JP2022085610A - Composition, and cured product of the same - Google Patents

Abstract

To provide a composition capable of making a cured product having excellent low dielectric characteristics.SOLUTION: A composition includes: an olefin-aromatic vinyl compound-aromatic polyene copolymer; and a polar monomer, where the value in a measured frequency range of 27-42GHz of a dielectric constant of a cured product of the composition found by a resonator method is 2.7 or less, the value in a measured frequency range of 27-42GHz of a dielectric tangent of a cured product of the composition found by a resonator method is 1.5×10-3 or less, and the CTE (coefficient of linear thermal expansion) of the composition found on the basis of a JPCA standard "electronic circuit board standard third edition" Clause 16 "material standard for print circuit board" is 130 ppm/K or less.SELECTED DRAWING: None

Description

The present invention relates to a composition and a cured product thereof.

As the communication frequency shifts to the gigahertz band and higher frequency bands, there is an increasing need for insulating materials having low dielectric properties. Polyolefins such as polyethylene and aromatic vinyl compound polymers such as polystyrene do not have polar groups in their molecular structures, and are therefore known as materials exhibiting excellent low dielectric constant and low dielectric loss tangent. However, since the heat resistance of these depends on the melting point of the crystal or the glass transition temperature, there is a problem in the heat resistance as an electric insulator, and since they are thermoplastic resins, there is a problem in the film forming process (Patent Document 1). ..

Fluorine-based resins such as perfluoroethylene have excellent characteristics of low dielectric constant, low dielectric loss and heat resistance, but molding processing and film forming are difficult and device suitability is low. In addition, there is a problem in the adhesive strength of the wiring with the copper foil. On the other hand, substrates and insulating materials using post-curing resins such as epoxy resins, unsaturated polyester resins, polyimide resins, and phenol resins have been widely used because of their heat resistance and easy handling, but they have a dielectric constant and a dielectric loss. It is relatively expensive, and improvement is desired as an insulating material for high frequencies (Patent Document 2).

A graft composed of olefin-based and styrene-based polymer segments, or an electrically insulating material composed of a block copolymer has been proposed (Patent Document 3). The material focuses on the intrinsically low dielectric constant and low dielectric loss of olefin and styrene-based hydrocarbon polymers. The manufacturing method is to perform general graft polymerization on commercially available polyethylene and polypropylene in the presence of styrene monomer, divinylbenzene monomer and radical polymerization initiator, and such a method does not increase the graft efficiency (crosslink density). , There is a problem that the uniformity of the polymer is not sufficient. Further, the obtained polymer contains a gel, and has a problem of poor processability and filling property. The material is a thermoplastic resin and has insufficient heat resistance, and it is necessary to add a heat resistant resin such as 4-methyl-1-pentene. Therefore, it is difficult to apply the material to a molding method in which the material is applied or filled in a predetermined place and then cured.

Patent Documents 4 to 6 show cured products obtained from a specific polymerization catalyst and composed of an ethylene-olefin (aromatic vinyl compound) -polyene copolymer and a non-polar vinyl compound having a specific composition and composition. Compositions with fillers such as common silica are also described.

Further, it is known that a filler is added when molding a resin sheet, and as such a filler, spherical silica as described in Patent Documents 7 and 8 is also used. However, the effect of the combination of the type of resin and the type of filler has not been sufficiently investigated.

Special Publication No. 52-031272 Japanese Unexamined Patent Publication No. 6-192392 Japanese Unexamined Patent Publication No. 11-060645 Japanese Unexamined Patent Publication No. 2010-280771 Japanese Unexamined Patent Publication No. 2009-161743 Japanese Unexamined Patent Publication No. 2010-280860 Japanese Patent Application Laid-Open No. 2003-165718 Japanese Patent Publication No. 2013-528558

Even if it is a thermoplastic composition that can be easily molded, a cured product having excellent low dielectric properties required for an insulating material for high-frequency signal transmission has been desired. In particular, in the case of electronic substrate applications where a solder reflow process is performed, which involves high temperature exposure, the required aptitude requirements are strict, and the materials that can be used in actual use are limited. Therefore, it has been desired to provide a material having such excellent low dielectric properties.

That is, the present invention can provide the following aspects.

Aspect 1.
Olefin-aromatic vinyl compound-aromatic polyene copolymer and
A composition containing a polar monomer.
The value of the dielectric constant of the cured product of the composition obtained by the resonator method in the measurement frequency range of 27 GHz to 42 GHz is 2.7 or less.
The value of the dielectric loss tangent of the cured product of the composition obtained by the resonator method in the measurement frequency range of 27 GHz to 42 GHz is 1.5 × 10 ^-3 or less.
The CTE (coefficient of linear expansion) of the composition required based on the JPCA standard "Electronic Circuit Board Standard 3rd Edition", Section 16 "Material Standard for Printed Wiring Board" is characterized by being 130 ppm / K or less. The composition.

Aspect 2.
The polar monomer is selected from the group consisting of maleimide, bismaleimide, maleic anhydride, glycidyl (meth) acrylate, triallyl isocyanurate, tri (meth) acrylic isocyanurate, and trimethylolpropane tri (meth) acrylate. The composition according to aspect 1, which is one or more of the above-mentioned compositions.

Aspect 3.
The composition according to aspect 1 or 2, wherein the polar monomer is a bismaleimide having an aromatic ring, and the aromatic ring has one or more groups having 1 or more carbon atoms on the ring.

Aspect 4.
The composition according to any one of aspects 1 to 3, wherein the amount of the polar monomer is in the range of 0.1 to 30 parts by mass with respect to a total of 100 parts by mass of the copolymer and the polar monomer. thing.

Aspect 5.
The copolymer has the following conditions (1) to (4) (1) and the number average molecular weight of the copolymer is 500 or more and 100,000 or less.
(2) The aromatic vinyl compound monomer is an aromatic vinyl compound having 8 or more and 20 or less carbon atoms, and the content of the aromatic vinyl compound monomer unit is 0% by mass or more and 70% by mass or less.
(3) The aromatic polyene is one or more selected from polyenes having a plurality of vinyl groups and / or vinylene groups in the molecule and having 5 or more and 20 or less carbon atoms, and the vinyl group and / or derived from the aromatic polyene unit. The content of vinylene groups is 1.5 or more and less than 20 per number average molecular weight.
(4) The olefin is one or more selected from olefins having 2 or more carbon atoms and 20 or less carbon atoms, and the total of the olefin monomer unit, the aromatic vinyl compound monomer unit and the aromatic polyene monomer unit is 100 mass by mass. %.
The composition according to any one of aspects 1 to 4, wherein all of the above conditions are satisfied.

Aspect 6.
Any of aspects 1 to 5, wherein the value obtained by dividing the storage elastic modulus of the cured product of the composition at 25 ° C. by the storage elastic modulus of the cured product of the composition at 250 ° C. is 20 or less. The composition described in Crab.

Aspect 7.
Further, according to any one of aspects 1 to 6, which comprises a second monomer selected from the group consisting of an aromatic vinyl compound monomer and an aromatic polyene monomer, and / or a resin. Composition.

Aspect 8.
The composition according to aspect 7, wherein the second monomer and / or the resin is contained in an amount of 300 parts by mass or less based on 100 parts by mass of the copolymer.

Aspect 9.
The composition according to any one of aspects 1 to 8, further comprising a curing agent.

Aspect 10.
The composition according to any one of aspects 1 to 9, which is curable.

Aspect 11.
A molded product obtained by curing the composition according to any one of aspects 1 to 10.

Aspect 12.
The molded product according to aspect 11, which is a sheet.

Aspect 13.
The molded product according to aspect 11 or 12, which is an electrically insulating material.

Aspect 14.
A laminate containing a layer containing the composition according to any one of aspects 1 to 10 and a metal foil.

Aspect 15.
A cured product obtained by curing the laminate according to aspect 14.

Aspect 16.
A single-layer CCL, multi-layer CCL, single-layer FCCL, or multi-layer FCCL substrate comprising the cured product according to aspect 15.

The present invention provides a composition in which the cured product (cured product) has excellent low dielectric properties.

The present invention will be described in more detail below. In the present specification, an olefin-aromatic vinyl compound-aromatic polyene copolymer may be simply referred to as a copolymer. Unless otherwise specified, the numerical range in the present specification shall include the upper limit value and the lower limit value. As used herein, the term "sheet" also includes the concept of film. Moreover, even if it is described as a film in this specification, it also includes the concept of a sheet. As used herein, (meth) acrylate is a concept that includes acrylate and methacrylate.

<Composition>
In the present specification, the composition (curable composition) may be referred to as a resin composition or a curable resin composition. The composition of the present invention contains an olefin-aromatic vinyl compound-aromatic polyene copolymer having a certain range of composition and molecular weight range, which will be described later. The composition further comprises a "polar monomer" described below. Further, the present composition contains one or more other components such as "other additive resin components", "inorganic fillers", "monomers other than polar monomers", and "hardeners" described later. May be good.

<Olefin-aromatic vinyl compound-aromatic polyene copolymer>
Examples of a general method for producing an olefin-aromatic vinyl compound-aromatic polyene copolymer that can be used in the present invention are JP-A-2009-161743, JP-A-2010-280771 and International Publication No. 00. It is described in / 37517 and the like. The olefin-aromatic vinyl compound-aromatic polyene copolymer satisfies all of the following conditions (1) to (4).
(1) The number average molecular weight of the copolymer is 500 or more and 100,000 or less, preferably 5,000 or more and 100,000 or less, more preferably 20,000 or more and 100,000 or less, and further preferably 30,000 or more and 100,000 or less.
(2) The aromatic vinyl compound monomer is an aromatic vinyl compound having 8 or more and 20 or less carbon atoms, and the content of the aromatic vinyl compound monomer unit is 0% by mass or more and 70% by mass or less.
(3) The aromatic polyene is one or more selected from polyenes having a plurality of vinyl groups and / or vinylene groups in the molecule and having 5 or more and 20 or less carbon atoms, and the vinyl group and / or derived from the aromatic polyene unit. The content of vinylene groups is 1.5 or more and less than 20 per number average molecular weight, preferably 1.5 or more and less than 7, and more preferably 2 or more and less than 5.
(4) The olefin is one or more selected from olefins having 2 or more carbon atoms and 20 or less carbon atoms, and the total of the olefin monomer unit, the aromatic vinyl compound monomer unit and the aromatic polyene monomer unit is 100 mass by mass. %.

