JP2018159083A - Resin composition, resin composition sheet and method for producing resin composition sheet, resin composition sheet with metal foil, b stage sheet, semi-cured resin composition sheet with metal foil, metal base wiring board material, metal base wiring board, led light source member, and power semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which is excellent in flexibility and flowability when formed in a sheet shape, and exhibits high thermal conductivity and high insulating property when formed in a cured product; a resin composition sheet using the resin composition and a method for producing the resin composition sheet; a resin composition sheet with metal foil; a metal base wiring board material; a metal base wiring board; an LED light source member; and a power semiconductor device.SOLUTION: There is provided a resin composition which contains (A) an epoxy resin having a biphenyl skeleton, (B) an epoxy resin being a liquid at normal temperature, (C) a phenol resin and (D) an inorganic filler, contains alumina as (D) the inorganic filler, has a content of (D) the inorganic filler of 75 mass% or more in the total solid content, and an oil absorption amount of the total of (D) the contained inorganic filler of 7.5 ml/100 g or less.SELECTED DRAWING: None

Description

  The present invention includes a resin composition, a resin composition sheet and a method for producing the resin composition sheet, a resin composition sheet with a metal foil, a B stage sheet, a semi-cured resin composition sheet with a metal foil, a metal base wiring board material, The present invention relates to a metal base wiring board, an LED light source member, and a power semiconductor device.

  Most electrical devices ranging from motors and generators to printed wiring boards and IC chips include a conductor for conducting electricity and an insulating material. In recent years, these electric devices are being miniaturized rapidly, and the demand for improving the performance of insulating materials is increasing. In particular, the amount of heat generated from a high-density conductor with a reduction in size has increased remarkably, and how to dissipate heat in an insulating material has become an important issue.

  Conventionally, resin compositions containing organic resins have been widely used as insulating materials disposed in various electrical devices because of their high insulating performance and ease of molding. However, the resin composition generally has a low thermal conductivity, which is one factor that hinders heat dissipation in electrical equipment. Therefore, a resin composition having high thermal conductivity is demanded.

  As a method of achieving a high thermal conductivity of the resin composition, there is a method of filling a resin composition with an inorganic filler made of a high thermal conductive ceramic to form a composite. Examples of high thermal conductive ceramics are silica, alumina, magnesium oxide, boron nitride, aluminum nitride, and silicon nitride. In particular, alumina is often used from the viewpoints of insulation, thermal conductivity, chemical stability, and price. By filling these inorganic fillers into the resin composition, both insulation and high thermal conductivity can be achieved. It is being considered to plan.

  In addition, as another method for achieving high thermal conductivity of the resin composition, a technique for increasing the thermal conductivity of the resin itself by orderly arranging monomers having a mesogen skeleton has been studied. The mesogen skeleton refers to a rigid portion that exhibits liquid crystallinity represented by a biphenyl skeleton and the like. For example, an epoxy resin having a mesogenic skeleton causes stacking between molecules and the molecules are arranged in an orderly manner. What hardened | cured this with the hardening | curing agent can be used as an insulating material. Patent Document 1 discloses an epoxy compound exhibiting liquid crystallinity as an example of a monomer having such a mesogen skeleton.

JP 2005-206814 A

  In the resin composition filled with the above inorganic filler, in order to realize the high thermal conductivity required in recent years, it is necessary to increase the filling amount of the inorganic filler. In a resin composition highly filled with an inorganic filler, the viscosity is remarkably increased due to the interaction between the surface of the inorganic filler and the resin. Moreover, in the resin composition highly filled with the inorganic filler, the frequency with which the inorganic fillers are fitted to each other is increased, so that the fluidity is remarkably lowered. As a result, when a resin composition highly filled with an inorganic filler is applied to the adherend, voids due to poor embedding of the surface structure of the adherend or bubbles generated during coating are generated, resulting in Problems such as insulation breakdown or lack of fluidity tend to result in insufficient adhesion to the adherend and separation during processing.

  In addition, since a monomer having a mesogenic skeleton is generally easy to crystallize and is solid at room temperature, it is difficult to handle compared with a general-purpose resin. Furthermore, when the monomer having a mesogen skeleton is regularly arranged to increase the thermal conductivity of the resin composition, if the inorganic filler is highly charged, the fluidity is remarkably lowered, and the above-mentioned difficulty caused by the inorganic filler Due to the added properties, molding becomes more difficult.

  Under such circumstances, the present invention provides a resin composition that is excellent in flexibility and fluidity when formed into a sheet shape, and exhibits high thermal conductivity and high insulation when formed into a cured product. Let it be an issue. In addition, a resin composition sheet using the same, a method for producing the resin composition sheet, a resin composition sheet with metal foil, a B stage sheet, a semi-cured resin composition sheet with metal foil, a metal base wiring board material, and a metal base It is an object to provide a wiring board, an LED light source member, and a power semiconductor device.

  As a result of intensive studies to solve the above problems, the present inventors have reached the present invention. That is, the present invention is as follows.

<1> (A) An epoxy resin having a biphenyl skeleton, (B) an epoxy resin that is liquid at room temperature, (C) a phenol resin, and (D) an inorganic filler, and the (D) inorganic filler It contains alumina, the content of the (D) inorganic filler is 75% by mass or more in the total solid content, and the oil absorption amount of the whole (D) inorganic filler contained is 7.5 ml / 100 g or less. Resin composition.

<2> The resin composition according to <1>, including a phenol resin having a structural unit represented by the following general formula (I) as the (C) phenol resin.

In general formula (I), R ¹ represents an alkyl group, an aryl group, or an aralkyl group, R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group, m Represents an integer of 0 to 2, and n represents a number of 1 to 10.

<3> The inorganic filler (D-1) includes an inorganic filler group (D-1) having a particle diameter D50 of 5 μm or more and 100 μm or less corresponding to 50% cumulative from the small particle size side of the weight cumulative particle size distribution; Is 1/2 or less of the inorganic filler group (D-1), the inorganic filler group (D-2) is 1 μm or more and 10 μm or less, and D50 is 1/2 of the inorganic filler group (D-2). And an inorganic filler group (D-3) of 0.1 μm or more and 5 μm or less,
The ratio of the inorganic filler group (D-1), (D-2) and (D-3) to the total amount of the (D) inorganic filler is 40% by mass to 90% by mass and 5% by mass, respectively. 40 mass% or less, 1 mass% or more and 30 mass% or less (however, the total mass% of the inorganic filler group (D-1), (D-2) and (D-3) is 100 mass%). The resin composition according to <1> or <2>.

<4> The inorganic filler (D-3) is 0.5% by mass of spherical alumina having a particle diameter D50 of 0.1 μm or more and 1 μm or less corresponding to 50% accumulated from the small particle size side of the weight cumulative particle size distribution. The resin composition according to <3>, which is contained in the range of 15% by mass or less.

<5> The epoxy resin that is liquid at room temperature (B) includes a liquid epoxy resin having a skeleton derived from at least one selected from bisphenol A, bisphenol F, and dihydroxynaphthalene, and is a total epoxy resin / total phenol resin. The resin composition according to any one of <1> to <4>, wherein an equivalent ratio of is from 0.8 to 1.1.

<6> A resin composition sheet obtained by molding the resin composition according to any one of <1> to <5> into a sheet shape.

<7> Metal foil,
A resin composition layer formed from the resin composition according to any one of <1> to <5> provided on the metal foil;
A resin composition sheet with a metal foil.

<8> A B stage sheet which is a semi-cured product of the resin composition sheet according to <6>.

<9> A semi-cured resin composition sheet with a metal foil, which is a semi-cured product of the resin composition sheet with a metal foil according to <7>.

<10> Metal foil, metal plate,
A thermally conductive insulating layer that is a cured product of the resin composition according to any one of <1> to <5>, provided between the metal foil and the metal plate;
Metal base wiring board material having

<11> Thermal conductivity that is a cured product of the resin composition according to any one of <1> to <5>, between the wiring layer, the metal plate, and the wiring layer and the metal plate. An insulating layer;
Metal base wiring board having

<12> The resin composition sheet according to <6>, the resin composition sheet with metal foil according to <7>, the B stage sheet according to <8>, and the semi-cured material according to <9> LED light source member manufactured using any one of the resin composition sheet with metal foil, the metal base wiring board material according to <10>, and the metal base wiring board according to <11>. .

<13> The resin composition sheet according to <6>, the resin composition sheet with metal foil according to <7>, the B stage sheet according to <8>, and the semi-cured material according to <9> A power semiconductor device manufactured using any one of the resin composition sheet with metal foil, the metal base wiring board material according to <10>, and the metal base wiring board according to <11>. .

<14> The resin composition according to any one of <1> to <5> containing (C) a phenolic resin derived from dihydroxybenzene is applied onto a substrate, and the dihydroxybenzene is a monomer in the sheet. The manufacturing method of the resin composition sheet | seat including the process shape | molded in a sheet form by making it dry on the conditions which remain | survive in this state.

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition which is excellent in the softness | flexibility and fluidity | liquidity when it is set as a sheet | seat shape, and shows high heat conductivity and high insulation when it is set as a hardened | cured material can be provided. In addition, a resin composition sheet using the same, a method for producing the resin composition sheet, a resin composition sheet with metal foil, a B stage sheet, a semi-cured resin composition sheet with metal foil, a metal base wiring board material, and a metal base A wiring board, an LED light source member, and a power semiconductor device can be provided.

It is a schematic sectional drawing which shows an example of a structure of the power semiconductor device comprised using the hardened | cured material of the resin composition concerning this invention. It is a schematic sectional drawing which shows an example of a structure of the power semiconductor device comprised using the hardened | cured material of the resin composition concerning this invention. It is a schematic sectional drawing which shows an example of a structure of the power semiconductor device comprised using the hardened | cured material of the resin composition concerning this invention. It is a schematic sectional drawing which shows an example of a structure of the LED light bar comprised using the hardened | cured material of the resin composition concerning this invention. It is a schematic sectional drawing which shows an example of a structure of the LED light bulb comprised using the hardened | cured material of the resin composition concerning this invention. It is a schematic sectional drawing which shows an example of a structure of the LED light bulb comprised using the hardened | cured material of the resin composition concerning this invention. It is a schematic sectional drawing which shows an example of a structure of the LED board comprised using the hardened | cured material of the resin composition concerning this invention.

In the present invention, the term “process” is not limited to an independent process, and is included in the term if the intended action of the process is achieved even when it cannot be clearly distinguished from other processes.
In the present specification, a numerical range indicated by using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively.
Furthermore, in this specification, the amount of each component in the composition is the sum of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. Means quantity.

<Resin composition>
The resin composition of the present invention includes (A) an epoxy resin having a biphenyl skeleton, (B) an epoxy resin that is liquid at room temperature, (C) a phenol resin, and (D) an inorganic filler, Alumina is included as the inorganic filler, the content of the (D) inorganic filler is 75% by mass or more in the total solid content, and the oil absorption amount of the whole (D) inorganic filler contained is 7.5 ml / 100 g or less. The resin composition of the present invention may further contain other components as necessary.

