TW201333089A - Resin composition, resin sheet, prepreg, laminate, metal substrate, printed wiring board and power semiconductor device - Google Patents

Abstract

A resin composition including a first filler, which has a peak in a range of from 1 nm to less than 500 nm in a particle size distribution measured by a laser diffraction method and includes α -alumina; a second filler, which has a peak in a range of from 1 μ m to 100 μ m in a particle size distribution measured by a laser diffraction method; and a thermosetting resin having a mesogenic group in its molecule.

Description

Resin composition, resin sheet, prepreg, laminated board, metal substrate, printed wiring board, and power semiconductor device using the resin composition

The present invention relates to a resin composition, a resin sheet, a prepreg, a laminate, a metal substrate, a printed wiring board, and a power semiconductor device using the resin composition.

The electronic/electrical equipment from the motor and the generator to the printed wiring board and the IC (integrated circuit) wafer mostly includes a conductor for conducting electric power and an insulating material. In recent years, as heat dissipation has increased with the miniaturization of such devices, how to dissipate heat in an insulating material has become an important issue.

In the insulating material used for such machines, a cured resin composed of a resin composition is widely used from the viewpoints of insulation properties, heat resistance, and the like. However, since the thermal conductivity of the cured resin is generally low and it is an important cause of hindering heat dissipation, it is desired to develop a cured resin having high thermal conductivity.

As a means for achieving high thermal conductivity of the cured resin, there is a method in which a thermally conductive filler composed of a highly thermally conductive ceramic is filled in a resin composition to prepare a composite material. High thermal conductivity ceramics are known: boron nitride, Alumina, aluminum nitride, cerium oxide, cerium nitride, magnesium oxide, cerium carbide, and the like. By filling a resin composition with a thermally conductive filler in which high thermal conductivity and electrical insulating properties are combined, high thermal conductivity and insulation are coexisted in the composite material.

In the above-mentioned report, Japanese Laid-Open Patent Publication No. 2009-13227 discloses a technique of adding a small amount of an inorganic filler having a nanoparticle size in addition to the above-mentioned thermally conductive filler having a fine particle size, thereby obtaining good electrical insulating properties and thermal conductivity. A resin composition for an electrical insulating material.

In addition, as a method for achieving high thermal conductivity of a resin cured product, a method of sequentially arranging monomers having a liquid crystal group in the molecule in order to increase the thermal conductivity of the resin itself has been studied. As an example of such a monomer, an epoxy resin monomer disclosed in Japanese Patent No. 4118691 is proposed.

Here, as one aspect of the insulating material disposed in the electric device, there is a method in which a resin substrate such as a woven fabric or a non-woven fabric is used to impregnate the resin composition for the purpose of improving dimensional stability and mechanical strength. A prepreg is prepared on the fibrous substrate. The method of impregnating a resin composition into a fibrous substrate is a vertical coating method in which a fibrous substrate is immersed in a resin composition, and a fibrous substrate is coated on the supporting film. A horizontal coating method that is pressed to impregnate it. When a resin composition containing a filler such as the above is used, a horizontal coating method is often applied in consideration of filler deposition, and the horizontal coating method is less likely to cause variations in composition in the fiber substrate.

Resin composition of the above thermally conductive filler to be filled with a particle size In order to achieve the high thermal conductivity required in recent years, it is necessary to increase the filling amount of the filler. The resin composition is highly filled with a filler, and the viscosity is remarkably increased by the interaction of the surface of the filler with the resin, and it is sometimes easy to entrap air and trap bubbles. Further, since the frequency at which the fillers are fitted to each other increases, the fluidity sometimes decreases remarkably. As a result, the resin composition highly filled with the filler is not easy to eliminate the voids generated by the surface structure of the adhesive material not well embedded, and the bubbles generated during the coating, thereby producing the resin composition. The insulating material tends to be easily broken by the voids/bubbles.

Further, when the resin composition is impregnated into the fiber base material to prepare a prepreg, if the amount of the filler in the resin composition is large, the filler may be entangled with the fibers, and the resin may not be from the fiber substrate. The surface is sufficiently oozing or the gap between the fibers is not sufficiently filled, and voids remain. Further, when the resin does not sufficiently bleed out from the surface of the fibrous base material, the adhesion of the prepreg to the adherend material may be insufficient to cause peeling of the interface. Moreover, the voids in the interface/fiber substrate of the adherent material sometimes cause a decrease in insulation.

Here, in order to improve the fluidity of the resin composition to be filled with the filler, there are generally the following methods: (1) a method of lowering the viscosity of the resin; and (2) reducing the filler by surface treatment of the filler or addition of a dispersant. A method of the amount of resin bound by the surface.

However, if the viscosity of the resin is simply lowered, the exudation of the resin itself from the surface of the fiber substrate can be improved, but the case where the filler is fitted to the fiber cannot be improved. Therefore, there is a problem that the filler remains on the fiber and only the resin oozes from the surface of the fiber substrate, and if the pressure is too large, only the resin Exudation forms defects such as voids. Further, there is a problem in that the viscosity of the resin composition is excessively lowered, and filler deposition occurs in the thickness direction of the coating film of the resin composition, and the density distribution of the filler occurs in the thickness direction of the coating film.

On the other hand, when the fluidity of the resin composition is increased by merely subjecting the filler to surface treatment or adding a dispersing agent, there is a problem in that the surface treatment is increased in such a manner that the resin sufficiently bleeds from the surface of the fibrous substrate. The filler coverage or the amount of the dispersant added hinders the chemical bonding of the filler to the resin, and the thermal conductivity as a composite material is lowered.

In addition, when monomers having a liquid crystal group in the molecule are arranged in order to achieve high thermal conductivity of the resin composition, since the monomer having a liquid crystal group is generally crystallized and is solid at normal temperature, it may be more general. The resin used is more difficult to handle. Further, if the filler is highly filled, the above-described difficulty is increased, so that it may be more difficult to form.

As a method for solving the above-mentioned problem, for example, a method of adding a small amount of an inorganic filler having a nanoparticle size is mentioned. However, the conditions disclosed in Japanese Laid-Open Patent Publication No. 2009-13227 result in an increase in dielectric breakdown property but heat conduction. The rate is lower than that of the resin composition to which no inorganic filler is added.

Under such circumstances, the problem to be solved by the present invention is to provide a resin composition capable of coexisting excellent thermal conductivity and excellent fluidity. Further, the problem to be solved by the present invention is to provide a resin sheet, a prepreg, a laminate, a metal substrate, a printed wiring board, and a power semiconductor device which are formed using the resin composition and have excellent thermal conductivity. And excellent insulation.

The inventors of the present invention have made efforts to carry out research in order to solve the above problems, and have completed the present invention as a result. In other words, the present invention encompasses the following aspects.

<1> A resin composition comprising: a first filler having a peak in a range of 1 nm or more and less than 500 nm in a particle size distribution measured by a laser diffraction method, and containing α - Alumina; a second filler having a peak in a particle size distribution measured by a laser diffraction method in a range of 1 μm to 100 μm; and a thermosetting resin having a liquid crystal group in a molecule.

<2> A resin composition comprising: a first filler having an average particle diameter (D50) corresponding to a cumulative 50% of a cumulative particle size distribution from a small particle diameter side of 1 nm or more and less than 500 nm, And containing α-alumina; the second filler having an average particle diameter (D50) corresponding to a cumulative 50% of the weight cumulative particle size distribution from the small particle diameter side is 1 μm to 100 μm; and a thermosetting resin. There is a liquid crystal group in the molecule.

The resin composition according to the above <1>, wherein the content of the first filler is from 0.1% by volume to 10% by volume based on the total volume.

The resin composition according to any one of the above aspects, wherein the second filler contains a nitride filler.

The resin composition according to the above <4>, wherein the nitride filler contains at least one selected from the group consisting of boron nitride and aluminum nitride.

The resin composition according to any one of the above aspects, wherein the content of the second filler is 55 to 85% by volume in the total volume.

The resin composition as described in any one of <1> to <6>, The thermosetting resin is an epoxy resin.

The resin composition according to any one of the above aspects, wherein the liquid crystal group has a structure in which three or more six-membered ring groups are connected in a straight chain.

The resin composition according to the above <7>, wherein the epoxy resin is as shown in the following formula (III) or (IV):

[In the general formula (III), Ar ¹ , Ar ² and Ar ³ are the same or different and each represents a divalent group represented by any one of the following formulas; R ¹ , R ² , R ³ , R ⁴ and R ^{5 ;} And R ⁶ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms; and Q ¹ and Q ² are the same or different, each represents a linear alkyl group having 1 to 9 carbon atoms, and constitutes the linear chain. The methylene group of the alkyl group may be substituted by an alkylene group having 1 to 18 carbon atoms, and -O- or -N(R ⁷ )- may be inserted between the methylene groups; here, R ⁷ Represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms]

[wherein R represents independently a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, a represents an integer of 1 to 8, b, e and g represent an integer of 1 to 6, and c represents an integer of 1 to 7, d And h represents an integer of 1 to 4, and f represents an integer of 1 to 5. Further, when R is a plural number in the above divalent group, all Rs may represent the same group, and may represent different groups.

In the formula (IV), R ¹ to R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

The resin composition as described in any one of the above-mentioned <1> which further contains the phenol type novolak resin.

The resin composition according to the above <10>, wherein the phenol novolak resin contains a group selected from the group consisting of the following general formulae (I-1) and (I-2). Compound of at least one of the structural units shown:

In the general formulae (I-1) and (I-2), R ¹ each independently 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 each independently represents an integer of 0 to 2, and n each independently represents an integer of 1 to 7.

<12> The resin composition according to the above <10> or <11>, wherein The phenolic novolak resin is contained in an amount of from 5 to 80% by mass based on the monomer composed of the phenolic compound constituting the phenol novolak resin.

<13> A semi-hardened resin composition according to any one of the above <1> to <12>.

<14> A hardened resin composition, which is a hardened body of the resin composition according to any one of <1> to <12>.

<15> A sheet-like molded article of the resin composition according to any one of <1> to <12> above.

<16> The resin sheet according to the above <15>, wherein the flow amount in the semi-hardened state is 130% to 210%.

<17> A prepreg comprising a fiber base material, wherein the resin composition is impregnated into the fiber base material, and the resin composition according to any one of <1> to <12>.

<18> A laminated board having an adhesive material, a semi-hardened resin composition layer or a cured resin composition layer, wherein the semi-hardened resin composition layer or the cured resin composition layer is disposed on the adherend material, The semi-hardened resin composition layer is the resin composition according to any one of the above <1> to <12>, wherein the resin sheet according to <15> or <16>, and the above <17> The at least one semi-hardened body selected from the group consisting of the prepreg, the hardened resin composition layer, the resin composition according to any one of the above <1> to <12>, the aforementioned < A cured sheet of at least one selected from the group consisting of the resin sheet according to <16> and the prepreg according to <17>.

<19> A metal substrate in which layers are laminated: metal foil, hardened The resin composition layer, and the resin sheet according to any one of the above <1> to <12>, wherein the resin composition according to any one of the above <1> to <12>, or the resin sheet according to <15> or <16>, And at least one hardened body selected from the prepreg according to the above <17>.

<20> A printed wiring board in which the metal plate, the hardened resin composition layer, and the wiring layer are laminated, and the hardened resin composition layer is any one of the above <1> to <12>. The resin composition, the resin sheet according to the above <15> or <16>, and the at least one selected from the prepreg according to <17>.

<21> A power semiconductor device comprising: a semiconductor module in which a metal plate, a solder layer, and a semiconductor wafer are sequentially laminated; a heat dissipating member; and the hardened body of the resin sheet according to <15> or <16>, It is disposed between the metal plate of the semiconductor module and the heat dissipation member.

According to the present invention, it is possible to provide a resin composition capable of coexisting excellent thermal conductivity and excellent fluidity. Further, it is possible to provide a resin sheet, a prepreg, a laminate, a metal substrate, and a printed wiring board, which are formed using the resin composition, and have excellent thermal conductivity and excellent insulating properties.

10‧‧‧Second filler

20‧‧‧First filler

30‧‧‧A cured product composed of a thermosetting resin having a liquid crystal group

30a‧‧‧High-order structure forming part

40‧‧‧The average particle size (D50) other than α-alumina is more than 1 nm and less than 500 nm

50‧‧‧A cured product composed of a thermosetting resin having no liquid crystal group

102‧‧‧hardened body of resin sheet

104‧‧‧heating base substrate

106‧‧‧Metal plates

108‧‧‧Semiconductor wafer

110‧‧‧ solder layer

112‧‧‧Molded resin

114‧‧‧ Sealing material

Fig. 1 is a schematic cross-sectional view showing an example of a configuration of a cured resin composition of the present embodiment.

Fig. 2 is a view for explaining the constitution of the cured resin composition of the present embodiment. A schematic diagram of an example.

Fig. 3 is a schematic view for explaining an example of the configuration of the cured resin composition of the embodiment.

Fig. 4 is a schematic view showing an example of a configuration of a cured resin composition different from the present embodiment.

Fig. 5 is a schematic view showing an example of a configuration of a cured resin composition different from the present embodiment.

Fig. 6 is a schematic cross-sectional view conceptually showing an example of a configuration of a cured resin composition of Comparative Example 1.

Fig. 7 is a schematic cross-sectional view showing an example of a configuration of a cured resin composition of Comparative Examples 2 and 4 conceptually.

Fig. 8 is a schematic cross-sectional view conceptually showing an example of a configuration of a cured resin composition of Comparative Example 5.

Fig. 9 is a general view showing a particle size distribution when the particle diameter is set to the horizontal axis and the frequency is set to the vertical axis, which is measured by the laser diffraction method. Further, in the present specification, the peak is a distribution. The maximum value refers to the part indicated in the figure.

Fig. 10 is a general view showing the particle size distribution when the particle diameter is set to the horizontal axis and the weight is cumulatively set to the vertical axis, which is measured by the laser diffraction method; further, in the present specification, the average particle diameter (D50) means the part indicated in the figure.

Fig. 11 is a schematic cross-sectional view showing an example of a configuration of a power semiconductor device according to the embodiment.

Fig. 12 is a schematic cross-sectional view showing an example of a configuration of a power semiconductor device according to the embodiment.

[Preferred form of implementing the invention]

In this specification, the word "step" is not intended to be an independent step. When it cannot be clearly distinguished from other steps, it is included in the term as long as the intended purpose of the step can be achieved. In addition, in this specification, the numerical range represented by "~" is shown by the range of the numerical value after the "~", and the minimum value and the maximum value respectively. In addition, in the present specification, when a plurality of (two or more) substances corresponding to the respective components are present in the composition, the amount of each component in the composition means that it is present in the composition unless otherwise specified. The total amount of the plurality of substances in the middle.