The olefin-aromatic vinyl compound-aromatic polyene copolymer (which may also be abbreviated as "copolymer" in the present specification) is a monomer of an olefin, an aromatic vinyl compound, and an aromatic polyene. Is obtained by copolymerizing.

The olefin monomer is one or more selected from α-olefins having 2 or more and 20 or less carbon atoms and cyclic olefins having 5 or more and 20 or less carbon atoms, and is substantially free of oxygen, nitrogen and halogen, and is composed of carbon and hydrogen. It is a constituent compound. Examples of α-olefins having 2 or more and 20 or less carbon atoms include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decane, 1-dodecane, 4-methyl-1-pentene, 3,5,5. -Trimethyl-1-hexene can be exemplified. Examples of the cyclic olefin having 5 or more and 20 or less carbon atoms include norbornene and cyclopentene. The olefin is preferably a combination of ethylene and an α-olefin or a cyclic olefin other than ethylene, or ethylene alone. When the mass ratio of ethylene alone or α-olefin / ethylene other than ethylene contained is 1/7 or less, more preferably 1/10 or less, the peel strength of the obtained cured product from the copper foil or copper wiring is increased. Can be preferred. More preferably, the content of the α-olefin monomer unit other than ethylene contained in the copolymer is 6% by mass or less, most preferably 4% by mass or less, or the olefin is ethylene alone. In this case, the peel strength from the copper foil or the copper wiring can be further increased, which is more preferable. Further, in a preferable combination of ethylene and an α-olefin other than ethylene, the glass transition temperature of the finally obtained cured product of ethylene-α-olefin-aromatic vinyl compound-aromatic polyene chain depends on the type and content of α-olefin. It can be freely adjusted in the range of -60 ° C to -10 ° C.

The aromatic vinyl compound monomer is an aromatic vinyl compound having 8 or more carbon atoms and 20 or less carbon atoms, and examples thereof include styrene, paramethylstyrene, paraisobutylstyrene, various vinylnaphthalene, and various vinylanthracene.

The aromatic polyene monomer is a polyene having a plurality of vinyl groups and / or vinylene groups in its molecule and having 5 or more and 20 or less carbon atoms, and preferably 8 or more and 20 or less carbon atoms. The aromatic polyene monomer is preferably a polyene having a plurality of vinyl groups in the molecule and having 8 or more carbon atoms and 20 or less carbon atoms, and more preferably various divinylbenzenes of ortho, meta and para, or a mixture thereof, and divinylnaphthalene. , Divinylanthracene, p-2-propenylstyrene, p-3-butenylstyrene, etc. It is a compound having an aromatic vinyl structure, substantially free of oxygen, nitrogen and halogen, and composed of carbon and hydrogen. .. Further, a bifunctional aromatic vinyl compound described in JP-A-2004-087639, for example, 1,2-bis (vinylphenyl) ethane (abbreviation: BVPE) can also be used. Of these, various divinylbenzenes of ortho, meta and para, or mixtures thereof are preferably used, and most preferably a mixture of meta and paradivinylbenzene is used. In this specification, these divinylbenzenes are referred to as divinylbenzenes. When divinylbenzenes are used as the aromatic polyene, it is preferable because the curing efficiency is high and the curing is easy when the curing treatment is performed.

Examples of the above-mentioned olefin, aromatic vinyl compound, and aromatic polyene monomer include an olefin containing a polar group such as an oxygen atom and a nitrogen atom, an aromatic vinyl compound containing an oxygen atom and a nitrogen atom, or an aromatic vinyl compound. , Aromatic polyenes containing oxygen atoms, nitrogen atoms and the like may be contained, but the total mass of the monomers containing these polar groups is preferably 10% by mass or less of the total mass of the present composition, preferably 3% by mass. The following are more preferable, and it is most preferable that the monomer containing a polar group is not contained. By reducing the amount of the monomer to 10% by mass or less, the low dielectric property of the cured product obtained by curing the present composition can be improved (low dielectric constant and low dielectric loss can be set to appropriate values). To be on the safe side, the term "monomer containing a polar group" in this context refers only to the components in the above-mentioned copolymer, and is included in the present composition separately from the copolymer. Please note that it is not a "polar monomer".

The number average molecular weight of this copolymer is 500 or more and 100,000 or less, preferably 5,000 or more and 100,000 or less, more preferably 20,000 or more and 100,000 or less, and further preferably 30,000 or more and 100,000 or less. By setting it in such a range, even if an additional component such as a resin is added in an uncured state, it becomes less sticky, an effect of improving thermoplasticity can be obtained, and further, a high fracture is achieved in the finally obtained cured product. Good physical properties such as point strength and high breaking point elongation can be easily imparted. When the number average molecular weight is 500 or more, the mechanical properties of the composition at the uncured stage are high and the adhesiveness is low, so that the composition can be easily molded as a thermoplastic resin. When the number average molecular weight is 100,000 or less, the moldability is improved. The content of the aromatic vinyl compound monomer unit contained in this copolymer is 0% by mass or more and 70% by mass or less, preferably 0% by mass or more and less than 70% by mass, and more preferably 10% by mass or more and 60% by mass or less. More preferably, it is 10% by mass or more and 55% by mass or less. When the content of the aromatic vinyl compound monomer unit is 70% by mass or less, the glass transition temperature of the cured product of the finally obtained composition does not become around room temperature, and the toughness and elongation at low temperatures are improved. do. When the content of the aromatic vinyl compound monomer unit is 10% by mass or more, the aromaticity of this copolymer is improved, the compatibility with the flame retardant and the filler is improved, and the flame retardant does not bleed out. The effect of easily filling the filler can be obtained. Further, when the content of the aromatic vinyl compound monomer unit is 10% by mass or more, a cured product of a composition having high peel strength from copper foil or copper wiring can be obtained.

In this copolymer, the content of vinyl group and / or vinylene group derived from aromatic polyene unit is 1.5 or more and less than 20 per number average molecular weight, preferably 1.5 or more and less than 7, more preferably. Is 2 or more and less than 5. The content of vinyl group and / or vinylene group may be collectively referred to as "vinyl group content" below. If the vinyl group content is less than 1.5, the cross-linking efficiency is low, and it becomes difficult to obtain a cured product having a sufficient cross-linking density. When the vinyl group content is increased, it becomes easy to improve the mechanical properties of the finally obtained cured product at normal temperature and high temperature. The vinyl group content derived from the aromatic polyene unit per number average molecular weight in this copolymer is the standard polystyrene-equivalent number average molecular weight (Mn) obtained by a GPC (gel permeation chromatography) method known to those skilled in the art. It can be obtained by comparing with the vinyl group content and the vinylene group content derived from the aromatic polyene unit obtained by ¹ H-NMR measurement. As an example, by comparing the intensity of each peak area obtained by ¹ H-NMR measurement, the vinyl group content derived from the aromatic polyene unit in the copolymer was 0.142% by mass, which was converted to standard polystyrene by GPC measurement. When the number average molecular weight is 70927, the molecular weight of the vinyl group derived from the aromatic polyene unit in the number average molecular weight is 100.8, which is the product of these, and by dividing this by the formula weight 27 of the vinyl group, 3 It becomes 0.7. That is, the vinyl group content derived from the aromatic polyene unit per number average molecular weight in this copolymer is 3.7. Attribution of the peak obtained by ¹ H-NMR measurement of the copolymer is known from the literature. Further, a method for obtaining the composition of the copolymer from the comparison of the peak areas obtained by ¹ H-NMR measurement is also known. Further, in the present specification, the content of the divinylbenzene unit in the copolymer is determined from the peak intensity of the vinyl group derived from the divinylbenzene unit (by ¹ H-NMR measurement). That is, from the vinyl group content derived from the divinylbenzene unit, the content of the divinylbenzene unit is determined by assuming that one vinyl group is derived from one divinylbenzene unit in the copolymer.

In the present copolymer, the content of the olefin monomer unit is preferably 30% by mass or more, and particularly preferably 45% by mass or more. The total of the olefin monomer unit, the aromatic vinyl compound monomer unit and the aromatic polyene monomer unit is 100% by mass. When the olefin monomer unit content is 30% by mass or more, the toughness (elongation) of the finally obtained cured product is improved, cracking during curing, deterioration of impact resistance of the cured product, and heat of the cured product are achieved. No cracking occurs during the cycle test. In this copolymer, the preferable olefin monomer unit content is 90% by mass or less.

In this copolymer, as an olefin-aromatic polyene copolymer containing no aromatic vinyl compound monomer unit, specifically, an ethylene-divinylbenzene copolymer, an ethylene-propylene-divinylbenzene copolymer, etc. Ethylene-1-butene-divinylbenzene copolymer, ethylene-1-hexene-divinylbenzene copolymer, and ethylene-1-octene-divinylbenzene copolymer can be exemplified as suitable ones.

In this copolymer, the olefin-aromatic vinyl compound-aromatic polyene copolymer containing the aromatic vinyl compound monomer unit includes an ethylene-styrene-divinylbenzene copolymer and an ethylene-propylene-styrene-divinyl. Examples thereof include a benzene copolymer, an ethylene-1-hexene-styrene-divinylbenzene copolymer, and an ethylene-1-octene-styrene-divinylbenzene copolymer. The copolymer used in the present invention can be produced, for example, by the production method described in International Publication No. 00/37517, JP-A-2009-161743, and JP-A-2010-280771. The amount of the copolymer that may be contained in the present composition can be arbitrarily set according to the intended use. In a preferred embodiment, the amount of the copolymer is 70 to 99.9 parts by mass, more preferably 80 to 99.9 parts by mass, still more preferably, relative to 100 parts by mass of the total of the copolymer and the polar monomer. May be in the range of 85-99.9 parts by mass. By setting the amount of the copolymer in this range, it becomes easy to appropriately control the dielectric constant and the dielectric loss tangent of the obtained cured product.