(A) Use of an epoxy resin having a biphenyl skeleton is preferable from the viewpoint of thermal conductivity because the thermal conductivity of the resin is higher than when a general-purpose epoxy resin is used. In addition, (B) by including an epoxy resin that is liquid at normal temperature, flexibility in an uncured state or a semi-cured state is imparted, and (A) an epoxy resin having a biphenyl skeleton is used alone as an epoxy resin. This is preferable because it is easier to improve the crosslink density than in the case.
Moreover, the balance of thermal conductivity and moisture resistance is improved by including alumina as the inorganic filler (D). And by making the oil absorption amount of the whole (D) inorganic filler contained in the resin composition 7.5 ml / 100 g or less, more inorganic filler can be filled in the resin composition sheet, Both high thermal conductivity and fluidity can be achieved. The smaller the amount of oil absorption of the entire inorganic filler, the better the moldability and fluidity at the same time even with a higher filling amount.
Each component will be described below.

〔Epoxy resin〕
The resin composition of the present invention contains at least (A) an epoxy resin having a biphenyl skeleton and (B) an epoxy resin that is liquid at room temperature as an epoxy resin. You may contain another epoxy resin suitably as needed.

(A) Epoxy resin having a biphenyl skeleton (A) The epoxy resin having a biphenyl skeleton is not particularly limited as long as it includes at least one biphenyl skeleton in the molecular chain. (A) Since the epoxy resin having a biphenyl skeleton has a mesogen skeleton, it is possible to increase the higher order structure of the resin and realize high heat dissipation.
Examples of the biphenyl skeleton include structures represented by the following general formula (II).

In general formula (II), R ^{11 to} R ¹⁸ each independently represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms.

  The biphenyl skeleton represented by the general formula (II) has a feature that the orientation of the epoxy resin in the z-axis direction (perpendicular to the molecular structure plane) is easy. Such characteristics are advantageous for lowering the thermal resistance after curing of the epoxy resin composition, and as a result, increase the heat dissipation of the cured product and give high heat dissipation.

  Examples of the epoxy resin having a biphenyl skeleton represented by the general formula (II) include compounds represented by the following general formula (III).

In the general formula (III), R ^{11 to} R ¹⁸ each independently represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms. n represents an integer of 0 to 3.

Examples of the substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms represented by R ^{11 to} R ¹⁸ include a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, and an isobutyl group. be able to. Among these, R ^{11 to} R ¹⁸ are preferably a hydrogen atom or a methyl group from the viewpoint of thermal conductivity.

  N in the general formula (III) is preferably 0 to 2, more preferably 0 or 1, and particularly preferably 0 from the viewpoint of fluidity.

As the compound represented by the general formula (III), R ¹¹ , R ¹³ , R ¹⁶ , and R ¹⁸ are methyl groups, R ¹² , R ¹⁴ , R ¹⁵ , and R ¹⁷ are hydrogen atoms, and n = 0. "YX4000H" (trade name, manufactured by Mitsubishi Chemical Corporation) mainly composed of 4,4'-bis (2,3-epoxypropoxy) -3,3 ', 5,5'-tetramethylbiphenyl; R ¹¹ , R ¹³ , R ¹⁶ , and R ¹⁸ are methyl groups, R ¹² , R ¹⁴ , R ¹⁵ , and R ¹⁷ are hydrogen atoms, 4,4′-bis (2,3-epoxypropoxy)-, where n = 0 A compound mainly composed of 3,3 ′, 5,5′-tetramethylbiphenyl, and 4,4′-bis (2,3-epoxypropoxy) biphenyl in which R ^{11 to} R ¹⁸ are hydrogen atoms and n = 0 "YL, which is a mixture with a compound mainly composed of 121H "(Mitsubishi Chemical Co., Ltd., trade name); available etc. in the market. Moreover, it is preferable that it is an epoxy resin containing a tetramethyl body from a viewpoint of the moldability improvement by low melting | fusing point.

  (A) The epoxy equivalent of the epoxy resin having a biphenyl skeleton is preferably 170 g / eq to 540 g / eq, more preferably 170 g / eq to 360 g / eq, and 170 g / eq to 180 g / eq. More preferably.

  From the viewpoint of sufficiently obtaining the effects of the present invention, the content of the epoxy resin (A) having a biphenyl skeleton is preferably 70% by mass or more, more preferably 80% by mass or more of the entire epoxy resin, 90% It is especially preferable to set it as mass% or more.

-(B) Epoxy resin that is liquid at room temperature The resin composition of the present invention includes (B) an epoxy resin that is liquid at room temperature. (B) By containing a liquid epoxy resin at normal temperature, good flexibility can be imparted when the resin composition sheet is handled at normal temperature.
In the present invention, “liquid at normal temperature” means a liquid that has fluidity at room temperature for 6 hours or more even when the crystallized resin is once melted by heating and then returned to normal temperature (25 ° C.). To do. From the viewpoint of imparting flexibility, it is particularly preferable that the viscosity at room temperature is 100 mPa · s to 10000 mPa · s.

  (B) Examples of epoxy resins that are liquid at room temperature include bisphenol A type epoxy resins, bisphenol F type epoxy resins, and dihydroxynaphthalene type epoxy resins. “Epicoat 828” (trade name, manufactured by Mitsubishi Chemical Corporation) as the bisphenol A type epoxy resin, “YDF8170” (trade name, manufactured by Toto Kasei Co., Ltd.) as the bisphenol F type epoxy resin, and ortho-type novolak Epoxidized “Epicoat 152” (trade name, manufactured by Mitsubishi Chemical Corporation), “HP-4032D” (trade name, manufactured by DIC Corporation) as a dihydroxynaphthalene type epoxy resin, and “half-hydrogenated biphenyl type epoxy resin” YL6800 "(trade name, manufactured by Mitsubishi Chemical Corporation).

  From the viewpoints of reactivity and curability, a liquid epoxy resin obtained by allowing epichlorohydrin to act on a phenolic hydroxyl group is preferred, and in particular, considering the properties of the cured product when combined with an epoxy resin having a biphenyl skeleton, a bisphenol F type epoxy resin Dihydroxynaphthalene type epoxy resin or bisphenol A type epoxy resin is preferable. These (B) normal temperature liquid epoxy resins may be used alone or in combination of two or more.

  (B) The content of the epoxy resin that is liquid at room temperature is preferably 1% by mass or more and 30% by mass or less of the entire epoxy resin from the viewpoint of imparting flexibility, and 5 from the viewpoint of coexistence with thermal conductivity. It is preferable to set it as mass% or more and 20 mass% or less.

-Other epoxy resin Moreover, in this invention, the epoxy resin other than the epoxy resin which has said (A) biphenyl frame | skeleton and said (B) liquid epoxy resin at normal temperature as an epoxy resin is impaired. It is possible to use in the range which is not. Examples of the other epoxy resins include epoxy resins that are generally used in epoxy resin compositions for sealing.

  Examples of other epoxy resins that can be used in combination include phenols such as phenol novolac type epoxy resins, orthocresol novolac type epoxy resins, phenols such as cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, and / or α-. Epoxy novolak resin obtained by condensation or cocondensation of naphthols such as naphthol, β-naphthol, dihydroxynaphthalene and the like with compounds having an aldehyde group such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde in the presence of an acidic catalyst. Can be listed.

  In addition, diglycidyl ethers such as bisphenol A, bisphenol F, bisphenol S, bisphenol A / D; epoxidized products of phenol aralkyl resins synthesized from phenols and / or naphthols and dimethoxyparaxylene or bis (methoxymethyl) biphenyl; Glycidyl ester type epoxy resin obtained by reaction of polybasic acid such as stilbene type epoxy resin, hydroquinone type epoxy resin, phthalic acid or dimer acid and epichlorohydrin; glycidylamine obtained by reaction of polyamine such as diaminodiphenylmethane or isocyanuric acid and epichlorohydrin Type epoxy resin; dicyclopentadiene type epoxy resin which is an epoxidized product of co-condensation resin of cyclopentadiene and phenols; hydroxynaphthalene and Or epoxidized product such as dihydroxynaphthalene dimer; triphenolmethane type epoxy resin; trimethylolpropane type epoxy resin; terpene modified epoxy resin; linear aliphatic obtained by oxidizing olefinic bond with peracid such as peracetic acid Epoxy resin; alicyclic epoxy resin; sulfur atom-containing epoxy resin; and epoxy resins obtained by modifying these epoxy resins with silicone, acrylonitrile, butadiene, isoprene-based rubber, polyamide-based resin, or the like.

[(C) Phenolic resin]
(C) The phenol resin is preferably a polyfunctional phenol, and examples thereof include phenol novolak, phenol aralkyl, naphthol aralkyl, biphenylene aralkyl, dicyclopentadiene phenol, catechol novolak, and resorcinol novolak. A phenol resin may be used individually by 1 type or in combination of 2 or more types.

  Since the polyfunctional phenol resin has a small hydroxyl equivalent, the ratio of the epoxy resin can be increased in the resin composition using the polyfunctional phenol resin when the filling rate of the same inorganic filler is used. Therefore, when (A) an epoxy resin having a biphenyl skeleton is used, more arrangement structures can be formed by increasing the mesogen ratio in the resin composition, and the thermal conductivity of the resin itself is increased. As a result, the thermal conductivity of the cured product of the resin composition is increased.

  In particular, from the viewpoint of thermal conductivity and heat resistance, a resorcinol type novolak is preferable, and a phenol resin having a structural unit represented by the following general formula (I) is particularly preferable.

In general formula (I), R ¹ represents an alkyl group, an aryl group, or an aralkyl group, R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group, m Represents an integer of 0 to 2, and n represents a number of 1 to 10.

The alkyl group, aryl group, and aralkyl group represented by R ¹ , R ^2, and R ³ may further have a substituent if possible. Examples of the substituent include an alkyl group, an aryl group, a halogen atom, An atom, a hydroxyl group, etc. can be mentioned.

R ² and R ³ are preferably a hydrogen atom, an alkyl group, or an aryl group from the viewpoint of storage stability and thermal conductivity, and are preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or 3 to 6 carbon atoms. Of the aryl group is more preferable, and a hydrogen atom is more preferable.

M in the general formula (I) is an integer of 0 to 2, and when m is 2, two R ¹ may be the same or different. In the present invention, m is preferably 0 or 1 and more preferably 0 from the viewpoint of thermal conductivity.

The phenol resin having the structural unit represented by the general formula (I) includes a partial structure derived from resorcinol as a phenolic compound, but further includes at least one partial structure derived from a phenolic compound other than resorcinol. May be.
Here, the partial structure derived from the phenolic compound means a monovalent or divalent group constituted by removing one or two hydrogen atoms from the benzene ring portion of the phenolic compound. The position where the hydrogen atom is removed is not particularly limited.