<Resin composition>

The resin composition of the present invention comprises: a first filler having a peak in a range of 1 nm or more and less than 500 nm in a particle size distribution measured by a laser diffraction method, and containing α-alumina The second filler having a peak in a particle size distribution measured by a laser diffraction method in a range of 1 μm to 100 μm, and a thermosetting resin having a liquid crystal group in the molecule. The resin composition can be produced in the following manner, for example, by mixing a first filler having an average particle diameter (D50) corresponding to a cumulative 50% of the weight cumulative particle size distribution from the small particle diameter side of 1 nm or more. And less than 500 nm, and containing α-alumina; the second filler, which has an average particle diameter (D50) corresponding to a cumulative 50% of the weight cumulative particle size distribution from the small particle diameter side, is 1 μm to 100 μm; A thermosetting resin having a liquid crystal group in its molecule.

Alternatively, the resin composition of the present invention comprises: a first filler which is flat corresponding to a cumulative 50% of the weight cumulative particle size distribution from the small particle diameter side The average particle diameter (D50) is 1 nm or more and less than 500 nm, and contains α-alumina; the second filler, which has an average particle diameter corresponding to a cumulative 50% of the weight cumulative particle size distribution from the small particle diameter side ( D50) is 1 μm to 100 μm; and a thermosetting resin having a liquid crystal group in its molecule.

The composition of the resin composition can further include other components as needed. With such a configuration, excellent thermal conductivity and excellent fluidity can be coexisted.

When the thermosetting resin having a liquid crystal group in the molecule is used in combination with the first filler having a specific average particle diameter of α-alumina, the thermal conductivity of the cured resin composition can be rapidly increased. A thermosetting resin having a liquid crystal group in the molecule, and the fact that the cured product is excellent in thermal conductivity is described in Japanese Patent No. 4118691. However, when the thermosetting resin is used in combination with an α-alumina filler having a specific average particle diameter, the thermal conductivity of the cured resin composition is improved, and the degree of improvement cannot be described in Japanese Patent No. 4118691. To predict. The reason for this is, for example, a high-order structure of a thermosetting resin having a high order of formation on the surface of a nanoparticle, that is, an α-alumina filler.

Further, in the present invention, since the average particle diameter of the first filler is smaller than the average particle diameter of the second filler, the thermal conductivity of the cured resin composition is greatly improved. Specifically, a second filler having an average particle diameter (D50) of 1 μm to 100 μm is combined with a first filler containing an α-alumina having an average particle diameter (D50) of 1 nm or more and less than 500 nm. The thermal conductivity of the cured resin composition can be greatly improved. In view of this, the inventors' opinions are as follows, for example. However, the present invention is not limited to the following estimation mechanism.

Usually, in the cured resin composition composed of a filler and a resin, a resin exists at the interface between the fillers. Since the thermal conductivity of the resin is lower than that of the filler, heat is not easily transferred between the fillers. Therefore, no matter how highly filled the filler is to keep the fillers tight, there is still a large loss of heat conduction at the filler interface. On the other hand, the cured resin composition of the present invention efficiently transfers heat due to the thermosetting resin existing between the fillers and having a liquid crystal group in the molecule, and thermosetting the first filler and the liquid crystal group in the molecule. The resin combination can further improve the thermal conductivity between the first filler and the first filler and the second filler, so that the heat transfer loss at the filler interface is less, and as a result, the thermal conductivity of the cured resin composition should be improved.

This speculation mechanism will be further explained while referring to the drawings.

Fig. 1 is a cross-sectional view conceptually showing the cured resin composition of the present embodiment. The arrow in Fig. 1 is a schematic representation of the heat conduction path. As shown in Fig. 1, since the first filler 20 has a smaller average particle diameter than the second filler 10, it can enter the gap formed by the second fillers 10 in the cured resin composition. Further, on the surface of the first filler 20, the cured product 30 composed of a thermosetting resin having a liquid crystal group forms a high-order structure as shown in an enlarged view of Fig. 1. Therefore, the first filler 20 having the higher-order structure of the resin cured product 30 formed on the surface constitutes a new heat conduction path connecting the second fillers 10 to each other. As a result, a higher thermal conductivity should be obtained due to an increase in the effective heat conduction path in the hardened resin composition.

Further, from the second drawing and the third drawing, the reason why the cured resin composition of the present embodiment can obtain a high thermal conductivity can be described in more detail.

As shown schematically in Figure 2, on the surface of the first filler 20, The cured product 30 composed of a thermosetting resin having a liquid crystal group forms a high-order structure. Therefore, around the first filler 20, there is a high-order structure forming portion (labeled as 30a) capable of efficiently transferring heat. Since the first filler 20 having this high-order structure forming portion 30a is gathered, it is possible to remove the region where heat conduction is lost. Therefore, heat should be transferred very efficiently between the fillers.

As shown schematically in Fig. 3, the first filler 20 having the higher-order structure forming portion 30a is filled in such a manner as to fill the gap formed by the second fillers 10, which is very advantageous for the reasons described above. Transfer heat efficiently, and should be able to achieve higher thermal conductivity. Similarly to Fig. 1, the arrows in Fig. 3 schematically show the heat conduction paths. The heat can be transferred without loss of heat conduction in the following order, for example, the second filler 10, the high-order structure forming portion (30a) formed of the cured product 30, the first filler 20, and the high-order formed by the cured product 30. The structure forms a portion 30a and a second filler 10.

On the other hand, in Figs. 4 and 5, an example of the configuration of the cured resin composition different from the present embodiment is shown.

Fig. 4 is a view schematically showing a case where the hardened resin composition does not contain the first filler 20. At this time, since the gap formed by the second fillers 10 with each other hinders heat conduction, a high thermal conductivity should not be obtained.

Fig. 5 is a view schematically showing that the hardened resin composition contains a filler which is not equivalent to the first filler 20 (for example, an average particle diameter (D50) composed of a substance other than α-alumina is 1 nm or more and less than 500 nm. In the case of filler 40). At this time, even if the cured product 30 composed of a thermosetting resin having a liquid crystal group is used, a high-order structure of the cured product 30 is not formed on the surface of the filler 40. Therefore, the fillers 40 are formed between each other and between the second filler 20 and the filler 40. The gap can block heat conduction. Therefore, a higher thermal conductivity should not be obtained.

In addition, FIG. 6 is a cross-sectional view conceptually showing the cured resin composition of Comparative Example 1 to be described later. Similarly to the first embodiment, the arrows in FIG. 6 schematically show heat conduction paths. Fig. 6 is a view showing a cured resin composition comprising: a second filler 10; and a cured product 30 composed of a thermosetting resin having a liquid crystal group, which is hardened as shown in Fig. 6. The resin composition fills the gap formed by the second fillers 10 with the resin cured product 30 in which the higher-order structure has been formed. The resin cured product 30 having a higher-order structure has a higher thermal conductivity than the general cured resin, but the thermal conductivity is higher than that of the resin having the liquid crystal-based resin cured material 30 in the surface of FIG. 20 lower. Therefore, the cured resin composition as shown in Fig. 6 should have a lower thermal conductivity than the cured resin composition as shown in Fig. 1.

On the other hand, Fig. 7 is a cross-sectional view conceptually showing the cured resin compositions of Comparative Examples 2 and 4 to be described later. Similarly to Fig. 1, the arrows in Fig. 7 schematically show heat conduction paths. Figure 7 is a view showing a hardened resin composition which is composed of a filler 40 having an average particle diameter (D50) other than α-alumina of 1 nm or more and less than 500 nm (e.g., yttrium oxide filler or γ). - Alumina filler); second filler 10; and cured product 30 composed of a thermosetting resin having a liquid crystal group, such as the hardened resin composition shown in Fig. 7, which is averaged other than α-alumina The particle diameter (D50) is a filler 40 of 1 nm or more and less than 500 nm and a resin cured product 30 having a high-order structure formed to fill a gap formed by the second fillers 10 with each other. The average particle diameter (D50) other than α-alumina is a filler 40 of 1 nm or more and less than 500 nm, and a cured resin 30 having a high-order structure, and the thermal conductivity is formed more than the surface in FIG. The first filler 20 having a higher-order structure of the liquid crystal-based resin cured product 30 is lower. Therefore, the cured resin composition as shown in Fig. 7 should have a lower thermal conductivity than the cured resin composition as shown in Fig. 1.

In addition, Fig. 8 is a cross-sectional view conceptually showing the cured resin composition of Comparative Example 5 to be described later. Similarly to Fig. 1, the arrows in Fig. 8 schematically show heat conduction paths. Figure 8 is a view showing a cured resin composition which is composed of a first filler 20, a second filler 10, and a cured product 50 composed of a thermosetting resin having no liquid crystal group, like the eighth As shown in the figure, the hardened resin composition fills the gap formed by the second fillers 10 with the first filler 20 and the resin cured product 50 which does not form a high-order structure. The first filler 20 and the resin cured product 50 which does not form a high-order structure have lower thermal conductivity than the first filler 20 having a higher-order structure in which the liquid crystal-based resin cured product 30 is formed on the surface in Fig. 1 . Therefore, the cured resin composition as shown in Fig. 8 should have a lower thermal conductivity than the cured resin composition as shown in Fig. 1.

Here, the high-order structure means a structure including a high-order structure in which the constituent elements are arranged to form a minute ordered structure, and corresponds to, for example, a crystal phase and a liquid crystal phase. The presence of such a high-order structure can be easily determined by observation by a polarizing microscope. In other words, when observed in a crossed Nicol state, it can be discriminated by observing interference fringes due to depolarization.

This high-order structure is usually present in the hardened resin composition in an island shape, and a domain structure is formed, and each of the islands corresponds to one higher-order structure. The constituent elements of this higher-order structure itself, generally It is formed by covalent bonds.

Further, the present inventors have found that a thermosetting resin having a liquid crystal group in a molecule is used as a thermosetting resin, that is, a high-order structure of a resin cured product having a high order of formation is formed on the surface of the first filler. Further, the present inventors have found that a thermosetting resin having a liquid crystal group exhibits higher order with the first filler as a core, and the thermal conductivity of the cured resin itself is also improved. In the hardened resin composition of the present invention, the first filler having a high-order structure in which a resin-hardened material having a liquid crystal group is formed on the surface thereof enters the gap between the first fillers, and the heat conduction path is increased, so that a higher thermal conductivity can be obtained. .

Further, the high-order structure of the cured resin body exists on the surface of the first filler, and can be found in the following manner.

When a polarizing microscope (for example, BX51 manufactured by OLYMPUS Co., Ltd.) is used to observe a cured product (thickness: 0.1 μm to 20 μm) of a thermosetting resin having a liquid crystal group of 5 volume% to 10% by volume of the first filler, Interference fringes were observed centering on the filler, and interference fringes were not observed in the region where no filler was present. From this, it is understood that the cured resin having a liquid crystal group has a high-order structure centering on the filler. Further, the observation is not performed in the orthogonal polarization state, but must be performed in a state where the analyzer is rotated by 60° with respect to the polarizer. In the case of the orthogonal polarization state, the region where the interference fringes are not observed (that is, the region where the resin does not form the high-order structure) becomes a dark field and cannot be distinguished from the filler portion. However, the analyzer is rotated by 60° with respect to the polarizer, and the region where the interference fringes are not observed does not become a dark field: it can be distinguished from the filler portion.

Furthermore, it is not limited to the first filler, as long as it is boron nitride, aluminum oxide, and nitride. The high thermal conductivity ceramic filler such as aluminum or cerium oxide can observe the above phenomenon, but when it is α-alumina, even if the average particle diameter (D50) is outside the range of the first filler, the interference is formed centering on the filler. The area of the stripes will still be great.

The resin composition described above in combination includes a first filler and a second filler having a specific average particle diameter (D50). The average particle diameter (D50) in the present invention means a particle diameter which is accumulated up to 50% when the weight cumulative particle size distribution from the small particle diameter side is plotted.

Here, the weight cumulative particle size distribution is measured by a laser diffraction method. The particle size distribution measurement by the laser diffraction method can be performed using a laser diffraction scattering particle size distribution measuring apparatus (for example, LS13 manufactured by BECKMAN COULTER Co., Ltd.). The preparation of the filler dispersion for measurement is carried out by diluting the filler into a specific amount of light in the same organic solvent when the filler is a dispersion of an organic solvent, and the amount of light is an appropriate amount of light in sensitivity of the device. Further, when the filler is a powder, the powder is placed in a 0.1% by mass aqueous solution of sodium metaphosphate and dispersed by ultrasonic waves, and measured in a concentration of a specific amount of light, which is the sensitivity in the apparatus. On the appropriate amount of light.

As a result of the above measurement, the first filler has a peak in the particle size distribution in the range of 1 nm or more and less than 500 nm, and the second filler has a particle size distribution in the range of 1 μm to 100 μm. A peak can be observed inside.

By making the resin composition include the first filler having an average particle diameter (D50) of 1 nm or more and less than 500 nm, it is of course possible to obtain an average particle diameter (D50) of 1 μm to 100 μm in the resin composition. The second filler is lubricated with each other, and the lubricating effect between the second filler and the fibrous substrate can also be obtained in the prepreg, the prepreg is such that the resin composition is impregnated into the fibrous substrate Made.

The resin sheet and the resin-attached metal foil formed by using such a resin composition having excellent fluidity can well fill the pores formed during the production and the pores between the interface and the material to be adhered. Improve insulation breakdown. Further, the prepreg formed by impregnating the resin composition with the fiber base material can smoothly slide the second filler without being fitted into each other in the gap of the fiber base material, and the resin composition can be derived from the resin base. The material is exuded well, and the pores between the inside of the substrate and the interface of the adhered material can be well filled at the time of pasting, thereby improving the insulation breakdown property. Further, due to good fluidity, if hot pressing is applied after coating, the resin can be bleed out to the surface of the fiber base material, and the adhesiveness is also improved.

Since the resin composition is excellent in thermal conductivity and fluidity, it has a laminated board, a metal substrate, and a printed wiring board which are an insulating layer which hardens this resin composition, and can exhibit higher thermal conductivity and insulation.

Hereinafter, the physical properties of the material used in the resin composition and the resin composition will be described.

(first filler)

The foregoing resin composition includes a first filler having a peak in a range of 1 nm or more and less than 500 nm in a particle size distribution measured by a laser diffraction method, and containing α-alumina . In other words, the foregoing resin composition includes: a first filler having an average particle diameter (D50) corresponding to a cumulative 50% of the weight cumulative particle size distribution from the small particle diameter side of 1 nm or more and less than 500 nm, and containing α - Alumina.

From the viewpoint of improving thermal conductivity and fluidity, the aforementioned first filling In the particle size distribution measured by the laser diffraction method, the peak is preferably in the range of 1 nm to 450 nm, and the peak is preferably in the range of 50 nm to 450 nm. The peak is preferably in the range of 100 nm to 450 nm, and has a peak in the range of 100 nm to 300 nm, and has a peak in the range of 100 nm to 200 nm.

Alternatively, from the viewpoint of improving thermal conductivity and fluidity, the average particle diameter (D50) of the first filler is preferably 1 nm to 450 nm, preferably 50 nm to 450 nm, and 100 nm to 450 nm. More preferably, it is preferably 100 nm to 300 nm, and preferably 100 nm to 200 nm.

