JP7352173B2 - Compositions, cured products, multilayer sheets, heat dissipation parts, and electronic parts - Google Patents

Description

The present invention relates to a composition, a cured product, a multilayer sheet, a heat dissipation component, and an electronic component. In particular, the composition of the present invention is suitable for use in electronic components such as semiconductor chips and heat dissipation bodies such as wiring boards, heat spreaders, and heat sinks. The present invention relates to a composition that can be used for adhesion or adhesion between electronic components.

In recent years, electronic devices have rapidly become denser. Adhesive compositions used in electronic devices often end up remaining inside the device as an adhesive, so they are required to satisfy various properties such as adhesiveness, heat dissipation, heat resistance, and insulation. .

Recently, GaN (gallium nitride) and SiC (silicon carbide), which have better electrical properties, have been attracting attention in place of the silicon (Si) wafers traditionally used as semiconductor devices, and are being used in fields such as power devices. It's progressing. In particular, since SiC has excellent electrical properties, the voltage applied to the unit area is higher than that of Si, and the temperature applied to the unit area is accordingly higher. Therefore, adhesives are required to have high heat resistance of 150°C, and in some cases over 200°C, and to efficiently dissipate heat to the outside, as well as long-term high-temperature resistance to maintain adhesiveness at that temperature for a long period of time. is required.

To date, adhesive sheets for semiconductor devices and dicing die bonding sheets containing thermoplastic resins such as acrylic copolymers and thermosetting resins such as epoxy resins have shown high moisture resistance reliability and high temperature cycleability. is disclosed. (For example, see Patent Documents 1 and 2). Furthermore, in order to maintain a constant temperature such as 150° C. in electronic device manufacturing equipment, there is a demand for a large size, for example, 300 mm square or more, and for bonding different materials such as a glass plate and a metal plate. In response to such demands, adhesive compositions for electronic devices having high temperature cycleability from -20° C. to 150° C. have been proposed (see Patent Document 3).

JP-A-11-265960 (Claim 1) JP2004-217793A (Claim 1) Japanese Patent Application Publication No. 2014-208782

However, the thermal conductivity of the adhesive compositions described in these Patent Documents 1 to 3 is as low as about 0.1 to 0.2 W/mK, and there is a problem in heat dissipation. As a method for improving heat dissipation, high thermal conductivity can be achieved by ultra-highly filling a thermally conductive filler, but by ultra-highly filling a filler that is more elastic than resin, the adhesive composition becomes highly elastic. , the temperature cyclability decreases.

The present invention solves the above-mentioned drawbacks and provides a composition, a cured product, a heat dissipating member, and an electronic component having high thermal conductivity and low elasticity.

In order to solve the above problems, the present invention has the following configuration.
<1> A composition comprising a resin or a resin precursor and a filler with a thermal conductivity of 1 W/mK or more,
The resin includes a polyimide resin,
The filler has an aspect ratio (average maximum length/average minimum length) of 1.0 to 1.9 (hereinafter, filler with an aspect ratio of 1.0 to 1.9 is referred to as (A ), and fillers with an aspect ratio of 2 or more and an average maximum length of 10.5 to 200.0 μm (hereinafter referred to as fillers with an aspect ratio of 2 or more and an average maximum length of 10.5 to 200 μm) 0 μm filler (denoted as (B)),
The volume ratio of (A) and (B) is (A):(B)=95:5 to 55:45, and the total volume ratio, which is the sum of the volume ratios of (A) and (B), is 15 % to 80% by volume.
<2>
The composition according to <1>, containing a silane coupling agent.
<3>
The filler is at least one member selected from the group consisting of alumina, silica, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, boehmite, graphite, graphene, carbon nanotubes, cellulose nanofibers, and carbon fibers. 1> or the composition described in <2>.
<4>
(A) is at least one selected from the group consisting of alumina, silica, aluminum nitride, zinc oxide, magnesium oxide, and boehmite,
The composition according to any one of <1> to <3>, wherein (B) is aluminum nitride.
<5>
The composition according to any one of <1> to <4>, wherein the average particle size D50 of (A) is 1.0 μm to 100.0 μm.
<6>
The composition according to any one of <1> to <5>, wherein the resin includes at least one selected from the group consisting of epoxy resin, phenol resin, urethane resin, silicone resin, acrylic resin, and polyamideimide resin. thing.
<7>
The polyimide resin is a polyimide resin containing 60 mol% or more of diamine residues having a structure represented by the following general formula (1) out of 100 mol% of the total diamine residues, <1> to <6>. The composition according to any one of the above.

(In the general formula (1), m represents an integer of 10 or more. R ⁵ and R ⁶ may be the same or different and represent an alkylene group or an arylene group having 1 to 30 carbon atoms. The arylene group is a substituent The substituent represents an alkyl group having 1 to 30 carbon atoms. R ¹ to R 4 may be the same or different, and each of R 1 to R ⁴ may have an alkyl group having 1 to 30 carbon atoms, a phenyl group, or a phenoxy group. (indicates the group)
<8>
The sheet-like composition according to any one of <1> to <7>, which has a sheet-like shape.
<9>
A cured product comprising the composition according to any one of <1> to <8>.
<10>
The cured product according to <9>, which has a thermal conductivity of 0.3 to 10 W/mK at 25°C and an elastic modulus of 0.01 to 100 MPa at -70°C.
<11>
The cured product according to <9> or <10>, which has a dielectric strength of 5 kV/mm or more.
<12>
A multilayer sheet comprising the composition according to <8> or the cured product according to any one of <9> to <11>, and an adhesive layer.
<13>
A heat dissipating component comprising the composition according to any one of <1> to <8>, the cured product according to any one of <9> to <11>, or the multilayer sheet according to <12>.
<14>
An electronic component comprising the composition according to any one of <1> to <8>, the cured product according to any one of <9> to <11>, or the multilayer sheet according to <12>.

The present invention can provide compositions, cured products, multilayer sheets, heat dissipation components, and electronic components that have low elasticity and high thermal conductivity.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the constituent elements (including elemental steps and the like) are not essential unless otherwise specified. The same applies to numerical values and their ranges, and they do not limit the present invention.

In this specification, the term "process" includes not only processes that are independent from other processes, but also processes that cannot be clearly distinguished from other processes, as long as the purpose of the process is achieved. It will be done.

In this specification, the numerical range indicated using "~" includes the numerical values written before and after "~" as the minimum value and maximum value, respectively.

In the numerical ranges described step by step in this specification, the upper limit value or lower limit value described in one numerical range may be replaced with the upper limit value or lower limit value of another numerical range described step by step. good. Further, in the numerical ranges described in this specification, the upper limit or lower limit of the numerical range may be replaced with the value shown in the Examples.

In this specification, if there are multiple types of substances corresponding to each component in the composition, unless otherwise specified, the content of each component in the composition refers to the total content of the multiple types of substances present in the composition. It means the content rate of

In this specification, the term "layer" includes cases where the layer is formed in the entire area when observing the area where the layer exists, as well as cases where the layer is formed only in a part of the area. Also included.

