JP2018021156A - Resin composition, and cured molding, adhesive sheet, and substrate comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition having high thermal conductivity, and a cured molding, an adhesive sheet, and a substrate comprising the resin composition.SOLUTION: A resin composition contains a thermosetting resin, an inorganic filler, and a resin fiber. Based on 100 pts.mass of all the resin components, a content of the inorganic filler is 300-1500 pts.mass and a content of the resin fiber is 0.1-20 pts.mass.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition, and a cured molded article, an adhesive sheet, and a substrate using the same.

  2. Description of the Related Art In recent years, the heat generation density inside an electronic device has been increasing year by year with the increase in the speed and integration of circuits of electric devices or electronic devices and the increase in the mounting density of heat-generating electronic components on printed wiring boards. Therefore, a member having high thermal conductivity and electrical insulation that efficiently dissipates heat generated in an electronic component or the like is required.

  In particular, in electronic equipment that mounts semiconductor power devices, insulation and high thermal conductivity materials that have higher heat dissipation than ever are required due to downsizing and increased heat generation density due to weight reduction and increase in capacity. It has been.

  In order to solve such a problem, a high thermal conductivity material using a composite material containing an inorganic filler is generally known. For example, a method has been proposed in which a thermally conductive filler such as aluminum oxide is dispersed and blended in a binder resin that serves as an insulating layer (see, for example, Patent Document 1 below).

  In addition, in order to obtain a film or sheet having insulating properties and excellent thermal conductivity, a method of introducing a thermosetting resin into a resin fiber capable of imparting thermal conductivity has been proposed (for example, the following) Patent Document 2).

JP 2004-10668 A JP 2014-214281 A

  However, in the method disclosed in Patent Document 1 described above, there is an upper limit on the amount of inorganic filler that can be filled into the resin. That is, there is a limit to improvement in thermal conductivity only by filling with an inorganic filler.

  In addition, in the method disclosed in Patent Document 2 described above, there are cases where resin fibers cannot be included until a sufficient thermal conductivity is obtained. That is, even if resin fibers are used, the thermal conductivity of the obtained film or sheet may be insufficient.

  In order to solve the above-described problems, the present invention provides a resin composition having high thermal conductivity, and a cured molded article, an adhesive sheet, and a substrate using the resin composition.

As a result of intensive studies on such problems, the present inventors have found that the resin composition containing the thermosetting resin (A), the inorganic filler (C), and the resin fiber (D), the inorganic filler (C) and It has been found that a resin composition having high thermal conductivity is obtained when the resin fiber (D) is prepared in a specific amount, and the present invention has been achieved.
That is, the present invention is as follows.

<1> A resin composition containing a thermosetting resin, an inorganic filler, and a resin fiber, wherein the content of the inorganic filler is 300 to 1500 parts by mass with respect to 100 parts by mass of all resin components. And the resin composition whose content of the said resin fiber is 0.1-20 mass parts.
<2> The resin composition according to <1>, wherein a fiber length of the resin fiber is 0.01 mm to 20 mm.
<3> The resin composition according to <1> or <2>, wherein the resin fiber is a crystalline thermoplastic resin fiber.
<4> The resin composition according to any one of <1> to <3>, wherein the thermal conductivity in the fiber length direction of the resin fiber is 10 W / mK or more.
<5> The resin composition according to any one of <1> to <4>, wherein the resin fiber is a polybenzoxazole resin fiber.
<6> The thermosetting resin according to any one of <1> to <5>, wherein the thermosetting resin is at least one selected from the group consisting of an epoxy resin, a bismaleimide resin, a cyanate resin, and a phenol resin. Resin composition.
<7> The resin composition according to any one of <1> to <6>, wherein the inorganic filler has a thermal conductivity of 10 W / mK or more.
<8> Any one of <1> to <7>, wherein the inorganic filler is one or more selected from the group consisting of aluminum oxide, aluminum nitride, boron nitride, zinc oxide, magnesium oxide, and beryllium oxide. The resin composition as described in one.
<9> The resin composition according to any one of <1> to <8>, further including a curing agent.
<10> The resin composition according to any one of <1> to <9>, further including an organic solvent.
<11> A cured molded product obtained by curing the resin composition according to any one of <1> to <10>.
<12> An adhesive sheet in a B-stage state comprising the resin composition according to any one of <1> to <10>.
<13> A substrate obtained by curing the adhesive sheet according to <12>.

