester groups having high reaction activity such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds are contained in one molecule. The compound to have is preferable. The active ester-based curing agent is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester-based curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester-based curing agent obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound is more preferable. ..

Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid and the like.

Examples of the phenol compound or naphthol compound 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, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenol, trihydroxybenzophenone, tetrahydroxybenzophenone, fluoroglucin, Examples thereof include benzenetriol, dicyclopentadiene-type diphenol compound, and phenol novolac. Here, the "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing two phenol molecules with one dicyclopentadiene molecule.

Preferred specific examples of the active ester-based curing agent include an active ester compound containing a dicyclopentadiene-type diphenol structure, an active ester compound containing a naphthalene structure, an active ester compound containing an acetylated product of phenol novolac, and a benzoyl compound of phenol novolac. Examples include active ester compounds containing. Of these, an active ester compound containing a naphthalene structure and an active ester compound containing a dicyclopentadiene-type diphenol structure are more preferable. The "dicyclopentadiene-type diphenol structure" represents a divalent structure composed of phenylene-dicyclopentylene-phenylene.

Commercially available products of active ester-based curing agents include "EXB9451", "EXB9460", "EXB9460S", "HPC-8000", "HPC-8000H", and "EXB9451", "EXB9460", "EXB9460S", and "HPC-8000H", as active ester compounds containing a dicyclopentadiene type diphenol structure. HPC-8000-65T "," HPC-8000H-65TM "," EXB-8000L "," EXB-8000L-65TM "(manufactured by DIC);" HPC-8150-60T "as an active ester compound containing a naphthalene structure, "HPC-8150-62T", "EXB-8150-65T", "EXB-8100L-65T", "EXB-8150L-65T", "EXB9416-70BK" (manufactured by DIC); "DC808" as an active ester compound (manufactured by Mitsubishi Chemical Co., Ltd.); "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.) as an active ester compound containing a benzoyl compound of phenol novolac; "DC808" as an active ester-based curing agent which is an acetylated product of phenol novolac. (Manufactured by Mitsubishi Chemical Co., Ltd.); "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.), "YLH1030" (manufactured by Mitsubishi Chemical Co., Ltd.), "YLH1048" (manufactured by Mitsubishi Chemical Co., Ltd.) as active ester-based curing agents that are benzoyl compounds of phenol novolac. ; Etc. can be mentioned.

Examples of the phenolic curing agent include a curing agent having one or more, preferably two or more hydroxyl groups bonded to an aromatic ring (benzene ring, naphthalene ring, etc.) in one molecule. Of these, a compound having a hydroxyl group bonded to a benzene ring is preferable. Further, from the viewpoint of heat resistance and water resistance, a phenol-based curing agent having a novolak structure is preferable. Further, from the viewpoint of adhesion, a nitrogen-containing phenol-based curing agent is preferable, and a triazine skeleton-containing phenol-based curing agent is more preferable. In particular, a triazine skeleton-containing phenol novolac curing agent is preferable from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion.

Specific examples of the phenol-based curing agent and the naphthol-based curing agent include "MEH-7700", "MEH-7810", "MEH-7851", and "MEH-8000H" manufactured by Meiwa Kasei Co., Ltd .; manufactured by Nippon Kayaku Co., Ltd. "NHN", "CBN", "GPH"; "SN-170", "SN-180", "SN-190", "SN-475", "SN-485" manufactured by Nittetsu Chemical & Materials Co., Ltd. "SN-495", "SN-495V", "SN-375", "SN-395"; "TD-2090", "TD-2090-60M", "LA-7052", "LA" manufactured by DIC Corporation. -7054 "," LA-1356 "," LA-3018 "," LA-3018-50P "," EXB-9500 "," HPC-9500 "," KA-1160 "," KA-1163 "," KA " -1165 ";" GDP-6115L "," GDP-6115H "," ELPC75 "manufactured by Gunei Chemical Corporation and the like can be mentioned.

Specific examples of the benzoxazine-based curing agent include "ODA-BOZ" manufactured by JFE Chemical Co., Ltd., "HFB2006M" manufactured by Showa High Polymer Co., Ltd., and "P-d" and "FA" manufactured by Shikoku Chemicals Corporation. Can be mentioned.

Specific examples of the carbodiimide-based curing agent include "V-03", "V-05", and "V-07" manufactured by Nisshinbo Chemical Co., Ltd .; Stavaxol (registered trademark) P manufactured by Rheinchemy Co., Ltd. and the like.

Examples of the acid anhydride-based curing agent include a curing agent having one or more acid anhydride groups in one molecule. Specific examples of the acid anhydride-based curing agent include phthalic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methylnagic. Acid Anhydride, Methylnadic Acid Anhydride, TrialkyltetrahydroAnhydrous Phthrate, Dodecenyl Anhydrous Succinic Acid, 5- (2,5-Dioxotetrahydro-3-Franyl) -3-Methyl-3-Cyclohexene-1, 2-Dicarboxylic acid anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic acid dianhydride, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 3 , 3'-4,4'-diphenylsulfone tetracarboxylic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-franyl) -naphtho [ 1,2-C] Fran-1,3-dione, ethylene glycol bis (anhydrotrimethylate), polymer-type acid anhydrides such as styrene / maleic acid resin in which styrene and maleic acid are copolymerized. Be done. As the acid anhydride-based curing agent, a commercially available product may be used, and examples thereof include "MH-700" manufactured by Shin Nihon Rika Co., Ltd.

Examples of the amine-based curing agent include curing agents having one or more amino groups in one molecule, and examples thereof include aliphatic amines, polyether amines, alicyclic amines, and aromatic amines. Among them, aromatic amines are preferable from the viewpoint of achieving the desired effect of the present invention. The amine-based curing agent is preferably a primary amine or a secondary amine, more preferably a primary amine. Specific examples of the amine-based curing agent include 4,4'-methylenebis (2,6-dimethylaniline), diphenyldiaminosulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'. -Diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl- 4,4'-Diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis (3-amino-4-hydroxyphenyl) propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane Diamine, 2,2-bis (4-aminophenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 1,3-bis (3-aminophenoxy) benzene, 1,3- Bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, bis (4- (4-aminophenoxy) phenyl) sulfone, Examples thereof include bis (4- (3-aminophenoxy) phenyl) sulfone. Commercially available products may be used as the amine-based curing agent, for example, "KAYABOND C-200S", "KAYABOND C-100", "Kayahard A-A", "Kayahard AB", "Kayahard AB" manufactured by Nippon Kayaku Corporation. Examples include "Kayahard AS" and "Epicure W" manufactured by Mitsubishi Chemical Corporation.

Examples of the cyanate ester-based curing agent include bisphenol A dicyanate, polyphenol cyanate, oligo (3-methylene-1,5-phenylencyanate), 4,4'-methylenebis (2,6-dimethylphenylcyanate), and 4,4. '-Etilidene diphenyl disyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanate phenylmethane), bis (4-cyanate-3,5-dimethyl) Bifunctional cyanate resins such as phenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, and bis (4-cyanatephenyl) ether; Examples thereof include polyfunctional cyanate resins derived from phenol novolak, cresol novolak, and the like; prepolymers in which these cyanate resins are partially triazined. Specific examples of the cyanate ester-based curing agent include "PT30" and "PT60" manufactured by Lonza Japan Co., Ltd. (both are phenol novolac type polyfunctional cyanate ester resins); "ULL-950S" (polyfunctional cyanate ester resin); BA230 ”,“ BA230S75 ”(prepolymer in which part or all of bisphenol A dicyanate is triazined to form a trimer); and the like.

(B) The content of the curing agent is preferably 1% by mass or more, more preferably 5% by mass or more, when the non-volatile component in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the effect of the present invention. It is more preferably 10% by mass or more, preferably 25% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less.

When the number of epoxy groups of the component (A) is 1, the number of active groups of the (B) curing agent is preferably 0.1 or more, more preferably 0.3 or more, still more preferably 0.5 or more, and preferably 0.5 or more. It is 2 or less, more preferably 1.8 or less, still more preferably 1.5 or less. Here, the "number of epoxy groups of the component (A)" is a total value obtained by dividing the mass of the non-volatile component of the component (A) present in the resin composition by the epoxy equivalent. The "(B) number of active groups of the curing agent" is a total value obtained by dividing the mass of the non-volatile component of the (B) curing agent present in the resin composition by the active group equivalent. When the number of active groups of the (B) curing agent is in the above range when the number of epoxy groups of the component (A) is 1, the desired effect of the present invention can be remarkably obtained.

<(C) Inorganic filler>
The resin composition may contain (C) an inorganic filler as an arbitrary component and further as a component (C). An inorganic compound is used as the material of the inorganic filler. Examples of materials for inorganic fillers include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, Magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide , Barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, zirconium tungstate phosphate and the like. Of these, silica is particularly suitable. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica and the like. Further, as silica, spherical silica is preferable. The component (C) may be used alone or in combination of two or more.

Commercially available products of the component (C) include, for example, "UFP-30" manufactured by Denka; "SP60-05" and "SP507-05" manufactured by Nippon Steel & Sumikin Materials; "YC100C" manufactured by Admatex. "YA050C", "YA050C-MJE", "YA010C"; "Silfil NSS-3N", "Silfil NSS-4N", "Silfil NSS-5N" manufactured by Tokuyama Corporation; "SC2500SQ", "SO" manufactured by Admatex -C4 "," SO-C2 "," SO-C1 "; and the like.

The average particle size of the component (C) is preferably 0.01 μm or more, more preferably 0.05 μm or more, particularly preferably 0.1 μm or more, and preferably 0.1 μm or more, from the viewpoint of remarkably obtaining the desired effect of the present invention. It is 5 μm or less, more preferably 2 μm or less, still more preferably 1 μm or less.

The average particle size of the component (C) can be measured by a laser diffraction / scattering method based on the Mie scattering theory. Specifically, it can be measured by creating a particle size distribution of the inorganic filler on a volume basis by a laser diffraction / scattering type particle size distribution measuring device and using the median diameter as the average particle size. As the measurement sample, 100 mg of an inorganic filler and 10 g of methyl ethyl ketone can be weighed in a vial and dispersed by ultrasonic waves for 10 minutes. The measurement sample was measured using a laser diffraction type particle size distribution measuring device, the light source wavelengths used were blue and red, and the particle size distribution based on the volume of (C) the inorganic filler was measured by the flow cell method, and the obtained particles were obtained. The average particle size can be calculated as the median diameter from the diameter distribution. Examples of the laser diffraction type particle size distribution measuring device include "LA-960" manufactured by HORIBA, Ltd.