If the average particle diameter (D50) of the first filler is 500 nm or more, the first filler may not sufficiently enter the gap between the second fillers, and as a result, the filling amount of the filler in the resin composition as a whole may be lowered, and the thermal conductivity may be lowered. The tendency. Further, when the average particle diameter (D50) of the first filler is less than 1 nm, sufficient lubricity between the second fillers or between the second filler and the fibrous base material may not be obtained.

The manner in which the average particle diameter of the first filler is determined is as described above.

The aforementioned first filler contains α-alumina. It contains α-alumina and has a tendency to obtain sufficient thermal conductivity. Further, when α-alumina is contained, a resin composition having a high melting point, high mechanical strength, and electrical insulating properties can be obtained, and the filling property of the first filler can be improved.

From the viewpoint of thermal conductivity and filling properties, the shape of the α-alumina is preferably spherical. The shape of the α-alumina can be measured by a scanning electron microscope (SEM).

The first filler may further contain alumina other than α-alumina. When it further contains alumina other than α-alumina, oxidation other than α-alumina The aluminum particles are preferably spherical. The shape of the filler can be measured in the same manner as the shape of the above α-alumina. Examples of the alumina other than the α-alumina include γ-alumina, θ-alumina, and δ-alumina.

The first filler may further contain a ceramic other than alumina as needed. It may contain, for example, boron nitride, aluminum nitride, cerium oxide, magnesium oxide, cerium nitride, cerium carbide or the like.

The content of α-alumina in the first filler is preferably 80% by volume or more based on the total volume of the first filler, more preferably 90% by volume or more, and preferably 100%, from the viewpoint of thermal conductivity and fluidity. More volume %. When α-alumina is used, the thermosetting resin having a liquid crystal group in the molecule has a high-order structure forming ability and a tendency to obtain sufficient thermal conductivity.

Further, the presence of α-alumina in the first filler can be confirmed by an X-ray diffraction spectrum. Specifically, the presence of α-alumina can be confirmed by using the peak unique to α-alumina as an index, as described in the specification of Japanese Patent No. 3759208.

The content of the first filler contained in the resin composition is not particularly limited. The first filler preferably contains from 0.1% by volume to 10% by volume based on the total volume of the total solid content of the resin composition. If the resin composition contains 0.1% by volume to 10% by volume of the first filler in the total volume, the following effects can be obtained: further improving the lubricity between the second fillers and between the second filler and the fibrous substrate Moreover, the thermal conductivity of the resin composition is further increased.

The content of the first filler is preferably from 0.2% by volume to 10% by volume, and preferably from 0.2% by volume to 8% by volume, from the viewpoint of improving thermal conductivity and fluidity.

Here, the total solid content of the resin composition means the remainder obtained by removing the volatile component from the resin composition.

In the present specification, the content (% by volume) of the first filler is a value obtained by the following formula.

Content of first filler (% by volume) = (Aw / Ad) / ((Aw / Ad) + (Bw / Bd) + (Cw / Cd) + (Dw / Dd) + (Ew / Ed)) × 100

Here, each variable is as follows.

Aw: mass composition ratio of the first filler (% by mass)

Bw: mass composition ratio of the second filler (% by mass)

Cw: mass composition ratio (% by mass) of thermosetting resin

Dw: mass composition ratio of hardener (% by mass)

Ew: mass composition ratio (% by mass) of other optional components (excluding organic solvents)

Ad: the specific gravity of the first filler

Bd: the specific gravity of the second filler

Cd: the proportion of thermosetting resin

Dd: the proportion of hardener

Ed: The proportion of other optional ingredients (excluding organic solvents)

The first filler may be used singly or in combination of two or more. For example, two or more kinds of α-alumina having different D50s in an average particle diameter (D50) of 1 nm or more and less than 500 nm can be used in combination, but the combination is not limited thereto.

When the particle size distribution curve is drawn by setting the particle diameter to the horizontal axis and the frequency to the vertical axis, the first filler may have a single peak or a plurality of peaks. Using a particle size distribution curve having a plurality of peaks of the first filler, Further, the filling property between the second fillers can be further improved, and the thermal conductivity as a composition of the cured resin can be improved. The first filler having a plurality of peaks in the particle size distribution curve can be composed of the following fillers, for example, two or more kinds of first fillers having different average particle diameters (D50).

Regarding the combination of the first fillers, for example, when two kinds of aluminas having different average particle diameters (D50) are combined, for example, a mixed filler obtained by mixing the filler (a) and the filler (b) may be mentioned. The average particle diameter (D50) of the filler (a) is 250 nm or more and less than 500 nm, and the average particle diameter (D50) of the filler (b) is 1/2 or less of the filler (a) and is 1 nm or more. It is less than 250 nm, and is preferably 90% by volume to 99% by volume of the filler (a) and 1% by volume to 10% by volume of the filler (b) with respect to the total volume of the first filler. (a) is filled with a ratio of the total volume % of (b) to 100% by volume.

(second filler)

The resin composition contains at least one second filler having a peak in a range of from 1 μm to 100 μm in a particle size distribution measured by a laser diffraction method. In other words, the resin composition contains at least one second filler, and the average particle diameter (D50) determined from the weight cumulative particle size distribution is from 1 μm to 100 μm.

The second filler is not particularly limited as long as it has a higher thermal conductivity than the cured resin of the thermosetting resin and the average particle diameter (D50) is from 1 μm to 100 μm, and can be used from the viewpoint of generally improving thermal conductivity. It is suitably selected as a filler among the fillers. Furthermore, the second filler is preferably electrically insulating.

The thermal conductivity of the second filler is not particularly limited as long as it is higher than the cured resin. For example, it is better to have a thermal conductivity of 1 W/mK or more, and 10 W/mK or higher is preferred.

Specific examples of the second filler include boron nitride, aluminum nitride, aluminum oxide, cerium oxide, magnesium oxide, and the like. From the viewpoint of further improving the thermal conductivity, a nitride filler is preferred, and at least one of boron nitride and aluminum nitride is preferred.

The second filler may be used singly or in combination of two or more. For example, boron nitride and aluminum nitride can be used in combination, but are not limited to this combination.

The content of the second filler is not particularly limited, and it is preferably 55 to 85% by volume based on the total volume of the total solid content of the resin composition. When the content of the second filler in the resin composition is 55 vol% or more, the thermal conductivity is more excellent. Moreover, when it is 85 volume% or less, moldability and adhesiveness will be improved. The content of the second filler in the present invention is preferably from 60% by volume to 85% by volume in the total volume of the total solid content of the resin composition from the viewpoint of improving the thermal conductivity, from the viewpoint of fluidity. More preferably, it is 65 to 85% by volume.

In the present specification, the content (% by volume) of the second filler is a value obtained by the following formula.

Content of second filler (% by volume) = (Bw / Bd) / ((Aw / Ad) + (Bw / Bd) + (Cw / Cd) + (Dw / Dd) + (Ew / Ed)) × 100

Here, each variable is as follows.

Aw: mass composition ratio of the first filler (% by mass)

Bw: mass composition ratio of the second filler (% by mass)

Cw: mass composition ratio (% by mass) of thermosetting resin

Dw: mass composition fee of hardener (% by mass)

Ew: mass composition ratio (% by mass) of other optional components (excluding organic solvents)

Ad: the specific gravity of the first filler

Bd: the specific gravity of the second filler

Cd: the proportion of thermosetting resin

Dd: the proportion of hardener

Ed: The proportion of other optional ingredients (excluding organic solvents)

When the particle size distribution curve is plotted by setting the particle diameter to the horizontal axis and the frequency to the vertical axis, the second filler may have a single peak or a plurality of peaks. By using the second filler having a plurality of peaks in the particle size distribution curve, the filling property between the second fillers can be further improved, and the thermal conductivity as the cured resin composition can be improved.

When the second filler has a plurality of peaks when the particle size distribution curve is drawn, it is preferable to have a peak in the range of 1 μm to 80 μm, and preferably have a peak in the range of 1 μm to 50 μm to be 1 μm. The peak value is better in the range of ~30 μm, and the peak is excellent in the range of 1 μm to 20 μm. In other words, from the viewpoint of thermal conductivity, the average particle diameter (D50) of the second filler is preferably 1 μm to 80 μm, preferably 1 μm to 50 μm, more preferably 1 μm to 30 μm, and 1 is used. Very good μm~20 μm. Further, the particle size distribution curve has a second filler having a plurality of peaks, and can be composed of the following fillers, for example, two or more kinds of second fillers having different average particle diameters (D50).

With regard to the combination of the foregoing second fillers, for example, when two types of filler groups having different average particle diameters (D50) are combined, it is preferable to mix, for example, a filler (A) and a filler (B). Mixed filler, average particle of the filler (A) The diameter (D50) is 10 μm or more and 100 μm or less, and the average particle diameter (D50) of the filler (B) is 1/2 or less of the filler (A) and is 1 μm or more and less than 10 μm, and is relative to the foregoing The total volume of the second filler is 60% by volume to 90% by volume of the filler (A), and 10% by volume to 40% by volume of the filler (B) (however, the total volume % of the fillers (A) and (B) is Filled in proportion to 100% by volume).

Further, when three types of fillers having different average particle diameters are combined, it is preferable to use, for example, a mixed filler obtained by mixing a filler (A'), a filler (B') and a filler (C'). The average particle diameter (D50) of the filler (A') is 10 μm or more and 100 μm or less, and the average particle diameter (D50) of the filler (B') is 1/2 or less and 5 μm or more of the filler (A'). And less than 10 μm, the average particle diameter (D50) of the filler (C') is 1/2 or less of the filler (B') and is 1 μm or more and less than 5 μm, and is relative to the total of the foregoing second filler. The volume is 30% by volume to 89% by volume of the filler (A'), 10% by volume to 40% by volume of the filler (B'), and 1% by volume to 30% by volume of the filler (C') (only, filler ( A'), a total volume % of (B') and (C') is 100% by volume) to be filled.

When the resin composition is applied to a resin sheet or a laminate to be described later, the average particle diameter (D50) of the fillers (A) and (A') is a resin resin sheet or a cured resin composition layer in the laminate. It is preferable to appropriately select the film thickness, and when the resin composition is applied to the prepreg described later, the average particle diameter (D50) of the fillers (A) and (A') is the prepreg corresponding to the target. The film thickness and the thickness of the pores of the fiber base material are preferably selected as appropriate.

When there is no other particular limitation, the average particle diameter of the aforementioned fillers (A) and (A') is preferably as large as possible from the viewpoint of thermal conductivity. On the other hand, from the viewpoint of thermal resistance, the aforementioned film thickness is as close as possible within the range of ensuring the required insulation. It is better to make it thinner. Therefore, the average particle diameter of the fillers (A) and (A') is preferably 10 μm to 100 μm, and is preferably 10 μm to 80 μm from the viewpoint of filler filling property, thermal resistance, and thermal conductivity. It is preferably 10 μm to 50 μm, preferably 1 μm to 30 μm, and most preferably 1 μm to 20 μm.

The fillers (A) and (A') are preferably boron nitride or aluminum nitride, but the fillers (B) and (B') and the filler (C') are not necessarily required to be boron nitride or aluminum nitride. It can be, for example, alumina.

As described above, when the filler groups having different average particle diameters (D50) are combined to constitute the second filler, the average particle diameter (D50) in the entire second filler is from 1 μm to 100 μm.

Further, the resin composition may further contain a third filler as needed, and the average particle diameter (D50) of the third filler is deviated from 1 nm or more and less than 500 nm and 1 μm to 100 μm and has thermal conductivity. Even if a third filler having an average particle diameter (D50) of more than 1 nm and less than 500 nm and 1 μm to 100 μm is used in combination, the average filler (D50) is a second filler of 1 μm to 100 μm, and is still contained. It is preferably 55 to 85% by volume in the total volume of the resin composition.

The average particle diameter (D50) of the third filler is preferably 500 nm or more and less than 1 μm, and more preferably 500 nm or more and 800 nm or less. Further, when the foregoing resin composition contains the third filler, the content ratio of the third filler is not particularly limited. For example, it is preferably from 1% by volume to 40% by volume based on the total volume of the resin composition, and preferably from 1% by volume to 20% by volume.

Furthermore, the preferred aspect of the thermal conductivity of the third filler is the same as that of the second filler described above.

The ratio of the average particle diameter (D50) of the second filler contained in the resin composition to the average particle diameter (D50) of the first filler (second filler/first filler) is not particularly limited. From the viewpoint of thermal conductivity and fluidity, it is preferably from 10 to 500, more preferably from 30 to 300. Further, when the particle size distribution curve of the second filler has a plurality of peaks, the ratio of the particle diameter corresponding to the peak of the largest particle diameter to the average particle diameter (D50) of the first filler is preferably 10 to 500. It is preferably 30 to 300, and more preferably 100 to 300.

The ratio of the content (vol%) of the second filler contained in the resin composition to the content (volume%) of the first filler (second filler/first filler) is not particularly limited. From the viewpoint of thermal conductivity and fluidity, it is preferably 5 to 500, and preferably 5 to 350.

(thermosetting resin)

The resin composition contains at least one kind of thermosetting resin, and the thermosetting resin has a liquid crystal group in the molecule.

Here, the liquid crystal group means a functional group which readily exhibits crystallinity or liquid crystallinity by the action of intermolecular interaction. Specific examples thereof include a biphenyl group, a phenyl benzoate group, an azophenyl group, a distyryl group, and the like.

The thermosetting resin in the present invention is not particularly limited as long as it is a compound having at least one liquid crystal group and at least two thermosetting functional groups in the molecule. Specifically, for example, an epoxy resin, a polyimide resin, a polyamidimide resin, and the like (triazine) resin, phenol resin, melamine resin, polyester resin, cyanate resin, and modified resin of these resins. These resins may be used alone or in combination of two or more.

From the viewpoint of heat resistance, the above thermosetting resin is derived from epoxy resin, phenol resin and three At least one resin selected from the resins is preferred, and from the viewpoint of adhesion, an epoxy resin is preferred. These epoxy resins may be used alone or in combination of two or more.

The specific content of the epoxy resin having a liquid crystal group in the molecule (hereinafter also referred to as "liquid crystal-containing epoxy resin") can be referred to, for example, in Japanese Patent No. 4118691.

In the semi-hardened body and the hardened body of the resin composition, whether the resin has the anisotropic structure described in Japanese Patent No. 4118691, and X-rays can be performed on the semi-hardened resin composition and the cured resin composition. Diffraction (for example, an X-ray analysis device manufactured by Rigaku Co., Ltd.) is judged. When CuK _α 1 ray is used to measure in a range of a tube voltage of 40 kV, a tube current of 20 mA, and 2θ=2° to 30°, the resin has a semi-hardened resin composition and a cured resin composition. The anisotropic structure described in the specification of Patent No. 4118691 can exhibit a diffraction peak in a range of 2θ=2° to 10°. Further, since the diffraction peak of the thermally conductive filler composed of the highly thermally conductive ceramic can be expressed in the range of 2θ=20° or more, it can be clearly distinguished from the peak of the resin.

