JP2023069126A - Composition, epoxy resin, and material for electronic components including the same - Google Patents

Abstract

To provide a composition for electronic components that efficiently conducts the heat generated inside an electronic apparatus and a mesomorphic polymerizable compound for use therein.SOLUTION: The present invention discloses at least one chiral compound comprising an isosorbide skeleton or a binaphthyl skeleton and a phenolic hydroxyl group, a composition comprising the compound and at least one epoxy compound, desirably a rodlike liquid crystalline compound, the composition comprising a chiral phase composed of a blue phase, and an epoxy resin formed by curing the composition.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a composition for electronic components that efficiently conducts heat generated inside an electronic device, and a polymerizable compound having liquid crystallinity used therein.

2. Description of the Related Art In recent years, in semiconductor devices for power control of hybrid vehicles and electric vehicles, CPUs for high-speed computers, and the like, high thermal conductivity is desired for packaging materials so that the temperature of internal semiconductors does not become too high. That is, the ability to effectively dissipate the heat generated from the semiconductor chip to the outside has become important.

As a method for solving such a heat dissipation problem, there is a method of contacting a heat-generating part with a highly thermally conductive material (heat-dissipating member) to guide heat to the outside and dissipate the heat. Materials with high thermal conductivity include inorganic materials such as metals and metal oxides. However, such inorganic materials have problems in workability, insulation, etc., and it is very difficult to apply them alone as fillers for semiconductor packages. Therefore, development of heat dissipating members with high thermal conductivity by combining these inorganic materials and resins is underway.

High thermal conductivity of composite materials is generally achieved by adding large amounts of inorganic fillers such as metal fillers to general-purpose resins such as polyethylene resins, polyamide resins, polystyrene resins, acrylic resins, and epoxy resins. rice field. However, the thermal conductivity of inorganic fillers is a value specific to the substance and has a fixed upper limit. Therefore, a method of increasing the thermal conductivity of the composite material by improving the thermal conductivity of the resin has been widely attempted. As means for actually increasing the thermal conductivity, for example, a method using a material having liquid crystallinity is known (Non-Patent Document 1).

Liquid Crystal, Vol. 20, No. 3, pp. 148 (2016) Liquid Crystals, Vol. 14, p. 911 (1993) Nature Materials, Vol. 1, p. 64 (2002)

An object of the present invention is to provide an epoxy resin having high thermal conductivity both in the in-plane direction and in the thickness direction. Another object of the present invention is to provide an epoxy resin having excellent dimensional stability.

The present inventors have found that by curing a composition exhibiting a blue phase, an epoxy resin having a nanostructure in which the blue phase is immobilized can be obtained, and that the epoxy resin has desired properties. perfected the invention.

The epoxy resin of the present invention has high thermal conductivity both in the in-plane direction and in the thickness direction. Therefore, it can be suitably used as a heat dissipation material for power semiconductors and the like.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. Moreover, the present invention is not limited to the embodiments.

The present invention includes the following items.

[1] A composition containing at least one epoxy compound and at least one chiral compound and having a chiral phase.

[2] The composition according to item 1, wherein the epoxy compound is a rod-like liquid crystalline compound.

式（１）中、Ｒ^ｅｐは、独立して、オキシラニルを含む炭素数２から１２の基であり、隣り合わないＣＨ_２はＯで置換されていてもよく、Ｘは、独立して、単結合、－ＣＨ_２ＣＨ_２－、－ＣＨ_２Ｏ－、－ＣＨ＝ＣＨ－、－Ｃ≡Ｃ－、－ＯＣＯ－、または－ＣＯＯ－であり、Ｒ^１は、独立して、水素、フッ素、炭素数１から８のアルキル、炭素数１から８のアルコキシ、炭素数２から８のアルケニル、またはＲ^ｅｐであり、これらアルキル、アルコキシ、およびアルケニルの１つの－ＣＨ_２－は－ＣＯ－で置換していても良く、Ａは１，４－フェニレン、シクロヘキサン－１，４－ジイル、シクロヘキセン－１，４－ジイルであり、ｎは０から２である。 [3] The composition according to item 2, wherein the epoxy compound is a compound represented by formula (1).

In formula (1), R ^ep is independently a group having 2 to 12 carbon atoms including oxiranyl, non-adjacent CH ₂ may be substituted with O, and X is independently a single a bond, —CH ₂ CH ₂ —, —CH ₂ O—, —CH═CH—, —C≡C—, —OCO—, or —COO—, and R ¹ is independently hydrogen, fluorine, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, alkenyl having 2 to 8 carbon atoms, or R ^ep , wherein one —CH ₂ — of these alkyl, alkoxy or alkenyl is substituted with —CO—; A is 1,4-phenylene, cyclohexane-1,4-diyl, cyclohexene-1,4-diyl, and n is 0 to 2.

[4] The composition according to Item 1, wherein the chiral compound is isosorbide or a binaphthyl derivative.

[5] The composition according to Item 1, wherein the chiral phase is a blue phase.

[6] The composition according to any one of Items 1 to 5, further comprising a curing agent.

[7] The composition according to Item 6, wherein at least one curing agent is a chiral compound.

[8] The composition according to any one of Items 1 to 7, further comprising an inorganic filler.

[9] An epoxy resin obtained by curing the composition according to any one of [1] to [8].

[10] The epoxy resin according to item 9, wherein the blue phase of the composition is immobilized.

[11] An electronic component material using the epoxy resin according to item 9 or 10.

[12] A heat dissipating material obtained from the electronic component material according to item 11, wherein the self-assembled structure derived from the blue phase includes a structure immobilized by polymerization.

式（ＣＬ－１）中、それぞれの芳香環上の少なくとも１つの水素は、メチル、メトキシ、またはＯＨで置換されてもよい。 [13] A chiral compound represented by formula (CL-1).

In formula (CL-1), at least one hydrogen on each aromatic ring may be replaced with methyl, methoxy, or OH.

The phrase "at least one hydrogen in the ring may be replaced by alkyl having 1 to 10 carbon atoms" is, for example, a It means an embodiment when substituted with a substituent such as.
"Compound (1)" means a compound represented by formula (1), and may also mean at least one compound represented by formula (1).

As described above, the problem of the present application is solved by using a composition that contains at least one epoxy compound and at least one chiral compound, has a chiral phase, and has a blue phase. can.

The blue phase is one form of liquid crystal phase, and is generally a phase that appears in a part of a liquid crystal composition to which a chiral compound is added. The blue phase is usually an unstable phase and is observed in a narrow temperature range during the transition from the nematic phase to the isotropic phase. Types of blue phases include I, II, and III, and in the present invention, these are referred to as blue phases without distinction. A blue phase is an optically isotropic phase.