As used herein, the term "laminate" refers to stacking layers, and two or more layers may be bonded, or two or more layers may be removable.

<Composition>
The composition of the present invention is a composition containing a resin and a filler having a thermal conductivity of 1 W/mK or more, the resin containing a polyimide resin, and the filler having an aspect ratio (average maximum length). / average value of minimum length) is 1.0 to 1.9 (hereinafter, a filler with an aspect ratio of 1.0 to 1.9 will be referred to as (A)), and an aspect ratio of 2 or more, A filler with an average maximum length of 10.5 to 200.0 μm (hereinafter, a filler with an aspect ratio of 2 or more and an average maximum length of 10.5 to 200.0 μm is referred to as (B)). The volume ratio of (A) and (B) is (A):(B)=95:5 to 55:45, and the total volume ratio is the sum of the volume ratios of (A) and (B). , 15% to 80% by volume.

The composition of the present invention contains a combination of (A) and (B) as a filler having a thermal conductivity of 1 W/mK or more. By doing so, the thermal conductivity of the cured product made of the composition can be improved. From the viewpoint of the thermal conductivity of the composition, the thermal conductivity of the filler is preferably 10 W/mK or more, and more preferably 20 W/mK or more. If the composition contains only a filler with a thermal conductivity of less than 1 W/mK, it will be difficult to significantly improve thermal conductivity. The upper limit of the thermal conductivity of a filler having a thermal conductivity of 1 W/mK or more is not particularly limited as long as it is 1 W/mK or more, but a practical upper limit is about 5000 W/mK. Note that the composition of the present invention can also contain a filler with a thermal conductivity of less than 1 W/mK, as long as (A) and (B) are considered as fillers with a thermal conductivity of 1 W/mK or more.

As mentioned above, among fillers having a thermal conductivity of 1 W/mK or more, a filler having an aspect ratio of 1.0 to 1.9 is referred to as (A). The aspect ratio of (A) in the composition of the present invention is preferably 1.0 to 1.9 from the viewpoint of fluidity of the resin or resin precursor, and 1.0 to 1.5 is preferable for thermal conductivity. It is more preferable from the viewpoint of reducing anisotropy, and 1.0 to 1.2 is even more preferable from the viewpoint of filling property.

As mentioned above, a filler with a thermal conductivity of 1 W/mK or more, an aspect ratio of 2 or more, and an average maximum length of 10.5 to 200.0 μm is referred to as (B). The aspect ratio of (B) in the composition of the present invention is preferably 2 or more, more preferably 3 or more. From the viewpoint of heat conduction, 5 or more is more preferable. The average value of the maximum length is preferably 10.5 to 200.0 μm from the viewpoint of heat conduction, and more preferably 10.5 to 150.0 μm from the viewpoint of high filler filling property. 0 μm is more preferable from the viewpoint of filler sedimentation. If the aspect ratio of (B) is less than 2 or the average value of the maximum length is less than 10.5 μm, the effect of improving heat conduction is small. Moreover, if the average value of the maximum length of (B) is larger than 200 μm, it is necessary to increase the thickness of the composition, and it is difficult to lower the thermal resistance.

In the composition of the present invention, it is preferable that the volume ratio of (A) and (B) is (A):(B)=95:5 to 55:45 from the viewpoint of high thermal conductivity and low elasticity. The volume ratio of (A) and (B) in the composition of the present invention is more preferably (A):(B)=90:10 to 70:30.

In the composition of the present invention, the total volume fraction, which is the sum of the volume ratios of (A) and (B), is preferably from 15 volume % to 80 volume %, and from the viewpoint of thermal conductivity and fluidity, from 20 volume % to More preferably 70% by volume, and even more preferably 25% to 65% by volume. When the total volume fraction is less than 15% by volume, it is difficult to achieve high thermal conductivity, and when it is more than 80% by volume, the fluidity of the resin or resin precursor decreases, making it difficult to prepare the composition.

<Filler>
The composition of the present invention contains a filler having a thermal conductivity of 1 W/mK or more, and these fillers further include (A) having an aspect ratio of 1.0 to 1.9, and (A) having an aspect ratio of 2 or more, the maximum Contains (B) with an average length of 10.5 to 200.0 μm.

In the present invention, the aspect ratio means the average value of the maximum length/the average value of the minimum length. S4700), observe 50 particles and find the average value of the maximum length and the average value of the minimum length. From the obtained values, (average value of maximum length) ÷ (minimum length The aspect ratio is calculated from the average value of

Furthermore, the composition of the present invention may contain fillers other than (A) and (B). Other fillers refer to fillers that do not fall under either (A) or (B), and include, but are not limited to, inorganic fillers, organic fillers, conductive fillers, non-conductive fillers, etc., such as copper, aluminum, etc. , silver, diamond, alumina, silica, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, boehmite, graphite, graphene, carbon nanotubes, cellulose nanofibers, and carbon fibers. is preferred.

Examples of fillers with a thermal conductivity of 1 W/mK or more include inorganic components with a thermal conductivity of 1 W/mK or more, and the type thereof is not particularly limited, but the thermal conductivity is a value specific to the component. Therefore, fillers with a thermal conductivity of 1 W/mK or more include alumina, silica, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, boehmite, graphite, graphene, carbon nanotubes, cellulose nanofibers, and carbon fibers. It is preferable that at least one of the above is selected.

<Filler (A)>
The composition of (A) is not particularly limited, but is selected from the group consisting of alumina, silica, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, boehmite, graphite, graphene, carbon nanotubes, cellulose nanofibers, and carbon fibers. It is preferably at least one selected from the group consisting of alumina, silica, aluminum nitride, zinc oxide, magnesium oxide, and boehmite, and more preferably at least one selected from the group consisting of alumina, silica, aluminum nitride, zinc oxide, magnesium oxide and boehmite. From the viewpoint of thermal conductivity, at least one member selected from the group consisting of alumina, aluminum nitride, zinc oxide, and magnesium oxide is more preferable, and from the viewpoint of insulation, thermal conductivity, and stability, alumina and/or Most preferred is aluminum nitride.

In (A), one raw material filler may be used alone or two or more raw material fillers may be used in combination. (A) When using two or more raw material fillers together, when purchasing and using fillers, different product numbers with a thermal conductivity of 1 W/mK or more and an aspect ratio of 1.0 to 1.9 are used. This refers to the use of two or more fillers, and when the filler is manufactured and used, two or more different starting materials with a thermal conductivity of 1 W/mK or more and an aspect ratio of 1.0 to 1.9 are used. When using two or more fillers obtained by processing a substance under the same or different manufacturing conditions, or when using two or more fillers obtained by processing the same starting material under different manufacturing conditions. say. By using two or more raw material fillers as (A), for example, raw material fillers with different particle diameters D50 can be used as (A), or raw material fillers with different crystal shapes can be used as (A). Raw material fillers having different aspect ratios can be used as (A).