The specific surface area of the component (C) is preferably 1 m ² / g or more, more preferably 2 m ² / g or more, and particularly preferably 3 m ² / g or more, from the viewpoint of remarkably obtaining the desired effect of the present invention. The upper limit is not particularly limited, but is preferably 60 m ² / g or less, 50 m ² / g or less, or 40 m ² / g or less. The specific surface area is obtained by adsorbing nitrogen gas on the sample surface using a specific surface area measuring device (Macsorb HM-1210 manufactured by Mountech) according to the BET method and calculating the specific surface area using the BET multipoint method. ..

The component (C) is preferably treated with a surface treatment agent from the viewpoint of enhancing moisture resistance and dispersibility. Examples of the surface treatment agent include fluorine-containing silane coupling agents, aminosilane-based coupling agents, epoxysilane-based coupling agents, mercaptosilane-based coupling agents, silane-based coupling agents, alkoxysilanes, organosilazane compounds, and titanate-based agents. Coupling agents and the like can be mentioned. In addition, one type of surface treatment agent may be used alone, or two or more types may be used in any combination.

Commercially available surface treatment agents include, for example, "KBM-403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. and "KBM-503" (3-methacryloxypropyltri) manufactured by Shin-Etsu Chemical Co., Ltd. Methoxysilane), "KBM-803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBE-903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "3-aminopropyltriethoxysilane" manufactured by Shin-Etsu Chemical Co., Ltd. KBM-573 "(N-phenyl-3-aminopropyltrimethoxysilane)," SZ-31 "(hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd.," KBM-103 "(phenyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. ), "KBM-4803" (long-chain epoxy type silane coupling agent) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., etc. Will be.

The degree of surface treatment with the surface treatment agent is preferably within a predetermined range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 100 parts by mass of the inorganic filler is preferably surface-treated with 0.2 parts by mass to 5 parts by mass of a surface treatment agent, and is surface-treated with 0.2 parts by mass to 3 parts by mass. It is preferable that the surface is treated with 0.3 parts by mass to 2 parts by mass.

The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. Carbon content per unit surface area of the inorganic filler, from the viewpoint of improving dispersibility of the inorganic filler is preferably 0.02 mg / ^{m 2} or more, 0.1 mg / ^{m 2} or more preferably, 0.2 mg / ^{m 2} The above is more preferable. On the other hand, from the viewpoint of suppressing an increase in the melt viscosity of the resin varnish and the melt viscosity in the sheet form, 1 mg / m ² or less is preferable, 0.8 mg / m ² or less is more preferable, and 0.5 mg / m ² or less is further preferable. preferable.

The amount of carbon per unit surface area of the component (C) can be measured after the surface-treated inorganic filler is washed with a solvent (for example, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler surface-treated with the surface treatment agent, and ultrasonic cleaning is performed at 25 ° C. for 5 minutes. After removing the supernatant and drying the solid content, the amount of carbon per unit surface area of the inorganic filler can be measured using a carbon analyzer. As the carbon analyzer, "EMIA-320V" manufactured by HORIBA, Ltd. or the like can be used.

The content of the component (C) is preferably 20% by mass or more, more preferably 30% by mass or more, when the non-volatile component in the resin composition is 100% by mass from the viewpoint of lowering the coefficient of linear thermal expansion. It is more preferably 50% by mass or more, 70% by mass or more, preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less.

<(D) Curing accelerator>
The resin composition may contain (D) a curing accelerator as the component (D). Examples of the (D) curing accelerator include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, and metal-based curing accelerators. Among them, a phosphorus-based curing accelerator, an amine-based curing accelerator, an imidazole-based curing accelerator, and a metal-based curing accelerator are preferable, and an amine-based curing accelerator, an imidazole-based curing accelerator, and a metal-based curing accelerator are more preferable. (D) The curing accelerator may be used alone or in combination of two or more.

Examples of the phosphorus-based curing accelerator include triphenylphosphine, phosphonium borate compound, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, and (4-methylphenyl) triphenylphosphonium thiocyanate. , Tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate and the like, and triphenylphosphine and tetrabutylphosphonium decanoate are preferable.

Examples of the amine-based curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6, -tris (dimethylaminomethyl) phenol, and 1,8-diazabicyclo. Examples thereof include (5,4,0) -undecene, and 4-dimethylaminopyridine and 1,8-diazabicyclo (5,4,0) -undecene are preferable.

Examples of the imidazole-based curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, and the like. 2-Ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-Cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl- 2-Phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecyl Imidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4- Diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2- Phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazolin , 2-Imidazole compounds such as phenylimidazolin and adducts of imidazole compounds and epoxy resins are mentioned, with 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole being preferred.

As the imidazole-based curing accelerator, a commercially available product may be used, and examples thereof include "P200-H50" manufactured by Mitsubishi Chemical Corporation.

Examples of the guanidine-based curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1- (o-tolyl) guanidine, dimethylguanidine, diphenylguanidine, and trimethylguanidine. Tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo [4.4.0] deca-5-ene, 7-methyl-1,5,7-triazabicyclo [4.4.0] Deca-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylviguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1 Examples thereof include allylbiguanide, 1-phenylbiguanide, 1- (o-tolyl) biguanide, and dicyandiamide, 1,5,7-triazabicyclo [4.4.0] deca-5-ene is preferable.

Examples of the metal-based curing accelerator include organic metal complexes or organic metal salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organometallic complex include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. Examples thereof include an organic zinc complex such as iron (III) acetylacetonate, an organic nickel complex such as nickel (II) acetylacetonate, and an organic manganese complex such as manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, zinc stearate and the like.

The content of the component (D) is preferably 0.01% by mass or more, more preferably 0, when the non-volatile component in the resin composition is 100% by mass from the viewpoint of remarkably obtaining the desired effect of the present invention. It is 0.03% by mass or more, more preferably 0.05% by mass or more, preferably 0.3% by mass or less, more preferably 0.2% by mass or less, still more preferably 0.1% by mass or less.

<(E) Thermoplastic resin>
The resin composition may further contain (E) a thermoplastic resin as the component (E). Examples of the thermoplastic resin as the component (E) include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polycarbonate resin, and the like. Examples thereof include polyether ether ketone resin and polyester resin. Of these, the phenoxy resin is preferable from the viewpoint of remarkably obtaining the desired effect of the present invention. Further, (E) the thermoplastic resin may be used alone by one type, or may be used in combination of two or more types.

Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, novolak skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantan skeleton, and terpene. Examples thereof include phenoxy resins having one or more skeletons selected from the group consisting of skeletons and trimethylcyclohexane skeletons. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group.

Specific examples of the phenoxy resin include "1256" and "4250" manufactured by Mitsubishi Chemical Co., Ltd. (both are bisphenol A skeleton-containing phenoxy resins); "YX8100" manufactured by Mitsubishi Chemical Co., Ltd. (bisphenol S skeleton-containing phenoxy resin); "YX6954" (bisphenol acetophenone skeleton-containing phenoxy resin); "FX280" and "FX293" manufactured by Nittetsu Chemical &Materials; "YL7500BH30", "YX6954BH30", "YX7553", "YX7553BH30" manufactured by Mitsubishi Chemical Co., Ltd. , "YL7769BH30", "YL6794", "YL7213", "YL7290" and "YL7482"; and the like.

Examples of the polyvinyl acetal resin include polyvinyl formal resin and polyvinyl butyral resin, and polyvinyl butyral resin is preferable. Specific examples of the polyvinyl acetal resin include "Electrified Butyral 4000-2", "Electrified Butyral 5000-A", "Electrified Butyral 6000-C", and "Electrified Butyral 6000-EP" manufactured by Denki Kagaku Kogyo. Examples thereof include Eslek BH series, BX series (for example, BX-5Z), KS series (for example, KS-1), BL series, and BM series manufactured by the same company.

Specific examples of the polyimide resin include "Ricacoat SN20" and "Ricacoat PN20" manufactured by NEW JAPAN CHEMICAL CO., LTD. Specific examples of the polyimide resin include a linear polyimide obtained by reacting a bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (polyimide described in JP-A-2006-37083), and a polysiloxane skeleton. Examples thereof include modified polyimides such as contained polyimides (polyimides described in JP-A-2002-12667 and JP-A-2000-31386).

Specific examples of the polyamide-imide resin include "Vilomax HR11NN" and "Vilomax HR16NN" manufactured by Toyobo Co., Ltd. Specific examples of the polyamide-imide resin include modified polyamide-imides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamide-imide) manufactured by Hitachi Chemical Co., Ltd.

Specific examples of the polyether sulfone resin include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

Specific examples of the polysulfone resin include polysulfones "P1700" and "P3500" manufactured by Solvay Advanced Polymers.

(E) The weight average molecular weight (Mw) of the thermoplastic resin is preferably 8,000 or more, more preferably 10,000 or more, and particularly preferably 20,000 or more, from the viewpoint of remarkably obtaining the desired effect of the present invention. It is preferably 70,000 or less, more preferably 60,000 or less, and particularly preferably 50,000 or less.

The content of the (E) thermoplastic resin is preferably 0.1% by mass or more, more preferably 0.1% by mass, when the non-volatile component in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the desired effect of the present invention. Is 0.2% by mass or more, more preferably 0.3% by mass or more, preferably 5% by mass or less, more preferably 3% by mass or less, still more preferably 1% by mass or less.

<(F) Radical polymerizable resin>
The resin composition may contain (F) a radically polymerizable resin as the component (F). (F) By containing a radically polymerizable resin in the resin composition, it is possible to obtain a cured product having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient. Become.

（＊は結合手を表す。） As the component (F), a resin having a radically polymerizable unsaturated group can be used. The radically polymerizable group refers to a group having an ethylenic double bond that exhibits curability by irradiation with active energy rays such as ultraviolet rays or heat. Examples of such a group include a vinyl group, a vinylphenyl group, an acryloyl group, and a methacryloyl group, a maleimide group, a fumaloyl group, a maleoil group, and at least one selected from a vinylphenyl group, an acryloyl group, and a methacryloyl group. It is preferably a seed. Here, the acryloyl group and the methacryloyl group may be collectively referred to as "(meth) acryloyl group". The vinylphenyl group is a group having the following structure.