<Polar monomer>
The polar monomer contained in the composition of the present invention refers to a monomer having polarity in its molecular structure because it has a polar group or the like. With such a polar monomer, it is possible not only to impart adhesiveness to the cured product of the present composition to other materials required as an insulating material, but also to keep both the dielectric constant and the dielectric loss tangent of the cured product low. Become. In general, it is known that the increase / decrease in the permittivity of a certain material and the increase / decrease in the dielectric loss tangent tend to contradict each other. In other words, it has been thought that it is impossible to lower both of them because it is easy for the other to rise if one is lowered. However, the present inventor has found that the crosslink density of the cured product of the composition to which the polar monomer is added is improved, whereby both the dielectric constant and the dielectric loss tangent can be suppressed to a low level, and the present invention is completed. Is. According to the present invention, for example, the dielectric constant is 2.7 or less (more preferably 2.5 or less) and the dielectric loss tangent is 1.5 × 10 ^-3 or less (more preferably 1.2 × 10 ^-3 or less). The remarkable effect of suppressing to is obtained.

Moreover, in the composition containing the polar monomer, the effect that the CTE (linear expansion coefficient) of the cured product can be suppressed to a low level can be obtained. It has been considered difficult to achieve both of these effects in the past, and according to the present invention overturning this, it is possible to provide an extremely useful insulating material.

Examples of the above-mentioned polar monomers include various maleimides, bismaleimides, maleic anhydride, glycidyl (meth) acrylate, triallyl isocyanurate (TAIC), tri (meth) acrylic isocyanurate, and trimethylolpropane tri (meth). ) Acrylate and derivatives thereof and the like can be mentioned. Maleimides and bismaleimides that can be used in the present invention are described in, for example, International Publication No. 2016/114287 and JP-A-2008-291227, and can be purchased from, for example, Daiwa Kasei Kogyo Co., Ltd. and Designer molecules inc Co., Ltd. These maleimide group-containing compounds may be used as polyaminobismaleimide compounds from the viewpoints of solubility in an organic solvent, high frequency characteristics, high adhesiveness to a conductor, moldability of a prepreg, and the like. The polyaminobismaleimide compound is obtained, for example, by carrying out a Michael addition reaction between a compound having two maleimide groups at the terminal and an aromatic diamine compound having two primary amino groups in the molecule. When high cross-linking efficiency is to be obtained with a small amount of addition, polar monomers having a polyfunctional group of two or more functional groups, such as bismaleimides, triallyl isocyanurate (TAIC), and trimethylolpropane tri (meth) acrylate. , And derivatives thereof and the like are preferable.

式中、Ｒ₁、Ｒ₁´はそれぞれ独立に（各々が同一であっても異なっていてもよい）、水素原子又は炭素数1以上（好ましくは炭素数1～20）の置換基であり、そうした置換基としては直鎖又は分鎖のアルキル基（メチル基、エチル基、n-ブチル基、tert-ブチル基、ヘキシル基等）、（メタ）アクリロイル基、アシル基、置換又は非置換のアリール基等が例示できる。また式中のＲ₂は、結合（すなわち、二つの芳香環が直接結合する）であるか、あるいは、炭素数1以上（好ましくは炭素数1～20）の二価リンカー基（例えば直鎖又は分鎖のアルキレン基、エーテル基等）である。好ましくは水素原子以外のＲ₁、Ｒ₁´がこのように芳香環上に複数存在することにより、得られる架橋構造の剛直性が向上し、本発明の効果に資すると考えられる。特定の理論に束縛されることを望むものではないが、そのような芳香環を有するビスマレイミドは単に絶縁性が高いだけではなく、嵩高い置換基の存在によって分子構造が容易に捻れることなく、上記共重合体との架橋構造を剛直に構成できると考えられるため、特に顕著な効果が得られると推測できる。
Ｒ₁はメチル基が好ましい。Ｒ₁´はエチル基が好ましい。Ｒ₂はメチレン基が好ましい。 In a preferred embodiment, a bismaleimide having one or more aromatic rings can be used as the polar monomer, and more preferably a substituent having one or more carbon atoms (an aliphatic substituent such as an alkyl group or a cyclic group such as a cycloalkyl group) can be used. Bismaleimide having one or more aliphatic substituents) on its aromatic ring can be used. In a more preferred embodiment, bismaleimide having the following structural formula can be used.

In the formula, R ₁ and R ₁ ′ are independent (each may be the same or different), a hydrogen atom or a substituent having 1 or more carbon atoms (preferably 1 to 20 carbon atoms). Such substituents include straight-chain or split-chain alkyl groups (methyl group, ethyl group, n-butyl group, tert-butyl group, hexyl group, etc.), (meth) acryloyl group, acyl group, substituted or unsubstituted aryl. The group and the like can be exemplified. Further, R ₂ in the formula is a bond (that is, two aromatic rings are directly bonded) or a divalent linker group having 1 or more carbon atoms (preferably 1 to 20 carbon atoms) (for example, a linear or linear group). It is an alkylene group of a split chain, an ether group, etc.). It is considered that the presence of a plurality of R ₁ and R _1'other than hydrogen atoms on the aromatic ring preferably improves the rigidity of the obtained crosslinked structure and contributes to the effect of the present invention. Although not bound by any particular theory, bismaleimides with such aromatic rings are not only highly insulating, but also without the easy twisting of their molecular structure due to the presence of bulky substituents. Since it is considered that the crosslinked structure with the above-mentioned copolymer can be rigidly formed, it can be presumed that a particularly remarkable effect can be obtained.
R ₁ is preferably a methyl group. R ₁ ′ is preferably an ethyl group. R ₂ is preferably a methylene group.

In another preferred embodiment, a polyfunctional (meth) acrylate derivative having a long-chain aliphatic substituent (for example, an alkyl group having about 5 to 20 carbon atoms) can be used as the polar monomer. The polyfunctional (meth) acrylate refers to a compound having two or more (meth) acryloyl groups. Since such a long-chain aliphatic substituent is bulky, it is considered that the crosslinked structure of the polar monomer and the above-mentioned copolymer can be maintained rigidly.

The amount of polar monomer that may be contained in the present composition can be arbitrarily set according to the intended use. In a preferred embodiment, the amount of the polar monomer is 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and further, with respect to 100 parts by mass of the total of the copolymer and the polar monomer. It may be preferably in the range of 0.1 to 15 parts by mass. By setting the amount of the polar monomer in this range, it becomes easy to appropriately control the dielectric constant and the dielectric loss tangent of the obtained cured product.

The molecular weight of the polar monomer is preferably less than 10,000, more preferably less than 6000.

<Additional resin (resin other than the above copolymer that may be contained in this composition)>
A resin compound other than the above-mentioned copolymer (hereinafter, also simply referred to as “additional resin”) may be further contained in the resin component in the present composition. As the additive resin, any one can be used as long as the effect brought about by the present composition is not impaired, and preferably one or more selected from the hydrocarbon-based elastomers, polyphenylene ethers, and aromatic polyene-based resins described later can be used. Among these, polyphenylene ether or hydrocarbon-based elastomer is more preferable. Among the hydrocarbon-based elastomers, conjugated diene-based polymers are preferable. Among the conjugated diene-based polymers, 1,2-polybutadiene is preferable. By using one or more selected from hydrocarbon-based elastomers, polyphenylene ethers, and aromatic polyene-based resins, there is an effect that the effect of the polar monomer can be promoted. The amount of the added resin may be preferably in the range of 1 to 500 parts by mass in total, and more preferably 1 to 300 parts by mass in total with respect to 100 parts by mass of the copolymer.

<Hydrocarbon elastomer>
The amount of the hydrocarbon-based elastomer is preferably 1 to 500 parts by mass, more preferably 1 to 200 parts by mass with respect to 100 parts by mass of the copolymer. The hydrocarbon-based elastomer that can be suitably used for the composition of the present invention may have a number average molecular weight of 20,000 or more, preferably 30,000 or more. Examples of hydrocarbon-based elastomers include ethylene-based and propylene-based elastomers, conjugated diene-based polymers and aromatic vinyl compounds-conjugated diene-based block copolymers or random copolymers, and hydrides thereof (hydrogenated. The one or more elastomers selected from the thing) can be mentioned. Examples of the ethylene-based elastomer include ethylene-α-olefin copolymers such as ethylene-octene copolymer and ethylene-1-hexene copolymer, EPR, and EPDM. Examples of the propylene-based elastomer include propylene-α-olefin copolymers such as atactic polypropylene, polypropylene with low stereoregularity, and propylene-1-butene copolymer.

<Conjugated diene polymer>
Examples of the conjugated diene polymer include polybutadiene and 1,2-polybutadiene. Examples of the aromatic vinyl compound-conjugated diene-based block copolymer or random copolymer, and hydrogenated products thereof (hydrogenates) include SBS, SIS, SEBS, SEPS, SEEPS, and SEEBS. The 1,2-polybutadiene that can be suitably used can be obtained, for example, as a product of JSR Corporation, or obtained from Nippon Soda Corporation under the product names of liquid polybutadiene: product names B-1000, B-2000, and B-3000. can. Further, as a copolymer containing a 1,2-polybutadiene structure that can be preferably used, "Ricon 100" manufactured by TOTAL CRAY VALLEY can be exemplified. When one or more resins selected from these hydrocarbon-based elastomers are liquid (generally 300,000 mPa · s or less) at room temperature (25 ° C.), the composition of the present invention is easy to handle and moldable in an uncured state. From the viewpoint of (handleability as a thermoplastic resin), the amount used is preferably in the range of 1 to 30 parts by mass, particularly preferably 1 to 20 parts by mass with respect to 100 parts by mass of the copolymer.