  In the present invention, partial structures derived from phenolic compounds other than resorcinol include phenol, cresol, catechol, hydroquinone, 1,2,3-trihydroxybenzene, 1 from the viewpoint of thermal conductivity, adhesiveness, and storage stability. , 2,4-trihydroxybenzene, and a partial structure derived from at least one selected from 1,3,5-trihydroxybenzene, and the partial structures derived from these may be used alone or in combination of two kinds. It may be included in combination. In particular, a partial structure derived from dihydroxybenzene such as catechol and hydroquinone is more preferable from the viewpoint of crosslinkability and heat resistance.

  Further, the content ratio of the partial structure derived from resorcinol in the phenol resin is not particularly limited, but from the viewpoint of thermal conductivity and storage stability, the content ratio of the partial structure derived from resorcinol to the total mass of the phenol resin is 55. It is preferably at least mass%, more preferably at least 80 mass%, and even more preferably at least 90 mass%.

  Specifically, the phenol resin having the structural unit represented by the general formula (I) in the present invention has a partial structure represented by any one of the following general formulas (Ia) to (If). A phenol resin containing a compound is preferable.

  In the general formula (Ia) to general formula (If), i and j represent the content ratio (% by mass) of structural units derived from the respective phenolic compounds, i is 5% by mass to 30% by mass, and j is It is 70 mass%-95 mass%, and the sum total of i and j is 100 mass%.

  The phenol resin having the structural unit represented by the general formula (I) can be synthesized, for example, by the method described in JP-A-2005-206814.

  Moreover, when using the phenol resin which has a structural unit represented by the said general formula (I), it is preferable that the monomer of a polyfunctional phenolic compound is included in a resin composition, and it is preferable from a viewpoint of melting | fusing point and a hydroxyl equivalent. In particular, it is preferable that dihydroxybenzene such as catechol, resorcinol, hydroquinone or the like is contained in a monomer state. These phenolic compounds as monomers may be contained singly or in combination of two or more. From the viewpoint of melting point, it is preferable to contain catechol or resorcinol, and from the viewpoint of reactivity and crosslinkability, it is more preferable to include resorcinol.

  These monomers generally have a lower melt viscosity than the phenol resin, and by adding this to the resin composition, the entire resin composition has a low viscosity when heated or melted, and tends to impart fluidity to the resin composition. In addition, by remaining as a monomer in the resin composition sheet, when the resin composition is applied to produce a resin composition sheet, it corresponds to a process necessary for production such as winding of the resin composition sheet. Therefore, the flexibility of the resin composition sheet can be improved. The inclusion of these monomers is particularly useful when (B) the epoxy resin that is liquid at room temperature cannot be sufficiently added due to thermal conductivity limitations.

  The proportion of the total mass of dihydroxybenzene in the total mass of the (C) phenolic resin and the monomer dihydroxybenzene is 5% by mass to 80% by mass, so that the viscosity of the resin composition (including the solvent) The liquid viscosity and the viscosity at the time of melting after the solvent evaporates can be effectively reduced to obtain good moldability, and is preferably 10% by mass to 50% by mass. From the viewpoint of achieving both crosslinkability and heat resistance, the content is more preferably 15% by mass to 40% by mass.

  (C) The hydroxyl equivalent of the phenol resin is preferably 58 g / eq to 200 g / eq, more preferably 60 g / eq to 100 g / eq, and still more preferably 60 g / eq to 70 g / eq. . In addition, this hydroxyl equivalent is measured including a phenolic compound, when a phenol resin contains the phenolic compound as a monomer.

  In this invention, the hardening accelerator may be included in order to accelerate | stimulate reaction etc. with an epoxy resin, a phenol resin, and a phenolic compound. Although the kind and compounding quantity of a hardening accelerator are not specifically limited, An appropriate thing can be selected from viewpoints, such as reaction rate, reaction temperature, and storage property. Specific examples of the accelerator include imidazole compounds, organophosphorus compounds, tertiary amines, and quaternary ammonium salts. These may be used alone or in combination of two or more.

  In the present invention, the equivalent ratio is obtained by subliming or evaporating the phenolic compound in the monomer state together with the solvent in the process of molding the resin composition into a sheet shape, so that the resin composition containing the solvent contains In comparison, the epoxy group ratio is increased. When selecting a curing catalyst that does not cause homopolymerization between epoxy groups, the equivalent ratio is preferably 0.9 to 1.1, and when an imidazole compound that also causes homopolymerization between epoxy resins is used. , 0.8 to 1.0 is preferable because unreacted hydroxyl groups are hardly formed and heat resistance is improved.

[(D) inorganic filler]
In the resin composition of the present invention, the inorganic filler contains alumina from the viewpoint of a balance between thermal conductivity and moisture resistance, and further uses aluminum nitride, boron nitride, silicon nitride, magnesium oxide, or the like as necessary. Also good.

  The crystal type of alumina is not particularly limited and may be any of α-type, γ-type, δ-type, and θ-type, and has high thermal conductivity, high melting point, high mechanical strength, and electrical insulation. Α-alumina is preferable from the viewpoint of superiority. Moreover, in order to improve fluidity, it is good also as a spherical form by spraying (alpha) -alumina.

  In addition, from the viewpoint of thermal conductivity, nitride fillers such as aluminum nitride, boron nitride, and silicon nitride are excellent, so that the nitride filler and alumina can be used in combination depending on the desired thermal conductivity.

  The inorganic filler may be a group of inorganic fillers having a single particle size distribution, but from the viewpoint of the filling properties of the inorganic filler, 75% by mass of the inorganic filler group having a single particle size distribution. It is difficult to fill the above. Therefore, it is preferable to combine two or more inorganic filler groups having different particle size distributions, and it is more preferable to combine three or more inorganic filler groups having different particle size distributions.

  Regarding the mixing ratio, for example, in the case of applying three types of inorganic filler groups having different particle size distributions, the particle size D50 corresponding to 50% cumulative from the small particle size side of the weight cumulative particle size distribution is Inorganic filler group (D-1) of 5 μm or more and 100 μm or less, D50 is 1/2 or less of inorganic filler group (D-1), inorganic filler group (D-2) of 1 μm or more and 10 μm or less, and D50 is 1/2 or less of the inorganic filler group (D-2) and includes an inorganic filler group (D-3) of 0.1 μm or more and 5 μm or less, and (D) with respect to the total amount of the inorganic filler The proportions of the inorganic filler groups (D-1), (D-2), and (D-3) are 40% by mass to 90% by mass, 5% to 40% by mass, and 1% by mass to 30%, respectively. % By mass or less (however, inorganic filler groups (D-1), (D-2) and (D-3 The total weight percent of it is preferable to fill in a proportion of 100 mass%).

  Moreover, when using an inorganic filler having a wide particle size distribution, it may be difficult to clearly separate the particle size distribution after mixing. In such a case, after determining the maximum particle size in consideration of the film thickness of the resin composition sheet to be designed, when drawing the weight cumulative particle size distribution, the large particle size side meets the conventional knowledge such as the Fuller curve. It is preferable to design the particle size distribution.

Further, the resin composition is a spherical alumina having a particle diameter D50 corresponding to 50% cumulative from the small particle diameter side of the weight cumulative particle size distribution of 0.1 μm to 1 μm, and part of the inorganic filler group (D-3) Is preferably replaced by a specific amount (preferably 0.5% by mass or more and 15% by mass or less), since the fitting between the inorganic fillers contained in the resin composition can be suppressed and a lubricating effect can be obtained.
Because of this effect, α-alumina with high thermal conductivity and non-spherical fillers such as aluminum nitride, boron nitride, and silicon nitride can be used to suppress fitting between inorganic fillers. A resin composition filled with more filler can be produced. In addition, in the resin composition sheet and the resin composition sheet with metal foil formed using the resin composition of the present invention, the air bubbles formed at the time of production and the pores with the adherend interface are good when these sheets are attached. Therefore, the dielectric breakdown resistance is improved. Furthermore, since the fluidity can follow the shape of the adherend satisfactorily, the adhesion to the adherend is also good.

Moreover, the average particle diameter and the maximum particle diameter of the inorganic filler group (D-1) are limited by the target film thickness of the resin composition sheet. When there is no other restriction, from the viewpoint of thermal conductivity, the average particle diameter of the inorganic filler group (D-1) is preferably as large as possible. However, it is preferable that the thickness of the resin composition sheet is as thin as possible within a range that the insulating property allows from the viewpoint of thermal resistance. From the viewpoint of insulation, the maximum particle size of the inorganic filler is preferably 7/8 or less, more preferably 2/3 or less, and more preferably 1/2 or less of the film thickness of the resin composition sheet. More preferably.
Therefore, the particle diameter D50 of the inorganic filler group (D-1) is preferably 5 μm or more and 100 μm or less in view of the film thickness of a general resin composition sheet. From the viewpoint of property, it is more preferably 10 μm or more and 75 μm or less, and further preferably 10 μm or more and 45 μm or less.

  In the present invention, (D) the particle diameter D50 of the inorganic filler is measured using a laser diffraction method, and corresponds to the particle diameter at which the cumulative weight size distribution is drawn from the small particle diameter side and the weight accumulation is 50%. The particle size distribution measurement using the laser diffraction method can be performed using a laser diffraction scattering intensity distribution measurement device (for example, LS230 manufactured by Beckman Coulter, Inc.).

  In addition, in the above description, a combination of suitable particle sizes of the inorganic filler has been described. However, since there is an influence on the shape of the particles and the way the particle size distribution spreads, the combination of the particle sizes is not limited to a simple combination. It is preferable to adjust the mixing ratio in order to obtain fluidity and moldability. In order to find a suitable mixing ratio suitable for each inorganic filler, it is better to change the mixing ratio mainly around the mixing ratio determined in the above range and determine the optimal mixing ratio by measuring the oil absorption amount by the following method. .

(D) The content of the inorganic filler is 75% by mass or more in the total solid content of the resin composition, preferably 85% by mass or more and 98% by mass or less, and has a thermal conductivity, electrical insulation, and resin. From the viewpoint of the flexibility of the composition sheet, it is more preferably 90% by mass or more and 95% by mass or less.
In addition, solid content in a resin composition means the residue which removed the volatile component from the component which comprises a resin composition.

  Moreover, the oil absorption amount of the whole (D) inorganic filler contained in the resin composition is 7.5 ml / 100 g or less. By setting the oil absorption amount of the entire inorganic filler to 7.5 ml / 100 g or less, more inorganic filler can be filled in the resin composition sheet, and both high thermal conductivity and fluidity can be achieved. . The smaller the total amount of oil absorption of the inorganic filler, the better the moldability and fluidity at a higher filling amount. When the amount is 7 ml / 100 g or less, the fit between the inorganic fillers is reduced, and the molding is better. It is preferable because it can be made 6.5ml / 100g or less, and the density is more stable near the design density, and it is more preferable because the insulation is improved, and if it is made 6ml / 100g or less, the filling amount can be increased and the thermal conductivity is improved. It is further preferable because it can be done.