Specific examples of the liquid crystal-containing epoxy resin are listed below, but the thermosetting resin in the present invention is not limited thereto.

The liquid crystal-containing epoxy resin may, for example, be an epoxy resin represented by the following formula (II) (described in Japanese Patent No. 4118691) or an epoxy resin represented by the following formula (III) (Japan) Epoxy resin represented by the following general formula (IV), which is described in JP-A-200819759, JP-A-2008-13759 An epoxy resin represented by the following general formula (V) (described in JP-A-2010-241797) and the following general formula (VI) are shown in JP-A-2011-74366. Epoxy resin (described in Japanese Laid-Open Patent Publication No. 2011-98952) and the like.

In the formula (II), n is 4, 6, or 8.

In the formula (III), Ar ¹ , Ar ² and Ar ³ are the same or different and each represents a divalent group represented by any one of the following formulas; R ¹ , R ² , R ³ , R ⁴ and R ⁵ and R ^{6 is the} same or different and represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms; and Q ¹ and Q ² are the same or different, each represents a linear alkyl group having 1 to 9 carbon atoms, and constitutes the linear chain. The alkylene group of the alkylene group may be substituted by an alkylene group having 1 to 18 carbon atoms, and -O- or -N(R ⁷ )- may be inserted between the methylene groups; here, R ⁷ represents A hydrogen atom or an alkyl group having 1 to 18 carbon atoms.

Here, R independently represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, a represents an integer of 1 to 8, b, e and g represent an integer of 1 to 6, and c represents an integer of 1 to 7, d and h represents an integer of 1 to 4, and f represents an integer of 1 to 5. Further, when R is a plural number in the above divalent group, all Rs may represent the same group, and may represent different groups.

In the formula (IV), R ¹ to R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

In the formula (V), R ¹ each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R ² independently represents a hydrogen atom and a carbon number of 1 to 3; An alkyl group or an alkoxy group having 1 to 3 carbon atoms, and R ³ each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R ⁴ each independently represents a hydrogen atom; An alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms; and R ⁵ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms; and R ⁶ is a hydrogen atom; An alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms; R ⁷ represents a hydrogen atom, a methyl group or an alkoxy group having 1 to 3 carbon atoms; and R ⁸ represents a hydrogen atom, a methyl group or a carbon number of 1 ~3 alkoxy group.

Further, as a commercially available product, for example, YL6121H (manufactured by Mitsubishi Chemical Corporation) can be mentioned.

The liquid crystal-containing epoxy resin is preferably an epoxy resin having a structure in which three or more six-membered ring groups are connected in a linear form in a liquid crystal group. Such a resin easily forms a high-order structure and can attain a higher thermal conductivity. The number of the 6-membered ring groups to be linearly connected in the liquid crystal group is preferably three or more, and from the viewpoint of moldability, three or four are preferable.

The 6-membered ring group which is linearly connected in the liquid crystal group may be a 6-membered ring group derived from an aromatic ring or a 6-membered ring group derived from an aliphatic ring, and the representative of the aromatic ring is Benzene, pyridine, toluene or acene such as naphthalene, and the aliphatic ring is cyclohexane, cyclohexene, piperidine or the like. its Among them, at least one of the 6-membered ring groups derived from the aromatic ring is preferred, and one of the 6-membered ring groups which are linearly linked in the liquid crystal group is an aliphatic ring and the remaining rings are An aromatic ring is preferred.

In the liquid crystal-containing epoxy resin, an epoxy resin having a structure in which three or more 6-membered rings are connected in a linear form in the liquid crystal group corresponds to the above formulas (II) to (VI). Among them, from the viewpoint of thermal conductivity, an epoxy resin represented by the formula (III) or the formula (VI) is preferred. In addition, since the epoxy resin represented by the following formulas (VII), (VIII), (IX), and (X) is excellent in fluidity and adhesion in addition to thermal conductivity, it can be preferably applied to the above resin. Composition.

(1-(3-Methyl-4-epoxyethylmethoxyphenyl)-4-(4-epoxyethylmethoxyphenyl)-1-] described in Japanese Patent No. 4619770 Cyclohexene

(1-(3-Methyl-4-epoxyethylmethoxyphenyl)-4-(4-epoxyethylmethoxyphenyl)benzene) described in Japanese Patent No. 4619770.

(4-(2,3-epoxypropoxy)phenyl}cyclohexyl 4-(2,3-epoxypropoxy)benzoate described in JP-A-2011-74366 ).

(4-(2,3-epoxypropoxy)-3-methyl)benzoic acid 4-{4-(2,3-epoxypropoxy) described in JP-A-2011-74366 Phenyl}cyclohexyl ester).

Further, the thermosetting resin may be in the form of a monomer or a prepolymer obtained by reacting a part of a monomer with a curing agent or the like. A resin having a liquid crystal group in the molecule is generally easy to be crystallized and has a low solubility in a solvent. However, since a part of the resin is reacted and polymerized, crystallization can be suppressed, so that the moldability may be improved.

The thermosetting resin is preferably from 10% by volume to 40% by volume based on the total volume of the total solid content of the resin composition, from the viewpoint of moldability, adhesiveness, and thermal conductivity, and contains 15% by volume. More preferably, 35 vol% is more preferably 15 vol% to 30 vol%.

In addition, when the resin composition contains a curing agent or a curing accelerator to be described later, the content of the thermosetting resin referred to herein includes such hardening. The content of the agent and the hardening accelerator.

The ratio (volume%) of the thermosetting resin contained in the resin composition to the content (volume%) of the first filler (thermosturable resin/first filler) is not particularly limited. From the viewpoint of thermal conductivity and fluidity, it is preferably from 1 to 200, more preferably from 2.5 to 150.

In the above epoxy resin, the epoxy resin monomer represented by the formula (III) or the formula (IV) is formed to have a higher order centering on the α-alumina contained in the first filler. The tendency of higher-order structures of sex. As a result, there is a tendency that the thermal conductivity after hardening is rapidly increased. The reason for this is that α-alumina is present, that is, the aforementioned epoxy resin having formed a high-order structure becomes an efficient heat conduction path, and high thermal conductivity can be obtained.

In addition, when the D50 of the α-alumina contained in the resin composition is 1 nm or more and less than 500 nm, the formation of the high-order structure of the epoxy resin monomer tends to be more remarkable, and the thermal conductivity is also Will be more significantly improved.

The epoxy resin monomer represented by the formula (III) or the formula (IV) is converted into a temperature of the liquid crystal phase, that is, a melting temperature of up to 150 °C. Therefore, if the epoxy resin monomer is to be melted, it may be different depending on the curing agent and the curing catalyst to be used, but the curing reaction is often carried out simultaneously with the melting. As a result, the epoxy resin monomer becomes a hardened body before the high-order structure is formed. However, in a system containing α-alumina having a D50 of 1 nm or more and less than 500 nm, it is possible to obtain a hardened body in which the above-mentioned epoxy resin monomer has formed a high-order structure even when heated at a high temperature.

The reason for this is that the high-order structure of the above epoxy resin monomer is obtained by using the aforementioned α-alumina having a D50 of 1 nm or more and less than 500 nm. The effect is more significant. In other words, the reason is that a high-order structure is formed rapidly before the hardening reaction of the epoxy resin monomer is performed, that is, the α-alumina having a D50 of 1 nm or more and less than 500 nm is rapidly formed.

Further, when the epoxy resin monomer represented by the general formula (III) or the general formula (IV) is used alone, only a nematic structure can be exhibited. Therefore, in the epoxy resin monomer having a liquid crystal group in the molecular structure, it is difficult to form a high-order structure. However, by combining the epoxy resin monomer with a filler containing α-alumina to form a composite material, the epoxy resin monomer represented by the general formula (III) or the general formula (IV) exhibits a smectic type ( Smectic) structure, the layered structure has a higher order than the nematic structure. As a result, high thermal conductivity is exhibited, and the degree cannot be predicted from a hardened body composed of a resin monomer.

Further, the nematic structure and the smectic structure are each one of liquid crystal structures. A nematic structure in which the long axis of the molecule faces the same direction and is a liquid crystal structure having only a direct order. In contrast, the smectic structure has a one-dimensional positional order in addition to the orientation order, and is a liquid crystal structure having a layer structure. The order of the smectic structure is higher than that of the nematic structure. Therefore, when the cured resin body exhibits a layered structure, the thermal conductivity is also high.

By using a polarizing microscope as described above, it is observed that the epoxy resin monomer represented by the general formula (III) or the general formula (IV) contains 5 to 10% by volume of α-alumina having a different D50. For the cured product of the composition, when the α-alumina having a D50 of 1 nm or more and less than 500 nm is used, the area of the region where the interference fringes are displayed is the largest. From this, it can be judged that when α-alumina having a D50 of 1 nm or more and less than 500 nm is used, the high-order structure formation effect of the epoxy resin monomer represented by the general formula (III) or the general formula (IV) is very high. Significant.

In the formula (III), Ar ¹ , Ar ² and Ar ^{3 are} preferably the same or different and are a divalent group (1), (3) or (8) represented by the following formula, and are preferably Ar ¹ Ar ³ is (8) and Ar ² is (3) is preferred. R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are preferably the same or different and are preferably a hydrogen atom or a methyl group, and a hydrogen atom is preferred. Q ¹ and Q ² are preferably a linear alkyl group which is the same or different and is a carbon number of 1 to 4, and preferably a methylene group.

In the formula (IV), R ¹ to R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.

Further, 2 to 4 of R ¹ to R ⁴ are preferably a hydrogen atom, and 3 or 4 are preferably a hydrogen atom, and 4 or more are preferably a hydrogen atom. When any of R ¹ to R ⁴ is an alkyl group having 1 to 3 carbon atoms, it is preferred that at least one of R ¹ and R ⁴ is an alkyl group having 1 to 3 carbon atoms.

(hardener)

The resin composition preferably contains at least one type of curing agent. The curing agent is not particularly limited as long as it can thermally harden the thermosetting resin. When the thermosetting resin is an epoxy resin, the curing agent may, for example, be an acid anhydride-based curing agent, an amine-based curing agent, a phenol-based curing agent, or a thiol-based curing agent; and an imidazole-like curing agent; Medium hardener, etc.

In the heat resistance, it is preferred to use at least one selected from the group consisting of an amine curing agent and a phenol curing agent, and at least one phenol system is used from the viewpoint of storage stability. A hardener is preferred.

As the amine-based curing agent, a compound which is generally used can be used without particular limitation, and it can be a commercially available product. Among them, a polyfunctional hardener having two or more functional groups is preferred from the viewpoint of curability, and a polyfunctional hardener having a strong skeleton is preferred from the viewpoint of thermal conductivity.

Examples of the bifunctional amine-based curing agent include 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, and 4,4'-diaminodiphenyl. 4,4'-diaminodiphenyl sulfone, 4,4'-diamino-3,3'-dimethoxybiphenyl, 4,4'-diaminophenyl benzoate, 1,5 - Diaminonaphthalene, 1,3-diaminonaphthalene, 1,4-diaminonaphthalene, 1,8-diaminonaphthalene, and the like.

Among them, from the viewpoint of thermal conductivity, at least one selected from 4,4'-diaminodiphenylmethane and 1,5-diaminonaphthalene is preferred, and 1,5-diamine is used. The naphthalene is preferred.

As the phenolic curing agent, a compound which is generally used can be used without particular limitation, and a commercially available low molecular phenolic compound and a phenol resin which is subjected to novolak can be used.

As the low molecular phenolic compound, for example, a monofunctional phenolic compound such as phenol, o-cresol, m-cresol or p-cresol; a bifunctional phenolic compound such as catechol, resorcin or hydroquinone can be used. And a trifunctional phenolic compound such as 1,2,3-trihydroxybenzene, 1,2,4-trihydroxybenzene or 1,3,5-trihydroxybenzene. In addition, a phenol novolak resin which is obtained by linking these low molecular phenolic compounds to a novolak by a methylene chain or the like can also be used as a curing agent.

From the viewpoint of thermal conductivity, the phenolic curing agent is preferably a bifunctional phenolic compound such as catechol, resorcin or hydroquinone; or a methylene chain A phenolic novolak resin obtained by combining these compounds, and more preferably a phenolic phenolic compound obtained by linking these low molecular weight bifunctional phenolic compounds with a methylene chain from the viewpoint of heat resistance Varnish resin.

Specific examples of the phenolic novolac resin include a cresol novolak resin, a catechol novolac resin, a resorcinol novolac resin, and a hydroquinone novolak resin, and the like, and a phenolic compound is subjected to novolak. A resin obtained by dissolving two or more kinds of phenolic compounds, such as catechol resorcinol novolak resin and catechol hydroquinone novolak resin.

In particular, the phenolic novolac resin is preferably a compound containing at least one structural unit selected from the group consisting of the following general formulae (I-1) and (I-2).

In the above formulae (I-1) and (I-2), R ¹ each independently represents an alkyl group, an aryl group or an aralkyl group. The alkyl group, the aryl group, and the aralkyl group represented by R ¹ may further have a substituent, if possible. The substituent may, for example, be an alkyl group, an aryl group, a halogen atom or a hydroxyl group.

m independently represents an integer of 0 to 2, and when m is 2, two R ^{1 's} may be the same or different. In the present invention, m is preferably 0 or 1 independently, and preferably 0.

Further, n each independently represents an integer of 1 to 7.

In the above formulae (I-1) and (I-2), R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group. The alkyl group, the aryl group, and the aralkyl group represented by R ² and R ³ may further have a substituent, if possible. The substituent may, for example, be an alkyl group, an aryl group, a halogen atom or a hydroxyl group.

From the viewpoint of preserving stability and thermal conductivity, R ² and R ³ in the present invention are preferably a hydrogen atom, an alkyl group or an aryl group, and a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a carbon number of 6 The aryl group of ~12 is preferred, and the hydrogen atom is more preferred.

Further, from the viewpoint of heat resistance, at least one of R ² and R ³ is preferably an aryl group, and an aryl group having 6 to 12 carbon atoms is preferred.

Further, the above aryl group may contain a hetero atom in the aromatic group, and a heteroaryl group having a total number of hetero atoms and carbon of 6 to 12 is preferred.

The curing agent of the present invention may contain a single compound having a structural unit represented by the formula (I-1) or (I-2), and may contain two or more kinds. It is preferred to contain at least a compound having a structural unit derived from resorcin according to the formula (I-1).

The compound having the structural unit represented by the formula (I-1) may further contain at least one partial structure derived from a phenolic compound other than resorcin. Examples of the phenolic compound other than resorcinol in the above formula (I-1) include phenol, cresol, catechol, hydroquinone, 1,2,3-trihydroxybenzene, 1,2,4. - Trihydroxybenzene, 1,3,5-trihydroxybenzene, and the like. In the present invention, the partial structure derived from these phenolic compounds may be contained alone or in combination of two or more.

Further, in the structure sheet derived from catechol represented by the above formula (I-2) The compound of the element may also contain at least one partial structure derived from a phenolic compound other than catechol.

