JP7639869B2 - Resin composition - Google Patents

Description

The present invention relates to a resin composition. Furthermore, the present invention relates to a resin sheet, a printed wiring board, and a semiconductor device obtained by using the resin composition.

A printed wiring board is generally provided with an insulating layer, which is formed by curing a resin composition. For example, the resin composition disclosed in Patent Document 1 is known as such a resin composition.

JP 2019-66792 A

In recent years, there has been a demand for insulating layers with a high biomass ratio from the perspective of environmental protection and carbon neutrality.

However, when an insulating layer is formed using a resin composition with a high biomass ratio using a resin component derived from biomass, the peel strength between the conductor layer can decrease and the insulation reliability can be poor.

The present invention was devised in view of the above problems, and aims to provide a resin composition that produces a cured product with high peel strength and excellent insulation reliability even when the biomass ratio of the resin component in the resin composition is high; a resin sheet having a resin composition layer containing the resin composition; a printed wiring board including an insulating layer formed of a cured product of the resin composition; and a semiconductor device including the printed wiring board.

After extensive research, the inventors have found that when the biomass ratio of resin components including (A) thermosetting resin and (B) thermoplastic resin is increased, peel strength is reduced and insulation reliability is deteriorated. Although this does not limit the technical scope of the present invention, it is presumed that the above-mentioned decrease in peel strength and insulation reliability occurs because biomass-derived resin components can unavoidably contain impurities and because biomass-derived resin components tend to have a relatively flexible molecular structure because they exist in living organisms. As a result of extensive research to solve the above-mentioned problems, the inventors have found that the above-mentioned problems can be solved even if the biomass ratio of the resin components is increased by adjusting the contents of the (A) and (B) components to be within a predetermined range and adjusting the (A) and (B) components so that the biomass ratio of the liquid resin in the resin components is 40 mass% or less, and have completed the present invention.

That is, the present invention includes the following.
[1] A resin composition comprising: (A) a thermosetting resin; and (B) a thermoplastic resin,
The content of the component (A) is 10% by mass or more when the total amount of non-volatile components in the resin composition is 100% by mass,
The content of the (B) component is 10% by mass or less, when the total amount of non-volatile components in the resin composition is 100% by mass,
The biomass ratio of the resin component in the resin composition is 5% by mass or more,
A resin composition, wherein a biomass ratio of a liquid resin in a resin component is 40 mass% or less.
[2] The resin composition according to [1], further comprising (C) an inorganic filler.
[3] The resin composition according to [2], wherein the content of the inorganic filler (C) is 20% by mass or more when the non-volatile components in the resin composition are 100% by mass.
[4] The resin composition according to any one of [1] to [3], wherein the thermosetting resin (A) contains an epoxy resin (A-1).
[5] The resin composition according to any one of [1] to [4], wherein the thermosetting resin (A) contains a curing agent (A-2).
[6] The resin composition according to any one of [1] to [5], wherein the liquid resin contains either (A-1) an epoxy resin or (A-2) a curing agent.
[7] The resin composition according to any one of [1] to [6], which is for forming an insulating layer.
[8] A resin sheet comprising a support and a resin composition layer provided on the support, the resin composition layer comprising the resin composition according to any one of [1] to [7].
[9] A printed wiring board comprising an insulating layer formed from a cured product of the resin composition according to any one of [1] to [7].
[10] A semiconductor device comprising the printed wiring board according to [9].

According to the present invention, it is possible to provide a resin composition that produces a cured product with high peel strength and excellent insulation reliability even when the biomass ratio of the resin component is increased; a resin sheet having a resin composition layer containing the resin composition; a printed wiring board including an insulating layer formed of a cured product of the resin composition; and a semiconductor device including the printed wiring board.

The present invention will be described below with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and may be modified as desired without departing from the scope of the claims of the present invention and their equivalents.

In this specification, unless otherwise specified, the term "non-volatile components" refers to all non-volatile components in the resin composition excluding the solvent. Unless otherwise specified, the term "resin components" refers to the non-volatile components of the resin composition excluding the inorganic filler (C) described below. The term "liquid resin" refers to a resin that is liquid at a temperature of 20°C.

[Resin composition]
The resin composition of the present invention is a resin composition containing (A) a thermosetting resin and (B) a thermoplastic resin, wherein the content of component (A) is 10 mass% or more when the non-volatile components in the resin composition are taken as 100 mass%, the content of component (B) is 10 mass% or less when the non-volatile components in the resin composition are taken as 100 mass%, the biomass ratio of the resin components in the resin composition is 5 mass% or more, and the biomass ratio of liquid resin in the resin components is 40 mass% or less.

As mentioned above, the inventors have found, as a result of intensive research, that when the biomass ratio of the resin component containing the (A) component and the (B) component is increased, the peel strength is decreased and the insulation reliability is deteriorated. Furthermore, as a result of further intensive research, the inventors have found that when the biomass ratio of the liquid resin in the resin component containing the (A) component and the (B) component is increased, the peel strength is further decreased and the insulation reliability is further deteriorated. In the resin composition of the present invention, the contents of the (A) component and the (B) component are adjusted to be 10% by mass or more and 10% by mass or less, respectively, when the non-volatile components in the resin composition are taken as 100% by mass, and the (A) component and the (B) component are adjusted so that the biomass ratio of the liquid resin in the resin component is 40% by mass or less, which is a low biomass ratio of the liquid resin. This makes it possible to obtain a cured product with high peel strength and excellent insulation reliability even if the biomass ratio of the entire resin component is increased to 5% by mass or more. In addition, even if the biomass ratio of the entire resin component is increased to 5 mass% or more, it is possible to obtain a cured product with high peel strength and excellent insulation reliability, so it is also possible to obtain a cured product with a high biomass ratio in the entire resin composition. Furthermore, it is usually possible to obtain a cured product with excellent lamination properties.

The biomass ratio of the resin component in the resin composition is 5% by mass or more, preferably 5.5% by mass or more, and more preferably 6% by mass or more. There is no particular upper limit, but it can be 100% by mass or less. The biomass ratio can be calculated by the method described in the examples below. Even if the resin composition contains a resin component that has been certified by the mass balance method, the biomass ratio of the resin component in the resin composition is calculated by the method described in the examples below.

The biomass ratio of the liquid resin in the resin component is 40% by mass or less, preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, from the viewpoint of obtaining the effects of the present invention significantly. The lower limit is not particularly limited, but it may be 0% by mass or more. The biomass ratio of the liquid resin in the resin component can be calculated by the method described in the examples below. When the resin component contains multiple liquid resins, the biomass ratio of the liquid resin in the resin component may be within this range. Even when the resin composition contains a liquid resin certified by the mass balance method, the biomass ratio of the liquid resin in the resin component is calculated by the method described in the examples below.

The resin composition may contain (A) a thermosetting resin and (B) a thermoplastic resin in combination with (C) an inorganic filler and (D) other additives. Each component contained in the resin composition is described below.

<(A) Thermosetting resin>
The resin composition of the present invention contains a thermosetting resin (A) as the component (A). The type of the thermosetting resin (A) is not particularly limited as long as it can be thermally cured. The thermosetting resin (A) may be used alone or in combination of two or more types.

As the (A) thermosetting resin, a thermosetting resin used when forming an insulating layer of a printed wiring board can be used. Therefore, one embodiment of the resin composition contains either (A-1) an epoxy resin or (A-2) a curing agent as the (A) thermosetting resin. The (A) thermosetting resin may further contain (A-3) a radical polymerizable resin and (A-4) a curing accelerator, as necessary.

-(A-1) Epoxy resin-
The epoxy resin (A-1) is a thermosetting resin having an epoxy group. The epoxy resin may be an epoxy resin derived from a fossil resource or may be an epoxy resin derived from biomass. The epoxy resin (A-1) may be used alone or in combination of two or more kinds.

Examples of epoxy resins include bixylenol type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, naphthol novolac type epoxy resins, phenol novolac type epoxy resins, tert-butyl-catechol type epoxy resins, naphthalene type epoxy resins, naphthol type epoxy resins, anthracene type epoxy resins, glycidylamine type epoxy resins, glycidyl ester type epoxy resins, cresol novolac type epoxy resins, Examples of epoxy resins include phenol aralkyl epoxy resins, biphenyl epoxy resins, aliphatic epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane epoxy resins, cyclohexane dimethanol epoxy resins, naphthylene ether epoxy resins, trimethylol epoxy resins, tetraphenylethane epoxy resins, isocyanurate epoxy resins, phenolphthalimidine epoxy resins, epoxidized soybean oil, cashew-modified epoxy resins, and epoxidized cardanol resins. Epoxidized soybean oil refers to an epoxy resin in which all or part of the unsaturated bonds of soybean oil have been epoxidized, cashew-modified epoxy resins refers to epoxy resins modified with cashew oil, and epoxidized cardanol resins refers to epoxy resins in which all or part of the cardanol resin has been epoxidized.

The epoxy resin preferably has two or more epoxy groups in one molecule. The proportion of epoxy resin having two or more epoxy groups in one molecule relative to 100% by mass of the non-volatile components of the epoxy resin is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

Epoxy resins include epoxy resins that are liquid at a temperature of 20°C (hereinafter sometimes referred to as "liquid epoxy resins") and epoxy resins that are solid at a temperature of 20°C (hereinafter sometimes referred to as "solid epoxy resins"). The resin composition may contain only liquid epoxy resins as the epoxy resin, or may contain only solid epoxy resins, or may contain a combination of liquid epoxy resins and solid epoxy resins.

The resin composition may contain only epoxy resin derived from fossil resources, or may contain only epoxy resin derived from biomass, or may contain a combination of epoxy resin derived from fossil resources and epoxy resin derived from biomass. Also, the resin composition may contain only solid epoxy resin derived from fossil resources, or may contain a combination of solid epoxy resin derived from fossil resources and liquid epoxy resin derived from biomass.

The liquid epoxy resin is preferably a liquid epoxy resin having two or more epoxy groups in one molecule. In addition, the liquid epoxy resin is preferably a liquid epoxy resin derived from biomass.

Preferred liquid epoxy resins are bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AF type epoxy resins, naphthalene type epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, phenol novolac type epoxy resins, alicyclic epoxy resins having an ester skeleton, cyclohexane type epoxy resins, cyclohexane dimethanol type epoxy resins, epoxy resins having a butadiene structure, aliphatic epoxy resins, epoxidized soybean oil, cashew modified epoxy resins, and epoxidized cardanol resins, with bisphenol A type epoxy resins, aliphatic epoxy resins, epoxidized soybean oil, cashew modified epoxy resins, and epoxidized cardanol resins being more preferable.

Specific examples of liquid epoxy resins derived from fossil resources include DIC's "HP4032", "HP4032D", and "HP4032SS" (naphthalene type epoxy resins); Mitsubishi Chemical's "828US", "828EL", "jER828EL", "825", and "Epicoat 828EL" (bisphenol A type epoxy resins); Mitsubishi Chemical's "jER807" and "1750" (bisphenol F type epoxy resins); Mitsubishi Chemical's "jER152" (phenol novolac type epoxy resin); Mitsubishi Chemical's "630", "630LSD", and "604" (glycidylamine type epoxy resins); ADEKA's "ED-523T" (glycilol type epoxy resin); ADEKA's "EP-3950L" and "EP-3980S" (glycidyl amine type epoxy resin); ADEKA's "EP-4088S" (dicyclopentadiene type epoxy resin); Nippon Steel Chemical & Material's "ZX1059" (mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin); Nagase ChemteX's "EX-721" (glycidyl ester type epoxy resin); Daicel's "Celloxide 2021P" (alicyclic epoxy resin with ester structure); Daicel's "PB-3600", Nippon Soda's "JP-100" and "JP-200" (epoxy resin with butadiene structure (epoxidized polybutadiene resin)); Nippon Steel Chemical & Material's "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin), etc.

Specific examples of liquid epoxy resins derived from biomass include "Denacol EX-521" (aliphatic epoxy resin) manufactured by Nagase ChemteX Corporation, "Sanso Cizer E-2000H" (epoxidized soybean oil) manufactured by New Japan Chemical Co., Ltd., "LITE 514SE" (cashew-modified epoxy resin) manufactured by Cardolite Corporation, and "FE-5130" (epoxidized cardanol resin) manufactured by Tohoku Kako Co., Ltd.

As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in one molecule is preferable, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is more preferable.

As solid epoxy resins, bixylenol type epoxy resins, naphthalene type epoxy resins, naphthalene type tetrafunctional epoxy resins, naphthol novolac type epoxy resins, cresol novolac type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, naphthol type epoxy resins, biphenyl type epoxy resins, naphthylene ether type epoxy resins, anthracene type epoxy resins, bisphenol A type epoxy resins, bisphenol AF type epoxy resins, phenol aralkyl type epoxy resins, tetraphenylethane type epoxy resins, and phenolphthalimidine type epoxy resins are preferred, with biphenyl type epoxy resins and naphthylene ether type epoxy resins being more preferred.

Specific examples of solid epoxy resins derived from fossil resources include DIC's "HP4032H" (naphthalene type epoxy resin); DIC's "HP-4700" and "HP-4710" (naphthalene type tetrafunctional epoxy resins); DIC's "N-690" (cresol novolac type epoxy resin); DIC's "N-695" (cresol novolac type epoxy resin); DIC's "HP-7200", "HP-7200HH", "HP-7200H", and "HP-7200L" (dicyclopentadiene type epoxy resins); DIC's "EXA- 7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (naphthylene ether type epoxy resin); "EPPN-502H" (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC3000H", "NC3000", "NC3000L", "NC3000FH", "NC3100" (biphenyl type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "ESN475V", "ESN4100V" (naphthalene type epoxy resin); "ESN485" (naphthol type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "ESN375" (dihydroxynaphthalene type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YX4000H", "YX4000", "YX4000HK", "YL7890" (bixylenol type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YL6121" (biphenyl type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YX8800" (anthracene type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; Examples include "YX7700" (phenol aralkyl type epoxy resin); "PG-100" and "CG-500" manufactured by Osaka Gas Chemicals; "YX7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical; "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Chemical; "jER1010" (bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical; "jER1031S" (tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical; and "WHR991S" (phenolphthalimidine type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.

When a liquid epoxy resin and a solid epoxy resin are used in combination as the epoxy resin, the mass ratio between them (liquid epoxy resin:solid epoxy resin) is preferably 1:0.01 to 1:20, more preferably 1:0.05 to 1:10, and particularly preferably 1:0.1 to 1:7.

