JP7009838B2 - Resin composition - Google Patents

Description

The present invention relates to a resin composition. Further, the present invention relates to a resin sheet and a heat dissipation device using a resin composition.

In recent years, electronic devices have become smaller and more sophisticated, and the mounting density of semiconductor elements in printed wiring boards tends to increase. Along with the high functionality of the mounted semiconductor element, there is a demand for a technology for efficiently diffusing the heat generated by the semiconductor element.

For example, Patent Document 1 discloses that heat is diffused by using an insulating layer obtained by curing a high thermal conductive resin composition containing a resin and an inorganic filler having a specific average particle size for a printed wiring board. Has been done.

Japanese Unexamined Patent Publication No. 2013-189625

By the way, when a resin composition containing a heat conductive filler is cured to form an insulating layer, the thermal conductivity of the obtained insulating layer has a trade-off with the adhesion strength (peel strength) to a metal layer such as electrolytic copper foil. It is already known to be in a relationship. Specifically, by increasing the content of the thermally conductive filler in the resin composition, the thermal conductivity of the obtained insulating layer can be improved, but the adhesion strength of the obtained insulating layer to the metal layer is inferior. It ends up.

As a result of further studies, the present inventors may find that if the content of the thermally conductive filler is increased to such an extent that sufficient thermal conductivity is exhibited, the adhesion strength at a low temperature is inferior, especially when performing a thermal cycle test. all right.

The present invention is to provide a resin composition capable of obtaining an insulating layer having excellent thermal conductivity and adhesion strength to a metal layer at a low temperature; a resin sheet using the resin composition, and a heat dissipation device.

The present inventors have made a resin composition containing (A) an elastomer, (B-1) an epoxy resin liquid at 25 ° C., (C) a heat conductive filler, and (D) rubber particles, thereby providing thermal conductivity and heat conductivity. We have found that an insulating layer having excellent adhesion to a metal layer at a low temperature can be obtained, and have completed the present invention.

That is, the present invention includes the following contents.
[1] (A) Elastomer,
(B-1) Epoxy resin liquid at 25 ° C,
(C) thermally conductive filler, and (D) rubber particles,
A resin composition containing.
[2] The resin composition according to [1], wherein the cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes has an elongation of 4% or more.
[3] The resin composition according to [1] or [2], wherein the content of the component (C) is 80% by mass or more when the non-volatile component in the resin composition is 100% by mass.
[4] The resin composition according to any one of [1] to [3], wherein the component (C) is alumina.
[5] The resin composition according to any one of [1] to [4], wherein the component (C) is surface-treated with an aminosilane-based coupling agent.
[6] The thermal conductivity of the cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes is 1.5 W / m · K or more and 5.0 W / m · K or less, [1] to [5]. The resin composition according to any one of.
[7] The resin composition according to any one of [1] to [6], wherein the component (B-1) is a liquid at 25 ° C. and an epoxy equivalent is 250 g / eq or more.
[8] The resin composition according to any one of [1] to [7], further containing an epoxy resin other than the components (B-2) and (B-1).
[9] When the content of the component (B-1) is x and the total amount of all epoxy resins contained in the resin composition is y, x / y is 0.6 or more and 1 or less. [1] ] To [8].
[10] The component (A) is selected from a polybutadiene structure, a polysiloxane structure, a poly (meth) acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisobutylene structure, a polyisobutylene structure, and a polycarbonate structure in the molecule. The resin composition according to any one of [1] to [9], which is a resin having one or more kinds of structures.
[11] Described in any one of [1] to [10], wherein the component (A) is at least one selected from a resin having a glass transition temperature of 25 ° C. or lower and a resin liquid at 25 ° C. or lower. Resin composition.
[12] The resin composition according to any one of [1] to [11], wherein the component (A) has a functional group capable of reacting with the component (B-1).
[13] Of [1] to [12], the component (A) has one or more functional groups selected from a hydroxyl group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group and a urethane group. The resin composition according to any one.
[14] The resin composition according to any one of [1] to [13], wherein the component (A) has an imide structure.
[15] The resin composition according to any one of [1] to [14], wherein the component (A) has a phenolic hydroxyl group.
[16] The resin composition according to any one of [1] to [15], wherein the component (A) has a polybutadiene structure and a phenolic hydroxyl group.
[17] The resin composition according to any one of [1] to [16], which is used for adhering a heating element.
[18] 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 [17].
[19] The resin sheet according to [18], which is a resin sheet for adhering a heating element.
[20] A heat radiating device including an adhesive layer formed of a cured product of the resin composition according to any one of [1] to [17].

According to the present invention, a resin composition capable of obtaining an insulating layer having excellent thermal conductivity and adhesion strength to a metal layer at a low temperature; a resin sheet using the resin composition, and a heat dissipation device are provided. Can be done.

Hereinafter, the resin composition, the resin sheet, and the heat dissipation device of the present invention will be described in detail.

[Resin composition]
The resin composition of the present invention contains (A) an elastomer, (B-1) an epoxy resin liquid at 25 ° C., (C) a thermally conductive filler, and (D) rubber particles.

By using the components (A) to (D), it is possible to obtain an insulating layer having excellent thermal conductivity and adhesion strength to the metal layer at low temperature.

The resin composition further contains, if necessary, an epoxy resin other than the components (B-2) and (B-1), (E) a curing agent, (F) a curing accelerator, and (G) any additive. obtain. Hereinafter, each component contained in the resin composition will be described in detail.

In the present specification, the component (B-1) and the component (B-2) may be collectively referred to as "(B) epoxy resin".
Further, the “resin component” refers to a component of the non-volatile components constituting the resin composition, excluding the (C) thermally conductive filler described later. However, when an inorganic filler is included as an optional component, the "resin component" refers to a component of the non-volatile components constituting the resin composition, excluding (C) the heat conductive filler and the inorganic filler.

<(A) Elastomer>
The resin composition contains (A) an elastomer. In the present invention, the (A) elastomer means a flexible resin, which is an amorphous resin component that dissolves in an organic solvent, and a resin having rubber elasticity or a resin that exhibits rubber elasticity by polymerizing with other components is preferable. .. Examples of the rubber elasticity include a resin that conforms to the Japanese Industrial Standards (JIS K7161) and exhibits an elastic modulus of 1 GPa or less when a tensile test is performed at a temperature of 25 ° C. and a humidity of 40% RH. By using the component (A), it is possible to obtain an insulating layer having excellent adhesion strength to the metal layer at a low temperature. Further, the component (A) can usually reduce the elastic modulus of the insulating layer or increase the resistance to elongation.

In one embodiment, the component (A) is selected from a polybutadiene structure, a polysiloxane structure, a poly (meth) acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisobutylene structure, a polyisobutylene structure, and a polycarbonate structure in the molecule. It is preferable that the resin has one or more types of structures, and it is more preferable that the resin has one or more types of structures selected from a polybutadiene structure and a polycarbonate structure from the viewpoint of further enhancing flexibility.

Further, in another embodiment, the component (A) is preferably one or more selected from a resin having a glass transition temperature (Tg) of 25 ° C. or lower and a resin liquid at 25 ° C. or lower. The glass transition temperature of the resin having a glass transition temperature (Tg) of 25 ° C. or lower is preferably 20 ° C. or lower, more preferably 15 ° C. or lower. The lower limit of the glass transition temperature is not particularly limited, but may be usually −15 ° C. or higher. The resin that is liquid at 25 ° C. is preferably a resin that is liquid at 20 ° C. or lower, and more preferably a resin that is liquid at 15 ° C. or lower.

As a more preferable embodiment, the component (A) is one or more selected from resins having a glass transition temperature of 25 ° C. or lower and liquid at 25 ° C., and has a polybutadiene structure and a polysiloxane structure in the molecule. , A resin having one or more structures selected from a poly (meth) acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, and a polycarbonate structure is preferable.

The polybutadiene structure includes not only a structure formed by polymerizing butadiene but also a structure formed by hydrogenating the structure. Further, the butadiene structure may be partially hydrogenated or may be entirely hydrogenated. Further, the polybutadiene structure may be contained in the main chain or the side chain in the component (A).

Preferred examples of the polybutadiene resin are hydrided polybutadiene skeleton-containing resin, hydroxy group-containing polybutadiene resin, phenolic hydroxyl group-containing polybutadiene resin, carboxy group-containing polybutadiene resin, acid anhydride group-containing polybutadiene resin, epoxy group-containing polybutadiene resin, and isocyanate group. Examples thereof include a polybutadiene resin containing a urethane group and a polybutadiene resin containing a urethane group. Of these, a phenolic hydroxyl group-containing polybutadiene resin is more preferable. Here, the "hydrogenated polybutadiene skeleton-containing resin" refers to a resin in which at least a part of the polybutadiene skeleton is hydrogenated, and the polybutadiene skeleton does not necessarily have to be a completely hydrogenated resin. Examples of the hydrogenated polybutadiene skeleton-containing resin include a hydrogenated polybutadiene skeleton-containing epoxy resin. Examples of the phenolic hydroxyl group-containing polybutadiene resin include resins having a polybutadiene structure and having a phenolic hydroxyl group.