Below, the measuring method of the oil absorption amount in this invention is described.
(1) 0.3 g of ED-113 (density 0.94 g / ml, manufactured by Enomoto Kasei Co., Ltd.) as a dispersant in a plastic bag “Unipack E-4” (manufactured by Nippon Production Co., Ltd.) Weigh 50 g of the inorganic filler of the ratio.
(2) Tighten the chuck and squeeze the bag so that ED-113 fits into the filler.
(3) Dioctyl phthalate (DOP, density 0.988 g / ml) is added in an amount of about 0.2 to 0.3 g, and the bag is rubbed to acclimate each time. The end point is the point at which the filler in the bag is integrated and the surface is tapped, and the oil absorption is obtained by the following formula.
Under the present circumstances, it measured by AA-18 (made by Sumitomo Chemical Co., Ltd.) 31.5g, AA-3 (made by Sumitomo Chemical Co., Ltd.) 11.25g, AA-04 (made by Sumitomo Chemical Co., Ltd.) 7.25g as a filler. In this case, it is recommended that 2.8 g of DOP is added and the feel and appearance of the blended product (oil absorption amount: 6.2 ml / 100 g) are used as a measure of the end point. Further, when the surface area of the filler is large, it may take time for the DOP to become familiar with the filler. In that case, it is possible to shorten the time until it is adapted by increasing the addition amount of ED-113. It is possible to prevent the end point from being erroneously determined and excessively adding DOP.

  (Oil absorption amount of filler mixture) [ml / 100 g] = {(weight of ED-113) / (density of ED-113) + (weight of DOP) / (density of DOP)} [ml] / (filler Total weight [g]) × 100

  In addition, when the filling amount of the inorganic filler is 3 volume% to 10 volume%, preferably 6 volume% to 10 volume% less than the upper limit volume fraction calculated from the oil absorption amount in the following formula, Since there is more margin than the filling limit of the filler, the resin-specific characteristics such as adhesiveness are exhibited. The larger the difference between the upper limit volume fraction and the actual inorganic filler filling amount, the better the margin in the manufacturing process is. However, if the difference is too large, fluidity may become excessive and defects may occur. is there. When the fluidity becomes excessive, the fluidity can be adjusted by increasing the inorganic filler or adding a high molecular weight component.

  (Upper volume fraction) [volume%] = (volume of filler 100 g) [ml / 100 g] / {(volume of filler 100 g) [ml / 100 g] + (oil absorption of filler mixture) [ml / 100 g ] × 100

However,
(Volume of filler 100 g) [ml / 100 g] = 100 / (average density of filler) = 100 / Σ {(volume fraction of i-th filler) × (density of i-th filler)}

  The total oil absorption amount of the inorganic filler contained in the resin composition sheet or its semi-cured product or cured product is obtained by measuring the oil absorption amount of the ash content of the resin composition sheet or its semi-cured product or cured product. Can be confirmed. The ash content of the resin composition sheet or semi-cured product or cured product thereof can be recovered by placing the resin composition sheet or semi-cured product or cured product thereof in a crucible and burning the resin content. The combustion temperature in that case should just be the range which inorganic fillers do not sinter and chemically change, and when especially the component which sinters at low temperature is not included, it is made to burn for about 10 minutes-30 minutes at 500 to 800 degreeC. It is preferable. The identification of the inorganic filler component can be inferred from a resin composition sheet or a combination of energy-dispersed X-ray analysis and X-ray diffraction of a semi-cured product or a cured product.

[Other additives]
The resin composition of the present invention preferably contains a silane coupling agent. The silane coupling agent plays a role of forming a covalent bond (corresponding to the binder agent) between the surface of the inorganic filler and the organic resin surrounding the inorganic filler, and functions to efficiently transfer heat, and further to infiltrate moisture. This also contributes to improved insulation reliability.

  In general, commercially available silane coupling agents can be used, but considering the compatibility with epoxy resins and phenol resins and the reduction of thermal conduction deficiency at the interface between the resin layer and the inorganic filler layer, the terminal is epoxy. It is preferable to use a silane coupling agent having a group, a secondary or higher amine skeleton, a mercapto group, a ureido group, or a hydroxyl group.

  Examples of silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2 -(3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptotriethoxysilane, 3-ureidopropyltriethoxysilane, etc. Silane coupling agent oligomers (manufactured by Hitachi Chemical Coated Sand Co., Ltd.) represented by SC-6000KS2 can be used. These silane coupling agents can be used alone or in combination of two or more.

  Moreover, the resin composition of this invention may contain a dispersing agent. As the dispersant, a dispersant effective for dispersing alumina can be used without any particular limitation. As the dispersant, for example, Ajinomoto Finetech Co., Ltd. Ajisper series, Enomoto Kasei Co., Ltd. HIPLAAD series, Kao Corporation homogenol series, and the like can be mentioned. Two or more kinds of these dispersants can be used in combination.

  Furthermore, you may add high molecular weight components, such as a prepolymer of an acrylic rubber, an acrylic elastomer, and an epoxy resin, to the resin composition of this invention. By including an appropriate amount of these high molecular weight components, the physical properties of the resin composition sheet can be improved, such as improvement of coating properties, control of fluidity, and imparting stress relaxation properties.

  Moreover, you may contain the organic solvent of a suitable boiling point according to shaping | molding processes, such as a drying temperature when manufacturing the below-mentioned resin composition sheet | seat, time, and a film thickness. As the organic solvent, a commonly used organic solvent can be used. Specific examples include alcohol solvents, ether solvents, ketone solvents, amide solvents, aromatic hydrocarbon solvents, ester solvents, nitrile solvents, and the like. For example, methyl isobutyl ketone, dimethylacetamide, dimethylformamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, γ-butyrolactone, sulfolane, cyclohexanone, methyl ethyl ketone can be used.

  These organic solvents may be used alone or as a mixed solvent using two or more kinds in combination. At this time, it is preferable to use a material having a boiling point of 130 ° C. or higher because drying proceeds mildly and a leveling action is generated on the surface. In particular, cyclopentanone and cyclohexanone can be particularly preferably used from the viewpoint of the balance between boiling point and solubility.

[Method for producing resin composition]
The resin composition of the present invention is produced by mixing, dissolving, and dispersing the above-described components. Mixing and dispersion are performed by known methods. Specifically, devices such as a homomixer, two rolls, three rolls, a planetary mixer, a ball mill, and a bead mill can be used alone or in combination.

[Use of resin composition, etc.]
The resin composition of the present invention achieves both high thermal conductivity and excellent fluidity. Moreover, the resin cured material formed using the resin composition of this invention has high heat conductivity, and is excellent in insulation. Therefore, it can be expected that LED light source members and power semiconductor devices will be developed into heat dissipation materials.

<Resin composition sheet>
The resin composition sheet of the present invention is obtained by molding the resin composition into a sheet shape. Specifically, the resin composition is applied on a substrate and dried. The resin composition sheet of the present invention is preferably a so-called B stage sheet made of a semi-cured resin composition derived from the resin composition. Since the resin layer after coating hardly undergoes a curing reaction, it has flexibility, but it is poor in flexibility as a sheet, and when the substrate is removed, the sheet is not self-supporting and difficult to handle. . However, since the B stage sheet is semi-cured, it is excellent in handleability.

The B stage sheet has a viscosity of the resin composition sheet of 10 ⁴ Pa · s to 10 ⁵ Pa · s at room temperature (25 ° C.), whereas 10 ² Pa · s to 10 ⁵ at 100 ° C. ^The viscosity decreases to ³ Pa · s. On the other hand, the cured resin layer, which will be described later, does not melt even by heating. The viscosity is measured by dynamic viscoelasticity measurement (frequency 1 Hz, load 40 g, temperature increase rate 3 ° C./min).

  The substrate is not particularly limited as long as it can withstand the temperature at the time of drying, and is preferably a release substrate that has been subjected to a release treatment so that it can be easily peeled off in a later step. As the release substrate, a metal foil such as a commonly used polyethylene terephthalate film with a release agent, a polyimide film, an aramid film, or an aluminum foil with a release agent can be used.

  The thickness of the resin composition sheet (B stage sheet) of the present invention can be appropriately selected according to the purpose. For example, the average thickness is preferably 30 μm to 300 μm, and the thermal conductivity, electrical insulation, and resin composition sheet. From the viewpoint of the flexibility of the (B stage sheet), it is preferably 8/7 times the maximum particle diameter of the inorganic filler and 60 μm to 200 μm. When the maximum particle diameter of the inorganic filler is 8/7 times or more and 60 μm or more, the electric insulation is excellent, and when it is 200 μm or less, the increase in thermal resistance is suppressed.

The resin composition sheet (B stage sheet) is obtained, for example, as follows.
First, the components described in the above resin composition are mixed, dissolved, and dispersed to prepare a resin composition. And the prepared resin composition is apply | coated on a mold release base material, and a coating film is formed. Application | coating can be implemented by a well-known method. Specific examples of the coating method include comma coating, die coating, lip coating, and gravure coating. Examples of a coating method for forming a resin composition sheet with a predetermined thickness include a comma coating method in which an object to be coated is passed between gaps, a die coating method in which a varnish-like resin composition having a flow rate adjusted from a nozzle is applied, and the like. Can be applied. Moreover, it can apply | coat, suppressing the isolation | separation by sedimentation of an inorganic filler by apply | coating while stirring gently the varnish reservoir part of each coating device as needed.

  The drying temperature of the coating film is desirably set as appropriate depending on the solvent used in the resin composition, and is generally about 80 ° C to 180 ° C. The drying time of the coating film can be determined by considering the gelation time and film thickness of the resin composition and the boiling point of the solvent used, and is not particularly limited. After the coating film is dried, the release substrate is removed to obtain a resin composition sheet (B stage sheet).

  The amount of volatile components in the resin composition sheet (B stage sheet) is preferably 1.2% by mass or less, and preferably 0.8% by mass or less, from the viewpoint of concern about bubble formation during outgas generation during curing. More preferably. Among the volatile components, the smaller the solvent component, the better. However, from the viewpoint of winding up of the obtained resin composition sheet (B stage sheet) to a roll or the like, it is preferably 0.4% by mass or more.

  The amount of volatile components in the resin composition sheet (B stage sheet) is measured as follows. The resin composition sheet (B stage sheet) obtained by the above method is cut into 50 mm squares, and obtained from the change in mass before and after drying when dried in a thermostatic bath preheated to 180 ° C. for 30 minutes.

  The resin composition sheet (B stage sheet) of the present invention is used after the surface is flattened in advance by hot pressing with a press or a roll laminator before being laminated or adhered to an adherend such as a metal substrate. May be. By flattening the surface, the resin that follows the shape of the adherend is in a state of oozing out on the surface, so that adhesion and insulation are improved. As a method of hot pressurization, a method such as a hot press, a hot roll, and a laminator can be arbitrarily selected. At this time, a resin composition sheet (B-stage sheet) may be obtained by applying a resin composition layer on a substrate and applying the substrate onto a dried resin composition layer and applying hot pressure. A resin composition sheet (B stage sheet) may be obtained by preparing two sheets obtained by applying a resin composition on a material and drying them, and bonding the resin composition layers so as to overlap each other. When two sheets are bonded together, it is preferable because pinholes during coating can be eliminated.