The epoxy equivalent of the epoxy resin is preferably 50 g/eq. to 5,000 g/eq., more preferably 60 g/eq. to 3,000 g/eq., even more preferably 80 g/eq. to 2,000 g/eq., and particularly preferably 110 g/eq. to 1,000 g/eq. The epoxy equivalent represents the mass of the resin per equivalent of epoxy groups. This epoxy equivalent can be measured according to JIS K7236.

The weight average molecular weight (Mw) of the epoxy resin is preferably 100 to 5,000, more preferably 250 to 3,000, and even more preferably 400 to 1,500. The weight average molecular weight of the resin can be measured as a polystyrene-equivalent value by gel permeation chromatography (GPC).

The content of the epoxy resin as component (A-1) is preferably 1% by mass or more, more preferably 5% by mass or more, and particularly preferably 10% by mass or more, and is preferably 45% by mass or less, more preferably 40% by mass or less, and particularly preferably 35% by mass or less, assuming that the non-volatile components in the resin composition are 100% by mass, from the viewpoint of obtaining a cured product that exhibits good mechanical strength and insulation reliability.

In the present invention, the content of each component in the resin composition is the value when the non-volatile components in the resin composition are taken as 100% by mass, unless otherwise specified.

The content of the liquid epoxy resin contained in the (A-1) component is preferably 0% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and preferably 10% by mass or less, more preferably 9% by mass or less, and even more preferably 8% by mass or less, when the non-volatile components in the resin composition are taken as 100% by mass, from the viewpoint of obtaining the effects of the present invention significantly. The content of the biomass-derived liquid epoxy resin contained in the (A-1) component is preferably 0% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and preferably 10% by mass or less, more preferably 9% by mass or less, and even more preferably 8% by mass or less, when the non-volatile components in the resin composition are taken as 100% by mass, from the viewpoint of obtaining the effects of the present invention significantly.

The content of the solid epoxy resin contained in component (A-1) is preferably 1% by mass or more, more preferably 3% by mass or more, and particularly preferably 5% by mass or more, and is preferably 45% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less, assuming that the non-volatile components in the resin composition are 100% by mass, from the viewpoint of obtaining a cured product that exhibits good mechanical strength and insulation reliability.

The biomass ratio of the epoxy resin contained in the resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, from the viewpoint of obtaining a significant effect of the present invention. The biomass ratio can be calculated by the method described in the examples below.

--(A-2) Curing agent--
The (A-2) curing agent is a thermosetting resin having a function of reacting with the (A-1) component to cure the resin composition. The (A-2) curing agent as the (A-2) component does not include those corresponding to the above-mentioned (A-1) component. The curing agent may be a curing agent derived from a fossil resource, or may be a curing agent derived from biomass. The (A-2) curing agent may be used alone or in combination of two or more types.

Examples of the (A-2) curing agent include active ester curing agents, phenolic curing agents, naphthol curing agents, benzoxazine curing agents, cyanate ester curing agents, and carbodiimide curing agents. Among these, from the viewpoint of obtaining the effects of the present invention more significantly, it is preferable that the (A-2) component contains one or more of the active ester curing agents, phenolic curing agents, naphthol curing agents, and benzoxazine curing agents.

(A-2) The curing agent includes a liquid curing agent that is liquid at a temperature of 20°C (hereinafter sometimes referred to as a "liquid curing agent") and a curing agent that is solid at a temperature of 20°C (hereinafter sometimes referred to as a "solid curing agent"). The resin composition may contain only a liquid curing agent as the curing agent, or may contain only a solid curing agent, or may contain a combination of a liquid curing agent and a solid curing agent.

The curing agent may be a fossil resource-derived curing agent or a biomass-derived curing agent, but from the viewpoint of obtaining the effects of the present invention more significantly, it is preferable to include a biomass-derived curing agent, and a combination of a fossil resource-derived curing agent and a biomass-derived curing agent is preferable. In addition, the resin composition may contain a combination of a fossil resource-derived solid curing agent and a biomass-derived solid curing agent as the curing agent, or may contain a combination of a biomass-derived liquid curing agent, a fossil resource-derived solid curing agent, and a biomass-derived solid curing agent.

The active ester-based hardener is preferably a solid hardener, and in particular, a solid hardener derived from biomass.

There are no particular limitations on the active ester curing agent, but generally compounds having two or more highly reactive ester groups in one molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, esters of heterocyclic hydroxy compounds, esters having a furan skeleton with carbonyl groups bonded to the 2nd and 5th positions, and esters having a thiophene skeleton with carbonyl groups bonded to the 2nd and 5th positions, are preferably used. The active ester curing agent is preferably one obtained by a condensation reaction between a carboxylic acid compound and/or a thiocarboxylic acid compound and a hydroxy compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferred, and an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, and furandicarboxylic acid. Examples of the phenol compound or naphthol compound include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenolphthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, hexestrol, daidzein, equol, curcumin, phenol, o-cresol, m-cresol, p-cresol, cardanol, eugenol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, resveratrol, 3,4'-dihydroxyflavone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-phenol polyadducts and other dicyclopentadiene-type diphenol compounds, and phenol novolak. Here, "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing one molecule of dicyclopentadiene with two molecules of phenol.

Specifically, active ester-based curing agents having a furan skeleton with carbonyl groups bonded to the 2nd and 5th positions, active ester-based curing agents having a thiophene skeleton with carbonyl groups bonded to the 2nd and 5th positions, active ester-based curing agents containing a dicyclopentadiene-type diphenol structure, active ester-based curing agents containing a naphthalene structure, active ester-based curing agents containing an acetylated product of phenol novolac, and active ester-based curing agents containing a benzoylated product of phenol novolac are preferred, and among them, active ester-based curing agents having a furan skeleton with carbonyl groups bonded to the 2nd and 5th positions, active ester-based curing agents having a thiophene skeleton with carbonyl groups bonded to the 2nd and 5th positions are more preferred, and active ester-based curing agents having a furan skeleton with carbonyl groups bonded to the 2nd and 5th positions are even more preferred. In addition, it is preferable that the active ester-based curing agents having a furan skeleton with carbonyl groups bonded to the 2nd and 5th positions and the active ester-based curing agents having a thiophene skeleton with carbonyl groups bonded to the 2nd and 5th positions are solid curing agents derived from biomass. "Dicyclopentadiene-type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

The active ester-based curing agent can be obtained, for example, by a condensation reaction of a hydroxyl group-containing aromatic compound having an aromatic hydroxyl group; a dicarboxylic acid halide; and a divalent phenol compound. For example, a biomass-derived active ester-based curing agent can be obtained by using, as the dicarboxylic acid halide, a dicarboxylic acid halide having a furan skeleton or a thiophene skeleton derived from any biomass such as plant-derived glucose, plant-derived cellulose, and plant-derived fructose.

Commercially available active ester curing agents derived from fossil resources include active ester compounds containing a dicyclopentadiene-type diphenol structure such as "EXB-9451", "EXB-9460", "EXB-9460S", "HPC-8000-65T", "HPC-8000H-65TM", and "HPC-8000L-65TM" (manufactured by DIC Corporation), active ester compounds containing a naphthalene structure such as "EXB-9416-70BK", "EXB-8100L-65T", "EXB-8150-65T", "EXB-8150L-65T", "HPC-8150-60T", "HPC-8150-62T", and "HP-B-8151-62T" (manufactured by DIC Corporation), and phenol novo Examples of active ester compounds containing acetylated phenol novolac include "DC808" (manufactured by Mitsubishi Chemical Corporation), active ester compounds containing benzoylated phenol novolac include "YLH1026" (manufactured by Mitsubishi Chemical Corporation), active ester curing agents that are acetylated phenol novolac include "DC808" (manufactured by Mitsubishi Chemical Corporation), active ester curing agents that are benzoylated phenol novolac include "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), and "YLH1048" (manufactured by Mitsubishi Chemical Corporation), and an active ester compound containing a styryl group includes "PC1300-02-65MA" (manufactured by Air Water Corporation).

The phenol-based hardener and naphthol-based hardener are preferably solid hardeners, and the solid hardener may be either a solid hardener derived from fossil resources or a solid hardener derived from biomass.

As the phenol-based hardener and naphthol-based hardener, from the viewpoint of heat resistance and water resistance, a phenol-based hardener having a novolac structure or a naphthol-based hardener having a novolac structure is preferred. Also, from the viewpoint of obtaining the effects of the present invention significantly, a nitrogen-containing phenol-based hardener is preferred, and a triazine skeleton-containing phenol-based hardener is more preferred.

Specific examples of phenol-based hardeners derived from fossil resources and naphthol-based hardeners derived from fossil resources include "MEH-7700", "MEH-7810", and "MEH-7851" manufactured by Meiwa Kasei Co., Ltd., "NHN", "CBN", and "GPH" manufactured by Nippon Kayaku Co., Ltd., "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN-495V", "SN375", and "SN395" manufactured by Nippon Steel Chemical & Material Co., Ltd., and "TD-2090", "LA-7052", "LA-7054", "LA-1356", "LA3018-50P", "EXB-9500", and "KA-1163" manufactured by DIC Corporation.

A specific example of a biomass-derived phenolic hardener is tannic acid manufactured by Sumitomo Pharma Food & Chemical Co., Ltd.

The benzoxazine-based hardener is preferably a liquid hardener, and more preferably a biomass-derived liquid hardener.

Specific examples of benzoxazine-based curing agents include "HFB2006M" manufactured by Showa Polymer Co., Ltd., and "P-d" and "F-a" manufactured by Shikoku Chemical Industry Co., Ltd.

A specific example of a liquid benzoxazine-based hardener derived from biomass is "CR-276" manufactured by Tohoku Kako Co., Ltd.

Examples of cyanate ester curing agents include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanate phenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanate phenyl-1-(methylethylidene))benzene, bis(4-cyanate phenyl)thioether, and bis(4-cyanate phenyl)ether; polyfunctional cyanate resins derived from phenol novolac and cresol novolac; and prepolymers in which these cyanate resins have been partially converted to triazine. Specific examples of cyanate ester-based hardeners include Lonza Japan's "PT30" and "PT60" (phenol novolac-type multifunctional cyanate ester resins), "ULL-950S" (multifunctional cyanate ester resin), "BA230" and "BA230S75" (prepolymers in which part or all of bisphenol A dicyanate has been triazine-converted into a trimer).

A carbodiimide curing agent is a compound that has one or more carbodiimide groups (-N=C=N-) in one molecule, and a carbodiimide curing agent that has two or more carbodiimide groups in one molecule is preferable.

Specific examples of carbodiimide-based curing agents include commercially available carbodiimide-based curing agents such as Carbodilite V-03 (carbodiimide group equivalent: 216, V-05 (carbodiimide group equivalent: 262), V-07 (carbodiimide group equivalent: 200), and V-09 (carbodiimide group equivalent: 200) manufactured by Nisshinbo Chemical Co., Ltd.; and Stavaxol P (carbodiimide group equivalent: 302) manufactured by Rhein Chemie.

The ratio of the amount of the epoxy resin (A-1) to the component (A-2) is preferably in the range of 1:0.01 to 1:5, more preferably 1:0.3 to 1:3, and even more preferably 1:0.5 to 1:2, in terms of the ratio of [total number of epoxy groups in the epoxy resin (A-1)] to [total number of active groups in the component (A-2)]. Here, the "number of epoxy groups in the epoxy resin" refers to the total value obtained by dividing the mass of the non-volatile components of the epoxy resin present in the resin composition by the epoxy equivalent. The "number of active groups in the component (A-2)" refers to the total value obtained by dividing the mass of the non-volatile components of the component (A-2) present in the resin composition by the active group equivalent. By setting the ratio of the amount of the epoxy resin to the component (A-2) within this range, the effects of the present invention can be obtained significantly.

From the viewpoint of significantly obtaining the desired effect of the present invention, the content of the (A-2) component is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, assuming that the non-volatile components in the resin composition layer are 100% by mass. The upper limit is preferably 35% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less, and even more preferably 10% by mass or less.

In order to obtain the desired effect of the present invention significantly, the content of the liquid hardener is preferably 1% by mass or more, more preferably 1.5% by mass or more, and more preferably 3% by mass or more, when the non-volatile components in the resin composition layer are taken as 100% by mass. The upper limit is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. In order to obtain the desired effect of the present invention significantly, the content of the biomass-derived liquid hardener contained in the (A-2) component is preferably 1% by mass or more, more preferably 1.5% by mass or more, and even more preferably 3% by mass or more, when the non-volatile components in the resin composition are taken as 100% by mass. The upper limit is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

In order to obtain the desired effect of the present invention significantly, the content of the solid hardener is preferably 1% by mass or more, more preferably 2% by mass or more, and more preferably 3% by mass or more, when the non-volatile components in the resin composition layer are taken as 100% by mass. The upper limit is preferably 25% by mass or less, more preferably 23% by mass or less, even more preferably 20% by mass or less, and 10% by mass or less. In order to obtain the desired effect of the present invention significantly, the content of the biomass-derived solid hardener contained in the (A-2) component is preferably 1% by mass or more, more preferably 1.5% by mass or more, and more preferably 3% by mass or more, when the non-volatile components in the resin composition are taken as 100% by mass. The upper limit is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

--(A-3) Radical Polymerizable Resin--
The (A-3) radical polymerizable resin is a thermosetting resin that contains a radical polymerizable unsaturated group, and when the resin composition is heated, the (A-3) radical polymerizable resin reacts with thermal radicals generated by the heating to obtain a cured product. The (A-3) radical polymerizable resin as the (A-3) component does not include those that correspond to the above-mentioned (A-1) and (A-2) components. The (A-3) radical polymerizable resin may be used alone or in combination of two or more types.

The resin composition may contain, as the radical polymerizable resin, a radical polymerizable resin derived from a fossil resource or a radical polymerizable resin derived from biomass, but from the viewpoint of obtaining the effects of the present invention more significantly, it is preferable that the resin composition contains only a radical polymerizable resin derived from biomass.

The type of radical polymerizable resin is not particularly limited as long as it has one or more (preferably two or more) radical polymerizable unsaturated groups in one molecule. Examples of the radical polymerizable resin include resins having one or more radical polymerizable unsaturated groups selected from maleimide groups, vinyl groups, allyl groups, styryl groups, vinylphenyl groups, acryloyl groups, methacryloyl groups, fumaroyl groups, maleoyl groups, and propenyl groups. Among these, from the viewpoint of obtaining the effects of the present invention significantly, the radical polymerizable resin is preferably one or more selected from maleimide resins, (meth)acrylic resins, allyl resins, and styryl resins, and more preferably either (meth)acrylic resins or allyl resins.

