Resin composition, prepreg, laminated plate, printed wiring board, and semiconductor package

Abstract

Provided is a resin composition comprising: (A) one or more selected from the group consisting of a maleimide resin having at least one N-substituted maleimide group and a derivative of the maleimide resin; (B) a modified conjugated diene polymer obtained by modifying a conjugated diene polymer, having a vinyl group in a side chain, with a maleimide resin having at least two N-substituted maleimide groups; and (C) a copolymer resin comprising a structural unit derived from an aromatic vinyl compound and a structural unit derived from an unsaturated aliphatic hydrocarbon, wherein the content of the structural unit derived from the aromatic vinyl compound is less than 30 mass%. Also provided are a prepreg, a laminate, a resin film, a printed wiring board and a semiconductor package using the resin composition.

Description

Resin composition, prepreg, laminate, printed wiring board, and semiconductor package

[0001] The present embodiment relates to a resin composition, a prepreg, a laminate, a printed wiring board, and a semiconductor package.

[0002] The speed and capacity of signals used in electronic devices such as mobile phones, their base station equipment, servers, routers, and other network infrastructure equipment, and large-scale computers are increasing year by year. Accordingly, the substrate materials for the printed wiring boards used in these electronic devices are required to have low dielectric constants and low dielectric loss tangents in order to reduce transmission loss of high-frequency signals.

[0003] For example, Patent Document 1 discloses a thermosetting maleimide resin composition that is varnish-like, does not become cloudy or separate, has excellent dielectric properties, and gives a cured product that has strong adhesive strength even to organic resins such as LCP and MPI and to copper. The thermosetting maleimide resin composition comprises (A) a styrene-based elastomer having reactive functional groups at both ends, (B) a specific maleimide compound, (C) an epoxy resin having two or more epoxy groups in one molecule, and (D) an anionic polymerization initiator catalyst, and the ratio of component (A) to component (B) (mass ratio (A) / (B)) is 2 to 20.

[0004] Japanese Patent Application Laid-Open No. 2023-070764

[0005] In the manufacture of printed wiring boards, stress caused by the difference in thermal expansion coefficient between the substrate and the semiconductor chip during component mounting on the substrate can become a problem. This stress can cause warping of the semiconductor package and reduce reliability. Therefore, there is a demand for insulating materials used in substrates for printed wiring boards with a smaller thermal expansion coefficient.

[0006] In the technology of Patent Document 1, a styrene-based elastomer is used to improve the dielectric properties of the cured product. The inventors have found that the thermal expansion coefficient of the cured resin composition can be reduced by increasing the content of styrene-derived structural units in the styrene-based elastomer. However, this method increases the dielectric loss tangent, making it difficult to achieve both a low dielectric loss tangent and low thermal expansion.

[0007] In view of the current situation, an object of the present embodiment is to provide a resin composition having a low dielectric tangent and excellent low thermal expansion properties, and a prepreg, a laminate, a resin film, a printed wiring board, and a semiconductor package using the resin composition.

[0008] That is, this embodiment provides the following [1] to

[10] . [1] A resin composition containing: (A) one or more maleimide resins having one or more N-substituted maleimide groups and derivatives of the maleimide resin; (B) a modified conjugated diene polymer obtained by modifying a conjugated diene polymer having a vinyl group in its side chain with a maleimide resin having two or more N-substituted maleimide groups; and (C) a copolymer resin containing structural units derived from an aromatic vinyl compound and structural units derived from an unsaturated aliphatic hydrocarbon, the content of the structural units derived from the aromatic vinyl compound being less than 30 mass%. [2] The resin composition according to [1] above, in which the structural units derived from the aromatic vinyl compound contained in the component (C) are structural units derived from styrene. [3] The resin composition according to [1] or [2] above, in which the structural units derived from the unsaturated aliphatic hydrocarbon contained in the component (C) are structural units obtained by hydrogenating structural units formed by addition polymerization of a conjugated diene compound. [4] The resin composition according to any one of [1] to [3] above, wherein the component (B) is a modified conjugated diene polymer obtained by modifying a polybutadiene having a 1,2-vinyl group in its side chain with a maleimide resin having two or more N-substituted maleimide groups. [5] The resin composition according to any one of [1] to [4] above, further comprising (D) an inorganic filler. [6] A prepreg containing the resin composition according to any one of [1] to [5] above or a semi-cured product of the resin composition. [7] A laminate having a cured product of the resin composition according to any one of [1] to [5] above and a metal foil. [8] A resin film containing the resin composition according to any one of [1] to [5] above or a semi-cured product of the resin composition. [9] A printed wiring board having a cured product of the resin composition according to any one of [1] to [5] above.

[10] A semiconductor package having the printed wiring board according to [9] above and a semiconductor element.

[0009] According to the present embodiment, it is possible to provide a resin composition having a low dielectric tangent and excellent low thermal expansion properties, and a prepreg, a laminate, a resin film, a printed wiring board, and a semiconductor package using the resin composition.

[0010] In this specification, a numerical range indicated using "to" indicates a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. For example, a numerical range "X to Y" (X and Y are real numbers) means a numerical range that is equal to or greater than X and equal to or less than Y. In this specification, the term "X or greater" means X and a numerical value that exceeds X. In addition, the term "Y or less" in this specification means Y and a numerical value that is less than Y. The lower limit and upper limit of a numerical range described in this specification can be arbitrarily combined with the lower limit or upper limit of another numerical range. In the numerical ranges described in this specification, the lower limit or upper limit of that numerical range may be replaced with a value shown in the examples.

[0011] Unless otherwise specified, each of the components and materials exemplified in this specification may be used alone or in combination of two or more. In this specification, when a resin composition contains a plurality of substances corresponding to each component, the content of each component in the resin composition means the total amount of the plurality of substances present in the resin composition, unless otherwise specified.

[0012] In this specification, the term "solid content" refers to components other than the solvent, and components that are liquid at 25°C are also considered to be solid content.

[0013] The number average molecular weight (Mn) and weight average molecular weight (Mw) in this specification refer to values ​​measured in terms of polystyrene by gel permeation chromatography (GPC). Specifically, the number average molecular weight (Mn) and weight average molecular weight (Mw) in this specification can be measured by the method described in the examples.

[0014] In this specification, the term "semi-cured product" is synonymous with a resin composition in a B-stage state according to JIS K 6800 (2006), and the term "cured product" is synonymous with a resin composition in a C-stage state according to JIS K 6800 (2006).

[0015] The mechanism of action described in this specification is speculation and does not limit the mechanism by which the effects of this embodiment are achieved.