(* Indicates a bond.)

The component (F) contains two or more radically polymerizable unsaturated substances per molecule from the viewpoint of obtaining a cured product having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and coefficient of linear thermal expansion. It is preferable to have a radical.

The component (F) preferably has a cyclic structure from the viewpoint of obtaining a cured product having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient. As the cyclic structure, a divalent cyclic group is preferable. The divalent cyclic group may be either a cyclic group containing an alicyclic structure or a cyclic group containing an aromatic ring structure. Further, it may have a plurality of divalent cyclic groups.

The divalent cyclic group is preferably a 3-membered ring or more, more preferably a 4-membered ring or more, still more preferably a 5-membered ring or more, and preferably a 20-membered ring, from the viewpoint of remarkably obtaining the desired effect of the present invention. Hereinafter, it is more preferably 15-membered ring or less, still more preferably 10-membered ring or less. Further, the divalent cyclic group may have a monocyclic structure or a polycyclic structure.

The ring in the divalent cyclic group may be composed of a heteroatom other than a carbon atom to form a ring skeleton. Examples of the hetero atom include an oxygen atom, a sulfur atom, a nitrogen atom and the like, and an oxygen atom is preferable. The heteroatom may have one in the ring or two or more.

（２価の基（ｘｉｉ）、（ｘｉｉｉ）中、Ｒ^１、Ｒ^２、Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^１１、及びＲ^１２は、それぞれ独立にハロゲン原子、炭素原子数が６以下のアルキル基、又はフェニル基を表し、Ｒ^３、Ｒ^４、Ｒ^８、Ｒ^９、及びＲ^１０は、それぞれ独立に水素原子、ハロゲン原子、炭素原子数６以下のアルキル基、又はフェニル基を表す。） Specific examples of the divalent cyclic group include the following divalent groups (i) to (xiiii).

(In divalent group ^{(xii), (xiii),} R 1, R 2, R 5, R 6, R 7, R 11, and ^{R 12} are each independently a halogen atom, having 6 or less carbon atoms Represents an alkyl group or a phenyl group, and R ³ , R ⁴ , R ⁸ , R ⁹ , and R ¹⁰ independently represent a hydrogen atom, a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group, respectively. )

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group having 6 or less carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group and the like, and a methyl group is preferable. R ¹ , R ² , R ⁵ , R ⁶ , R ⁷ , R ¹¹ and R ¹² preferably represent a methyl group. R ³ , R ⁴ , R ⁸ , R ⁹ and R ¹⁰ are preferably hydrogen atoms or methyl groups.

（式（ａ）中、Ｒ^２１、Ｒ^２２、Ｒ^２５、Ｒ^２６、Ｒ^２７、Ｒ^３１、Ｒ^３２、Ｒ^３５及びＲ^３６は、それぞれ独立にハロゲン原子、炭素原子数が６以下のアルキル基、又はフェニル基を表し、Ｒ^２３、Ｒ^２４、Ｒ^２８、Ｒ^２９、Ｒ^３０、Ｒ^３３及びＲ^３４は、それぞれ独立に水素原子、ハロゲン原子、炭素原子数６以下のアルキル基、又はフェニル基を表す。ｎ及びｍは、０〜３００の整数を表す。但し、ｎ及びｍの一方は０である場合を除く。） Further, the divalent cyclic group may be a combination of a plurality of divalent cyclic groups. Specific examples of the combination of the divalent cyclic group include a divalent cyclic group represented by the following formula (a) (divalent group (a)).

In formula (a), R ²¹ , R ²² , R ²⁵ , R ²⁶ , R ²⁷ , R ³¹ , R ³² , R ³⁵ and R ³⁶ are independently halogen atoms and alkyl groups having 6 or less carbon atoms, respectively. , Or a phenyl group, and R ²³ , R ²⁴ , R ²⁸ , R ²⁹ , R ³⁰ , R ³³ and R ³⁴ independently represent a hydrogen atom, a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. N and m represent integers from 0 to 300, except when one of n and m is 0.)

R ²¹ , R ²² , R ³⁵ and R ³⁶ are the same ^{as R 1} in the divalent group (xii). R ²³ , R ²⁴ , R ³³ and R ³⁴ are the same ^{as R 3} in the divalent group (xii). R ²⁵ , R ²⁶ , R ²⁷ , R ³¹ , and R ³² are the same ^{as R 5} in the equation (xiii). R ²⁸ , R ²⁹ , and R ³⁰ are the same ^{as R 8} in the equation (xiii).

n and m represent integers from 0 to 300. However, this excludes the case where one of n and m is 0. As n and m, it is preferable to represent an integer of 1 to 100, more preferably an integer of 1 to 50, and even more preferably an integer of 1 to 10. n and m may be the same or different.

As the divalent cyclic group, a divalent group (x), a divalent group (xi) or a divalent group (a) is preferable, and a divalent group (x) or a divalent group (a) is preferable. Is more preferable.

The divalent cyclic group may have a substituent. Examples of such a substituent include a halogen atom, an alkyl group, an alkoxy group, an aryl group, an arylalkyl group, a silyl group, an acyl group, an acyloxy group, a carboxy group, a sulfo group, a cyano group, a nitro group and a hydroxy group. Examples thereof include a mercapto group and an oxo group, and an alkyl group is preferable.

The radically polymerizable unsaturated group may be directly bonded to a divalent cyclic group or may be bonded via a divalent linking group. Examples of the divalent linking group include an alkylene group, an alkaneylene group, an arylene group, a heteroarylene group, −C (= O) O−, −O−, −NHC (= O) −, and −NC (= O). N-, -NHC (= O) O-, -C (= O)-, -S-, -SO-, -NH- and the like can be mentioned, and a group in which a plurality of these are combined may be used. As the alkylene group, an alkylene group having 1 to 10 carbon atoms is preferable, an alkylene group having 1 to 6 carbon atoms is more preferable, an alkylene group having 1 to 5 carbon atoms, or an alkylene group having 1 to 4 carbon atoms. Is even more preferable. The alkylene group may be linear, branched or cyclic. Examples of such an alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a 1,1-dimethylethylene group and the like, and a methylene group, an ethylene group and 1,1 -Dimethylethylene groups are preferred. As the alkenylene group, an alkenylene group having 2 to 10 carbon atoms is preferable, an alkenylene group having 2 to 6 carbon atoms is more preferable, and an alkenylene group having 2 to 5 carbon atoms is further preferable. As the arylene group and the heteroarylene group, an arylene group or a heteroarylene group having 6 to 20 carbon atoms is preferable, and an arylene group or a heteroarylene group having 6 to 10 carbon atoms is more preferable. As the divalent linking group, an alkylene group is preferable, and a methylene group and a 1,1-dimethylethylene group are particularly preferable.

（式（１）中、Ｒ^５１及びＲ^５４はそれぞれ独立にラジカル重合性不飽和基を表し、Ｒ^５２及びＲ^５３はそれぞれ独立に２価の連結基を表す。環Ｂは、２価の環状基を表す。） The component (F) is preferably represented by the following formula (1).

In formula (1), R ⁵¹ and R ⁵⁴ each independently represent a radically polymerizable unsaturated group, and R ⁵² and R ⁵³ each independently represent a divalent linking group. Ring B is a divalent ring. Represents a radical.)

R ⁵¹ and R ⁵⁴ each independently represent a radically polymerizable unsaturated group, and a vinylphenyl group and a (meth) acryloyl group are preferable.

R ⁵² and R ⁵³ each independently represent a divalent linking group. The divalent linking group is the same as the above divalent linking group.

Ring B represents a divalent cyclic group. The ring B is the same as the above-mentioned divalent cyclic group.

Ring B may have a substituent. The substituent is the same as the substituent that the above divalent cyclic group may have.

（ｎ１は、式（ａ）中のｎと同じであり、ｍ１は、式（ａ）中のｍと同じである。） Hereinafter, specific examples of the component (F) will be shown, but the present invention is not limited thereto.

(N1 is the same as n in the formula (a), and m1 is the same as m in the formula (a).)

As the component (F), a commercially available product may be used, for example, "OPE-2St" manufactured by Mitsubishi Gas Chemical Company, "A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., and "DCP-A" manufactured by Kyoeisha Chemical Co., Ltd. "And so on. The component (B) may be used alone or in combination of two or more.

The number average molecular weight of the component (F) is preferably 3000 or less, more preferably 2500 or less, still more preferably 2000 or less and 1500 or less, from the viewpoint of remarkably obtaining the desired effect of the present invention. The lower limit is preferably 100 or more, more preferably 300 or more, still more preferably 500 or more, and 1000 or more. The number average molecular weight is a polystyrene-equivalent number average molecular weight measured using gel permeation chromatography (GPC).

The content of the component (F) is preferably 0.1% by mass or more, more preferably 0.3 when the non-volatile component in the resin composition is 100% by mass from the viewpoint of remarkably obtaining the effect of the present invention. By mass or more, more preferably 0.5% by mass or more. The upper limit is preferably 30% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less.

<(G) Polymerization Initiator>
The resin composition may contain (G) a polymerization initiator as the component (G). The component (G) usually has a function of promoting the cross-linking of radically polymerizable unsaturated groups in the component (F). The component (G) may be used alone or in combination of two or more.

Examples of the (G) polymerization initiator include t-butylcumyl peroxide, t-butylperoxyacetate, α, α'-di (t-butylperoxy) diisopropylbenzene, t-butylperoxylaurate, and t. -Butylperoxy-2-ethylhexanoate t-Butylperoxyneodecanoate, t-butylperoxybenzoate and other peroxides can be mentioned.

Examples of commercially available products of the (G) polymerization initiator include "Perbutyl C", "Perbutyl A", "Perbutyl P", "Perbutyl L", "Perbutyl O", "Perbutyl ND", and "Perbutyl ND" manufactured by NOF CORPORATION. Examples thereof include "Perbutyl Z", "Park Mill P", and "Park Mill D".

The content of the (G) polymerization initiator is preferably 0.01% by mass or more, more preferably, when the non-volatile component in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the desired effect of the present invention. Is 0.02% by mass or more, more preferably 0.03% by mass or more, preferably 0.3% by mass or less, more preferably 0.2% by mass or less, still more preferably 0.1% by mass or less. ..