  According to the present invention, it is possible to provide a resin composition having high thermal conductivity, and a cured molded article, an adhesive sheet, and a substrate using the resin composition.

  Hereinafter, the present invention will be described in detail using embodiments. In addition, the following embodiment is an illustration for demonstrating this invention, and this invention is not limited only to the embodiment.

<Resin composition>
The resin composition of the present embodiment is a resin composition containing a thermosetting resin (A), an inorganic filler (C), and a resin fiber (D), and 100 parts by mass of all resin components. On the other hand, content of the said inorganic filler (C) is 300-1500 mass parts, and content of the said resin fiber (D) is 0.1-20 mass parts. Moreover, the resin composition of this embodiment may use a hardening | curing agent (B) as needed according to the kind of thermosetting resin (A). Here, “all resin constituent components” means the total amount of the thermosetting resin (A) and the curing agent (B) contained in the resin composition. That is, when the curing agent (B) is not used in the resin composition, the total amount of the thermosetting resin (A) is obtained. In the resin composition of the present embodiment, by setting the contents of the inorganic filler (C) and the resin fiber (D) in the above range, either the inorganic filler (C) or the resin fiber (D) is used alone. Excellent thermal conductivity can be exhibited compared to the case of using. In addition, the resin composition of the present embodiment has excellent heat as compared with a composition in which each content is out of the above category even when the inorganic filler (C) and the resin fiber (D) are used in combination. Conductivity can be demonstrated.

  The resin composition of the present embodiment can be cured to form a cured molded product. When the resin composition of the present embodiment is cured, it is difficult to form an air layer (bubbles). Since the air layer in the cured molded product causes a decrease in thermal conductivity, the resin composition in the present embodiment is presumed to be excellent in thermal conductivity from this viewpoint. Furthermore, since the resin composition of this embodiment hardly forms bubbles in the composition, voids are hardly generated on the surface of the cured molded article, and the moldability after curing molding is excellent.

<Thermosetting resin (A)>
The thermosetting resin (A) used in the present embodiment contains an inorganic filler (C) and a resin fiber (D), and undergoes a polymerization reaction (with a curing agent (B) as necessary) by heating to form a cured product. Any resin that can be molded can be used without particular limitation. The thermosetting resin (A) is not particularly limited, and examples thereof include an epoxy resin, a bismaleimide resin, a cyanate resin, and a phenol resin from the viewpoint of impact resistance of the obtained molded product. These may be used alone or in combination of two or more.

  As an epoxy resin, if it is an epoxy resin which has two or more epoxy groups in 1 molecule, a well-known thing can be used suitably, The kind is not specifically limited. Specifically, bisphenol A type epoxy resin, bisphenol E type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, bisphenol A novolac type epoxy resin, glycidyl ester type epoxy resin, aralkyl novolak Type epoxy resin, biphenyl aralkyl type epoxy resin, naphthylene ether type epoxy resin, cresol novolac type epoxy resin, polyfunctional phenol type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, naphthalene skeleton modified novolak type epoxy resin, phenol aralkyl Type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, alicyclic ester Carboxy resin, a polyol type epoxy resins, phosphorus-containing epoxy resin, glycidyl amine, glycidyl ester, compounds of the double bonds epoxidized in butadiene, such as a compound obtained by reaction of a hydroxyl-group-containing silicon resin with epichlorohydrin. Among these epoxy resins, those having a low melting point are preferable in terms of moldability at the time of curing molding, and bisphenol A type epoxy resins that are liquid at room temperature are particularly preferable. These epoxy resins can be used alone or in combination of two or more.