The average particle diameter D50 of (A) is not particularly limited, but is preferably 1.0 to 100.0 μm. From the viewpoint of resin fluidity, the average particle diameter D50 of (A) is more preferably 20 to 80 μm. If the average particle size D50 of (A) is less than 0.1 μm, the fluidity of the resin will decrease, and if it exceeds 100 μm, sedimentation of the filler may occur. The thickness is preferably 1.0 to 100.0 μm.

<Filler (B)>
The composition of (B) is not particularly limited, but is selected from the group consisting of alumina, silica, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, boehmite, graphite, graphene, carbon nanotubes, cellulose nanofibers, and carbon fibers. The thermal conductivity is preferably at least one selected from the group consisting of alumina, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, graphite, graphene, carbon nanotubes, and carbon fibers. It is more preferable from the viewpoint of thermal conductivity, and is even more preferable from the viewpoint of insulation, thermal conductivity, and stability. Therefore, aluminum nitride is particularly preferred.

The shape of (B) is not particularly limited, and examples include whisker-like needles, fibers, plates, and scales.

Specifically, examples of the needle-like material include aluminum nitride whiskers, and examples of the scale-like material include boron nitride and graphite. Examples of the fiber-like material include carbon fiber, and examples of the plate-like material include plate-like particles made of alumina.

In (B), one raw material filler may be used alone or two or more raw material fillers may be used in combination. (B) Using two or more raw material fillers together means that when fillers are purchased and used, the thermal conductivity is 1 W/mK or more, the aspect ratio is 2 or more, and the average value of the maximum length is 10.5. It refers to the use of two or more fillers of different product numbers with a diameter of ~200.0 μm. When manufacturing and using fillers, the fillers must have a thermal conductivity of 1 W/mK or more, an aspect ratio of 2 or more, and an average maximum length. When using two or more fillers obtained by processing two or more different starting materials with a value of 10.5 to 200.0 μm under the same or different manufacturing conditions, or when using the same starting material. This refers to the case where two or more fillers obtained by processing under different manufacturing conditions are used. By using two or more raw material fillers as (B), for example, raw material fillers with different particle diameters D50 can be used as (B), or raw material fillers with different crystal shapes can be used as (B). Raw material fillers having different aspect ratios can be used as (B).

<Resin>
The composition of the present invention includes a resin.

The composition of the present invention contains a polyimide resin as the resin.

The resin in the composition of the present invention is not particularly limited as long as it contains a polyimide resin, but at least one resin selected from the group consisting of an epoxy resin, a phenol resin, a urethane resin, a silicone resin, an acrylic resin, and a polyamide-imide resin. Preferably, it contains seeds.

It is also preferable that the composition of the present invention contains a resin precursor. The resin precursor is not particularly limited and may be a monomer, oligomer, or polymer, and at least one selected from the group consisting of epoxy resin, phenol resin, urethane resin, silicone resin, acrylic resin, polyimide resin, and polyamideimide resin. One resin precursor is preferred.

Although the composition of the present invention contains a polyimide resin as a resin, it is more preferable to contain a resin rather than a resin precursor as other components.From the viewpoint of low-temperature and low elasticity, resins other than polyimide resin include urethane resin, More preferably, it is selected from the group consisting of silicone resins and acrylic resins. Further, from the viewpoint of high adhesion, the resin other than polyimide resin is more preferably selected from the group consisting of epoxy resin and polyamideimide resin. From the viewpoint of low-temperature low elasticity and high adhesion, the resin other than polyimide resin is more preferably a resin system that is a combination of these resins, and more preferably a resin containing a polyimide resin and an epoxy resin.

Further, the polyimide resin contained as the resin is particularly preferably a polyimide resin containing 60 mol % or more of diamine residues having a structure represented by the following general formula (1) out of 100 mol % of the total diamine residues.

(In the general formula (1), m represents an integer of 10 or more. R ⁵ and R ⁶ may be the same or different and represent an alkylene group or an arylene group having 1 to 30 carbon atoms. The arylene group is a substituent The substituent represents an alkyl group having 1 to 30 carbon atoms. R ¹ to R 4 may be the same or different, and each of R 1 to R ⁴ may have an alkyl group having 1 to 30 carbon atoms, a phenyl group, or a phenoxy group. (indicates the group)
<Polyimide resin>
It is preferable that the polyimide resin has a weight average molecular weight of 5000 or more. By setting the weight average molecular weight to 5000 or more, the toughness and flexibility of the composition of the present invention can be improved. Moreover, it is preferable that the weight average molecular weight is 1,000,000 or less. By setting the weight average molecular weight to 1,000,000 or less, the dispersibility of the filler in the composition of the present invention can be improved, and the thermal conductivity can be improved.

As a method for measuring the weight average molecular weight, it can be calculated in terms of polystyrene using a GPC device using a solution in which a polyimide resin is dissolved.

<Epoxy resin>
The epoxy resin used in the present invention is not particularly limited, but from the viewpoint of lowering the elastic modulus of the composition after curing, improving flexibility, and reducing contact thermal resistance at the contact interface, the epoxy resin has a siloxane skeleton. Epoxy resin containing is preferred. Examples of such epoxy resins include X-40-2695B and X-22-2046 manufactured by Shin-Etsu Chemical Co., Ltd. Examples of flexible epoxy resins that do not contain a siloxane skeleton include YX7400, YX7110, YX7180, and YX7105 manufactured by Mitsubishi Chemical Corporation.

The epoxy resin used in the present invention has a triazine skeleton from the viewpoint of increasing heat resistance at high temperatures of 200°C or higher, preventing brittleness of the composition after long-term use at 200°C, and improving releasability. An epoxy resin containing is preferred. Examples of such epoxy resins include TEPIC-PAS B26L, TEPIC-PAS B22, TEPIC-S, TEPIC-VL, TEPIC-FL, and TEPIC-UC manufactured by Nissan Chemical Co., Ltd.

The epoxy resin used in the present invention is preferably a crystalline epoxy resin from the viewpoint of improving thermal conductivity. The crystalline epoxy resin is an epoxy resin having a mesogenic skeleton such as a biphenyl group, a naphthalene skeleton, an anthracene skeleton, a phenylbenzoate group, or a benzanilide group. Products compatible with such epoxy resins include JERYX4000, JERYX4000H, JERYX8800, JERYL6121H, JERYL6640, JERYL6677, and JERYX7399 manufactured by Mitsubishi Chemical Corporation, and NC3000, NC3000H, and NC300 manufactured by Nippon Kayaku Co., Ltd. 0L, CER-3000L Examples include YSLV-80XY and YDC1312 manufactured by Nippon Steel Chemical Co., Ltd., and HP4032, HP4032D, and HP4700 manufactured by DIC Corporation.

Further, the epoxy resin used in the present invention is preferably an epoxy resin having a fluorene skeleton from the viewpoint of improving the dispersibility of the filler and improving the thermal conductivity. Examples of such epoxy resins include PG100, CG500, CG300-M2, EG200, and EG250 manufactured by Osaka Gas Chemical Co., Ltd.

Moreover, the epoxy resin used in the present invention is preferably a glycidylamine type epoxy resin from the viewpoint of having high affinity with polyimide, improving crosslinking density with polyimide, and improving heat resistance. Examples of such epoxy resins include JER630, JER630LSD, and JER604 manufactured by Mitsubishi Chemical Corporation.