Here, the partial structure derived from a phenol type compound means a monovalent or divalent group which consists of removing one or two hydrogen atoms from the benzene ring part of a phenol type compound. Further, the position at which the hydrogen atom is removed is not particularly limited.

In the present invention, a part of the structure derived from a phenolic compound other than resorcinol is derived from phenol, cresol, catechol, hydroquinone from the viewpoints of thermal conductivity, adhesion, and storage stability. At least one selected from the group consisting of 1,2,3-trihydroxybenzene, 1,2,4-trihydroxybenzene and 1,3,5-trihydroxybenzene is preferably derived from catechol and hydroquinone. At least one selected among them is preferred.

Further, in the compound having a structural unit represented by the general formula (I-1), the content ratio of the partial structure derived from resorcin is not particularly limited. From the viewpoint of the elastic modulus, the content ratio of the partial structure derived from resorcin to the total mass of the compound having the structural unit represented by the general formula (I-1) is preferably 55 mass% or more. Further, from the viewpoint of the glass transition temperature (Tg) and the coefficient of linear expansion, the content ratio of the partial structure derived from resorcin is preferably 60% by mass or more, more preferably 80% by mass or more, and thermal conductivity. From the viewpoint of viewpoint, it is more preferably 90% by mass or more.

In addition, the phenolic novolak resin preferably contains a compound having a partial structure represented by at least one selected from the group consisting of the following general formulae (II-1) to (II-4).

In addition, the phenolic novolak resin preferably contains a compound having a partial structure represented by at least one selected from the group consisting of the following general formulae (II-1) to (II-4).

In the above formulae (II-1) to (II-2), m and n each independently represent a positive number, and represent the number of repetitions of each repeating unit. Ar represents a group represented by any one of the formulae (II-a) and (II-b).

In the above formulae (II-a) and (II-b), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom or a hydroxyl group. R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

The curing agent having a partial structure represented by at least one of the above formulas (II-1) to (II-4) can be produced by a method in which a bifunctional phenolic compound is subjected to novolak treatment and then described. .

The partial structure represented by the above formula (II-1) to (II-4) may be contained as a main chain skeleton of the curing agent, and may be contained as a part of the side chain. Further, each of the repeating units constituting the partial structure represented by any one of the above formulas (II-1) to (II-4) may be randomly contained or may be contained in a regular manner, and It can be contained in the form of a block.

Further, in the above formula (II-1) to (II-4), the substitution position of the hydroxyl group is not particularly limited as long as it is on the aromatic ring.

Each of the general formulae of the above formulae (II-1) to (II-4), and a plurality of Ar, may be the same atomic group, or may contain two or more kinds of atomic groups. Further, Ar represents a group represented by any one of the above formulae (II-a) and (II-b).

In the above formulae (II-a) and (II-b), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom or a hydroxyl group, and from the viewpoint of thermal conductivity, a hydroxyl group is preferred. Further, the substitution positions of R ¹¹ and R ¹⁴ are not particularly limited.

Further, in the above formulae (II-a) and (II-b), R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. In the above R ¹² and R ¹³ , the alkyl group having 1 to 8 carbon atoms may, for example, be a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tertiary butyl group, a pentyl group or a hexyl group. Heptyl, and octyl. Further, in the above formulae (II-a) and (II-b), the substitution positions of R ¹² and R ¹³ are not particularly limited.

In the above formulae (II-a) and (II-b), Ar is derived from a dihydroxybenzene-derived group (the above formula (II) from the viewpoint of attaining the effects of the present invention, particularly excellent thermal conductivity. -a), wherein R ¹¹ is a hydroxyl group and R ¹² and R ¹³ are a hydrogen atom; and a group derived from a dihydroxynaphthalene group (in the above formula II-b), R ¹⁴ is a hydroxyl group) At least one is preferred.

Here, the "dihydroxybenzene-derived group" means a divalent group formed by removing two hydrogen atoms from the aromatic ring portion of dihydroxybenzene, and the position at which the hydrogen atom is removed is not particularly limited. In addition, "dihydroxynaphthalene-based group" and the like have the same meaning.

In addition, from the productivity and fluidity of the aforementioned epoxy resin composition From the viewpoint, Ar is preferably a group derived from dihydroxybenzene, and is derived from a group derived from 1,2-dihydroxybenzene (catechol) and derived from 1,3-dihydroxybenzene (resorcinol). At least one selected from the group consisting of) is better. Further, from the viewpoint of particularly improving the thermal conductivity, Ar is preferably contained at least a group derived from resorcin.

Further, from the viewpoint of particularly improving the thermal conductivity, it is preferred to repeat the structural unit represented by the number n to contain a group derived from resorcin.

The content of the structural unit containing a resorcinol-based group is 55 in the total mass of the compound having a partial structure represented by at least one of the general formulae (II-1) to (II-4). The mass% or more is preferably 60% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

In the above formulae (II-1) to (II-4), from the viewpoint of fluidity, m and n are preferably m/n = 20/1 to 1/5, and 20/1 to 5/. 1 is better, preferably 20/1~10/1. Further, from the viewpoint of fluidity, (m + n) is preferably 20 or less, more preferably 15 or less, and still more preferably 10 or less.

Further, the lower limit of (m+n) is not particularly limited.

The phenolic novolak resin having a partial structure represented by at least one of the general formulae (II-1) to (II-4) is particularly preferable to a resin obtained by simply performing novolak-forming When Ar is at least one of a substituted or unsubstituted dihydroxybenzene and a substituted or unsubstituted dihydroxynaphthalene, there is a tendency that it is easier to synthesize and a hardener having a low softening point can be obtained. Therefore, there is an advantage that it is easy to manufacture and process a resin composition containing such a resin.

Further, the phenolic novolak resin having a partial structure represented by any one of the above formulas (II-1) to (II-4) can be subjected to field desorption ionization mass spectrometry (FD-MS) ) to easily identify the aforementioned partial structure as its fragment component.

In the present invention, the phenolic novolak resin having a partial structure represented by any one of the above formulas (II-1) to (II-4) is not particularly limited in molecular weight. From the viewpoint of fluidity, the number average molecular weight (Mn) is preferably 2,000 or less, more preferably 1,500 or less, and still more preferably 350 or more and 1,500 or less. Further, the weight average molecular weight (Mw) is preferably 2,000 or less, more preferably 1,500 or less, still more preferably 400 or more and 1,500 or less.

These Mn and Mw were measured by a general method using GPC (Gel Permeation Chromatograph).

In the present invention, the phenolic novolak resin having a partial structure represented by any one of the above formulas (II-1) to (II-4) has no particular limitation on the hydroxyl group equivalent. The hydroxyl group equivalent is preferably 50 or more and 150 or less from the viewpoint of crosslinking density in terms of heat resistance, and is preferably 50 or more and 120 or less, more preferably 55 or more and 120 or less.

In the present invention, the phenol novolak resin may contain a phenolic compound constituting the phenol novolak resin. The content ratio of the phenolic compound constituting the phenolic novolak resin, that is, the monomer content (hereinafter also referred to as "monomer content ratio") is not particularly limited. From the viewpoint of thermal conductivity, heat resistance and formability, it is preferably 5% by mass to 80% by mass, more preferably 15% by mass to 60% by mass, even more preferably 20% by mass to 50% by mass.

When the content of the monomer is 80% by mass or less, the monomer which does not contribute to the crosslinking during the hardening reaction is reduced, and the high molecular weight body which is crosslinked is increased, so that a higher-order structure having a higher density is formed and improved. Thermal conductivity. In addition, the monomer content ratio is 5% by mass or more, and it is easy to flow during molding, so that the adhesion to the filler is further improved, and further excellent can be achieved. Thermal conductivity and heat resistance.

When the foregoing resin composition contains a hardener, the content of the hardener in the resin composition is not particularly limited. For example, when the curing agent is an amine-based curing agent, the ratio of the equivalent of the active hydrogen of the amine-based curing agent (amine equivalent) to the epoxy equivalent of the liquid-based epoxy resin (amine equivalent/epoxide equivalent) is 0.5~ 2 is better, preferably 0.8 to 1.2. Further, when the curing agent is a phenolic curing agent, the ratio of the equivalent hydrogen (phenolic hydroxyl equivalent) of the phenolic hydroxyl group to the epoxy equivalent of the liquid crystal-containing epoxy resin (phenolic hydroxyl equivalent/epoxy equivalent) It is preferably 0.5 to 2, preferably 0.8 to 1.2.

(hardening accelerator)

When a phenolic curing agent is used in the above resin composition, a curing accelerator may be used in combination as needed. With a hardening accelerator, it can be hardened more fully. The type and amount of the curing accelerator are not particularly limited, and an appropriate compound can be selected from the viewpoints of the reaction rate, the reaction temperature, and the storage property. Specific examples of the curing accelerator include, for example, an imidazole compound, an organic phosphorus compound, a tertiary amine, and a quaternary ammonium salt. These may be used alone or in combination of two or more.

Among them, at least one selected from the group consisting of an organic phosphine compound and a complex compound formed of an organic phosphine compound and an organoboron compound is preferred from the viewpoint of heat resistance.

Specific examples of the organic phosphine compound include triphenylphosphine, diphenyl (p-tolyl) phosphine, stilbene (alkylphenyl) phosphine, arsenic (alkoxyphenyl) phosphine, and hydrazine (alkyl-alkane). Oxyphenyl)phosphine, cis (dialkylphenyl)phosphine, cis (trialkylphenyl)phosphine, cis (tetraalkylphenyl)phosphine, cis (dialkoxyphenyl)phosphine, ginseng Trialkoxyphenyl) Phosphine, cis (tetraalkoxyphenyl) phosphine, trialkyl phosphine, dialkyl aryl phosphine, alkyl diaryl phosphine, and the like.

Further, specific examples of the complex formed of the organic phosphine compound and the organoboron compound include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetrakis(tolyl)borate, and tetraphenylboronic acid. Butyl hydrazine, tetraphenylphosphonium n-butyltriphenylborate, butyltriphenylphosphonium tetraphenylborate, methyltributylphosphonium tetraphenylborate, and the like.

The curing accelerator may be used alone or in combination of two or more. A method of efficiently producing a semi-hardened resin composition and a cured resin composition, which will be described later, may be, for example, a method in which two kinds of curing accelerators having different reaction starting temperatures and reaction rates of an epoxy resin monomer and a novolac resin are used in combination. .

When two or more types of hardening accelerators are used in combination, the mixing ratio is not particularly limited, and can be determined depending on characteristics required for the semi-cured resin composition (for example, what degree of flexibility is required).

When the resin composition contains a hardening accelerator, the content of the hardening accelerator in the resin composition is not particularly limited. The content of the curing accelerator is preferably 0.5% by mass to 1.5% by mass based on the total mass of the thermosetting resin having a liquid crystal group in the molecule and the curing agent, and is 0.5% by mass to 1% by mass. % is more preferable, and it is more preferably 0.75 mass% to 1 mass%.

(decane coupling agent)

The resin composition further preferably contains at least one decane coupling agent. The effect of adding a decane coupling agent produces a function of forming a covalent bond (corresponding to a binder) between the surface of the first filler or the second filler and the thermosetting resin surrounding the periphery of the first filler or the second filler, thereby contributing to efficient production. The role of heat transfer, and further It also hinders the penetration of moisture and also contributes to the improvement of insulation reliability.

The type of the decane coupling agent is not particularly limited, and a commercially available product can be used. In view of the compatibility between the thermosetting resin (preferably epoxy resin) and the hardener contained as needed, and the reduction of the heat conduction loss at the interface between the resin and the filler, in the present invention, it is preferred. It is a decane coupling agent having an epoxy group, an amine group, a mercapto group, a urea group or a hydroxyl group at the end.

Specific examples of the decane coupling agent include, for example, 3-glycidoxypropyltrimethoxydecane, 3-epoxypropoxytriethoxydecane, and 3-glycidoxypropylmethyldiethyl. Oxydecane, 3-glycidoxypropylmethyldimethoxydecane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane; 3-aminopropyltriethoxylate Decane, 3-(2-aminoethyl)aminopropyltrimethoxydecane, 3-(2-aminoethyl)aminopropyltrimethoxydecane, 3-aminopropyltrimethoxydecane , 3-anilinopropyltrimethoxydecane; 3-mercaptopropyltrimethoxydecane, 3-mercaptotriethoxydecane; 3-ureidopropyltriethoxydecane, and the like. Further, for example, a decane couplant oligomer represented by SC-6000KS2 (manufactured by Hitachi Chemical Coated Sand Co., Ltd.) may be mentioned.

These decane coupling agents may be used alone or in combination of two or more.

(Organic solvents)

The resin composition may further contain at least one organic solvent. The inclusion of an organic solvent makes it suitable for a variety of forming steps. As the organic solvent, an organic solvent generally used can be used. Specific examples thereof include an alcohol solvent, an ether solvent, a ketone solvent, a guanamine solvent, an aromatic hydrocarbon solvent, an ester solvent, and a nitrile solvent. For example, methyl isobutyl ketone, dimethyl acetamide, dimethylformamide, dimethyl sulfoxide, N- can be used. Methyl-2-pyrrolidone, γ-butyrolactone, sulfolane, cyclohexanone, methyl ethyl ketone, and the like. These may be used singly or in combination of two or more kinds to prepare a mixed solvent.

(other ingredients)

The resin composition in the present invention may contain other components in addition to the above components as needed. For example, an elastomer, a dispersing agent, etc. are mentioned. The elastomer may, for example, be an acrylic resin, and more specifically, for example, a homopolymer or a copolymer derived from (meth)acrylic acid or (meth)acrylic acid ester. Examples of the dispersing agent include AJISPER series manufactured by Ajinomoto Fine-Tech Co., Ltd., HIPLAAD series manufactured by Nanben Chemical Co., Ltd., and HOMOGENOL series manufactured by Kao Corporation. These dispersing agents can be used in combination of two or more.

<Semi-hardened resin composition>

The semi-hardened resin composition of the present invention is derived from the resin composition described above, and is obtained by subjecting the resin composition to a semi-hardening treatment. In the semi-cured resin composition, for example, when the composition is formed into a sheet shape, the handleability is further improved as compared with the resin sheet composed of the resin composition not subjected to the semi-hardening treatment.

Here, the semi-hardened resin composition has a characteristic that the viscosity of the semi-cured resin composition is 10 ⁴ Pa at normal temperature (25 to 30 ° C). s~10 ⁵ Pa. s, in contrast, reduced to 10 ² Pa at 100 ° C. s~10 ³ Pa. s. Further, the hardened resin composition after curing described later is not melted by heating. Further, the viscosity is measured by dynamic viscoelasticity measurement (DMA (dynamic mechanical analysis)) (for example, ARES-2KSTD manufactured by TA Instruments). Further, the measurement conditions were as follows: a frequency of 1 Hz, a load of 40 g, and a temperature increase rate of 3 ° C/min, which were carried out by a shear test.