  The bismaleimide resin is a resin obtained by polymerizing a bismaleimide compound. Examples of the bismaleimide compound include 1,1 ′-(methylenedi-4,1-phenylene) bismaleimide, N, N′-m-phenylenebismaleimide, and 2,2′-bis- [4- (4-maleimidephenoxy). ) Phenyl] propane, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 4,4′-diphenyl ether bismaleimide, 4 , 4′-diphenylsulfone bismaleimide, 1,3-bis (3-maleimidophenoxy) benzene, 1,3-bis (4-maleimidophenoxy) benzene, N, N′-4,4′-diphenyl ether bismaleimide, N , N′-4,4-dicyclohexylmethane bismaleimide, N, N′-ethylene bismaleimide, N N′-butylene bismaleimide, N, N′-hexamethylene bismaleimide, N, N′-diphenylcyclohexane bismaleimide, 1,6-bismaleimide- (2,2,4-trimethyl) hexane, 1,6-bis Maleimidohexane, 1,11-bismaleimide diethylene glycol, 1,4-bis (4-maleimidophenoxy) ethane, 1,4-bis (4-maleimidophenoxy) propane, 1,4-bis (4-maleimidophenoxy) butane, 1,4-bis (4-maleimidophenoxy) hexane, bis (4-maleimidophenyl) methylamine, bis (4-maleimidophenyl) phenylamine, N, N′-4,4′-diphenylsulfone bismaleimide, N, N'-4,4'-diphenyl sulfide bismaleimide, etc. That, without being limited thereto. The bismaleimide resins synthesized from these bismaleimide compounds can be used alone or in combination of two or more.

  As cyanate resin, a well-known thing can be used suitably, The kind is not specifically limited. Specifically, naphthol aralkyl type cyanate resin, phenol novolak type cyanate resin, cresol novolak type cyanate resin, and phenol aralkyl type cyanate resin can be mentioned. These cyanate resins can be used alone or in combination of two or more.

  As the phenol resin, a generally known resin can be used as long as it is a phenol resin having two or more hydroxyl groups in one molecule. For example, bisphenol A type phenol resin, bisphenol E type phenol resin, bisphenol F type phenol resin, bisphenol S type phenol resin, phenol novolac resin, bisphenol A novolac type phenol resin, glycidyl ester type phenol resin, aralkyl novolac type phenol resin, biphenyl Aralkyl type phenolic resin, cresol novolac type phenolic resin, polyfunctional phenolic resin, naphthol resin, naphthol novolak resin, polyfunctional naphthol resin, anthracene type phenolic resin, naphthalene skeleton modified novolak type phenolic resin, phenolaralkyl type phenolic resin, naphthol aralkyl type Phenol resin, dicyclopentadiene type phenol resin, biphenyl type phenol resin Alicyclic phenolic resins, polyol-type phenolic resin, a phosphorus-containing phenol resin, a polymerizable unsaturated hydrocarbon of the group containing phenolic resin and hydroxyl-containing silicone resins and the like, but is not particularly limited. Among these phenol resins, biphenyl aralkyl type phenol resins, naphthol aralkyl type phenol resins, phosphorus-containing phenol resins, and hydroxyl group-containing silicone resins are preferable in terms of flame retardancy. These phenol resins can be used individually by 1 type or in combination of 2 or more types.

  As described above, the thermosetting resin (A) is preferably at least one selected from the group consisting of epoxy resins, bismaleimide resins, cyanate resins, and phenol resins. Furthermore, bisphenol A type liquid epoxy resin is more preferable from the viewpoint of flowability, price, strength, and the like.