Further, the epoxy resin used in the present invention is preferably a liquid epoxy resin from the viewpoint of lowering the viscosity when dispersing the filler. Here, the liquid epoxy resin is one that exhibits a viscosity of 150 Pa·s or less at 25°C and 1.013×10 ⁵ N/m ² , such as bisphenol A epoxy resin, bisphenol F epoxy resin, alkylene epoxy resin, etc. Examples include oxide-modified epoxy resins and glycidylamine-type epoxy resins. Products compatible with such epoxy resins include JER827, JER828, JER806, JER807, JER801N, JER802, YX7400, JER604, JER630, JER630LSD manufactured by Mitsubishi Chemical Corporation, and Epicron 840S and Epicron 850S manufactured by DIC Corporation. , Epicron 830S, Epicron 705, Epicron 707, YD127, YD128, PG207N, PG202 manufactured by Nippon Steel Chemical Co., Ltd., TEPIC-PASB26L, TEPIC-PASB22, TEPIC-VL, TEPIC-FL, manufactured by Nissan Chemical Co., Ltd. Examples include TEPIC-UC.

Further, the number of epoxy resins used in the present invention may be one type or a combination of two or more types. The content of the epoxy resin is preferably 0.1 parts by weight or more based on 100 parts by weight of polyimide from the viewpoint of improving the toughness of the composition and heat resistance at high temperatures, and 15 parts by weight from the viewpoint of improving the flexibility of the composition. Part or less is preferred.

Furthermore, the composition of the present invention may contain a curing agent if necessary. By combining an epoxy resin and a curing agent, the curing of the epoxy resin can be accelerated and cured in a short time. As the curing agent, imidazoles, polyhydric phenols, acid anhydrides, amines, hydrazides, polymercaptans, Lewis acid-amine complexes, latent curing agents, etc. can be used.

Examples of imidazoles include Curazole 2MZ, Curazole 2PZ, Curazole 2MZ-A, and Curazole 2MZ-OK (all trade names, manufactured by Shikoku Kasei Kogyo Co., Ltd.). Examples of polyhydric phenols include SUMILITE RESIN PR-HF3, SUMILITE RESIN PR-HF6 (trade name, produced by Sumitomo Bakelite Co., Ltd.), Kayahard KTG-105, Kayahard NHN (trade name, produced by Nippon Kayaku Co., Ltd.). ), Phenolyte TD2131, Phenolyte TD2090, Phenolyte VH-4150, Phenolyte KH-6021, Phenolyte KA-1160, Phenolyte KA-1165 (all trade names, manufactured by DIC Corporation). In addition, as the latent curing agent, dicyandiamide type latent curing agent, amine adduct type latent curing agent, organic acid hydrazide type latent curing agent, aromatic sulfonium salt type latent curing agent, microcapsule type latent curing agent , photocurable latent curing agents.

Examples of dicyandiamide type latent curing agents include DICY7, DICY15, DICY50 (all trade names, manufactured by Japan Epoxy Resins Co., Ltd.), Amicure AH-154, and Amicure AH-162 (all trade names, manufactured by Ajinomoto Fine Techno Co., Ltd.). Examples include. Examples of amine adduct type latent curing agents include Amicure PN-23, Amicure PN-40, Amicure MY-24, Amicure MY-H (all trade names, manufactured by Ajinomoto Fine Techno Co., Inc.), and FujiCure FXR-1030 (trade name). , manufactured by Fuji Kasei Co., Ltd.). Examples of the organic acid hydrazide type latent curing agent include Amicure VDH and Amicure UDH (all trade names, manufactured by Ajinomoto Fine Techno, Inc.). Examples of the aromatic sulfonium salt type latent curing agent include Sanaid SI100, Sanaid SI150, and Sanaid SI180 (all trade names, manufactured by Sanshin Kagaku Kogyo Co., Ltd.). Examples of the microcapsule type latent curing agent include those obtained by encapsulating each of the above curing agents with a vinyl compound, a urea compound, or a thermoplastic resin. Among them, examples of microcapsule type latent curing agents obtained by treating an amine adduct type latent curing agent with isocyanate include Novacure HX-3941HP, Novacure HXA3922HP, Novacure HXA3932HP, and Novacure HXA3042HP (all trade names, manufactured by Asahi Kasei Chemicals Co., Ltd.). Can be mentioned. Examples of the photocurable latent curing agent include Optomer SP and Optomer CP (manufactured by ADEKA Corporation).

When the composition contains a curing agent, the content thereof is preferably 0.1 parts by weight or more and 35 parts by weight or less based on 100 parts by weight of the epoxy resin.

<Coupling agent>
The composition of the present invention may further include a silane coupling agent. The silane coupling agent plays the role of forming a covalent bond between the filler surface and the surrounding resin (equivalent to a binder agent), the role of efficiently transmitting heat, and the role of preventing moisture intrusion, thereby improving insulation reliability. It can play a role in improving the quality of life.

The type of silane coupling agent is not particularly limited, and commercially available products may be used. Considering compatibility with the resin and reducing thermal conductivity defects at the interface between the resin and the filler, a silane coupling agent having a reactive group such as an epoxy group, an amino group, a mercapto group, a ureido group, or a hydroxyl group at the end is used. It is preferable to use

Specific examples of silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane. , 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl- Examples include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-ureidopropyltriethoxysilane. Further, a silane coupling agent oligomer (manufactured by Hitachi Chemical Techno Service Co., Ltd.) represented by the trade name: SC-6000KS2 can also be mentioned. These silane coupling agents may be used alone or in combination of two or more.

The silane coupling agent may be present in a state where the surface of the filler is coated, or may be present in a state separate from the filler.

<Organic solvent>
The composition of the invention may further contain at least one organic solvent. The inclusion of organic solvents allows the composition to be compatible with various molding processes. As the organic solvent, those commonly used in compositions can be used. Specifically, alcohol solvents, ether solvents, ketone solvents, amide solvents, aromatic hydrocarbon solvents, ester solvents, nitrile solvents, etc. can be mentioned. For example, methyl isobutyl ketone, dimethylacetamide, dimethylformamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, γ-butyrolactone, sulfolane, cyclohexanone, and methyl ethyl ketone can be used. These organic solvents may be used alone or in combination of two or more.

<Other ingredients>
In addition to the above-mentioned components, the composition of the present invention can contain other components as necessary. Examples of other components include dispersants, plasticizers, and the like. Examples of dispersants include the product name: DISPERBYK series ("DISPERBYK" is a registered trademark) manufactured by BYK-Chemie Japan Co., Ltd., and the product name: Ajisper series ("Ajisper" is a registered trademark) manufactured by Ajinomoto Fine-Techno Co., Ltd. ), manufactured by Kusumoto Kasei Co., Ltd., product name: HIPLAAD series ("HIPLAAD" is a registered trademark), and manufactured by Kao Corporation, product name: Homogenol series ("Homogenol" is a registered trademark). . These dispersants may be used alone or in combination of two or more.