<Polyphenylene ether>
As the polyphenylene ether, a commercially available known polyphenylene ether can be used. The number average molecular weight of the polyphenylene ether is arbitrary, and the number average molecular weight is preferably 10,000 or less, most preferably 5,000 or less in consideration of the molding processability of the composition. The number average molecular weight may be preferably 500 or more. Further, in the case of addition for the purpose of curing the composition of the present invention, it is preferable that the molecular end is modified, and / or it is preferable that the composition has a plurality of functional groups in one molecule. Examples of the functional group include an allyl group, a vinyl group, an epoxy group and the like. As the functional group, a radically polymerizable functional group is preferable. As the radically polymerizable functional group, a vinyl group is preferable. As the vinyl group, a (meth) acrylic group or an aromatic vinyl group is preferable. That is, in the composition of the present invention, a bifunctional polyphenylene ether in which both ends of the molecular chain are modified with a radically polymerizable functional group is particularly preferable. Examples of such polyphenylene ethers include SABIC's Noryl (trademark) SA9000 and the like, and particularly preferably, a bifunctional polyphenylene ether oligomer (OPE-2St) manufactured by Mitsubishi Gas Chemical Company, Inc. can be used. The amount of the polyphenylene ether used in the composition of the present invention is preferably 1 to 500 parts by mass, more preferably 1 to 300 parts by mass, still more preferably 1 to 200 parts by mass with respect to 100 parts by mass of the copolymer.

<Aromatic polyene resin>
The aromatic polyene-based resin includes a divinylbenzene-based reactive multi-branched copolymer (PDV) manufactured by Nittetsu Chemical & Materials Co., Ltd. For such PDV, for example, the document "Synthesis of polyfunctional aromatic vinyl copolymer and development of new IPN type low dielectric loss material using it" (Honest Kawabe et al., Journal of Electronics Packaging Society p125, Vol. 12 No. 2 (2009)). Further, examples of the aromatic polyene-based resin include the aromatic polyene polymer resin having the above-mentioned aromatic polyene monomer as a main constituent unit.

<Curing agent>
As the curing agent that may be contained in the present composition, a known curing agent that can be conventionally used for polymerization or curing of aromatic polyenes and aromatic vinyl compounds may be used. Examples of such a curing agent include a radical polymerization initiator, a cationic polymerization initiator, and an anionic polymerization initiator, but a radical polymerization initiator may be preferably used. Preferred are organic peroxide-based (peroxide), azo-based polymerization initiators, and the like, which can be freely selected depending on the intended use and conditions. Catalogs containing organic peroxides can be found on the NOF website, for example.
https://www.nof.co.jp/business/chemical/product01a.html
https://www.nof.co.jp/business/chemical/product01b.html
https://www.nof.co.jp/business/chemical/product01c.html
It can be downloaded from. Organic peroxides are also listed in the catalogs of Fujifilm Wako Pure Chemical Industries, Ltd. and Tokyo Chemical Industry Co., Ltd. The curing agent used in the present invention is available from these companies. Further, a known photopolymerization initiator using light, ultraviolet rays, or radiation can also be used as a curing agent. Examples of the curing agent using the photopolymerization initiator include a photoradical polymerization initiator, a photocationic polymerization initiator, and a photoanionic polymerization initiator. Such a photopolymerization initiator can be obtained from, for example, Tokyo Chemical Industry Co., Ltd. Furthermore, it can be cured by radiation or the electron beam itself. Further, it is also possible to carry out cross-linking and curing by thermal polymerization of the contained raw materials without containing a curing agent.

The amount of the curing agent used is not particularly limited, but generally 0.01 to 10 parts by mass is preferable with respect to 100 parts by mass of the composition (preferably excluding the curing agent and the solvent). When a curing agent such as a peroxide-based or azo-based polymerization initiator is used, the curing treatment is performed at an appropriate temperature and time in consideration of its half-life. The conditions in this case are arbitrary according to the curing agent, but generally, a temperature range of about 50 ° C. to 180 ° C. is suitable.

<Other monomers>
The present composition may further contain a monomer other than the polar monomer described above (hereinafter, also referred to as "second monomer" or "second monomer"). The amount of such a second monomer is arbitrary, but is preferably 300 parts by mass or less with respect to 100 parts by mass of the copolymer. The present composition may be substantially free of the second monomer. When the second monomer is contained, 1 part by mass or more is preferable, and 5 parts by mass or more is more preferable. When the amount of the second monomer is 300 parts by mass or less, the uncured composition does not have a viscous property, and the molding process as a thermoplastic resin becomes easy. Further, when the content of the second monomer, which is easily volatilized, is below a certain level, the odor at the uncured stage does not become a problem. When a solvent is added to the composition to form a varnish-like product, there is a problem that the monomer is lost as the solvent evaporates during use, and the substantial content of the second monomer tends to decrease. Further, when the product form is an uncured sheet, if a certain amount or less of the second monomer is contained, the content of the second monomer is unlikely to change during storage. The second monomer preferably used in the composition of the present invention preferably has a molecular weight of less than 1000, more preferably less than 500. The monomers that can be suitably used in the composition of the present invention are aromatic vinyl compound monomers, aromatic polyene monomers, and / or polar monomers. As the monomer, a monomer that can be polymerized by a radical polymerization initiator is preferable, and one or more of the group consisting of an aromatic vinyl compound and an aromatic polyene is more preferable. Further, BVPE (1,2-bis (vinylphenyl) ethane) described in JP-A-2003-212941 can also be preferably used.

From the viewpoint of increasing the mechanical strength (elastic modulus) of the cured product at high temperature, the aromatic vinyl compound is preferably 50 parts by mass or more and 250 parts by mass or less, and 80 parts by mass or more and 200 parts by mass with respect to 100 parts by mass of the copolymer. The following are more preferable. From the viewpoint of increasing the mechanical strength (elastic modulus) of the cured product at high temperature, the amount of aromatic polyene is preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the copolymer. When an aromatic vinyl compound and an aromatic polyene are used, the mass ratio of the aromatic vinyl compound to the aromatic polyene is such that the aromatic vinyl compound and the aromatic polyene have a total of 100 parts by mass, and the aromatic vinyl compound: aromatic polyene = 70. It is preferably from 99: 1 to 30, and more preferably from 85 to 95: 5 to 15.

<Solvent>
An appropriate solvent may be added to the composition of the present invention, if necessary. The solvent is used to adjust the viscosity and fluidity of the composition. The solvent is preferably volatile, and for example, cyclohexane, toluene, ethylbenzene, acetone, isopropanol and the like are used. The amount used is preferably 10 parts by mass or less with respect to 100 parts by mass of the above-mentioned copolymer from the viewpoint of molding processability and handling of the composition before curing as a thermoplastic resin, and the thermoplasticity of the composition before curing is preferable. From the viewpoint of molding processability and handling as a resin, and from the viewpoint of removal during and after curing, it is more preferable that no solvent is substantially used. Not substantially used is preferably 5 parts by mass or less, more preferably 1 part by mass or less, and most preferably 0 parts by mass. When used as a varnish, it is preferable to add an appropriate solvent to the composition of the present invention. The solvent is used to adjust the viscosity and fluidity of the composition as a varnish. As the solvent, a solvent having a boiling point of a certain level or higher is preferable because the thickness of the applied film becomes uniform when the boiling point under atmospheric pressure is high, that is, when the volatility is low. The preferred boiling point is 100 ° C. or higher, more preferably 130 ° C. or higher and 300 ° C. or lower under atmospheric pressure. Suitable solvents for such varnishes include cyclohexane, toluene, xylene, mesitylene, tetralin, acetone, ethylbenzene, limonene, mixed alkane, mixed aromatic solvents, ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol. Monobutyl ether or the like is used. The amount used is preferably in the range of 10 to 2000 parts by mass, more preferably 5 to 500 parts by mass, still more preferably 10 to 300 parts by mass with respect to 100 parts by mass of the composition of the present invention.

In the present specification, the method for determining the number average molecular weight of the above-mentioned copolymer and other polymers is as follows. The molecular weight is determined as a number average molecular weight (Mn) in terms of standard polystyrene using GPC (gel permeation chromatography). The measurement can be performed under the following conditions.

(When the number average molecular weight is 1000 or more)
Column: TSKgel Multipole Hxl-M φ7.8 × 300 mm (manufactured by Tosoh Corporation) is used by connecting two in series.
Column temperature: 40 ° C
Solvent: THF
Liquid flow rate: 1.0 ml / min.
Detector: RI detector (differential refractive index detector)

(When the number average molecular weight is less than 1000)
Column: One TSKgelG3000HXL φ7.8 × 300mm (manufactured by Tosoh), one TSKgelG2000HXL φ7.8 × 300mm (manufactured by Tosoh), and four TSKgelG1000HXL φ7.8 × 300mm (manufactured by Tosoh) are connected in series.
Column temperature: 40 ° C
Solvent: THF
Liquid flow rate: 0.5 ml / min.
Detector: RI detector (differential refractive index detector)

<Filling agent>
Further, an arbitrary amount of a filler may be added to the composition depending on the intended use. Such a filler may be an inorganic filler, and can be added for the purpose of controlling the coefficient of thermal expansion, controlling the thermal conductivity, and reducing the price. The amount of the filler used may be increased to 2000 parts by mass with respect to 100 parts by mass of the total of the copolymer and the polar monomer, for example. In particular, when adding an inorganic filler, it is preferable to use a known surface modifier, for example, a silane coupling agent. In particular, when a composition excellent in low dielectric constant and low dielectric loss, which is one of the objects of the present invention, is aimed at, boron nitride (BN) or silica, particularly molten silica, is preferable as the inorganic filler. .. From the viewpoint of low dielectric properties, the dielectric constant becomes particularly high when a large amount is added and blended. Therefore, it is preferably less than 500 parts by mass, more preferably less than 100 parts by mass of the total of the copolymer and the polar monomer. Use less than 400 parts by mass of filler. Further, in order to improve and improve the low dielectric property (low dielectric constant, low dielectric loss tangent), a hollow filler or a filler having a shape with many voids may be added.