<Curing agent (B)>
The resin composition of this embodiment can use a hardening | curing agent (B) as needed. For example, when an epoxy resin or the like is used as the thermosetting resin (A), the crosslinking reaction of the thermosetting resin (A) can be started and promoted by using the curing agent (B). The curing agent (B) is not particularly limited as long as it can react with the thermosetting resin (A) and can cure the thermosetting resin (A) by a crosslinking reaction or the like, but is not limited to epoxy resin, bismaleimide resin, cyanate. A curing agent applicable to each of the resin and the phenol resin is preferable. As such a curing agent, for example, a phenol compound, an acid anhydride compound, an amine compound, an allyl compound, a propenyl compound, and the like are preferable. ), An amine curing agent (ST12, manufactured by Mitsubishi Chemical Corporation), and the like.

-Content of thermosetting resin (A) and curing agent (B)-
The respective contents of the thermosetting resin (A) and the curing agent (B) in the resin composition can be appropriately set according to the type and application. On the other hand, the total amount of the thermosetting resin (A) and the curing agent (B) in the resin composition (including the case where the curing agent (B) is not used) is not particularly limited, but has a high thermal conductivity. From the viewpoint, the total solid content in the composition (that is, the total amount of the thermosetting resin (A), the curing agent (B), the inorganic filler (C), and the resin fiber (D)) is 6 to 24.9. % By mass is preferable, 6 to 23% by mass is more preferable, and 6 to 22.5% by mass is particularly preferable.

Moreover, the resin composition of this embodiment may contain a hardening accelerator in order to adjust the hardening rate of a thermosetting resin (A) suitably as needed. As said hardening accelerator, what is generally used as hardening accelerators, such as an epoxy resin and cyanate resin, can be used suitably, The kind is not specifically limited.
Specific examples of the curing accelerator include zinc octylate, zinc naphthenate, cobalt naphthenate, copper naphthenate, iron acetylacetone, nickel octylate, manganese octylate, phenol, xylenol, cresol, resorcin, and catechol. Phenol compounds such as octylphenol and nonylphenol, alcohols such as 1-butanol and 2-ethylhexanol, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, Imidazoles such as 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and Derivatives of imidazoles such as carboxylic acids or their anhydrides, dicyandiamide, benzyldimethylamine, amines such as 4-methyl-N, N-dimethylbenzylamine, phosphine compounds, phosphine oxide compounds, Phosphorium salt compounds, phosphorus compounds such as diphosphine compounds, epoxy-imidazole adduct compounds, benzoyl peroxide, p-chlorobenzoyl peroxide, di-t-butyl peroxide, diisopropyl peroxycarbonate, di-2-ethylhexyl Examples thereof include peroxides such as peroxycarbonate, and azo compounds such as azobisisobutyronitrile. A hardening accelerator can be used individually by 1 type or in combination of 2 or more types.
The amount of the curing accelerator used can be appropriately adjusted in consideration of the degree of curing of the resin, the viscosity of the resin composition, and the like, and is not particularly limited, but is usually 0 when all resin components are 100 parts by mass. It is preferably 0.001 to 10 parts by mass.

<Inorganic filler (C)>
The resin composition of this embodiment contains an inorganic filler (C). The inorganic filler (C) contributes to the improvement of the thermal conductivity of the resin composition and is used as a filler. In this embodiment, content of the inorganic filler (C) in a resin composition is 300-1500 mass parts with respect to 100 mass parts of all the resin structural components, Preferably it is 350-1400 mass parts. When the content of the inorganic filler (C) is less than 300 parts by mass, sufficient thermal conductivity may not be obtained in the resin composition. Moreover, when there is more content of an inorganic filler (C) than 1500 mass parts, an air layer (what is called a void (bubble)) is included in a hardening molding by lack of a resin component, and thermal conductivity may fall. Moreover, when the resin component in a resin composition is insufficient, the moldability of a resin composition may fall.

  An inorganic filler (C) is not specifically limited, A well-known thing can be used suitably. For example, the inorganic filler (C) is preferably at least one selected from the group consisting of aluminum oxide, aluminum nitride, boron nitride, zinc oxide, magnesium oxide, and beryllium oxide from the viewpoint of thermal conductivity. These inorganic fillers (C) can be used singly or in appropriate combination of two or more.