<Sheet composition>
The sheet-like composition of the present invention is the composition of the present invention in a sheet-like form. A sheet-like composition can be produced, for example, by applying the composition of the present invention onto a support and removing at least a portion of the solvent contained therein, if necessary. By forming a sheet-like composition from the composition of the present invention, when this sheet-like composition is made into a cured product, it can be made into a cured product with excellent thermal conductivity and electrical insulation properties.

The thickness of the sheet composition is not particularly limited and can be appropriately selected depending on the purpose. For example, the thickness can be 50 μm to 500 μm, and preferably 80 μm to 300 μm from the viewpoint of thermal conductivity, electrical insulation, and flexibility.

The sheet composition of the present invention is, for example, a paint of a composition prepared by adding an organic solvent such as triethylene glycol dimethyl ether or cyclohexanone to the composition of the present invention (hereinafter also referred to as "composition paint"). It can be manufactured by coating on a support to form a coating layer (composition layer), then removing at least a portion of the organic solvent from the coating layer and drying. Examples of the support include release films such as PET (polyethylene terephthalate) films.

The composition coating can be applied by a known method. Specifically, it can be carried out by methods such as comma coating, die coating, lip coating, and gravure coating. Examples of methods for forming a composition layer with a predetermined thickness include a comma coating method in which the object to be coated is passed through a gap, and a die coating method in which a composition paint is applied from a nozzle at a controlled flow rate. For example, when the thickness of the coating layer (composition layer) before drying is 50 μm to 500 μm, it is preferable to use the comma coating method.

The drying method is not particularly limited as long as it can remove at least a portion of the organic solvent contained in the composition paint, and can be appropriately selected from commonly used drying methods depending on the organic solvent contained in the composition paint. Generally, a method of heat treatment at about 80°C to 150°C can be mentioned.

When the sheet-like composition (composition layer) contains a curable resin, the sheet-like composition (composition layer) means a state in which the curing reaction has not progressed at all to a state in which the curing reaction has partially progressed. For this reason, a sheet-like composition in which the effect reaction has not progressed at all has flexibility but lacks strength as a sheet. Therefore, when the support such as PET film is removed, the sheet has poor self-supporting properties and may be difficult to handle.

Therefore, from the viewpoint of improving handleability, it is preferable that the composition layer constituting the sheet-like composition is subjected to a semi-curing treatment. That is, the sheet composition is preferably a semi-cured composition that is a B-stage sheet that is further heat-treated until the composition layer becomes a semi-cured state (B-stage state). By semi-curing the composition layer, it is possible to obtain a resin sheet that has excellent thermal conductivity and electrical insulation, and has excellent self-reliance as a B-stage sheet and a long pot life.

The conditions for heat-treating the sheet-like composition are not particularly limited as long as the composition layer can be brought into a B-stage state. The conditions can be appropriately selected depending on the composition of the composition. The heat treatment is preferably carried out by a method selected from hot vacuum pressing, hot roll lamination, etc. in order to reduce voids in the composition layer that occur when applying the composition paint. Thereby, a B-stage sheet with a flat surface can be efficiently manufactured.

Specifically, for example, the composition layer is brought to the B stage by heating and pressurizing the composition layer under reduced pressure (for example, 1 kPa) at a temperature of 100° C. to 200° C. for 1 minute to 3 minutes and a press pressure of 1 MPa to 20 MPa. It can be semi-cured to a state.

Note that it is preferable to apply the composition onto a support and bond two sheets of the dried sheet-like composition together, and then perform the heating and pressure treatment described above to semi-cure the composition to a B-stage state. At this time, it is desirable to bond the coated surfaces of the composition layers (the surfaces where the composition layers are not in contact with the support) to each other. When the composition layers are attached so that they are in contact with each other, both sides of the resulting B-stage sheet-like composition (i.e., the surface that appears when the support is peeled off) become flatter, and the adhesion to the adherend is improved. Becomes good. Heat dissipating components and electronic components, which will be described later, produced using such a sheet-like composition exhibit high thermal conductivity.

The thickness of the B-stage sheet can be appropriately selected depending on the purpose. For example, it can be 50 μm to 500 μm, and preferably 80 μm to 300 μm from the viewpoint of thermal conductivity, electrical insulation, and flexibility. Moreover, it can also be produced by hot pressing while laminating two or more layers of resin sheets.

The residual rate of volatile components in the B-stage sheet is preferably 2.0% by mass or less, and 1.0% by mass or less, from the viewpoint of suppressing bubble formation due to outgas generation when curing the composition layer. is more preferable, and even more preferably 0.8% by mass or less. The solvent residual rate is determined from the change in mass before and after drying by drying a sample obtained by cutting the B-stage sheet into 40 mm x 40 mm in a constant temperature bath preheated to 190° C. for 2 hours.

<Cured product>
The cured product of the present invention is a cured product made of the composition or sheet composition of the present invention.

Further, the cured product of the present invention preferably has a thermal conductivity of 0.3 to 10 W/mK at 25°C and an elastic modulus of 0.01 to 100 MPa at -70°C. The thermal conductivity of the cured product at 25° C. is more preferably 0.3 to 8 W/mK, even more preferably 0.3 to 5 W/mK. The elastic modulus of the cured product of the present invention at -70°C is more preferably 0.1 to 90 MPa, and even more preferably 1 to 85 MPa.

In order to make the thermal conductivity of the cured product of the present invention 0.3 to 10 W/mK at 25°C, it is necessary to appropriately select the resin in the composition, and in particular to select a polyimide resin as the resin, and to The method of controlling the molecular weight, the appropriate selection of the filler in the composition, especially the inclusion of a combination of (A) and (B) as a filler with a thermal conductivity of 1 W/mK or more, Examples of methods include controlling the average value of the aspect ratio and maximum length of ), controlling the volume ratio of (A) and (B), and appropriately selecting the composition of (A).

In order to set the elastic modulus of the cured product of the present invention at -70°C to be 0.01 to 100 MPa, the resin in the composition must be appropriately selected, and in particular, the resin may be a urethane resin, a silicone resin, or an acrylic resin. Examples include a method of selecting the filler from a group, a method of appropriately selecting the filler in the composition, and a method of controlling the volume ratio of (A) and (B) in particular.

Further, the cured product of the present invention preferably has a dielectric strength voltage of 5 kV/mm or more. The dielectric strength voltage of the cured product is preferably 10 kV/mm or more, more preferably 20 kV/mm or more. Further, although there is no particular limit to the upper limit of the dielectric strength voltage, a practical upper limit is about 200 kV/mm.

In order to make the dielectric strength voltage of the cured product of the present invention 5 kV/mm or more, as mentioned above, it is necessary to appropriately select the filler in the composition, especially by controlling the volume ratio of (A) and (B), and by controlling the volume ratio of (A) and (B). Examples include a method of appropriately selecting the compositions of A) and (B).