Radically polymerizable resins include liquid radically polymerizable resins that are liquid at a temperature of 20°C (hereinafter sometimes referred to as "liquid radically polymerizable resins") and radically polymerizable resins that are solid at a temperature of 20°C (hereinafter sometimes referred to as "solid radically polymerizable resins"). The resin composition may contain only liquid radically polymerizable resins as the radically polymerizable resins, or may contain only solid radically polymerizable resins, or may contain a combination of liquid radically polymerizable resins and solid radically polymerizable resins, but from the viewpoint of obtaining the effects of the present invention more significantly, it is preferable to contain only liquid radically polymerizable resins.

The type of (meth)acrylic resin is not particularly limited, and may be a monomer or oligomer, so long as it has one or more (preferably two or more) (meth)acryloyl groups in one molecule. Here, the term "(meth)acryloyl group" is a general term for acryloyl groups and methacryloyl groups.

Examples of (meth)acrylic resins derived from fossil resources include (meth)acrylate monomers, as well as (meth)acrylic resins such as "A-DOG" (manufactured by Shin-Nakamura Chemical Co., Ltd.), "DCP-A" (manufactured by Kyoeisha Chemical Co., Ltd.), "NPDGA", "FM-400", "R-687", "THE-330", "PET-30", and "DPHA" (all manufactured by Nippon Kayaku Co., Ltd.). . "(Meth)acrylate" is a term that includes methacrylate and acrylate, as well as combinations thereof.

An example of a biomass-derived (meth)acrylic resin is ARONIX M-930 (manufactured by Toagosei Co., Ltd.).

The type of allyl resin is not particularly limited as long as it has one or more allyl groups in one molecule, and it may be a monomer or an oligomer. Examples of allyl resins derived from biomass include β-carotene.

There is no particular limitation on the type of maleimide resin, so long as it has one or more (preferably two or more) maleimide groups (2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl groups) in one molecule. Examples of maleimide resins include (1) maleimide resins containing an aliphatic skeleton (preferably an aliphatic skeleton having 36 carbon atoms derived from dimer diamine), such as "BMI-3000J", "BMI-5000", "BMI-1400", "BMI-1500", "BMI-1700", and "BMI-689" (all manufactured by DigiCner Molecules), and "SLK6895-T90" (manufactured by Shin-Etsu Chemical Co., Ltd.); (2) maleimide resins containing an indane skeleton, as described in the Japan Institute of Invention and Innovation Disclosure Technical Bulletin No. 2020-500211; and (3) maleimide resins containing an aromatic ring skeleton directly bonded to the nitrogen atom of the maleimide group, such as "MIR-3000-70MT" (manufactured by Nippon Kayaku Co., Ltd.), "BMI-4000" (manufactured by Daiwa Kasei Co., Ltd.), and "BMI-80" (manufactured by Keiai Kasei Co., Ltd.).

The type of styryl resin is not particularly limited, and may be a monomer or oligomer, as long as it has one or more (preferably two or more) styryl groups or vinylphenyl groups in one molecule. Examples of styryl resins include styrene monomers, as well as styryl resins such as "OPE-2St", "OPE-2St 1200", and "OPE-2St 2200" (all manufactured by Mitsubishi Gas Chemical Co., Ltd.).

From the viewpoint of obtaining a significant effect of the present invention, the content of the radical polymerizable resin is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less, when the non-volatile components in the resin composition are taken as 100% by mass.

In order to obtain the effects of the present invention remarkably, the content of the liquid radical polymerizable resin is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3.5% by mass or less, when the non-volatile components in the resin composition are taken as 100% by mass, from the viewpoint of obtaining the effects of the present invention remarkably. In order to obtain the effects of the present invention remarkably, the content of the liquid radical polymerizable resin derived from biomass contained in the thermosetting resin is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, and preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3.5% by mass or less, when the non-volatile components in the resin composition are taken as 100% by mass.

--(A-4) Curing Accelerator--
The (A-4) curing accelerator is a thermosetting resin that functions as a curing catalyst to accelerate the curing of the (A-1) epoxy resin. The (A-4) curing accelerator may be a curing accelerator derived from fossil resources, or may be a curing accelerator derived from biomass. The (A-4) curing accelerator as the (A-4) component does not include those that fall under the above-mentioned (A-1) to (A-3) components.

As the (A-4) curing accelerator, a compound that accelerates the curing of the epoxy resin can be used. Examples of such (A-4) curing accelerators include phosphorus-based curing accelerators, urea-based curing accelerators, guanidine-based curing accelerators, imidazole-based curing accelerators, metal-based curing accelerators, and amine-based curing accelerators. As the (A-4) curing accelerator, one type may be used alone, or two or more types may be used in combination.

Examples of phosphorus-based curing accelerators include aliphatic phosphonium salts such as tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium acetate, tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, bis(tetrabutylphosphonium)pyromellitate, tetrabutylphosphonium hydrogenhexahydrophthalate, tetrabutylphosphonium 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenolate, and di-tert-butyldimethylphosphonium tetraphenylborate; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, propyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, and tetraphenyl Aromatic phosphonium salts such as phosphonium bromide, p-tolyltriphenylphosphonium tetra-p-tolylborate, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra-p-tolylborate, triphenylethylphosphonium tetraphenylborate, tris(3-methylphenyl)ethylphosphonium tetraphenylborate, tris(2-methoxyphenyl)ethylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate; aromatic phosphine-borane complexes such as triphenylphosphine-triphenylborane; aromatic phosphine-quinone addition products such as triphenylphosphine-p-benzoquinone addition products; tributylphosphine, tri- Aliphatic phosphines such as tert-butylphosphine, trioctylphosphine, di-tert-butyl(2-butenyl)phosphine, di-tert-butyl(3-methyl-2-butenyl)phosphine, and tricyclohexylphosphine; dibutylphenylphosphine, di-tert-butylphenylphosphine, methyldiphenylphosphine, ethyldiphenylphosphine, butyldiphenylphosphine, diphenylcyclohexylphosphine, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-isopropylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-tert-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,5-dimethylphenyl)phosphine, tris(2,6-dimethylphenyl)phosphine, tris(3,5-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, tris(4-tert-butoxyphenyl)phosphine, diphenyl-2-pyridylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,2-bis(diphenylphosphino)acetylene, 2,2'-bis(diphenylphosphino)diphenyl ether and other aromatic phosphines.

Examples of urea-based hardening accelerators include 1,1-dimethylurea; aliphatic dimethylureas such as 1,1,3-trimethylurea, 3-ethyl-1,1-dimethylurea, 3-cyclohexyl-1,1-dimethylurea, and 3-cyclooctyl-1,1-dimethylurea; 3-phenyl-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(2-methylphenyl)-1,1-dimethylurea, 3-(4-methylphenyl)-1,1-dimethylurea, and 3-(3,4-dimethylphenyl)-1,1-dimethylurea. Examples of aromatic dimethylureas include toluene bis(dimethylurea), 3-(4-isopropylphenyl)-1,1-dimethylurea, 3-(4-methoxyphenyl)-1,1-dimethylurea, 3-(4-nitrophenyl)-1,1-dimethylurea, 3-[4-(4-methoxyphenoxy)phenyl]-1,1-dimethylurea, 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea, 3-[3-(trifluoromethyl)phenyl]-1,1-dimethylurea, N,N-(1,4-phenylene)bis(N',N'-dimethylurea), and N,N-(4-methyl-1,3-phenylene)bis(N',N'-dimethylurea) [toluene bisdimethylurea].

Examples of guanidine-based curing accelerators include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide.

Examples of imidazole-based curing accelerators include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2- Phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl -(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct imidazole compounds such as 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, as well as adducts of imidazole compounds and epoxy resins. Commercially available imidazole curing accelerators include, for example, "1B2PZ", "2E4MZ", "2MZA-PW", "2MZ-OK", "2MA-OK", "2MA-OK-PW", "2PHZ", "2PHZ-PW", "Cl1Z", "Cl1Z-CN", "Cl1Z-CNS", and "C11Z-A" manufactured by Shikoku Chemical Industry Co., Ltd.; and "P200-H50" manufactured by Mitsubishi Chemical Corporation.

Metal-based curing accelerators include, for example, organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organocobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organocopper complexes such as copper (II) acetylacetonate, organozinc complexes such as zinc (II) acetylacetonate, organoiron complexes such as iron (III) acetylacetonate, organonickel complexes such as nickel (II) acetylacetonate, and organomanganese complexes such as manganese (II) acetylacetonate. Organometallic salts include, for example, zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

Examples of amine-based curing accelerators include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene. Commercially available amine-based curing accelerators may be used, such as "MY-25" manufactured by Ajinomoto Fine-Techno Co., Ltd.

From the viewpoint of obtaining a significant effect of the present invention, the content of the curing accelerator (A-4) is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and even more preferably 0.03% by mass or more, and is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.1% by mass or less, based on 100% by mass of the non-volatile components in the resin composition.

The content of (A) thermosetting resin is 10% by mass or more, preferably 15% by mass or more, and more preferably 20% by mass or more, based on 100% by mass of non-volatile components in the resin composition, from the viewpoint of obtaining a significant effect of the present invention. The upper limit is preferably 70% by mass or less, more preferably 60% by mass or less, and even more preferably 50% by mass or less, 40% by mass or less, or 30% by mass or less.

From the viewpoint of obtaining the remarkable effects of the present invention, all liquid resins contained as the (A) thermosetting resin are preferably at least one of (A-1) epoxy resin, (A-2) curing agent, and (A-3) radical polymerizable resin, and more preferably at least one of (A-1) epoxy resin and (A-2) curing agent.

The content of all liquid resins in (A) thermosetting resin is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of non-volatile components in the resin composition, from the viewpoint of obtaining a significant effect of the present invention, and is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more.

(A) The biomass ratio of the entire thermosetting resin is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, from the viewpoint of obtaining a significant effect of the present invention. The biomass ratio can be calculated by the method described in the examples below.

<(B) Thermoplastic resin>
The resin composition of the present invention contains a thermoplastic resin (B) as the component (B). The thermoplastic resin (B) as the component (B) does not include those corresponding to the above-mentioned component (A). The thermoplastic resin (B) may be used alone or in combination of two or more kinds.

(B) Thermoplastic resins include thermoplastic resins that are liquid at a temperature of 20°C (hereinafter sometimes referred to as "liquid thermoplastic resins") and thermoplastic resins that are solid at a temperature of 20°C (hereinafter sometimes referred to as "solid thermoplastic resins"). The resin composition may contain only liquid thermoplastic resins as thermoplastic resins, or may contain only solid thermoplastic resins, or may contain a combination of liquid thermoplastic resins and solid thermoplastic resins, but from the viewpoint of obtaining the effects of the present invention more significantly, it is preferable that the resin composition contains only solid thermoplastic resins.

The resin composition may contain, as the thermoplastic resin (B), a thermoplastic resin derived from a fossil resource, or may contain a thermoplastic resin derived from a biomass. In addition, the resin composition may contain, as the thermoplastic resin (B), only a solid thermoplastic resin derived from a fossil resource, only a solid thermoplastic resin derived from a biomass, or may contain a combination of a solid thermoplastic resin derived from a fossil resource and a solid thermoplastic resin derived from a biomass.

The resin composition may contain, as the thermoplastic resin (B), a particulate thermoplastic resin that maintains a particulate form in the resin composition, or may contain a non-particulate thermoplastic resin that is mixed or dissolved in the resin composition. Of these, it is preferable for the resin composition to contain a non-particulate thermoplastic resin, from the viewpoint of obtaining the effects of the present invention more significantly.

Examples of non-particulate thermoplastic resins include polyimide resins, phenoxy resins, polyvinyl acetal resins, polyolefin resins, polybutadiene resins, polyamideimide resins, polyetherimide resins, polysulfone resins, polyethersulfone resins, polyphenylene ether resins, polycarbonate resins, polyetheretherketone resins, polyester resins, and polyamide resins. In one embodiment, the (B) thermoplastic resin preferably contains a thermoplastic resin selected from the group consisting of polyimide resins and phenoxy resins, and more preferably contains a phenoxy resin. In addition, the thermoplastic resin may be used alone or in combination of two or more types.

Specific examples of polyimide resins include "SLK-6100" manufactured by Shin-Etsu Chemical Co., Ltd., and "Rikacoat SN20" and "Rikacoat PN20" manufactured by New Japan Chemical Co., Ltd.

Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenolacetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene skeleton, and trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group.

Specific examples of phenoxy resins include Mitsubishi Chemical's "1256" and "4250" (both phenoxy resins containing a bisphenol A skeleton); Mitsubishi Chemical's "YX8100" (phenoxy resin containing a bisphenol S skeleton); Mitsubishi Chemical's "YX6954" (phenoxy resin containing a bisphenol acetophenone skeleton); Nippon Steel Chemical & Material's "FX280" and "FX293"; Mitsubishi Chemical's "YL7500BH30", "YX6954BH30", "YX7553", "YX7553BH30", "YL7769BH30", "YL6794", "YL7213", "YL7290", "YL7482", and "YL7891BH30".

Examples of polyvinyl acetal resins include polyvinyl formal resins and polyvinyl butyral resins, with polyvinyl butyral resins being preferred. Specific examples of polyvinyl acetal resins include Denka Butyral 4000-2, Denka Butyral 5000-A, Denka Butyral 6000-C, and Denka Butyral 6000-EP manufactured by Denka Co., Ltd.; and S-LEC BH series, BX series (e.g. BX-5Z), KS series (e.g. KS-1), BL series, and BM series manufactured by Sekisui Chemical Co., Ltd.

Examples of polyolefin resins include ethylene-based copolymer resins such as low-density polyethylene, very low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer; polyolefin-based polymers such as polypropylene and ethylene-propylene block copolymer.

Examples of polybutadiene resins include hydrogenated polybutadiene skeleton-containing resins, hydroxyl group-containing polybutadiene resins, phenolic hydroxyl group-containing polybutadiene resins, carboxyl group-containing polybutadiene resins, acid anhydride group-containing polybutadiene resins, epoxy group-containing polybutadiene resins, isocyanate group-containing polybutadiene resins, urethane group-containing polybutadiene resins, polyphenylene ether-polybutadiene resins, etc.

Specific examples of polyamide-imide resins include "Viromax HR11NN" and "Viromax HR16NN" manufactured by Toyobo Co., Ltd. Specific examples of polyamide-imide resins include modified polyamide-imides such as "KS9100" and "KS9300" (polyamide-imide containing a polysiloxane skeleton) manufactured by Hitachi Chemical Co., Ltd.

An example of a polyethersulfone resin is "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

Specific examples of polysulfone resins include polysulfones "P1700" and "P3500" manufactured by Solvay Advanced Polymers.