Specific examples of the polybutadiene resin, which is a resin having a polybutadiene structure in the molecule, include "Ricon 657" (polybutadiene containing an epoxy group), "Ricon 130MA8", "Ricon 130MA13", "Ricon 130MA20", and "Ricon 130MA20" manufactured by Clay Valley. "Ricon 131MA5", "Ricon 131MA10", "Ricon 131MA17", "Ricon 131MA20", "Ricon 184MA6" (polybutadiene containing acid anhydride group), "JP-100", "JP-200" (epoxy) manufactured by Nippon Soda Co., Ltd. Polybutadiene), "GQ-1000" (hydroxyl group, carboxyl group introduced polybutadiene), "G-1000", "G-2000", "G-3000" (both terminal hydroxyl group polybutadiene), "GI-1000", "GI" -2000 "," GI-3000 "(polybutadiene with hydroxylated hydroxyl groups at both ends)," PB3600 "," PB4700 "(polybutadiene skeleton epoxy compound)," Epofriend A1005 "," Epofriend A1010 "," Epo "Friend A1020" (epoxy compound of styrene, butadiene and styrene block copolymer), "FCA-061L" (hydrided polybutadiene skeleton epoxy compound), "R-45EPT" (polybutadiene skeleton epoxy compound), manufactured by Nagase ChemteX. And so on.

Further, as an example of a preferable polybutadiene resin, a linear polyimide using a hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride as raw materials (Japanese Patent Laid-Open No. 2006-37083, International Publication No. 2008/153208). ) Is also mentioned. The content of the polybutadiene structure of the polyimide resin is preferably 60% by mass to 95% by mass, more preferably 75% by mass to 85% by mass. For the details of the polyimide resin, the description of JP-A-2006-37083 and International Publication No. 2008/153208 can be referred to, and the contents thereof are incorporated in the present specification.

The polysiloxane structure is a structure containing a siloxane bond, and is contained in, for example, silicone rubber. The polysiloxane structure may be contained in the main chain or the side chain in the component (A).

Specific examples of the polysiloxane resin, which is a resin having a polysiloxane structure in the molecule, include "SMP-2006", "SMP-2003PGMEA", "SMP-5005PGMEA", amine group-terminated polysiloxane, manufactured by Shinetsu Silicone Co., Ltd. Examples thereof include linear polyimides made from basic acid anhydride (International Publication No. 2010/053185).

The poly (meth) acrylate structure is a structure formed by polymerizing acrylic acid or an acrylic acid ester, and also includes a structure formed by polymerizing methacrylic acid or a methacrylic acid ester. The (meth) acrylate structure may be contained in the main chain or the side chain in the component (A). Here, "(meth) acrylate" refers to methacrylate and acrylate.

Preferred examples of the poly (meth) acrylate resin, which is a resin having a poly (meth) acrylate structure in the molecule, include a hydroxy group-containing poly (meth) acrylate resin, a phenolic hydroxyl group-containing poly (meth) acrylate resin, and a carboxy group-containing resin. Poly (meth) acrylate resin, acid anhydride group-containing poly (meth) acrylate resin, epoxy group-containing poly (meth) acrylate resin, isocyanate group-containing poly (meth) acrylate resin, urethane group-containing poly (meth) acrylate resin, etc. Can be mentioned.

Specific examples of the poly (meth) acrylate resin include Teisan resin "SG-70L", "SG-708-6", "WS-023", "SG-700AS", and "SG-280TEA" manufactured by Nagase ChemteX Corporation. (Carboxy group-containing acrylic acid ester copolymer resin, acid value 5 to 34 mgKOH / g, weight average molecular weight 400,000 to 900,000, Tg-30 ° C to 5 ° C), "SG-80H", "SG-80H-" 3 ”,“ SG-P3 ”(epoxy group-containing acrylic acid ester copolymer resin, epoxy equivalent 4761 to 14285 g / eq, weight average molecular weight 350,000 to 850,000, Tg 11 ° C to 12 ° C),“ SG-600TEA ”, "SG-790" (hydroxy group-containing acrylic acid ester copolymer resin, hydroxyl value 20-40 mgKOH / g, weight average molecular weight 500,000-1.2 million, Tg-37 ° C--32 ° C), manufactured by Negami Kogyo Co., Ltd. "ME-2000", "W-116.3" (carboxy group-containing acrylic acid ester copolymer resin), "W-197C" (hydroxyl acid ester copolymer resin), "KG-25", " KG-3000 ”(epoxy group-containing acrylic acid ester copolymer resin) and the like can be mentioned.

The polyalkylene structure preferably has a predetermined number of carbon atoms. The specific number of carbon atoms of the polyalkylene structure is preferably 2 or more, more preferably 3 or more, particularly preferably 5 or more, preferably 15 or less, more preferably 10 or less, and particularly preferably 6 or less. Further, the polyalkylene structure may be contained in the main chain or the side chain in the component (A).

The polyalkylene oxy structure preferably has a predetermined number of carbon atoms. The specific number of carbon atoms of the polyalkylene oxy structure is preferably 2 or more, preferably 3 or more, more preferably 5 or more, preferably 15 or less, more preferably 10 or less, and particularly preferably 6 or less. The polyalkylene oxy structure may be contained in the main chain or the side chain in the component (A).

Specific examples of the polyalkylene resin, which is a resin having a polyalkylene structure in the molecule, and the polyalkyleneoxy resin, which is a resin having a polyalkylene oxy structure in the molecule, are "PTXG-1000" and "PTXG" manufactured by Asahi Kasei Fibers Corporation. -1800 "," YX-7180 "(resin containing an alkylene structure having an ether bond) manufactured by Mitsubishi Chemical Co., Ltd.," EXA-4850-150 "," EXA-4816 "," EXA-4822 "manufactured by DIC Corporation. , "EP-4000", "EP-4003", "EP-4010", "EP-4011" manufactured by ADEKA, "BEO-60E", "BPO-20E" manufactured by Shin Nihon Rika Co., Ltd., Mitsubishi Chemical Examples thereof include "YL7175" and "YL7410" manufactured by the same company.

The polyisoprene structure may be contained in the main chain or the side chain in the component (A). Specific examples of the polyisoprene resin, which is a resin having a polyisoprene structure in the molecule, include "KL-610" and "KL-613" manufactured by Kuraray.

The polyisobutylene structure may be contained in the main chain or the side chain in the component (A). Specific examples of the polyisobutylene resin, which is a resin having a polyisobutylene structure in the molecule, include "SIBSTAR-073T" (styrene-isobutylene-styrene triblock copolymer) and "SIBSTAR-042D" (styrene-styrene) manufactured by Kaneka. Isobutylene group block copolymer) and the like.

The polycarbonate structure may be contained in the main chain or the side chain in the component (A).

Preferred examples of the polycarbonate resin, which is a resin having a polycarbonate structure in the molecule, are a hydroxy group-containing polycarbonate resin, a phenolic hydroxyl group-containing polycarbonate resin, a carboxy group-containing polycarbonate resin, an acid anhydride group-containing polycarbonate resin, and an epoxy group-containing polycarbonate resin. , Polycarbonate resin containing isocyanate group, polycarbonate resin containing urethane group and the like.

Specific examples of the polycarbonate resin include "T6002" and "T6001" (polycarbonate diol) manufactured by Asahi Kasei Chemicals, and "C-1090", "C-2090" and "C-3090" (polycarbonate diol) manufactured by Kuraray. And so on.

Further, as an example of a preferable polycarbonate resin, a linear polyimide made from a hydroxyl group-terminated polycarbonate, a diisocyanate compound and a tetrabasic acid anhydride can be mentioned. The content of the polycarbonate structure of the polyimide resin is preferably 60% by mass to 95% by mass, more preferably 75% by mass to 85% by mass. The details of the polyimide resin can be referred to in International Publication No. 2016/129541, and the contents thereof are incorporated in the present specification.

The component (A) preferably has an imide structure. By having an imide structure, the heat resistance of the component (A) can be enhanced and the crack resistance can be effectively enhanced.

The component (A) may have any linear, branched, or cyclic structure, but is preferably linear from the viewpoint of exhibiting the desired effect of the present invention.

The component (A) preferably further has a functional group capable of reacting with the component (B), and particularly preferably has a functional group capable of reacting with the component (B-1). This functional group also includes reactive groups that appear upon heating. Since the component (A) has a functional group, the mechanical strength of the cured product of the resin composition can be improved.

Examples of the functional group include a carboxy group, a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, a urethane group and the like. Among them, from the viewpoint of remarkably obtaining the effect of the present invention, the functional group has one or more functional groups selected from a hydroxyl group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group and a urethane group. It is preferable, and a phenolic hydroxyl group is particularly preferable.

The component (A) may be used alone or in combination of two or more.

The component (A) preferably has a high molecular weight from the viewpoint of exhibiting excellent flexibility. The specific number average molecular weight Mn of the component (A) is preferably 4000 or more, more preferably 4500 or more, still more preferably 5000 or more, particularly preferably 5500 or more, preferably 100,000 or less, more preferably 95,000 or less. It is particularly preferably 90000 or less. When the number average molecular weight Mn of the component (A) is in the above range, the desired effect of the present invention can be remarkably obtained. (A) The number average molecular weight Mn of the component is a polystyrene-equivalent number average molecular weight measured by using GPC (gel permeation chromatography).

The specific weight average molecular weight of the component (A) is preferably 5500 to 100,000, more preferably 10,000 to 90,000, still more preferably 15,000 to 15,000, from the viewpoint of remarkably obtaining the desired effect of the present invention. It is 80,000. The weight average molecular weight of the component (A) is a polystyrene-equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

When the component (A) has a functional group, the functional group equivalent of the component (A) is preferably 100 or more, more preferably 200 or more, still more preferably 1000 or more, particularly preferably 2500 or more, and preferably 50,000 or less. , More preferably 30,000 or less, still more preferably 10,000 or less, and particularly preferably 5,000 or less. The functional group equivalent is the number of grams of the resin containing 1 gram equivalent of the functional group. For example, the epoxy group equivalent can be measured according to JIS K7236. Further, for example, the hydroxyl group equivalent can be calculated by dividing the molecular weight of KOH by the hydroxyl value measured according to JIS K1557-1.