  When hot pressing is performed by hot pressing, it is preferable to perform by vacuum pressing in order to avoid air entrainment. The heating temperature is preferably set as appropriate according to the type of resin used in the resin composition, and is generally preferably 60 ° C to 180 ° C, more preferably 120 ° C to 150 ° C. Moreover, it is preferable that the vacuum degree which starts a pressurization shall be 3 kPa-0.1 kPa. The pressing pressure is preferably 0.2 MPa to 4 MPa, and more preferably 0.5 MPa to 2 MPa.

  The heating temperature of the laminator is preferably 70 ° C to 170 ° C, more preferably 80 ° C to 160 ° C, and still more preferably 90 ° C to 150 ° C. The pressure of the laminator is preferably 0.1 MPa to 3 MPa, more preferably 0.3 MPa to 2 MPa, and still more preferably 0.6 MPa to 1.5 MPa.

  The minimum melt viscosity of the resin composition sheet (B stage sheet) affects the fluidity of the resin composition in the pressure heating process from the B stage to the C stage. Therefore, adjusting the minimum melt viscosity in the temperature range of 20 ° C. to 200 ° C. applied in the pressure heating step is desirable from the viewpoint of handling and suppressing the outflow of the resin composition sheet (B stage sheet) from the end. .

The minimum melt viscosity of the resin composition sheet (B stage sheet) is a minimum value that appears due to a decrease in viscosity due to an increase in temperature and an increase in viscosity due to a curing reaction when the temperature dependence of shear viscoelasticity is measured.
Examples of conditions for measuring shear viscoelasticity include a heating rate of 5 ° C./min (press heating rate) and a frequency of 1 Hz to 10 Hz, and the measuring jig sandwiching the resin composition sheet (B stage sheet) is circular. A flat plate is mentioned. The sample may be a laminate of resin composition sheets (B stage sheets) as necessary.

  The minimum melt viscosity at 20 ° C. to 200 ° C. of the resin composition sheet (B stage sheet) is preferably 10 Pa · s to 1000 Pa · s, and from the viewpoint of the ability to follow unevenness of the adherend, 20 Pa · s to More preferably, it is 800 Pa · s, and more preferably 30 Pa · s to 600 Pa · s from the viewpoint of the margin of the pressure bonding condition. If the minimum melt viscosity is too low, the thickness of the heat conductive insulating layer will vary. If the minimum melt viscosity is too high, the heat conductive insulating layer will not adhere sufficiently to the adherend such as a copper foil or a metal substrate. A drop in force and a breakdown voltage occur. Therefore, when the minimum melt viscosity at 20 ° C. to 200 ° C. is in the above range, it exhibits excellent fluidity during heating and follows a substrate having a concavo-convex structure. Show.

  Further, the resin composition sheet (B stage sheet) of the present invention preferably has a flow rate of 130% or more and 210% or less, and more preferably 150% or more and 200% or less. This flow rate is an index of melt fluidity during thermocompression bonding. When the flow rate is 130% or more, the embeddability is sufficient.

The flow rate of the resin composition sheet (B stage sheet) is measured by the following method.
A resin composition sheet (B stage sheet) is stacked so that the total thickness becomes 180 μm to 200 μm, and a sample is prepared by punching out to 30 mm square. This sample is 0.5 mm thick Teflon (registered trademark) under atmospheric pressure conditions. ) The area change rate of the resin composition sheet (B stage sheet) before and after pressing is measured when pressed through a film at a temperature of 130 ° C. and a pressing pressure of 0.2 MPa for 20 seconds.
The area change rate is obtained from the change rate of the area (number of pixels) after taking a sample with a scanner of 300 DPI or more, binarizing with a sample analysis software (Adobe Photoshop).

  Flow rate (%) = (Area of resin composition sheet (B stage sheet) after pressing) / (Area of resin composition sheet (B stage sheet) before pressing)

<Resin composition sheet with metal foil>
The resin composition sheet with metal foil of the present invention has a metal foil and a resin composition layer formed from the resin composition provided on the metal foil. The resin composition layer is semi-cured and is preferably a so-called B stage.
The resin composition sheet with metal foil is produced by applying and drying the resin composition on the metal foil to form a resin composition layer, or by bonding the resin composition sheet to the metal foil. Can do. In addition, when a resin composition is applied and dried on a metal foil to form a resin composition layer, the resin composition layer is opposed to the resin composition layer as necessary after drying, as in the case of the resin composition sheet. As a result, the adhesive surface can be smoothed by back-to-back or by applying a release substrate to the resin composition layer and hot pressing, and this process can eliminate pinholes during coating. Is preferable because of the increase. Also, when the two resin composition layers are hot-pressed back to back so that the resin composition layers face each other, it is sufficient when the desired film thickness is too thick to be completely applied by one application. A film thickness can be obtained.

  As the metal foil, a metal foil made of any material of copper, aluminum, nickel, tin, or an alloy containing them can be used depending on the application. Further, the layer structure of the metal foil is not limited to one layer, and a composite foil of two to three layers can also be used. In view of low cost, high electrical conductivity, and convenience in circuit formation, copper foil is generally used. The copper foil may be an electrolytic copper foil or a rolled copper foil, but from the viewpoint of adhesiveness, an electrolytic copper foil is preferred unless the roughened surface roughness is not acceptable in terms of film thickness. Moreover, the thickness of copper foil can use the thing of suitable thickness by the electric current and electric power value to be used.

  The thickness of the metal foil is preferably 9 μm to 210 μm, more preferably 18 μm to 105 μm, and further preferably 35 μm to 70 μm. In the case of 9 μm or more, it is excellent in handling and can be prevented from being broken by a slight force. Moreover, when it is 210 micrometers or less, the usage-amount of expensive metal foil is suppressed.

  In order to improve the handleability of the metal foil, the metal foil may be handled with the carrier film attached. As such a carrier film, a slightly adhesive adhesive film, a self-adsorbing adhesive film, a UV curable adhesive film, or the like can be used. In the adhesion process by the resin composition sheet to the metal substrate and the metal foil, or in the coating process to obtain the resin composition sheet with the metal foil, the metal foil is folded by being in a state where the carrier film is adhered to the metal foil. Etc. can be suppressed.

  Other preferable production methods, thicknesses of the resin composition sheet, volatile content, minimum melt viscosity, flow rate, and the like are the same as those for the resin composition sheet.

<Thermal conductive insulating layer (C stage)>
The thermally conductive insulating layer is an adhesive layer that insulates between a metal substrate and a wiring layer or a metal foil in a metal base wiring board material or a metal base wiring board described later, and is a cured layer of the resin composition. . A B-stage sheet, which is a semi-cured product of the resin composition sheet, or a semi-cured resin composition sheet with a metal foil can be fully cured (C stage) to form a heat conductive insulating layer (C stage).

  More specifically, the metal substrate, the metal foil, and the metal foil are bonded to each other by pressurizing and heating a laminate in which the metal substrate, the resin composition sheet, and the metal foil are laminated in this order with a press machine or the like. This laminate may be obtained by laminating a metal substrate on a resin composition sheet with metal foil. When laminating a metal substrate on the resin composition sheet with metal foil, the metal plate is laminated on the opposite surface of the metal foil in the resin composition sheet with metal foil.

  The resin composition sheet or the metal foil-attached resin composition sheet in a semi-cured state (B stage) is re-melted in a pressure heating process, and the resin composition sheet adheres to the metal substrate and the metal foil. The composition sheet is fully cured (C stage) to become a heat conductive insulating layer (C stage), and the metal substrate and the metal foil are bonded. The thermally conductive insulating layer after the main curing is not melted by heating.

<Metal base wiring board material>
The metal base wiring board material includes a metal foil and a metal substrate, and includes a thermally conductive insulating layer that is a cured product of the resin composition between the metal foil and the metal substrate. The thermally conductive insulating layer may be a cured product of the resin composition sheet or a cured product of the resin composition sheet with metal foil. Hereinafter, the cured product of the resin composition sheet or the resin composition sheet with metal foil may be collectively referred to as “sheet cured product”. The metal substrate and the metal foil are insulated by the cured sheet in the present invention.

The metal substrate is made of a metal material having a high thermal conductivity and a large heat capacity, and examples thereof include copper, aluminum, iron, and alloys used for lead frames. The thicker the metal substrate, the higher the strength of the metal base wiring board. However, when the wiring board on which electronic components are mounted is integrated into a metal chassis or the like with screws or adhesive material, the metal board is used to improve the strength. Need not be particularly thick. The material of the metal substrate may be selected according to the purpose, such as aluminum when priority is given to weight reduction and workability, and iron when priority is given to strength.
In order to increase productivity, it is preferable to cut the wiring board into a size to be used after mounting the electronic component after the wiring board is manufactured in a large size. Therefore, it is desirable that the metal substrate has high workability for cutting.

  As a metal substrate of aluminum, aluminum or an alloy mainly composed of aluminum can be selected as a material, and various types are available depending on its chemical composition and heat treatment conditions, but it has high workability such as easy cutting, It is also preferable to select an aluminum alloy such as A5052 that is excellent in strength. Moreover, in order to improve the adhesive strength at the time of processing with resin, the surface is preferably roughened. Examples of the surface roughening method include methods such as buffing, jet scrub treatment, sand blast treatment, and alumite treatment. Jet scrub treatment is particularly preferred because it can be finished with little surface scratching and has low anisotropy.

  The wiring board material is produced by a method of sandwiching the resin composition sheet between a metal substrate and a metal foil and pressurizing and heating with a press machine or the like. Or it produces by the method etc. which pressurize and heat the resin composition sheet with metal foil, and a metal substrate. The conditions of the heating and pressure treatment for curing the resin composition sheet are appropriately selected according to the configuration of the resin composition sheet. For example, when the temperature is raised from room temperature, the heating temperature is preferably 80 ° C. to 250 ° C., the pressure is preferably 0.5 MPa to 8.0 MPa, the heating temperature is 130 ° C. to 230 ° C., and the pressure is 1.5 MPa to More preferably, it is 5.0 MPa.

  Further, when the curing reaction is insufficient after these pressure bonding steps, it can be post-cured in a thermostatic bath or the like. At that time, the film may be post-cured by being sandwiched between metal plates in order to suppress warpage, or may be post-cured by substituting with a nitrogen atmosphere or the like in order to suppress surface oxidation.

<Metal base wiring board>
The metal base wiring board includes a metal substrate and a wiring layer, and includes the cured sheet. The metal substrate and the wiring layer are insulated by the cured sheet.

  The wiring layer is obtained by wiring a metal foil of the metal base wiring board material. Etching is industrially preferable as a method for wiring the metal foil.