The cured product can be produced by curing an uncured composition, a sheet composition, a B-stage composition, or a B-stage sheet composition. The method of curing treatment can be appropriately selected depending on the structure of the composition, the purpose of the composition, etc., but heat and pressure treatment is preferable.

For example, a composition containing a curable resin can be obtained by heating an uncured sheet composition or a B-stage sheet at 80°C to 250°C for 1 hour to 10 hours, preferably at 100°C to 200°C for 1 hour to 8 hours. A cured product of a sheet-like composition formed from the product is obtained. The heat treatment is preferably performed while applying a pressure of 1 KPa to 1 MPa.

A sheet-like composition having a composition layer containing a curable resin obtained by the above method has high thermal conductivity and self-supporting properties. An example of a method for manufacturing a sheet composition having a composition layer containing a curable resin includes the following method. First, a B-stage sheet with PET film on both sides is heated at a temperature of 80°C to 200°C for 1 to 8 hours. Thereafter, the PET film of the sheet composition is removed to obtain a sheet composition having a cured composition layer.

<Multilayer sheet>
The multilayer sheet of the present invention is a sheet having the sheet composition or cured product of the present invention and an adhesive layer. Therefore, the multilayer sheet of the present invention is a sheet having two or more layers including an adhesive layer and a sheet composition or cured product. The multilayer sheet of the present invention preferably has an adhesive layer on at least a portion of one or both surfaces of the sheet composition or cured product. The adhesive layer in the multilayer sheet may be in direct contact with the sheet composition or cured product of the present invention, or there may be a layer such as a metal layer between the sheet composition or cured product and the adhesive layer. Also good.

The type and material of the adhesive layer are not particularly limited, but the adhesive layer includes at least one selected from the group consisting of epoxy resin, phenol resin, urethane resin, silicone resin, acrylic resin, polyimide resin, and polyamideimide resin. More preferably, from the viewpoint of adhesive strength, at least one selected from the group consisting of epoxy resins, urethane resins, acrylic resins, and polyimide resins is included.

The method for producing the multilayer sheet is not particularly limited, and can be carried out, for example, by a method selected from hot vacuum pressing, hot roll lamination, and the like.

<Heat dissipation parts>
The heat dissipation component of the present invention is a component used for heat dissipation purposes, which includes the composition of the present invention, the cured product of the present invention, or the multilayer sheet of the present invention. The heat dissipation component of the present invention is not limited by the members used. The heat dissipation component of the present invention is, for example, a heating element, at least one selected from the group consisting of the composition of the present invention, a sheet composition, and a cured product, and a cooling body, which are laminated in this order. . In this order, a heat diffusion layer (for example, a heat spreader) or the like may be included in between.

The heating element in the heat dissipation component may have a surface temperature that does not exceed 200°C. When the surface temperature of the heating element is 200° C. or less, the flexibility of the composite thermally conductive sheet of this embodiment is prevented from rapidly decreasing, and the decrease in heat dissipation characteristics tends to be suppressed. The composite thermally conductive sheet of this embodiment can be used, for example, in the range of -20°C to 150°C. For this reason, examples of suitable heating elements include semiconductor packages, displays, LEDs (light emitting diodes), electric lights, and the like.

The cooling body in the heat dissipation component is not particularly limited, and may be a typical cooling body applied to a heat dissipation system. Heat sinks include heat sinks using aluminum or copper fins, plates, etc., aluminum or copper blocks connected to heat pipes, and aluminum or copper blocks in which cooling liquid is circulated by a pump. Examples include.

<Electronic parts>
The electronic component of the present invention is a component used for electronic purposes, which includes the composition of the present invention, the cured product of the present invention, or the multilayer sheet of the present invention. Therefore, the composition of the present invention can be applied, for example, to a substrate for connecting a semiconductor integrated circuit.

A semiconductor integrated circuit connection board is used to connect semiconductor integrated circuits (bare chips) that are cut into pieces after an element is formed on a semiconductor substrate such as silicon, and includes (A) wiring made of an insulating layer and a conductor pattern; The shape, material, and manufacturing method are not particularly limited as long as it has at least one substrate layer, (B) a layer on which no conductor pattern is formed, and (C) an adhesive layer. Therefore, the most basic structure is A/C/B, but it also includes multilayer structures such as A/C/B/C/B.

(A) A wiring board layer consisting of an insulator layer and a conductor pattern is a layer having a conductor pattern for connecting the electrode pad of a semiconductor element and the outside of the package (printed circuit board, etc.), and is a layer that has a conductor pattern on one or both sides of the insulator layer. A conductor pattern is formed on the surface.

The insulating layer here is made of plastic such as polyimide, polyester, polyphenylene sulfide, polyether sulfone, polyether ether ketone, aramid, polycarbonate, polyarylate, or a composite material such as epoxy resin-impregnated glass cloth, and has a thickness of 10 to An insulating film having a flexibility of 125 μm or a ceramic substrate such as alumina, zirconia, soda glass, or quartz glass is suitable, and a plurality of layers selected from these may be laminated. Further, if necessary, the insulating layer can be subjected to surface treatments such as hydrolysis, corona discharge, low-temperature plasma, physical roughening, and adhesion-promoting coating.

The conductor pattern is generally formed by either a subtractive method or an additive method, but either method may be used.

In the subtractive method, a metal plate such as copper foil is bonded to an insulating layer with an insulating adhesive, or a precursor of the insulating layer is laminated on the metal plate, and an insulating layer is formed by heat treatment etc. Patterns are formed by etching the material produced using chemical treatment. Specific examples of the material include copper-clad materials for rigid or flexible printed circuit boards, TAB tape, and the like. Among these, copper-clad materials for flexible printed circuit boards and TAB tapes, which have at least one layer of polyimide film as an insulating layer and copper foil as a conductor pattern, are preferably used.

In the additive method, a conductive pattern is directly formed on an insulating layer by electroless plating, electrolytic plating, sputtering, or the like. In either case, the formed conductor may be plated with a highly corrosion-resistant metal to prevent corrosion. Further, via holes may be formed in the wiring board layer as necessary, and conductor patterns formed on both surfaces may be connected by plating.

(B) The layer on which no conductor pattern is formed is substantially a uniform layer independent of (A) a wiring board layer consisting of an insulator layer and a conductor pattern or (C) an adhesive layer, and is a semiconductor integrated circuit. Reinforcement and dimensional stabilization of connection boards (referred to as reinforcing plates or stiffeners), electromagnetic shielding between the outside and IC, heat dissipation of ICs (referred to as heat spreaders and heat sinks), and connection boards for semiconductor integrated circuits. It has functions such as imparting flame retardancy and providing distinguishability based on the shape of the substrate for connecting semiconductor integrated circuits. Therefore, the shape is not limited to a layered shape, but may also have a fin structure for heat radiation, for example. It may be an insulator or a conductor as long as it has the above function, and the material is not particularly limited. Metals include copper, iron, aluminum, gold, silver, nickel, titanium, stainless steel, etc. Inorganic materials include alumina, zirconia, soda glass, quartz glass, carbon, etc. Organic materials include polyimide, polyamide, and polyester. , vinyl-based, phenolic-based, epoxy-based, and other polymer materials. Composite materials made from a combination of these can also be used. Examples include those in the form of thin metal plating on a polyimide film, those in which carbon is kneaded into a polymer to make it conductive, and those in which a metal plate is coated with an organic insulating polymer. In addition, there is no limitation to performing various surface treatments similar to the insulating layer included in the above (A) wiring board layer.