The composition of the raw material compound contained in the liquid crystal composition of the present invention is not particularly limited. That is, all of the epoxy compound, curing agent, and chiral compound used may have liquid crystallinity, and none of them need to have liquid crystallinity. However, in order to reliably impart liquid crystallinity to the composition, it is easiest and preferable to use an epoxy compound having liquid crystallinity as a raw material compound.

"Liquid crystal epoxy compound"
The liquid crystalline epoxy compound that can be used in the composition of the present invention is not limited and can be selected from known compounds. At this time, it is preferable to use a compound represented by the following formula (1) because it is easy to develop a blue phase.

式（１）中、Ｒ^ｅｐは、独立して、オキシラニルを含む炭素数２から１２の基であり、隣り合わないＣＨ_２はＯで置換されていてもよく、Ｘは、独立して、単結合、－ＣＨ_２ＣＨ_２－、－ＣＨ_２Ｏ－、－ＣＨ＝ＣＨ－、－Ｃ≡Ｃ－、－ＯＣＯ－、または－ＣＯＯ－であり、Ｒ^１は、独立して、水素、フッ素、炭素数１から８のアルキル、炭素数１から８のアルコキシ、炭素数２から８のアルケニル、またはＲ^ｅｐであり、これらアルキル、アルコキシ、およびアルケニルの１つの－ＣＨ_２－は－ＣＯ－で置換していても良く、Ａは１，４－フェニレン、シクロヘキサン－１，４－ジイル、シクロヘキセン－１，４－ジイルであり、ｎは０から２である。

In formula (1), R ^ep is independently a group having 2 to 12 carbon atoms including oxiranyl, non-adjacent CH ₂ may be substituted with O, and X is independently a single a bond, —CH ₂ CH ₂ —, —CH ₂ O—, —CH═CH—, —C≡C—, —OCO—, or —COO—, and R ¹ is independently hydrogen, fluorine, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, alkenyl having 2 to 8 carbon atoms, or R ^ep , wherein one —CH ₂ — of these alkyl, alkoxy or alkenyl is substituted with —CO—; A is 1,4-phenylene, cyclohexane-1,4-diyl, cyclohexene-1,4-diyl, and n is 0 to 2.

Among the compounds represented by the above formula (1), examples of particularly suitable compounds are shown below.

In formulas (1-1) to (1-36), R ^ep independently represents an oxiranyl-containing group having 2 to 12 carbon atoms.

In the compounds represented by the above formulas (1-1) to (1-36), in order to solve the problems of the present invention, formulas (1-4) to (1-19) and formula (1- 23) to preferably one of the compounds represented by the formula (1-25). These compounds have a wide liquid crystal temperature range, which is suitable for curing. Among these compounds, one of the compounds represented by formula (1-25) from formula (1-6), formula (1-9), (1-10), and formula (1-23) is selected. is more preferable for the same reason. In order to further improve the thermal stability of the cured product, it is most preferable to select one of the compounds represented by formulas (1-6), (1-9) and (1-10). preferable.

In these compounds of formulas (1-1) to (1-36), it is preferable that the two R ^ep have different structures because they tend to provide a wide liquid crystal temperature range.

The content of these liquid crystalline epoxy compounds in the composition is not particularly limited. However, in order to maintain the liquid crystallinity of the composition, the content of the liquid crystalline epoxy compound is preferably 50 mol % or more with respect to the entire epoxy compound.

Two or more liquid crystalline epoxy compounds may be used in combination.

"Chiral compound"
As the chiral compound used in the present invention, known compounds can be used without particular limitation. However, compounds with functional groups such as oxiranyl or amino, phenol and its derivatives are preferred as they do not reduce the heat resistance of the material.
Moreover, in the present invention, the epoxy compound may be a chiral compound.

The structure of the chiral compound is also not particularly limited. However, isosorbide and binaphthyl structures are preferred because they have a large helical twist power (HTP) to liquid crystals and are readily available. Further, the isosorbide structure is more preferable because of its high compatibility with the composition.

Preferred examples of such a chiral compound include compounds represented by the following formulas (CL-1) to (CL-23).

式中、Ｒ^１０は炭素数１から８のアルキルを表し、芳香環上で繋がっていない置換基は、置換位置が任意であることを表す。また、それぞれの芳香環の少なくとも１つの水素は、メチル、メトキシ、またはＯＨで置換されてもよい。

In the formula, R ¹⁰ represents alkyl having 1 to 8 carbon atoms, and substituents not connected on the aromatic ring represent arbitrary substitution positions. Also, at least one hydrogen of each aromatic ring may be replaced with methyl, methoxy, or OH.

Among the chiral compounds represented by the above formulas (CL-1) to (CL-23), since they are highly compatible with other starting compounds, formulas (CL-1) to (CL-11) Chiral compounds represented by the formula (CL-1), formula (CL-5), formula (CL-7), formula (CL-9) to formula (CL-11) are preferred chiral compounds represented by More preferred.

When using a liquid crystalline epoxy compound, it is preferable to use a chiral compound having a substituent other than oxiranyl in order to prevent deterioration of the liquid crystallinity of the composition. Among them, the chiral compounds represented by the formulas (CL-1), (CL-5), and (CL-7) are preferred because of their high compatibility with other starting compounds.

Among these chiral compounds, the compound represented by formula (CL-1) is most preferable because it is easy to produce.

The content of these chiral compounds in the composition of the present invention is not particularly limited. However, in order for the composition to exhibit a blue phase, when the chiral compound does not have liquid crystallinity, the content is preferably from 10 to 50 mol% with respect to the total number of moles of the raw material compound of the epoxy resin. A content of up to 30 mol % is more preferred. In addition, when the chiral compound has liquid crystallinity, the content is preferably 10 to 100 mol % with respect to the number of moles of the entire raw material compound of the epoxy resin.

Two or more chiral compounds may be used in combination.

式（２）中、ＣＧは、独立して、ＯＨ、ＯＣＯＲ^１０、ＯＣＮ、またはＮＨ_２であり、このときＲ^１０は、炭素数１から８のアルキルであり、Ｘは、独立して、単結合、－ＣＨ_２ＣＨ_２－、－ＣＨ_２Ｏ－、－ＣＨ＝ＣＨ－、－Ｃ≡Ｃ－、－ＯＣＯ－、または－ＣＯＯ－であり、Ｒ^１は、独立して、水素、ＯＨ、炭素数１から８のアルキル、炭素数１から８のアルコキシ、または炭素数２から８のアルケニルであり、これらアルキル、アルコキシ、およびアルケニルの１つの－ＣＨ_２－は－ＣＯ－で置換していても良く、ｎは０から２である。 "Hardener"
The curing agent that can be used in the composition of the present invention is not limited, and known epoxy curing agents can be used. Among them, it is preferable to select a compound represented by the following formula (2) because of its excellent compatibility with other raw material compounds, particularly liquid crystalline epoxy compounds.