  The thermal conductivity of the inorganic filler (C) is preferably 10 W / mK or more from the viewpoint of thermal conductivity, more preferably 12 W / mK or more, and particularly preferably 15 W / mK or more.

  The shape of the inorganic filler (C) is not particularly limited, and is not particularly limited such as a particle shape, a powder shape, a fiber shape, a scale shape, a whisker shape, and a needle shape. Also, the size of the inorganic filler is not particularly limited. For example, from the viewpoint of uniform dispersion of the composition, the average particle size of the particulate inorganic filler (C) is preferably 100 μm to 100 mm, and 150 μm to 80 mm. Is more preferable, and 200 μm to 70 mm is particularly preferable.

  In using the inorganic filler (C), a silane coupling agent may be used in combination. As the silane coupling agent, those generally used for inorganic surface treatment can be suitably used, and the type thereof is not particularly limited. Specifically, aminosilanes such as γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxylane, γ-glycidoxypropyltrimethoxysilane, β- (3,4) -Epoxycyclohexyl) Epoxysilane such as ethyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinylsilane such as vinyl-tri (β-methoxyethoxy) silane, N-β- (N-vinylbenzylaminoethyl)- Cationic silanes such as γ-aminopropyltrimethoxysilane hydrochloride, phenylsilanes and the like can be mentioned. A silane coupling agent can be used individually by 1 type or in combination of 2 or more types. Although content of a silane coupling agent is not specifically limited, From a viewpoint of improving the dispersibility with respect to resin, 0.1-10 mass% is preferable with respect to the total amount of an inorganic filler (C), 0 3 to 5% by mass is more preferable, and 0.5 to 3% by mass is particularly preferable.

<Resin fiber (D)>
The resin composition of this embodiment contains a resin fiber (D). The resin fiber (D) contributes to the improvement of the thermal conductivity of the resin composition and is used as a filler. In addition, it is not clear why the resin composition (D) and the inorganic filler (C) are used in combination, and the content of these resins is within a predetermined range, thereby improving the thermal conductivity of the resin composition. It is presumed that the thermal conductivity of the entire resin composition is improved by thermally connecting the resin fibers (D) between C). Moreover, as resin fiber (D), it is preferable to have insulation.

  In the present embodiment, the content of the resin fiber (D) is 0.1 to 20 parts by mass, preferably 1 to 20 parts by mass with respect to 100 parts by mass of all resin constituents, and easy to handle. From a viewpoint, 5-10 mass parts is still more preferable. Resin satisfying the space between the inorganic filler (C) and the resin fiber (D) when the content of the resin fiber (D) is larger than 20 parts by mass with respect to 100 parts by mass of all resin constituent components Insufficient components may include an air layer in the cured molded product, which may reduce thermal conductivity. Moreover, this may also reduce the moldability of the cured molded product. When the amount of the resin fiber (D) is less than 0.1 parts by mass with respect to 100 parts by mass of the total resin components, desired thermal conductivity may not be maintained.

  The fiber length of the resin fiber (D) is preferably 0.01 mm to 20 mm, and more preferably 0.1 mm to 1.0 mm. When the fiber length of the resin fiber (D) is in the above range, it is easy to disperse in the resin composition by kneading or stirring.

  The resin fiber (D) is not particularly limited as long as it is fibrous, but is preferably a crystalline thermoplastic resin from the viewpoint of thermal conductivity. Here, the “crystalline thermoplastic resin” means a resin having crystals in which molecular chains are regularly arranged and exhibiting plasticity when heated. Specific examples of the crystalline thermoplastic resin include, but are not limited to, polyolefin resin, polyester resin, polyacetal resin, polyphenylene sulfide resin, polyamide resin, liquid crystal polymer, and the like. Among these, polyamide resins are preferable, specifically, polybenzazole resin fibers and polybenzoxazole resin fibers (PBO fibers) are preferable, and polybenzoxazole resin fibers are particularly preferable.