A specific example of a polyphenylene ether resin is NORYL SA90 manufactured by SABIC. A specific example of a polyetherimide resin is ULTEM manufactured by GE.

Examples of polycarbonate resins include hydroxyl group-containing carbonate resins, phenolic hydroxyl group-containing carbonate resins, carboxyl group-containing carbonate resins, acid anhydride group-containing carbonate resins, isocyanate group-containing carbonate resins, and urethane group-containing carbonate resins. Specific examples of polycarbonate resins include "FPC0220" manufactured by Mitsubishi Gas Chemical Co., Ltd., "T6002" and "T6001" (polycarbonate diols) manufactured by Asahi Kasei Chemicals Corporation, and "C-1090", "C-2090", and "C-3090" (polycarbonate diols) manufactured by Kuraray Co., Ltd. Specific examples of polyether ether ketone resins include "Sumiploy K" manufactured by Sumitomo Chemical Co., Ltd.

Examples of polyester resins include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene terephthalate resin, polybutylene naphthalate resin, polytrimethylene terephthalate resin, polytrimethylene naphthalate resin, and polycyclohexane dimethyl terephthalate resin.

Examples of polyamide resins include nylon 6 and nylon 66. The polyamide resin is preferably a biomass-derived polyamide resin. An example of a biomass-derived polyamide resin is "Vegichem Green V335" manufactured by Tsuno Foods Co., Ltd.

Examples of particulate thermoplastic resins include rubber particles, polyamide microparticles, silicone particles, etc., with rubber particles being preferred.

As rubber particles, commercially available products may be used, such as "EXL2655" manufactured by Dow Chemical Japan, and "AC3401N" and "AC3816N" manufactured by Aica Kogyo Co., Ltd.

The weight average molecular weight (Mw) of the (B) thermoplastic resin is preferably 5,000 or more, more preferably 8,000 or more, even more preferably 10,000 or more, and particularly preferably 20,000 or more, from the viewpoint of obtaining a significant effect of the present invention, and is preferably 100,000 or less, more preferably 70,000 or less, even more preferably 60,000 or less, and particularly preferably 50,000 or less.

As another embodiment of the thermoplastic resin (B), the thermoplastic resin (B) may be an elastomer. The thermoplastic elastomer is a resin having flexibility, and is preferably a resin having rubber elasticity or a resin that exhibits rubber elasticity by polymerizing with other components. One type of elastomer may be used alone, or two or more types may be used in combination.

An example of a resin with rubber elasticity is a resin that exhibits an elastic modulus of 1 GPa or less when a tensile test is performed at a temperature of 25°C and a humidity of 40% RH in accordance with the Japanese Industrial Standards (JIS K7161).

The elastomer may be an elastomer derived from fossil resources or may be an elastomer derived from biomass.

The elastomer preferably has a high molecular weight. The number average molecular weight (Mn) of the elastomer is preferably 1,000 or more, more preferably 1,500 or more, even more preferably 2,000 or more, even more preferably 3,000 or more, and particularly preferably 5,000 or more. The upper limit is preferably 1,000,000 or less, more preferably 900,000 or less. The number average molecular weight (Mn) is the number average molecular weight in terms of polystyrene measured using GPC (gel permeation chromatography).

The elastomer is preferably one or more selected from resins having a glass transition temperature (Tg) of 25°C or less and resins that are liquid at 25°C or less. The glass transition temperature of resins having a glass transition temperature (Tg) of 25°C or less is preferably 20°C or less, more preferably 15°C or less. The lower limit of the glass transition temperature is not particularly limited, but it can usually be -15°C or more. Furthermore, resins that are liquid at 25°C are preferably resins that are liquid at 20°C or less, more preferably resins that are liquid at 15°C or less. The glass transition temperature can be measured by DSC (differential scanning calorimetry) at a heating rate of 5°C/min.

As the elastomer, a resin having one or more structures selected from a polybutadiene structure, a polysiloxane structure, a poly(meth)acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, a polycarbonate structure, and a polystyrene structure in the molecule is preferable. Among them, a resin having one or more structures selected from a polybutadiene structure, a poly(meth)acrylate structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, a polycarbonate structure, and a polystyrene structure is more preferable. Furthermore, a resin having one or more structures selected from a polybutadiene structure and a polyalkyleneoxy structure is even more preferable, and a resin having a polybutadiene structure is particularly preferable. "(Meth)acrylate" is a term that includes methacrylate and acrylate, and a combination thereof. These structures may be included in the main chain or in the side chain.

The elastomer may have a functional group capable of reacting with the epoxy resin (A-1). When the elastomer reacts with the epoxy resin (A-1), the mechanical strength of the cured product of the resin composition can be increased. The functional group capable of reacting with the epoxy resin (A-1) includes a functional group that appears upon heating. The functional group capable of reacting with the epoxy resin (A-1) is, for example, one or more functional groups selected from the group consisting of a hydroxy group, a carboxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, a urethane group, and a maleimide group. Among these, the functional group is preferably a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, a urethane group, or a maleimide group, more preferably a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, or a maleimide group, and particularly preferably a phenolic hydroxyl group or a maleimide group. However, the functional group is included. The number average molecular weight (Mn) of the elastomer is preferably 3,000 or more.

An example of an elastomer is a resin containing a polybutadiene structure. The polybutadiene structure may be contained in the main chain or in a side chain. The polybutadiene structure may be partially or completely hydrogenated. A resin containing a polybutadiene structure is sometimes called a "polybutadiene resin." Specific examples of polybutadiene resins include "Ricon 130MA8", "Ricon 130MA13", "Ricon 130MA20", "Ricon 131MA5", "Ricon 131MA10", "Ricon 131MA17", "Ricon 131MA20", and "Ricon 184MA6" (polybutadiene containing an acid anhydride group) manufactured by Cray Valley Corporation; "GQ-1000" (polybutadiene having hydroxyl and carboxyl groups introduced therein), "G-1000", "G-2000", and "G-3000" (polybutadiene having hydroxyl groups at both ends), "GI-1000", "GI-2000", and "GI-3000" (polybutadiene having hydrogenated hydroxyl groups at both ends) manufactured by Nippon Soda Co., Ltd.; and "FCA-061L" (hydrogenated polybutadiene skeleton epoxy resin) manufactured by Nagase ChemteX Corporation. Specific examples of polybutadiene resins include hydroxyl-terminated polybutadiene, linear polyimides made from diisocyanate compounds and tetrabasic acid anhydrides (polyimides described in JP 2006-37083 A and WO 2008/153208 A), and phenolic hydroxyl group-containing butadienes. The content of the butadiene structure in the polyimide resin is preferably 60% by mass to 95% by mass, more preferably 75% by mass to 85% by mass. For details of the polyimide resin, see JP 2006-37083 A and WO 2008/153208 A, the contents of which are incorporated herein by reference.

Another example of an elastomer is a resin containing a poly(meth)acrylate structure. A resin containing a poly(meth)acrylate structure is sometimes called a "poly(meth)acrylic resin." Examples of poly(meth)acrylic resins include Teisan Resin manufactured by Nagase ChemteX Corporation, ME-2000, W-116.3, W-197C, KG-25, and KG-3000 manufactured by Negami Chemical Industries, and ARUFON UH-2000 manufactured by Toagosei Co., Ltd.

Another example of an elastomer is a resin containing a polycarbonate structure. A resin containing a polycarbonate structure is sometimes called a "polycarbonate resin." Examples of polycarbonate resins include "FPC0220" and "FPC2136" manufactured by Mitsubishi Gas Chemical Co., Ltd., "T6002" and "T6001" (polycarbonate diols) manufactured by Asahi Kasei Chemicals Corporation, and "C-1090", "C-2090", and "C-3090" (polycarbonate diols) manufactured by Kuraray Co., Ltd. In addition, linear polyimides made from hydroxyl-terminated polycarbonate, diisocyanate compounds, and tetrabasic acid anhydrides may be used. The content of the carbonate structure in the polyimide resin is preferably 60% to 95% by mass, more preferably 75% to 85% by mass. For details of the polyimide resin, please refer to the description in International Publication No. 2016/129541, the contents of which are incorporated herein by reference.

Another example of an elastomer is a resin containing a polysiloxane structure. A resin containing a polysiloxane structure is sometimes called a "siloxane resin." Examples of siloxane resins include "SMP-2006," "SMP-2003PGMEA," and "SMP-5005PGMEA" manufactured by Shin-Etsu Silicones Co., Ltd., and linear polyimides made from amine-terminated polysiloxane and tetrabasic acid anhydride (see, for example, International Publication No. 2010/053185, JP 2002-12667 A, and JP 2000-319386 A).

Another example of an elastomer is a resin containing a polyalkylene structure or a polyalkyleneoxy structure. A resin containing a polyalkylene structure is sometimes called an "alkylene resin", and a resin containing a polyalkyleneoxy structure is sometimes called an "alkyleneoxy resin". The number of carbon atoms in the polyalkylene structure and the polyalkyleneoxy structure is preferably 2 to 15, more preferably 3 to 10, and even more preferably 5 to 8. Specific examples of alkylene resins and alkyleneoxy resins include "PTXG-1000" and "PTXG-1800" manufactured by Asahi Kasei Fibers Corporation, and "BMI-3000" manufactured by Designer Molecules, Inc.

Another example of an elastomer is a resin containing a polyisoprene structure. A resin containing a polyisoprene structure is sometimes called an "isoprene resin." Specific examples of isoprene resin include "KL-610" and "KL613" manufactured by Kuraray Co., Ltd.

Yet another example of an elastomer is a resin containing a polyisobutylene structure. A resin containing a polyisobutylene structure is sometimes called an "isobutylene resin." Specific examples of isobutylene resins include Kaneka's "SIBSTAR-073T" (styrene-isobutylene-styrene triblock copolymer) and "SIBSTAR-042D" (styrene-isobutylene diblock copolymer).

Another example of an elastomer is a resin containing a polystyrene structure. A resin containing a polystyrene structure is sometimes called a "styrene resin." The styrene resin may be a copolymer containing any repeating unit other than the styrene unit in combination with the styrene unit, or may be a hydrogenated polystyrene resin. Examples of styrene resins include styrene-butadiene-styrene block copolymers (SBS), styrene-isoprene-styrene block copolymers (SIS), styrene-ethylene-butylene-styrene block copolymers (SEBS), styrene-ethylene-propylene-styrene block copolymers (SEPS), styrene-ethylene-ethylene-propylene-styrene block copolymers (SEEPS), styrene-butadiene-butylene-styrene block copolymers (SBBS), styrene-butadiene diblock copolymers, hydrogenated styrene-butadiene block copolymers, hydrogenated styrene-isoprene block copolymers, hydrogenated styrene-butadiene random copolymers, and styrene-maleic anhydride copolymers. Specific examples of styrene resins include hydrogenated styrene-based thermoplastic elastomers "H1041", "Tuftec H1043", "Tuftec P2000", and "Tuftec MP10" (manufactured by Asahi Kasei Corporation); epoxidized styrene-butadiene thermoplastic elastomers "Epofriend AT501" and "CT310" (manufactured by Daicel Corporation); modified styrene-based elastomers having hydroxyl groups "Septon HG252" (manufactured by Kuraray Co., Ltd.); modified styrene-based elastomers having carboxyl groups "Tuftec N503M", modified styrene-based elastomers having amino groups "Tuftec N501", modified styrene-based elastomers having acid anhydride groups "Tuftec M1913" (manufactured by Asahi Kasei Chemicals Corporation); unmodified styrene-based elastomers "Septon S8104" (manufactured by Kuraray Co., Ltd.); styrene-ethylene/butylene-styrene block copolymers "FG1924" (manufactured by Kraton Corporation), "EF-40" (CRAY (manufactured by VALLEY Co., Ltd.)

From the viewpoint of obtaining a significant effect of the present invention, the content of the elastomer is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, relative to 100% by mass of non-volatile components in the resin composition, and is preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less.

The content of (B) thermoplastic resin is 10% by mass or less, preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less, when the non-volatile components in the resin composition are taken as 100% by mass, from the viewpoint of significantly obtaining the desired effect of the present invention. The lower limit is preferably 0% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more.

<(C) Inorganic filler>
The resin composition may further contain an inorganic filler (C) as an optional component in addition to the above-mentioned components (A) and (B).

(C) An inorganic compound is used as the material for the inorganic filler. (C) Examples of the material for the inorganic filler include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silica is particularly suitable. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. In addition, spherical silica is preferable as the silica. (C) The inorganic filler may be used alone or in any combination of two or more kinds in any ratio.

(C) Commercially available inorganic fillers include, for example, "SP60-05" and "SP507-05" manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YC100C", "YA050C", "YA050C-MJE", "YA010C", "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" manufactured by Admatechs Co., Ltd.; "UFP-30", "DAW-03", and "FB-105FD" manufactured by Denka Co., Ltd.; "Silfil NSS-3N", "Silfil NSS-4N", and "Silfil NSS-5N" manufactured by Tokuyama Corporation; "Cellfiers" and "MGH-005" manufactured by Taiheiyo Cement Corporation; and "Sferique" and "BA-1" manufactured by JGC Catalysts and Chemicals Co., Ltd.

(C) The inorganic filler may be a biomass-derived inorganic filler. It is preferable that the biomass-derived inorganic filler is produced from a plant raw material. For example, plants of the Equisetaceae and Poaceae families have the property of absorbing and accumulating silicon components from the ground. Therefore, by burning these plants, silica can be produced as combustion ash (Patent Publication No. 6389349). The biomass-derived inorganic filler may be a commercially available product. An example of a commercially available biomass-derived inorganic filler is "Ethical Silica" manufactured by MIT, which is a biomass silica produced from rice husks.

(C) The average particle size of the inorganic filler is not particularly limited, but is preferably 10 μm or less, more preferably 5 μm or less, even more preferably 3 μm or less, even more preferably 2 μm or less, and particularly preferably 1.5 μm or less. (C) The lower limit of the average particle size of the inorganic filler is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.05 μm or more, even more preferably 0.1 μm or more, and particularly preferably 0.2 μm or more. (C) The average particle size of the inorganic filler can be measured by a laser diffraction/scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic filler is created on a volume basis using a laser diffraction/scattering particle size distribution measuring device, and the median diameter is used as the average particle size. The measurement sample can be prepared by weighing 100 mg of the inorganic filler and 10 g of methyl ethyl ketone into a vial and dispersing it by ultrasonic waves for 10 minutes. The measurement sample was measured using a laser diffraction type particle size distribution measuring device with blue and red light source wavelengths and a flow cell method to measure the volumetric particle size distribution of the inorganic filler, and the average particle size was calculated as the median diameter from the obtained particle size distribution. An example of a laser diffraction type particle size distribution measuring device is the "LA-960" manufactured by Horiba, Ltd.