In formula (2), CG is independently OH, OCOR ¹⁰ , OCN, or NH ₂ , where R ¹⁰ is alkyl having 1 to 8 carbon atoms, and X is independently a single a bond, —CH ₂ CH ₂ —, —CH ₂ O—, —CH═CH—, —C≡C—, —OCO—, or —COO—, and R ¹ is independently hydrogen, OH, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, or alkenyl having 2 to 8 carbon atoms, wherein one —CH ₂ — of these alkyl, alkoxy or alkenyl is substituted with —CO— is also good, and n is 0 to 2.

式（２－１）から式（２－１０）中、ＣＧは、独立して、ＯＨ、ＯＣＯＲ^１０、ＯＣＮ、またはＮＨ_２であり、このときＲ^１０は、炭素数１から８のアルキルであり、Ｒ^１は、独立して、水素、ＯＨ、炭素数１から８のアルキル、炭素数１から８のアルコキシ、または炭素数２から８のアルケニルであり、これらアルキル、アルコキシ、およびアルケニルの１つの－ＣＨ_２－は－ＣＯ－で置換していても良い。 In the curing agent represented by formula (2), since it has excellent compatibility with other raw material compounds and is easily available, compounds represented by the following formulas (2-1) to (2-10) is preferred.

In formulas (2-1) to (2-10), CG is independently OH, OCOR ¹⁰ , OCN, or NH ₂ , where R ¹⁰ is alkyl having 1 to 8 carbon atoms , R ¹ are independently hydrogen, OH, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, or alkenyl having 2 to 8 carbon atoms, and one of these alkyl, alkoxy and alkenyl —CH ₂ — may be substituted with —CO—.

The compositions of the present invention may be free of curing agents. In that case, a composition consisting only of an epoxy compound can be cured using a cation generator or an anion generator, which will be described later.

"Non-liquid crystalline epoxy compounds"
As long as the liquid crystallinity of the composition is not lost, in addition to the raw material compounds that can be suitably used as described above, known non-liquid crystalline epoxy compounds and other curing agents other than formula (2) can be used in combination. .

As known non-liquid crystalline epoxy compounds, compounds represented by formulas (o-1) to (o-15) are preferably used.

In formula (o-6), Z ¹⁰ is a single bond, —CH ₂ —, —O—, —S—, —CH(CH ₃ )—, —C(CH ₃ ) ₂ —, —SO ₂ —, or —C(CF ₃ ) ₂ —.

In formulas (o-7) and (o-8), Z ¹¹ is >CH- or >C(CH ₃ )-.

Resins composed of compounds represented by formulas (o-20) to (o-24) are also preferably used as epoxy compounds other than those described above.

In formula (o-20), Z ¹² and Z ¹³ are independently a single bond, -CH ₂ -, -O-, -S-, -CH(CH ₃ )-, -C(CH ₃ ) ₂ - , -SO ₂ -, or -C(CF ₃ ) ₂ -, and n21 is an integer of 1 or more and 5,000 or less.
In formulas (o-21) and (o-22), n21 is an integer of 1 or more and 5000 or less. n22 and n23 are independently 0 or 1, and when n21 is 2 or more, it may be different for each repetition.
R ¹⁰ and R ¹¹ are 1,4-phenylene, 4,4'-biphenylene, or cyclopentadienylene.
In formulas (o-20) to (o-22), at least one hydrogen on each aromatic ring may be replaced with methyl.

In formulas (o-23) and (o-24), Z ¹⁴ is independently a single bond, —CH(CH ₃ )—, or —C(CH ₃ ) ₂ —, and n21 is 1 or more and 5000 It is an integer below.
In formulas (o-23) and (o-24), at least one hydrogen on each aromatic ring may be replaced with methyl.

The content of such a non-liquid crystalline epoxy compound in the composition of the present invention is not particularly limited as long as the composition or its cured product exhibits desired properties. However, in order to exhibit the effects of the present invention, the content of these non-liquid crystalline epoxy compounds is preferably 50 mol % or less, more preferably 30 mol % or less, based on the total epoxy compounds in the composition.

[Other curing agents]
A curing agent other than the formula (2) may be used in the composition of the present invention as long as it does not degrade the properties such as compatibility. Such curing agents include all known phenols, phenol esters, cyanate esters, amines, carboxylic acids, carboxylic acid esters, anhydrides, or thiol compounds. At this time, it is preferable to use a phenol-based or cyanate ester-based curing agent in order to suppress curing of the composition at room temperature and improve storage stability.

The phenolic curing agent is preferably at least one compound represented by the following formulas (p-1) to (p-7) because it is readily available without significantly impairing the liquid crystallinity of the composition. .

In formula (p-1), n31 is an integer of 2 to 4;
Ring B is benzene, naphthalene, anthracene, fluorene, or 9,9-diphenylfluorene, and in these rings B, at least one hydrogen is replaced with alkyl having 1 to 3 carbon atoms or alkoxy having 1 to 3 carbon atoms. may be However, in benzene, the OH group is never positioned at the p-position.
In formula (p-2), n32 and n33 are independently integers of 1 to 3;
Z ³⁰ is —CH ₂ —, alkylene having 3 to 10 carbon atoms, —CH(CH ₃ )—, —C(CH ₃ ) ₂ —, —C(CF ₃ ) ₂ —, —O—, —S— , -SO ₂ -,
At least one hydrogen on the benzene ring may be replaced with alkyl having 1 to 3 carbon atoms.
In formula (p-3) and formula (p-4), n34 is an integer of 1 or more and 5000 or less, n35 and n36 are independently 0 or 1, and when n34 is 2 or more, each repetition can be different.
In formula (p-4), R ¹⁰ and R ¹¹ are 1,4-phenylene, 4,4'-biphenylene, cyclopentadienylene,
In formula (p-5), n34 is an integer of 1 or more and 5000 or less,
In formula (p-6), n34 is an integer of 1 or more and 5000 or less,
Z ³¹ is independently a single bond, —CH(CH ₃ )—, or —C(CH ₃ ) ₂ —, and n34 is an integer of 1 or more and 5,000 or less.
In formula (p-7), n34 is an integer of 1 or more and 5000 or less, and ^R12 is hydrogen or methyl.
In formulas (p-3) to (p-7), at least one hydrogen on each aromatic ring may be replaced with methyl.