  The metal base wiring board preferably has a solder resist formed on the surface except for a pad portion for mounting electronic components. The metal base wiring board is preferably cut to the size of an electronic component mounting member such as an LED light source member after circuit processing and solder resist formation. For example, the electronic component is mounted by applying an electrical connection material such as solder to the pad portion of the metal base wiring board, placing the electronic component, and then passing through a solder reflow process.

<Power semiconductor device>
The power semiconductor device of the present invention includes the resin composition sheet, the resin composition sheet with metal foil, the B-stage sheet, the semi-cured resin composition sheet with metal foil, the metal base wiring board material, and the metal. It is produced using any one of the base wiring boards. 1 to 3 show configuration examples of the power semiconductor device of the present invention.

  FIG. 1 shows a copper plate 4 in which a power semiconductor chip 10 is disposed in a housing 14 via a solder layer 12, a cured product layer 2 of the resin composition of the present invention, and a water cooling jacket 20 via a grease layer 8. It is a schematic sectional drawing which shows the structural example of the power semiconductor device 100 comprised by laminating | stacking the thermal radiation base 6 arrange | positioned on the top. Since the heating element including the power semiconductor chip 10 is in contact with the heat dissipation base 6 through the cured product layer 2 of the resin composition of the present invention, heat dissipation is performed efficiently. In addition, the said thermal radiation base 6 can be comprised using copper and aluminum which have thermal conductivity.

FIG. 2 is a schematic cross-sectional view showing a configuration example of a power semiconductor device 150 configured by disposing the water cooling jacket 20 on both sides of the power semiconductor chip 10. In the power semiconductor device 150, the upper surface side of the power semiconductor chip 10 is connected to the water cooling jacket 20 via the two layers of copper plates 4. With such a configuration, generation of chip cracks and solder cracks can be more effectively suppressed.
In FIG. 2, the heat radiation base 6 and the water-cooled jacket 20 that are in close contact with the cured product layer 2 of the resin composition are disposed via the grease layer 8, but the cured product layer 2 of the resin composition and the water-cooled jacket 20 are disposed. And may be arranged so as to be in direct contact with each other.

FIG. 3 is a schematic cross-sectional view showing a configuration example of a power semiconductor device 200 configured by disposing the water cooling jacket 20 on both sides of the power semiconductor chip 10. In the power semiconductor device 200, both surface sides of the power semiconductor chip 10 are connected to the water cooling jacket 20 through one layer of copper plate 4.
In FIG. 3, the heat radiation base 6 and the water cooling jacket 20 that are in close contact with the cured product layer 2 of the resin composition are disposed via the grease layer 8, but the cured product layer 2 of the resin composition and the water cooling jacket 20 are directly connected. You may arrange | position so that it may contact.

<LED light source member>
The LED light source member of the present invention includes the resin composition sheet, the resin composition sheet with metal foil, the B stage sheet, the semi-cured resin composition sheet with metal foil, the metal base wiring board material, and the metal. It is produced using any one of the base wiring boards.
The LED light source member includes a cured product layer of a resin composition that is a heat conductive insulating layer between a metal substrate and a wiring layer, and an electronic component is mounted on the wiring layer. Using this LED light source device, an LED backlight unit or the like can be produced, or an LED electric light or an LED bulb can be produced.

FIG. 4 is a schematic cross-sectional view showing a configuration example of an LED light bar 300 as an example of the LED light source member of the present invention. The LED light bar 300 includes a housing 38, a grease layer 36, an aluminum substrate 34, a cured product layer 32 of the resin composition of the present invention, a circuit layer 42, and an LED chip 30 arranged in this order. The On the cured product layer 32 of the resin composition of the present invention, a fixing screw 40 for fixing an aluminum base substrate composed of the aluminum substrate 34, the cured product layer 32 of the resin composition, and the circuit layer 42 to the housing 38 is provided.
By disposing the LED chip 30 as a heating element on the aluminum substrate 34 via the cured product layer 32 of the resin composition of the present invention, heat can be efficiently radiated.

  FIG. 5 is a schematic cross-sectional view illustrating a configuration example of the light emitting unit 350 of the LED bulb. The light emitting part 350 of the LED bulb has a housing 38, a grease layer 36, an aluminum substrate 34, a cured product layer 32 of the resin composition of the present invention, a circuit layer 42, and an LED chip 30 arranged in this order. Composed.

  FIG. 6 is a schematic cross-sectional view showing an example of the overall configuration of the LED bulb 450. A power supply member 48 is disposed on the light emitting portion 350 of the LED bulb in FIG. 5 and the surface side of the housing 38 in the light emitting portion 350 where the LED chip 30 is not provided, and the electrode member 48 is sealed with a sealing resin 46. .

  FIG. 7 is a schematic cross-sectional view showing an example of the configuration of the LED substrate 400. The LED substrate 400 includes an aluminum substrate 34, a cured product 32 of the resin composition sheet of the present invention, a circuit layer 42, and an LED chip 30 arranged in this order. By disposing the LED chip 30 as a heating element on the aluminum substrate 34 via the circuit layer 42 and the cured product layer 32 of the resin composition of the present invention, heat can be efficiently radiated.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples. Unless otherwise specified, “part” and “%” are based on mass.

<Resin synthesis example 1>
Into a 3 L separable flask equipped with a stirrer, a cooler and a thermometer, 594 g of resorcinol, 66 g of catechol, 316.2 g of 37% formalin, 15 g of oxalic acid, and 100 g of water were added and heated to 100 ° C. while heating in an oil bath. The temperature rose. The reaction was continued for 4 hours at reflux temperature.
Thereafter, the temperature in the flask was raised to 170 ° C. while distilling off water. The reaction was continued for 8 hours while maintaining 170 ° C. Thereafter, concentration was performed under reduced pressure for 20 minutes to remove water and the like in the system, and a phenol resin having a structural unit represented by the general formula (I) was taken out. The number average molecular weight of the obtained phenol resin was 530, and the weight average molecular weight was 930. Moreover, the hydroxyl equivalent of the phenol resin was 65 g / eq. The obtained phenol resin contained a total of 35% of the monomers resorcinol and catechol.

<Inorganic filler mixture 1>
63 parts of alumina (Sumicorundum AA18, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 18 μm, and alumina (Sumicorundum AA3, manufactured by Sumitomo Chemical Co., Ltd., density 3) having a particle diameter D50 of 3 μm 0.95 g / ml) and 24.5 parts of alumina (Sumicorundum AA04, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 0.4 μm were mixed. As a result of measuring the oil absorption of the mixture, it was 6.2 ml / 100 g.

<Inorganic filler mixture 2>
66 parts of alumina (Sumicorundum AA18, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 18 μm, alumina (Sumicorundum AA3, manufactured by Sumitomo Chemical Co., Ltd., density 3) having a particle diameter D50 of 3 μm .98 g / ml) and 24 parts of alumina (Sumicorundum AA04, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 0.4 μm were mixed. As a result of measuring the oil absorption of the mixture, it was 6.7 ml / 100 g.

<Inorganic filler mixture 3>
74 parts of alumina (Sumicorundum AA18, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 18 μm, alumina (Sumicorundum AA3, manufactured by Sumitomo Chemical Co., Ltd., density 3) having a particle diameter D50 of 3 μm .98 g / ml) and 14 parts of alumina (Sumicorundum AA04, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 0.4 μm were mixed. As a result of measuring the oil absorption of the mixture, it was 7.6 ml / 100 g.

<Inorganic filler mixture 4>
63 parts of alumina (AL35-63, manufactured by Micron, density 3.80 g / ml) having a particle diameter D50 of 31 μm, alumina (AX3-32, manufactured by Micron, density of 3.77 g / ml) having a particle diameter D50 of 5 μm ) 17 parts of alumina (LS-235, manufactured by Nippon Light Metal Co., Ltd., density 3.94 g / ml) having a particle diameter D50 of 0.5 μm and spherical alumina (AO802, particle diameter D50 of 0.7 μm) 2 parts of Admatechs Co., Ltd., density 3.7 g / ml) were mixed. As a result of measuring the oil absorption of the mixture, it was 5.6 ml / 100 g.

<Inorganic filler mixture 5>
63 parts of alumina (AL35-63, manufactured by Micron, density 3.80 g / ml) having a particle diameter D50 of 31 μm, alumina (AX3-32, manufactured by Micron, density of 3.77 g / ml) having a particle diameter D50 of 5 μm ) 18 parts, 17 parts alumina (Sumicorundum AA04, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 0.4 μm, spherical alumina (AO802, 2 parts of Admatechs Co., Ltd., density 3.7 g / ml) were mixed. As a result of measuring the oil absorption of the mixture, it was 5.9 ml / 100 g.

<Inorganic filler mixture 6>
63 parts of alumina (A35-01, manufactured by Micron Corporation, density 3.77 g / ml) having a particle diameter D50 of 32 μm, alumina (AX3-32, manufactured by Micron Corporation, density 3.77 g / ml) having a particle diameter D50 of 5 μm ) 18 parts of alumina (LS-235, Nippon Light Metal Co., Ltd., density 3.94 g / ml) having a particle diameter D50 of 0.5 μm, 17 parts of spherical alumina (AO802, 2 parts of Admatechs Co., Ltd., density 3.7 g / ml) were mixed. As a result of measuring the oil absorption of the mixture, it was 5.6 ml / 100 g.

<Inorganic filler mixture 7>
63 parts of alumina (AX-116, manufactured by Micron, density 3.71 g / ml) having a particle diameter D50 of 19 μm, alumina (AX3-32, manufactured by Micron, density of 3.77 g / ml) having a particle diameter D50 of 5 μm ) 17 parts of alumina (LS-235, manufactured by Nippon Light Metal Co., Ltd., density 3.94 g / ml) having a particle diameter D50 of 0.5 μm and spherical alumina (AO802, particle diameter D50 of 0.7 μm) 2 parts of Admatechs Co., Ltd., density 3.7 g / ml) were mixed. As a result of measuring the oil absorption of the mixture, it was 7.0 ml / 100 g.

<Inorganic filler mixture 8>
63 parts of alumina (AS-30, Showa Denko KK, density 3.95 g / ml) having a particle diameter D50 of 18 μm, alumina (TA-982, Micron Corporation, density 3.67 g having a particle diameter D50 of 5 μm) 10.5 parts alumina (Sumicorundum AA04, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 0.4 μm and a particle diameter D50 of 0.7 μm 2 parts of spherical alumina (AO802, manufactured by Admatechs Co., Ltd., density 3.7 g / ml) was mixed. As a result of measuring the oil absorption of the mixture, it was 7.4 ml / 100 g.

<Inorganic filler mixture 9>
63 parts of alumina (AS-30, Showa Denko KK, density 3.95 g / ml) having a particle diameter D50 of 18 μm, alumina (TA-982, Micron Corporation, density 3.67 g having a particle diameter D50 of 5 μm) /2.5) 22.5 parts and 14.5 parts of alumina (Sumicorundum AA04, manufactured by Sumitomo Chemical Co., Ltd., density 3.98 g / ml) having a particle diameter D50 of 0.4 μm were mixed. As a result of measuring the oil absorption of the mixture, it was 8.1 ml / 100 g.