  The resin fiber (D) preferably has a thermal conductivity in the fiber length direction of 10 W / mK or more, more preferably 20 W / mK or more, and more preferably 30 W / mK or more from the viewpoint of thermal conductivity. Is particularly preferred. For example, polybenzoxazole resin fibers have high thermal conductivity and are preferable from the viewpoint of distribution.

  The resin composition of this embodiment can be prepared according to a conventional method, and the resin composition in which the thermosetting resin (A), the curing agent (B), the inorganic filler (C), and the resin fiber (D) are uniformly dispersed. If it is a method by which a thing is obtained, the preparation method will not be specifically limited. For example, it can be appropriately carried out using a known device such as a revolving / spinning type mixing device, a heating roll, and a kneader.

  Moreover, the mass ratio (C: D) of the inorganic filler (C) and the resin fiber (D) contained in the resin composition of the present embodiment is 15000: 1 to 15 from the viewpoint of thermal conductivity and moldability. : 1 is preferable, 1500: 1 to 20: 1 is more preferable, and 500: 1 to 30: 1 is particularly preferable.

<< Resin composition containing organic solvent (varnish) >>
As a method other than the above-mentioned preparation method, components constituting the composition can be dissolved or dispersed in a solvent (for example, an organic solvent) and used as a varnish (hereinafter, a resin composition containing a solvent is simply referred to as “varnish”. Sometimes called). A resin composition using an organic solvent can obtain a resin composition in which each component is uniformly dispersed by removing the organic solvent after coating or the like.

  Any known organic solvent can be used as long as it dissolves or is compatible with at least a part, preferably all of the components of the various resin compositions described above, and the type thereof is particularly limited. It is not something. Specifically, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; cellosolv solvents such as propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate; ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, isoamyl acetate, ethyl lactate And ester solvents such as methyl methoxypropionate and methyl hydroxyisobutyrate; polar solvents such as amides such as dimethylacetamide and dimethylformamide; and nonpolar solvents such as aromatic hydrocarbons such as toluene and xylene. These can be used alone or in combination of two or more.

  As described above, after the thermosetting resin (A), the curing agent (B), the inorganic filler (C), and the resin fiber (D) are uniformly dispersed, the resin composition is cured and molded. The curing molding method is not particularly limited, and known methods such as potting, transfer molding, injection molding, and compression molding can be appropriately used.

<< B-stage state adhesive sheet and substrate cured thereof >>
For example, an adhesive sheet can be formed using the above-mentioned resin composition. For example, the above-mentioned varnish (resin composition containing an organic solvent) is applied on a substrate such as a resin film or copper foil by coating or the like, and dried as necessary to obtain a semi-cured state, that is, an adhesive sheet in a B-stage state Can be obtained. The resin composition is preferably applied so that the film thickness on the substrate is 50 μm to 400 μm. As described above, in this specification, the “B stage state” refers to a semi-cured state in which a solvent is volatilized and dried and heated. By curing the adhesive sheet in the B-stage state, a substrate having excellent thermal conductivity can be manufactured.

  The method for applying the varnish is not particularly limited as long as the sheet-shaped resin composition having the above-described film thickness can be obtained. For example, the varnish is applied by a method such as a dip method, a spin coating method, a spray coating method, or a blade method. A coating film can be formed. For coating the varnish, a coating film having a predetermined film thickness can be uniformly formed on the substrate by using a coating apparatus such as a spin coater, a slit coater, a die coater, or a blade coater.

  In the drying process for removing the organic solvent, if the heating temperature is too low, the organic solvent in the coating film cannot be sufficiently removed, and the organic solvent remains in the obtained dry film, and the remaining organic solvent is not cured during the molding process. In some cases, the residual solvent evaporates, resulting in voids, and high thermal conductivity may decrease. On the other hand, if the heating temperature for drying is too high, the curing of the resin proceeds, and it may not be possible to obtain a good semi-cured film. Therefore, the heating conditions at the time of drying differ depending on the film thickness of the applied resin composition, the boiling point of the organic solvent in the coating liquid, and the type of the thermosetting resin (A) used. In the case of a film thickness of 50 to 400 μm, it is desirable to obtain a B-staged adhesive sheet by drying at 40 to 150 ° C., preferably 60 to 120 ° C., until the solvent is completely removed.