<(H) Flame Retardant>
The resin composition may contain (H) a flame retardant as the component (H). Examples of the flame retardant (H) include a phosphazene compound, an organic phosphorus flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a silicone flame retardant, a metal hydroxide and the like, and a phosphazene compound is preferable. The flame retardant may be used alone or in combination of two or more.

The phosphazene compound is not particularly limited as long as it is a cyclic compound containing nitrogen and phosphorus as constituent elements, but the phosphazene compound is preferably a phosphazene compound having a phenolic hydroxyl group.

Specific examples of the phosphazene compound include, for example, "SPH-100", "SPS-100", "SPB-100" and "SPE-100" manufactured by Otsuka Chemical Co., Ltd., and "FP-100" manufactured by Fushimi Pharmaceutical Co., Ltd. Examples thereof include "FP-110", "FP-300", "FP-400" and the like, and "SPH-100" manufactured by Otsuka Chemical Co., Ltd. is preferable.

As the flame retardant other than the phosphazene compound, a commercially available product may be used, and examples thereof include "HCA-HQ" manufactured by Sanko Co., Ltd. and "PX-200" manufactured by Daihachi Chemical Industry Co., Ltd. As the flame retardant, one that is hard to hydrolyze is preferable, and for example, 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide and the like are preferable.

The content of the flame retardant (H) is preferably 0.1% by mass or more, more preferably 0.%, when the non-volatile component in the resin composition is 100% by mass from the viewpoint of remarkably obtaining the effect of the present invention. It is 2% by mass or more, more preferably 0.3% by mass or more. The upper limit is preferably 5% by mass or less, more preferably 3% by mass or less, and further preferably 1% by mass or less.

<(I) Other additives>
In addition to the above-mentioned components, the resin composition may further contain other additives as arbitrary components. Examples of such additives include resin additives such as thickeners, defoamers, leveling agents, and adhesion-imparting agents. These additives may be used alone or in combination of two or more. Each content can be appropriately set by those skilled in the art.

<Physical characteristics and uses of resin composition>
The cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes exhibits a characteristic of low dielectric constant. Therefore, the cured product provides an insulating layer having a low dielectric constant. The dielectric constant is preferably less than 3.0, more preferably 2.98 or less, and more preferably 2.95 or less. On the other hand, the lower limit of the dielectric constant is not particularly limited, but may be 0.0001 or more. The evaluation of the dielectric constant can be measured according to the method described in Examples described later.

A cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes usually exhibits a characteristic of having a low coefficient of linear thermal expansion (CTE). Therefore, the cured product provides an insulating layer having a low coefficient of linear thermal expansion. The coefficient of linear thermal expansion is preferably less than 30 ppm, more preferably 29 ppm or less, and more preferably 28 ppm or less. On the other hand, the lower limit of the coefficient of linear thermal expansion is not particularly limited, but may be 1 ppm or more. The evaluation of the linear thermal expansion coefficient can be measured according to the method described in Examples described later.

A cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes usually exhibits a characteristic that the glass transition temperature is high. Therefore, the cured product provides an insulating layer having a high glass transition temperature. The glass transition temperature is preferably 140 ° C. or higher, more preferably 150 ° C. or higher, still more preferably 160 ° C. or higher. On the other hand, the upper limit of the glass transition temperature is not particularly limited, but may be 300 ° C. or lower. The above-mentioned glass transition temperature can be measured according to the method described in Examples described later.

A cured product obtained by thermally curing a resin composition at 180 ° C. for 90 minutes usually exhibits a characteristic of excellent insulation reliability. Therefore, the cured product provides an insulating layer having excellent insulation reliability. Specifically, the initial resistance value of the insulating layer is measured at 7 points. Next, the resistance value after HAST after being left for 100 hours under the condition of 130 ° C. and 85% Rh is measured at 7 points. The case where the measured resistance value is greater than or equal to 10 ⁶ Omega and good initial and locations resistance are both good after HAST is preferably six or more, more preferably 7 positions. The above-mentioned evaluation of insulation reliability can be measured according to the method described in Examples described later.

The cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes exhibits the property of being excellent in mechanical strength. Therefore, the cured product provides an insulating layer having excellent mechanical strength. The mechanical strength can be evaluated by the elastic modulus and the elongation at break. The elastic modulus is preferably 20 GPa or less, more preferably 15 GPa or less, and further preferably 10 GPa or less. The lower limit of the elastic modulus is not particularly limited, but may be 0.1 GPa or more. The elongation at break is preferably 0.5% or more, more preferably 0.8% or more, still more preferably 1% or more. The upper limit is not particularly limited, but may be 10% or less. The above-mentioned measurement of mechanical strength can be performed according to the method described in Examples described later.

Even if the resin composition is thermally cured, bubbles are present in the cured product. Specifically, the resin composition is heat-cured at 180 ° C. for 90 minutes to obtain a cured product. When observing the cross section of the cured product, bubbles are present depending on the content of the bubbles. The specific experimental method can be measured according to the method described in Examples described later.

The resin composition of the present invention can provide an insulating layer having an excellent dielectric constant. In addition, the insulating layer is usually excellent in insulation reliability, mechanical strength, glass transition temperature (Tg), and coefficient of linear thermal expansion. Therefore, the resin composition of the present invention can be suitably used as a resin composition for insulating applications. Specifically, a resin composition for forming the insulating layer for forming the conductor layer (including the rewiring layer) formed on the insulating layer (resin for forming the insulating layer for forming the conductor layer). It can be suitably used as a composition).

Further, in the multilayer printed wiring board described later, a resin composition for forming an insulating layer of the multilayer printed wiring board (resin composition for forming an insulating layer of the multilayer printed wiring board) and an interlayer insulating layer of the printed wiring board are formed. (Resin composition for forming an interlayer insulating layer of a printed wiring board), and a resin composition for forming an insulating layer of a flexible substrate (resin composition for forming an insulating layer of a flexible substrate). be able to.

Further, for example, when the semiconductor chip package is manufactured through the following steps (1) to (6), the resin composition of the present invention is for a rewiring forming layer as an insulating layer for forming the rewiring layer. Can also be suitably used as a resin composition (resin composition for forming a rewiring forming layer) and a resin composition for encapsulating a semiconductor chip (resin composition for encapsulating a semiconductor chip). When the semiconductor chip package is manufactured, a rewiring layer may be further formed on the sealing layer.
(1) Step of laminating a temporary fixing film on a base material,
(2) A process of temporarily fixing a semiconductor chip on a temporary fixing film,
(3) Step of forming a sealing layer on a semiconductor chip,
(4) Step of peeling the base material and the temporary fixing film from the semiconductor chip,
(5) A step of forming a rewiring forming layer as an insulating layer on the surface from which the base material and the temporary fixing film of the semiconductor chip are peeled off, and (6) a rewiring layer as a conductor layer is formed on the rewiring forming layer. Forming process

[Manufacturing method of resin composition]
The method for producing the resin composition of the present invention can be produced, for example, by a method including the following step (a).
(A) A step of dispersing bubbles in a resin component having a viscosity at 25 ° C. of 300 mPa · s or more and 5000 mPa · s or less.

The resin component used in the step (a) represents a part or all of the components other than the (C) inorganic filler contained in the resin composition. As the resin component, (A) epoxy resin is preferable, and liquid epoxy resin is more preferable. The viscosity of the resin component at 23 ° C. is 300 mPa · s or more and 5000 mPa · s or less, and the preferable range of the viscosity is the same as the viscosity of the liquid epoxy resin. One type of resin component may be used alone, or two or more types may be used in combination. Further, the resin component may contain an organic solvent for adjusting the viscosity. The organic solvent is the same as the organic solvent used when preparing the resin varnish.

Further, from the viewpoint of effectively dispersing the bubbles in the resin component, the resin component preferably contains a surfactant.

Examples of the surfactant include cationic surfactants such as alkylamine salts, alkyltrimethylammonium salts and alkyldimethylbenzylammonium salts; fatty acid salts such as sodium oleate, alkylsulfate ester salts, alkylbenzenesulfonates and alkylsulfosuccinates. Anionic surfactants such as acid salts, naphthalene sulfonates, polyoxyethylene alkyl sulfates, alkane sulfonate sodium salts, alkyl diphenyl ether sulfonic acid sodium salts; polyoxyalkylene lauryl ethers, polyoxyethylene nonylphenyl ethers, polyoxyethylene Nonionic surfactants such as lauryl ether, polyoxyethylene styrylphenyl ether, polyoxyethylene octiphenyl ether, polyoxyethylene sorbitol tetraoleate, polyoxyethylene / polyoxypropylene copolymer, alkyl ether; fluorocarbon in the molecule Examples thereof include a fluorosurfactant having a chain. Of these, nonionic surfactants and fluorine-based surfactants are preferable from the viewpoint of remarkably obtaining the effects of the present invention.

As the surfactant, a commercially available product can be used. Examples of commercially available products include "Megafuck RS-72-K" manufactured by DIC, "LB-1520" manufactured by ADEKA, "T-81" manufactured by ADEKA, "NK-3" manufactured by ADEKA, and "NK-3" manufactured by ADEKA. "L-23", ADEKA "TR-701", ADEKA "PEG-1000", NOF "Nonion K-204", NOF "L-2", NOF "Nonion CP-08R", NOF's "Unistar E-275", NOF's "Monoguri D", NOF's "UNIOX HC-8" NOF's "UNIOX ST" -30E ”, NOF's“ Unigri GO-102R ”, NOF's“ Nymeen L-201 ”, NOF's“ Stahome F ”, NOF's“ Nymid MF-203 ” , "Unisafe A-LM" manufactured by NOF Corporation, "Marialim AKM1511-60" manufactured by NOF Corporation, and the like.

Regarding the content of the surfactant, from the viewpoint of allowing bubbles to stably exist in the resin composition, when the content of the resin component is 100% by mass, it is preferably 0.1% by mass or more, more preferably 0. .2% by mass or more, more preferably 0.3% by mass or more, preferably 5% by mass or less, more preferably 3% by mass or less, still more preferably 1% by mass or less.

As one embodiment of the step (a), the bubbles are directly dispersed in the liquid epoxy resin by using the bubbles of a bubble generator such as a microbubble generator in the liquid epoxy resin.

The frequency of the bubble generator is preferably 20 Hz or higher, more preferably 25 Hz or higher, still more preferably 30 Hz or higher, preferably 70 Hz or lower, and more preferably 70 Hz or lower, from the viewpoint of allowing bubbles to stably exist in the resin composition. It is 60 Hz or less, more preferably 50 Hz or less.