[0016] Any combination of the features described in this specification is also included in this embodiment.

[0017] [Resin Composition] The resin composition of this embodiment is a resin composition containing: (A) one or more maleimide resins having one or more N-substituted maleimide groups and derivatives of the maleimide resins; (B) a modified conjugated diene polymer obtained by modifying a conjugated diene polymer having a vinyl group in its side chain with a maleimide resin having two or more N-substituted maleimide groups; and (C) a copolymer resin containing structural units derived from an aromatic vinyl compound and structural units derived from an unsaturated aliphatic hydrocarbon, wherein the content of the structural units derived from the aromatic vinyl compound is less than 30 mass%. Note that, in this specification, the individual components may be abbreviated as component (A), component (B), etc., and similar abbreviations may be used for other components.

[0018] Although the details of why the resin composition of this embodiment has a low dielectric tangent and excellent low thermal expansion are unknown, it is speculated as follows. The resin composition of this embodiment contains component (B) and component (C) in addition to component (A), which is a thermosetting resin. Component (C) contains structural units derived from unsaturated aliphatic hydrocarbons that contribute to a low dielectric tangent, making it effective in lowering the dielectric tangent. Furthermore, since the content of structural units derived from aromatic vinyl compounds is less than 30% by mass, stacking of structural units derived from aromatic vinyl compounds is less likely to occur, thereby suppressing an increase in the coefficient of thermal expansion. Furthermore, since component (B) can react with components (A) and (C), the use of component (B) is thought to increase the number of crosslinking points in the cured product and further improve the low thermal expansion. The components contained in the resin composition of this embodiment are described below.

[0019] <Component (A)> The component (A) is at least one selected from the group consisting of maleimide resins having one or more N-substituted maleimide groups and derivatives of such maleimide resins. As the component (A), one type may be used alone, or two or more types may be used in combination.

[0020] In the following description, a maleimide resin having one or more N-substituted maleimide groups may be referred to as a "maleimide resin (AX)" or "(AX) component." Furthermore, a derivative of a maleimide resin having one or more N-substituted maleimide groups may be referred to as a "maleimide resin derivative (AY)" or "(AY) component."

[0021] (Maleimide Resin (AX)) The maleimide resin (AX) is not particularly limited as long as it is a maleimide resin having one or more N-substituted maleimide groups. From the viewpoints of conductor adhesion and heat resistance, however, it is preferably an aromatic maleimide resin having two or more N-substituted maleimide groups, and more preferably an aromatic bismaleimide resin having two N-substituted maleimide groups.

[0022] In this specification, the term "aromatic maleimide resin" refers to a compound having an N-substituted maleimide group directly bonded to an aromatic ring. In addition, in this specification, the term "aromatic bismaleimide resin" refers to a compound having two N-substituted maleimide groups directly bonded to an aromatic ring. In addition, in this specification, the term "aromatic polymaleimide resin" refers to a compound having three or more N-substituted maleimide groups directly bonded to an aromatic ring. In addition, in this specification, the term "aliphatic maleimide resin" refers to a compound having an N-substituted maleimide group directly bonded to an aliphatic hydrocarbon.

[0023] The maleimide resin (AX) is preferably a maleimide resin represented by the following general formula (A-1).

[0024] (In the formula, X Ａ１ is a divalent organic group.

[0025] X in the above general formula (A-1) Ａ１ Examples of the divalent organic group represented by the formula (A-3), (A-4), (A-5), (A-6), or (A-7) below include divalent organic groups represented by the formula (A-2), (A-3), (A-4), (A-5), (A-6), or (A-7) below.

[0026] (In the formula, R Ａ１ is an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom. Ａ１is an integer from 0 to 4. * represents a binding site.)

[0027] R in the above general formula (A-2) Ａ１ Examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by include alkyl groups having 1 to 5 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, and n-pentyl; alkenyl groups having 2 to 5 carbon atoms; and alkynyl groups having 2 to 5 carbon atoms. The aliphatic hydrocarbon group having 1 to 5 carbon atoms may be either linear or branched. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. n Ａ１ is an integer of 2 or more, a plurality of R Ａ１ They may be the same or different.

[0028] (In the formula, R Ａ２ and R Ａ３ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom. Ａ２ n is an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, an ether group, a sulfide group, a sulfonyl group, a carbonyloxy group, a keto group, a single bond, or a divalent organic group represented by the following general formula (A-3-1): Ａ２ and n Ａ３ are each independently an integer of 0 to 4. * represents a binding site.

[0029] R in the above general formula (A-3) Ａ２ and R Ａ３ The aliphatic hydrocarbon group having 1 to 5 carbon atoms and the halogen atom represented by R Ａ１ The same as X in the above general formula (A-3) can be mentioned. Ａ２ Examples of the alkylene group having 1 to 5 carbon atoms represented by X include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, and a 1,5-pentamethylene group. As the alkylene group having 1 to 5 carbon atoms, a methylene group is preferred. Ａ２Examples of the alkylidene group having 2 to 5 carbon atoms represented by include an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group, and an isopentylidene group. Ａ２ or n Ａ３ is an integer of 2 or more, a plurality of R Ａ２ R Ａ３ They may be the same or different from each other.

[0030] X in the above general formula (A-3) Ａ２ The divalent organic group represented by formula (A-3-1) is as follows:

[0031] (In the formula, R Ａ４ and R Ａ５ are each independently an aliphatic hydrocarbon group having 1 to 5 carbon atoms or a halogen atom. Ａ３ is an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, an ether group, a sulfide group, a sulfonyl group, a carbonyloxy group, a keto group, or a single bond. Ａ４ and n Ａ５ are each independently an integer of 0 to 4. * represents a binding site.

[0032] R in the above general formula (A-3-1) Ａ４ and R Ａ５ The aliphatic hydrocarbon group having 1 to 5 carbon atoms and the halogen atom represented by R Ａ１ The same as X in the above general formula (A-3-1) can be mentioned. Ａ３ The alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by the above X Ａ２ The same as those in the above general formula (A-3-1) Ａ４ and n Ａ５ are each independently an integer of 0 to 4, and from the viewpoint of availability, are preferably all integers of 0 to 2. Ａ４ or n Ａ５ is an integer of 2 or more, a plurality of R Ａ４ R Ａ５ They may be the same or different from each other.

[0033] (In the formula, n Ａ６ is an integer from 0 to 10. * represents a binding site.)

[0034] (In the formula, n Ａ７ is a number from 0 to 5. * represents a binding site.)

[0035] (In the formula, R Ａ６ and R Ａ７ are each independently a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms. Ａ８ is an integer from 1 to 8. * represents a binding site.)