The semi-hardening treatment may be, for example, a method of heating the resin composition at a temperature of 100 ° C to 200 ° C for 1 minute to 30 minutes.

<hardened resin composition>

The cured resin composition of the present invention is derived from the resin composition and is obtained by subjecting the resin composition to a curing treatment. The cured resin composition is excellent in thermal conductivity and insulation properties. The reason for this is that, for example, a thermosetting resin having a liquid crystal group in a molecule contained in the resin composition is combined with a specific filler, and as a result, a high-order structure has been formed.

The cured resin composition can be produced by subjecting the resin composition in an uncured state or the semi-hardened resin composition to a hardening treatment. The method of the above-mentioned hardening treatment can be appropriately selected depending on the constitution of the resin composition, the purpose of curing the resin composition, and the like, and is preferably heated/pressurized.

For example, when the resin composition in the uncured state or the semi-hardened resin composition is heated at a temperature of 100 ° C to 250 ° C for 1 hour to 10 hours, a hardened resin composition can be obtained to heat at 130 ° C to 230 ° C. Hours ~ 8 hours is better.

<Resin sheet>

The resin sheet of the present invention is obtained by molding the resin composition into a sheet shape. The resin sheet can be produced, for example, by applying the resin composition onto a release film and removing the solvent contained as needed. The resin sheet is formed of the above-described resin composition, and is excellent in thermal conductivity, fluidity, and flexibility.

The thickness of the foregoing resin sheet is not particularly limited and can be used for the purpose. Appropriate choice. For example, the thickness of the resin sheet can be set to 50 μm to 500 μm, and it is preferably 80 μm to 300 μm from the viewpoint of thermal conductivity, electrical insulation, and flexibility.

The resin sheet can be produced by, for example, applying a varnish-like resin composition to a release film such as a PET (poly(ethylene terephthalate) or polyethylene terephthalate film) (hereinafter also referred to as " After the resin varnish is formed to form a coating layer, at least a part of the organic solvent is removed from the coating layer, and the varnish-like resin composition is added with methyl ethyl ketone or cyclohexene to the resin composition. It is prepared by using an organic solvent such as a ketone.

The application of the resin varnish can be carried out by a conventional method. Specifically, for example, a comma coating, a die coating, a lip coating, a gravure coating, and the like can be exemplified. The coating method for forming the resin composition layer to a predetermined thickness is to apply a method of applying a coated object through a blade coating method between the gaps; and applying a mold for adjusting the flow rate of the resin varnish from the nozzle. Coating method, etc. For example, when the thickness of the coating layer (resin composition layer) before drying is 50 μm to 500 μm, it is preferred to use a doctor blade coating method.

The drying method is not particularly limited as long as at least a part of the organic solvent contained in the resin varnish can be removed, and can be appropriately selected from the organic solvent contained in the resin varnish from the drying method generally used. Generally, for example, a method of performing heat treatment at about 80 ° C to 150 ° C can be mentioned.

The resin composition layer of the resin sheet has flexibility because the hardening reaction hardly proceeds, but lacks flexibility as a sheet, and lacks sheet independence in a state where the support, that is, the PET film is removed. It is difficult to handle.

The resin sheet is preferably a semi-cured resin composition obtained by semi-hardening a resin composition constituting the resin sheet. In other words, the resin sheet is preferably a B-stage sheet which is further subjected to heat treatment until it is in a semi-hardened state (B-stage state). The resin sheet is composed of a semi-cured resin composition obtained by semi-hardening the resin composition, and is excellent in thermal conductivity and electrical insulation, and is excellent in flexibility and usable time of the B-stage sheet.

Here, the B-stage sheet has the following characteristics: its viscosity is 10 ⁴ Pa at normal temperature (25 to 30 ° C). s~10 ⁵ Pa. s, in contrast, reduced to 10 ² Pa at 100 ° C. s~10 ³ Pa. s. Further, the hardened resin composition after curing described later is not melted by heating. Further, the above viscosity was measured by DMA (frequency 1 Hz, load 40 g, temperature increase rate 3 ° C/min).

The condition for heat-treating the resin sheet is not particularly limited as long as the resin composition layer can be in the B-stage state, and can be appropriately selected depending on the configuration of the resin composition. In the heat treatment, the heat treatment method selected from the group consisting of thermal vacuum pressing, hot roll lamination, and the like is used for the purpose of removing voids (voids) in the resin composition layer generated during coating. It is better. Thereby, a flat B-stage sheet can be efficiently produced.

Specifically, it can be carried out in the following manner, for example, under reduced pressure (for example, 1 kPa), temperature of 100 ° C to 200 ° C, and heating/pressurization treatment at a pressure of 1 MPa to 20 MPa for 1 second to 90 seconds. The resin composition is semi-hardened until the B-stage state.

In addition, when the resin composition is semi-hardened until the B-stage state, two sheets of the coated/dried resin sheet are bonded together, and then the above-mentioned addition is performed. The heat/pressure treatment, the hardened resin composition obtained by the method described later, exhibits a higher thermal conductivity. At this time, it is necessary to bond the coated surface (the surface which is the upper surface at the time of coating, that is, the surface opposite to the surface in contact with the PET film), thereby making the both surfaces of the resin sheet flatter.

The thickness of the B-stage sheet can be appropriately selected depending on the purpose, and can be, for example, 50 μm to 500 μm, and preferably 80 μm to 300 μm from the viewpoint of thermal conductivity, electrical insulation, and flexibility. Further, it is also possible to produce a resin sheet of two or more layers by one surface layer.

When the B-stage sheet is formed using a resin composition containing a solvent, the solvent residual ratio in the B-stage sheet is preferably 2.0% by mass or less from the viewpoint that bubbles are formed when gas is released during curing. It is preferably 1.0% by mass or less, more preferably 0.8% by mass or less.

The solvent residual ratio was determined from the mass change before and after drying after cutting the B-stage sheet into 40 mm square and drying in a thermostat preheated to 190 ° C for 2 hours.

The fluidity of the aforementioned B-stage sheet is excellent. Specifically, the flow amount of the B-stage sheet is preferably 130% to 210%, more preferably 150% to 200%. This flow amount is an indicator of the melt fluidity at the time of hot press bonding. When the amount of flow is 130% or more, sufficient embedding property can be obtained, and if the amount of flow is 210% or less, burrs due to excessive flow can be suppressed.

The flow amount is calculated as follows: under the condition of 1 atm, the temperature of 180 ° C, and the pressure of 15 MPa, the area change rate of the B-stage sheet before and after pressing the sample for 1 minute, the sample is A 200 μm thick B-stage sheet was punched into 10 mm square. The area change rate is obtained by scanning a sample outside the image using a scanner of 300 DPI or more, and performing binarization processing by an image analysis software (Adobe Photoshop), and determining the rate of change from the area (number of pixels). .

Flow amount (%) = (area of B-stage sheet after pressing) / (area of B-stage sheet before pressing)

Further, the resin sheet may be a cured resin composition obtained by curing the resin composition. The resin sheet composed of the cured resin composition can be produced by curing the resin sheet or the B-stage sheet in an uncured state. The method of the above-mentioned hardening treatment can be appropriately selected depending on the constitution of the resin composition, the purpose of curing the resin composition, and the like, and is preferably heated/pressurized.

The resin sheet composed of the cured resin composition can be obtained in the following manner, for example, heating the resin sheet or the B-stage sheet in an uncured state at 100 ° C to 250 ° C for 1 hour to 10 hours at 130 ° C to 230 ° C. Heating for 1 hour to 8 hours is preferred. Further, it is preferred to carry out the above heating while applying a pressure of 1 MPa to 20 MPa.

Further, an example of a method of producing a resin sheet composed of a cured resin composition having excellent thermal conductivity is as follows: First, a copper foil having a roughened surface on one side (thickness: 80 μm to 120 μm) In the state where the roughened surface is in contact with each other, the B-stage sheet is heated/pressurized for 3 minutes to 10 minutes at a temperature of 130 ° C to 230 ° C under a pressure of 1 MPa to 20 MPa. The B-stage sheet is adhered to the copper foil. Then, after heating at 130 ° C to 230 ° C for 1 hour to 8 hours, the obtained copper foil is attached by etching treatment. The copper foil portion of the resin sheet is partially removed, and a resin sheet composed of a cured resin composition is obtained.

<Prepreg>

The prepreg according to the present invention has a fibrous base material and the resin composition, and the resin composition is impregnated into the fibrous base material. With such a configuration, it is possible to form a prepreg which is excellent in thermal conductivity and insulation. Further, since the resin composition containing the α-alumina filler is improved in shakeability, deposition of the second filler in the coating step or the impregnation step described later can be suppressed. Therefore, it is possible to suppress the second filler from being distributed in the thickness direction of the prepreg, and as a result, it is possible to obtain a prepreg excellent in thermal conductivity and insulation.

The fiber base material constituting the prepreg is not particularly limited as long as it is generally used for producing a metal foil-clad laminate and a multilayer printed wiring board, and a fiber base material such as woven fabric or non-woven fabric is generally used.

The pore diameter of the aforementioned fibrous base material is not particularly limited. From the viewpoint of thermal conductivity and insulation, the pore diameter is preferably 5 times or more the average particle diameter (D50) of the second filler. Further, when the particle size distribution curve of the second filler has a plurality of peaks, the pore diameter is preferably 5 or more times the particle diameter corresponding to the peak of the largest particle diameter.

The material of the fibrous substrate is not particularly limited. Specific examples thereof include inorganic fibers such as glass, alumina, boron, yttrium aluminum glass, yttrium glass, TYRANNO, tantalum carbide, tantalum nitride, and zirconia; and linaloamine, polyetheretherketone, and polyether oxime. Organic fibers such as amines, polyether oximes, carbons, celluloses, etc.; and blended systems thereof. Among them, a woven fabric of glass fiber is preferred. Thereby, for example, when a printed wiring board is formed using a prepreg, it is possible to obtain flexibility and to be arbitrarily Bent printed circuit board. Further, it is also possible to reduce the situation in which the size of the printed wiring board changes depending on temperature changes or moisture absorption in the manufacturing steps.

The thickness of the aforementioned fibrous base material is not particularly limited. From the viewpoint of imparting more favorable flexibility, it is preferably 30 μm or less, and more preferably 15 μm or less from the viewpoint of impregnation. The lower limit of the thickness of the fibrous base material is not particularly limited and is usually about 5 μm.

The impregnation amount (content ratio) of the resin composition in the prepreg is preferably 50% by mass to 99.9% by mass based on the total mass of the fiber base material and the resin composition.

The prepreg can be produced by impregnating the fiber substrate with the resin composition prepared in the same manner as described above and preparing the varnish, and heat-treating at 80 ° C to 150 ° C to at least a part of the organic solvent. Remove.

Further, the method of impregnating the resin composition into the fibrous base material is not particularly limited. For example, a method of coating by a coating machine can be mentioned. The detailed method may, for example, be a vertical coating method in which a fibrous substrate is immersed in a resin composition, and a resin coating is applied to a support film, and then the fibrous substrate is pressed and impregnated into a horizontal shape. Painting method, etc. From the viewpoint of suppressing the local presence of the second filler in the fibrous base material, a horizontal coating method is preferred.

The prepreg can be used before being laminated or pasted by heat pressing treatment using a roll laminator or the like before smoothing or pasting. The method of hot pressing treatment is the same as that exemplified in the above-described method for producing a B-stage sheet. Further, the processing conditions such as the heating temperature, the degree of pressure reduction, and the pressurizing pressure in the hot press treatment of the prepreg are also the heating/pressurization of the aforementioned B-stage sheet. The conditions listed in the process are the same.

When the prepreg is prepared by using a resin composition containing a solvent, the residual ratio of the solvent in the prepreg is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and still more preferably 0.8% by mass or less.

The solvent residual ratio was determined from the mass change before and after drying after the prepreg was cut into 40 mm squares and dried in a thermostat previously heated to 190 ° C for 2 hours.

<Laminated board>

The laminated board of the present invention has an adherend material, a semi-hardened resin composition layer or a cured resin composition layer, and the semi-hardened resin composition layer or the cured resin composition layer is disposed on the adherend. The semi-hardened resin composition layer and the cured resin composition layer are derived from at least one selected from the group consisting of a resin composition layer, the resin sheet, and the prepreg, and the resin composition layer is composed of the resin composition. Composition. The semi-hardened resin composition layer or the cured resin composition layer formed of the resin composition can be formed into a laminate having excellent thermal conductivity and insulation properties.

Examples of the above-mentioned adherend material include a metal foil, a metal plate, and the like. The adherend material may be provided only on one surface of the semi-hardened resin composition layer or the cured resin composition layer or on both surfaces of the semi-hardened resin composition layer or the cured resin composition layer.

The metal foil is not particularly limited, and can be appropriately selected from metal foils generally used. Specifically, for example, a gold foil, a copper foil, an aluminum foil, etc. are used, and a copper foil is generally used. The thickness of the metal foil is not particularly limited as long as it is 1 μm to 200 μm, and can be selected in accordance with the electric power used. Choose a better thickness.

Further, as the metal foil, nickel, nickel-phosphorus, nickel-tin alloy, nickel-iron alloy, lead, lead-tin alloy or the like may be used as an intermediate layer, and copper of 0.5 μm to 15 μm may be provided on both surfaces thereof. A composite foil of a three-layer structure in which a layer and a copper layer of 10 μm to 150 μm are formed; or a composite foil of a two-layer structure in which aluminum and a copper foil are composited.

The metal plate is preferably made of a metal material having a high thermal conductivity and a large heat capacity. Specifically, for example, copper, aluminum, iron, and an alloy used for a lead frame can be exemplified.

The thickness of the metal plate can be appropriately selected depending on the application. For example, the metal plate can be selected in accordance with the purpose of selecting aluminum when light weight or workability is preferred, and selecting copper when heat dissipation is preferred.

In the form of a semi-hardened resin composition layer or a cured resin composition layer, one layer derived from the resin composition layer, the resin sheet, or the prepreg may be used as the laminated layer. In the laminated layer, two or more layers derived from the resin composition layer, the resin sheet, or the prepreg are used as a semi-hardened resin composition layer or a cured resin composition layer. In the case of having two or more layers of the semi-hardened resin composition layer or the cured resin composition layer, it may be in the form of two or more layers of the resin composition layer and two or more of the resin sheets. The form and the form of the prepreg having two or more sheets. In addition, any two or more of the resin composition layer, the resin sheet, and the prepreg may be combined.

The aforementioned laminate is obtained in the following manner, for example: in an adhesive material The resin composition is applied to the material to form a resin composition layer, and the resin composition layer is subjected to heating and pressure treatment to semi-harden or harden the resin composition layer and adhere it to the adherend. Or a laminate obtained by laminating the resin sheet or the prepreg with the adhesive material, and heating and pressing the laminate to semi-harden the resin sheet or the prepreg or Hardens and adheres to the material to be adhered.