The amount of the component (A) is preferably 10% by mass or more, more preferably 15% by mass or more, particularly preferably 20% by mass or more, and preferably 40% by mass or less, based on 100% by mass of the resin component. It is preferably 35% by mass or less, and particularly preferably 30% by mass or less. When the amount of the component (A) is in the above range, the desired effect of the present invention can be remarkably obtained.

<(B-1) Epoxy resin liquid at 25 ° C>
The resin composition contains (B-1) an epoxy resin that is liquid at 25 ° C. Since the component (B-1) is liquid at 25 ° C., it has excellent flexibility. Therefore, by incorporating the component (B-1) in the resin composition, it is possible to obtain an insulating layer that suppresses warpage and has excellent adhesion strength to the metal layer at low temperatures. Further, the component (B-1) can usually increase the resistance to elongation of the insulating layer.

The component (B-1) is usually liquid at 25 ° C., preferably liquid at 20 ° C. or lower, from the viewpoint of obtaining an insulating layer having suppressed warpage and excellent adhesion to the metal layer even at low temperatures. More preferably, it is liquid at 15 ° C. or lower.

The component (B-1) is not particularly limited as long as it is liquid at 25 ° C., for example, 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, alicyclic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin, glycidylamine type epoxy resin, epoxy resin having a butadiene structure, etc. Can be mentioned.

Specific examples of the component (B-1) include a highly repulsive elastic epoxy resin "YX7400" manufactured by Mitsubishi Chemical Corporation, an ultraflexible epoxy resin "YX7105", and "HP4032", "HP4032D", and "HP4032SS" manufactured by DIC. (Naphthalene type epoxy resin), "828US", "jER828EL", "825", "Epicoat 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), "630", "630LSD" (glycidylamine type epoxy resin), "ZX1059" manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd. (bisphenol A type epoxy resin and bisphenol F type epoxy resin) (Mixed product), "EX-721" (glycidyl ester type epoxy resin) manufactured by Nagase Chemtex, "Selokiside 2021P" (aliphatic epoxy resin having an ester skeleton) manufactured by Dycel, "PB-3600" (butadiene. Epoxy resin with structure), "ZX1658", "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin) manufactured by Nippon Steel & Sumitomo Metal Corporation, "630LSD" (glycidylamine type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd., etc. Can be mentioned. Among them, the high resilience epoxy resin "YX7400" and the ultraflexible epoxy resin "YX7105" manufactured by Mitsubishi Chemical Corporation are selected from the viewpoint of obtaining an insulating layer that suppresses warpage and has excellent adhesion to the metal layer even at low temperatures. preferable. These may be used individually by 1 type, or may be used in combination of 2 or more types.

The component (B-1) is liquid at 25 ° C. and has an epoxy equivalent of 250 g / eq or more from the viewpoint of obtaining an insulating layer having suppressed warpage and excellent adhesion to the metal layer even at a low temperature. preferable.

The epoxy equivalent of the component (B-1) is preferably 250 g / eq or more, more preferably 300 g / eq or more, still more preferably 350 g / eq or more or 400 g / eq or more. The lower limit is not particularly limited, but is preferably 1000 g / eq or less, more preferably 800 g / eq or less, and even more preferably 500 g / eq or less. Since the molecule of the component (B-1) having an epoxy equivalent within such a range is flexible, warpage is effectively suppressed, and an insulating layer having particularly excellent adhesion strength to a metal layer at a low temperature can be obtained.

The weight average molecular weight of the component (B-1) is preferably 100 to 5000, more preferably 250 to 3000, and further preferably 400 to 1500 from the viewpoint of remarkably obtaining the desired effect of the present invention. .. The weight average molecular weight of a resin such as an epoxy resin is a polystyrene-equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

The amount of the component (B-1) is preferably 1 mass with respect to 100% by mass of the non-volatile component in the resin composition from the viewpoint of obtaining an insulating layer in which warpage is suppressed and the adhesion strength to the metal layer at low temperature is excellent. % Or more, more preferably 2% by mass or more, particularly preferably 3% by mass or more, preferably 20% by mass or less, more preferably 15% by mass or less, and particularly preferably 10% by mass or less.

When the content of the component (B-1) is x and the total amount of all epoxy resins contained in the resin composition is y, x / y is preferably 0.6 or more, more preferably 0.65. Above, more preferably 0.7 or more. The upper limit is usually 1 or less. By setting the content of the component (B-1) within such a range with respect to all the epoxy resins, it becomes possible to obtain an insulating layer having particularly excellent adhesion strength to the metal layer at a low temperature. Here, the total epoxy resin means (B) epoxy resin, and means the total content of the component (B-1) and the component (B-2) described later. It is preferable that the above range is satisfied even when the component (B-1) is a liquid at 25 ° C. and has an epoxy equivalent of 250 g / eq or more.

<(C) Thermally conductive filler>
The resin composition contains (C) a thermally conductive filler. (C) By containing the heat conductive filler, an insulating layer having excellent thermal conductivity can be obtained. Here, the thermally conductive filler means an inorganic filler having a thermal conductivity of 20 W / m · K or more.

The material of the (C) thermally conductive filler is not particularly limited as long as the thermal conductivity is within the above range, and examples thereof include alumina, aluminum nitride, boron nitride, silicon carbide, and silicon nitride. Of these, alumina is particularly suitable. (C) The heat conductive filler may be used alone or in combination of two or more. Further, two or more kinds of the same materials may be used in combination.

(C) The average particle size of the thermally conductive filler is preferably 0.5 μm or more, more preferably 1.0 μm or more, and further, from the viewpoint of obtaining an insulating layer having excellent thermal conductivity and adhesion strength to the metal layer at low temperature. It is preferably 1.5 μm or more, preferably 10 μm or less, more preferably 7 μm or less, and further preferably 5 μm or less.

(C) The average particle size of particles such as a heat conductive filler 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 an inorganic filler on a volume basis using a laser diffraction / scattering type particle size distribution measuring device and using the median size as the average particle size. As the measurement sample, (C) a thermally conductive filler dispersed in water by ultrasonic waves can be preferably used. As the laser diffraction / scattering type particle size distribution measuring device, "LA-500" manufactured by HORIBA, Ltd., "SALD2200" manufactured by Shimadzu Corporation, or the like can be used. Specifically, the measurement can be performed according to the method described in Examples described later.

(C) The specific surface area of the heat conductive filler is preferably 0.1 m ² / g or more, more preferably 0., from the viewpoint of obtaining an insulating layer having excellent thermal conductivity and adhesion to the metal layer even at a low temperature. It is 5 m ² / g or more, more preferably 1 m ² / g or more, preferably 5 m ² / g or less, more preferably 4 m ² / g or less, still more preferably 3 m ² / g or less. (C) The specific surface area of the thermally conductive filler can be measured by the nitrogen BET method. Specifically, it can be measured using an automatic specific surface area measuring device. Examples of the automatic specific surface area measuring device include "Macsorb HM-1210" manufactured by Mountech. Specifically, the measurement can be performed according to the method described in Examples described later.

(C) The heat conductive filler may be surface-treated with a surface treatment agent from the viewpoint of enhancing moisture resistance and dispersibility. Examples of the surface treatment agent include aminosilane-based coupling agents, epoxysilane-based coupling agents, mercaptosilane-based coupling agents, silane-based coupling agents, alkoxysilane compounds, organosilazane compounds, titanate-based coupling agents, and the like. Above all, it is preferable that the surface is treated with an aminosilane-based coupling agent from the viewpoint of obtaining an insulating layer having excellent kneadability with an epoxy resin and excellent peel strength. The surface treatment agent may be used alone or in combination of two or more.

Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., and Shin-Etsu Chemical Co., Ltd. "KBE903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM5783" (N-) manufactured by Shin-Etsu Chemical Co., Ltd. (Phenyl-3-aminooctyltrimethoxysilane), "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM103" (phenyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM" manufactured by Shin-Etsu Chemical Co., Ltd. -4803 "(long-chain epoxy type silane coupling agent) and the like.

The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of (C) the heat conductive filler. The amount of carbon per unit surface area of the (C) thermally conductive filler is preferably 0.02 mg / m ^{2 or more, more preferably 0.05 mg / m 2 or} more from the viewpoint of improving the dispersibility of the (C) thermally conductive filler. It is preferable, and 0.1 mg / m ² or more 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 (C) thermally conductive filler can be measured after the surface-treated (C) thermally conductive 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 heat conductive filler (C) surface-treated with a surface treatment agent, and ultrasonically cleaned 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 (C) thermally conductive 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 (C) thermally conductive filler is preferably 100% by mass when the non-volatile component in the resin composition is 100% by mass from the viewpoint of obtaining an insulating layer having excellent thermal conductivity and adhesion strength to the metal layer at low temperature. It is 70% by mass or more, more preferably 75% by mass or more, and further preferably 80% by mass or more. The upper limit is preferably 95% by mass or less, more preferably 93% by mass or less, and further preferably 90% by mass or less.

<(D) Rubber particles>
The resin composition contains (D) rubber particles. (D) The rubber particles can be produced by increasing the molecular weight of the rubber component to a level at which it is not dissolved in the organic solvent and the resin component to form particles. Therefore, it does not dissolve in an organic solvent and is incompatible with other components such as an epoxy resin and a curing agent, so that it can exist in a dispersed state in a resin varnish and a resin composition. Normally, it functions as an organic filler having rubber elasticity. By including the rubber particles (D), the adhesion of the cured resin composition at low temperature can be improved. Further, by including the component (D) in the resin composition, the tackiness can be reduced and the handleability of the cured product of the resin composition can be improved. Further, the component (D) can usually lower the elastic modulus of the insulating layer or increase the resistance to elongation.

Examples of the rubber particles (D) include core-shell type rubber particles, cross-linked acrylonitrile-butadiene rubber particles, cross-linked styrene-butadiene rubber particles, acrylic rubber particles, and the like. Above all, core-shell type rubber particles are preferable from the viewpoint of remarkably obtaining the desired effect of the present invention.