[0036] R in the above general formula (A-6) Ａ６ and R Ａ７ The aliphatic hydrocarbon group having 1 to 5 carbon atoms and the halogen atom represented by R Ａ１ The same as those in the general formula (A-6) above are included. Ａ８ is an integer of 2 or more, a plurality of R Ａ６ R Ａ７ They may be the same or different from each other.

[0037] (In the formula, R Ａ８ represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group; n Ａ９ is an integer from 0 to 3. Ａ９ ~R Ａ１１ are each independently an alkyl group having 1 to 10 carbon atoms. Ａ１２ are each independently an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group, or a mercapto group. Ａ１０ are each independently an integer of 0 to 4, Ａ１１is a value between 0.95 and 10.0. * indicates a binding site.)

[0038] R in the above general formula (A-7) Ａ８ Examples of the alkyl group having 1 to 10 carbon atoms represented by R include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a decyl group. These alkyl groups may be either linear or branched. Ａ８ Examples of the alkyl group contained in the alkyloxy group having 1 to 10 carbon atoms and the alkylthio group having 1 to 10 carbon atoms represented by the formula (I) include the same alkyl groups as those having 1 to 10 carbon atoms described above. Ａ８ Examples of the aryl group having 6 to 10 carbon atoms represented by R include a phenyl group and a naphthyl group. Ａ８ Examples of the aryl group contained in the aryloxy group having 6 to 10 carbon atoms and the arylthio group having 6 to 10 carbon atoms represented by the formula (R) include the same as the aryl group having 6 to 10 carbon atoms described above. Ａ８ Examples of the cycloalkyl group having 3 to 10 carbon atoms represented by the formula (I) include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclodecyl group.

[0039] R Ａ９ ~R Ａ１１ The alkyl group having 1 to 10 carbon atoms represented by the formula (I) is the same as the above-mentioned R Ａ８ Among these, R Ａ９ ~R Ａ１１ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Ａ９ is an integer from 0 to 3, and n Ａ９ When R is 2 or 3, multiple R Ａ８ They may be the same or different.

[0040] Among the above, the divalent organic group represented by the general formula (A-7) is preferred from the viewpoints of compatibility with other resins, solvent solubility, dielectric properties, adhesion to conductors, and ease of production. Ａ９ is 0, and R Ａ９~R Ａ１１ is preferably a divalent organic group in which R is a methyl group.

[0041] In the general formula (A-7), multiple R Ａ８ R Ａ１２ Multiple n Ａ９ Multiple n Ａ１０ Each of n may be the same or different. Ａ１１ If R exceeds 1, multiple R Ａ９ R Ａ１０ R Ａ１１ Each of the two may be the same or different.

[0042] R in the above general formula (A-7) Ａ１２ The alkyl group having 1 to 10 carbon atoms, the alkyloxy group having 1 to 10 carbon atoms, the alkylthio group having 1 to 10 carbon atoms, the aryl group having 6 to 10 carbon atoms, the aryloxy group having 6 to 10 carbon atoms, the arylthio group having 6 to 10 carbon atoms, and the cycloalkyl group having 3 to 10 carbon atoms represented by R Ａ８ The same applies to the alkyl group having 1 to 10 carbon atoms, the alkyloxy group having 1 to 10 carbon atoms, the alkylthio group having 1 to 10 carbon atoms, the aryl group having 6 to 10 carbon atoms, the aryloxy group having 6 to 10 carbon atoms, the arylthio group having 6 to 10 carbon atoms, and the cycloalkyl group having 3 to 10 carbon atoms represented by R Ａ１２ From the viewpoints of compatibility with other resins, solvent solubility, dielectric properties, adhesion to conductors, and ease of production, n is preferably an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Ａ１０ is an integer of 0 to 4, and from the viewpoints of compatibility with other resins, solvent solubility, dielectric properties, adhesion to conductors, and ease of production, is preferably an integer of 0 to 3, more preferably 0 or 2. Ａ１１ is preferably 0.98 to 8.0, more preferably 1.0 to 7.0, and even more preferably 1.1 to 6.0, from the viewpoints of compatibility with other resins, solvent solubility, melt viscosity, handleability, and heat resistance.

[0043] Preferred examples of the divalent organic group represented by general formula (A-7) above include a divalent organic group represented by the following general formula (A-7-1), a divalent organic group represented by the following general formula (A-7-2), a divalent organic group represented by the following general formula (A-7-3), and a divalent organic group represented by the following general formula (A-7-4).

[0044] (In the formula, n Ａ１１ is the same as in the above general formula (A-7). * represents a bonding site.

[0045] Examples of the maleimide resin (AX) include aromatic bismaleimide resins, aromatic polymaleimide resins, and aliphatic maleimide resins. Among these, aromatic bismaleimide resins are preferred. Examples of the maleimide resin (AX) include bis(4-maleimidophenyl)methane, m-phenylene bismaleimide, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, 4-methyl-1,3-phenylene bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, polyphenylmethane maleimide, aromatic bismaleimide resins having an indane skeleton, and biphenylaralkyl maleimide resins. Among these, aromatic bismaleimide resins having an indane skeleton are preferred. As the aromatic bismaleimide resins having an indane skeleton, among the maleimide resins represented by the above general formula (A-1), X Ａ１ is preferably a maleimide resin represented by the divalent organic group represented by the above general formula (A-7).

[0046] (Maleimide resin derivative (AY)) As the maleimide resin derivative (AY), an aminomaleimide resin having a structure derived from the above-mentioned maleimide resin (AX) and a structure derived from a diamine compound is preferred. The aminomaleimide resin can be obtained, for example, by Michael addition of the maleimide resin (AX) and a diamine compound. As the diamine compound, for example, the same amine compound having at least two primary amino groups in one molecule as described in JP 2020-200406 A can be used. Among these, 4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 4,4'-[1,3-phenylenebis(1-methylethylidene)]bisaniline, 4,4'-[1,4-phenylenebis(1-methylethylidene)]bisaniline, and 3,3'-diethyl-4,4'-diaminodiphenylmethane are preferred.

[0047] The content of component (A) in the resin composition of this embodiment is preferably 5 to 90% by mass, more preferably 10 to 60% by mass, and even more preferably 30 to 50% by mass, based on the total amount (100% by mass) of the resin components in the resin composition of this embodiment. When the content of component (A) is equal to or greater than the above-mentioned lower limit, the heat resistance, moldability, processability, and conductor adhesion tend to be improved. Furthermore, when the content of component (A) is equal to or less than the above-mentioned upper limit, the dielectric properties tend to be improved.