The specific surface area of the inorganic filler (C) is not particularly limited, but is preferably 0.1 m ² /g or more, more preferably 0.5 m ² /g or more, even more preferably 1 m ² /g or more, and particularly preferably 3 m ² /g or more. The upper limit of the specific surface area of the inorganic filler (C) is not particularly limited, but is preferably 100 m ² /g or less, more preferably 70 m ² /g or less, even more preferably 50 m ² /g or less, even more preferably 30 m ² /g or less, and particularly preferably 10 m ² /g or less. The specific surface area of the inorganic filler is obtained by adsorbing nitrogen gas to the sample surface using a specific surface area measuring device (Macsorb HM-1210 manufactured by Mountech Co., Ltd.) according to the BET method, and calculating the specific surface area using the BET multipoint method.

(C) From the viewpoint of improving moisture resistance and dispersibility, it is preferable that the inorganic filler is treated with a surface treatment agent. Examples of the surface treatment agent include a fluorine-containing silane coupling agent, an aminosilane coupling agent, an epoxysilane coupling agent, a mercaptosilane coupling agent, a silane coupling agent, an alkoxysilane, an organosilazane compound, and a titanate coupling agent. In addition, the surface treatment agent may be used alone or in any combination of two or more types.

Examples of commercially available surface treatment agents include Shin-Etsu Chemical's "KBM403" (3-glycidoxypropyltrimethoxysilane), Shin-Etsu Chemical's "KBM803" (3-mercaptopropyltrimethoxysilane), Shin-Etsu Chemical's "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical's "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical's "SZ-31" (hexamethyldisilazane), Shin-Etsu Chemical's "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical's "KBM-4803" (long-chain epoxy-type silane coupling agent), and Shin-Etsu Chemical's "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane).

From the viewpoint of improving the dispersibility of the inorganic filler, it is preferable that the degree of surface treatment with the surface treatment agent falls within a specified range. Specifically, it is preferable that 100% by mass of the inorganic filler is surface-treated with 0.2% to 5% by mass of the surface treatment agent, more preferably 0.2% to 3% by mass, and even more preferably 0.3% to 2% by mass.

The degree of surface treatment by the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg/m ² or more, more preferably 0.1 mg/m ² or more, and even more preferably 0.2 mg/m ² or more. On the other hand, from the viewpoint of preventing an increase in the melt viscosity of the resin composition or the melt viscosity in the sheet form, it is preferably 1.0 mg/m ² or less, more preferably 0.8 mg/m ² or less, and even more preferably 0.5 mg/m ² or less.

(C) The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (e.g., methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler that has been surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solids, the amount of carbon per unit surface area of the inorganic filler can be measured using a carbon analyzer. An example of a carbon analyzer that can be used is the "EMIA-320V" manufactured by Horiba, Ltd.

From the viewpoint of obtaining a significant effect of the present invention, the content of (C) inorganic filler is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more, and is preferably 85% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less, assuming that the non-volatile components in the resin composition are 100% by mass.

<(D) Other Additives>
The resin composition may further contain other additives as optional components in addition to the above-mentioned components. Examples of such additives include thickeners, defoamers, leveling agents, adhesion promoters, flame retardants, etc. These may be used alone or in combination of two or more in any ratio.

The liquid resin in the resin components is preferably contained in the components (A) and (B). From the viewpoint of obtaining the effects of the present invention more significantly, the liquid resin is preferably contained in the thermosetting resin (A), more preferably in any of the epoxy resin (A-1), the curing agent (A-2), and the radical polymerizable resin (A-3), and even more preferably in any of the epoxy resin (A-1) and the curing agent (A-2).

The total content of the liquid resin in the resin composition is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of non-volatile components in the resin composition, from the viewpoint of obtaining the effects of the present invention significantly, and is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more. Also, the total content of the liquid resin in the (A) component and the (B) component is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of non-volatile components in the resin composition, from the viewpoint of obtaining the effects of the present invention significantly, and is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more.

The biomass ratio of the resin composition is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, from the viewpoint of obtaining a significant effect of the present invention. The biomass ratio can be calculated by the method described in the examples below.

The resin composition can be produced, for example, by mixing the above-mentioned components in any order. In addition, during the process of mixing each component, heating and/or cooling may be performed by appropriately adjusting the temperature. In addition, each component may be uniformly dispersed by stirring using a stirring device such as a mixer during or after mixing. Furthermore, the resin composition may be subjected to a degassing treatment as necessary.

<Physical properties and applications of resin composition>
In the resin composition of the present invention, the contents of the (A) component and the (B) component are adjusted to be 10% by mass or more and 10% by mass or less, respectively, when the non-volatile components in the resin composition are taken as 100% by mass, and the (A) component and the (B) component are adjusted so that the biomass ratio of the liquid resin in the resin component is 40% by mass or less. Therefore, even if the biomass ratio of the resin component is increased to 5% by mass or more, it is possible to obtain a cured product having high peel strength and excellent insulation reliability. Thus, the resin composition exhibits the characteristic of having a high biomass ratio. The biomass ratio of the resin composition is preferably 1% by mass or more, more preferably 1.5% by mass or more. The upper limit is not particularly limited, but may be 100% or less. The biomass ratio can be measured according to the method described in the examples described below.

In the resin composition of the present invention, the contents of the (A) component and the (B) component are adjusted to be 10% by mass or more and 10% by mass or less, respectively, when the non-volatile components in the resin composition are taken as 100% by mass, and the (A) component and the (B) component are adjusted so that the biomass ratio of the liquid resin in the resin component is 40% by mass or less. Therefore, the cured product exhibits the property of excellent peel strength between the resin composition and a conductor layer such as copper foil. Specifically, a resin varnish is applied to a copper foil to form a resin composition layer on the copper foil. The resin composition is cured to obtain a sample having a cured product of the resin composition layer on the copper foil. The peel strength is measured using this sample. At this time, the peel strength is preferably 0.3 kgf/cm or more, more preferably 0.4 kgf/cm or more, and even more preferably 0.5 kgf/cm or more. There is no particular limit to the upper limit, but it may be 10 kgf/cm or less. The peel strength between the copper foil and the copper foil can be measured according to the method described in the examples below.

In the resin composition of the present invention, the contents of the (A) and (B) components are adjusted to be 10% by mass or more and 10% by mass or less, respectively, when the non-volatile components in the resin composition are taken as 100% by mass, and the (A) and (B) components are adjusted so that the biomass ratio of the liquid resin in the resin component is 40% by mass or less, so that the cured product exhibits excellent peel strength between the plated conductor layer. Specifically, after the resin composition is cured, the cured resin composition is roughened. The roughened surface is copper plated to form a conductor layer on the cured resin composition to obtain a sample. The peel strength is measured using this sample. At this time, the peel strength is preferably 0.2 kgf/cm or more, more preferably 0.3 kgf/cm or more, and even more preferably 0.4 kgf/cm or more. There is no particular limit to the upper limit, but it may be 10 kgf/cm or less. The peel strength between the plated conductor layer can be measured according to the method described in the examples below.

In the resin composition of the present invention, the contents of the (A) component and the (B) component are adjusted to be 10% by mass or more and 10% by mass or less, respectively, when the non-volatile components in the resin composition are 100% by mass, and the (A) component and the (B) component are adjusted so that the biomass ratio of the liquid resin in the resin component is 40% by mass or less, so that the cured product exhibits excellent insulation reliability. Specifically, the resin composition is laminated on a polyimide film on which a comb-tooth electrode is formed, and the resin composition is cured to obtain a sample. The insulation resistance value is measured using this sample. At this time, the insulation resistance value is preferably 1.0 x 10 ⁸ Ω or more. The upper limit is not particularly limited, but may be 1.0 x 10 ²⁰ Ω or less. The insulation reliability can be measured according to the method described in the examples described below.

The resin composition of the present invention usually exhibits excellent lamination properties. Specifically, the resin composition is laminated onto a glass cloth-based epoxy resin double-sided copper-clad laminate conductor having a comb-tooth conductor pattern with a conductor thickness of 35 μm, and then heat-cured to form an insulating layer. The unevenness difference between the conductor and other parts of the insulating layer is determined by a numerical value obtained using a non-contact surface roughness meter. At this time, the unevenness difference between the conductor and other parts is usually 2.0 μm or less. The lamination properties can be measured according to the method described in the examples below.

The resin composition of the present invention is suitable as a resin composition for insulating purposes, and is particularly suitable as a resin composition for forming an insulating layer. Thus, for example, the resin composition is suitable as a resin composition for forming an insulating layer of a printed wiring board (resin composition for forming an insulating layer of a printed wiring board). The resin composition is suitable as a resin composition for forming an interlayer insulating layer of a printed wiring board (resin composition for forming an interlayer insulating layer of a printed wiring board). The resin composition is also suitable as a resin composition for forming an insulating layer for forming a conductor layer (including a rewiring layer) formed on an insulating layer (resin composition for forming an insulating layer for forming a conductor layer). The resin composition can also be used in a wide range of applications in which the resin composition can be used, such as resin sheets, sheet-like laminate materials such as prepregs, solder resists, underfill materials, die bonding materials, semiconductor encapsulants, hole-filling resins, component-embedding resins, multi-chip packages, package-on-packages, wafer-level packages, panel-level packages, and system-in-packages.

Furthermore, for example, when a semiconductor chip package is manufactured through the following steps (1) to (6), the resin composition according to the present embodiment is also suitable as a resin composition for forming a rewiring formation layer as an insulating layer for forming a rewiring layer (resin composition for forming a rewiring formation layer) and as a resin composition for sealing a semiconductor chip (resin composition for sealing a semiconductor chip). When a semiconductor chip package is manufactured, a rewiring layer may be further formed on the sealing layer.
(1) A step of laminating a temporary fixing film on a substrate;
(2) A step of temporarily fixing a semiconductor chip on a temporary fixing film;
(3) forming an encapsulation layer on the semiconductor chip;
(4) peeling the substrate and the temporary fixing film from the semiconductor chip;
(5) forming a rewiring formation layer as an insulating layer on the surface of the semiconductor chip from which the base material and the temporary fixing film have been peeled off; and (6) forming a rewiring layer as a conductor layer on the rewiring formation layer.

The above-mentioned resin composition can also be used when the printed wiring board is a circuit board with built-in components.

[Resin sheet]
The resin sheet of the present invention includes a support and a resin composition layer formed from the resin composition of the present invention provided on the support.

The thickness of the resin composition layer is preferably 100 μm or less, more preferably 75 μm or less, and even more preferably 50 μm or less, from the viewpoint of making the printed wiring board thinner and being able to provide a cured product with excellent insulating properties even if the cured product of the resin composition is a thin film. The lower limit of the thickness of the resin composition layer is not particularly limited, but can usually be 5 μm or more.

Examples of the support include films made of plastic materials, metal foils, and release paper, with films made of plastic materials and metal foils being preferred.

When a film made of a plastic material is used as the support, examples of the plastic material include polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN"), polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylics such as polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred, with inexpensive polyethylene terephthalate being particularly preferred.

When a metal foil is used as the support, examples of the metal foil include copper foil and aluminum foil, with copper foil being preferred. As the copper foil, a foil made of a single metal, copper, or an alloy of copper and another metal (e.g., tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used.

The support may be subjected to a matte treatment, corona treatment, or antistatic treatment on the surface that is to be bonded to the resin composition layer.

As the support, a support with a release layer having a release layer on the surface to be bonded to the resin composition layer may be used. Examples of the release agent used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. The support with a release layer may be a commercially available product, such as "SK-1", "AL-5", and "AL-7" manufactured by Lintec Corporation, "Lumirror T60" manufactured by Toray Industries, "Purex" manufactured by Teijin Limited, and "Unipeel" manufactured by Unitika Limited, which are PET films having a release layer mainly composed of an alkyd resin-based release agent.

The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, and more preferably in the range of 10 μm to 60 μm. When using a support with a release layer, it is preferable that the thickness of the entire support with the release layer is in the above range.

In one embodiment, the resin sheet may further include other layers as necessary. Examples of such other layers include a protective film similar to the support provided on the surface of the resin composition layer that is not bonded to the support (i.e., the surface opposite the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to suppress adhesion of dirt and the like and scratches on the surface of the resin composition layer.

The resin sheet can be produced, for example, by preparing a resin varnish by dissolving the resin composition in an organic solvent, applying this resin varnish onto a support using a die coater or the like, and then drying it to form a resin composition layer.

Examples of organic solvents include ketones such as acetone, methyl ethyl ketone (MEK), and cyclohexanone; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; and amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone. The organic solvents may be used alone or in combination of two or more.

Drying may be performed by known methods such as heating or blowing hot air. There are no particular limitations on the drying conditions, but drying is performed so that the content of organic solvent in the resin composition layer is 10% by mass or less, preferably 5% by mass or less. Although it varies depending on the boiling point of the organic solvent in the resin varnish, for example, when using a resin varnish containing 30% by mass to 60% by mass of organic solvent, the resin composition layer can be formed by drying at 50°C to 150°C for 3 to 10 minutes.

The resin sheet can be stored in a roll. If the resin sheet has a protective film, it can be used by peeling off the protective film.

[Printed wiring board]
A printed wiring board according to one embodiment of the present invention includes an insulating layer formed of a cured product obtained by curing the above-described resin composition.

The printed wiring board can be produced, for example, by using the above-mentioned resin sheet by a method including the following steps (I) and (II).
(I) a step of laminating a resin sheet on an inner layer substrate so that a resin composition layer of the resin sheet is bonded to the inner layer substrate; and (II) a step of curing the resin composition layer to form an insulating layer.

The "inner layer substrate" used in step (I) is a member that will be the substrate of the printed wiring board, and examples thereof include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, and thermosetting polyphenylene ether substrates. The substrate may have a conductor layer on one or both sides, and the conductor layer may be patterned. An inner layer substrate having a conductor layer formed on one or both sides of the substrate may be called an "inner layer circuit substrate." In addition, intermediate products on which an insulating layer and/or a conductor layer is to be formed during the manufacture of a printed wiring board are also included in the "inner layer substrate." When the printed wiring board is a component-embedded circuit board, an inner layer substrate with a component embedded may be used.