The core-shell type rubber particles are rubber particles including a shell layer on the surface of the particles and a core layer inside the shell layer. For example, a core-shell type rubber particle including a shell layer formed of a polymer having a relatively high glass transition temperature and a core layer formed of a polymer having a relatively low glass transition temperature can be mentioned. Of these, core-shell type rubber particles in which the shell layer is formed of a glass-like polymer and the core layer is formed of a rubber-like polymer are preferable. The core-shell type rubber particles can suppress the aggregation of the rubber particles and enhance the dispersibility of the rubber particles in the components (A) and (B) and the resin components such as the curing agent described later by the shell layer. Moreover, the core layer can exhibit excellent rubber elasticity. The core-shell type rubber particles can be produced, for example, by seed-polymerizing one type or two or more types of monomers corresponding to each layer in a plurality of stages.

The core-shell type rubber particles may have a two-layer structure including only a shell layer and a core layer, but may further have a structure of three or more layers including an arbitrary layer. For example, the core-shell type rubber particles may contain an arbitrary layer between the shell layer and the core layer, or may contain an arbitrary layer inside the core layer. As a specific example, the core-shell type rubber particles include a shell layer formed of a glass-like polymer, a core layer formed of a rubber-like polymer, and an arbitrary core layer formed of a glass-like polymer inside the core layer. It may have a three-layer structure including the layer of.

In the core-shell type rubber particles, examples of the glassy polymer include acrylic polymers such as polymethylmethacrylate; styrene-based polymers such as polystyrene and styrene / divinylbenzene copolymers; Of these, acrylic polymers are preferable, and polymethylmethacrylate is particularly preferable. On the other hand, examples of the rubber-like polymer include acrylic rubber such as a homopolymer or copolymer of an acrylic monomer such as butyl acrylate; butadiene rubber such as polybutadiene; isoprene rubber; butyl rubber; and the like. Of these, acrylic rubber and butadiene rubber are preferable, and acrylic rubber is particularly preferable. Here, the term "acrylic monomer" includes acrylic acid esters, methacrylic acid esters, and combinations thereof.

Specific examples of core-shell type rubber particles include stafyroids "AC3832", "AC3816N", "IM401-7-17" manufactured by Aica Kogyo Co., Ltd .; "Metabren KW-4426" manufactured by Mitsubishi Chemical Corporation; Dow Chemical Japan. Examples include the pararoid "EXL-2655" manufactured by the company.

Specific examples of the crosslinked acrylonitrile butadiene rubber (NBR) particles include "XER-91" (average particle diameter 0.5 μm) manufactured by JSR Corporation.
Specific examples of the crosslinked styrene-butadiene rubber (SBR) particles include "XSK-500" (average particle diameter 0.5 μm) manufactured by JSR Corporation.
Specific examples of the acrylic rubber particles include Metabrene “W300A” (average particle diameter 0.1 μm) and “W450A” (average particle diameter 0.2 μm) manufactured by Mitsubishi Chemical Corporation.

(D) The rubber particles may be used alone or in combination of two or more.

(D) The rubber particles usually have an action of increasing the toughness of the cured product of the resin composition. Therefore, the insulating layer formed of the cured product of the resin composition containing (D) rubber particles is excellent in mechanical strength. Further, the rubber particles (D) usually have a stress relaxation effect. Therefore, in the insulating layer formed of the cured product of the resin composition containing (D) rubber particles, the internal stress generated at the time of formation is relaxed by (D) rubber particles. Therefore, since the residual stress of the insulating layer can be reduced, the mechanical strength of the insulating layer can also be increased. Therefore, peeling (delamination) of the insulating layer can be suppressed even at a low temperature.

The average particle size of the rubber particles (D) is preferably 0.005 μm or more, more preferably 0.2 μm or more, preferably 1 μm or less, and more preferably 0.6 μm or less. (D) The average particle size of the rubber particles can be measured by using a dynamic light scattering method. Specifically, the rubber particles are uniformly dispersed in an appropriate organic solvent by a method such as ultrasonic waves, and the particle size distribution of the rubber particles is distributed using a concentrated particle size analyzer (“FPAR-1000” manufactured by Otsuka Electronics Co., Ltd.). Can be prepared on the basis of mass, and its median diameter can be measured as the average particle diameter.

The content of the rubber particles (D) is usually 0.3 with respect to 100% by mass of the non-volatile component in the resin composition from the viewpoint of improving the adhesion and tackiness of the cured product of the resin composition at low temperature. It is mass% or more, preferably 0.5% by mass or more, particularly preferably 1% by mass or more, usually 6% by mass or less, preferably 5% by mass or less, and particularly preferably 4% by mass or less.

<Epoxy resin other than (B-2) and (B-1) components>
The resin composition may contain an epoxy resin other than the components (B-2) and (B-1). The component (B-2) is usually preferably a solid epoxy resin (sometimes referred to as “solid epoxy resin”) at a temperature of 20 ° C.

The component (B-2) preferably contains an epoxy resin having two or more epoxy groups in one molecule. 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 50 with respect to 100% by mass of the non-volatile component of the component (B-2). It is by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in one molecule is preferable. Examples of the solid epoxy resin include bixilenol type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, aliphatic epoxy resin, and trisphenol type epoxy resin. , Naftor type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, anthracene type epoxy resin, bisphenol A type epoxy resin, bisphenol AF type epoxy resin and the like. Examples of the aliphatic epoxy resin include a dicyclopentadiene type epoxy resin.

As the component (B-2), an aliphatic epoxy resin is preferable from the viewpoint of obtaining the desired effect of the present invention. Above all, from the viewpoint of remarkably obtaining the desired effect of the present invention, the component (B-2) is preferably a dicyclopentadiene type epoxy resin.

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" (dicyclopentadiene type epoxy resin); "HP-7200HH", "HP-7200H", "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" manufactured by DIC Naphthylene 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 aralkyl type epoxy resin); "ESN475V" (naphthol type epoxy resin) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .; "ESN485" (naphthol) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. 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); "PG-100" and "CG-500" (bisphenol AF type epoxy resin) manufactured by Osaka Gas Chemical Co., Ltd .; "YL7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd. "YL7800" manufactured by Mitsubishi Chemical Co., Ltd. (fluorene type epoxy resin); "jER1010" manufactured by Mitsubishi Chemical Co., Ltd. (solid bisphenol A type epoxy resin); "jER1031S" manufactured by Mitsubishi Chemical Co., Ltd. (tetraphenylethane type epoxy resin) ; Can be mentioned. These may be used individually by 1 type, or may be used in combination of 2 or more types.

The epoxy equivalent of the component (B-2) is preferably 50 to 5000, more preferably 50 to 3000, still more preferably 80 to 2000, and particularly preferably 110 to 1000. (A) When the epoxy equivalent of the epoxy resin is within the above range, the crosslink density of the cured product of the resin composition becomes sufficient, and an insulating layer having a small surface roughness can be obtained. The epoxy equivalent is the mass of the resin containing 1 equivalent of the epoxy group, and can be measured according to JIS K7236.

The weight average molecular weight of the component (B-2) is preferably 100 to 5000, more preferably 250 to 3000, and further preferably 400 to 1500 from the viewpoint of remarkably obtaining the desired effect of the present invention. .. The weight average molecular weight of a resin such as an epoxy resin is a polystyrene-equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

When the resin composition contains the component (B-2), the amount of the component (B-2) is 100 mass by mass of the non-volatile component in the resin composition from the viewpoint of obtaining an insulating layer exhibiting good mechanical strength and insulation reliability. % By mass, preferably 0.3% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1.0% by mass or more, preferably 5% by mass or less, and more preferably 4% by mass or less. Particularly preferably, it is 3% by mass or less.

<(E) Curing agent>
The resin composition may contain (E) a curing agent. The curing agent is not particularly limited as long as it has a function of curing the resin such as the component (B), and for example, a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent, a benzoxazine-based curing agent, and a cyanate ester. Examples thereof include a system curing agent and a carbodiimide system curing agent. The curing agent may be used alone or in combination of two or more. The component (E) is preferably one or more selected from a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent, and a cyanate ester-based curing agent, and is preferably a phenol-based curing agent and an active ester-based curing agent. It is preferably one or more selected from the agents, and more preferably contains a naphthol-based curing agent.

As the phenol-based curing agent and the naphthol-based curing agent, a phenol-based curing agent having a novolak structure or a naphthol-based curing agent having a novolak structure is preferable from the viewpoint of heat resistance and water resistance. Further, from the viewpoint of adhesion to the wiring layer, a nitrogen-containing phenol-based curing agent is preferable, and a triazine skeleton-containing phenol-based curing agent is more preferable. Of these, a triazine skeleton-containing phenol novolac curing agent is preferable from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion to the wiring layer.

Specific examples of the phenol-based curing agent and the naphthol-based curing agent include "MEH-7700", "MEH-7810", "MEH-7851" manufactured by Meiwa Kasei Co., Ltd., and "NHN" and "CBN" manufactured by Nippon Kayaku Co., Ltd. , "GPH", "SN170", "SN180", "SN190", "SN475", "SN485", "SN495V", "SN375", "SN395" manufactured by Nippon Steel & Sumitomo Metal Corporation, "TD-" manufactured by DIC Corporation. 2090, "LA-7052", "LA-7054", "LA-1356", "LA-3018-50P", "EXB-9500", "HPC-9500", "KA-1160", "KA-" "1163", "KA-1165", "GDP-6115L" manufactured by Gunei Chemical Co., Ltd., "GDP-6115H" and the like can be mentioned.