When silica is used as the filler, spherical silica powder can be preferably used, and more preferably surface-treated silica can be used. Hereinafter, silica may be referred to as spherical silica powder. The volume ratio of the total of the copolymer and the polar monomer to the spherical silica powder is in the range of 95 to 50: 5 to 50, more preferably in the range of 90 to 70: 10 to 30, still more preferably. It may be in the range of 85 to 75:15 to 25.

The surface-treated silica refers to silica whose dielectric loss tangent is reduced by surface-treating the raw material silica. Examples of such surface treatment include heat treatment and treatment with various coupling agents including a silane coupling agent. Preferably, as such a surface treatment, the methods described in International Publication No. 2020/195205 by the Applicant and pending Japanese Patent Application No. 2020-077291 can be used. In a preferred embodiment, spherical silica powder may be used as silica, and the surface treatment received by the spherical silica powder is such that the raw material spherical silica powder is heated at a temperature of 500 to 1100 ° C, preferably 500 to 1000 ° C. The heat treatment may be carried out for a predetermined time in which (° C.) × heating time (h) is 1000 to 26400 (° C. h), preferably 1800 to 17600 (° C. h). The treatment is preferably carried out by flowing the raw material silica powder in an inert atmosphere (nitrogen, argon, etc.) while flowing the powder. It is preferable to select the temperature and time of the treatment so that the obtained silica satisfies at least one of the following conditions (a) to (b).
(A) The number of water molecules desorbed at 500 ° C. to 1000 ° C. when the temperature is raised to 1000 ° C. under the condition of 25 to 30 ° C./min is 0.01 mmol / g or less.
(B) The specific surface area is 1 to 30 m ² / g, preferably 3 to 10 m ² / g.
When the above conditions are satisfied, mixing with the resin component becomes easy, and the effect of reducing the dielectric loss tangent can be obtained.

When spherical silica powder is used as silica, the average particle size (d50) of the spherical silica powder is preferably 0.01 to 100 μm, more preferably 0.1 to 10 μm, and most preferably 0.3 to 1 μm. d50 is a value with a cumulative volume of 50%.

The silica immediately after the surface treatment may be naturally allowed to cool in a furnace, cooled to 200 ° C. or lower, dried in a vacuum dryer, and then recovered in a moisture-proof aluminum bag.

Any method can be used for producing silica as a raw material, and examples thereof include a powder melting method in which spherical silica powder is obtained by passing it through a high temperature range having a temperature higher than the melting point and spheroidizing it. In the silica before surface treatment, the peak intensity of the silica wave number 3735 cm ^-1 to 3755 cm ^-1 measured by the diffuse reflection FT-IR method was defined as A, and the peak intensity of the wave number 3660 cm ^-1 to 3680 cm ^-1 was defined as B. When, it is preferable that the B / A is 3.0 or less.

The density of silica is preferably 1.8 to 2.4 g / cm ³ . Within this range, it is possible to obtain an effect that the amount of voids in the silica particles is appropriate, the silica crystal structure is appropriate, and the coefficient of thermal expansion is appropriately suppressed.

When spherical silica powder is used as silica, the average circularity of the spherical silica powder is preferably 0.85 or more, more preferably 0.90 or more. When the average circularity is 0.85 or more, the viscosity does not increase too much when mixed with the resin component, and the fluidity does not easily decrease, so that the processability and the filling property are improved. Further, as silica, spherical silica powder and other silica (preferably fused silica) can be used in combination.

<Other fillers>
Further, if necessary, a known inorganic or organic filler other than the above-mentioned surface-treated silica may be further added. These fillers are added for the purpose of controlling the coefficient of thermal expansion, controlling the thermal conductivity, and reducing the price, and the amount used thereof is arbitrary depending on the purpose. The composition of the present invention can contain a large amount of an inorganic filler in particular, and the amount thereof can be added at the maximum, and can reach 2000 parts by mass with respect to 100 parts by mass of the copolymer. In particular, when adding an inorganic filler, it is preferable to use a known surface modifier, for example, a silane coupling agent. In particular, when a composition excellent in low dielectric constant and low dielectric loss, which is one of the objects of the present invention, is aimed at, boron nitride (BN) is preferable as the inorganic filler. From the viewpoint of low dielectric property, since the dielectric constant becomes particularly high when added in a large amount, a filler of less than 500 parts by mass, more preferably less than 400 parts by mass, is preferably used with respect to 100 parts by mass of the copolymer. Use. Further, in order to improve and improve the low dielectric property (low dielectric constant, low dielectric loss tangent), a hollow filler or a filler having a shape with many voids may be added.

It is also possible to use an organic filler such as high molecular weight polyethylene or ultra high molecular weight polyethylene instead of the inorganic filler. It is preferable that the organic filler is crosslinked by itself from the viewpoint of heat resistance, and it is preferable that the organic filler is blended in the form of fine particles or powder. These organic fillers can also suppress the increase in dielectric constant and dielectric loss tangent.

On the other hand, the composition of the present invention is mixed with a high dielectric constant insulator filler having a dielectric constant of preferably 3 to 10000, more preferably 5 to 10000 at 1 GHz and dispersed to increase the dielectric loss tangent (dielectric loss). It is possible to produce an insulating cured product having a high dielectric constant insulating layer having a dielectric constant of 20 or less while suppressing the above. By increasing the dielectric constant of the film made of an insulating cured product, it is possible to reduce the size of the circuit and the capacity of the capacitor, which can contribute to the miniaturization of high-frequency electric components. The high dielectric constant layer and the low dielectric loss tangent insulating layer are suitable for applications such as capacitors, inductors for resonant circuits, filters, and antennas. Examples of the high dielectric constant insulator filler used in the present invention include an inorganic filler and metal particles subjected to an insulating treatment. Specific examples are known high dielectric constant inorganic fillers such as barium titanate and strontium titanate, and other examples are specifically described in, for example, Japanese Patent Application Laid-Open No. 2004-087639.

<Other additives>
The composition may further comprise one or more selected from flame retardants, surface modifiers. The composition of the present invention may be a matrix of cured products and may contain one or more selected from these fillers, flame retardants and surface modifiers in order to be excellent in filling properties of other materials when cured. Even after being cured, the cured product tends to exhibit impact resistance and toughness.

<Flame retardant>
A known flame retardant can be used in the composition of the present invention. Preferred flame retardants are known organic phosphorus-based flame retardants such as phosphoric acid esters or condensates thereof, known brominated-based flame retardants, and red phosphorus from the viewpoint of maintaining low dielectric constant and low dielectric loss tangent. In particular, among the phosphoric acid esters, a compound having a plurality of xylenyl groups in the molecule is preferable from the viewpoint of flame retardancy and low dielectric loss tangent property.

In addition to flame retardants, antimony compounds such as antimony trioxide, antimony tetroxide, antimony pentoxide, and sodium antimonate, or melamine, triallyl-1,3,5-triazine-2,3,4-, are used as flame retardant aids. A nitrogen-containing compound such as (1H, 3H, 5H) -trione, 2,4,6-trialilyloxy 1,3,5-triazine may be added. The total amount of these flame retardants and flame retardant aids is usually preferably 1 to 100 parts by mass with respect to 100 parts by mass of the composition. Further, 30 to 200 parts by mass of the polyphenylene ether (PPE) -based resin having a low dielectric constant and excellent flame retardancy may be used with respect to 100 parts by mass of the flame retardant.

<Surface modifier>
The composition of the present invention may contain various surface modifiers for the purpose of improving adhesion to fillers, copper plates, and wiring. The amount of the surface modifier used is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the composition of the present invention other than the surface modifier. Examples of the surface modifier include various silane coupling agents, titanate-based coupling agents and the like. As various silane coupling agents and titanate-based coupling agents, one or more may be used.

In the present invention, the compounding ratio of the copolymer, the monomer, the additive resin, and the solvent of the composition may be changed within the above range, or further, the flame retardant, the filler, and the surface modifier may be used. By changing the compounding ratio, the fluidization temperature of the present curable resin or the composition can be adjusted according to the purpose and the molding method. Specifically, the composition of the present invention can take the product form of "thermoplastic composition", "semi-cured state (B stage sheet or the like)", and "varnish".

The composition of the present invention is obtained by mixing, dissolving or melting the copolymer and one or more other components as described above, and any known method can be adopted as the method of mixing, dissolving and melting. ..

<Thermoplastic composition, molded product>
The composition of the present invention can also show the properties of a thermoplastic resin when a copolymer having a molecular weight in a certain range or more is used and the predetermined additive resin is contained. Therefore, under conditions that do not cause cross-linking, it is possible to form a sheet, a tube, a strip, a pellet, or the like in a substantially uncured state by a known molding method as a thermoplastic resin. The molded product may then be crosslinked (cured).

Moreover, the preferable embodiment of this composition is as follows. A constant one or more resins selected from the above hydrocarbon-based elastomers, polyphenylene ethers, olefins-aromatic vinyl compounds-aromatic polyene copolymerized oligomers, or aromatic polyene-based resins, excluding resins that are liquid at room temperature. When it is contained in a proportion or more, the molding process as a thermoplastic resin becomes easy in the uncured state as well. Specifically, preferably, the hydrocarbon-based elastomer (excluding the liquid resin) and / or the polyphenylene ether can be added in the range of 30 to 200 parts by mass with respect to 100 parts by mass of the copolymer. When the added resin is liquid at room temperature, it can be added in the range of preferably 1 to 30 parts by mass, particularly preferably 1 to 20 parts by mass with respect to 100 parts by mass of the copolymer. The amount of the polar monomer used in the present thermoplastic composition is preferably 15 parts by mass or less with respect to 100 parts by mass of the total of the copolymer and the polar monomer. The number average molecular weight of the copolymer used is 500 or more and 100,000 or less, preferably 20,000 or more and 100,000 or less, and more preferably 30,000 or more and 100,000 or less. The above thermoplastic composition utilizes the thermoplasticity below the working temperature of the curing agent, is molded into various shapes such as a sheet in advance, and if necessary, is combined with a semiconductor element, wiring, or a substrate and a laminate. It may be heat-cured and adhered.