[0048] Here, in this specification, the term "resin component" refers to a resin and a compound that forms a resin through a curing reaction. In the resin composition of this embodiment, for example, the components (A), (B), and (C) correspond to the resin component. When the resin composition of this embodiment contains, as optional components, a resin or a compound that forms a resin through a curing reaction in addition to the above components, these optional components are also included in the resin component. On the other hand, the components (D), (E), and (F) are not included in the resin component.

[0049] The total content of the resin components in the resin composition of this embodiment is preferably 10 to 70 mass%, more preferably 20 to 60 mass%, and even more preferably 30 to 50 mass%, relative to the total solid content (100 mass%) of the resin composition of this embodiment, from the viewpoints of low thermal expansion, heat resistance, flame retardancy, and conductor adhesion.

[0050] From the viewpoint of further improving the dielectric properties and low thermal expansion, the total content of the components (A), (B), and (C) in the resin components contained in the resin composition of this embodiment is preferably 60 to 100 mass%, more preferably 80 to 100 mass%, even more preferably 90 to 100 mass%, and still more preferably 95 to 100 mass%, relative to the resin components (100 mass%).

[0051] <Component (B)> Component (B) is a modified conjugated diene polymer obtained by modifying a conjugated diene polymer having a vinyl group in its side chain (hereinafter, sometimes referred to as a "vinyl group-containing conjugated diene polymer") with a maleimide resin having two or more N-substituted maleimide groups (hereinafter, sometimes referred to as a "modifying maleimide resin"). By including component (B), the resin composition of this embodiment tends to have good heat resistance and low thermal expansion, while also easily achieving better dielectric properties. One type of component (B) may be used alone, or two or more types may be used in combination.

[0052] (Vinyl Group-Containing Conjugated Diene Polymer) The vinyl group-containing conjugated diene polymer contains structural units derived from a conjugated diene compound. Examples of conjugated diene compounds include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, and 1,3-hexadiene. Among these, 1,3-butadiene is preferred. The vinyl group-containing conjugated diene polymer may be a polymer of one type of conjugated diene compound, or a copolymer of two or more types of conjugated diene compounds. Furthermore, the vinyl group-containing conjugated diene polymer may be a copolymer of one or more types of conjugated diene compounds and one or more types of monomers other than conjugated diene compounds. When the vinyl group-containing conjugated diene polymer is a copolymer, the polymerization mode may be any of random polymerization, block polymerization, and graft polymerization.

[0053] From the viewpoints of compatibility with other resins and dielectric properties, the number of side chain vinyl groups that the vinyl group-containing conjugated diene polymer has in one molecule is preferably 2 to 100, more preferably 5 to 80, and even more preferably 10 to 60. From the viewpoints of compatibility with other resins, dielectric properties, low thermal expansion, and heat resistance of the resulting modified conjugated diene polymer, the number average molecular weight (Mn) of the vinyl group-containing conjugated diene polymer is preferably 500 to 4,000, more preferably 600 to 3,000, even more preferably 800 to 2,000, and still more preferably 900 to 1,500.

[0054] Examples of vinyl group-containing conjugated diene polymers include polybutadiene having 1,2-vinyl groups in its side chains and butadiene-styrene copolymers having 1,2-vinyl groups in its side chains. Among these, polybutadiene having 1,2-vinyl groups in its side chains is preferred. That is, component (B) is preferably a modified conjugated diene polymer obtained by modifying polybutadiene having 1,2-vinyl groups in its side chains with a maleimide resin having two or more N-substituted maleimide groups. In the polybutadiene having 1,2-vinyl groups, the content of structural units having 1,2-vinyl groups relative to all butadiene-derived structural units constituting the polybutadiene [hereinafter, sometimes referred to as the "vinyl group content"] is preferably 50 to 100 mol %, more preferably 70 to 95 mol %, and even more preferably 85 to 90 mol %, from the viewpoints of compatibility with other resins, dielectric properties, and heat resistance.

[0055] (Maleimide Resin for Modification) As the maleimide resin for modification, for example, a maleimide resin having two or more N-substituted maleimide groups as explained as component (A) can be used, and the same applies to preferred embodiments.

[0056] The component (B) preferably has, in its side chain, a substituent formed by reaction between a side-chain vinyl group of the conjugated diene polymer having a vinyl group in its side chain and an N-substituted maleimide group of the modifying maleimide resin [hereinafter, this may be referred to as a "maleimide resin-derived substituent"], and more preferably has, in its side chain, a maleimide resin-derived substituent and a vinyl group.

[0057] The maleimide resin-derived substituent is preferably a group containing a structure represented by the following general formula (B-1) or (B-2) as a structure derived from the maleimide resin for modification.

[0058] (In the formula, X Ｂ１ is a divalent group obtained by removing two N-substituted maleimide groups from the modifying maleimide resin, and * Ｂ１ is a bonded site to a carbon atom derived from a vinyl group in a side chain of a conjugated diene polymer having a vinyl group in the side chain. Ｂ２ is the site of attachment to another atom.)

[0059] From the viewpoints of compatibility with other resins, dielectric properties, low thermal expansion, and heat resistance, the number average molecular weight (Mn) of component (B) is preferably 700 to 6,000, more preferably 800 to 5,000, and even more preferably 1,000 to 2,500.

[0060] Component (B) can be produced by reacting a conjugated diene polymer having a vinyl group in its side chain with a modifying maleimide resin. Specifically, for example, component (B) can be obtained by charging a conjugated diene polymer having a vinyl group in its side chain, a modifying maleimide resin, a reaction catalyst, and an organic solvent into a reaction vessel and reacting the mixture while heating, keeping the temperature, stirring, etc. as necessary. The reaction conditions for the above reaction may be, for example, a reaction temperature of 70 to 120°C and a reaction time of 0.5 to 15 hours.

[0061] As the reaction catalyst, an organic peroxide is preferred from the viewpoint of obtaining sufficient reactivity while suppressing gelation of the product during the reaction. As the organic peroxide, those exemplified as component (F) described below can be used.

[0062] When the above reaction is carried out, the number of moles of the side chain vinyl groups of the conjugated diene polymer having vinyl groups in the side chains (M ｖ ) 、 The number of moles of N-substituted maleimide groups in the modifying maleimide resin (M ｍ ) ratio (M ｍ / M ｖ ) is preferably 0.0005 to 0.1, more preferably 0.001 to 0.05, and even more preferably 0.002 to 0.01, from the viewpoints of compatibility of the modified conjugated diene polymer with other resins and suppression of gelation of the product.