The lamination of the inner layer substrate and the resin sheet can be carried out, for example, by heat-pressing the resin sheet to the inner layer substrate from the support side. Examples of the member for heat-pressing the resin sheet to the inner layer substrate (hereinafter also referred to as the "heat-pressing member") include a heated metal plate (such as a SUS panel) or a metal roll (such as a SUS roll). Note that rather than pressing the heat-pressing member directly onto the resin sheet, it is preferable to press it via an elastic material such as heat-resistant rubber so that the resin sheet can sufficiently follow the surface irregularities of the inner layer substrate.

The lamination of the inner layer substrate and the resin sheet may be performed by a vacuum lamination method. In the vacuum lamination method, the heat-pressure bonding temperature is preferably in the range of 60°C to 160°C, more preferably in the range of 80°C to 140°C, the heat-pressure bonding pressure is preferably in the range of 0.098MPa to 1.77MPa, more preferably in the range of 0.29MPa to 1.47MPa, and the heat-pressure bonding time is preferably in the range of 20 seconds to 400 seconds, more preferably in the range of 30 seconds to 300 seconds. The lamination may be performed under reduced pressure conditions, preferably at a pressure of 26.7hPa or less.

Lamination can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminators include a vacuum pressure laminator manufactured by Meiki Seisakusho Co., Ltd., a vacuum applicator manufactured by Nikko Materials Co., Ltd., and a batch-type vacuum pressure laminator.

After lamination, the laminated resin sheet may be smoothed under atmospheric pressure, for example by pressing a thermocompression member from the support side. The pressing conditions for the smoothing treatment may be the same as the thermocompression conditions for the lamination. The smoothing treatment may be performed using a commercially available laminator. Note that lamination and smoothing treatment may be performed consecutively using the commercially available vacuum laminator.

The support may be removed between steps (I) and (II), or after step (II).

In step (II), the resin composition layer is cured to form an insulating layer made of a cured product of the resin composition. The curing conditions for the resin composition layer are not particularly limited, and the conditions employed for forming an insulating layer of a printed wiring board may be used. The resin composition layer may be cured by irradiation with active energy rays such as ultraviolet rays, but is usually thermally cured by heating.

For example, the thermal curing conditions for the resin composition layer vary depending on the type of resin composition, but in one embodiment, the curing temperature is preferably 120°C to 240°C, more preferably 150°C to 220°C, and even more preferably 170°C to 210°C. The curing time is preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, and even more preferably 15 minutes to 100 minutes.

Before the resin composition layer is thermally cured, the resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermally curing the resin composition layer, the resin composition layer may be preheated at a temperature of 50°C to 120°C, preferably 60°C to 115°C, and more preferably 70°C to 110°C for 5 minutes or more, preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes, and even more preferably 15 minutes to 100 minutes.

The method for producing a printed wiring board may further include (III) a step of drilling holes in the insulating layer, (IV) a step of roughening the insulating layer, and (V) a step of forming a conductor layer. When the support is removed after step (II), the removal of the support may be performed between step (II) and step (III), between step (III) and step (IV), or between step (IV) and step (V). Furthermore, the formation of the insulating layer and the conductor layer in steps (I) to (V) may be repeated as necessary to form a multilayer wiring board.

Step (III) is a step of drilling holes in the insulating layer, which allows holes such as via holes and through holes to be formed in the insulating layer. Step (III) may be performed using, for example, a drill, a laser, plasma, etc., depending on the composition of the resin composition used to form the insulating layer. The dimensions and shape of the holes may be appropriately determined depending on the design of the printed wiring board.

Step (IV) is a step of roughening the insulating layer. Usually, smears are also removed in this step (IV). The procedure and conditions of the roughening treatment are not particularly limited. For example, the insulating layer can be roughened by carrying out a swelling treatment using a swelling liquid, a roughening treatment using an oxidizing agent, and a neutralization treatment using a neutralizing liquid in this order.

Examples of the swelling liquid used in the roughening treatment include an alkaline solution, a surfactant solution, and the like, and an alkaline solution is preferred. As the alkaline solution, a sodium hydroxide solution and a potassium hydroxide solution are more preferred. Examples of commercially available swelling liquids include "Swelling Dip Securigans P" and "Swelling Dip Securigans SBU" manufactured by Atotech Japan. The swelling treatment using the swelling liquid is not particularly limited, but can be performed by, for example, immersing the insulating layer in a swelling liquid at 30°C to 90°C for 1 to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling liquid at 40°C to 80°C for 5 to 15 minutes.

The oxidizing agent used in the roughening treatment may be, for example, an alkaline permanganate solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. The roughening treatment using an oxidizing agent such as an alkaline permanganate solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60°C to 100°C for 10 to 30 minutes. The concentration of permanganate in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Commercially available oxidizing agents include, for example, alkaline permanganate solutions such as "Concentrate Compact CP" and "Dosing Solution Securigans P" manufactured by Atotech Japan.

The neutralizing solution used in the roughening treatment is preferably an acidic aqueous solution, and a commercially available product is, for example, "Reduction Solution Securigant P" manufactured by Atotech Japan. Treatment with a neutralizing solution can be carried out by immersing the surface that has been roughened with an oxidizing agent in a neutralizing solution at 30°C to 80°C for 5 to 30 minutes. From the standpoint of workability, etc., it is preferable to immerse the object that has been roughened with an oxidizing agent in a neutralizing solution at 40°C to 70°C for 5 to 20 minutes.

In one embodiment, the arithmetic mean roughness Ra of the insulating layer surface after the roughening treatment may be preferably 500 nm or less, more preferably less than 200 nm, even more preferably 100 nm or less, and even more preferably less than 100 nm. The lower limit is not particularly limited, and may be, for example, 1 nm or more, 2 nm or more, etc. The root mean square roughness (Rq) of the insulating layer surface after the roughening treatment is preferably 500 nm or less, more preferably 400 nm or less, and even more preferably 300 nm or less. The lower limit is not particularly limited, and may be, for example, 1 nm or more, 2 nm or more, etc. The arithmetic mean roughness (Ra) and root mean square roughness (Rq) of the insulating layer surface can be measured using a non-contact surface roughness meter.

Step (V) is a step of forming a conductor layer, and the conductor layer is formed on the insulating layer. The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer contains one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. The conductor layer may be a single metal layer or an alloy layer, and examples of the alloy layer include layers formed from alloys of two or more metals selected from the above group (e.g., nickel-chromium alloy, copper-nickel alloy and copper-titanium alloy). Among these, from the viewpoints of versatility in forming the conductor layer, cost, ease of patterning, etc., a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or an alloy layer of a nickel-chromium alloy, a copper-nickel alloy, or a copper-titanium alloy is preferred, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or an alloy layer of a nickel-chromium alloy is more preferred, and a single metal layer of copper is even more preferred.

The conductor layer may be a single-layer structure, or a multi-layer structure in which two or more single metal layers or alloy layers made of different types of metals or alloys are laminated. When the conductor layer has a multi-layer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc, or titanium, or an alloy layer of a nickel-chromium alloy.

The thickness of the conductor layer depends on the desired printed wiring board design, but is generally between 3 μm and 35 μm, preferably between 5 μm and 30 μm.

The conductor layer is preferably formed by plating. For example, the surface of the insulating layer can be plated by a semi-additive method, a full-additive method, or the like to form a conductor layer having a desired wiring pattern. From the viewpoint of ease of production, it is preferable to form the conductor layer by a semi-additive method. Below, an example of forming a conductor layer by a semi-additive method is shown.

A plating seed layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern is formed on the formed plating seed layer to expose a portion of the plating seed layer corresponding to the desired wiring pattern. A metal layer is formed on the exposed plating seed layer by electrolytic plating, and the mask pattern is then removed. Thereafter, unnecessary plating seed layer is removed by etching or the like, and a conductor layer having the desired wiring pattern can be formed.

[Semiconductor device]
A semiconductor device according to an embodiment of the present invention includes the above-mentioned printed wiring board. This semiconductor device can be manufactured using the above-mentioned printed wiring board.

Semiconductor devices include various semiconductor devices used in electrical appliances (e.g., computers, mobile phones, digital cameras, televisions, etc.) and vehicles (e.g., motorcycles, automobiles, trains, ships, aircraft, etc.).

The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the following examples. In the following description, "parts" and "%" representing amounts mean "parts by mass" and "% by mass", respectively, unless otherwise specified. Furthermore, the operations described below were carried out in an environment of normal temperature and pressure, unless otherwise specified.

Synthesis Example 1: Synthesis of Thermoplastic Elastomer
In a reaction vessel, 69 g of bifunctional hydroxyl group-terminated polybutadiene ("G-3000" manufactured by Nippon Soda Co., Ltd., number average molecular weight = 3000, hydroxyl group equivalent = 1800 g / eq., biomass ratio 0 mass%), 40 g of aromatic hydrocarbon mixed solvent ("IPZOL 150" manufactured by Idemitsu Kosan Co., Ltd.), and 0.005 g of dibutyltin laurate (biomass ratio 0 mass%) were added and mixed to dissolve uniformly. When it became uniform, the temperature was raised to 60 ° C., and 8 g of isophorone diisocyanate ("IPDI" manufactured by Evonik Japan Co., Ltd., isocyanate group equivalent = 113 g / eq., biomass ratio 0 mass%) was added while stirring, and the reaction was carried out for about 3 hours.

Next, 23 g of cresol novolak resin (DIC "KA-1160", hydroxyl equivalent = 117 g/eq., biomass ratio 0 mass%) and 60 g of ethyl diglycol acetate (Daicel) were added to the reaction product, and the temperature was raised to 150°C while stirring, and the reaction was carried out for about 10 hours. The disappearance of the NCO peak at 2250 cm ^-1 was confirmed by FT-IR. The disappearance of the NCO peak was regarded as the end point of the reaction, and the reaction product was cooled to room temperature. The reaction product was then filtered through a 100-mesh filter cloth to obtain a thermoplastic elastomer having a butadiene structure and a phenolic hydroxyl group (phenolic hydroxyl group-containing butadiene resin: non-volatile component 50 mass%, biomass ratio 0 mass%). The number average molecular weight of the thermoplastic elastomer was 5900, and the glass transition temperature was -7°C.

<Synthesis Example 2: Synthesis of active ester compound>
In a 0.3-liter four-necked round flask equipped with a stirrer, a thermometer, a dropping funnel, and a nitrogen gas inlet, 11.4 g of dicyclopentadiene-phenol polyadduct ("J-DPP85" manufactured by JFE Chemical Corporation, hydroxyl equivalent 165 g/eq.), 4.98 g of 1-naphthol, 10.0 g of 2,5-furandicarboxylic acid chloride, 0.026 g of tetra-n-butylammonium bromide, and 50 g of toluene were added, and the mixture was stirred while blowing in nitrogen gas and heated to 30°C to dissolve. 16.6 g of a 25% aqueous solution of caustic soda was added dropwise while being careful not to generate heat so that the temperature would ultimately rise to 60°C. The time required for the dropwise addition was 15 minutes. After stirring at 60°C for another hour, 25 g of distilled water was added and stirred, and the aqueous layer was discarded. The organic layer was further washed three times by the same operation. The organic layer was dried over sodium sulfate, the drying agent was filtered off, and then a part of the solvent was distilled off from the resulting solution to obtain 24.7 g of the target active ester compound containing 45% by mass of toluene. The active ester compound was as follows. n represents the number of repetitions and satisfies 0≦n≦8.

Synthesis Example 3: Synthesis of active ester compound
In a 0.3-liter four-necked round flask equipped with a stirrer, a thermometer, a dropping funnel, and a nitrogen gas inlet, 20.0 g of bisphenol A (hydroxyl equivalent: 114 g/eq.), 8.1 g of phenol, 25.0 g of 2,5-furandicarboxylic acid chloride, 0.053 g of tetra-n-butylammonium bromide, and 70 g of toluene were added, and the mixture was stirred while blowing in nitrogen gas and heated to 30°C to dissolve. 48 g of a 25% aqueous solution of caustic soda was added dropwise while being careful not to generate heat, so that the temperature would ultimately rise to 60°C. The time required for the dropwise addition was 15 minutes. After stirring for another hour at 60°C, 25 g of distilled water was added and stirred, and the aqueous layer was discarded. The organic layer was further washed three times in the same manner. The organic layer was dried over sodium sulfate, the drying agent was filtered off, and then a part of the solvent was distilled off from the obtained solution to obtain a target active ester compound having a solid concentration of 45 mass% (number average molecular weight 917, active group equivalent weight approximately 153 g/eq., biomass ratio >99 mass%, non-volatile component ratio 45%) (wherein n represents a number in the range of 0≦n≦8).

Synthesis Example 4: Synthesis of active ester compound
In Synthesis Example 2,
1) 4.98 g of 1-naphthol was replaced with 8.0 g of camphene-modified phenol (Yasuhara Chemical Co., Ltd.'s "YS Resin CP", hydroxyl group equivalent 220 g/eq.);
2) 11.4 g of dicyclopentadiene-phenol polyadduct ("J-DPP85" manufactured by JFE Chemical Corporation, hydroxyl equivalent 165 g/eq.) was changed to 7.9 g of bisphenol A (hydroxyl equivalent 114 g/eq.).
Except for the above, the same procedure as in Synthesis Example 2 was followed to obtain the target active ester compound (number average molecular weight: 1,348, active group equivalent: approximately 225 g/eq., biomass ratio: 88 mass%, non-volatile component ratio: 55%) (wherein n represents a number in the range of 0≦n≦8).

Synthesis Example 5: Synthesis of active ester compound
In Synthesis Example 2,
1) 4.98 g of 1-naphthol was replaced with 3.3 g of phenol.
2) 11.4 g of dicyclopentadiene-phenol polyadduct ("J-DPP85" manufactured by JFE Chemical Corporation, hydroxyl equivalent: 165 g/eq.) was changed to 14 g of benzyl-modified bisphenol A (d and e are in the range of 1≦d+e≦4).
Except for the above, the same procedure as in Synthesis Example 2 was followed to obtain an active ester compound (a toluene solution having a number average molecular weight of 433, an active group equivalent of about 217 g/eq., a biomass ratio of 71 mass% (n=1 and d+e=3), and a non-volatile component ratio of 46%) (wherein n is 0≦n≦8, and d and e are numbers within the range of 1≦d+e≦4).