The active ester-based curing agent is not particularly limited, but generally contains an ester group having high reaction activity such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds in one molecule. A compound having two or more esters is preferably used. 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.

Specifically, 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 an active ester compound containing a benzoylated product of phenol novolac are preferable. 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 the active ester-based curing agent include "EXB9451", "EXB9460", "EXB9460S", "HPC-8000-65T", and "HPC-8000H-" as active ester compounds containing a dicyclopentadiene type diphenol structure. "65TM", "EXB-8000L-65TM" (manufactured by DIC), "EXB9416-70BK" (manufactured by DIC) as an active ester compound containing a naphthalene structure, and "DC808" (manufactured by DIC) as an active ester compound containing an acetylated product of phenol novolac. Mitsubishi Chemical Co., Ltd.), "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.) as an active ester compound containing a benzoylated product of phenol novolac, "DC808" (manufactured by Mitsubishi Chemical Co., Ltd.) as an active ester-based curing agent which is an acetylated product of phenol novolac. Examples of the active ester-based curing agent which is a benzoylated product of phenol novolac include "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.), "YLH1030" (manufactured by Mitsubishi Chemical Co., Ltd.), "YLH1048" (manufactured by Mitsubishi Chemical Co., Ltd.) and the like.

Specific examples of the benzoxazine-based curing agent include "HFB2006M" manufactured by Showa High Polymer Co., Ltd., "Pd" and "FA" manufactured by Shikoku Chemicals 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. '-Etilidendiphenyl disyanate, hexafluorobisphenol A disyanate, 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, phenol. Examples thereof include polyfunctional cyanate resins derived from novolak and cresol novolak, and prepolymers in which these cyanate resins are partially triazined. Specific examples of the cyanate ester-based curing agent include "PT30" and "PT60" (both are phenol novolac type polyfunctional cyanate ester resins), "BA230", and "BA230S75" (part of bisphenol A dicyanate) manufactured by Lonza Japan. Alternatively, a prepolymer in which the whole is triazined to become a trimer) and the like can be mentioned.

Specific examples of the carbodiimide-based curing agent include "V-03" and "V-07" manufactured by Nisshinbo Chemical Co., Ltd.

When the resin composition contains the component (E), the content of the curing agent in the resin composition is not particularly limited, but when the non-volatile component in the resin composition is 100% by mass, it is preferably 5% by mass or less. , More preferably 3% by mass or less, still more preferably 2% by mass or less. The lower limit is not particularly limited, but is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more.

<(F) Curing accelerator>
The resin composition of the present invention may contain (F) a curing accelerator. Examples of the curing accelerator include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, metal-based curing accelerators, and the like, and phosphorus-based curing accelerators and amine-based curing agents. Curing accelerators, imidazole-based curing accelerators, and metal-based curing accelerators are preferable, and amine-based curing accelerators, imidazole-based curing accelerators, and metal-based curing accelerators are more preferable. 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-methylimidazoline Examples thereof include imidazole compounds such as 2-phenylimidazolin and adducts of the imidazole compound and an epoxy resin, and 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole are preferable.

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 -Allylbiguanide, 1-phenylbiguanide, 1- (o-tolyl) biguanide and the like can be mentioned, with dicyandiamide and 1,5,7-triazabicyclo [4.4.0] deca-5-ene being preferred.

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.

When the resin composition contains the component (F), the content of the curing accelerator in the resin composition is not particularly limited, but when the non-volatile component in the resin composition is 100% by mass, it is preferably 0.01. By mass or more, more preferably 0.03% by mass or more, particularly preferably 0.05% by mass or more, preferably 3% by mass or less, more preferably 1.5% by mass or less, and particularly preferably 1% by mass or less. Is.

<(G) Arbitrary additive>
The resin composition may further contain other additives, if necessary, and such other additives include, for example, an inorganic filler (excluding those corresponding to the component (C)) and heat. Organometallic compounds such as plastic resins, organic copper compounds, organic zinc compounds and organic cobalt compounds, and resin additives such as binders, thickeners, defoaming agents, leveling agents, adhesion-imparting agents, and colorants. Can be mentioned.

The inorganic filler is an inorganic filler having a thermal conductivity of less than 20 W / m · K. Materials for the inorganic filler include, for example, silica, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, hydroxylated. Magnesium, calcium carbonate, magnesium carbonate, magnesium oxide, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconate titanate, barium titanate, lead zirconate titanate Examples thereof include barium acid, barium zirconate, calcium zirconate, zirconate titer, zirconate titanate and the like.

The average particle size of the inorganic filler is preferably 0.01 μm or more, more preferably 0.05 μm or more, still more preferably 0.1 μm or more, and preferably 5 μm or less, more preferably 2.5 μm or less, further. It is preferably 2.2 μm or less, and particularly preferably 2 μm or less.

As the inorganic filler, a commercially available product may be used, for example, "YC100C", "YA050C", "YA050C-MJE", "YA010C" manufactured by Admatex Co., Ltd .; "UFP-30" manufactured by Denki Kagaku Kogyo Co., Ltd.; "Silfil NSS-3N", "Silfil NSS-4N", "Silfil NSS-5N"; Admatex "SC2500SQ", "SO-C6", "SO-C4", "SO-C2", "Silfil NSS-3N" SO-C1 ”; and the like.

Examples of the thermoplastic resin include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polyetheretherketone resin, and the like. Examples include polyester resin.

Commercially available products may be used as the thermoplastic resin, for example, "YX7553BH30" and "YX7891BH30" manufactured by Mitsubishi Chemical Corporation, KS series manufactured by Sekisui Chemical Co., Ltd., and "Ricacoat SN20" manufactured by Shin Nihon Rika Co., Ltd. Examples include "Ricacoat PN20" and "OPE-2St 1200" manufactured by Mitsubishi Gas Chemical Company.

<Physical characteristics of resin composition>
The cured product obtained by thermally curing the resin composition of the present invention at 180 ° C. for 90 minutes usually exhibits a characteristic of being excellent in adhesion strength (peel strength) with a metal layer. The peel strength is preferably 0.4 kgf / cm or more, more preferably 0.45 kgf / cm or more, and further preferably 0.5 kgf / cm or more. On the other hand, the upper limit of the peel strength is not particularly limited, but may be 2.0 kgf / cm or less, 1.5 kgf / cm or less, or the like. The evaluation of peel strength can be measured according to the method described in Examples described later.
The metal layer is preferably a metal layer containing copper, and more preferably an electrolytic copper foil.

A cured product obtained by thermally curing the resin composition of the present invention at 180 ° C. for 90 minutes usually exhibits a characteristic of excellent thermal conductivity. The thermal conductivity is preferably 1.5 W / m · K or more, more preferably 1.8 W / m · K or more, and even more preferably 2 W / m · K or more. The upper limit of the thermal conductivity is not particularly limited, but may be 5.0 W / m · K or less, 4.5 W / m · K or less, or 4.0 W / m · K or less. The evaluation of thermal conductivity can be measured according to the method described in Examples described later.

A cured product obtained by thermally curing the resin composition of the present invention at 180 ° C. for 90 minutes usually exhibits a characteristic of having a low elastic modulus at 25 ° C. That is, it provides an insulating layer having a low elastic modulus. The elastic modulus is preferably 5 GPa or less, more preferably 3 GPa or less, still more preferably 1.5 GPa or less. The lower limit may be 0.1 GPa or more. The elastic modulus can be measured according to the method described in Examples described later.

A cured product obtained by thermally curing the resin composition of the present invention at 180 ° C. for 90 minutes usually exhibits a characteristic of high elongation at 25 ° C. That is, it provides an insulating layer having a high elongation rate. The elongation rate is preferably 4% or more, more preferably 4.5% or more, still more preferably 5% or more. The upper limit may be 15% or less. Elongation can be measured according to the method described in Examples described below.

The cured product obtained by thermally curing the resin composition of the present invention at 180 ° C. for 90 minutes usually gives good results in a thermal cycle test in which treatment at −50 ° C. for 30 minutes and treatment at 60 ° C. for 30 minutes are continuously performed. Is shown. That is, it exhibits a characteristic of being excellent in adhesion strength (peel strength) with a metal layer even at a low temperature. No peeling was observed between the metal layer and the insulating layer even after 100 cycles of continuous treatment at −50 ° C. for 30 minutes and treatment at 60 ° C. for 30 minutes.

In general, it is presumed that the adhesive strength between the metal layer and the cured product is weakened because the cured product shrinks at a low temperature. The resin composition of the present invention contains a component (B-1) and a component (D) in addition to the component (A) having excellent flexibility. As a result, since it is excellent in elongation and flexibility even at low temperature, the influence of shrinkage due to low temperature is suppressed, and a cured product having excellent adhesion strength at low temperature can be obtained.

The resin composition of the present invention can provide an insulating layer having excellent thermal conductivity and adhesion strength even at a low temperature. Therefore, the resin composition of the present invention forms an insulating layer of a resin composition (resin composition for an insulating layer of a semiconductor chip package) for forming an insulating layer of a semiconductor chip package and a circuit board (including a printed wiring board). It can be suitably used as a resin composition (resin composition for an insulating layer of a circuit board). Further, the resin composition of the present invention is a resin composition for encapsulating a semiconductor chip (resin composition for encapsulating a semiconductor chip) and a resin composition for forming wiring on a semiconductor chip (for forming semiconductor chip wiring). It can also be suitably used as a resin composition). Further, the resin composition of the present invention can be suitably used for adhesion of a heating element. That is, it can be suitably used as an adhesive layer between a heating element and a heat sink.

Examples of the semiconductor chip package to which the sealing layer or the insulating layer formed of the cured product of the resin composition can be applied include FC-CSP, MIS-BGA package, ETS-BGA package, and Fan-out type WLP (Wafer). Level Package), Fan-in type WLP, Fan-out type PLP (Panel Level Package), Fan-in type PLP, and the like.