The bubble generation pressure of the bubble generator is 0.05 MPa or more, more preferably 0.1 MPa or more, still more preferably 0.2 MPa or more, and preferably 0.2 MPa or more, from the viewpoint of allowing the bubbles to stably exist in the resin composition. It is 0.5 MPa or less, more preferably 0.4 MPa or less, still more preferably 0.3 MPa or less.

The intake pressure of the bubble generator is preferably -0.5 MPa or more, more preferably -0.3 MPa or more, still more preferably -0.1 MPa or more, from the viewpoint of allowing bubbles to stably exist in the resin composition. It is preferably −0.001 MPa or less, more preferably −0.005 MPa or less, still more preferably −0.01 MPa or less.

The intake amount of the bubble generator is 1 mL / min or more, more preferably 5 mL / min or more, still more preferably 10 mL / min or more, preferably 40 mL, from the viewpoint of allowing bubbles to stably exist in the resin composition. It is less than / min, more preferably 30 mL / min or less, still more preferably 20 mL / min or less.

The operating time of the microbubble generator is preferably 3 minutes or more, more preferably 5 minutes or more, still more preferably 5 minutes or more per 5 kg of the resin component that disperses the bubbles, from the viewpoint of allowing the bubbles to stably exist in the resin composition. It is 10 minutes or more, preferably 120 minutes or less, more preferably 90 minutes or less, and further preferably 60 minutes or less.

The bubble ratio of the bubbles in the resin component is preferably 10% by volume or more, more preferably 30% by volume or more, still more preferably 50% by volume or more, and preferably 95% by volume from the viewpoint of remarkably obtaining the effect of the present invention. % Or less, more preferably 90% by volume or less, still more preferably 85% by volume or less. The bubble ratio is the content ratio of bubbles contained in the resin component in which the bubbles are dispersed (% by volume), and the resin component before the bubbles are dispersed in a container having a predetermined volume and the resin component after the bubbles are dispersed. It can be calculated by the following formula from the measured weight of each of the resin components of.
Bubble ratio (% by volume) = (1- (mass of resin component after dispersing bubbles / mass of resin component before dispersing bubbles)) × 100

The method for producing the resin composition may include (b) a step of mixing the resin component containing bubbles and the component to be contained in the resin composition other than the resin component, if necessary. Further, the method for producing the resin composition may include (c) a step of producing the resin composition by mixing and dispersing using a rotary mixer or the like. When preparing the resin composition or the resin varnish described later, the bubbles may associate with each other due to operations such as stirring, and the average particle size of the bubbles may increase. In particular, in the case of bubbles having a large average particle size, the bubbles tend to associate with each other by stirring or the like, and the average particle size tends to increase.

The bubbles contained in the resin composition obtained by the production method of the present invention are stably present for preferably 1 hour or longer, more preferably 2 hours or longer, still more preferably 3 hours or longer after the resin composition is manufactured. The upper limit is not particularly limited, but may be 30 days or less.

[Resin sheet]
The resin sheet of the present invention includes a support and a resin composition layer provided on the support and formed of the resin composition of the present invention.

The thickness of the resin composition layer is preferably 200 μm or less from the viewpoint of reducing the thickness of the printed wiring board and providing a cured product having excellent insulating properties even if the cured product of the resin composition is a thin film. It is preferably 180 μm or less, more preferably 150 μm or less. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be usually 5 μm or more.

Examples of the support include a film made of a plastic material, a metal foil, and a paper pattern, and a film made of a plastic material and a metal foil are preferable.

When a film made of a plastic material is used as a support, the plastic material may be, for example, polyethylene terephthalate (hereinafter abbreviated as "PET") or polyethylene naphthalate (hereinafter abbreviated as "PEN"). ) And other polyesters, polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylics such as polymethylmethacrylate (PMMA), cyclic polyolefins, triacetylcellulose (TAC), polyethersulfide (PES), polyethers. Examples thereof include ketones and polyimides. Of these, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is particularly preferable.

When a metal foil is used as the support, examples of the metal foil include copper foil, aluminum foil, and the like, and copper foil is preferable. As the copper foil, a foil made of a single metal of copper may be used, and a foil made of an alloy of copper and another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used. You may use it.

The support may be matted, corona-treated, or antistatic-treated on the surface to be joined to the resin composition layer.

Further, as the support, a support with a release layer having a release layer on the surface to be joined to the resin composition layer may be used. Examples of the release agent used for the release layer of the support with the release layer include one or more release agents selected from the group consisting of alkyd resin, polyolefin resin, urethane resin, and silicone resin. .. As the support with a release layer, a commercially available product may be used. For example, "SK-1" and "SK-1" manufactured by Lintec Corporation, which are PET films having a release layer containing an alkyd resin-based mold release agent as a main component. Examples include "AL-5", "AL-7", "Lumilar T60" manufactured by Toray Industries, "Purex" manufactured by Teijin Ltd., and "Unipee" manufactured by Unitika Ltd.

The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, and more preferably in the range of 10 μm to 60 μm. When a support with a release layer is used, the thickness of the entire support with a release layer is preferably in the above range.

In one embodiment, the resin sheet may further contain other layers, if necessary. Examples of such other layers include a protective film similar to the support provided on the surface of the resin composition layer that is not bonded to the support (that is, the surface opposite to the support). Be done. The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to suppress the adhesion and scratches of dust and the like on the surface of the resin composition layer.

For the resin sheet, for example, a resin varnish in which a resin composition is dissolved in an organic solvent is prepared, and this resin varnish is applied onto a support using a die coater or the like and further dried to form a resin composition layer. It can be manufactured by.

Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone (MEK) and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate; cellosolve and butyl carbitol and the like. Carbitols; aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone. The organic solvent may be used alone or in combination of two or more.

Drying may be carried out by a known method such as heating or blowing hot air. The drying conditions are not particularly limited, but the resin composition layer is dried so that the content of the organic solvent is 10% by mass or less, preferably 5% by mass or less. Although it depends on the boiling point of the organic solvent in the resin varnish, for example, when a resin varnish containing 30% by mass to 60% by mass of an organic solvent is used, the resin composition is obtained by drying at 50 ° C. to 150 ° C. for 3 to 10 minutes. A layer can be formed.

The resin sheet can be rolled up and stored. If the resin sheet has a protective film, it can be used by peeling off the protective film.

[Printed circuit board and its manufacturing method]
The printed wiring board of the present invention includes an insulating layer formed of a cured product of the resin composition of the present invention.

The printed wiring board can be manufactured, for example, by a method including the following steps (I) and (II).
(I) Step of forming a resin composition layer containing a resin composition on an inner layer substrate (II) A step of thermally curing the resin composition layer to form an insulating layer.

The resin composition layer in the step (I) may be formed by directly applying the resin composition onto the inner layer substrate, or may be formed by using the above-mentioned resin sheet, but may be formed by using the resin sheet. Is preferable. Therefore, a preferred embodiment of step (I) is a step of laminating a resin sheet on an inner layer substrate so that the resin composition layer of the resin sheet is bonded to the inner layer substrate.

The "inner layer substrate" used in the step (I) is a member that becomes a substrate of a printed wiring board, and is, for example, a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, and a thermosetting polyphenylene ether substrate. And so on. Further, the substrate may have a conductor layer on one side or both sides thereof, and the conductor layer may be patterned. An inner layer board in which a conductor layer (circuit) is formed on one side or both sides of the board may be referred to as an "inner layer circuit board". Further, an intermediate product in which an insulating layer and / or a conductor layer should be further formed when the printed wiring board is manufactured is also included in the "inner layer substrate" in the present invention. When the printed wiring board is a circuit board with built-in components, an inner layer board with built-in components can be used.

The inner layer substrate and the resin sheet can be laminated, for example, by heat-pressing the resin sheet to the inner layer substrate from the support side. Examples of the member for heat-pressing the resin sheet to the inner layer substrate (hereinafter, also referred to as “heat-bonding member”) include a heated metal plate (SUS end plate or the like) or a metal roll (SUS roll). It is preferable not to press the heat-bonded member directly onto the resin sheet, but to press it through an elastic material such as heat-resistant rubber so that the resin sheet sufficiently follows the surface irregularities of the inner layer substrate.

The inner layer substrate and the resin sheet may be laminated by a vacuum laminating method. In the vacuum laminating method, the heat crimping temperature is preferably in the range of 60 ° C. to 160 ° C., more preferably 80 ° C. to 140 ° C., and the heat crimping pressure is preferably 0.098 MPa to 1.77 MPa, more preferably 0. It is in the range of .29 MPa to 1.47 MPa, and the heat crimping time is preferably in the range of 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. Lamination is preferably carried out under reduced pressure conditions with a pressure of 26.7 hPa or less.

Lamination can be performed by a commercially available vacuum laminator. Examples of the commercially available vacuum laminator include a vacuum pressurizing laminator manufactured by Meiki Co., Ltd., a vacuum applicator manufactured by Nikko Materials, and a batch type vacuum pressurizing laminator.

After laminating, the laminated resin sheet may be smoothed by pressing under normal pressure (under atmospheric pressure), for example, from the support side. The press conditions for the smoothing treatment can be the same as the heat-bonding conditions for the above-mentioned lamination. The smoothing process can be performed by a commercially available laminator. The laminating and smoothing treatment may be continuously performed using the above-mentioned commercially available vacuum laminator.

The support may be removed between steps (I) and step (II) or after step (II).

In step (II), the resin composition layer is thermally cured to form an insulating layer. The thermosetting conditions of the resin composition layer are not particularly limited, and the conditions usually adopted when forming the insulating layer of the printed wiring board may be used.

For example, the thermosetting conditions of the resin composition layer differ depending on the type of the resin composition and the like, but the curing temperature is preferably 120 ° C. to 240 ° C., more preferably 150 ° C. to 220 ° C., still more preferably 170 ° C. to 210. ℃. The curing time can be preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, still more preferably 15 minutes to 100 minutes.

Before the resin composition layer is thermally cured, the resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermosetting the resin composition layer, the resin composition layer is heated at a temperature of 50 ° C. or higher and lower than 120 ° C. (preferably 60 ° C. or higher and 115 ° C. or lower, more preferably 70 ° C. or higher and 110 ° C. or lower). Preheating may be performed for 5 minutes or longer (preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes, still more preferably 15 minutes to 100 minutes).