Example 1
20 parts of biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269 g/eq., biomass ratio of 0 mass%), 10 parts of bixylenol type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 194 g/eq., biomass ratio of 0 mass%), and 15 parts of naphthalene type epoxy resin ("ESN475V" manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent of about 332 g/eq., biomass ratio of 0 mass%) were added with 60 parts of methyl ethyl ketone (MEK), and dissolved by heating with stirring. This was cooled to room temperature to prepare an epoxy resin solution composition. To this epoxy resin solution, 5 parts of a triazine skeleton-containing phenolic curing agent (DIC Corporation's "LA-3018-50P", 2-methoxypropanol solution with active group equivalent of about 151 g/eq., biomass ratio of 0 mass%, and non-volatile component ratio of 50%), 30 parts of the active ester compound obtained in Synthesis Example 2 (toluene solution with active ester group equivalent of about 215 g/eq., biomass ratio of 28.4 mass%, and non-volatile component ratio of 55%), and 10 parts of a phenoxy resin (Mitsubishi Chemical Corporation's "YX7553BH30", biomass ratio of 0 A resin varnish was prepared by mixing 8 parts of a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0 mass% and a nonvolatile content of 30 mass%, 180 parts of biomass silica ("Ethical Silica" manufactured by MIT, average particle size 3.7 μm, biomass ratio 100 mass%) that had been surface-treated with a silane coupling agent ("KBM-573" manufactured by Shin-Etsu Chemical Co., Ltd.), and 4 parts of an amine-based curing accelerator (4-dimethylaminopyridine (DMAP), biomass ratio 0 mass%, MEK solution with a solids content of 5 mass%) and dispersing the mixture uniformly using a high-speed rotary mixer.

Next, the resin varnish was evenly applied to the release surface of the support, a polyethylene terephthalate film with release treatment ("AL5" manufactured by Lintec Corporation, thickness 38 μm), so that the resin composition layer had a thickness of 40 μm, and then dried at 80 to 120°C (average 100°C) for 5 minutes to produce a resin sheet.

Example 2
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 15 parts,
2) The amount of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0% by mass and a non-volatile content of 30% by mass) was changed from 8 parts to 12 parts,
3) 10 parts of cashew-benzoxazine resin (Tohoku Kako Co., Ltd. "CR-276", benzoxazine equivalent of about 341 g/eq., biomass ratio of 91.8% by mass) was used.
4) 5 parts of rubber particles ("Staphyloid AC3816N" manufactured by Aica Kogyo Co., Ltd., biomass ratio 0% by mass) were used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

Example 3
In Example 1,
1) The amount of naphthalene-type epoxy resin ("ESN475V" manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent: about 332 g/eq., biomass ratio: 0% by mass) was changed from 15 parts to 10 parts,
2) 5 parts of dicyclopentadiene type epoxy resin (DIC Corporation "HP7200HH", epoxy equivalent of about 283 g/eq., biomass ratio 0% by mass) was used.
3) The amount of a triazine skeleton-containing phenolic curing agent (DIC Corporation's "LA-3018-50P", active group equivalent of about 151 g/eq., biomass ratio 0 mass%, non-volatile component ratio 50% in 2-methoxypropanol solution) was changed from 5 parts to 3 parts,
4) 1 part of naphthol-type hardener ("SN-485" manufactured by Nippon Steel Chemical & Material Co., Ltd., hydroxyl equivalent of about 205 g/eq., biomass ratio of 0% by mass) was used.
5) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 15 parts,
6) The amount of biomass silica (MIT's "Ethical Silica", average particle size 3.7 μm, biomass ratio 100% by mass) surface-treated with a silane coupling agent (Shin-Etsu Chemical Co., Ltd.'s "KBM-573") was changed from 180 parts to 40 parts.
7) 140 parts of spherical silica (Admatechs'"SO-C2", average particle size 0.5 μm, biomass ratio 0 mass%) surface-treated with a silane coupling agent (Shin-Etsu Chemical's "KBM-573") was used.
8) 10 parts of cashew-benzoxazine resin ("CR-276" manufactured by Tohoku Kako Co., Ltd., benzoxazine equivalent of about 341 g/eq., biomass ratio of 91.8% by mass) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

Example 4
In Example 1,
1) The amount of naphthalene-type epoxy resin ("ESN475V" manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent: about 332 g/eq., biomass ratio: 0% by mass) was changed from 15 parts to 10 parts,
2) 5 parts of a phenolphthalimidine type epoxy resin ("WHR-991S" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: about 265 g/eq., biomass ratio: 0% by mass) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

Example 5
8 parts of bisphenol A type epoxy resin ("828EL" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 180 g/eq., biomass ratio of 0 mass%), 20 parts of biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269 g/eq., biomass ratio of 0 mass%), 15 parts of naphthalene type epoxy resin ("ESN475V" manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent of about 332 g/eq., biomass ratio of 0 mass%), 2 parts of epoxidized cardanol resin ("FE-5130" manufactured by Tohoku Kako Co., Ltd., epoxy equivalent of about 342 g/eq., biomass ratio of 83.3 mass%) were added with 40 parts of methyl ethyl ketone (MEK) and dissolved by heating with stirring. This was cooled to room temperature to prepare an epoxy resin solution composition. To this epoxy resin solution composition, 10 parts of cash-benzoxazine resin ("CR-276" manufactured by Tohoku Kako Co., Ltd., benzoxazine equivalent of about 341 g/eq., biomass ratio of 91.8% by mass), 4 parts of a phenolic hardener containing a triazine skeleton ("LA-3018-50P" manufactured by DIC Corporation, active group equivalent of about 151 g/eq., biomass ratio of 0% by mass, 2-methoxypropanol solution with a non-volatile component ratio of 50%), 2 parts of a phenolic hardener derived from a natural product (Resveratrol, phenol equivalent of about 76 g/eq., biomass ratio of 100% by mass), and the active ester compound obtained in Synthesis Example 2 (active ester group equivalent of about 215 g/eq., biomass ratio of 100% by mass) were added. A resin varnish was prepared by mixing 40 parts of a toluene solution with a biomass ratio of 28.4% and a non-volatile content of 55%, 40 parts of a phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0% and a non-volatile content of 30% by weight), 8 parts of a phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0% by weight and a non-volatile content of 30% by weight), 55 parts of spherical silica ("SO-C2" manufactured by Admatechs Co., Ltd., average particle size 0.5 μm, biomass ratio of 0% by weight) surface-treated with a silane coupling agent ("KBM-573" manufactured by Shin-Etsu Chemical Co., Ltd.), and 4 parts of an amine-based curing accelerator (4-dimethylaminopyridine (DMAP), a MEK solution with a biomass ratio of 0% by weight and a solid content of 5% by weight). The mixture was uniformly dispersed using a high-speed rotating mixer.

Next, the resin varnish was evenly applied to the release surface of the support, a polyethylene terephthalate film with release treatment ("AL5" manufactured by Lintec Corporation, thickness 38 μm), so that the resin composition layer had a thickness of 40 μm, and then dried at 80 to 120°C (average 100°C) for 5 minutes to produce a resin sheet.

Example 6
In Example 5,
Two parts of a naturally derived phenolic hardener (Resveratrol, phenol equivalent of about 76 g/eq., biomass ratio 100% by weight) was replaced with two parts of a naturally derived phenolic hardener (Curcumin, phenol equivalent of about 184 g/eq., biomass ratio 100% by weight).
A resin varnish and a resin sheet were prepared in the same manner as in Example 5 except for the above.

Example 7
In Example 2,
1) 10 parts of a bixylenol type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 194 g/eq., biomass ratio of 0 mass%) was replaced with 8 parts of epoxidized soybean oil ("Sanso Cizer E-2000H" manufactured by New Japan Chemical Co., Ltd., epoxy equivalent of about 234 g/eq., biomass ratio of 93.2 mass%),
2) 5 parts of rubber particles (Aica Kogyo Co., Ltd.'s "Staphyloid AC3816N", biomass ratio 0% by mass) were replaced with 3 parts of thermoplastic polyamide resin (Tsukuno Foods Co., Ltd.'s "Vegichem Green V335", biomass ratio 80% by mass);
3) 12 parts of a phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0 mass% and a nonvolatile content of 30 mass%) was not used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 2 except for the above.

Example 8
In Example 7, 8 parts of epoxidized soybean oil ("Sanso Cizer E-2000H" manufactured by New Japan Chemical Co., Ltd., epoxy equivalent of about 234 g/eq., biomass ratio of 93.2% by mass) were replaced with 6 parts of glycerin acrylate ("Aronix M-930" manufactured by Toa Gosei Co., Ltd., biomass ratio of 35% by mass) and 2 parts of a liquid resin derived from natural products ("β-carotene", biomass ratio of 100% by mass).
Except for the above, a resin varnish and a resin sheet were prepared in the same manner as in Example 7.

<Example 9>
10 parts of a biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269 g/eq., biomass ratio of 0 mass%), 10 parts of a naphthylene ether type epoxy resin ("HP-6000" manufactured by DIC Corporation, epoxy equivalent of about 250 g/eq., biomass ratio of 0 mass%), 15 parts of a cashew modified epoxy resin ("LITE 514SE" manufactured by Cardolite Corporation, epoxy equivalent of about 401 g/eq., biomass ratio of 91.7 mass%), 20 parts of methyl ethyl ketone (MEK), and 30 parts of 1-methoxy-2-propanol were added and heated and dissolved with stirring. This was cooled to room temperature to prepare an epoxy resin solution composition. To this epoxy resin solution, 2 parts of a triazine skeleton-containing phenolic curing agent (DIC Corporation's "LA-3018-50P", 2-methoxypropanol solution with active group equivalent of about 151 g/eq., biomass ratio of 0 mass%, and non-volatile component ratio of 50%), 10 parts of the active ester compound obtained in Synthesis Example 2 (toluene solution with active ester group equivalent of about 215 g/eq., biomass ratio of 28.4 mass%, and non-volatile component ratio of 55%), 10 parts of a cashew-modified phenolic resin (Sumitomo Bakelite Co., Ltd.'s "PR-12686F", active group equivalent of about 142 g/eq., biomass ratio of about 30 mass%), 2 parts of a shellac resin (Koyo Chemical Co., Ltd.'s "KL-1001", biomass ratio of 100 mass%), tannic acid (Sumitomo Pharma Food & Chemical Co., Ltd.'s "Biomass ratio of 100 mass%), and 10 parts of a tertiary ester compound (Sumitomo Pharma Food & Chemical Co., Ltd.'s "Biomass ratio of 100 mass%)) were added. Biomass ratio 100% by mass) 1 part, thermoplastic polyamide resin (Tsukuno Food Industry Co., Ltd. "Vegichem Green V335", biomass ratio 80% by mass) 3 parts, biomass silica (MIT Corporation "Ethical Silica", average particle size 3.7 μm, biomass ratio 100% by mass) surface-treated with a silane coupling agent (Shin-Etsu Chemical Co., Ltd. "KBM-573") 140 parts, amine-based curing accelerator (4-dimethylaminopyridine (DMAP), biomass ratio 0% by mass, MEK solution with solids of 5% by mass) 2 parts, imidazole-based curing accelerator (Shikoku Chemical Industry Co., Ltd. "1B2PZ", 1-benzyl-2-phenylimidazole, MEK solution with solids of 10% by mass) 1 part was mixed and uniformly dispersed with a high-speed rotating mixer to prepare a resin varnish.

A resin varnish was evenly applied to the release surface of a release-treated polyethylene terephthalate film ("AL5" manufactured by Lintec Corporation, thickness 38 μm) that served as a support, so that the resin composition layer was 40 μm thick, and the resin was dried at 80 to 120°C (average 100°C) for 8 minutes to produce a resin sheet.

Example 10
5 parts of a biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269 g/eq., biomass ratio of 0 mass%), 10 parts of a naphthylene ether type epoxy resin ("HP-6000" manufactured by DIC Corporation, epoxy equivalent of about 250 g/eq., biomass ratio of 0 mass%), and 5 parts of an aliphatic epoxy resin ("Denacol EX-521" manufactured by Nagase ChemteX Corporation, epoxy equivalent of 183 g/eq., biomass ratio of 50 mass%) were added to 55 parts of methyl ethyl ketone (MEK), and dissolved by heating with stirring. This was cooled to room temperature to prepare an epoxy resin solution composition. This epoxy resin solution composition was mixed with 5 parts of cash-benzoxazine resin (Tohoku Kako Co., Ltd. "CR-276", benzoxazine equivalent about 341 g/eq., biomass ratio 91.8% by mass), 40 parts of the thermoplastic elastomer obtained in Synthesis Example 1 (solid content concentration 50% by mass, biomass ratio 0% by mass), 50 parts of biomass silica (MIT Corporation "Ethical Silica", average particle size 3.7 μm, biomass ratio 100% by mass) surface-treated with a silane coupling agent (Shin-Etsu Chemical Co., Ltd. "KBM-573"), and 4 parts of an imidazole-based curing accelerator (Shikoku Kasei Corporation "1B2PZ", 1-benzyl-2-phenylimidazole, MEK solution with a solid content of 10% by mass), and uniformly dispersed using a high-speed rotating mixer to prepare a resin varnish.

A resin varnish was evenly applied to the release surface of a release-treated polyethylene terephthalate film ("AL5" manufactured by Lintec Corporation, thickness 38 μm) that served as a support, so that the resin composition layer was 40 μm thick, and then dried at 80 to 120°C (average 100°C) for 5 minutes to produce a resin sheet.

Example 11
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 20 parts,
2) 12 parts of the active ester compound obtained in Synthesis Example 3 (active group equivalent: approximately 153 g/eq., biomass ratio >99% by mass, non-volatile component ratio 45%) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

Example 12
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 20 parts,
2) 10 parts of the active ester compound obtained in Synthesis Example 4 (active group equivalent: approximately 225 g/eq., biomass ratio: 88% by mass, non-volatile component ratio: 55%) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

Example 13
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 20 parts,
2) 12 parts of the active ester compound obtained in Synthesis Example 5 (active group equivalent: approximately 217 g/eq., biomass ratio: 71 mass% (n=1 and d+e=3), non-volatile component ratio: 46% in toluene solution) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

<Example 14>
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 25 parts,
2) 3 parts of an active ester compound (BPTMC-FE manufactured by Honshu Chemical Industry Co., Ltd., active ester group equivalent of about 249 g/eq., biomass ratio of 32% by mass) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

Example 15
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 25 parts,
2) 3 parts of an active ester compound ("BP-FE" manufactured by Honshu Chemical Industry Co., Ltd., active ester group equivalent of about 187 g/eq., biomass ratio of 45% by mass) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

<Example 16>
In Example 1,
1) The amount of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was changed from 30 parts to 25 parts,
2) 3 parts of an active ester compound ("TMPBP-FE" manufactured by Honshu Chemical Industry Co., Ltd., active ester group equivalent of about 217 g/eq., biomass ratio of 36% by mass) was used.
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

<Example 17>
In Example 5,
1) 2 parts of epoxidized cardanol resin (Tohoku Kako Co., Ltd. "FE-5130", epoxy equivalent approximately 342 g/eq., biomass ratio 83.3% by mass) was changed to 2 parts of LIMONENE DIOXIDE (Cargill Corporation, epoxy equivalent approximately 96 g/eq., biomass ratio 100% by mass).
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

<Comparative Example 1>
In Example 1,
1) 30 parts of the active ester compound obtained in Synthesis Example 2 (a toluene solution having an active ester group equivalent of about 215 g/eq., a biomass ratio of 28.4% by mass, and a non-volatile component ratio of 55%) was replaced with 26 parts of an active ester compound ("HPC-8000-65T" manufactured by DIC Corporation, an active ester group equivalent of about 223 g/eq., a biomass ratio of 0% by mass, and a non-volatile component ratio of 65% in a toluene solution);
2) 180 parts of biomass silica (MIT's "Ethical Silica", average particle size 3.7 μm, biomass ratio 100% by mass) surface-treated with a silane coupling agent (Shin-Etsu Chemical Co., Ltd.'s "KBM-573") was changed to 180 parts of spherical silica (Admatechs'"SO-C2", average particle size 0.5 μm, biomass ratio 0% by mass) surface-treated with a silane coupling agent (Shin-Etsu Chemical Co., Ltd.'s "KBM-573").
A resin varnish and a resin sheet were prepared in the same manner as in Example 1 except for the above.