The method of hardening or hardening the resin composition layer, the resin sheet, and the prepreg is not particularly limited. For example, heating and pressure treatment are preferred. The heating temperature in the heating and pressurizing treatment is not particularly limited. It is usually in the range of 100 ° C to 250 ° C, preferably in the range of 130 ° C to 230 ° C. Further, the pressurization conditions in the heating and pressurization treatment are not particularly limited. It is usually in the range of 1 MPa to 20 MPa, preferably in the range of 1 MPa to 15 MPa. Further, the heating and pressurizing treatment is preferably performed by vacuum pressing.

The thickness of the laminate is preferably 500 μm or less, preferably 100 μm to 300 μm. When the thickness is 500 μm or less, the flexibility is excellent, and cracking during bending can be suppressed, and when the thickness is 300 μm or less, this tendency can be observed more. Further, when the thickness is 100 μm or more, the workability is excellent.

<Resin cured with metal foil, metal substrate>

As an example of the laminated plate, for example, a resin cured product with a metal foil and a metal substrate can be used, and these can be used for producing a printed wiring board to be described later.

The cured metal foil-attached resin is composed of two metal foils as the adherend material in the laminate. Specifically, the composition of the cured metal foil-attached resin is sequentially laminated: a metal foil, front The hardened resin composition layer and another metal foil are described.

The detailed description of the metal foil and the cured resin composition layer constituting the cured metal foil-attached resin is as described above.

Further, the metal substrate is configured by using a metal foil and a metal plate as an adhering material in the laminated plate. Specifically, the metal substrate is formed by sequentially laminating the metal foil, the cured resin composition layer, and the metal plate.

The detailed description of the metal foil and the cured resin composition layer constituting the metal substrate is as described above.

The metal plate is not particularly limited and can be appropriately selected from metal plates generally used. Specifically, for example, an aluminum plate, an iron plate, or the like can be mentioned. The thickness of the metal plate is not particularly limited. From the viewpoint of workability, the thickness is preferably 0.5 mm or more and 5 mm or less.

Further, from the viewpoint of improving productivity, the aforementioned metal plate is preferably cut to a size to be used after being made larger than a desired portion and mounted with an electronic component. Therefore, the metal plate used for the metal substrate is preferably excellent in cutting workability.

When aluminum is used as the aforementioned metal plate, the material thereof can be selected from aluminum or an alloy containing aluminum as a main component. Aluminum or an alloy containing aluminum as a main component can be obtained in various kinds depending on its chemical composition and heat treatment conditions. Among them, it is preferable to select a type having high workability such as easy cutting and excellent strength.

<Printed circuit board>

The printed wiring board of the present invention is formed by sequentially laminating a metal plate, a hardened resin composition layer, and a wiring layer. The aforementioned hardened resin composition layer is derived from At least one selected from the group consisting of a resin composition layer, the resin sheet, and the prepreg, the resin composition layer is composed of the resin composition. The cured resin composition layer formed of the resin composition can be formed into a printed wiring board excellent in thermal conductivity and insulation.

The printed wiring board can be manufactured by performing a circuit processing on a metal foil which is at least one metal foil of the cured metal foil-attached resin or a metal foil in a metal substrate. In the circuit processing of the aforementioned metal foil, a general method of photolithography can be applied.

The preferred embodiment of the printed wiring board is, for example, the same as the printed wiring board described in paragraph 0064 of JP-A-2009-214525 and paragraphs 0056 to 0059 of JP-A-2009-275086. Printed circuit board.

<Power semiconductor device>

A power semiconductor device according to the present invention includes: a semiconductor module in which a metal plate, a solder layer, and a semiconductor wafer are sequentially laminated; a heat dissipating member; and a cured body of the resin sheet, which are disposed on the metal plate of the semiconductor module and the foregoing The hardened body of the resin sheet between the heat radiating members is a sheet-like formed body of the resin composition of the present invention.

In the power semiconductor device described above, only the semiconductor module portion may be sealed by a sealing material or the like, or the entire power semiconductor module may be molded by a molding resin or the like. Hereinafter, an example of the above power semiconductor device will be described using a drawing.

Fig. 11 is a schematic cross-sectional view showing an example of a configuration of a power semiconductor device. In FIG. 11, the semiconductor module is sequentially laminated with a metal plate 106, a solder layer 110, and a semiconductor wafer 108, and is in the semiconductor module. A hardened body 102 of a resin sheet is disposed between the metal plate 106 and the heat dissipation base substrate 104, and a portion of the semiconductor module is sealed by the sealing material 114.

In addition, Fig. 12 is a schematic cross-sectional view showing another example of the configuration of the power semiconductor device. In FIG. 12, the semiconductor module is sequentially laminated with a metal plate 106, a solder layer 110, and a semiconductor wafer 108, and a hardened body of a resin sheet is disposed between the metal plate 106 and the heat dissipation base substrate 104 in the semiconductor module. 102, and the semiconductor module and the heat dissipation base substrate 104 are molded by the mold resin 112.

As described above, the sheet-like molded body of the resin composition of the present invention, that is, the resin sheet, can be used as a heat-sensitive adhesive layer between the semiconductor module and the heat-radiating base substrate as shown in Fig. 11 . Further, when the entire power semiconductor device is molded as shown in Fig. 12, it can also be used as a heat dissipation material between the heat dissipation base substrate and the metal plate.

[Examples]

The invention is specifically illustrated by the following examples, but the invention is not limited by the examples. In addition, "parts" and "%" are the quality standards unless otherwise specified.

The materials used to make the resin composition and the abbreviations thereof are shown below.

(first filler)

●HIT-70[α-alumina, manufactured by Sumitomo Chemical Co., Ltd., average particle size: 150 nm]

●AA-04[α-alumina, Sumitomo Chemical Co., Ltd., average particle size: 400 nm]

(second filler)

●HP-40[boron nitride, water island alloy iron (stock), average particle size: 18 μm]

●FAN-f30[Aluminum nitride, Furukawa Electronics Co., Ltd., average particle size: 30 μm]

●FAN-f05[Aluminum nitride, Furukawa Electronics Co., Ltd., average particle size: 5 μm]

(third filler)

●Shapal H [aluminum nitride, manufactured by TOKUYAMA Co., Ltd., average particle size: 0.6 μm]

(thermosetting resin)

- Resin A described below (refer to Japanese Patent No. 4619770)

- Resin B described below (refer to Japanese Patent No. 4619770)

- Resin C (refer to Japanese Laid-Open Patent Publication No. 2011-74366)

- The following resin D (refer to Japanese Laid-Open Patent Publication No. 2011-74366)

(hardener)

●CRN [catechol phenol resorcinol (feed ratio: 5/95) resin, manufactured by Hitachi Chemical Co., Ltd., containing 50% cyclohexanone]

<Synthesis method of CRN>

In a separable flask equipped with a stirrer, a condenser and a thermometer, 3 ml of resorcinol, 627 g of catechol, 33 g of catechol, 316.2 g of 37% formaldehyde, 15 g of oxalic acid, 300 g of water, and one side in an oil bath were added. The heating side is heated to 100 °C. The mixture was refluxed at about 104 ° C, and the reaction was continued at reflux temperature for 4 hours. Then, while the water was distilled off, the temperature in the flask was raised to 170 °C. The reaction was continued for 8 hours while maintaining 170 °C. After the reaction, the mixture was concentrated under reduced pressure for 20 minutes to remove water or the like in the system to obtain a target phenol resin CRN.

Further, after confirming the structure of the obtained CRN by FD-MS, it was confirmed that all the partial structures represented by the general formulae (II-1) to (II-4) were present.

Further, under the above reaction conditions, a compound having a partial structure represented by the general formula (II-1) should be initially produced, and the compound is further subjected to a dehydration reaction to form a compound of the formula (II-1) to (II). a compound of a partial structure shown in at least one of -4).

The obtained CRN was measured for Mn and Mw in the following manner. The measurement of Mn and Mw is performed using a high-performance liquid layer made by Hitachi. The analyzer L6000 and the data processing device C-R4A manufactured by Shimadzu Corporation were used. For the GPC column for analysis, G2000HXL and G3000HXL made by Tosoh Corporation were used. The sample concentration was 0.2% by mass, and the mobile phase was measured using tetrahydrofuran at a flow rate of 1.0 mL/min. After preparing a calibration curve using a polystyrene standard sample, the calibration curve was used to calculate Mn and Mw in terms of the value converted to polystyrene.

The obtained CRN was measured for the hydroxyl equivalent in the following manner.

The hydroxyl equivalent is measured by an ethyl chlorohydroxide-potassium hydroxide titration method. Further, since the judgment of the end point of the titration is dark because the color of the solution is dark, it is not carried out by the color development method using the indicator, but by potentiometric titration. Specifically, after the hydroxyl group of the measurement resin is subjected to acetonitrile chlorination in a pyridine solution, the excess reagent is decomposed with water, and the produced acetic acid is titrated with a potassium hydroxide/methanol solution. The resulting CRN is shown below.

CRN is a phenol resin containing a hardener (hydroxyl equivalent 62, number average molecular weight 422, weight average molecular weight 564), and the hardener has at least one of the general formulae (II-1) to (II-4) a mixture of partially structured compounds, and containing 35% of a monomer component (resorcinol) as a low molecular diluent, wherein Ar is R ¹¹ =hydroxyl in the above formula (II-a) and R ¹² = R ¹³ = a group derived from 1,2-dihydroxybenzene (catechol) and a group derived from 1,3-dihydroxybenzene (resorcinol).

(additive)

●TPP: triphenylphosphine [hardening accelerator]

●KBM-573: 3-anilinopropyltrimethoxydecane [decane coupling agent, Shin-Etsu Chemical Co., Ltd.]

(solvent)

●CHN: cyclohexanone

(support)

●PET film [Fuson Industrial Co., Ltd., 75E-0010CTR-4]

●Copper foil [Furukawa Electric Co., Ltd., thickness: 80 μm, GTS grade]

(Example 1) <Production of Resin Composition>

The first filler (α-alumina, HIT-70) was 0.45 mass%, the second filler (boron nitride, HP-40) was 70.29 mass%, the thermosetting resin (resin A) was 10.22 mass%, and the hardener (CRN) 6.30% by mass, a hardening accelerator (TPP) of 0.11% by mass, a decane coupling agent (KBM-573) of 0.07% by mass, and a solvent (CHN) of 12.56% by mass, and an epoxy obtained in the form of a resin composition containing a solvent. Resin varnish.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

<Production of B-stage sheet>

The epoxy resin varnish obtained above was applied onto a PET film by using an applicator so that the thickness after drying became 200 μm, and then dried at 100 ° C for 10 minutes. Then, hot pressing was performed by vacuum pressurization (pressurization temperature: 180 ° C, vacuum degree: 1 kPa, pressurization pressure: 15 MPa, treatment) Time: 60 seconds), and a B-stage sheet was obtained in the form of a resin sheet of a semi-hardened resin composition.

<Evaluation of the amount of liquidity>

The PET film of the B-stage sheet (thickness: 200 μm) obtained above was peeled off, punched into a 10 mm square, and pressed at a pressure of 180 ° C under a pressure of 1 MPa, and a pressure of 15 MPa was applied. Press for 1 minute. Scanning image of the sample after extrusion is scanned using a scanner of 300 DPI or higher, and the area (pixel number) before and after extrusion is subjected to binarization by image analysis software (Adobe Photoshop). To assess the amount of liquidity.

<Production of cured resin with copper foil>

After peeling off the PET film of the B-stage sheet obtained above, two sheets of copper foil were sandwiched so that the matte side thereof was opposed to the B-stage sheet, and vacuum-pressing was performed by vacuum pressurization (temperature : 180 ° C, vacuum: 1 kPa, pressurization pressure: 15 MPa, treatment time: 8 minutes). Then, the mixture was heated at 140 ° C for 2 hours, at 165 ° C for 2 hours, and further heated at 190 ° C for 2 hours under a pressure of 1 atm to obtain a cured resin with a copper foil.

<Measurement of thermal conductivity> (resin sheet cured product)

The copper foil with the cured copper foil obtained as described above is etched and removed, and the cured resin sheet is obtained in the form of a cured resin composition. The obtained resin sheet cured product was cut into 10 mm squares, and blackened by graphite spraying, and the thermal diffusivity was evaluated using a xenon flash method (LFA447 nanoflash manufactured by NETZSCH Co., Ltd.). From this value, to the density measured by the Archimedes method, and by DSC (differential scanning) The thermal conductivity of the cured resin sheet was determined by multiplying the specific heat measured by a calorimeter (a differential scanning calorimeter) (DSC Pyris 1 manufactured by Perkin Elmer Co., Ltd.).

The results are shown in Table 1.

In addition, the thermal conductivity of the resin sheet cured product obtained from the above was converted into the following formula, and the thermal conductivity of the resin portion in the cured resin sheet was determined.

1-ν=[(λmix-λres)/(λres-λfil)]×(λres/λmix) ^x

(where x=1/(1+χ)).

The results are shown in Table 1.

Λmix: thermal conductivity of resin sheet (W/mK)

Λres: thermal conductivity (W/mK) of the resin portion in the resin sheet

Λfil: thermal conductivity (W/mK) of the filler portion in the resin sheet (60 when the second filler is boron nitride, and 60 when the second filler is a mixture of boron nitride and alumina) 60, set to 130 when the second filler is aluminum nitride)

ν: volume fraction of the filler (% by volume)

χ: Shape parameter of the filler (set to 3.1 when the second filler is boron nitride and 2.2 when the second filler is aluminum nitride)

(hardened resin without filler)

The mixture obtained by mixing the thermosetting resin, the curing agent, and the curing accelerator for producing the above resin composition was melted, and then sandwiched between two aluminum plates (thickness: 200 μm), and under a pressure of 1 atm. The mixture was heated at 140 ° C for 1 hour, heated at 165 ° C for 1 hour, and further heated at 190 ° C for 1 hour to obtain a filler-free resin cured product (thickness: about 150 μm) with an aluminum plate.

Stripping the aluminum sheet from the hardened resin-free resin with the aluminum plate attached above The resin cured product obtained was evaluated for thermal diffusivity using a temperature wave thermal analyzer (ai-Phase mobile 1u manufactured by ai-Phase Co., Ltd.). From the value and the product of the density determined by the above method and the specific heat, the thermal conductivity of the cured resin-free material is determined, and the thermal conductivity is set in the cured resin sheet (hardened resin composition). The thermal conductivity of the resin portion.

The results are shown in Table 1.

<Measurement of insulation breakdown voltage>

The copper foil with the cured copper foil obtained as described above is etched and removed, and the cured resin sheet is obtained in the form of a cured resin composition. The obtained cured resin sheet was cut into a size of 100 mm square or more to prepare a sample. YST-243-100RHO manufactured by YAMAYO Tester Co., Ltd. was clamped by a cylindrical electrode having a diameter of 25 mm, and the dielectric breakdown voltage was measured in the atmosphere at a pressure increase rate of 500 V/s and room temperature. The average and minimum values of the measurement points above 5 points.

The results are shown in Table 1.