The amine-based curing agent is preferably at least one compound represented by the following formula (a-1) or (a-2) because it is readily available without significantly impairing the liquid crystallinity of the composition. .
E ¹ -Z-(LZ)nE ¹ (a-1)
L ¹ -ZE (a-2)

In formulas (a-1) and (a-2),
Z is independently a single bond, —O—, —NH—, —S—, —SO ₂ —, —CO ₂ —, or alkylene having 1 to 12 carbon atoms;
In formula (a-1),
E ¹ is independently amino, alkylamino having 1 to 10 carbon atoms, hydroxyl group, or carboxy; at least one E is amino or alkylamino having 1 to 10 carbon atoms;
L is independently a single bond, cyclohexylene, phenylene, or naphthalene, and at least one hydrogen in these rings may be replaced with alkyl having 1 to 10 carbon atoms;
n is an integer from 0 to 7;
However, the structure represented by Formula (2) is excluded.
In formula (a-2),
L ¹ is hydrogen, cyclohexyl, phenyl, or naphthyl, at least one hydrogen of these rings may be replaced with alkyl having 1 to 10 carbon atoms,
E is amino or alkylamino having 1 to 10 carbon atoms.

Compounds represented by formula (a-1) include ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, p-xylenediamine, m-xylenediamine, and the like. -12 aliphatic polyhydric amines, m-phenylenediamine, N-methyl-p-phenylenediamine, N-ethyl-p-phenylenediamine, N-propyl-p-phenylenediamine, N-butyl-p-phenylenediamine, m-phenylenediamine, N-methyl-m-phenylenediamine, N-ethyl-m-phenylenediamine, N-propyl-m-phenylenediamine, N-butyl-m-phenylenediamine, 2,4-diaminotoluene, 2, 6-diaminotoluene, o-phenylenediamine, 1,5-diaminonaphthalene, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 1,1-bis(4- Aromatic polyvalent amines such as aminophenyl)cyclohexane, 4,4′-diaminodiphenylsulfone, bis(4-aminophenyl)phenylmethane, 1,4-cyclohexyldiamine, 1,3-cyclohexyldiamine, 1,2- Cycloaliphatic polyvalent amines such as cyclohexyldiamine, 1,3-bis(aminomethyl)cyclohexane, and the like.

Among these, N-methyl-p-phenylenediamine, N-ethyl-p-phenylenediamine, N-propyl-p-phenylenediamine, N-propyl-p-phenylenediamine, N-methyl-p-phenylenediamine, N-ethyl-p-phenylenediamine, N-butyl-p-phenylenediamine, 2,5-diaminotoluene, m-phenylenediamine, N-methyl-m-phenylenediamine, N-ethyl-m-phenylenediamine, N-propyl-m-phenylenediamine, N- butyl-m-phenylenediamine, 2,4-diaminotoluene, 2,6-diaminotoluene, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, and 4,4 '-Diaminodiphenyl sulfone is particularly preferred.

Compounds represented by formula (a-2) are fatty acids having 2 to 12 carbon atoms such as n-propylamine, n-butylamine, n-pentylamine, n-hexylamine, n-octylamine and n-dodecylamine. group amines, aniline, o-toluidine, m-toluidine, p-toluidine, 2,3-dimethylaniline, 2,4-dimethylaniline, 2,6-dimethylaniline, 2,4,6-trimethylaniline, 2-ethyl Aromatic amines such as aniline, 1-naphthylamine and 1-amino-2-methylnaphthalene, and alicyclic amines such as cyclohexylamine and 2-methylcyclohexylamine. Among these, aniline, o-toluidine, m-toluidine, p-toluidine, 2,3-dimethylaniline, and 2,4-dimethylaniline have good compatibility when made into a composition and are excellent in storage stability. , 2,6-dimethylaniline, 2,4,6-trimethylaniline, 2-ethylaniline are particularly preferred.

Preferred carboxy-containing curing agents are phthalic acid, terephthalic acid, isophthalic acid, 1,4-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,2′-biphenyldicarboxylic acid, 4 ,4′-biphenyldicarboxylic acid, benzophenone-4,4′-dicarboxylic acid and the like.

The content of such a known curing agent in the composition of the present invention is not particularly limited as long as the composition or its cured product exhibits desired properties. At this time, in order to exhibit the effect of the present invention, it is preferably used in an amount of 60% by weight or less, more preferably 50% by weight or less, and more preferably 40% by weight or less based on the total amount of the curing agent. is most preferred.

In the composition of the present invention, the ratio of epoxy compound to curing agent is not particularly limited. At this time, in order to improve the heat resistance and to proceed the reaction efficiently, it is preferable to make the reactive groups of the epoxy compound and the curing agent equivalent. For example, epoxy:phenol is 1:1 and epoxy:amine is 2:1.

[Curing accelerator]
The composition of the present invention preferably further contains a curing accelerator in order to improve heat resistance. Such curing accelerators include imidazole, 2-methylimidazole, 2-ethyl-4-methyl-1H-imidazole, 2-phenyl-4-methyl-1H-imidazole, 1,2-dimethylimidazole, 2-undecyl. imidazole curing accelerators such as imidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, and 1-cyanoethyl-2-ethyl-4-methylimidazole; phosphorus-based curing accelerators such as triphenylphosphine Curing accelerator, 2,4,6-tris(dimethylaminomethyl)phenol, triethylenediamine, benzyldimethylamine, 2-(dimethylaminomethyl)phenol, 1,8-diazabicyclo[5.4.0]undeca-7- ene, amine curing accelerators such as 4-dimethylaminopyridine, tetraalkylammonium salts and the like. Among such curing accelerators, it is preferable to use an imidazole-based curing accelerator, since the curing temperature is 200° C. or less and the curability is high.

The concentration of the curing accelerator in the composition of the present invention is 0.1 weight with respect to the weight of the polymerizable compound contained in the composition of the present invention in order to improve the heat resistance and to proceed the reaction efficiently. % or more, more preferably 0.5% by weight or more. In order to avoid degradation of reliability due to sublimation of the curing accelerator, the amount is preferably 5% by weight or less, more preferably 3% by weight or less, based on the weight of the polymerizable compound of the present invention.

[Inorganic filler]
The composition for electronic parts of the present invention may contain an inorganic filler.
Inorganic fillers contained in the electronic component composition include nitrides such as aluminum nitride, boron nitride, and silicon nitride as fillers with high thermal conductivity. diamond, graphite, silicon carbide, silicon, beryllia, magnesium oxide, aluminum oxide, zinc oxide, silicon oxide, copper oxide, titanium oxide, cerium oxide, yttrium oxide, tin oxide, forminium oxide, bismuth oxide, cobalt oxide, calcium oxide, Inorganic fillers and metallic fillers such as aluminum nitride, boron nitride, silicon nitride, magnesium hydroxide, aluminum hydroxide, gold, silver, copper, platinum, iron, tin, lead, nickel, aluminum, magnesium, tungsten, molybdenum, and stainless steel It can be material. Boron nitride, aluminum nitride and aluminum oxide are preferred. Boron nitride and aluminum nitride are preferable because they have very high thermal conductivity in the planar direction, low dielectric constant, and high insulating properties. In particular, hexagonal boron nitride (h-BN) and aluminum nitride are preferred.