The composition of the present invention may be provided as a sheet obtained by molding a composition heated and melted at a temperature equal to or lower than the working temperature of the curing agent or the decomposition temperature by a known method. Molding into a sheet may be extrusion molding with a T-die, double rolls, or extrusion laminating into a base film. In this case, the composition, copolymer / monomer mass ratio, solvent, additive resin, flame retardant, etc. Make selections and adjustments. The sheet in this case is substantially uncured. After that, it undergoes various processing and assembling steps, and finally is treated at a temperature and time equal to or higher than the working temperature of the curing agent or the decomposition temperature to be completely cured. Such a technique is a general technique used for an ethylene-vinyl acetate resin-based cross-linking sealant sheet of a solar cell (photovoltaic power generation device).

<Molded body in semi-cured state (B stage sheet, etc.)>
Further, the composition of the present invention is a molded product, for example, a sheet, a tube, etc. in a partially crosslinked state, for example, a state in which a part of the curing agent contained therein is reacted and semi-cured (so-called B stage state). It is also possible to. For example, by adopting a plurality of curing agents and / or curing conditions having different curing temperatures, semi-curing can be performed, and the melt viscosity and fluidity can be controlled to bring the B stage state. That is, by the first stage curing (partial curing), the present curable resin or composition is formed into an easy-to-handle B stage sheet, which is laminated on an electronic device or a substrate and crimped, and then the second stage curing (partial curing). It is also possible to perform complete curing) to obtain the final shape. In this case, the composition of the composition, that is, the mass ratio of the copolymer / monomer is selected, a solvent, an additive resin, and a flame retardant are added if necessary, and the composition further contains a curing agent such as a peroxide. Can be partially cured, adjusted to a sheet shape (B stage state), the device can be molded and assembled, and then heated under pressure to be completely cured. As a method for partially curing the composition, a known method can be adopted. For example, peroxides having different decomposition temperatures are used in combination and treated for a predetermined time at a temperature at which only one of them substantially acts to obtain a semi-cured product sheet, and finally a temperature at which all the curing agents act is sufficient. There is a method of treating with time and completely curing.

Further, the molded product may be a sheet. The sheet may be uncured (semi-cured) to the extent that the sheet shape can be maintained, or may be completely cured. The degree of curing of the composition can be quantitatively measured by a known dynamic mechanical analysis (DMA, Dynamic Mechanical Analysis).

<Varnish-like composition and its molded product>
The composition of the present invention may be in the form of a viscous liquid varnish depending on its composition and compounding ratio. For example, it can be made into a varnish by using a sufficient amount of solvent and / or by using an appropriate amount of a liquid monomer. In particular, when used as a varnish, it is preferable to add an appropriate solvent to the composition of the present invention. The solvent is used to adjust the viscosity and fluidity of the composition as a varnish. As the solvent, a solvent having a boiling point of a certain level or higher is preferable because the thickness of the applied film becomes uniform when the boiling point under atmospheric pressure is high, that is, when the volatility is low. The preferred boiling point is approximately 100 or more, preferably 110 ° C. or higher and 300 ° C. or lower under atmospheric pressure. As a solvent suitable for such a varnish, toluene, xylene, mesitylene, ethylbenzene, limonene, ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether and the like are used. The amount used is preferably in the range of 10 to 2000 parts by mass with respect to 100 parts by mass of the composition of the present invention. The varnish-like composition of the present invention can also be prepared by utilizing a polymerization solution containing the copolymer of the present invention obtained by polymerization. For example, the polymerization solution may be concentrated or treated to remove residual monomers, and if necessary, a solvent, other resin components, various additives, etc. may be added to adjust the component concentration and solution viscosity. You can also.

The varnish can be, for example, applied or impregnated on a substrate, and the solvent or the like can be removed by drying or the like to form an uncured or semi-cured molded product. Generally, the present molded product has a sheet, film, or tape-like form. The obtained uncured or semi-cured molded product is cured.

<Curing>
The composition can be cured by a known method with reference to the curing conditions (temperature, time, pressure) of the contained curing agent. When the curing agent used is a peroxide, the curing conditions can be determined with reference to the half-life temperature and the like disclosed for each peroxide.

<Cured product of composition>
The dielectric constant and the dielectric loss tangent of the cured product obtained from the composition of the present invention are measured by a known resonator method (cavity resonator perturbation method, balanced disc resonator method, etc.). In the present specification, the resonator method shall be performed in the measurement frequency range of 27 GHz to 42 GHz. The dielectric constant of the cured product is preferably 2.7 or less and 2.0 or more, and particularly preferably 2.5 or less and 2.0 or more. The dielectric loss tangent of the cured product is 1.5 × 10 ^-3 or less, preferably 0.3 × 10 ^-3 or more and 1.5 × 10 ^-3 or less. The volume resistivity of the cured product is preferably 1 × 10 ¹⁵ Ω · cm or more. These values are preferable values, for example, as an electric insulating material for high frequencies of 3 GHz or higher. Since the copolymer used in the composition of the present invention is relatively soft and has abundant tensile elongation, the cured product obtained from the composition using the copolymer has relatively high impact resistance while exhibiting sufficient mechanical characteristics. It can have a feature that can follow the thermal expansion of the base material. That is, the cured product of the present invention has a tensile elastic modulus preferably less than 30 GPa and 0.5 GPa or more measured at room temperature (23 ° C.). Further, particularly when a relatively large amount of filler is blended, the present tensile elastic modulus may take a value of 3 GPa or more and 20 GPa or less. The tensile breaking point strength is preferably less than 200 MPa, 3 MPa or more, and the tensile breaking point elongation is preferably 0.1% or more and less than 300%, and more preferably 1% or more and less than 50%. Further, especially when a relatively large amount of filler is blended, the elongation at the breaking point of this tensile break may take a value of less than 30%. Those skilled in the art can determine the composition of a composition having the above-mentioned physical characteristic parameters and prepare a cured product by referring to the information described in the present specification and publicly known materials. The cured product obtained from the composition of the present invention can be practically used even under conditions in which the amount of polar monomers in the composition and the amount of aromatic polyenes as components of other monomers are suppressed to a certain ratio or less. It is possible to show sufficient heat resistance and mechanical properties under high temperature. It is important to keep the aromatic polyene as a monomer or a component of the monomer below a certain ratio in order to maintain the moldability as a thermoplastic resin even in the uncured state as described above. be.

The storage elastic modulus of the cured product at 250 ° C. may be 10 MPa or more and 10 GPa or less, preferably 15 MPa or more and 1 GPa or less. Having such a storage elastic modulus has an effect that the cured product has a hardness suitable for a substrate / substrate application.

In a preferred embodiment, the cured product of the composition has a small ratio of storage elastic modulus at 25 ° C. divided by storage elastic modulus at 250 ° C. (ie, does not excessively lose viscoelasticity even at high temperatures). This property indicates that the crosslink density of the present composition does not easily decrease even at high temperatures. The value of the ratio is preferably 20 or less, preferably 2 or more, more preferably 10 or less, and further preferably 2 or more and 10 or less. The storage elastic modulus of the cured product of the present composition can be measured using a known dynamic viscoelasticity measuring device.

<General use of composition>
The composition of the present invention is a substrate / substrate such as a single-layer or multi-layer printed circuit board, a flexible printed circuit board, a so-called single-layer or multi-layer CCL (copper clad laminate), or a single-layer or multi-layer FCCL (flexible copper clad laminate) substrate. Can be used as. Further, it can be used as various insulating materials for wiring, preferably wiring of high frequency signals, such as coverlays, solder resists, build-up materials, interlayer insulating agents, bonding sheets, interlayer adhesives, and bump sheets for flip chip bonders. can.

<Use of the composition as an uncured sheet or a partially cured sheet>
The uncured sheet or partially cured sheet of the composition of the present invention can be suitably used as an electrically insulating material for high frequency. For example, it can be suitably used as a build-up film, a bonding sheet, a coverlay sheet, a bump sheet for a flip chip bonder, or an insulating layer or an adhesive layer for a substrate. The composition of the present invention is used as a substitute for the conventionally used epoxy resin or silicone resin sheets. The composition of the present invention can form a cured insulating layer or a cured matrix phase having a low dielectric constant and a low dielectric loss by performing a curing treatment. The thickness of the sheet is generally 1 to 300 μm. This sheet may contain a woven fabric such as glass cloth or ceramic fiber or a non-woven fabric. This sheet may be impregnated or may be multilayered with these. Further, as an antenna cable for a mobile phone or the like, a flexible bendable wiring that is partially or wholly insulated by this sheet can be used instead of the conventional coaxial cable. For example, using LCP (liquid crystal polymer), PPE sheet, fluororesin, or polyimide resin as a base material, the wiring is coated with the sheet or B stage sheet (coverlay sheet) of the present invention, cured, and adhered to the base material. It can be used as an insulating material.

A multilayer wiring board in which the cured product obtained by using the composition of the present invention is an insulating layer can be a wiring board having low dielectric loss and excellent high frequency characteristics. In this case, in addition to low dielectric loss, heat resistance that can withstand solder, and some degree of softness, elongation, and impact resistance that can withstand stress due to heat cycle or thermal expansion difference are merits. For example, a cloth made of glass or quartz, a non-woven fabric, a film material, a ceramic substrate, a glass substrate, a core material such as a general-purpose resin plate such as an epoxy, a core material such as a general-purpose laminated plate, and a conductor foil with an insulating layer made of this cured product are laminated and pressed. This makes it possible to manufacture a wiring board. Further, a slurry or a solution containing the present composition may be applied to a core material (for example, an inner layer), dried and cured to form an insulating layer. The thickness of the insulating layer is generally 1 to 300 μm. Such a multi-layer wiring board can be used in multiple layers or integrated.