<Inorganic filler mixture 10>
62.5 parts of alumina having a particle diameter D50 of 22 μm (AS-20, Showa Denko KK, density 3.95 g / ml), alumina having a particle diameter D50 of 5 μm (LS-210, manufactured by Nippon Light Metal Co., Ltd.) 25 parts of density (3.94 g / ml) and 12.5 parts of alumina (LS-235, manufactured by Nippon Light Metal Co., Ltd., density 3.94 g / ml) having a particle diameter D50 of 0.5 μm were mixed. As a result of measuring the oil absorption of the mixture, it was 7.8 ml / 100 g.

[Example 1]
90.16 g of the inorganic filler mixture 1 was weighed in a 100 mL polypropylene container, 0.099 g of a silane coupling agent (Shin-Etsu Chemical Co., Ltd., KBM403), and 2-butanone (Wako Pure Chemical) as a solvent. 14.33 g (manufactured by Co., Ltd.), 0.181 g of a dispersant (manufactured by Enomoto Kasei Co., Ltd., ED-113) and 2.62 g (solid content) of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Further, 6.24 g of a bifunctional epoxy resin having a biphenyl skeleton (Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq) and naphthalene-based epoxy resin (DIC Corporation, HP4032D, epoxy equivalent 142 g / eq) of 0.004. 69 g and 0.100 g of an imidazole compound (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PZ-CN) were added. Furthermore, 120 g of an alumina ball having a diameter of 5 mm was added and stirred on a ball mill frame at 100 rpm for 12 hours, and then the alumina ball was filtered to obtain a varnish-like resin composition 1.

  The resin composition 1 obtained above is applied onto a PET film (Teijin DuPont Films, A53, thickness 50 μm) using an applicator having a gap of 75 μm and a table coater (manufactured by Tester Sangyo Co., Ltd.). Then, after air drying for 4 minutes, drying was performed at 120 ° C. for 4 minutes. The film thickness after drying was 50 μm. The two resin layers of the coated film after drying are overlapped, and then using a rubber roll laminator (VA-400III type, manufactured by Taisei Laminator Co., Ltd.), 100 ° C., linear pressure 14-30 N / m, 0.5 m / min. Bonding was carried out at a speed to obtain a sheet molded product (B stage sheet).

  The obtained sheet molding had a flow rate of 157% according to the aforementioned flow rate measurement method. Further, the obtained sheet molded product could be wound around a roll of a general coating machine in a state before bonding, and had a level of flexibility that did not cause cracking during winding and unwinding. Therefore, it can be applied with industrial large-scale equipment, and it can be said that it is excellent in productivity. Moreover, it had excellent flexibility even after bonding, and when the PET film was peeled off, it could be wound around a φ4 cm cylinder without breaking. In Table 2, those having this level of flexibility are indicated as “◯”.

  Moreover, a reverse phase liquid chromatograph analyzer (column: Inertsil ODS-34.6 mmφ × 250 mm manufactured by GL Sciences, detector: photodiode array (Hitachi L-7455), pump: Hitachi L-7100, analysis software: Hitachi D- 7000 Multi-System Manager) analyzed the components extracted with acetonitrile from the obtained sheet molded product at an absorbance of 278 nm. As a result, it was confirmed that about 8% of the monomer resorcinol remained.

<Preparation of hardened copper paste>
After the sheet molded product obtained above was cut into 200 mm squares, two resin composition sheets from which the PET on both sides were peeled were stacked, and the mat surfaces of two copper foils (manufactured by Nippon Electrolytic Co., Ltd., 35 μm) were each resin. The sheet was sandwiched so as to face the composition sheet. This is sandwiched between stainless steel plates with a thickness of 1 mm from both sides, and the pressure is reduced to a pressure of 10 kPa with a vacuum press (KVHC type manufactured by Kitagawa Seiki), and then the surface pressure is increased to 2 MPa. The temperature was raised, held for 1 hour, and cured in a press to obtain a cured copper paste.

<Production of aluminum base substrate>
The sheet molded product obtained above was cut into a 200 mm square, and then the resin composition sheet from which the PET on both sides had been peeled was sandwiched between a copper foil (35 μm) and an aluminum plate (A5052, thickness 1 mm). The copper foil was arranged so that the mat surface was in contact with the resin composition sheet. This is sandwiched between stainless steel plates with a thickness of 1 mm from both sides, and the pressure is reduced to a pressure of 10 kPa with a vacuum press (KVHC type manufactured by Kitagawa Seiki Co., Ltd.) with a surface pressure of 2 MPa, and from normal temperature to 170 ° C. at a heating rate of 5 ° C./min. The temperature was raised, held for 1 hour, and cured in a press to obtain an aluminum base substrate.

<Evaluation>
The characteristics were evaluated by the following method using the obtained cured copper paste and an aluminum base substrate. Table 1 shows the difference in composition between each Example and Comparative Example, and Table 2 shows the evaluation results of each Example and Comparative Example.

(Measurement of thermal conductivity)
The cured resin obtained by etching the copper foil of the cured copper foil was cut into a 10 mm square and blackened with a graphite spray, and then the thermal diffusivity was evaluated using a xenon flash method (NETZSCH LFA447 nanoflash). The thermal conductivity was obtained from the product of the density measured by the Archimedes method and the specific heat measured by DSC (DSC manufactured by Perkin Elmer, Pyris 1).

(Measurement of breakdown voltage)
A circular pattern with a diameter of 20 mm is formed on the copper foil surface of the aluminum base substrate by etching, and using YST-243-100RHO manufactured by YAMAYO TEST MACHINE, pressurizing speed 500 V / s, room temperature, Fluorinert (manufactured by Sumitomo 3M, FC-40) The average value was recorded at 20 or more measurement points.

(Measurement of peel strength)
In accordance with JIS-C6481 (1996 version), a 90 ° peel test piece was produced using the produced aluminum base substrate. Cut the metal substrate into 25 mm × 100 mm and leave the copper foil (35 μm) left at the center 10 mm width using a Tensilon tensile tester (Orientec TM-100) at a rate of 50 mm / min at 90 ° direction. The peel strength was measured from the average load at various times.

[Example 2]
A sheet molded product was produced in the same manner as in Example 1 except that the inorganic filler mixture 1 was changed to the inorganic filler mixture 2. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 115%.

[Comparative Example 1]
A sheet molded product was produced in the same manner as in Example 1 except that the inorganic filler mixture 1 was changed to the inorganic filler mixture 3. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 105%.

[Example 3]
90.16 g of the inorganic filler mixture 1 was weighed in a 100 mL polypropylene container, 0.099 g of a silane coupling agent (Shin-Etsu Chemical Co., Ltd., KBM403), and 2-butanone (Wako Pure Chemical) as a solvent. 14.33 g (manufactured by Co., Ltd.), 0.181 g of dispersant (manufactured by Enomoto Kasei Co., Ltd., ED-113) and 2.56 g (solid content) of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Further, bifunctional epoxy resin having biphenyl skeleton (Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq) 6.08 g, semi-hydrogenated biphenyl type epoxy resin (Mitsubishi Chemical Corporation YL6800, epoxy equivalent 193 g / eq) 0.92 g and 0.100 g of an imidazole compound (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PZ-CN). Furthermore, 120 g of an alumina ball having a diameter of 5 mm was added and stirred on a ball mill base at 100 rpm for 12 hours, and then the alumina ball was separated by filtration to obtain a varnish-like resin composition. Thereafter, a sheet molded product was produced in the same manner as in Example 1. The obtained sheet molded product was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 170%.

[Example 4]
A sheet molded product was prepared in the same manner as in Example 1 except that the inorganic filler mixture 1 was changed to the inorganic filler mixture 4 and the dispersant (ED-113, manufactured by Enomoto Kasei Co., Ltd.) was 0.36 g. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 220%.

[Example 5]
2-butanone (Wako Pure Chemical Industries, Ltd.) 13.6 g, phenol resin obtained in Resin Synthesis Example 1 2.49 g (solid content), bifunctional epoxy resin having a biphenyl skeleton (Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent of 175 g / eq) 5.92 g, naphthalene epoxy resin (manufactured by DIC Corporation, HP4032D, epoxy equivalent 142 g / eq) 0.66 g, imidazole compound (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PZ-CN) A sheet molded product was produced in the same manner as in Example 4 except that 0.095 g was used. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 180%.

[Example 6]
2-butanone (Wako Pure Chemical Industries, Ltd.) 13.7 g, phenolic resin obtained in Resin Synthesis Example 1 2.36 g (solid content), bifunctional epoxy resin having a biphenyl skeleton (Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq) 5.61 g, naphthalene epoxy resin (manufactured by DIC Corporation, HP4032D, epoxy equivalent 142 g / eq) 0.62 g, imidazole compound (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PZ-CN) A sheet molded product was produced in the same manner as in Example 4 except that 0.09 g was used. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 140%.

[Example 7]
90.16g of the inorganic filler mixture 4 was weighed in a polypropylene 100mL lidded container, 0.099g of silane coupling agent (Shin-Etsu Chemical Co., Ltd., KBM403), 2-butanone (Wako Pure Chemical) as a solvent. 13.59g manufactured by Co., Ltd., 0.361g dispersant (manufactured by Enomoto Kasei Co., Ltd., ED-113), 4.57g XLC-LL (Mitsui Chemicals, hydroxyl equivalent 174g / eq) as a phenol resin. Added and stirred. Furthermore, 4.02 g of a bifunctional epoxy resin having a biphenyl skeleton (Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq) and naphthalene-based epoxy resin (DIC Corporation, HP4032D, epoxy equivalent 142 g / eq) of 0.02 are used. 47 g and 0.095 g of an imidazole compound (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PZ-CN) were added. Furthermore, 120 g of an alumina ball having a diameter of 5 mm was added and stirred on a ball mill base at 100 rpm for 12 hours, and then the alumina ball was separated by filtration to obtain a varnish-like resin composition. Thereafter, a sheet molded product was produced in the same manner as in Example 1. The obtained sheet molded product was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 170%.

[Example 8]
90.16g of the inorganic filler mixture 4 was weighed in a polypropylene 100mL lidded container, 0.099g of silane coupling agent (Shin-Etsu Chemical Co., Ltd., KBM403), 2-butanone (Wako Pure Chemical) as a solvent. 15.40 g (manufactured by Co., Ltd.), 0.171 g of a dispersant (manufactured by Enomoto Kasei Co., Ltd., ED-113) and 2.46 g (solid content) of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Further, 5.86 g of a bifunctional epoxy resin having a biphenyl skeleton (manufactured by Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq.), Naphthalene-based epoxy resin (manufactured by DIC Corporation, HP4032D, epoxy equivalent 142 g / eq.). 0.65 g, 0.09 g of methyl methacrylate / butyl acrylate / ethyl acrylate / glycidyl methacrylate copolymer acrylic elastomer (manufactured by Nagase ChemteX Corporation, HTR860-P3- # 25) having a weight average molecular weight of 610,000. 0.095 g of an imidazole compound (manufactured by Shikoku Chemicals Co., Ltd., 2PZ-CN) was added. Furthermore, 120 g of an alumina ball having a diameter of 5 mm was added and stirred on a ball mill base at 100 rpm for 12 hours, and then the alumina ball was separated by filtration to obtain a varnish-like resin composition. Thereafter, a sheet molded product was produced in the same manner as in Example 1. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 151%.