Further, the resin composition includes a resin sheet, a sheet-like laminated material such as a prepreg, a solder resist, a die bonding material, a fill-in-the-blank resin, an underfill material, a MUF (Molding Under Filling) material, a component-embedded resin, and the like. It can be used in a wide range of applications where objects are used.

[Resin sheet]
The resin sheet of the present invention has a support and a resin composition layer provided on the support. The resin composition layer is a layer containing the resin composition of the present invention, and is usually formed of the resin composition.

The thickness of the resin composition layer is preferably 200 μm or less, more preferably 150 μm or less, still more preferably 100 μm or less, from the viewpoint of thinning. The lower limit of the thickness of the resin composition layer is not particularly limited, and may be, for example, 1 μm or more, 5 μm or more, 10 μm or more, and the like.

Examples of the support include a film made of a plastic material, a metal foil, and a release paper, 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 the support, the plastic material may be, for example, polyethylene terephthalate (hereinafter abbreviated as "PET") or polyethylene naphthalate (hereinafter abbreviated as "PEN"). Polyethylene such as (.); Polyethylene (hereinafter abbreviated as "PC"); Acrylic polymer such as polymethylmethacrylate (hereinafter abbreviated as "PMMA"); Cyclic polyolefin; Triacetyl cellulose (hereinafter abbreviated as "PC"). "TAC" may be abbreviated.); Polyether sulfide (hereinafter, may be abbreviated as "PES"); Polyether ketone; Polyethylene; and the like. 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 and aluminum foil. Of these, 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 surface of the support to be joined to the resin composition layer may be subjected to a mat treatment, a corona treatment, a charge suppression treatment, or the like.

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. .. Examples of commercially available release agents include "SK-1", "AL-5", "AL-7"; etc. manufactured by Lintec Corporation as alkyd resin-based mold release agents. Examples of the support with a release layer include "Lumirror T60" manufactured by Toray Industries, Inc., "Purex" manufactured by Teijin Ltd., and "Unipee" manufactured by Unitika Ltd.

The thickness of the support is preferably in the range of 5 μm to 75 μm, 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.

For the resin sheet, for example, a resin varnish in which a resin composition is dissolved in an organic solvent is prepared, the resin varnish is applied onto a support using a coating device such as a die coater, and the resin composition layer is further dried. Can be manufactured by forming the above.

Examples of the organic solvent include ketone solvents such as acetone, methyl ethyl ketone (MEK) and cyclohexanone; acetate solvents such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate; cellosolve and butyl carbitol and the like. Carbitol solvent; aromatic hydrocarbon solvent such as toluene and xylene; amide solvent such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone; and the like. 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. Drying is carried out so that the content of the organic solvent in the resin composition layer is usually 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 may include any layer other than the support and the resin composition layer, if necessary. For example, in the resin sheet, a protective film similar to the support may be provided on the surface of the resin composition layer that is not bonded to the support (that is, the surface opposite to the support). The thickness of the protective film is, for example, 1 μm to 40 μm. The protective film can suppress the adhesion and scratches of dust and the like on the surface of the resin composition layer. When the resin sheet has a protective film, the resin sheet can be used by peeling off the protective film. The resin sheet can be rolled up and stored.

The resin composition layer in the resin sheet is a layer containing the resin composition of the present invention, and is usually formed of the resin composition. Therefore, the resin sheet can be used for the same purpose as the resin composition of the present invention, and can be particularly preferably used as a resin sheet for adhering a heating element.

[Heat dissipation device]
The heat dissipation device of the present invention includes an adhesive layer formed of a cured product of the resin composition of the present invention. As one embodiment of this heat dissipation device, for example, a heating element, an adhesive layer, and a heat sink are provided in this order. Further, one embodiment has a heat sink, an adhesive layer, and a heat sink, and a heating element is embedded in the adhesive layer. The heat sink is not particularly limited as long as it has heat dissipation.

Examples of the heat dissipation device include LEDs, power modules, electrostatic chucks, and the like.

The formation of the adhesive layer is usually performed by laminating a resin sheet with a heating element and a heat sink. This lamination can be performed, for example, by removing the protective film of the resin sheet and then heat-pressing the resin sheet to the heating element from the support side to attach the resin composition layer to the heating element. Examples of the member that heat-presses the resin sheet to the heating element (hereinafter, may be 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 heating element.

The laminating of the heating element and the resin sheet may be carried out by, for example, 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. The heat crimping pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably 0.29 MPa to 1.47 MPa. 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 13 hPa or less.

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 laminating and smoothing treatment may be continuously performed using a vacuum laminator.

After laminating, the support of the resin sheet is peeled off, and the heating element and the resin composition layer are laminated so as to be bonded to the resin composition layer of the laminated body. The laminating method is as described above.

After forming the resin composition layer on the heat sink, the resin composition layer is thermally cured to form an adhesive layer. 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 usually in the range of 120 ° C. to 240 ° C. (preferably in the range of 150 ° C. to 220 ° C., more preferably 170 ° C. to 200 ° C.). The temperature is usually in the range of 5 minutes to 120 minutes (preferably 10 minutes to 100 minutes, more preferably 15 minutes to 90 minutes).

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

As described above, the heat dissipation device can be manufactured. Although the method of laminating the resin sheet and the heating element is described earlier when forming the adhesive layer, the resin sheet and the heat sink may be laminated first.

[Circuit board]
The circuit board of the present invention includes an insulating layer formed of a cured product of the resin composition of the present invention. This circuit board can be manufactured, for example, by a manufacturing method including the following steps (1) and (2).
(1) A step of forming a resin composition layer on a substrate.
(2) A step of thermally curing the resin composition layer to form an insulating layer.
The details of the method for manufacturing such a circuit board can be referred to in paragraphs 0053 to 0062 of Japanese Patent Application Laid-Open No. 2015-178620, and the contents thereof are incorporated in the present specification.

[Semiconductor chip package]
The semiconductor chip package according to the first embodiment of the present invention includes the circuit board described above and the semiconductor chip mounted on the circuit board. This semiconductor chip package can be manufactured by bonding a semiconductor chip to a circuit board.

As the bonding condition between the circuit board and the semiconductor chip, any condition can be adopted in which the terminal electrode of the semiconductor chip and the circuit wiring of the circuit board can be connected by a conductor. For example, the conditions used in flip-chip mounting of semiconductor chips can be adopted. Further, for example, the semiconductor chip and the circuit board may be bonded via an insulating adhesive.

An example of the joining method is a method of crimping a semiconductor chip to a circuit board. As the crimping conditions, the crimping temperature is usually in the range of 120 ° C. to 240 ° C., and the crimping time is usually in the range of 1 second to 60 seconds. Further, the semiconductor chip may be reflowed and bonded to the circuit board.

After joining the semiconductor chip to the circuit board, the semiconductor chip may be filled with a mold underfill material. As the mold underfill material, the above-mentioned resin composition may be used, or the above-mentioned resin sheet may be used.

The semiconductor chip package according to the second embodiment of the present invention includes a semiconductor chip and a cured product of the resin composition that encloses the semiconductor chip. In such a semiconductor chip package, the cured product of the resin composition usually functions as a sealing layer. Examples of the semiconductor chip package according to the second embodiment include a fan-out type WLP.

A method for manufacturing a semiconductor chip package such as a fan-out type WLP is as follows.
(A) Step of laminating a temporary fixing film on a base material,
(B) A process of temporarily fixing a semiconductor chip on a temporary fixing film,
(C) A step of laminating the resin composition layer of the resin sheet of the present invention on a semiconductor chip, or applying the resin composition of the present invention on a semiconductor chip and heat-curing to form a sealing layer.
(D) Step of peeling the base material and the temporary fixing film from the semiconductor chip,
(E) A step of forming a rewiring forming layer (insulating layer) on the surface from which the base material and the temporary fixing film of the semiconductor chip have been peeled off.
It includes (F) a step of forming a conductor layer (rewiring layer) on the rewiring forming layer (insulating layer), and (G) a step of forming a solder resist layer on the conductor layer. Further, the method for manufacturing a semiconductor chip package may include (H) a step of dicing a plurality of semiconductor chip packages into individual semiconductor chip packages and separating them into individual pieces.

For details of the method for manufacturing such a semiconductor chip package, the description in paragraphs 0066 to 1981 of International Publication No. 2016/035577 can be referred to, and the contents thereof are incorporated in the present specification.

The semiconductor chip package according to the third embodiment of the present invention is, for example, in the semiconductor chip package of the second embodiment, a semiconductor chip package in which a rewiring forming layer or a solder resist layer is formed of a cured product of the resin composition of the present invention. Is.

[Semiconductor device]
Examples of the semiconductor device on which the above-mentioned semiconductor chip package is mounted include electric products (for example, computers, mobile phones, smartphones, tablet devices, wearable devices, digital cameras, medical devices, televisions, etc.) and vehicles (for example, TVs). , Motorcycles, automobiles, trains, ships, aircraft, etc.).

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.

<Preparation of sample for measuring peel strength (adhesion strength)>
(1) Base treatment of inner layer circuit board Both sides of the glass cloth base material epoxy resin double-sided copper-clad laminate (copper foil thickness 18 μm, substrate thickness 0.3 mm, Panasonic R5715ES) on which the inner layer circuit is formed are manufactured by MEC. The copper surface was roughened by immersing it in CZ8100.

(2) Preparation of resin sheet PET film ("Lumilar R80" manufactured by Toray Industries, Inc.) obtained by mold-releasing the resin varnish prepared in Examples and Comparative Examples with an alkyd resin-based mold release agent ("AL-5" manufactured by Lintec Corporation). A thickness of 38 μm, a softening point of 130 ° C., hereinafter sometimes referred to as “release PET”) is applied with a die coater so that the thickness of the resin composition layer after drying is 100 μm, and the thickness is 80 ° C. to 100. A resin sheet was obtained by drying at ° C. (average 90 ° C.) for 7 minutes.