Examples of the shape of the inorganic filler include spherical, amorphous, fibrous, rod-like, cylindrical, plate-like, and tetrapod-like. The type, shape, size, addition amount, etc. of the inorganic filler can be appropriately selected according to the purpose. For example, when a cured product (material for electronic parts) formed from a composition for electronic parts requires insulation, a conductive inorganic filler may be used as long as the desired insulation is maintained.

The average particle size of the inorganic filler is preferably 0.1 to 200 μm, for example. More preferably, it is 1 to 100 μm. When it is 0.1 μm or more, the thermal conductivity is good, and when it is 200 μm or less, the filling rate can be increased. The average particle size used herein is based on particle size distribution measurement by a laser diffraction/scattering method. That is, using the analysis based on Fraunhofer diffraction theory and Mie's scattering theory, when the powder is divided into two from a certain particle size by the wet method, the larger side and the smaller side are equal (volume basis). was taken as the median diameter.

The amount of the inorganic filler to be added is preferably 20 to 95% by weight with respect to the total amount of non-volatile matter in the composition for electronic parts, for example, when it is used for a heat dissipating member. More preferably, it is 50 to 95% by weight. A content of 20% by weight or more is preferable because the thermal conductivity increases. In order to prevent the material from becoming brittle, the amount of inorganic filler added is preferably 95% by weight or less, more preferably 90% by weight or less.

An unmodified inorganic filler may be used as it is. Alternatively, one whose surface is treated with a coupling agent may be used. For example, boron nitride (h-BN) is treated with a silane coupling agent. In the case of boron nitride, since there are no reactive groups on the plane of the particles, the silane coupling agent is bonded only to the periphery thereof. Boron nitride treated with a coupling agent can form bonds with polymerizable compounds in the electronic component composition, which bonds are believed to contribute to heat conduction. Therefore, the coupling agent is preferably oxiranyl, oxetanyl, or one that reacts with the group possessed by the curing agent. For example, amines, or those having oxiranyl or oxetanyl are preferred. Specifically, Sila Ace S310, S320, S330, S360, S510, S530, etc., manufactured by JNC Co., Ltd. can be mentioned.

The inorganic filler may be treated with a coupling agent and then surface-modified with a compound having a polymerizable group such as epoxy (polymerizable compound). For example, boron nitride (h-BN) treated with a silane coupling agent is surface-modified with a polymerizable compound. If the boron nitride surface-modified with a polymerizable compound can form a bond with the polymerizable compound or curing agent in the composition for electronic components, this bond is believed to contribute to heat conduction. For example, the polymerizable compound may be a compound represented by formula (1) or other polymerizable compounds.

[Other components]
Other constituents that can be contained in the composition of the present invention are not particularly limited. Examples thereof include polymerizable compounds having a polymerizable group other than epoxy, non-polymerizable compounds, polymerization initiators, and solvents.

The polymerizable compound having a polymerizable group other than epoxy is not particularly limited as long as it does not deteriorate the properties of the electronic material of the present invention, and known polymerizable compounds can be used. Among them, radically polymerizable compounds such as acrylic compounds and styrene compounds can be preferably used, and those compounds having liquid crystallinity can be used more preferably.
Polymerization initiators include, for example, thermal polymerization initiators, photocationic polymerization initiators, and photoanion polymerization initiators. Thermal cationic polymerization initiators include sulfonium salts, boron trifluoride-amine complexes, dicyanazides, organic acid hydrazides, and toluenesulfonic acid esters. Sulfonium salt-based, iodonium salt-based, and nonionic photo-cationic initiators are known. Furthermore, known photoanionic initiators include oxime-based, carbamate-based, guanidinium-carboxylate-based, and nifedipine-based initiators.

When the composition of the present invention contains a radically polymerizable compound such as an acrylic compound or a styrenic compound, a radical polymerization initiator may be used.

The composition of the invention may contain a solvent. The composition may be polymerized in a solvent or without a solvent. Preferred solvents are, for example, 1,4-dioxane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, Propylene glycol monomethyl ether, propylene glycol monobutyl ether, 3-methoxy-3-methyl-1-butanol, dipropylene glycol methyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, N -methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, diethyl carbonate, ethyl methyl carbonate , γ-butyrolactone, methyl lactate, ethyl lactate, butyl lactate, 2-ethylhexanol, 1-propanol, isobutyl alcohol, n-butanol, 2-pentanone, methyl isobutyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, diacetone alcohol , ethylene glycol. A solvent may be used individually by 1 type, or may be used in mixture of 2 or more types.

Since the composition of the present invention has high polymerizability, a stabilizer may be added to facilitate handling. Any known stabilizer can be used without limitation. Examples include hydroquinone, 4-ethoxyphenol, and 3,5-di-t-butyl-4-hydroxytoluene (BHT).

Furthermore, additives (such as oxides) may be added to adjust the viscosity and color of the composition for electronic parts. For example, titanium oxide for whitening, carbon black for blackening, and silica fine powder for adjusting viscosity can be used. In addition, in order to further increase the mechanical strength, for example, inorganic fibers such as glass and carbon fibers, their cloths, synthetic fibers such as polyvinyl formal, polyvinyl butyral, polyester, polyamide, polyimide, or supramolecules are used. may be added.

[Materials for electronic parts]
The electronic component material of the present invention is obtained by molding a cured product obtained by curing the electronic component composition according to the second embodiment according to the application. For example, an electronic component material can be applied as a heat dissipation member.

The electronic component material is a polymer (epoxy resin) obtained by polymerizing (curing) the composition of the present invention. This polymer has high thermal conductivity and is excellent in chemical stability, heat resistance, hardness, mechanical strength, and the like. The mechanical strength includes Young's modulus, tensile strength, tearing strength, bending strength, bending elastic modulus, impact strength, and the like.

The composition of the invention is a thermosetting resin. A thermosetting resin is cured by heating a composition as a raw material to polymerize a monomer contained in the composition, and further three-dimensionally crosslink the composition. The heating temperature at this time is preferably within a temperature range in which the composition of the present invention exhibits a liquid crystal phase (blue phase). Further, the liquid crystal temperature range of the composition of the present invention may be increased by proceeding with curing to some extent. In such cases, it may be cured in an elevated liquid crystal temperature range.

The cured product of the present invention is considered to contain a double-twisted cylinder structure derived from the blue phase. Due to such a characteristic structure, the cured product of the present invention has properties such as high thermal conductivity.

The curing temperature may be constant, or may be increased or decreased stepwise. In the latter case, the initial curing temperature is preferably a temperature at which the composition or its cured product exhibits a liquid crystal phase, in order to improve the heat dissipation properties of the material. Moreover, in order to improve heat resistance, it is preferable to heat at a temperature higher than the initial curing temperature. In the case of stepwise curing at different temperatures, in order to shorten the production time of the cured product, it is preferable to cure using a plurality of heating devices having constant and different temperatures.