The cured product obtained by curing the varnish-like composition of the present invention can be suitably used as an electrical insulating material as described above, and in particular, a potting material, a surface coating agent, a coverlay, a solder resist, a build-up material, etc. As an underfill material, filling insulation, interlayer insulating agent, interlayer adhesive, or as a cured product, as a printed circuit board, flexible printed circuit board, CCL (copper clad laminate, copper clad laminate) substrate, FCCL (flexible copper clad laminate) substrate Alternatively, it can be used as an electrically insulating material, particularly as an electrically insulating material for high frequencies, as a cured product of a build-up film, a bonding sheet, a coverlay sheet, and a bump sheet for a flip tip bonder.

From another point of view, the present invention contains an olefin-aromatic vinyl compound-aromatic polyene copolymer, has a storage elastic modulus of 10 MPa or more and 10 GPa or less at 250 ° C., and has a dielectric constant of 23 ° C., 10 GHz or 25 GHz to 40 GHz. It is possible to provide an electrically insulating material having a dielectric constant of 2.5 or less and 2.0 or more and a dielectric loss tangent of 1.2 × 10 ^-3 or less.

The uncured or semi-cured thermoplastic composition of the present invention is a laminated body by adhering it to a metal foil, particularly a copper foil for wiring, by heat and pressure treatment without applying an adhesive or adhering treatment. You can also get. Here, metal leaf is a concept including metal wiring. In particular, in the olefin-aromatic vinyl compound-aromatic polyene copolymer, preferably when a copolymer having an aromatic vinyl compound content of 10% by mass or more is used, and / or whether the olefin is ethylene alone or not. Alternatively, the mass ratio of the olefin monomer component other than ethylene to the ethylene monomer component contained in the olefin is 1/7 or less, and the measurement according to the Japanese Industrial Standards (JIS) C6481: 1996 is 1 N / mm. The above peeling strength can be given. Further, it is more preferable to give a peel strength of 1.3 N / mm or more. More preferably, in the above-mentioned copolymer, the olefin is ethylene alone, or the olefin monomer component other than ethylene is 1/10 or less of the ethylene monomer component contained in the olefin, and most preferably the copolymer. If the content of the α-olefin monomer unit other than ethylene contained is 4% by mass or less, or if the olefin is ethylene alone, the peel strength can be further improved. In general, it is known that the dielectric property of a laminated body such as a copper-clad laminated sheet is deteriorated by performing an adhesive treatment, and even without such treatment, Japanese Industrial Standards (JIS) C6481: It is preferable to give a peel strength of 1 N / mm or more by the measurement according to 1996. As described above, the uncured or semi-cured thermoplastic composition of the present invention is a metal leaf such as a copper foil for wiring by a curing treatment such as a heat-pressurizing treatment without applying an adhesive or an adhesive treatment. It is possible to bond with. However, in the present invention, with respect to imparting adhesiveness to metal foils and other members, other adhesiveness-imparting measures (adhesive application, adhesive treatment, etc.) including the addition of the above-mentioned "surface modifier" are to be implemented. It does not prevent anything. Of course, it is also possible to cure the laminate to obtain a cured product.

The uncured or semi-cured composition of the present invention can also be cured with a LCP (liquid crystal polymer) layer under relatively mild curing conditions to provide high adhesive strength. Here, the LCP layer may be specifically an LCP sheet or a film. Therefore, for example, an LCP sheet, a metal leaf, preferably a copper foil, and various laminates containing the composition of the present invention can be obtained. The number of layers of this laminate and the order of lamination are arbitrary. As such an example of the present invention, the composition of the present invention is useful as an adhesive layer between a metal foil (copper foil) and an LCP sheet. The composition of the present invention can exhibit high adhesiveness to both a metal foil and an LCP sheet. Conventionally, in order to bond the LCP sheet and the copper foil, it is necessary to heat the LCP to a melting point (generally 280 ° C. to 330 ° C.) or a temperature close to the melting point and crimp it. However, by using the composition of the present invention as an adhesive layer, it is possible to bond the LCP and the metal leaf at a lower temperature by crimping substantially near the curing temperature of the composition of the present invention. At that time, the low dielectric constant and the low dielectric loss tangent value of the cured product of the composition of the present invention impart usefulness as wiring for particularly high-frequency signal transmission of the present laminated body. As another example of the present laminate, there is a structure in which the metal wiring arranged on the LCP layer, preferably the copper wiring, is covered with the cured body layer of the composition of the present invention from the side opposite to the LCP layer side. .. It is used as a so-called coverlay on LCP board wiring.

Here, the LCP (liquid crystal polymer) refers to a thermoplastic polymer having a liquid crystal state or a property of optically birefringent when melted. Examples of the LCP include a lyotropic liquid crystal polymer that exhibits liquid crystallinity in a solution state and a thermotropic liquid crystal polymer that exhibits liquid crystallinity when melted. The liquid crystal polymer is classified into type I, type II, and type III according to the heat distortion temperature, and any type may be used. Examples of the liquid crystal polymer include thermoplastic aromatic liquid crystal polyesters and thermoplastic aromatic liquid crystal polyester amides having an amide bond introduced therein. The LCP may be a polymer in which an imide bond, a carbonate bond, an isocyanate-derived bond such as a carbodiimide bond or an isocyanurate bond is further introduced into an aromatic polyester or an aromatic polyester amide. The melting point of the LCP is preferably 220 to 400 ° C., more preferably 260 to 380 ° C. by the DSC method. When the melting point is within the above range, a film or sheet having excellent extrusion moldability and heat resistance can be obtained. Such LCPs can be obtained from, for example, Ueno Fine Chemicals, Sumitomo Chemical, and Polyplastics. Here, the LCP sheet is a known LCP sheet, and its thickness is arbitrary. The LCP sheet can be obtained by a known method such as a T-die extrusion method, an inflation method, or an endless belt (double belt press) method.

The composition of the present invention, for example, a curable composition, has properties as a thermoplastic resin. Further, the cured product obtained by curing the curable composition has excellent low dielectric properties, has a high storage elastic modulus at high temperatures, and has a small coefficient of thermal expansion (thermal expansion coefficient, CTE). Especially suitable for various electronic board applications.

Hereinafter, the present invention will be described with reference to Examples, but the present invention is not construed as being limited to the following Examples.

The analysis of the copolymers obtained in the synthetic example and the comparative synthetic example was carried out by the following means.

The content of vinyl group units derived from ethylene, hexene, styrene, and divinylbenzene in the copolymer was determined by ¹ H-NMR from the peak area intensity assigned to each. The sample was dissolved in 1,1,2,2-tetrachloroethane by weight, and the measurement was performed at 80 to 130 ° C.

<Number average molecular weight>
For the molecular weight, the number average molecular weight (Mn) in terms of standard polystyrene was determined using GPC (gel permeation chromatography). The measurement was performed under the following conditions.
(When the number average molecular weight is 1000 or more)
Column: TSKgel Multipole Hxl-M φ7.8 × 300 mm (manufactured by Tosoh Corporation) was used by connecting two in series.
Column temperature: 40 ° C
Solvent: THF
Liquid flow rate: 1.0 ml / min.
Detector: RI detector (differential refractive index detector)

<Glass transition temperature (DSC measurement)>
The DSC measurement was performed using a DSC6200 manufactured by Seiko Electronics Co., Ltd. under a nitrogen stream. That is, using 10 mg of resin and 10 mg of α-alumina as a reference, using an aluminum pan, the temperature was raised from room temperature to 240 ° C at a heating rate of 10 ° C / min under a nitrogen atmosphere, and then cooled to −120 ° C at 20 ° C / min. did. After that, DSC measurement was performed while raising the temperature to 240 ° C. at a heating rate of 10 ° C./min to determine the glass transition temperature. The glass transition temperature referred to here is the supplementary glass transition start temperature of JIS K7121: 2012, and the gradient between the straight line extending the baseline on the low temperature side to the high temperature side and the curve of the stepwise change portion of the glass transition is maximized. It is the temperature of the intersection with the tangent line drawn at the point.

<Average particle size (d50)>
It was obtained from the volume particle size distribution curve obtained from a laser diffraction type particle size measuring instrument (Beckman Coulter "Model LS-230" type).

<Specific surface area>
The measurement cell was filled with 1 g of a sample, and the specific surface area was measured by a Maxorb HM model-1201 fully automatic specific surface area measuring device (BET one-point method) manufactured by Muntech. The degassing condition before the measurement was 200 ° C. for 10 minutes. The adsorbed gas was nitrogen.

<Permittivity and dielectric loss (dielectric loss tangent)>
For the dielectric constant and the dielectric loss tangent, a balanced disk resonator (manufactured by Keysight Technology Co., Ltd.) was used, and the dielectric characteristics were evaluated in the same manner. To evaluate the dielectric characteristics of a balanced disk resonator, prepare two samples (diameter 3 cm, thickness 0.2 to 0.6 mm) cut out from a sheet, sandwich a copper foil between them, and set them in the resonator. , The resonance frequency (f0) and the no-load Q value (Qu) of the peaks appearing at 27 to 42 GHz were measured. The permittivity from f0 and the dielectric loss tangent (tanδc) from Qu were calculated by the analysis software (Balanced type circular disk resonator (method) calculator, balanced disk resonator method analysis software) attached to the resonator. The measured temperature was 23 ° C. and the humidity was 50% RH.