[0063] The content of component (B) in the resin composition of this embodiment is preferably 5 to 50 mass%, more preferably 10 to 40 mass%, and even more preferably 15 to 30 mass%, based on the total amount (100 mass%) of resin components in the resin composition. When the content of component (B) is equal to or greater than the above-mentioned lower limit, the dielectric properties tend to be better. On the other hand, when the content of component (B) is equal to or less than the above-mentioned upper limit, the heat resistance and flame retardancy tend to be better.

[0064] The content of component (B) in the resin composition of this embodiment is preferably 20 to 100 parts by mass, more preferably 30 to 80 parts by mass, and even more preferably 40 to 60 parts by mass, per 100 parts by mass of component (A). When the content of component (B) is equal to or greater than the above-mentioned lower limit, the dielectric properties tend to be better. On the other hand, when the content of component (B) is equal to or less than the above-mentioned upper limit, the heat resistance and flame retardancy tend to be better.

[0065] <Component (C)> Component (C) is a copolymer resin containing structural units derived from an aromatic vinyl compound and structural units derived from an unsaturated aliphatic hydrocarbon, with the content of the structural units derived from the aromatic vinyl compound being less than 30 mass%. By including component (C), the resin composition of this embodiment achieves both a low dielectric loss tangent and low thermal expansion. One type of component (C) may be used alone, or two or more types may be used in combination.

[0066] The structural unit derived from an aromatic vinyl compound contained in the component (C) is preferably a structural unit represented by the following general formula (C-1).

[0067] (In the formula, R Ｃ１ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R Ｃ２ is an alkyl group having 1 to 5 carbon atoms. Ｃ１ is an integer from 0 to 5.

[0068] R in the above general formula (C-1) Ｃ１ and R Ｃ２Examples of the alkyl group having 1 to 5 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, etc. The alkyl group having 1 to 5 carbon atoms may be either linear or branched. Among these, an alkyl group having 1 to 3 carbon atoms is preferred, an alkyl group having 1 or 2 carbon atoms is more preferred, and a methyl group is even more preferred. In the above general formula (C-1), n Ｃ１ is an integer of 0 to 5, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.

[0069] Among the structural units shown above, the structural unit derived from an aromatic vinyl compound contained in component (C) is preferably a structural unit derived from styrene.

[0070] The structural unit derived from an unsaturated aliphatic hydrocarbon contained in component (C) is preferably a structural unit derived from a conjugated diene compound. Examples of conjugated diene compounds include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, and 1,3-hexadiene. The structural unit derived from a conjugated diene compound may be one type alone or two or more types. Among these, 1,3-butadiene and isoprene are preferred as the conjugated diene compound, and 1,3-butadiene is more preferred.

[0071] The structural units derived from unsaturated aliphatic hydrocarbons are preferably structural units obtained by hydrogenating structural units formed by addition polymerization of a conjugated diene compound. When hydrogenated, the structural units derived from 1,3-butadiene are structural units in which ethylene units and butylene units are mixed, and the structural units derived from isoprene are structural units in which ethylene units and propylene units are mixed.

[0072] Examples of component (C) include hydrogenated styrene-butadiene-styrene block copolymers and hydrogenated styrene-isoprene-styrene block copolymers. Examples of hydrogenated styrene-butadiene-styrene block copolymers include styrene-ethylene-butylene-styrene block copolymers (SEBS) obtained by completely hydrogenating the carbon-carbon double bonds in the butadiene block, and styrene-butadiene-butylene-styrene block copolymers (SBBS) obtained by partially hydrogenating the carbon-carbon double bonds at 1,2-bond sites in the butadiene block. Complete hydrogenation in SEBS typically refers to a hydrogenation rate of the total carbon-carbon double bonds of 90% or more, or may be 95% or more, 99% or more, or even 100%. The partial hydrogenation rate in SBBS is, for example, 60 to 85% of the total carbon-carbon double bonds. The hydrogenated product of the styrene-isoprene-styrene block copolymer is obtained by hydrogenating the polyisoprene block and as a styrene-ethylene-propylene-styrene block copolymer (SEPS). Among these, SEBS and SEPS are preferred, with SEBS being more preferred, from the viewpoints of dielectric properties, conductor adhesion, heat resistance, glass transition temperature, and low thermal expansion.

[0073] The content of structural units derived from aromatic vinyl compounds in component (C) is less than 30% by mass. When the content of structural units derived from aromatic vinyl compounds in component (C) is less than 30% by mass, a resin composition having a low dielectric tangent and excellent low thermal expansion properties can be obtained. From the same viewpoint, the content of structural units derived from aromatic vinyl compounds in component (C) is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less. Furthermore, the content of structural units derived from aromatic vinyl compounds in component (C) is preferably 5% by mass or more, more preferably 7% by mass or more, even more preferably 8% by mass or more, and even more preferably 10% by mass or more. Furthermore, the content of structural units derived from aromatic vinyl compounds in component (C) is preferably 5% by mass or more but less than 30% by mass, more preferably 7 to 25% by mass, even more preferably 8 to 20% by mass, and even more preferably 10 to 15% by mass. When the content of structural units derived from aromatic vinyl compounds in component (C) is at least the above lower limit, the fluidity does not become too high and good moldability is easily obtained, and the heat resistance tends to be better.

[0074] From the viewpoint of achieving a better balance between low dielectric tangent and heat resistance, the total content of the structural units derived from aromatic vinyl compounds and the structural units derived from unsaturated aliphatic hydrocarbons in component (C) is preferably 80 to 100% by mass, more preferably 90 to 100% by mass, and even more preferably 95 to 100% by mass.

[0075] The content of component (C) in the resin composition of this embodiment is preferably 1 to 60 mass%, more preferably 10 to 55 mass%, even more preferably 20 to 50 mass%, and even more preferably 30 to 45 mass%, relative to the total amount (100 mass%) of resin components in the resin composition of this embodiment. When the content of component (C) is equal to or greater than the above-mentioned lower limit, the dielectric properties tend to be better. On the other hand, when the content of component (C) is equal to or less than the above-mentioned upper limit, the heat resistance tends to be better.

[0076] The content of component (C) in the resin composition of this embodiment is preferably 20 to 200 parts by mass, more preferably 50 to 150 parts by mass, and even more preferably 80 to 100 parts by mass, per 100 parts by mass of component (A). When the content of component (C) is equal to or greater than the above-mentioned lower limit, the dielectric properties tend to be better. On the other hand, when the content of component (C) is equal to or less than the above-mentioned upper limit, the heat resistance and flame retardancy tend to be better.