The thermosetting temperature by thermal polymerization is in the range of 20°C to 350°C, preferably 20°C to 250°C, more preferably 50°C to 200°C. Curing times range from 5 seconds to 10 hours, preferably from 1 minute to 8 hours, more preferably from 5 minutes to 5 hours. After polymerization, slow cooling is preferable in order to suppress stress strain and the like. In addition, reheating treatment may be performed to relax strain and the like.

A cross-linking agent may be added for better cross-linking. Thereby, a polymer (cured product) having extremely excellent chemical resistance and heat resistance can be obtained. As such a cross-linking agent, known ones can be used without limitation, and examples thereof include trimethylolpropane tris (3-mercaptopropionate).

The electronic component material of the present invention can be used in the form of sheets, films, thin films, fibers, moldings, and the like. Preferred shapes are films and thin films. Films and thin films are obtained by polymerizing a composition for electronic parts in a state of being coated on a substrate or sandwiched between substrates. It can also be obtained by applying a solvent-containing composition for electronic parts to a substrate and removing the solvent. Films can also be obtained by press molding of polymers. In this specification, the thickness of the sheet is 1 mm or more, the thickness of the film is 5 μm or more, preferably 10 to 900 μm, more preferably 20 to 800 μm, and the thickness of the thin film is less than 5 μm. . The film thickness may be appropriately changed depending on the application.

The electronic component material of the present invention has excellent properties such as chemical stability, heat resistance, hardness and mechanical strength in addition to high thermal conductivity. Therefore, it is useful for heat radiation plates, heat radiation sheets, heat radiation films, heat radiation coatings, heat radiation adhesives, heat radiation moldings, and the like.

Although the use of the electronic component material formed from the composition of the present invention as a heat dissipation material has been described above, the application of the electronic component material is not limited to the heat dissipation material. For example, it may be used as a sealing material or an adhesive material.

[Method for producing composition for electronic parts]
The electronic component composition refers to a material that is the composition of the present invention, and may contain an inorganic filler to increase thermal conductivity, and the inorganic filler may or may not be subjected to a coupling treatment. As an example of producing a composition for electronic parts, a production method in which an inorganic filler is subjected to a coupling treatment will be described. A known method can be applied to the coupling treatment.

As an example, the inorganic filler particles and the coupling agent are first added to the solvent. After stirring with a stirrer or the like, leave to stand. After drying the solvent, heat treatment is performed under vacuum conditions using a vacuum dryer or the like. A solvent is added to the inorganic filler particles, and the particles are pulverized by ultrasonic treatment. This solution is separated and purified using a centrifuge. After discarding the supernatant, the solvent is added and the same operation is repeated several times. An oven is used to dry the inorganic filler particles after purification.

Next, the coupling-treated inorganic filler particles and the polymerizable compound are mixed using an agate mortar or the like, and then kneaded using a twin-screw roll or the like. Then, it is separated and purified by ultrasonic treatment and centrifugation.

Further, an amine-based curing agent is added, mixed using an agate mortar or the like, and then kneaded using a twin-screw roll or the like. Thereby, a solvent-free composition for electronic parts is obtained.

[Method for producing electronic component material]
As an example, a method for producing a film as a material for electronic parts using a solvent-free composition for electronic parts will be described.

A solvent-free composition for electronic components is sandwiched between hot plates using a compression molding machine and molded by compression molding. A polymerizable compound is polymerized at a predetermined temperature and time to form a polymer. Further, post-curing may be performed at an appropriate time and temperature. The pressure during compression molding is preferably 50-500 kgf/cm ² , more preferably 70-250 kgf/cm ² . Basically, the higher the pressure during curing, the better. However, it is preferable to apply an appropriate pressure by appropriately changing the fluidity of the mold and the desired physical properties (such as which direction of thermal conductivity is emphasized).

When the composition for electronic parts is in a partially cured state (semi-cured state), it becomes easier to handle. For example, the semi-cured composition may be formed into a sheet, cut into a desired shape, placed between suitable members, and bonded together.

A method for producing a film as a material for electronic parts using a composition for electronic parts containing a solvent will be described.

A composition for electronic parts is applied onto a substrate, and the solvent is removed by drying to form a coating layer having a uniform thickness. Examples of coating methods include spin coating, roll coating, caten coating, flow coating, printing, micro gravure coating, gravure coating, wire bar coating, slit coating, dip coating, spray coating, and meniscus coating.

Drying removal of the solvent can be carried out, for example, by air drying at room temperature, drying on a hot plate, drying on a drying oven, blowing warm air or hot air, or the like. Conditions for removing the solvent are not particularly limited, and drying may be performed until most of the solvent is removed and the fluidity of the coating film layer is lost.

[Electronic parts]
An electronic component includes, for example, an electronic device having a heat generating portion. When the electronic component material of the present invention is used as a heat radiating member, the heat radiating member is arranged in the electronic device so as to be in contact with the heat generating portion. The shape of the heat dissipating member may be any of a heat dissipating plate, a heat dissipating sheet, a heat dissipating film, a heat dissipating adhesive, a heat dissipating molded article, and the like. In this way, the heat generated in the electronic device is dissipated by the heat dissipating member, so that failure due to heat can be avoided and the life of the electronic equipment including the electronic device can be extended.

An example of an electronic device is a semiconductor element. The heat dissipation member has high heat resistance and high insulation in addition to high thermal conductivity. Therefore, it is particularly effective for an insulated gate bipolar transistor (IGBT), which requires a more efficient heat dissipation mechanism due to its high power among semiconductor devices. An IGBT is one of semiconductor elements, and is a bipolar transistor with a MOSFET incorporated in its gate, and is used for power control. Electronic devices equipped with IGBTs include main conversion elements of large power inverters, uninterruptible power supplies, variable voltage variable frequency control devices for AC motors, control devices for railway vehicles, electric transportation equipment such as hybrid cars and electric cars, and IH. cooking utensils and the like.

[Method for Synthesizing Compounds Represented by Formula (1) and Formula (2) and Chiral Compounds]
The compounds represented by formulas (1) and (2) and the chiral compound can be synthesized by combining known techniques in synthetic organic chemistry. Methods for introducing the desired polymerizable group and ring structure into the starting material include, for example, Houben-Weyl, Methods of Organic Chemistry, Georg Thieme Verlag, Stuttgart, Organic Syntheses, John Wiley & Sons, Inc.), Organic Reactions (John Wiley & Sons, Inc.), Comprehensive Organic Synthesis (Pergamon Press), Shin Jikken Kagaku Koza (Maruzen), etc. Are listed. Also, Japanese Patent Application Laid-Open No. 2006-265527 may be referred to. Furthermore, a part is disclosed also in an Example.

Hereinafter, the present invention will be described in detail using examples. However, the invention is not limited to what is described in the examples. Measurements were performed at 23° C. unless the temperature was described.