(Example 2)

The first filler (α-alumina, a mixture of 0.45 vol% HIT-70 and 11.76 vol% AA-04) 12.21% by mass, second filler (boron nitride, HP-40) 58.53 mass %, thermosetting resin (resin A) 10.22% by mass, curing agent (CRN) 6.30% by mass, hardening accelerator (TPP) 0.11% by mass, decane coupling agent (KBM-573) 0.07% by mass, and solvent (CHN) 12.56 mass% of the mixture was obtained, and the epoxy resin varnish was obtained in the form of a resin composition containing a solvent.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 7.5 vol%. Further, when the ratio of the second filler to the total volume was calculated, it was 65 vol%.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 1.

(Example 3)

The first filler (α-alumina, HIT-70) 0.45 mass%, the second filler (aluminum nitride, a mixture of 49.02 vol% FAN-f30 and 14.82 vol% FAN-f05) 63.84 mass %, third filler (aluminum nitride, Shapal H) 10.39% by mass, thermosetting resin (resin A) 7.23 mass%, hardener (CRN) 4.46 mass%, hardening accelerator (TPP) 0.08 mass%, decane coupling The agent (KBM-573) was mixed with 0.07 mass%, and the solvent (CHN) was 13.48 mass%, and the epoxy resin varnish was obtained in the form of a resin composition containing a solvent.

The density of the alumina was set to 3.97 g/cm ³ , the density of the aluminum nitride was 3.26 g/cm ³ , and the density of the mixture obtained by mixing the resin A and the CRN was set to 1.20 g/cm ³ to calculate the first filler. The ratio of the first filler to the second filler and the total volume of the thermosetting resin and the hardener was 0.37 vol%. Further, when the ratio of the second filler to the total volume was calculated, it was 64% by volume. Further, the ratio of the total volume of the second filler to the third filler to the total volume was 74% by volume.

Further, the average particle diameter (D50) of the second filler was 24 μm.

The epoxy resin varnish obtained above was used, and the conditions of hot pressing by vacuum press were changed to pressurization temperature: 150 ° C, vacuum degree: 1 kPa, pressurization pressure: 1 MPa, treatment time: 60 In the same manner as in Example 1, except that the conditions of vacuum pressure bonding by vacuum press were changed to temperature: 150 ° C, vacuum: 1 kPa, pressurization pressure: 4 MPa, and treatment time: 5 minutes. After the B-stage sheet and the cured resin with the copper foil were produced, the evaluation was performed in the same manner as above.

The results are shown in Table 1.

(Example 4)

The first filler (α-alumina, HIT-70) was 0.45 mass%, the second filler (boron nitride, HP-40) was 70.29 mass%, the thermosetting resin (resin B) was 10.22 mass%, and the hardener (CRN) 6.30% by mass, a hardening accelerator (TPP) of 0.11% by mass, a decane coupling agent (KBM-573) of 0.07% by mass, and a solvent (CHN) of 12.56% by mass, and an epoxy obtained in the form of a resin composition containing a solvent. Resin varnish.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

Except that the epoxy resin varnish obtained above was used, the same procedure as in Example 1 was carried out to prepare a B-stage sheet and a resin with a copper foil. After the compound, the evaluation was performed in the same manner as described above.

The results are shown in Table 1.

(Example 5)

The first filler (α-alumina, HIT-70) was 0.45 mass%, the second filler (boron nitride, HP-40) was 70.29 mass%, the thermosetting resin (resin C) was 10.34 mass%, and the hardener (CRN) ) 6.05 mass%, 0.11% by mass of a hardening accelerator (TPP), 0.07 mass% of a decane coupling agent (KBM-573), and 12.69 mass% of a solvent (CHN), and an epoxy is obtained in the form of a resin composition containing a solvent. Resin varnish.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 1.

(Example 6)

The first filler (α-alumina, HIT-70) was 0.45 mass%, the second filler (boron nitride, HP-40) was 70.29 mass%, the thermosetting resin (resin D) was 10.42% by mass, and the hardener (CRN) ) 5.90% by mass, hardening accelerator (TPP) 0.11% by mass, decane coupling agent (KBM-573) 0.07 mass%, and solvent (CHN) 12.76 mass % is mixed, and an epoxy resin varnish is obtained in the form of a resin composition containing a solvent.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 1.

(Example 7)

The first filler (α-alumina, HIT-70) was 0.45 mass%, the second filler (boron nitride, HP-40) was 74.23 mass%, the thermosetting resin (resin A) was 7.23 mass%, and the hardener (CRN) 4.46% by mass, a hardening accelerator (TPP) of 0.08% by mass, a decane coupling agent (KBM-573) of 0.07% by mass, and a solvent (CHN) of 13.48% by mass, and an epoxy obtained in the form of a resin composition containing a solvent. Resin varnish.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.27% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 81% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 1.

(Comparative Example 1)

70.61% by mass of the second filler (boron nitride, HP-40), 10.26% by mass of the thermosetting resin (resin A), 6.34% by mass of the curing agent (CRN), 0.11% by mass of the hardening accelerator (TPP), and decane coupling The agent (KBM-573) was mixed with 0.07 mass%, and the solvent (CHN) was 12.61 mass%, and the epoxy resin varnish was obtained in the form of a resin composition containing a solvent.

The density of the boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing the resin A and the CRN was set to 1.20 g/cm ³ , and the second filler was calculated relative to the second filler and the thermosetting resin. After the ratio of the total volume of the hardener, the result was 74% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 2.

(Comparative Example 2)

The first filler was replaced with a cerium oxide nano filler (manufactured by Admatechs, trade name: Admanano, average particle diameter: 15 nm), and the cerium oxide nano filler was 0.25 mass%, and the second filler (boron nitride, HP-40) 70.49% by mass, thermosetting resin (resin A) 10.22% by mass, hardener (CRN) 6.30 % by mass, 0.11% by mass of a hardening accelerator (TPP), 0.07 mass% of a decane coupling agent (KBM-573), and 12.56 mass% of a solvent (CHN), and an epoxy resin varnish is obtained in the form of a resin composition containing a solvent. .

The density of cerium oxide was set to 2.20 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ to calculate oxidation. The ratio of the nano-filler to the total volume of the ruthenium oxide filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 2.

(Comparative Example 3)

Α-alumina filler (manufactured by Sumitomo Chemical Co., Ltd., trade name: AA-07, average particle diameter: 700 nm) 0.72% by mass, second filler (boron nitride, HP-40) 66.82% by mass, thermosetting Resin (resin A) 12.65 mass%, hardener (CRN) 3.90 mass%, hardening accelerator (TPP) 0.13 mass%, decane coupling agent (KBM-573) 0.07 mass%, and solvent (CHN) 11.81 mass% mixed An epoxy resin varnish is obtained in the form of a resin composition containing a solvent.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.40% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 69% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 2.

(Comparative Example 4)

Γ-alumina nanofiller (manufactured by Daming Chemical Co., Ltd., trade name: TM-300D, average particle diameter: 10 nm), 0.45 mass%, second filler (boron nitride, HP-40), 70.29 mass%, Thermosetting resin (resin A) 10.22% by mass, curing agent (CRN) 6.30% by mass, curing accelerator (TPP) 0.11% by mass, decane coupling agent (KBM-573) 0.07% by mass, and solvent (CHN) 12.56 mass % is mixed, and an epoxy resin varnish is obtained in the form of a resin composition containing a solvent.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 2.

(Comparative Example 5)

0.45 mass% of the first filler (α-alumina, HIT-70), 70.29 mass% of the second filler (boron nitride, HP-40), and bisphenol A type epoxy resin (DIC (as thermosetting resin) Co., Ltd., trade name: EPICLON 850, no liquid crystal based) 10.08 mass%, hardener (CRN) 6.58 mass%, hardening accelerator (TPP) 0.11 mass%, decane coupling agent (KBM-573) 0.07 mass%, and The solvent (CHN) was mixed at 12.42% by mass, and the epoxy resin varnish was obtained in the form of a resin composition containing a solvent.

The density of alumina was set to 3.97 g/cm ³ , the density of boron nitride was set to 2.18 g/cm ³ , and the density of the mixture obtained by mixing resin A and CRN was set to 1.20 g/cm ³ . The ratio of a filler to the total volume of the first filler and the second filler and the thermosetting resin and the hardener was 0.26% by volume. Further, when the ratio of the second filler to the total volume was calculated, it was 74% by volume.

The same procedure as in Example 1 was carried out except that the epoxy resin varnish obtained above was used, and a B-stage sheet and a cured resin with a copper foil were prepared, and evaluated in the same manner as above.

The results are shown in Table 2.

Furthermore, in Tables 1 and 2, "-" means that it is not added.

The alumina particle-sized alumina filler is combined with a thermosetting resin having a liquid crystal group in the molecule, and the cured resin sheets of any of Examples 1 to 7 all exhibit high thermal conductivity. Further, in any of the examples 1 to 7, the thermal conductivity of the cured resin of the cured resin sheet is a thermal conductivity of the cured resin obtained from the cured resin without the filler. Higher value. This proves that the thermosetting resin having a liquid crystal group exhibits higher order with the alumina filler as the core and also improves the thermal conductivity of the cured resin itself. Further, in any of Examples 1 to 7, the flow amount and the dielectric breakdown voltage were good.

In Comparative Examples 1, 2, and 4 in which the alumina filler having no nanoparticle size was added as compared with Example 1, the thermal conductivity of the cured resin sheet was low, and the heat conductivity of the cured resin was converted from the cured resin sheet. The rate is lower than the thermal conductivity of the cured resin obtained from the hardened resin without filler. Further, in Comparative Example 5, an epoxy resin which does not have a liquid crystal base was used, and in Comparative Example 5, the thermal conductivity of the cured resin was lower than that of Example 1. Further, the alumina filler as the first filler of Comparative Example 3 had a particle diameter of 1 nm or more and less than 500 nm, and the flow amount was remarkably lowered.

The disclosure of International Patent Application No. PCT/JP2011/075345 and Japanese Patent Application No. 2012-090473 is hereby incorporated by reference in its entirety herein. All documents, patent applications, and technical specifications described in the specification are used in the specification, and are specifically described herein as the same as the individual descriptions.

Claims (21)

A resin composition comprising: a first filler having a peak in a range of 1 nm or more and less than 500 nm in a particle size distribution measured by a laser diffraction method, and containing α-alumina The second filler having a peak in a particle size distribution measured by a laser diffraction method in a range of 1 μm to 100 μm, and a thermosetting resin having a liquid crystal group in the molecule. A resin composition comprising: a first filler having an average particle diameter (D50) corresponding to a cumulative 50% of a weight cumulative particle size distribution from a small particle diameter side of 1 nm or more and less than 500 nm, and containing α - an alumina; a second filler having an average particle diameter (D50) corresponding to a cumulative 50% of the cumulative particle size distribution from the small particle diameter side of from 1 μm to 100 μm; and a thermosetting resin having intramolecular Liquid crystal based. The resin composition according to claim 1 or 2, wherein the content of the first filler is from 0.1% by volume to 10% by volume based on the total volume. The resin composition according to any one of claims 1 to 3, wherein the second filler contains a nitride filler. The resin composition according to claim 4, wherein the nitride filler contains at least one selected from the group consisting of boron nitride and aluminum nitride. The resin composition according to any one of claims 1 to 5, wherein the content of the second filler is 55 to 85% by volume in the total volume. The resin composition according to any one of claims 1 to 6, wherein the thermosetting resin is an epoxy resin. The resin composition according to any one of claims 1 to 7, wherein the liquid crystal group has a structure in which three or more six member ring groups are connected in a straight chain. The resin composition according to claim 7, wherein the epoxy resin is as shown in the following formula (III) or (IV): [In the general formula (III), Ar ¹ , Ar ² and Ar ³ are the same or different and each represents a divalent group represented by any one of the following formulas; R ¹ , R ² , R ³ , R ⁴ and R ^{5 ;} And R ⁶ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms; and Q ¹ and Q ² are the same or different, each represents a linear alkyl group having 1 to 9 carbon atoms, and constitutes the linear chain. The methylene group of the alkyl group may be substituted by an alkylene group having 1 to 18 carbon atoms, and -O- or -N(R ⁷ )- may be inserted between the methylene groups; here, R ⁷ Represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms] [wherein R represents independently a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, a represents an integer of 1 to 8, b, e and g represent an integer of 1 to 6, and c represents an integer of 1 to 7, d And h represents an integer of 1 to 4, and f represents an integer of 1 to 5. Further, when R is a plural number in the above divalent group, all Rs may represent the same group, and may represent different groups. In the formula (IV), R ¹ to R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. The resin composition according to any one of claims 1 to 9, which further comprises a phenol novolak resin. The resin composition according to claim 10, wherein the phenol novolak resin contains at least one selected from the group consisting of the following general formulae (I-1) and (I-2) Compounds of the structural units shown: In the general formulae (I-1) and (I-2), R ¹ each independently 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 each independently represents an integer of 0 to 2, and n each independently represents an integer of 1 to 7. The resin composition according to claim 10 or 11, wherein the phenolic novolac resin contains a monomer having a phenolic compound constituting the phenolic novolak resin in a ratio of 5 mass% to 80 mass%. %. A semi-hardened resin composition which is a semi-hardened body of the resin composition according to any one of the above claims 1 to 12. A hardened resin composition which is a hardened body of the resin composition according to any one of claims 1 to 12. A sheet-like formed body of the resin composition according to any one of claims 1 to 12, which is a resin sheet. The resin sheet according to claim 15 has a flow amount in a semi-hardened state of 130% to 210%. A prepreg having a fibrous base material, and the resin composition according to any one of claims 1 to 12, which is impregnated into the fibrous base material. A laminated board having an adhesive material, a semi-hardened resin composition layer or a hardened resin composition layer, the semi-hardened resin composition layer or the hardened resin composition layer being disposed on the above-mentioned adhered material, the semi-hardened The resin composition layer is a group consisting of the resin composition according to any one of claims 1 to 12, the resin sheet according to claim 15 or 16, and the prepreg described in claim 17. A semi-hardened body of at least one selected from the group consisting of the resin composition according to any one of claims 1 to 12, the resin sheet according to claim 15 or 16, and the request item 17 At least one hardened body selected from the group consisting of the prepregs. A metal substrate which is sequentially laminated with a metal foil, a hardened resin composition layer, and a metal plate, the hardened resin composition layer being the resin composition according to any one of claims 1 to 12, the request item 15 or A resin sheet according to 16 or a hardened body selected from at least one of the prepregs described in claim 17. A printed wiring board which is sequentially laminated with a metal plate, a hardened resin composition layer, and a wiring layer, the hardened resin composition layer being the resin composition according to any one of claims 1 to 12, claim 15 Or a resin sheet according to item 16 or at least one selected from the group consisting of the prepregs according to claim 17. A power semiconductor device comprising: a semiconductor module in which a metal plate, a solder layer, and a semiconductor wafer are sequentially laminated; a heat dissipating member; and a hardened body of the resin sheet according to claim 15 or 16, which is disposed in the semiconductor Between the aforementioned metal plate of the module and the heat dissipating member.