  The B-staged adhesive sheet formed by the above-described method can produce a molded substrate by heating to a temperature within the range of 150 ° C. to 250 ° C. and curing. A molding method for performing heating and pressing using a press machine is preferable for producing a smooth substrate. The board | substrate which used such a resin composition as the contact bonding layer can be used as the heat dissipation board | substrate mounted by an electronic device etc.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to these.

  Hereinafter, each component used in the Examples and Comparative Examples will be described.

<Thermosetting resin (A)>
・ DIC-850s (Bisphenol A type liquid epoxy resin, manufactured by DIC Corporation)
・ JER828 (Bisphenol A type liquid epoxy resin, manufactured by Mitsubishi Chemical Corporation)

<Curing agent (B)>
DL-92 (phenol novolac curing agent, manufactured by Meiwa Kasei Co., Ltd.)
・ ST12 (Amine curing agent, manufactured by Mitsubishi Chemical Corporation)

<Inorganic filler (C)>
FAN-f50 (aluminum nitride particles, average particle size: 50 μm, manufactured by Furukawa Electronics Co., Ltd.)
AA-18 (alumina particles, average particle size: 18 μm, manufactured by Sumitomo Chemical Co., Ltd.)
AA-3 (alumina particles, average particle size: 3 μm, manufactured by Sumitomo Chemical Co., Ltd.)
AA-03 (alumina particles, average particle size: 0.3 μm, manufactured by Sumitomo Chemical Co., Ltd.)
・ AZ35-75 (alumina particles, average particle size: 35 μm, manufactured by Nippon Steel & Sumikin Materials Co., Ltd.)
AZ10-75 (alumina particles, average particle size: 10 μm, manufactured by Nippon Steel & Sumikin Materials Co., Ltd.)
PT110 (scale-type boron nitride particles, average particle size: 45 μm, manufactured by Momentive Performance Materials Japan GK)

<Resin fiber (D)>
・ Zylon HM (polybenzoxazole resin fiber, fiber length 1 mm, fiber diameter: 12 μm, manufactured by Toyobo Co., Ltd.)

<Curing accelerator>
2PZ: 2-phenylimidazole

<Silane coupling agent>
・ KBM-403 (3-glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.)

  The blending was carried out using the raw materials described above. As for the compounding ratio of the thermosetting resin (A) and the curing agent (B), the functional group of the thermosetting resin (A) / the curing agent (B) was 1.0 in an equivalent ratio.

  The composition of each example and comparative example is as shown in the table below for thermosetting resin (A), curing agent (B), inorganic filler (C), resin fiber (D), curing accelerator, and silane coupling agent. Then, an organic solvent (methyl ethyl ketone) was added, and each component was dissolved or dispersed by stirring at room temperature to prepare a resin composition (varnish). Moreover, since methyl ethyl ketone is used as a solvent in all the examples in the following table, the description is omitted in each table.

  The obtained resin composition (varnish) was applied onto a polyethylene terephthalate (PET) film having a thickness of 50 μm whose surface was release-treated so that the resin thickness after drying was 200 to 300 μm. Next, the coating film was dried at 120 ° C. for 10 minutes to obtain a resin composition in which each component was uniformly dispersed. The obtained resin composition is in a semi-cured state and corresponds to an adhesive sheet in a B stage state. Furthermore, each test piece was obtained by filling this resin composition into a 1 mm-thick press die and performing a curing treatment at 200 ° C. for 30 minutes under a pressure of 10 MPa with a vacuum press.