[NMR measurement]
NMR was measured by VARIAN NMR SYSTEM manufactured by VARIAN. The magnetic field strength in the ¹ H NMR measurements was 500 MHz, the samples were dissolved in deuterated solvents such as CDCl ₃ , and the measurements were performed at room temperature. At this time, the number of integration times is eight. The internal standard is tetramethylsilane. Among the NMR codes, s means singlet, d doublet, t triplet, m multiplet, and br broad.

[Confirmation of blue phase]
A polarizing microscope (manufactured by Nikon Corporation) with a hot stage (manufactured by Mettler Toledo Corporation) was used. The composition was dropped onto a glass slide and heated at 80° C. for 2 minutes to evaporate the solvent. The composition was then heated to the isotropic phase and cooled to observe the phase change. The temperature drop rate was measured at 3°C/min.
Identification of the blue phase was performed as follows. That is, in the vicinity of the temperature at which the isotropic phase transitions to the liquid crystal phase, when the angle of polarization of the upper and lower polarizing plates is about 80 degrees, a coloring phenomenon is observed due to the optical rotation of the sample, and the angle of polarization is changed to A blue phase was defined as a state in which the field of view was dark when set to 90 degrees.

[Measurement of thermal conductivity]
The thermal diffusivity in the thickness direction of the sample was measured using an ai-Phase Mobile 1u thermal diffusivity measuring device manufactured by i-Phase Co., Ltd. From the specific heat (c, J/(Kg)) and density (ρ, g/m ³ ) of the sample, the thermal conductivity (W/(Km)) was obtained according to the following formula.
κ=α×c×ρ
At this time, the specific heat was measured with a DSC-type high-sensitivity differential scanning calorimeter Thermo Plus EVO2 DSC-8231 manufactured by Rigaku Corporation. The specific gravity was measured with a specific gravity meter DME-220 manufactured by Shinko Denshi Co., Ltd.

[Epoxy compound and curing agent]
As epoxy compounds represented by formula (1), compounds represented by the following formulas (1-9-1), (1-10-1), and (1-10-2) are used in Examples. bottom. These compounds were synthesized according to Synthesis Example 1 and Japanese Patent Application No. 2021-083058.
As a chiral compound, a phenol derivative represented by (CL-1-1) below was used in Examples. This compound was synthesized as described in Example 1.
Compounds represented by the following formulas (2-2-1) and (2-2-2) were used as curing agents. A compound represented by formula (2-2-1) was synthesized according to Japanese Patent Application No. 2021-097293. The compound represented by formula (2-2-2) is described in European Journal of Medicinal Chemistry, 46, 488 (2011). Synthesized according to

[Curing accelerator]
Curesol SIZ (manufactured by Shikoku Kasei Kogyo Co., Ltd.), which is an imidazole-based curing accelerator, was used as it was without purification.

市販の４－ブロモ－３－メチルフェノール １０．０ｇ（５３．５ｍｍｏｌ）、６－ブロモ－１－ヘキセン ９．２０ｇ（５６．４ｍｍｏｌ）、およびＫ_２ＣＯ_３ ９．３０ｇ（６７．３ｍｍｏｌ）の混合物を、メチルエチルケトン（１００ｍｌ）中、２０時間還流した。反応液を冷却後、純水（１００ｍｌ）およびトルエン（１００ｍｌ）を加え、分液操作を行った。有機層を無水ＭｇＳＯ_４で乾燥後、ろ過し、溶媒を減圧留去した。残渣をカラムクロマトグラフィー（シリカゲル、トルエン）で精製することにより、４－（５－ヘキセニルオキシ）－２－メチルブロモベンゼンを得た。収量１４．２ｇ（収率９９％）。 [Synthesis Example 1]
Synthesis of compound represented by formula (1-9-1)

A mixture of 10.0 g (53.5 mmol) of commercially available 4-bromo-3-methylphenol, 9.20 g (56.4 mmol) of 6-bromo-1-hexene, and 9.30 g (67.3 mmol) of K ₂ CO ₃ was refluxed in methyl ethyl ketone (100 ml) for 20 hours. After cooling the reaction solution, pure water (100 ml) and toluene (100 ml) were added to separate the layers. After drying the organic layer over anhydrous MgSO ₄ , it was filtered and the solvent was removed under reduced pressure. The residue was purified by column chromatography (silica gel, toluene) to give 4-(5-hexenyloxy)-2-methylbromobenzene. Yield 14.2 g (99% yield).

According to the method described in Japanese Patent Application No. 2021-083058, 4-(5-hexenyloxy)-2-methylphenylboronic acid was synthesized using the above 4-(5-hexenyloxy)-2-methylbromobenzene. Yield 7.55 g (61% yield).

4-(5-hexenyloxy)-2-methylphenylboronic acid 7.55 g (32.2 mmol), compound (1-9-1-a) 8.00 g (27.8 mmol), tetrakistriphenylphosphine palladium ( A mixture of 880 mg of 0) and 5.72 g (54.0 mmol) of Na ₂ CO ₃ was refluxed for 4 hours in a mixed solvent of THF/pure water=80/80 ml under a nitrogen stream. After cooling the reaction solution, pure water (100 ml) and toluene (100 ml) were added to separate the layers. After drying the organic layer over anhydrous MgSO ₄ , it was filtered and the solvent was removed under reduced pressure. The residue was purified by column chromatography (silica gel, heptane/toluene=10/1→5/1) and recrystallization (ethanol) to obtain compound (1-9-1-b). Yield 9.15 g (83% yield). The above compound (1-9-1-a) was synthesized in the same manner as in EP1013649A.

A compound represented by formula (1-9-1-b) was oxidized using mCPBA. The resulting product was purified by column chromatography (silica gel, toluene/ethyl acetate=20/1) and recrystallization (ethanol) to obtain compound (1-9-1). Yield 8.10 g (82% yield).

Phase transition point (°C); C 66.6 N 102.4 I
¹ H-NMR (ppm, CDCl ₃ ); 7.61, 7.58, 7.37, 7.30 (AA'BB', 8H), 7.20 (d, 1H, J = 8.50 Hz), 6.84 (d, 1H, J = 3.00Hz), 6.80 (dd, 1H, J = 8.00, 2.50Hz), 4.02 (t, 2H, 6.50Hz), 3.05 -2.75, 2.53-2.50 (m, 8H), 2.31 (s, 3H), 2.00-1.82, 1.74-1.50 (m, 8H).