[0077] <(D) Inorganic Filler> The resin composition of this embodiment preferably further contains (D) an inorganic filler. By containing (D) an inorganic filler, the resin composition of this embodiment tends to have better low thermal expansion properties and heat resistance. One type of (D) inorganic filler may be used alone, or two or more types may be used in combination.

[0078] (D) inorganic filler can be enumerated as follows: silica, alumina, titanium oxide, mica, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay, talc, aluminum borate, silicon carbide etc.Among these, from the viewpoint of low thermal expansion, heat resistance and flame retardancy, silica, alumina, mica, talc are preferred, silica, alumina are more preferred, and silica is even more preferred.As silica, from the viewpoint of dispersibility and moldability, fused silica is preferred.

[0079] (D) Average particle diameter of inorganic filler (D ５０ From the viewpoint of dispersibility of the inorganic filler (D) and fine wiring properties, the average particle diameter (D) of the inorganic filler (D) is preferably 0.1 to 10 μm, more preferably 0.2 to 1 μm, and even more preferably 0.3 to 0.8 μm. ５０ The average particle size of the inorganic filler (D) can be measured, for example, by a particle size distribution analyzer using a laser diffraction scattering method.

[0080] The shape of the (D) inorganic filler may be, for example, spherical or crushed, with spherical being preferred. The (D) inorganic filler may be surface-treated with a surface treatment agent such as a silane coupling agent in order to improve dispersibility and adhesion to the organic component.

[0081] When the resin composition of this embodiment contains an inorganic filler (D), the content of the inorganic filler (D) is preferably 20 to 90% by mass, more preferably 30 to 80% by mass, and even more preferably 40 to 60% by mass, based on the total solids content (100% by mass) of the resin composition. When the content of the inorganic filler (D) is equal to or greater than the above-mentioned lower limit, low thermal expansion and heat resistance tend to be more favorable. On the other hand, when the content of the inorganic filler (D) is equal to or less than the above-mentioned upper limit, moldability and conductor adhesion tend to be more favorable.

[0082] <(E) Flame Retardant> The resin composition of this embodiment preferably further contains a flame retardant (E). By containing the flame retardant (E), the resin composition of this embodiment tends to have better flame retardancy. One type of (E) flame retardant may be used alone, or two or more types may be used in combination.

[0083] Examples of (E) flame retardants include phosphorus-based flame retardants, metal hydrates, and halogen-based flame retardants. The phosphorus-based flame retardant may be an inorganic phosphorus-based flame retardant or an organic phosphorus-based flame retardant. From the viewpoint of reducing environmental impact, it is preferable that the phosphorus-based flame retardant does not contain halogen atoms. Examples of inorganic phosphorus-based flame retardants include red phosphorus; ammonium phosphates such as monoammonium phosphate, diammonium phosphate, triammonium phosphate, and ammonium polyphosphate; inorganic nitrogen-containing phosphorus compounds such as phosphoric acid amide; phosphoric acid; and phosphine oxide. Examples of organic phosphorus-based flame retardants include aromatic phosphate ester compounds, monosubstituted phosphonic acid diester compounds, disubstituted phosphinic acid ester compounds, metal salts of disubstituted phosphinic acids, organic nitrogen-containing phosphorus compounds, and cyclic organic phosphorus compounds. Among these, aromatic phosphate ester compounds and metal salts of disubstituted phosphinic acids are preferred. Examples of metal hydrates include aluminum hydroxide hydrate and magnesium hydroxide hydrate. Examples of halogen-based flame retardants include chlorine-based flame retardants, bromine-based flame retardants, etc. Among the above flame retardants, metal salts of disubstituted phosphinic acids are preferred, and aluminum trisdiethylphosphinate is more preferred.

[0084] When the resin composition of this embodiment contains a flame retardant (E), the content of the flame retardant (E) is preferably 1 to 40 mass%, more preferably 5 to 30 mass%, and even more preferably 10 to 20 mass%, based on the total solids content (100 mass%) of the resin composition. When the content of the flame retardant (E) is equal to or greater than the above-mentioned lower limit, the flame retardancy tends to be better. On the other hand, when the content of the flame retardant (E) is equal to or less than the above-mentioned upper limit, the dielectric properties, moldability, and conductor adhesion tend to be better.

[0085] <(F) Curing Accelerator> The resin composition of this embodiment preferably further contains a (F) curing accelerator. By containing the (F) curing accelerator, the resin composition of this embodiment tends to have improved curability and better dielectric properties, heat resistance, and conductor adhesion. One type of (F) curing accelerator may be used alone, or two or more types may be used in combination.

[0086] Examples of the (F) curing accelerator include acidic catalysts such as p-toluenesulfonic acid; amine compounds such as triethylamine, tributylamine, pyridine, and dicyandiamide; imidazole compounds such as methylimidazole, phenylimidazole, 2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-phenylimidazolium trimellitate; isocyanate-masked imidazole compounds such as the addition reaction product of hexamethylene diisocyanate resin and 2-ethyl-4-methylimidazole; quaternary ammonium compounds; and phosphorus compounds such as triphenylphosphine and quaternary phosphonium compounds which are addition reaction products of p-benzoquinone and tri-n-butylphosphine. peroxides such as dicumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexyne-3, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, t-butylperoxyisopropyl monocarbonate, and α,α'-bis(t-butylperoxy)diisopropylbenzene; inorganic peroxides such as potassium persulfate, sodium persulfate, and ammonium persulfate; azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(4-methoxy-2'-dimethylvaleronitrile); carboxylates of manganese, cobalt, zinc, and the like; and acidic catalysts such as p-toluenesulfonic acid. Among these, from the viewpoints of curing acceleration effect and storage stability, imidazole compounds, isocyanate-masked imidazole compounds, organic peroxides, and carboxylates are preferred, organic peroxides are more preferred, and dicumyl peroxide is even more preferred.

[0087] When the resin composition of this embodiment contains a (F) curing accelerator, the content of the (F) curing accelerator is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 7 parts by mass, and even more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the (A) component. When the content of the (F) curing accelerator is equal to or greater than the above-mentioned lower limit, a sufficient curing acceleration effect tends to be easily obtained. Furthermore, when the content of the (F) curing accelerator is equal to or less than the above-mentioned upper limit, storage stability tends to be more easily improved.

[0088] <Other Optional Components> The resin composition of the present embodiment may further contain other optional components, such as resin materials other than the above components, flame retardants, antioxidants, heat stabilizers, antistatic agents, UV absorbers, pigments, colorants, lubricants, silane coupling agents, organic solvents, and other additives, as needed. Each of the other optional components may be used alone, or two or more may be used in combination. The content of the above optional components in the resin composition of the present embodiment is not particularly limited, and they may be used as needed within a range that does not impair the effects of the present embodiment. Furthermore, the resin composition of the present embodiment may not contain the above optional components, depending on the desired performance.