(C) The adhesive layer is obtained by peeling off the protective film layer of the sheet-like composition of the present invention, and one adhesive layer surface is composed of (B) a layer on which no conductor pattern is formed, and the other adhesive layer surface. (A) heat lamination with a wiring board layer consisting of an insulating layer and a conductor pattern, and then (C) heat curing of the adhesive layer to obtain a semiconductor connection board. Further, if necessary, the adhesive layer (C) can be heated and cured while being pressurized using a hot press or the like.

The connection method between the semiconductor integrated circuit connection board and IC can be any of TAB gang bonding and single point bonding, wire bonding used in lead frames, resin sealing in flip chip mounting, anisotropic conductive film connection, etc. good. Furthermore, a package called CSP is also included in the electronic component of the present invention.

The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. First, the evaluation methods performed in Examples 1 to 8 and Comparative Examples 1 to 5 will be described.

<Creating a sample for evaluation>
The sheet compositions prepared in the Examples and Comparative Examples described later were cut into 50 mm squares, the protective film of one side of the adhesive sheet having a 50 μm thick adhesive layer was removed, and the sheets were cut out at 120° C. and 0.4 MPa. The adhesive layers were laminated and laminated. This process was repeated to form an adhesive layer with a thickness of 200 μm, and then heat curing was performed at 180° C. for 3 hours to obtain a cured product sample for evaluation.

(1) Thermal conductivity:
A cured product sample for thermal conductivity evaluation was obtained by cutting out the cured product sample for evaluation into a 10 mm square.

After blackening the cured product sample for thermal conductivity evaluation using graphite spray, the thermal diffusivity was evaluated using the xenon flash method (trade name: LFA447 nanoflash, manufactured by NETZSCH). The product of this value, the density of the cured product sample for evaluation measured by the Archimedes method, and the specific heat of the cured product sample for evaluation determined by DSC (differential scanning calorimeter; trade name: DSC Pyris 1, manufactured by Perkin Elmer). From this, the thermal conductivity in the thickness direction of the cured product was determined. The results are shown in Table 1.

The specific heat was determined by placing 10.0 mg of a cured product sample for evaluation in an aluminum pan, raising the temperature from room temperature to 200 °C at a rate of 10 °C/min, and holding it for 5 minutes after reaching 200 °C. The temperature dropped in minutes. Similarly, 26.8 mg of sapphire was placed in an aluminum pan as a reference material and measured under the same conditions. Furthermore, as a blank, an empty aluminum pan containing no sample was measured under the same conditions. The Heat Flow value at 25° C. of each DSC curve was read, and the specific heat capacity was calculated using the following formula 1.

Cp is the specific heat of the cured product sample for evaluation, C'p is the specific heat of the reference material (sapphire) at 25°C, h is the difference between the DSC curves of the empty container and the cured product sample for evaluation, H is the empty container and the reference material (sapphire) m represents the mass (g) of the cured product sample for evaluation, and m' represents the mass (g) of the reference material (sapphire). Cp=(h/H)×(m'/m)×C'p...Formula 1
The thermal conductivity in the thickness direction of the cured material sample for thermal conductivity evaluation was determined from the measured product of thermal diffusivity, density, and specific heat. The results are shown in the table.

(2) -70℃ elastic modulus:
The cured product sample for evaluation was cut into a 5 mm x 20 mm square and was used as a cured product sample for -70°C elastic modulus evaluation.

The elastic modulus of the -70°C elastic modulus evaluation sample was measured using a dynamic viscoelasticity measuring device DVA-200 manufactured by IT Kansei Control Co., Ltd. The measurement conditions were a heating rate of 5°C/min, a measurement frequency of 1Hz, a storage modulus at each temperature in the range of -130°C to 150°C, and a storage modulus of -70°C. The value was defined as the -70°C elastic modulus.

(3) Insulation:
A cured product sample for insulation evaluation was obtained by cutting out the cured product sample for evaluation into a 30 mm x 30 mm square.
Place aluminum foil on one side of the cured product sample for insulation evaluation and a φ25 mm electrode on the other side, and measure the dielectric strength using an AC withstand voltage measuring device at room temperature at an AC voltage increase rate of 0.5 kV/sec. It was measured.

The obtained dielectric strength voltage was divided by the thickness of the cured material sample for insulation evaluation, and the obtained value was evaluated based on the following criteria.
5kV/mm or more: 〇 Less than 5kV/mm: ×

(4) Aspect ratio, average value of maximum length The aspect ratio is determined by measuring the filler before compounding (that is, the filler in raw material state) using a scanning electron microscope (for example, manufactured by Hitachi, Ltd., product name: FE-SEM S4700). Observe 50 particles using ) was calculated.

In addition, when using a plurality of fillers as raw materials, the measurement is performed for each filler that is the raw material.

(5) Average particle size (D50)
The average particle size (D50) of the filler is measured using a laser diffraction method for the filler before blending (that is, the filler in the raw material state), and when the weight cumulative particle size distribution curve is drawn from the small particle size side, the weight The value corresponds to the particle diameter at which the cumulative value is 50%. Particle size distribution measurement using a laser diffraction method uses a laser diffraction scattering particle size distribution analyzer (for example, LS230 manufactured by Beckman Coulter Co., Ltd.) to calculate the particle size at which the cumulative weight becomes 50%, and then It was defined as the average particle diameter (D50).

In addition, when using a plurality of fillers as raw materials, the measurement is performed for each filler that is the raw material.

(6) Imidization rate of the synthesized polyimide resin First, the infrared absorption spectrum of the polymer was measured, and the presence of absorption peaks (around 1780 cm ⁻¹ and around 1377 cm ⁻¹ ) of the imide structure caused by the polyimide resin was confirmed. Next, the polymer was heat-treated at 350° C. for 1 hour, and then the infrared absorption spectrum was measured again, and the peak intensities around 1377 cm ⁻¹ before and after the heat treatment were compared. The imidization rate of the polymer resin before heat treatment was determined by setting the imidization rate of the polymer resin after heat treatment as 100%.

The raw materials used in the examples are as follows.

<Resin>
・Polyimide (1)
<Polyimide (1) synthesis>
A stirrer, a thermometer, a nitrogen introduction tube, and a dropping funnel were installed in a 500 ml four-necked flask, and under a nitrogen atmosphere, 132.70 g of triethylene glycol dimethyl ether and X-22-168A (manufactured by Shin-Etsu Chemical Co., Ltd.) 121 were added. 00g was charged and stirred and dissolved at 60°C. Thereafter, while stirring at 120°C, 2.01 g of BAHF:2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (manufactured by Tokyo Chemical Industry Co., Ltd.), X-22-161A (manufactured by Shin-Etsu Chemical Co., Ltd.) Co., Ltd.) was added thereto and stirred for 1 hour. Thereafter, the temperature was raised to 200° C., stirred for 3 hours, and then cooled to room temperature to obtain polyimide (1) (solid content concentration 60.0% by weight). The weight average molecular weight of the solid content was measured to be 32,850, and the imidization rate was measured to be 99%.