Since the insulating layer is formed of the cured product of the resin composition of the present invention, the thickness of the insulating layer can be reduced. The thickness of the insulating layer is preferably 200 μm or less, more preferably 180 μm or less, still more preferably 150 μm or less, and 100 μm or less. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be usually 1 μm or more, 5 μm or more, or the like.

(II) After the step is completed, the support is peeled off in the step (III) from the viewpoint of obtaining an insulating layer having excellent dielectric constant, insulation reliability, mechanical strength, glass transition temperature (Tg), and linear thermal expansion coefficient. ..

In manufacturing the printed wiring board, (III) a step of drilling a hole in the insulating layer, (IV) a step of roughening the insulating layer, and (V) a step of forming a conductor layer may be further carried out. These steps (III) to (V) may be carried out according to various methods known to those skilled in the art used for manufacturing a printed wiring board. When the support is removed after the step (II), the support may be removed between the steps (II) and the step (III), between the steps (III) and the step (IV), or the step ( It may be carried out between IV) and step (V). Further, if necessary, the formation of the insulating layer and the conductor layer in steps (II) to (V) may be repeated to form a multilayer wiring board.

The step (III) is a step of drilling holes in the insulating layer, whereby holes such as via holes and through holes can be formed in the insulating layer. The step (III) may be carried out by using, for example, a drill, a laser, a plasma, or the like, depending on the composition of the resin composition used for forming the insulating layer. The dimensions and shape of the holes may be appropriately determined according to the design of the printed wiring board.

Step (IV) is a step of roughening the insulating layer. Usually, in this step (IV), smear removal is also performed. The procedure and conditions of the roughening treatment are not particularly limited, and known procedures and conditions usually used when forming the insulating layer of the printed wiring board can be adopted. For example, the insulating layer can be roughened by performing a swelling treatment with a swelling liquid, a roughening treatment with an oxidizing agent, and a neutralization treatment with a neutralizing liquid in this order. The swelling solution used for the roughening treatment is not particularly limited, and examples thereof include an alkaline solution and a surfactant solution, preferably an alkaline solution, and the alkaline solution is more preferably a sodium hydroxide solution or a potassium hydroxide solution. preferable. Examples of commercially available swelling liquids include "Swelling Dip Security SBU" and "Swelling Dip Security P" manufactured by Atotech Japan. Be done. The swelling treatment with the swelling liquid is not particularly limited, but can be performed, for example, by immersing the insulating layer in the swelling liquid at 30 ° C. to 90 ° C. for 1 minute to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling liquid at 40 ° C to 80 ° C for 5 to 15 minutes. The oxidizing agent used for the roughening treatment is not particularly limited, and examples thereof include an alkaline permanganate solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. The roughening treatment with an oxidizing agent such as an alkaline permanganate solution is preferably performed by immersing the insulating layer in an oxidizing agent solution heated to 60 ° C. to 100 ° C. for 10 to 30 minutes. The concentration of permanganate in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganate solutions such as "Concentrate Compact CP" and "Dozing Solution Security P" manufactured by Atotech Japan. The neutralizing solution used for the roughening treatment is preferably an acidic aqueous solution, and examples of commercially available products include "Reduction Solution Security Gant P" manufactured by Atotech Japan. The treatment with the neutralizing solution can be performed by immersing the treated surface that has been roughened with the oxidizing agent in the neutralizing solution at 30 ° C. to 80 ° C. for 1 minute to 30 minutes. From the viewpoint of workability and the like, a method of immersing the object roughened with an oxidizing agent in a neutralizing solution at 40 ° C to 70 ° C for 5 to 20 minutes is preferable.

In one embodiment, the arithmetic mean roughness (Ra) of the surface of the insulating layer after the roughening treatment is preferably 500 nm or less, more preferably 300 nm or less, still more preferably 200 nm or less. The lower limit is not particularly limited, but is preferably 30 nm or more, more preferably 40 nm or more, and further preferably 50 nm or more. The arithmetic mean roughness (Ra) of the insulating layer surface can be measured using a non-contact surface roughness meter.

The step (V) is a step of forming a conductor layer, and a conductor layer is formed on the insulating layer. The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer is one or more selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. Contains metal. The conductor layer may be a single metal layer or an alloy layer, and the alloy layer may be, for example, an alloy of two or more metals selected from the above group (for example, nickel-chromium alloy, copper, etc.). Examples include layers formed from nickel alloys and copper-titanium alloys). Among them, from the viewpoint of versatility, cost, ease of patterning, etc. for forming a conductor layer, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or a nickel-chromium alloy, copper, etc. A nickel alloy, a copper-titanium alloy alloy layer is preferable, a chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper single metal layer, or a nickel-chromium alloy alloy layer is more preferable, and a copper single metal layer is preferable. A metal layer is more preferred.

The conductor layer may have a single-layer structure, a single metal layer made of different types of metals or alloys, or a multi-layer structure in which two or more alloy layers are laminated. When the conductor layer has a multi-layer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc or titanium, or an alloy layer of nickel-chromium alloy.

The thickness of the conductor layer depends on the desired printed wiring board design, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

In one embodiment, the conductor layer may be formed by plating. For example, a conductor layer having a desired wiring pattern can be formed by plating the surface of an insulating layer by a conventionally known technique such as a semi-additive method or a full additive method, and the semi-additive can be manufactured from the viewpoint of ease of manufacture. It is preferably formed by the method. Hereinafter, an example of forming the conductor layer by the semi-additive method will be shown.

First, a plating seed layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern that exposes a part of the plating seed layer corresponding to a desired wiring pattern is formed on the formed plating seed layer. After forming a metal layer by electrolytic plating on the exposed plating seed layer, the mask pattern is removed. After that, the unnecessary plating seed layer can be removed by etching or the like to form a conductor layer having a desired wiring pattern.

Since the printed wiring board of the present invention contains an insulating layer formed by a cured product of the resin composition of the present invention, bubbles are contained in the insulating layer. The average particle size and the like of the bubbles in the insulating layer are the same as the average particle size and the like of the bubbles contained in the resin composition. Bubbles in the insulating layer can be confirmed, for example, by observing the cross section of the insulating layer.

[Semiconductor device]
The semiconductor device of the present invention includes the printed wiring board of the present invention. The semiconductor device of the present invention can be manufactured by using the printed wiring board of the present invention.

Examples of semiconductor devices include various semiconductor devices used in electric products (for example, computers, mobile phones, digital cameras, televisions, etc.) and vehicles (for example, motorcycles, automobiles, trains, ships, aircraft, etc.).

The semiconductor device of the present invention can be manufactured by mounting a component (semiconductor chip) on a conductive portion of a printed wiring board. The "conduction point" is a "place for transmitting an electric signal in the printed wiring board", and the place may be a surface or an embedded place. Further, the semiconductor chip is not particularly limited as long as it is an electric circuit element made of a semiconductor.

The mounting method of the semiconductor chip in manufacturing a semiconductor device is not particularly limited as long as the semiconductor chip functions effectively, but specifically, a wire bonding mounting method, a flip chip mounting method, and a bumpless build-up layer. Examples thereof include a mounting method using (BBUL), a mounting method using an anisotropic conductive film (ACF), a mounting method using a non-conductive film (NCF), and the like. Here, the "mounting method using the bumpless build-up layer (BBUL)" means "a mounting method in which the semiconductor chip is directly embedded in the recess of the printed wiring board and the semiconductor chip is connected to the wiring on the printed wiring board". Is.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. In the following description, "parts" and "%" mean "parts by mass" and "% by mass", respectively, unless otherwise specified. Unless otherwise specified, the test was carried out at room temperature and atmospheric pressure.

<Manufacturing Example 1: Production of Epoxy Resin 1 Containing Micro Bubbles>
A mixture of liquid bisphenol A type epoxy resin and liquid bisphenol F type epoxy resin (“ZX-1059” manufactured by Nittetsu Chemical & Materials Co., Ltd., epoxy equivalent about 165 g / eq., Viscosity at 25 ° C. 2200 mPa · s) is placed in a glass container. In addition, 5 kg was added, and a micro bubble generator (“MBelifeLab MBLL11-102V-S” manufactured by Kansai Autome Equipment Co., Ltd.) was connected to a glass container. After priming, the microbubble generator was operated for 30 minutes under the conditions of frequency 43 Hz, microbubble generation pressure 0.25 MPa, intake pressure −0.018 MPa, and intake amount 15 mL / min, and the microbubble-containing epoxy resin 1 Got

<Measurement of bubble rate of microbubbles>
A mixture of liquid bisphenol A type epoxy resin and liquid bisphenol F type epoxy resin (Nittetsu Chemical & Materials Co., Ltd.) and the mass (g) of 20 mL of the microbubble-containing epoxy resin 1 immediately after being obtained in a measuring cylinder. When 20 mL of "ZX-1059" manufactured by Epoxy Epoxy Equivalent (eq.) Was measured, the bubble ratio was calculated using the following formula from the mass (g) and found to be 45% by volume.
Bubble ratio (% by volume) = (1- (mass of microbubble-containing epoxy resin / mass of epoxy resin)) x 100

<Measurement of average particle size, standard deviation, and number of microbubbles>
Subsequently, a small amount of the microbubble-containing epoxy resin 1 immediately obtained was measured between glass plates provided with a gap of about 120 μm using a commercially available adhesive tape, and the observation range was arbitrary 1.2 mm × 1.6 mm. Microscopic observation was performed and the number of microbubbles was measured. Subsequently, the particle size of any 50 microbubbles within the observation range was measured, and the average particle size and standard deviation of the microbubbles were obtained from the obtained measured values. The average particle size was 36.5 μm and the standard deviation. Was 13.4 μm.