[0089] (Organic Solvent) The resin composition of this embodiment may contain an organic solvent from the viewpoint of handleability. In this specification, a resin composition containing an organic solvent may be referred to as a resin varnish. Examples of organic solvents include alcohol-based solvents such as ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve, and propylene glycol monomethyl ether; ketone-based solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ether-based solvents such as tetrahydrofuran; aromatic hydrocarbon-based solvents such as toluene, xylene, and mesitylene; nitrogen-containing solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; sulfur-containing solvents such as dimethyl sulfoxide; and ester-based solvents such as γ-butyrolactone. Among these, from the viewpoint of solubility, alcohol-based solvents, ketone-based solvents, nitrogen-containing solvents, and aromatic hydrocarbon-based solvents are preferred, aromatic hydrocarbon-based solvents are more preferred, and toluene is even more preferred.

[0090] <Method for producing resin composition> The resin composition of this embodiment can be produced by mixing the respective components. At this time, the respective components may be dissolved or dispersed while stirring. The conditions such as the mixing order, temperature, and time are not particularly limited and may be set as desired depending on the types of raw materials, etc.

[0091] [Prepreg] The prepreg of the present embodiment is a prepreg containing the resin composition of the present embodiment or a semi-cured product of the resin composition. The prepreg of the present embodiment contains, for example, the resin composition of the present embodiment or a semi-cured product of the resin composition and a sheet-like fiber base material.

[0092] The sheet-like fiber substrate contained in the prepreg of this embodiment can be, for example, a known sheet-like fiber substrate used in various laminates for electrical insulating materials. Examples of the material for the sheet-like fiber substrate include inorganic fibers such as E-glass, D-glass, S-glass, and Q-glass; organic fibers such as polyimide, polyester, and tetrafluoroethylene; and mixtures thereof. These sheet-like fiber substrates have shapes such as woven fabric, nonwoven fabric, roving, chopped strand mat, and surfacing mat.

[0093] The prepreg of this embodiment can be produced, for example, by impregnating or applying the resin composition of this embodiment to a sheet-like fiber substrate, and then heating and drying the composition to B-stage. The temperature and time for heating and drying can be, for example, 50 to 200°C and 1 to 30 minutes, from the viewpoints of productivity and appropriately B-staging the resin composition of this embodiment.

[0094] The solids concentration derived from the resin composition in the prepreg of the present embodiment is preferably 20 to 90 mass%, more preferably 25 to 80 mass%, and even more preferably 30 to 75 mass%, from the viewpoint that better moldability is easily obtained when the prepreg is made into a laminate.

[0095] [Resin Film] The resin film of this embodiment is a resin film containing the resin composition of this embodiment or a semi-cured product of the resin composition. The resin film of this embodiment can be produced, for example, by applying the resin composition of this embodiment containing an organic solvent, i.e., a resin varnish, to a support and then heating and drying. Examples of the support include plastic film, metal foil, and release paper. The temperature and time for heating and drying can be 50 to 200°C and 1 to 30 minutes, from the viewpoints of productivity and appropriately B-staging the resin composition of this embodiment.

[0096] The resin film of this embodiment is preferably used to form an insulating layer when producing a printed wiring board.

[0097] [Laminate] The laminate of the present embodiment is a laminate having a cured product of the resin composition of the present embodiment and a metal foil. Note that a laminate having a metal foil is sometimes called a metal-clad laminate.

[0098] The metal of the metal foil is not particularly limited, and examples thereof include copper, gold, silver, nickel, platinum, molybdenum, ruthenium, aluminum, tungsten, iron, titanium, chromium, and alloys containing one or more of these metal elements.

[0099] The laminate of this embodiment can be produced, for example, by placing metal foil on one or both sides of the prepreg of this embodiment and then hot-press molding. Typically, the B-staged prepreg is cured by this hot-press molding to obtain the laminate of this embodiment. When hot-press molding, only one prepreg may be used, or two or more prepregs may be laminated together. Hot-press molding can be performed using, for example, a multi-stage press, a multi-stage vacuum press, a continuous molding machine, an autoclave molding machine, or the like. Hot-press molding conditions can be, for example, a temperature of 100 to 300°C, a time of 10 to 300 minutes, and a pressure of 1.5 to 5 MPa.

[0100] [Printed Wiring Board] The printed wiring board of this embodiment is a printed wiring board having a cured product of the resin composition of this embodiment. The printed wiring board of this embodiment can be produced, for example, by forming a conductor circuit on one or more materials selected from the group consisting of a cured product of the prepreg of this embodiment, a cured product of the resin film of this embodiment, and a laminate by a known method. Furthermore, a multilayer printed wiring board can also be produced by further performing a multilayer adhesive process as necessary. The conductor circuit can be formed, for example, by appropriately performing drilling, metal plating, etching of metal foil, etc.

[0101] [Semiconductor Package] The semiconductor package of this embodiment is a semiconductor package including the printed wiring board of this embodiment and a semiconductor element. The semiconductor package of this embodiment can be manufactured, for example, by mounting a semiconductor chip, a memory, etc. on the printed wiring board of this embodiment by a known method.

[0102] The present embodiment will be specifically described below with reference to examples, although the present embodiment is not limited to the following examples.

[0103] [Method for measuring number average molecular weight (Mn)] The number average molecular weight (Mn) was calculated by gel permeation chromatography (GPC) from a calibration curve using standard polystyrene. The calibration curve was approximated by a cubic equation using standard polystyrene: TSKstandard POLYSTYRENE (Types: A-2500, A-5000, F-1, F-2, F-4, F-10, F-20, F-40) [manufactured by Tosoh Corporation, trade name]. The GPC measurement conditions are shown below. Apparatus: Pump: L-6200 type [manufactured by Hitachi High-Technologies Corporation] Detector: L-3300 type RI [manufactured by Hitachi High-Technologies Corporation] Column oven: L-655A-52 [manufactured by Hitachi High-Technologies Corporation] Column: Guard column; TSK Guard column HHR-L + column; TSKgel G4000HHR + TSKgel G2000HHR (all manufactured by Tosoh Corporation, trade names) Column size: 6.0 x 40 mm (guard column), 7.8 x 300 mm (column) Eluent: tetrahydrofuran Sample concentration: 30 mg / 5 mL Injection volume: 20 μL Flow rate: 1.00 mL / min Measurement temperature: 40°C

[0104] [Production of Modified Conjugated Diene Polymer] Production Example 1 Into a 2 L glass flask equipped with a thermometer, a reflux condenser, and a stirrer and capable of heating and cooling, 100 parts by mass of polybutadiene (1,2-polybutadiene homopolymer, number average molecular weight (Mn) 1,200, vinyl group content = 85 mol% or more), 4.4 parts by mass of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 0.1 parts by mass of α,α'-bis(t-butylperoxy)diisopropylbenzene, and toluene as an organic solvent were added. Subsequently, the mixture was reacted under a nitrogen atmosphere at 90 to 100°C for 5 hours with stirring to obtain a solution of a modified conjugated diene polymer (solids concentration: 35% by mass).