[Comparative Example 2]
90.16g of the inorganic filler mixture 4 was weighed in a polypropylene 100mL lidded container, 0.099g of silane coupling agent (Shin-Etsu Chemical Co., Ltd., KBM403), 2-butanone (Wako Pure Chemical) as a solvent. 13.59g manufactured by Co., Ltd., 0.361g of dispersant (manufactured by Enomoto Kasei Co., Ltd., ED-113), 4.52g of XLC-LL (Mitsui Chemical Co., Ltd., hydroxyl equivalent 174g / eq) as a phenol resin. Added and stirred. Furthermore, 4.54 g of a bifunctional epoxy resin having a biphenyl skeleton (Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq) and 0.095 g of an imidazole compound (Shikoku Kasei Kogyo Co., Ltd., 2PZ-CN) were added. Furthermore, 120 g of an alumina ball having a diameter of 5 mm was added and stirred on a ball mill base at 100 rpm for 12 hours, and then the alumina ball was separated by filtration to obtain a varnish-like resin composition. Thereafter, a sheet molded product was produced in the same manner as in Example 1. The obtained sheet molding was brittle and easily cracked, and the flow rate by the above-described flow rate measurement method was 130%.

[Example 9]
A sheet molded product was produced in the same manner as in Example 4 except that the inorganic filler mixture 4 was changed to the inorganic filler mixture 7. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 165%.

[Example 10]
A sheet molded product was produced in the same manner as in Example 5 except that the inorganic filler mixture 4 was changed to the inorganic filler mixture 5. The obtained sheet molded product was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 170%.

[Example 11]
A sheet molded product was produced in the same manner as in Example 4 except that the inorganic filler mixture 4 was changed to the inorganic filler mixture 6. The obtained sheet molding was excellent in flexibility, and the flow rate according to the flow rate measurement method described above was 159%.

[Example 12]
90.16g of the inorganic filler mixture 4 was weighed in a polypropylene 100mL lidded container, 0.099g of silane coupling agent (Shin-Etsu Chemical Co., Ltd., KBM403), 2-butanone (Wako Pure Chemical) as a solvent. 14.33 g (manufactured by Co., Ltd.), 0.361 g of a dispersant (manufactured by Enomoto Kasei Co., Ltd., ED-113) and 2.47 g (solid content) of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Further, 5.87 g of a bifunctional epoxy resin having a biphenyl skeleton (manufactured by Mitsubishi Chemical Corporation, YL6121H, epoxy equivalent 175 g / eq), bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YDF-8170C, epoxy equivalent 160 g) / Eq) was added in an amount of 0.73 g, and imidazole compound (manufactured by Shikoku Chemicals Co., Ltd., 2PZ-CN) was added in an amount of 0.095 g. Furthermore, 120 g of an alumina ball having a diameter of 5 mm was added and stirred on a ball mill base at 100 rpm for 12 hours, and then the alumina ball was separated by filtration to obtain a varnish-like resin composition. Thereafter, a sheet molded product was produced in the same manner as in Example 1. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 185%.

[Example 13]
A sheet molded product was produced in the same manner as in Example 1 except that the inorganic filler mixture 1 was changed to the inorganic filler mixture 8. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 114%.

[Comparative Example 3]
A sheet molded product was produced in the same manner as in Example 1 except that the inorganic filler mixture 1 was changed to the inorganic filler mixture 9. The obtained sheet molding was excellent in flexibility, and the flow rate by the above-described flow rate measurement method was 102%, and almost no flow was observed.

[Comparative Example 4]
A sheet molded product was produced in the same manner as in Example 1 except that the inorganic filler mixture 1 was changed to the inorganic filler mixture 10. The obtained sheet molding was excellent in flexibility, and the flow rate by the above flow rate measurement method was 100%, and almost no flow was observed.

  From the above results, (A) an epoxy resin having a biphenyl skeleton, (B) an epoxy resin that is liquid at room temperature, (C) a phenol resin, and (D) an inorganic filler, the (D) inorganic filler It contains alumina, the content of the (D) inorganic filler is 75% by mass or more in the total solid content, and the oil absorption amount of the whole (D) inorganic filler contained is 7.5 ml / 100 g or less. In Examples 1 to 13, the flexibility when the B stage sheet is used, and the thermal conductivity, peel strength, and dielectric breakdown voltage when the C stage sheet is used are favorable, and (D) the oil absorption amount of the entire inorganic filler The smaller the value, the better the above characteristics.

Further, (B) all the examples and comparative examples containing the epoxy resin that is liquid at normal temperature, whereas (B) the comparative example 2 that does not contain the liquid epoxy resin at normal temperature did not provide flexibility. The flexibility was obtained.
In addition, from the comparison between Examples 1 and 3 and the comparison between Examples 4 and 12, if (B) an epoxy resin that is liquid at room temperature is added in a range that has a small effect on curability, the effect of the type can be seen. There wasn't.

  Further, in Comparative Examples 1, 3 and 4 where the oil absorption amount exceeds 7.5 ml / 100 g, sufficient adhesiveness was not obtained, whereas when the oil absorption amount was 7.5 ml / 100 g or less, it could be applied depending on the application. Adhesiveness was obtained, and sufficient adhesiveness was obtained in all examples in which the oil absorption was 6.5 ml / 100 g or less.

  Note that the smaller the oil absorption amount, the higher the maximum volume fraction of the inorganic filler calculated from the oil absorption amount. As the calculated maximum volume fraction increases, the amount of inorganic filler that can be filled increases, so increasing the filling amount tends to improve the thermal conductivity, and the same filling amount tends to have excellent peel strength and dielectric breakdown voltage. It was observed. Specifically, from the comparison of Examples 4, 5, and 6, when the filling amount of the inorganic filler was increased within the margin of the difference between the maximum volume fraction and the filling amount, the thermal conductivity increased. Along with this, the peel strength and dielectric breakdown voltage tend to decrease, but they can be designed according to the application and required characteristics. Further, from the comparison between Examples 5 and 8, it is possible to suppress the flow by adding a high molecular weight component such as an elastomer, and even when the fluidity becomes excessive, the fluidity can be controlled by adjusting the composition.

2 Hardened layer of resin composition 4 Copper plate 6 Heat dissipation base 8 Grease layer 10 Semiconductor chip 12 Solder layer 14 Housing 20 Water-cooled jacket 30 LED chip 32 Hardened layer of resin composition 34 Aluminum substrate 36 Grease layer 38 Housing (housing)
40 fixing screw 42 circuit layer 43 solder layer 46 sealing resin 48 power supply member 100 power semiconductor device 150 power semiconductor device 200 power semiconductor device 300 LED light bar 350 light emitting unit 400 LED substrate 450 LED bulb

Claims (14)

  (A) an epoxy resin having a biphenyl skeleton, (B) an epoxy resin that is liquid at room temperature, (C) a phenol resin, and (D) an inorganic filler, and (D) an alumina as the inorganic filler The resin composition in which the content of the (D) inorganic filler is 75% by mass or more in the total solid content, and the oil absorption amount of the whole (D) inorganic filler contained is 7.5 ml / 100 g or less. . The resin composition of Claim 1 containing the phenol resin which has a structural unit represented by the following general formula (I) as said (C) phenol resin.



[In General Formula (I), R ¹ represents an alkyl group, an aryl group, or an aralkyl group, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group, m represents an integer of 0 to 2, and n represents a number of 1 to 10. ] The inorganic filler (D) includes an inorganic filler group (D-1) having a particle diameter D50 corresponding to a cumulative 50% from the small particle size side of the weight cumulative particle size distribution of 5 μm to 100 μm, and D50 is the inorganic filler It is 1/2 or less of the filler group (D-1) and is 1 μm or more and 10 μm or less of the inorganic filler group (D-2), and D50 is 1/2 or less of the inorganic filler group (D-2). An inorganic filler group (D-3) of 0.1 μm or more and 5 μm or less,
The ratio of the inorganic filler group (D-1), (D-2) and (D-3) to the total amount of the (D) inorganic filler is 40% by mass to 90% by mass and 5% by mass, respectively. 40 mass% or less, 1 mass% or more and 30 mass% or less (however, the total mass% of the inorganic filler group (D-1), (D-2) and (D-3) is 100 mass%). The resin composition according to claim 1 or claim 2.   The inorganic filler (D-3) is 0.5 mass% to 15 mass% of spherical alumina having a particle diameter D50 corresponding to 50% accumulated from the small particle size side of the weight cumulative particle size distribution. The resin composition according to claim 3, which is contained in a range of not more than%.   The (B) normal temperature liquid epoxy resin includes a liquid epoxy resin having a skeleton derived from at least one selected from bisphenol A, bisphenol F, and dihydroxynaphthalene, and an equivalent ratio of total epoxy resin / total phenol resin The resin composition according to any one of claims 1 to 4, wherein is 0.8 to 1.1.   The resin composition sheet formed by shape | molding the resin composition as described in any one of Claims 1-5 in a sheet form. Metal foil,
A resin composition layer formed from the resin composition according to any one of claims 1 to 5 provided on the metal foil,
A resin composition sheet with a metal foil.   A B stage sheet, which is a semi-cured product of the resin composition sheet according to claim 6.   A semi-cured resin composition sheet with a metal foil, which is a semi-cured product of the resin composition sheet with a metal foil according to claim 7. Metal foil, metal plate,
A thermally conductive insulating layer that is a cured product of the resin composition according to any one of claims 1 to 5, provided between the metal foil and the metal plate,
Metal base wiring board material having Between the wiring layer, the metal plate, and the wiring layer and the metal plate, a thermally conductive insulating layer that is a cured product of the resin composition according to any one of claims 1 to 5,
Metal base wiring board having   The resin composition sheet according to claim 6, the resin composition sheet with metal foil according to claim 7, the B stage sheet according to claim 8, and the semi-cured resin composition with metal foil according to claim 9. The LED light source member manufactured using any one of a sheet | seat, the metal base wiring board material of Claim 10, and the metal base wiring board of Claim 11.   The resin composition sheet according to claim 6, the resin composition sheet with metal foil according to claim 7, the B stage sheet according to claim 8, and the semi-cured resin composition with metal foil according to claim 9. A power semiconductor device manufactured using any one of a sheet, a metal base wiring board material according to claim 10, and a metal base wiring board according to claim 11.   The resin composition according to any one of claims 1 to 5 containing (C) a phenol resin derived from dihydroxybenzene is applied onto a substrate, and the dihydroxybenzene remains in a monomer state in the sheet. The manufacturing method of the resin composition sheet | seat including the process shape | molded in a sheet form by making it dry on the conditions to do.