<Evaluation of stability of microbubbles>
Immediately after the obtained microbubble-containing epoxy resin 1, the microbubble-containing epoxy resin 1 was allowed to stand in a glass container. Regarding the microbubble-containing epoxy resin 1 immediately after being obtained and the microbubble-containing epoxy resin 1 left in a glass container for 3 hours and 24 hours, the above <measurement of average particle size, standard deviation, and number of microbubbles>. The average particle size and the number of microbubbles were measured by the same method as above. _{The number of microbubbles (N1 ini} ) and the average particle size (R1 _ini ) in the microbubble-containing epoxy resin 1 immediately after being obtained, the number of microbubbles (N1 _3h ) and the average particle size (R1 _3h ) after 3 hours. The number of microbubbles (N1 _24h ) and the average particle size (R1 _24h ) after 24 hours were compared and evaluated according to the following criteria.
⊚: 0.9 <(N1 _24h / N1 _ini ) and 0.9 <(R1 _24h / R1 _ini ) ≤ 1.1.
〇: Other than ◎, 0.9 <(N1 _3h / N1 _ini ) and 0.9 <(R1 _3h / R1 _ini ) ≤ 1.1.
Δ: Other than ⊚ and 〇, 0.3 <(N1 _3h / N1 _ini ) and 0.9 <(R1 _3h / R1 _ini ) ≤ 1.1.
×: Those that do not correspond to ◎, 〇, △

<Measurement of viscosity of liquid epoxy resin>
The viscosity of the liquid epoxy resin was measured at 25 ° C. with an E-type viscometer RE-80 (manufactured by Toki Sangyo Co., Ltd., rotor: 3 ° × R9.7). The rotation speed at the time of measurement was appropriately adjusted according to the viscosity of the liquid epoxy resin so as to be 10 to 90% of the measurable range at each rotation speed.

<Manufacturing Example 2: Production of Epoxy Resin 2 Containing Micro Bubbles>
In Production Example 1, 5 g of a fluorine-based surfactant (“Megafuck RS-72-K” manufactured by DIC Corporation) was additionally used. A microbubble-containing epoxy resin 2 was obtained in the same manner as in Production Example 1 except for the above items. When the microbubble content of the obtained microbubble-containing epoxy resin 2 was measured in the same manner as that of the microbubble-containing epoxy resin 1, it was 51% by volume, the average particle size of the microbubbles was 28.9 μm, and the standard deviation was 13.0 μm. rice field. Moreover, the stability of the microbubbles was evaluated in the same manner as in the microbubble-containing epoxy resin 1.

<Manufacturing Example 3: Production of Epoxy Resin 3 Containing Micro Bubbles>
In Production Example 1, 20 g of an ether-type nonionic surfactant (“LB-1520” manufactured by ADEKA, polyoxyalkylene lauryl ether) diluted with a 3-fold amount of methyl ethyl ketone in advance was additionally used. A microbubble-containing epoxy resin 3 was obtained in the same manner as in Production Example 1 except for the above items. When the microbubble content of the obtained microbubble-containing epoxy resin 3 was measured in the same manner as that of the microbubble-containing epoxy resin 1, it was 50% by volume, the average particle size of the microbubbles was 1.8 μm, and the standard deviation was 1.0 μm. rice field. Moreover, the stability of the microbubbles was evaluated in the same manner as in the microbubble-containing epoxy resin 1.

<Manufacturing Example 4: Production of Epoxy Resin 4 Containing Micro Bubbles>
In Production Example 1, a mixture of liquid bisphenol A type epoxy resin and liquid bisphenol F type epoxy resin (“ZX-1059” manufactured by Nittetsu Chemical & Materials Co., Ltd., epoxy equivalent of about 165 g / eq. ) 5 kg is changed to 5 kg of liquid 1,4-glycidylcyclohexane type epoxy resin (“ZX1658GS” manufactured by Nittetsu Chemical & Materials Co., Ltd., epoxy equivalent of about 135).
Change the frequency of the micro bubble generator from 43Hz to 60Hz,
The microbubble generation pressure of the microbubble generator was changed from 0.25 MPa to 0.20 MPa.
A microbubble-containing epoxy resin 4 was obtained in the same manner as in Production Example 1 except for the above items. When the microbubble content of the obtained microbubble-containing epoxy resin 4 was measured in the same manner as that of the microbubble-containing epoxy resin 1, it was 28% by volume, the average particle size of the microbubbles was 21.7 μm, and the standard deviation was 11.9 μm. rice field. Moreover, when the stability of the microbubbles was evaluated in the same manner as that of the microbubble-containing epoxy resin 1, the microbubbles disappeared after 1 hour.

<Manufacturing Example 5: Production of Epoxy Resin 5 Containing Micro Bubbles>
In Production Example 1, the intake pressure of the microbubble generator was changed from −0.018 MPa to −0.020 MPa, and the intake amount of the microbubble generator was changed from 15 mL / min to 25 mL / min.
A microbubble-containing epoxy resin 5 was obtained in the same manner as in Production Example 1 except for the above items. When the microbubble content of the obtained microbubble-containing epoxy resin 5 was measured in the same manner as that of the microbubble-containing epoxy resin 1, it was 58% by volume, the average particle size of the microbubbles was 55.1 μm, and the standard deviation was 22.2 μm. rice field. Moreover, the stability of the microbubbles was evaluated in the same manner as in the microbubble-containing epoxy resin 1.

<Example 1>
Biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. "NC-3000-L", epoxy equivalent about 269 g / eq.) 5 parts, Biphenyl AF type epoxy resin (Mitsubishi Chemical Co., Ltd. "YX7760", epoxy equivalent about 238 g / eq.). ) 5 parts, 3 parts of phosphazen resin (“SPS-100” manufactured by Otsuka Chemical Co., Ltd.), 10 parts of phenoxy resin (“YX7553BH30” manufactured by Mitsubishi Chemical Co., Ltd., 1: 1 solution of MEK and cyclohexanone with a solid content of 30% by mass) are MEK20. It was dissolved by heating in 37.8 parts of Solvent Nafsa with stirring. After cooling to room temperature, 86 parts of an active ester type curing agent (“EXB9416-70BK” manufactured by DIC, a methylisobutylketone solution having an active group equivalent of about 330 g / eq. And a non-volatile content of 70% by mass), a phenol-based curing agent ( 10 parts of "LA-3018-50P" manufactured by DIC, active group equivalent of about 151 g / eq., 2-methoxypropanol solution having a solid content of 50%, carbonidiimide-based curing agent ("V-03" manufactured by Nisshinbo Chemical Co., Ltd., active 10 parts of (meth) acrylate ("NK ester A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., molecular weight 326, (meth) acryloyl group equivalent 163 g / eq.) 5 parts, polymerization initiator (“Perbutyl C” manufactured by Nichiyu Co., Ltd.) 0.2 parts, curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution having a solid content of 5% by mass) 8 parts, aminosilane Spherical silica surface-treated with a system-based coupling agent (Shinetsu Chemical Industry Co., Ltd., "KBM-573") (average particle size 0.5 μm, specific surface area 5.9 m ² / g, Admatex Co., Ltd. “SO-C2” ) 400 parts were mixed, uniformly dispersed with a high-speed rotary mixer, filtered with a cartridge filter (“SHP100” manufactured by ROKICHNO), and defoamed under reduced pressure to obtain varnish intermediate 1. Then, 50 parts of the microbubble-containing epoxy resin 1 obtained in Production Example 1 was added to 600 parts of the varnish intermediate 1 and mixed with a planetary mixer to obtain a resin varnish 1. The content of the microbubbles in the resin varnish 1 was 10.5% by volume when the non-volatile component in the resin composition was 100% by volume. The average particle size of the bubbles in the resin varnish was 39.5 μm.

<Example 2>
In Example 1, 150 parts of the microbubble-containing epoxy resin was changed to 250 parts of the microbubble-containing epoxy resin. A resin varnish 2 was produced in the same manner as in Example 1 except for the above items. The content of the microbubbles in the resin varnish 2 was 13.0% by volume when the non-volatile component in the resin composition was 100% by volume. The average particle size of the bubbles in the resin varnish was 30.1 μm.

<Example 3>
In Example 1, spherical silica surface-treated with an aminosilane-based coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM-573”) (average particle size 0.5 μm, specific surface area 5.9 m ² / g, Admatex Co., Ltd.) The amount of "SO-C2") manufactured was changed from 400 copies to 380 copies.
An additional 20 parts of spherical silica ("UFP-30" manufactured by Denka Co., Ltd., average particle size 0.3 μm) surface-treated with an aminosilane-based coupling agent ("KBM-573" manufactured by Shin-Etsu Chemical Co., Ltd.) was used.
150 parts of the epoxy resin containing microbubbles was changed to 350 parts of the epoxy resin containing microbubbles.
Except for the above items, the resin varnish 3 was produced in the same manner as in Example 1. The content of the microbubbles in the resin varnish 3 was 12.3% by volume when the non-volatile component in the resin composition was 100% by volume. The average particle size of the bubbles in the resin varnish was 1.9 μm.

<Example 4>
In Example 1, 150 parts of the microbubble-containing epoxy resin was changed to 550 parts of the microbubble-containing epoxy resin. A resin varnish 4 was produced in the same manner as in Example 1 except for the above items. The content of the microbubbles in the resin varnish 4 was 5.2% by volume when the non-volatile component in the resin composition was 100% by volume. The average particle size of the bubbles in the resin varnish was 51.5 μm.

<Comparative Example 1>
In Example 1, 150 parts of the microbubble-containing epoxy resin was changed to 410 parts of the microbubble-containing epoxy resin.
40 parts of a mixture of liquid bisphenol A type epoxy resin and liquid bisphenol F type epoxy resin (“ZX-1059” manufactured by Nittetsu Chemical & Materials Co., Ltd., epoxy equivalent of about 165) was used.
A resin varnish 5 was produced in the same manner as in Example 1 except for the above items. The content of the microbubbles in the resin varnish 5 was 0% by volume when the non-volatile component in the resin composition was 100% by volume.