[0105] [Production of Resin Composition] Example 1, Comparative Examples 1 and 2 Each component shown in Table 1 was blended with toluene according to the formulation shown in Table 1, and the blended mixture was stirred and mixed at 25° C. to prepare a resin varnish having a solid content concentration of 60% by mass. In Table 1, the unit of the blend amount of each component is parts by mass, and in the case of a solution, it means parts by mass converted into solid content.

[0106] (Production of Prepreg) The resin varnish prepared in each example was impregnated into a glass cloth (manufactured by Nitto Boseki Co., Ltd., #1078 type), and then heated and dried at 120°C for 5 minutes to obtain a prepreg with a resin composition content of 66 mass%.

[0107] (Production of copper-clad laminate) Nine prepregs obtained above were stacked, and 18 μm thick copper foil (manufactured by Mitsui Kinzoku Co., Ltd., product name "3EC-M3-VLP-12", roughened surface Rz: 3.0 μm) was placed on top and bottom of them so that the roughened surface was in contact with the prepreg. This laminate was heated and press-molded at a temperature of 180°C, a pressure of 3.0 MPa, and a time of 60 minutes to produce a copper-clad laminate.

[0108] [Evaluation Method] Each evaluation was carried out according to the following methods. The results are shown in Table 1.

[0109] (Method for measuring relative permittivity (Dk) and dielectric loss tangent (Df)) The copper-clad laminate prepared in each example was immersed in a 10% by mass solution of ammonium persulfate (manufactured by Mitsubishi Gas Chemical Company, Inc.), which is a copper etching solution, to remove the copper foil. The obtained resin plate was cut into a 2 mm x 50 mm piece and dried at 105°C for 1 hour to prepare a test piece. Next, the relative permittivity (Dk) and dielectric loss tangent (Df) of the test piece were measured at an ambient temperature of 25°C and in the 10 GHz band according to the cavity resonator perturbation method.

[0110] (Method for measuring thermal expansion coefficient) The copper foil on both sides of the copper-clad laminate prepared in each example was removed by etching to prepare a 5 mm square test piece. Next, the test piece was mounted on a thermomechanical analyzer (TMA) (manufactured by TA Instruments Japan, product name "Q400"), and thermomechanical analysis was performed twice consecutively using a compression method under the conditions of a temperature range of 30 to 260 ° C, a load of 5 g, and a heating rate of 10 ° C / min. The thermal expansion coefficient was the average thermal expansion coefficient from 30 to 120 ° C in the second measurement. Note that the thermal expansion coefficient is the thermal expansion coefficient in the "thickness direction" of the laminate.

[0111]

[0112] Details of each component listed in Table 1 are as follows: [Component (A)] Maleimide resin: aromatic bismaleimide resin having a group containing an indane ring: number average molecular weight (Mn) 1,300

[0113] [Component (B)] Modified conjugated diene polymer: modified conjugated diene polymer obtained in Production Example 1

[0114] [Component (C)] H1221: styrene-ethylene-butylene-styrene block copolymer (SEBS), manufactured by Asahi Kasei Corporation, product name "Tuftec (registered trademark) H1221", content of structural units derived from aromatic vinyl compounds (styrene): 12% by mass, number average molecular weight (Mn) = 170,000

[0115] [Component (C')] H1041: styrene-ethylene-butylene-styrene block copolymer (SEBS), manufactured by Asahi Kasei Corporation, trade name "Tuftec (registered trademark) H1041", content of structural units derived from aromatic vinyl compounds (styrene): 30 mass%, number average molecular weight (Mn): 101,300 H1043: styrene-ethylene-butylene-styrene block copolymer (SEBS), manufactured by Asahi Kasei Corporation, trade name "Tuftec (registered trademark) H1043", content of structural units derived from aromatic vinyl compounds (styrene): 67 mass%

[0116] [Component (D)] Silica: fused spherical silica, average particle diameter (D ５０ ): 0.5 μm

[0117] [Component (E)] Flame retardant: aluminum trisdiethylphosphinate

[0118] [Component (F)] Curing accelerator: dicumyl peroxide

[0119] From the results shown in Table 1, it can be seen that the resin composition of Example 1 of this embodiment has a low dielectric tangent and is excellent in low thermal expansion.

Claims

1. A resin composition comprising: (A) one or more members selected from the group consisting of maleimide resins having one or more N-substituted maleimide groups and derivatives of said maleimide resins; (B) a modified conjugated diene polymer obtained by modifying a conjugated diene polymer having a vinyl group in its side chain with a maleimide resin having two or more N-substituted maleimide groups; and (C) a copolymer resin which contains structural units derived from an aromatic vinyl compound and structural units derived from an unsaturated aliphatic hydrocarbon, the content of said structural units derived from an aromatic vinyl compound being less than 30 mass%.

2. The resin composition according to claim 1, wherein the structural unit derived from an aromatic vinyl compound contained in component (C) is a structural unit derived from styrene.

3. A resin composition according to claim 1 or 2, wherein the structural unit derived from an unsaturated aliphatic hydrocarbon contained in the component (C) is a structural unit obtained by hydrogenating a structural unit formed by addition polymerization of a conjugated diene compound.

4. The resin composition according to claim 1 or 2, wherein the component (B) is a modified conjugated diene polymer obtained by modifying a polybutadiene having a 1,2-vinyl group in the side chain with a maleimide resin having two or more N-substituted maleimide groups.

5. The resin composition according to claim 1 or 2, further comprising (D) an inorganic filler.

6. A prepreg containing the resin composition according to claim 1 or 2 or a semi-cured product of said resin composition.

7. A laminate comprising a cured product of the resin composition according to claim 1 or 2 and a metal foil.

8. A resin film comprising the resin composition according to claim 1 or 2 or a semi-cured product of said resin composition.

9. A printed wiring board having a cured product of the resin composition according to claim 1 or 2.

10. A semiconductor package comprising the printed wiring board according to claim 9 and a semiconductor element.

Images