ＮａＨ ２．０ｇ（６０％、５０ｍｍｏｌ）およびテトラブチルアンモニウムヨージド １．５３ｇ（４．１４ｍｍｏｌ）を、窒素雰囲気下、ＤＭＦ（脱水、１６ｍｌ）に分散させた。氷浴上、この混合物に、イソソルビド ３．０３ｇ（２０．７ｍｍｏｌ）のＤＭＦ（３２ｍｌ）溶液を加えた。０～５℃を維持しながら、反応溶液を３０分攪拌した。この温度で、ｐ－アリルオキシベンジルクロリド ８．３５ｇ（４５．７ｍｍｏｌ）を加え、その後室温で６０時間攪拌した。反応液にトルエン（５０ｍｌ）と純水（５０ｍｌ）を加え、分液を行った。有機層を純水（２０ｍｌ）で２回洗浄後、無水ＭｇＳＯ_４で乾燥した。ろ過及び溶媒を減圧留去後、得られた生成物をカラムクロマトグラフィー（トルエン：酢酸エチル＝１０：１）で精製することにより、化合物（ＣＬ－１－１－ａ）を得た。収量６．９０ｇ（収率７６％）。
ｐ－アリルオキシベンジルクロリドは、Ｊｏｕｒｎａｌ ｏｆ Ｏｒｇａｎｉｃ Ｃｈｅｍｉｓｔｒｙ，８５，２７５２（２０２０）に従って、合成した。 [Example 1]
Synthesis of compound represented by formula (CL-1-1)

2.0 g (60%, 50 mmol) NaH and 1.53 g (4.14 mmol) tetrabutylammonium iodide were dispersed in DMF (dry, 16 ml) under a nitrogen atmosphere. A solution of 3.03 g (20.7 mmol) of isosorbide in DMF (32 ml) was added to this mixture on an ice bath. The reaction solution was stirred for 30 minutes while maintaining 0-5°C. At this temperature, 8.35 g (45.7 mmol) of p-allyloxybenzyl chloride was added, followed by stirring at room temperature for 60 hours. Toluene (50 ml) and pure water (50 ml) were added to the reaction liquid to separate the layers. The organic layer was washed twice with pure water (20 ml) and dried over anhydrous _MgSO4 . After filtration and evaporation of the solvent under reduced pressure, the resulting product was purified by column chromatography (toluene:ethyl acetate=10:1) to obtain compound (CL-1-1-a). Yield 6.90 g (76% yield).
p-Allyloxybenzyl chloride was synthesized according to Journal of Organic Chemistry, 85, 2752 (2020).

A mixture of 500 mg (1.14 mmol) of compound (CL-1-1-a), 40 mg (0.057 mmol) of PdCl ₂ (PPh ₃ )2, and 720 mg (11 mmol) of ammonium formate was prepared in THF (10 ml) in a nitrogen atmosphere. It was refluxed for 12 hours. After cooling, ethyl acetate (40 ml) and pure water (20 ml) were added to the reaction mixture to separate the layers. The organic layer was dried over anhydrous _MgSO4 , filtered and the solvent was removed under reduced pressure. The resulting product was purified by column chromatography (toluene:ethyl acetate=2:1) to obtain compound (CL-1-1). Yield 0.29 g (71% yield).

Melting point (°C); 122.5-128.2°C
¹ H-NMR (ppm, CDCl ₃ ); 9.21 (brs, 2H), 7.15-7.09 (m, 4H), 6.74-6.71 (m, 4H), 4.64- 4.35 (m, 6H), 4.08-3.74 (m, 5H), 3.48 (t, 1H, J=8.00Hz).

[Example 2] to [Example 7], [Comparative Example 1] and [Comparative Example 2]
Compositions 2 to 7 containing no curing accelerator were prepared at the mixing ratios shown in Table 1 below. Cyclopentanone was used as the solvent, and the solid concentration was 20 wt %. The numbers in parentheses in the table are mol% of each raw material in the whole raw material compound.

Table 1 Compositions with blue phase

[Example 8]
Measurement of Thermal Conductivity of Cured Material Prepared from Composition 2 A composition (composition 2C) was prepared by adding 1% by weight of CURESOL SIZ to the total solid content of composition 2 above. This composition 2C was placed on a 0.5 cm square PTFE sheet having a depression of 0.2 mm in depth, held for 5 minutes on a hot plate heated to a temperature of 50 ° C., and then heated to a temperature of 115 ° C. It was kept on a heated hot plate for 60 minutes, and a circular piece with a thickness of 0.05 to 0.2 mm was taken out. The thermal conductivity of this cured product (cured product 2C) was 0.58 W/m·K in the thickness direction of the sample.

[Example 9]
A composition (composition 3C) was prepared by adding Cursol SIZ to composition 3 in the same manner as in Example 8, and the thermal conductivity of composition 3C was measured. As a result, it was 0.55 W/m·K in the thickness direction of the sample.

[Comparative Example 3]
A composition (composition R1C) was prepared by adding Cursol SIZ to composition R1 in the same manner as in Example 8, and the thermal conductivity of composition R1C was measured. As a result, it was 0.31 W/m·K in the thickness direction of the sample.

As noted above, the compositions of the present invention are found to provide high thermal conductivity.

The technology of the present invention can be suitably used for packaging materials for semiconductor devices. It can also be used for alternative applications to other epoxy resins such as adhesives.

Claims (13)

A composition containing at least one epoxy compound and at least one chiral compound and having a chiral phase. The composition according to claim 1, wherein the epoxy compound is a rod-shaped liquid crystalline compound. 3. The composition according to claim 2, wherein the epoxy compound is a compound represented by formula (1).

In formula (1), R ^ep is independently a group having 2 to 12 carbon atoms including oxiranyl, non-adjacent CH ₂ may be substituted with O, and X is independently a single a bond, —CH ₂ CH ₂ —, —CH ₂ O—, —CH═CH—, —C≡C—, —OCO—, or —COO—, and R ¹ is independently hydrogen, fluorine, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, alkenyl having 2 to 8 carbon atoms, or R ^ep , wherein one —CH ₂ — of these alkyl, alkoxy or alkenyl is substituted with —CO—; A is 1,4-phenylene, cyclohexane-1,4-diyl, cyclohexene-1,4-diyl, and n is 0 to 2. 2. The composition according to claim 1, wherein the chiral compound is an isosorbide or binaphthyl derivative. A composition according to claim 1, wherein the chiral phase is the blue phase. 6. The composition of any one of claims 1-5, further comprising a curing agent. 7. The composition of Claim 6, wherein at least one of the curing agents is a chiral compound. 8. The composition of any one of claims 1-7, further comprising an inorganic filler. 9. An epoxy resin obtained by curing the composition of any one of claims 1-8. 10. Epoxy resin according to claim 9, wherein the blue phase of the composition is immobilized. An electronic component material using the epoxy resin according to claim 9 or 10. A heat dissipating material obtained from the electronic component material according to claim 11, wherein the self-assembled structure derived from the blue phase includes a structure immobilized by polymerization. A chiral compound represented by formula (CL-1).

In formula (CL-1), at least one hydrogen on each aromatic ring may be replaced with methyl, methoxy, or OH.