<Measurement of thermal conductivity>
The thermal conductivity of the obtained test piece was measured. The thermal conductivity was measured with a test piece of 10 mm × 10 mm size by a laser flash method using a xenon flash analyzer LFA447 type thermal conductivity meter manufactured by NETZSCH.
<Moldability>
About the obtained test piece (10 mm x 10 mm size), the surface of the test piece was observed visually and the moldability was evaluated according to the following criteria.
(Standard)
A: No void (bubble) was observed on the surface of the test piece.
B: Although several voids (bubbles) were generated on the surface of the test piece, it was in a range where there was no problem.
C: Generation | occurrence | production of the void (bubble) was recognized notably on the surface of the test piece.

As is apparent from the above tables, the content of the inorganic filler (C) relative to the total resin components (total amount of the thermosetting resin (A) and the curing agent (B)) and The resin composition of the Example which filled the resin component combining the content of the resin fiber (D) within the scope of the present invention is a resin composition filled with only an inorganic filler and a resin composition containing a large amount of fibrous filler. It was confirmed that heat conduction performance superior to that can be exhibited. On the other hand, from the comparison between Example 1 and Comparative Example 7, even when the inorganic filler and the resin fiber are used in combination, when the content of the inorganic filler is small, compared to the example using the same kind of inorganic filler. It can be seen that the thermal conductivity is low. Moreover, even if it is a case where an inorganic filler and resin fiber are used together from the comparison with Example 4 and Comparative Example 9, when there is too much content of an inorganic filler, it is compared with the Example which uses the same kind of inorganic filler. It can be seen that the thermal conductivity is low. In Comparative Example 9, voids (bubbles) were generated in the cured film, and the moldability was poor. Furthermore, from the comparison between Example 1 and Comparative Example 8, even when the inorganic filler and the resin fiber are used in combination, when the content of the resin fiber is too much, it is compared with the example using the same kind of inorganic filler. It can be seen that the thermal conductivity is low.
Moreover, even if it is a composition using the same material about a filler, resin fiber, etc. from the comparison with Example 6 and the comparative example 10, and the comparison with Example 7 and Comparative Example 8, content of resin fiber (D) It can be seen that the thermal conductivity decreases when the content is less than 0.1% by mass or exceeds 20% by mass.

  As described above, the highly thermally conductive resin composition of the present invention can be applied to various fields, and for example, can be preferably applied to the formation of a heat-dissipating insulating layer or an adhesive layer in circuit boards, electronic devices, and the like.

Claims (13)

A resin composition containing a thermosetting resin, an inorganic filler, and a resin fiber,
The resin composition whose content of the said inorganic filler is 300-1500 mass parts with respect to 100 mass parts of all the resin structural components, and whose content of the said resin fiber is 0.1-20 mass parts.   The resin composition of Claim 1 whose fiber length of the said resin fiber is 0.01 mm-20 mm.   The resin composition according to claim 1, wherein the resin fiber is a crystalline thermoplastic resin fiber.   The resin composition as described in any one of Claims 1-3 whose heat conductivity in the fiber length direction of the said resin fiber is 10 W / mK or more.   The resin composition according to any one of claims 1 to 4, wherein the resin fiber is a polybenzoxazole resin fiber.   The resin composition according to any one of claims 1 to 5, wherein the thermosetting resin is one or more selected from the group consisting of an epoxy resin, a bismaleimide resin, a cyanate resin, and a phenol resin.   The resin composition as described in any one of Claims 1-6 whose thermal conductivity of the said inorganic filler is 10 W / mK or more.   The resin according to any one of claims 1 to 7, wherein the inorganic filler is at least one selected from the group consisting of aluminum oxide, aluminum nitride, boron nitride, zinc oxide, magnesium oxide, and beryllium oxide. Composition.   Furthermore, the resin composition as described in any one of Claims 1-8 containing a hardening | curing agent.   Furthermore, the resin composition as described in any one of Claims 1-9 containing an organic solvent.   A cured molded product obtained by curing the resin composition according to any one of claims 1 to 10.   The adhesive sheet of a B-stage state containing the resin composition as described in any one of Claims 1-10.   A substrate obtained by curing the adhesive sheet according to claim 12.