<Comparative Example 2>
In Comparative Example 1,
1) 180 parts of spherical silica ("SO-C2" manufactured by Admatechs, average particle size 0.5 μm, biomass ratio 0 mass%) surface-treated with a silane coupling agent ("KBM-573" manufactured by Shin-Etsu Chemical Co., Ltd.) was replaced with 50 parts of biomass silica ("Ethical Silica" manufactured by MIT, average particle size 3.7 μm, biomass ratio 100 mass%) surface-treated with a silane coupling agent ("KBM-573" manufactured by Shin-Etsu Chemical Co., Ltd.),
2) The amount of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0% by mass and a non-volatile content of 30% by mass) was changed from 8 parts to 30 parts,
3) 8 parts of rubber particles ("Staphyloid AC3816N" manufactured by Aica Kogyo Co., Ltd., biomass ratio 0% by mass) were used.
A resin varnish and a resin sheet were prepared in the same manner as in Comparative Example 1 except for the above.

<Comparative Example 3>
In Comparative Example 2,
1) The amount of biphenyl-type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269 g/eq., biomass ratio 0% by mass) was changed from 20 parts to 8 parts,
2) The amount of a triazine skeleton-containing phenolic curing agent (DIC Corporation's "LA-3018-50P", active group equivalent of about 151 g/eq., biomass ratio 0 mass%, non-volatile component ratio 50% in 2-methoxypropanol solution) was changed from 5 parts to 2 parts,
3) The amount of biomass silica (MIT's "Ethical Silica", average particle size 3.7 μm, biomass ratio 100% by mass) surface-treated with a silane coupling agent (Shin-Etsu Chemical Co., Ltd.'s "KBM-573") was changed from 50 parts to 80 parts.
4) The amount of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of MEK and cyclohexanone with a biomass ratio of 0% by mass and a non-volatile content of 30% by mass) was changed from 30 parts to 40 parts,
5) The amount of rubber particles (Aica Kogyo Co., Ltd. "Staphyloid AC3816N", biomass ratio 0% by mass) was changed from 8 parts to 5 parts.
6) The amount of amine-based curing accelerator (4-dimethylaminopyridine (DMAP), MEK solution with 0% biomass and 5% solids) was changed from 4 parts to 2 parts.
7) 10 parts of a bixylenol type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent about 194 g/eq., biomass ratio 0 mass%), 15 parts of a naphthalene type epoxy resin ("ESN475V" manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent about 332 g/eq., biomass ratio 0 mass%), and 26 parts of an active ester compound ("HPC-8000-65T" manufactured by DIC Corporation, active ester group equivalent about 223 g/eq., biomass ratio 0 mass%, toluene solution with non-volatile component ratio of 65%) were not used.
Except for the above, a resin varnish and a resin sheet were prepared in the same manner as in Comparative Example 2.

<Comparative Example 4>
In Example 7,
1) The amount of biphenyl-type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269 g/eq., biomass ratio of 0% by mass) was changed from 20 parts to 10 parts,
2) The amount of naphthalene-type epoxy resin ("ESN475V" manufactured by Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent: about 332 g/eq., biomass ratio: 0% by mass) was changed from 15 parts to 5 parts,
3) 8 parts of epoxidized soybean oil ("Sanso Cizer E-2000H" manufactured by New Japan Chemical Co., Ltd., epoxy equivalent of about 234 g/eq., biomass ratio of 93.2% by mass) was replaced with 20 parts of an aliphatic epoxy resin ("Denacol EX-521" manufactured by Nagase ChemteX Corporation, epoxy equivalent of 183 g/eq., biomass ratio of 50% by mass);
4) 10 parts of epoxidized cardanol resin (Tohoku Kako Co., Ltd. "FE-5130", epoxy equivalent: about 342 g/eq., biomass ratio: 83.3% by mass) was used.
5) 3 parts of thermoplastic polyamide resin ("Vegichem Green V335" manufactured by Tsuno Foods Industries Co., Ltd., biomass ratio 80% by mass) was changed to 8 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, biomass ratio 0% by mass, 1:1 solution of MEK and cyclohexanone with non-volatile content of 30% by mass).
Except for the above, a resin varnish and a resin sheet were prepared in the same manner as in Example 7.

<Measurement of peel strength between copper foil>
(1) Preparation of Evaluation Substrate A The resin varnish prepared in the Examples, Comparative Examples, and Reference Examples was applied to a copper foil ("JDLC" manufactured by JX Metals, thickness 12 μm, 240 mm square) using a die coater so that the thickness of the resin composition layer after drying was 40 μm, and dried for 10 minutes at 80° C. to 120° C. (average 100° C.) to obtain a resin-attached copper foil sheet. This resin-attached copper foil sheet was laminated to both sides of the laminate using a batch-type vacuum pressure laminator (manufactured by Meiki Co., Ltd., MVLP-500) so that the resin composition layer was in contact with both sides of the laminate. The lamination was performed by reducing the pressure for 30 seconds to 13 hPa or less, and then pressing for 30 seconds at 100° C. and a pressure of 0.74 MPa. The resin-attached copper foil sheet was laminated on the laminate under the curing conditions of 180° C. and 90 minutes to cure the resin composition layer to form an insulating layer. This is called "Evaluation Substrate A".

(2) Measurement of peel strength between copper foil A cut having a width of 10 mm and a length of 100 mm was made in the copper foil of evaluation substrate A, and one end of the cut was peeled off and held with a gripper (Autocom type testing machine "AC-50C-SL" manufactured by TSE Corporation). The load (kgf/cm) when 20 mm was peeled off in the vertical direction at room temperature at a speed of 50 mm/min was measured in accordance with JIS C6481.

<Measurement of plating peel strength>
(1) Preparation of Evaluation Substrate B A glass cloth-based epoxy resin double-sided copper-clad laminate (copper foil thickness 18 μm, substrate thickness 0.8 mm, Panasonic "R1515A") having copper foil on the surface was prepared. The copper foil on the surface of this inner layer substrate was etched with a microetching agent (Mech "CZ8101") with a copper etching amount of 1 μm to perform a roughening treatment. After that, it was dried at 190 ° C for 30 minutes to prepare a base-treated inner layer substrate.

The resin sheets obtained in the examples, comparative examples, and reference examples were laminated on both sides of the substrate-treated inner layer substrate using a batch-type vacuum pressure laminator (a two-stage build-up laminator "CVP700" manufactured by Nikko Materials Co., Ltd.) so that the resin composition layer was bonded to the substrate-treated inner layer substrate. This lamination was performed by reducing the pressure for 30 seconds to 13 hPa or less, and then pressing at a temperature of 100°C and a pressure of 0.74 MPa for 30 seconds. The laminated resin sheet was then heat-pressed at atmospheric pressure, 100°C, and a pressure of 0.5 MPa for 60 seconds to smooth it. This was then placed in a 130°C oven and heated for 30 minutes, and then transferred to a 170°C oven and heated for 30 minutes to obtain a substrate with a cured resin.

After peeling off the support from the substrate with the cured resin, the substrate was immersed in a swelling solution, Swelling Dip Securigant P, manufactured by Atotech Japan, at 60° C. for 10 minutes. Next, the substrate was immersed in a roughening solution, Concentrate Compact P, manufactured by Atotech Japan (aqueous solution of KMnO ₄ : 60 g/L, NaOH: 40 g/L), at 80° C. for 20 minutes. Finally, the substrate was immersed in a neutralizing solution, Reduction Solution Securigant P, manufactured by Atotech Japan, at 40° C. for 5 minutes. Next, the substrate was immersed in an electroless plating solution containing PdCl ₂ at 40° C. for 5 minutes, and then in an electroless copper plating solution at 25° C. for 20 minutes. After heating at 150° C. for 30 minutes to perform an annealing treatment, an etching resist was formed, and after forming a pattern by etching, copper sulfate electrolytic plating was performed to form a conductor layer with a thickness of 30 μm. Next, an annealing treatment was performed at 200° C. for 60 minutes, and the obtained substrate was used as an evaluation substrate B.

(2) Measurement of plating peel strength A cut having a width of 10 mm and a length of 100 mm was made in the conductor layer of evaluation substrate B, and one end of the cut was peeled off and held with a gripper (Autocom type testing machine "AC-50C-SL" manufactured by TSE Corporation). The load (kgf/cm) when 20 mm was peeled off in the vertical direction at room temperature at a speed of 50 mm/min was measured in accordance with JIS C6481.

<Evaluation of insulation reliability>
(1) Preparation of Laminate for Insulation Reliability Evaluation The resin sheets obtained in the Examples, Comparative Examples, and Reference Examples were laminated on a polyimide film having a comb-tooth electrode (line/space = 15 μm/15 μm) formed thereon, so that the resin composition layer of the resin sheet was in contact with the copper circuit surface of the comb-tooth electrode, using a batch-type vacuum pressure laminator (MVLP-500, manufactured by Meiki Co., Ltd.). The lamination was performed by reducing the pressure for 30 seconds to 13 hPa or less, and then pressing for 30 seconds at 100 ° C. and a pressure of 0.74 MPa. After peeling off the PET film of the support, the laminate was thermally cured at 180 ° C. for 90 minutes to obtain a laminate for insulation reliability evaluation.

(2) Evaluation of Insulation Reliability This evaluation laminate was placed in a highly accelerated life test apparatus ("PM422" manufactured by Kusumoto Chemical Industries, Ltd.) and subjected to an application of a voltage of 3.3 V at 130°C, 85% RH for 100 hours, after which the insulation resistance value of the evaluation laminate was measured and evaluated according to the following criteria.
◯: Insulation resistance value is 1.0×10 ⁸ Ω or more.
×: Insulation resistance value is less than 1.0×10 ⁸ Ω.

<Evaluation of Lamination Properties>
The resin sheets obtained in the examples, comparative examples, and reference examples were laminated on a comb-shaped conductor pattern with a conductor thickness of 35 μm and L (line: wiring width) / S (space: interval width) = 160 μm / 160 μm using a batch type vacuum pressure laminator (MVLP-500, manufactured by Meiki Co., Ltd.). The lamination was performed by reducing the pressure for 30 seconds to 13 hPa or less, and then pressing for 30 seconds at 100 ° C. and a pressure of 0.74 MPa. The resin composition was then cured under curing conditions of 130 ° C., 30 minutes, and further 170 ° C., 30 minutes to form an insulating layer, and then the PET film, which was the support, was peeled off. The difference in unevenness (Rt: maximum peak-to-valley) between the conductor and other parts of the insulating layer was determined using a non-contact surface roughness meter (WYKO NT3300 manufactured by B-CO Instruments) in VSI mode with a 10x lens to obtain a measurement range of 1.2 mm x 0.91 mm, and was evaluated according to the following criteria.
◯: The difference in unevenness between the conductor and other parts is 2.0 μm or less.
×: The difference in unevenness between the conductor and other portions is more than 2.0 μm.

<Calculation of biomass ratio>
The Japan Organic Resources Association defines "biomass" as any organic resource derived from a renewable organism, excluding fossil resources (but including inorganic resources such as shells that are produced directly by organisms). Based on this definition, the biomass ratio of the raw materials used in the blend was calculated using the following formula. The biomass ratio in the resin component was also evaluated using the following criteria.
Biomass ratio (mass%)=(weight of biological components in a substance/weight of substance)×100

<Determination of biomass ratio in resin component>
Based on the above-mentioned method for calculating the biomass ratio, the biomass ratio in the resin components excluding the inorganic filler component in the resin composition was calculated and judged according to the following criteria.
◯: Biomass ratio in the resin component is 5% by mass or more. ×: Biomass ratio in the resin component is less than 5% by mass.

*In the table, the contents of components (A) to (C) represent the contents when the total amount of non-volatile components in the resin composition is taken as 100 mass %.

Claims (9)

A resin composition comprising: (A) a thermosetting resin; and (B) a thermoplastic resin,
The component (A) contains an epoxy resin (A-1),
The component (A-1) contains a solid epoxy resin and a liquid epoxy resin,
The content of the component (A) is 10% by mass or more when the total amount of non-volatile components in the resin composition is 100% by mass,
the content of the liquid epoxy resin contained in the component (A-1) is 10% by mass or less, based on 100% by mass of the non-volatile components in the resin composition;
The content of the (B) component is 10% by mass or less, when the total amount of non-volatile components in the resin composition is 100% by mass,
The biomass ratio of the resin component in the resin composition is 5.5% by mass or more,
A resin composition, wherein a biomass ratio of a liquid resin in a resin component is 40 mass% or less. The resin composition according to claim 1, further comprising (C) an inorganic filler. The resin composition according to claim 2, wherein the content of (C) inorganic filler is 20% by mass or more when the non-volatile components in the resin composition are 100% by mass. The resin composition according to claim 1, wherein (A) the thermosetting resin contains (A-2) a curing agent. The resin composition according to claim 1, wherein the liquid resin contains either (A-1) an epoxy resin or (A-2) a curing agent. The resin composition according to claim 1, which is used to form an insulating layer. A resin sheet comprising a support and a resin composition layer provided on the support, the resin composition comprising the resin composition according to any one of claims 1 to 6. A printed wiring board comprising an insulating layer formed from a cured product of the resin composition according to any one of claims 1 to 6. A semiconductor device including the printed wiring board according to claim 8.