<Comparative Example 2>
30 parts of a mixture of liquid bisphenol A type epoxy resin and liquid bisphenol F type epoxy resin (Nittetsu Chemical & Materials Co., Ltd. "ZX-1059", epoxy equivalent about 165 g / eq.), Biphenyl type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.) "NC-3000-L", epoxy equivalent about 269 g / eq.) 25 parts, bisphenol AF type epoxy resin (Mitsubishi Chemical's "YX7760", epoxy equivalent about 238 g / eq.) 5 parts, phosphazen resin (Otsuka Chemical Co., Ltd.) 3 parts of "SPS-100" manufactured by Mitsubishi Chemical Co., Ltd., 10 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Co., Ltd., 1: 1 solution of MEK and cyclohexanone having a solid content of 30% by mass) are stirred in 20 parts of MEK and 40 parts of solvent naphtha. It was melted by heating. After cooling to room temperature, 86 parts of an active ester type curing agent (“EXB9416-70BK” manufactured by DIC, a methylisobutylketone solution having an active group equivalent of about 330 g / eq. And a non-volatile content of 70% by mass), a phenol-based curing agent ( 10 parts of "LA-3018-50P" manufactured by DIC, active group equivalent of about 151 g / eq., 2-methoxypropanol solution having a solid content of 50%, carbonidiimide-based curing agent ("V-03" manufactured by Nisshinbo Chemical Co., Ltd., active 10 parts of (meth) acrylate ("NK ester A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., molecular weight 326, (meth) acryloyl group equivalent 163 g / eq.) 5 parts, polymerization initiator (“Perbutyl C” manufactured by Nichiyu Co., Ltd.) 0.2 parts, curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution having a solid content of 5% by mass) 8 parts, aminosilane Spherical silica surface-treated with a system-based coupling agent (Shinetsu Chemical Industry Co., Ltd., "KBM-573") (average particle size 0.5 μm, specific surface area 5.9 m ² / g, Admatex Co., Ltd. “SO-C2” ) 300 parts, 100 parts of polytetrafluoroethylene (PTFE) particles (“Lubron L-2” manufactured by Daikin Industries, Ltd., average particle diameter 3 μm) are mixed and uniformly dispersed with a high-speed rotating mixer, and then a cartridge filter (ROKITECHNO) is used. The resin varnish 6 was obtained by filtering with “SHP100” manufactured by SHP100) and defoaming under reduced pressure. The content of the microbubbles in the resin varnish 6 was 0% by volume when the non-volatile component in the resin composition was 100% by volume.

<Comparative Example 3>
In Comparative Example 2, 100 parts of polytetrafluoroethylene (PTFE) particles (“Lubron L-2” manufactured by Daikin Industries, Ltd., average particle size 3 μm) were used as hollow glass particles (“Microbubbles iM30K” manufactured by 3M Japan Co., Ltd., average). Particle size 16 μm) 60 parts. A resin varnish 7 was produced in the same manner as in Comparative Example 2 except for the above items. The content of the microbubbles in the resin varnish 7 was 0% by volume when the non-volatile component in the resin composition was 100% by volume.

<Measurement of permittivity, coefficient of linear thermal expansion, glass transition temperature, and bubble content, and evaluation of process suitability>
(1) Preparation of hardened material for evaluation A glass cloth base material epoxy resin double-sided copper-clad laminate on the release agent-treated PET film (Lintec "501010", thickness 50 μm, 240 mm square) treated with a release agent. (Panasonic "R5715ES", thickness 0.7 mm, 255 mm square) was overlapped and the four sides were fixed with polyimide adhesive tape (width 10 mm) (hereinafter, may be referred to as "fixed PET film").

The resin varnishes 1 to 7 obtained in Examples and Comparative Examples were applied on the release-treated surface of the above-mentioned "fixed PET film" with a die coater so that the thickness of the resin composition layer after drying was 40 μm. , 80 ° C. to 120 ° C. (average 100 ° C.) for 6 minutes to obtain a resin sheet. The average particle size of the microbubbles in the obtained resin sheet was not significantly different from that of the microbubble-containing epoxy resins 1 to 5.

Then, the resin composition layer was heat-cured under the curing conditions of 90 minutes after being put into an oven at 180 ° C. After thermosetting, the polyimide adhesive tape is peeled off, the cured product is removed from the glass cloth base material epoxy resin double-sided copper-clad laminate, and the PET film (Lintec Corporation "501010") is also peeled off to obtain a sheet-shaped cured product. rice field. The obtained cured product is referred to as an "evaluation cured product".

(2) Measurement of permittivity The cured product for evaluation was cut into a length of 80 mm and a width of 2 mm and used as an evaluation sample. The relative permittivity of this evaluation sample was measured at a measurement frequency of 5.8 GHz and a measurement temperature of 23 ° C. by a cavity resonance perturbation method using an HP8362B device manufactured by Agilent Technologies. Measurements were made on the two test pieces, and the average value was calculated. The evaluation was based on the following criteria.
〇: Dielectric constant less than 3.0 ×: Dielectric constant 3.0 or more

(3) Measurement and evaluation of coefficient of linear thermal expansion and glass transition temperature The cured product for evaluation was cut into test pieces with a width of about 5 mm and a length of about 15 mm, and a thermomechanical analyzer ("Thermo Plus TMA8310" manufactured by Rigaku Co., Ltd.). Was used for thermomechanical analysis by the tensile weighting method. After the test piece was attached to the apparatus, measurements were made twice in succession under the measurement conditions of a load of 1 g and a heating rate of 5 ° C./min. In the second measurement, the glass transition temperature and the average coefficient of linear thermal expansion from 25 ° C to 150 ° C were calculated and evaluated based on the following criteria.
〇: Coefficient of linear thermal expansion is less than 30 ppm ×: Coefficient of linear thermal expansion is 30 ppm or more

(4) Evaluation of process suitability The cured product for evaluation was cross-sectionally observed at an observation magnification of 14,000 using a FIB-SEM composite device (“SMI3050SE” manufactured by SII Nanotechnology). From the obtained FIB-SEM images, the presence or absence of microbubbles was examined for Examples 1 to 4 and Comparative Example 1, and evaluated according to the following criteria. The measurement was performed on any 10 visual fields per one evaluation cured product.
〇: Microbubbles exist.
X: Microbubbles have disappeared.
Since Comparative Examples 2 and 3 did not contain microbubbles, it was not possible to evaluate the process suitability.

(5) Measurement of Bubble Content of Cured Product In the resin varnishes 1 to 5, resin varnishes similar to those of the resin varnishes 1 to 6 except that they did not contain microbubbles were produced. These resin varnishes are applied on the release-treated surface of the fixed PET film with a die coater so that the thickness of the resin composition layer after drying is 40 μm, and the temperature is 80 ° C to 120 ° C (average 100 ° C) 6 A resin sheet was obtained by drying for a minute.
Then, the resin composition layer was heat-cured under the curing conditions of 90 minutes after being put into an oven at 180 ° C. After thermosetting, the polyimide adhesive tape is peeled off, the cured product is removed from the glass cloth base material epoxy resin double-sided copper-clad laminate, and the PET film (Lintec Corporation "501010") is also peeled off to obtain a sheet-shaped cured product. rice field.
The specific gravity of the cured sheet-like product was measured using an analytical balance XP105 (using a specific gravity measuring kit) manufactured by METTLER TOLEDO. This is referred to as "ρref". Moreover, the specific gravity of the cured product for evaluation was measured in the same manner as the specific gravity of the cured product in the form of a sheet. This is referred to as "ρs". The bubble content (% by volume) was calculated from the following formula.
Bubble content (% by volume) of the cured product = (1- (ρs / ρref)) × 100
Since Comparative Examples 2 and 3 did not contain microbubbles, the bubble content of the cured product could not be measured.

<Evaluation of insulation reliability>
A resin composition layer was formed on a mold release surface of a polyethylene terephthalate film (“AL5” manufactured by Lintec Corporation, thickness 38 μm) with a mold release treatment using the resin varnishes 1 to 7 obtained in Examples and Comparative Examples as a support. A resin sheet with a support was prepared by uniformly applying the film so as to have a thickness of 40 μm and drying at 80 to 120 ° C. (average 100 ° C.) for 5 minutes. Next, the resin sheet with a support was laminated on a TAB tape having L / S = 20 μm / 20 μm using a batch type vacuum laminator (VP160 manufactured by Nichigo Morton). Then, the resin composition layer was cured by heating in a batch oven at 180 ° C. for 90 minutes to obtain an insulating layer. The resistance value of the insulating layer after curing was measured at 7 points, and then left in a HAST tester (manufactured by Kusumoto Kasei Co., Ltd., "ETAC PM422") at 130 ° C. and 85% Rh for 100 hours to set the resistance value to 7. Measured at a location. Insulation was the resistance value of more than 10 ⁶ Omega insulating good, less than 10 ⁶ Omega and insulating failure, insulation reliability was evaluated by the following criteria.
⊚: 7 samples with good insulation both in the initial stage and after HAST ○: 6 samples with good insulation both in the initial stage and after HAST.
Δ: Five samples with good insulation both at the initial stage and after HAST.
X: There are less than 5 samples with good insulation both in the initial stage and after HAST.

<Measurement of mechanical strength>
The cured product for evaluation was subjected to a tensile test using a Tensilon universal testing machine (“RTC-1250A” manufactured by Orientec Co., Ltd.) in accordance with Japanese Industrial Standards (JIS K7127), and the elastic modulus and break point elongation were measured.

Claims (17)

A resin composition containing bubbles. The resin composition according to claim 1, wherein the average particle size of the bubbles is 50 μm or less. The resin composition according to claim 1 or 2, wherein the bubbles are microbubbles. The resin composition according to any one of claims 1 to 3, which contains a liquid epoxy resin. The resin composition according to claim 4, wherein the content of the liquid epoxy resin is 1% by mass or more and 30% by mass or less when the non-volatile component in the resin composition is 100% by mass. The resin composition according to claim 4 or 5, wherein the liquid epoxy resin has a viscosity at 25 ° C. of 300 mPa · s or more and 5000 mPa · s or less. The resin composition according to any one of claims 1 to 6, which contains an inorganic filler. The resin composition according to claim 7, wherein the content of the inorganic filler is 20% by mass or more when the non-volatile component in the resin composition is 100% by mass. The resin composition according to any one of claims 1 to 8, which is used for forming an insulating layer. The resin composition according to any one of claims 1 to 9, which is used for forming an insulating layer for forming a conductor layer. A resin sheet comprising a support and a resin composition layer provided on the support and containing the resin composition according to any one of claims 1 to 10. A printed wiring board including an insulating layer formed of a cured product of the resin composition according to any one of claims 1 to 10. A semiconductor device comprising the printed wiring board according to claim 12. (A) A method for producing a resin composition, which comprises a step of dispersing bubbles in a resin component having a viscosity at 25 ° C. of 300 mPa · s or more and 5000 mPa · s or less. The method for producing a resin composition according to claim 14, wherein the resin component comprises a liquid epoxy resin. The method for producing a resin composition according to claim 14 or 15, wherein the bubble ratio of bubbles in the resin component is 30% by volume or more and 90% by volume or less. (I) A step of forming a resin composition layer containing the resin composition according to any one of claims 1 to 10 on an inner layer substrate, and (II) a process of thermally curing the resin composition layer to provide an insulating layer. A method of manufacturing a printed wiring board, including the process of forming.