(3) Laminating of resin sheet The resin composition layer is bonded to the inner layer circuit board by using a batch type vacuum pressurizing laminator (2-stage build-up laminator "CVP700" manufactured by Nikko Materials Co., Ltd.). As described above, they were laminated on both sides of the inner layer circuit board. Lamination was carried out by reducing the pressure for 30 seconds to reduce the atmospheric pressure to 13 hPa or less, and then crimping at 120 ° C. and a pressure of 0.74 MPa for 30 seconds. Then, heat pressing was performed at 120 ° C. and a pressure of 0.5 MPa for 60 seconds.

(4) Laminating with a metal layer (copper foil) After that, the support is peeled off, and electrolysis is performed so that the resin composition layer and the roughened surface of the electrolytic copper foil are bonded to the surface of the exposed resin composition layer. Copper foil (“JTCP” manufactured by JX Nippon Mining & Metals Co., Ltd., thickness 35 μm, maximum height of roughened surface (Rz: JIS B0601-2001): 6 μm) was laminated. Then, using the above-mentioned laminator device, laminating was performed under the same conditions.

(5) Curing of Resin Composition After laminating, the resin composition layer was cured under the curing conditions of 180 ° C. for 90 minutes. In this way, a sample for measuring peel strength was obtained.

<Measurement and evaluation of peeling strength (peeling strength) of copper foil>
Make a notch in the electrolytic copper foil of the sample for peel strength measurement with a width of 10 mm and a length of 100 mm, peel off one end of this, and use a gripper (autocom type tester "AC-50C-" manufactured by TSE Co., Ltd. The peel strength was determined by grasping with SL ") and measuring the load (kgf / cm) when 20 mm was peeled off in the vertical direction at a speed of 50 mm / min at room temperature.

<Measurement of thermal conductivity of cured product>
(1) Preparation of cured product sample The resin varnish prepared in Examples and Comparative Examples was applied onto a mold release PET with a die coater so that the thickness of the resin composition layer after drying was 100 μm, and the temperature was 80 ° C. A resin sheet was obtained by drying at ~ 100 ° C. (average 90 ° C.) for 7 minutes.

The prepared resin sheet was laminated with three resin composition layers using a batch type vacuum pressurizing laminator (2-stage build-up laminator "CVP700" manufactured by Nikko Materials Co., Ltd.), and then 180 ° C. for 90 minutes. The resin composition layer was cured under the curing conditions to obtain a sample. The laminate was depressurized for 30 seconds to a pressure of 13 hPa or less, and then pressed at 120 ° C. and a pressure of 0.4 MPa for 20 seconds to obtain a cured product sample.

(2) Measurement of heat diffusion rate α For the cured product sample, the heat diffusion rate α (m ² / s) in the thickness direction of the cured product sample was measured using “ai-Phase Mobile 1u” manufactured by ai-Phase. It was measured by the temperature wave analysis method. The same sample was measured three times and the average value was calculated.

(3) Measurement of specific heat capacity Cp The cured sample is measured by raising the temperature from -40 ° C to 80 ° C at 10 ° C / min using a differential scanning calorimeter (“DSC7020” manufactured by SII Nanotechnology). The specific heat capacity Cp (J / kg · K) of the cured product sample at 25 ° C. was calculated.

(4) Measurement of Density ρ The density (kg / m ³ ) of the cured product sample was measured using an analytical balance XP105 (using a specific gravity measurement kit) manufactured by METTLER TOLEDO.

(5) Calculation of thermal conductivity λ The thermal diffusivity α (m ² / s) obtained in the above (2) to (4), the specific heat capacity Cp (J / kg · K), and the density ρ (kg / m). ³ ) was substituted into the following equation (I) to calculate the thermal conductivity λ (W / m · K).
λ = α × Cp × ρ (I)

<Measurement of elastic modulus and elongation of cured product>
The resin varnish prepared in Examples and Comparative Examples was applied on a release PTFE film (Aflex 50N: manufactured by Asahi Glass Co., Ltd.) using a bar coater, and cured at 180 ° C. for 90 minutes. The thickness of the cured product was 100 μm. Then, the PTFE film was peeled off. In accordance with Japanese Industrial Standards (JIS K7161), a tensile test was performed using a Tencilon universal tester (manufactured by A & D Co., Ltd.) at a temperature of 25 ° C (room temperature) and a tensile speed of 50 mm / min, and the elastic modulus and elongation were performed. Was measured.

<Thermal cycle test>
An evaluation substrate was prepared in the same manner as the sample for measuring peel strength, and cut into 10 cm squares. Using a small thermal shock device (“TSE-11” manufactured by ESPEC), the process of continuously performing the process a for 30 minutes at -50 ° C and the process b for 30 minutes at 60 ° C is one cycle, which is 100 cycles. The thermal cycle test to be performed was performed. After that, the state of the copper foil was confirmed, and those without peeling were evaluated as ◯, and those with peeling were evaluated as ×.

<Synthesis Example 1: Synthesis of Elastomer 1>
50 g of G-3000 (bifunctional hydroxyl group-terminated polybutadiene, number average molecular weight = 5047 (GPC method), hydroxyl group equivalent = 1798 g / eq., Solid content 100% by mass: manufactured by Nippon Soda Co., Ltd.) and Ipsol 150 in a reaction vessel. (Aromatic hydrocarbon mixed solvent: manufactured by Idemitsu Petrochemical Co., Ltd.) 23.5 g and 0.005 g of dibutyltin laurate were mixed and uniformly dissolved. When the temperature became uniform, the temperature was raised to 50 ° C., and 4.8 g of toluene-2,4-diisocyanate (isocyanate group equivalent = 87.08 g / eq.) Was added while further stirring, and the reaction was carried out for about 3 hours. The reaction is then cooled to room temperature and then 9.2 g of benzophenonetetracarboxylic dianhydride (acid anhydride equivalent = 161.1 g / eq.), 0.07 g of triethylenediamine and ethyldiglycol. 40.4 g of acetate (manufactured by Daicel) was added, the temperature was raised to 130 ° C. with stirring, and the reaction was carried out for about 4 hours. The disappearance of the NCO peak of 2250 cm ^-1 was confirmed from FT-IR. Confirmation of the disappearance of the NCO peak is regarded as the end point of the reaction, the reaction product is cooled to room temperature, filtered through a 100-mesh filter cloth, and elastomer 1 having an imide structure, a urethane structure, and a polybutadiene structure (nonvolatile content 50% by mass). ) Was obtained. The number average molecular weight was 21000.

<Synthesis Example 2: Synthesis of Elastomer 2>
80 g of polycarbonate diol (number average molecular weight: about 2,000, hydroxyl group equivalent: 1000 g / eq, solid content: 100%, "C-2015N" manufactured by Claret Co., Ltd.) and 0.01 g of dibutyl tin dilaurate in a reaction vessel, diethylene glycol monoethyl. It was uniformly dissolved in 37.6 g of ether acetate (boiling point: 217 ° C., "ethyl diglycol acetate" manufactured by Daicel Co., Ltd.). Then, the temperature of the mixture was raised to 50 ° C., and 13.9 g of toluene-2,4-diisocyanate (isocyanate group equivalent: 87.08 g / eq) was added while further stirring, and the reaction was carried out for about 3 hours. The reaction is then cooled to room temperature and then to which 14.3 g of benzophenone tetracarboxylic acid dianhydride (acid anhydride equivalent: 161.1 g / eq), 0.11 g of triethylene diamine, and diethylene glycol monoethyl ether acetate. (Boiling point: 217 ° C., "Ethyldiglycol acetate" manufactured by Daicel Co., Ltd.) 70.5 g was added, the temperature was raised to 130 ° C. with stirring, and the reaction was carried out for about 4 hours. The disappearance of the NCO peak of 2250 cm ^-1 was confirmed from FT-IR. Confirmation of the disappearance of the NCO peak is regarded as the end point of the reaction, the reaction product is cooled to room temperature, filtered through a filter cloth having a mesh opening of 100 mesh, and elastomer 2 having an imide structure, a urethane structure, and a polycarbonate structure (nonvolatile). 50% by mass) was obtained. The number average molecular weight was 11,500.

<Measurement of average particle size of thermally conductive filler>
To a 20 ml vial, add 0.01 g of a heat conductive filler, 0.2 g of a nonionic dispersant (“T208.5” manufactured by NOF CORPORATION), and 10 g of pure water, and ultrasonically disperse for 10 minutes with an ultrasonic cleaner. Was performed to prepare a sample. Next, the sample was put into a laser diffraction type particle size distribution measuring device (“SALD2200” manufactured by Shimadzu Corporation), and ultrasonic waves were irradiated for 10 minutes while circulating. After that, the ultrasonic waves were stopped, the particle size distribution was measured while maintaining the circulation of the sample, and the average particle size of the heat conductive filler was determined. The refractive index at the time of measurement was set to 1.45-0.001i.

<Measurement of specific surface area of thermally conductive filler>
The specific surface area was determined by the nitrogen BET method using an automatic specific surface area measuring device (“Macsorb HM-1210” manufactured by Mountech).