・YX7400: Bifunctional linear epoxy resin (manufactured by Mitsubishi Chemical Corporation)
<Curing agent>
・X-22-161A: Diaminopolysiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.)
<Filler (A)>
・AA3: Alumina particles (average particle size D50: 3 μm, thermal conductivity: 30 W/mK) (manufactured by Sumitomo Chemical Co., Ltd.)
・FAN-f05: Aluminum nitride particles (average particle size D50: 5 μm, thermal conductivity: 170 W/mK) (manufactured by Furukawa Electronics Co., Ltd.)
<Filler (B)>
・AlN whiskers (average maximum length: 15 μm, thermal conductivity: 170 W/mK) (manufactured by U-MAP Co., Ltd.)
・ACP: Graphite (average maximum length: 20 μm, thermal conductivity: 1500 W/mK) (manufactured by Nippon Graphite Co., Ltd.)
・UHP-2: Boron nitride (average maximum length: 11 μm, thermal conductivity: 170 W/mK) (manufactured by Showa Denko K.K.)
<Other fillers>
・Cerasur BMF: Plate-shaped alumina (average maximum length: 5 μm, thermal conductivity: 20 W/mK) (manufactured by Kawai Lime Industry Co., Ltd.)

<Examples 1 to 8, Comparative Examples 1 to 5>
Examples 1 to 8 and Comparative Examples 1 to 5 were blended to have the composition shown in the table, triethylene glycol dimethyl ether was added so that the solid content concentration was 74% by weight, and a rotary mixer (Thinky) was used. Co., Ltd.) at 1800 rpm for 10 minutes to prepare a composition solution.

The composition solution was coated with a bar coater on a 38 μm thick polyethylene terephthalate film (“Film Biner” GT manufactured by Fujimori Industries Co., Ltd.) with a silicone mold release agent to a dry thickness of 80 μm (hereinafter referred to as composition coating). membrane). It was dried at 120°C for 30 minutes, and a protective film was attached at 120°C and 0.4 MPa to produce a sheet-like composition. Next, the results of various evaluations are shown in the table.

From the table, in Examples 1 to 4 and Comparative Examples 1 to 3, the filler volume ratio is constant and the filler (B) volume ratio is varied. Comparing Comparative Example 1 with 0 filler (B), Examples 1 to 4, and Comparative Examples 1 to 2, it was confirmed that the thermal conductivity was improved. On the other hand, in Comparative Examples 2 and 3 in which the proportion of filler (B) was 50% or more, a remarkable increase in the elastic modulus was observed, but in Examples 1 to 4, no increase in the elastic modulus was observed.

From Comparative Example 1, Comparative Example 4, and Example 3, Comparative Example 4 and Comparative Example 1 using filler (B) whose average value of maximum length is 5 have the same thermal conductivity, and the average value of maximum length is 5. The thermal conductivity was lower than that of Example 3 using filler (B) with an average value of 15.

Comparative Example 5 and Example 7 show that regardless of the filler volume fraction, high thermal conductivity can be achieved while suppressing an increase in the elastic modulus, as seen in Examples 1 to 4 and Comparative Examples 1 to 3.

According to Example 5, regardless of the material of the filler (A), and according to Examples 6 and 8, regardless of the material of the filler (B), high thermal conductivity can be achieved while suppressing an increase in the elastic modulus.

However, in Comparative Example 4, the numerical value in the "Aspect ratio of filler (B)" column means the aspect ratio of other fillers, and the numerical value in the "Average value of maximum length of filler (B)" column means the other filler. The value in the "Volume ratio of (A) and (B) ((A):(B))" column is the average value of the maximum length of fillers in (A) and other fillers. means.

Claims (13)

A composition comprising a resin and a filler having a thermal conductivity of 1 W/mK or more,
The resin consists only of polyimide resin and epoxy resin,
The content of the epoxy resin is 0.1 parts by weight or more and 15 parts by weight or less based on 100 parts by weight of the polyimide,
The filler has an aspect ratio (average maximum length/average minimum length) of 1.0 to 1.9 (hereinafter, filler with an aspect ratio of 1.0 to 1.9 is referred to as (A ),
and a filler with an aspect ratio of 2 or more and an average maximum length of 10.5 to 200.0 μm (hereinafter, a filler with an aspect ratio of 2 or more and an average maximum length of 10.5 to 200.0 μm) , (denoted as (B)),
The volume ratio of (A) and (B) is (A):(B)=95:5 to 55:45, and the total volume ratio, which is the sum of the volume ratios of (A) and (B), is 15 % to 80% by volume. The composition according to claim 1, comprising a silane coupling agent. The filler is at least one member selected from the group consisting of alumina, silica, boron nitride, aluminum nitride, zinc oxide, magnesium oxide, boehmite, graphite, graphene, carbon nanotubes, cellulose nanofibers, and carbon fibers. Item 2. The composition according to item 1 or 2. (A) is at least one selected from the group consisting of alumina, silica, aluminum nitride, zinc oxide, magnesium oxide, and boehmite,
The composition according to any one of claims 1 to 3, wherein (B) is aluminum nitride. The composition according to any one of claims 1 to 4, wherein the average particle size D50 of the (A) is 1.0 μm to 100.0 μm. Any one of claims 1 to 5 , wherein the polyimide resin is a polyimide resin containing 60 mol% or more of diamine residues having a structure represented by the following general formula (1) out of 100 mol% of the total diamine residues. The composition described in .

(In the general formula (1), m represents an integer of 10 or more. R ⁵ and R ⁶ may be the same or different and represent an alkylene group or an arylene group having 1 to 30 carbon atoms. The arylene group is a substituent The substituent represents an alkyl group having 1 to 30 carbon atoms. R ¹ to R 4 may be the same or different, and each of R 1 to R ⁴ may have an alkyl group having 1 to 30 carbon atoms, a phenyl group, or a phenoxy group. (indicates the group) The sheet-like composition according to any one of claims 1 to 6 , which has a sheet-like shape. A cured product comprising the composition according to any one of claims 1 to 7 . The cured product according to claim 8 , which has a thermal conductivity of 0.3 to 10 W/mK at 25°C and an elastic modulus of 0.01 to 100 MPa at -70°C. The cured product according to claim 8 or 9 , having a dielectric strength voltage of 5 kV/mm or more. A multilayer sheet comprising the composition according to claim 7 or the cured product according to any one of claims 8 to 10 , and an adhesive layer. A heat dissipating component comprising the composition according to any one of claims 1 to 7 , the cured product according to any one of claims 8 to 10 , or the multilayer sheet according to claim 11 . An electronic component comprising the composition according to any one of claims 1 to 7 , the cured product according to any one of claims 8 to 10 , or the multilayer sheet according to claim 11 .