<CTE (coefficient of linear expansion)>
CTE uses a thermomechanical analyzer (TMA: Thermal Analyzer, BRUKER AXS, now Netch Japan) with reference to the JPCA standard "Electronic Circuit Board Standard 3rd Edition", Section 16 Material Standards for Printed Wiring Boards. Used, width 3-5 mm, thickness 0.5-0.6 mm, chuck spacing 15-20 mm, tensile load 10 g, heating rate: measured under the conditions of 10 ° C / min, between 25 ° C and 150 ° C. The average value was calculated. In the composition according to the present invention, the CTE is required to be 130 ppm / K or less.

<Measurement of storage elastic modulus>
Using a dynamic viscoelasticity measuring device (TA Instruments, formerly Leometrics RSA-G2), the measurement was performed in a frequency range of 1 Hz and a temperature range of −60 ° C. to + 300 ° C. A measurement sample (3 mm × 40 mm) was cut out from a film having a thickness of about 0.1 to 0.3 mm and measured, and the storage elastic modulus was determined. The main measurement parameters related to the measurement are as follows.
Measurement frequency 1Hz
Temperature rise rate 3 ° C / min Sample measurement length 10 mm
Distortion 0.1%

<Olefin-aromatic vinyl compound-aromatic polyene copolymer>
With reference to the production methods of International Publication No. 00/37517, JP-A-2009-161743, and JP-A-2010-280771, the amount of monomer, ratio, polymerization pressure, and polymerization temperature were appropriately changed, and the P-1 was used together. A polymer was obtained. The total of the olefin monomer unit, the aromatic vinyl compound monomer unit, and the aromatic polyene monomer unit was set to 100% by mass. Table 1 shows the composition and number average molecular weight of the copolymer.

The main raw materials are as follows.
As divinylbenzene, divinylbenzene (meth, paramixture, divinylbenzene purity 81%) manufactured by Nittetsu Chemical & Materials Co., Ltd. was used. As the curing agent, NOF Corporation's Perhexin 25B (2,5-dimethyl-2,5-bis (t-butylperoxy) hexin-3) was used. As polar monomers, BMI-5100 (manufactured by Daiwa Kasei Kogyo Co., Ltd., 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide), TAIC (manufactured by Mitsubishi Chemical Corporation, triallyl isocyanate). Nurate) was used. In addition, OPE-2St (bifunctional polyphenylene ether oligomer manufactured by Mitsubishi Gas Chemical Company, Inc.) was used.

As silica, an SFP-130MC (d50 = 0.6 μm, specific surface area 6.2 m ² / g) dielectric loss tangent reduction treated product (“treated SFP-130MC”) manufactured by Denka Co., Ltd. was used. The SFP-130MC dielectric loss tangent reduction treated product is a surface-treated spherical silica powder produced by the method described in International Publication No. 2020/195205 and pending Japanese Patent Application No. 2020-077291. Specifically, the raw material spherical silica powder (SFP-130MC manufactured by Denka Co., Ltd.) is set to a temperature of 500 to 1000 ° C., and the heating temperature (° C.) × heating time (h) is set to 1800 to 17600 (° C. h). The one that had been heat-treated for hours was used. The treatment was carried out by flowing the raw material silica powder in an inert atmosphere.

Example 1
Using a container with a heating / cooling jacket and a stirring blade, 90 parts by mass of P-1 (ethylene-styrene-divinylbenzene copolymer) obtained in the synthesis example and BMI-5100 (Daiwa Kasei) as a polar monomer 10 parts by mass of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide (manufactured by Kogyo Co., Ltd.) was stirred and dissolved at about 40 ° C. Further, 1 part by mass of the curing agent Perhexin 25B (manufactured by NOF CORPORATION) was added to 100 parts by mass of the above mixture to dissolve the mixture, and the mixture was stirred and mixed to obtain a varnish-like composition.

The obtained composition was further stirred with Awatori Rentaro (manufactured by Shinky Co., Ltd.), and then placed on a preheated cellophane-lined glass plate with a silicone rubber mold (frame thickness 0.5 mm, or frame thickness 0.5 mm). It was poured into (1.0 mm), reduced pressure from atmospheric pressure to 10 hPa at 60 ° C. over 22 hours, and further dried for 3 hours to obtain a dry sheet. Further, it was sandwiched between glass plates and brought into close contact with a clip, and heat-treated at 120 ° C. for 30 minutes, 150 ° C. for 30 minutes, and then at 200 ° C. for 2 hours under a nitrogen atmosphere. After completion, the glass plate, the mold, and the like were removed to obtain a sheet-shaped cured product.

Example 2
A 20 vol% silica filler (SFP-130MC dielectric loss tangent reduction treated product) was added to 80 vol% (volume%) of the composition of Example 1 obtained as a sheet-shaped cured product, and the mixture was stirred to obtain a slurry-like varnish. Was performed in the same manner as in Example 1.

Example 3
The same procedure as in Example 1 was carried out except that 85 parts by mass of P-1 and 15 parts by mass of BMI-5100 were blended.

Comparative Examples 1 to 5
A sheet-shaped cured product according to each Comparative Example was obtained in the same manner as in Example 1 except that the component compositions shown in Table 2 were used.

In the cured products of the composition sheets obtained in Examples 1 to 3, both the dielectric constant and the dielectric loss tangent measured at the above-mentioned measurement frequency were very low, and the CTE was also lower than 130 ppm / K. Furthermore, in each of the examples, the value obtained by dividing the storage elastic modulus at 25 ° C. by the storage elastic modulus at 250 ° C. became low, confirming that the crosslink density was maintained even at high temperatures.

On the other hand, the cured products of the sheets obtained in Comparative Examples 1 to 4 had too high CTE and were not particularly suitable for CCL use. Further, although the CTE of Comparative Example 5 was low, the dielectric loss tangent was too high as in Comparative Example 3. Further, in Comparative Example 1, the viscosity was generally too low, the sample was stretched, and the storage elastic modulus could not be measured. In Comparative Examples 2 and 3, the viscosity was too low at 250 ° C., the sample was stretched, and the storage elastic modulus could not be measured.

From the above results, the cured product of this composition exhibits excellent low dielectric properties and low CTE characteristics, and is a practically sufficient cured product for CCL. Therefore, it was confirmed that the present invention can provide an electrically insulating material particularly for high frequency. This cured product can be suitably used as a thin film electrical insulating material and a high frequency electrical insulating material. This cured product is useful as a printed circuit board, a flexible printed circuit board, a single-layer or multi-layer CCL (copper clad laminate) substrate, and a single-layer or multi-layer FCCL (flexible copper clad laminate) substrate. Further, it can be suitably used as these interlayer adhesive layers and interlayer insulating layers.

Claims (16)

Olefin-aromatic vinyl compound-aromatic polyene copolymer and
A composition containing a polar monomer.
The value of the dielectric constant of the cured product of the composition obtained by the resonator method in the measurement frequency range of 27 GHz to 42 GHz is 2.7 or less.
The value of the dielectric loss tangent of the cured product of the composition obtained by the resonator method in the measurement frequency range of 27 GHz to 42 GHz is 1.5 × 10 ^-3 or less.
The CTE (coefficient of linear expansion) of the composition required based on the JPCA standard "Electronic Circuit Board Standard 3rd Edition", Section 16 "Material Standard for Printed Wiring Board" is characterized by being 130 ppm / K or less. The composition. The polar monomer is selected from the group consisting of maleimide, bismaleimide, maleic anhydride, glycidyl (meth) acrylate, triallyl isocyanurate, tri (meth) acrylic isocyanurate, and trimethylolpropane tri (meth) acrylate. The composition according to claim 1, which is one or more of the above-mentioned compositions. The composition according to claim 1 or 2, wherein the polar monomer is a bismaleimide having an aromatic ring, and the aromatic ring has one or more groups having 1 or more carbon atoms on the ring. The item according to any one of claims 1 to 3, wherein the amount of the polar monomer is in the range of 0.1 to 30 parts by mass with respect to 100 parts by mass of the total of the copolymer and the polar monomer. The composition described. The copolymer has the following conditions (1) to (4) (1) and the number average molecular weight of the copolymer is 500 or more and 100,000 or less.
(2) The aromatic vinyl compound monomer is an aromatic vinyl compound having 8 or more and 20 or less carbon atoms, and the content of the aromatic vinyl compound monomer unit is 0% by mass or more and 70% by mass or less.
(3) The aromatic polyene is one or more selected from polyenes having a plurality of vinyl groups and / or vinylene groups in the molecule and having 5 or more and 20 or less carbon atoms, and the vinyl group and / or derived from the aromatic polyene unit. The content of vinylene groups is 1.5 or more and less than 20 per number average molecular weight.
(4) The olefin is one or more selected from olefins having 2 or more carbon atoms and 20 or less carbon atoms, and the total of the olefin monomer unit, the aromatic vinyl compound monomer unit and the aromatic polyene monomer unit is 100 mass by mass. %.
The composition according to any one of claims 1 to 4, wherein all of the above are satisfied. Claims 1 to 5, wherein the value obtained by dividing the storage elastic modulus of the cured product of the composition at 25 ° C. by the storage elastic modulus of the cured product of the composition at 250 ° C. is 20 or less. The composition according to any one. Further, any one of claims 1 to 6, further comprising a second monomer, which is one or more selected from the group consisting of an aromatic vinyl compound monomer and an aromatic polyene monomer, and / or a resin. The composition according to the section. The composition according to claim 7, wherein the second monomer and / or the resin is contained in an amount of 300 parts by mass or less based on 100 parts by mass of the copolymer. The composition according to any one of claims 1 to 8, further comprising a curing agent. The composition according to any one of claims 1 to 9, which is curable. A molded product obtained by curing the composition according to any one of claims 1 to 10. The molded product according to claim 11, which is a sheet. The molded product according to claim 11 or 12, which is an electrically insulating material. A laminate containing a layer containing the composition according to any one of claims 1 to 10 and a metal foil. A cured product obtained by curing the laminate according to claim 14. A single-layer CCL, a multi-layer CCL, a single-layer FCCL, or a multi-layer FCCL substrate containing the cured product according to claim 15.