<The heat conductive filler used>
Alumina 1: A mixture of alumina with different average particle size and specific surface area, average particle size 3 μm, specific surface area 1.5 m ² / g, “KBM573” (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd. Alumina 2: A mixture of alumina with different average particle size and specific surface area, average particle size 3 μm, specific surface area 1.5 m ² / g, “KBM5783” (N-phenyl-3-amino) manufactured by Shin-Etsu Chemical Industry Co., Ltd. Surface treated with octyl trimethoxysilane)

<Example 1>
Epoxy 1 (solid content 50% by mass, number average molecular weight 21000) 14 parts, high repulsion elastic epoxy resin (Mitsubishi Chemical's "YX7400", epoxy equivalent 418 g / eq) 8 parts, ultra-flexible epoxy resin (Mitsubishi Chemical) "YX7105" manufactured by YX7105, epoxy equivalent 484 g / eq), alumina 1 180 parts, solid naphthol-based curing agent (Nittetsu Sumikin Chemical Co., Ltd. "SN485", hydroxyl group equivalent 215 g / eq, MEK solution with 50% solid content) Mix 4 parts, 6 parts of rubber particles ("Staffyloid AC3816N" manufactured by Ganz Kasei Co., Ltd.), 3 parts of curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with 5% by mass of solid content), and 30 parts of methyl ethyl ketone. , A resin varnish was prepared by uniformly dispersing with a high-speed rotary mixer.

<Example 2>
In Example 1, the amount of rubber particles (“Staffyloid AC3816N” manufactured by Ganz Kasei Co., Ltd.) was changed from 6 parts to 4 parts. A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Example 3>
In Example 1, 14 parts of elastomer 1 (solid content 50% by mass, number average molecular weight 21000) was changed to 14 parts of elastomer 2 (solid content 50% by mass, number average molecular weight 11500). A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Example 4>
In Example 1, the amount of alumina 1 was changed from 180 parts to 150 parts. A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Example 5>
In Example 1, 180 parts of alumina 1 was changed to 180 parts of alumina 2. A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Example 6>
In Example 1,
1) Change the amount of high-resilience elastic epoxy resin (Mitsubishi Chemical Corporation "YX7400", epoxy equivalent 440 g / eq) from 8 parts to 6 parts.
2) 2.7 parts of a dicyclopentadiene type epoxy resin (“HP-7200H” manufactured by DIC Corporation, an epoxy equivalent of 280 g / eq, and a MEK solution having a solid content of 75%) was added.
A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Example 7>
In Example 1,
1) Change the amount of high-resilience elastic epoxy resin (Mitsubishi Chemical Corporation "YX7400", epoxy equivalent 440 g / eq) from 8 parts to 5 parts.
2) Change the amount of ultra-flexible epoxy resin (Mitsubishi Chemical Corporation "YX7105", epoxy equivalent 480 g / eq) from 5 parts to 4 parts.
3) 5.3 parts of a dicyclopentadiene type epoxy resin (“HP-7200H” manufactured by DIC Corporation, epoxy equivalent 280 g / eq, MEK solution having a solid content of 75%) was added.
A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Example 8>
In Example 1, 6 parts of rubber particles (“Staffyloid AC3816N” manufactured by Ganz Kasei Co., Ltd.) are replaced with rubber particles (core-shell type rubber particles (“IM401-7-17” manufactured by Aika Kogyo Co., Ltd., core is polybutadiene, shell is styrene). -Divinylbenzene copolymer) was changed to 6 parts. A resin varnish was prepared in the same manner as in Example 1 except for the above items.

<Comparative Example 1>
In Example 1, 6 parts of rubber particles (“Staffyloid AC3816N” manufactured by Ganz Kasei Co., Ltd.) were not contained. A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Comparative Example 2>
In Example 1,
1) Add 17.3 parts of a dicyclopentadiene type epoxy resin (“HP-7200H” manufactured by DIC Corporation, epoxy equivalent 280 g / eq, MEK solution having a solid content of 75%).
2) 8 parts of high resilience epoxy resin (Mitsubishi Chemical "YX7400", epoxy equivalent 440 g / eq) and 5 parts of ultra-flexible epoxy resin (Mitsubishi Chemical "YX7105", epoxy equivalent 480 g / eq) It was not contained.
A resin varnish was produced in the same manner as in Example 1 except for the above items.

<Comparative Example 3>
In Example 1, 14 parts of elastomer 1 (solid content 50% by mass, number average molecular weight 21000) was added to a phenoxy resin (“YX7553BH30” manufactured by Mitsubishi Chemical Corporation, cyclohexanone: methylethylketone (MEK) having a solid content of 30% by mass) 1: 1. Solution) changed to 23 parts. A resin varnish was produced in the same manner as in Example 1 except for the above items.

The abbreviations in the table below are as follows.
Elastomer 1: Elastomer Elastomer manufactured in Synthesis Example 2: Elastomer YX7400 manufactured in Synthesis Example 2: Highly repulsive elastic epoxy resin, epoxy equivalent 418 g / eq, Mitsubishi Chemical YX7105: Ultra-flexible epoxy resin, epoxy equivalent 484 g / Eq, Mitsubishi Chemical HP-7200H: Dicyclopentadiene type epoxy resin, epoxy equivalent 280 g / eq, DIC alumina 1: Elastomer mixture with different average particle size and specific surface area, average particle size 3 μm, specific surface area 1 .5m ² / g, surface-treated with "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd. Alumina 2: A mixture of aluminas with different average particle size and specific surface area, average particle size 3 μm, specific surface area 1.5 m ² / g, surface-treated with “KBM5783” (N-phenyl-3-aminooctyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd. SN485: Solid naphthol-based curing agent, hydroxyl group equivalent 215 g / eq, Nippon Steel & Sumikin Chemical Co., Ltd. AC3816N: Rubber particles, Ganz Kasei Co., Ltd. IM401-Kai 7-17: Core-shell type rubber particles (Aika Kogyo Co., Ltd. "IM401-Kai 7-17", core is polybutadiene, shell is styrene / divinyl Benzene elastomer)
DMAP: Curing accelerator, 4-dimethylaminopyridine, MEK solution with a solid content of 5% by mass YX7553BH30: Phenoxy resin, manufactured by Mitsubishi Chemical Co., Ltd., cyclohexanone with a solid content of 30% by mass: 1: 1 solution (A) Component content: Content (mass%) when the resin component is 100% by mass.
x / y: Content of (B-1) component / Total amount of all epoxy resins contained in the resin composition Content of (C) component: Content when the non-volatile component of the resin composition is 100% by mass Amount (% by mass).

It can be seen that the insulating layer formed from the resin compositions containing the components (A) to (D) in Examples 1 to 8 is excellent in thermal conductivity and peel strength with respect to the metal layer (conductor layer). Further, in Examples 1 to 8, since the elongation is high, the flexibility is also improved, and since the elastic modulus is low, it can be seen that the occurrence of warpage is suppressed. Further, since the TCT test is a good result in Examples 1 to 8, it can be seen that the adhesion strength at a low temperature is also improved.

On the other hand, it can be seen that Comparative Example 1 containing no component (D) is inferior in elongation and TCT test as compared with Examples 1 to 8.

It can be seen that Comparative Examples 2 to 3 containing no component (A) or (B-1) are inferior in peel strength, elongation and TCT test as compared with Examples 1 to 8.

It has been confirmed that even when the components (E) and (F) are not contained, the same results as those in the above-mentioned Examples are obtained, although the degree is different.

Claims (19)

(A) Elastomer,
(B-1) Epoxy resin liquid at 25 ° C,
(C) thermally conductive filler, and (D) rubber particles,
A resin composition containing
The thermal conductivity of the cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes is 1.5 W / m · K or more and 5.0 W / m · K or less.
The component (A) is an amorphous resin component, and is
The component (C) is an inorganic filler having a thermal conductivity of 20 W / m · K or more.
The component (D) is a resin composition in the form of particles. The resin composition according to claim 1, wherein the cured product obtained by thermally curing the resin composition at 180 ° C. for 90 minutes has an elongation of 4% or more. The resin composition according to claim 1 or 2, wherein the content of the component (C) is 80% 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 3, wherein the component (C) is alumina. The resin composition according to any one of claims 1 to 4, wherein the component (C) is surface-treated with an aminosilane-based coupling agent. The resin composition according to any one of claims 1 to 5, wherein the component (B-1) is an epoxy resin which is liquid at 25 ° C. and has an epoxy equivalent of 250 g / eq or more. The resin composition according to any one of claims 1 to 6, further comprising an epoxy resin other than the components (B-2) and (B-1). Claims 1 to 7 in which x / y is 0.6 or more and 1 or less when the content of the component (B-1) is x and the total amount of all epoxy resins contained in the resin composition is y. The resin composition according to any one of the above items. (A) A component selected from a polybutadiene structure, a polysiloxane structure, a poly (meth) acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisobutylene structure, a polyisobutylene structure, and a polycarbonate structure in the molecule. The resin composition according to any one of claims 1 to 8, which is a resin having the above structure. The resin composition according to any one of claims 1 to 9, wherein the component (A) is at least one selected from a resin having a glass transition temperature of 25 ° C. or lower and a resin liquid at 25 ° C. or lower. thing. The resin composition according to any one of claims 1 to 10, wherein the component (A) has a functional group capable of reacting with the component (B-1). The component (A) has one or more functional groups selected from a hydroxyl group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group and a urethane group, according to any one of claims 1 to 11. The resin composition described. The resin composition according to any one of claims 1 to 12, wherein the component (A) has an imide structure. The resin composition according to any one of claims 1 to 13, wherein the component (A) has a phenolic hydroxyl group. The resin composition according to any one of claims 1 to 14, wherein the component (A) has a polybutadiene structure and has a phenolic hydroxyl group. The resin composition according to any one of claims 1 to 15, which is used for adhering a heating element. A resin sheet having a support and a resin composition layer provided on the support and containing the resin composition according to any one of claims 1 to 16. The resin sheet according to claim 17, which is a resin sheet for adhering a heating element. A heat radiating device comprising an adhesive layer formed of a cured product of the resin composition according to any one of claims 1 to 16.