JP7567503B2 - Propenyl group-containing composition, curable resin composition, cured product, and electric/electronic parts - Google Patents

Description

The present invention relates to a propenyl group-containing composition, a curable resin composition, a cured product, and an electric/electronic part.

Thermosetting resin compositions are used in a variety of fields as thermosetting molding materials, taking advantage of their curability. Examples include adhesives and sealants for electrical and electronic components.

As a thermosetting resin composition, a resin composition that mixes maleimide resin or epoxy resin with allylphenol, alkenylphenol, alkenylphenol ether, etc. has been proposed.

For example, Patent Documents 1 and 2 disclose compositions comprising mixtures of bismaleimide, amines, alkenylphenols, alkenylphenol ethers, etc., and disclose that the alkenylphenols are produced by rearrangement of allyl ethers of phenols.

Patent Document 3 also discloses a resin composition that has excellent heat resistance, low water absorption, and can suppress voids in the cured product, and that contains a specific propenyl group-containing resin that has a benzene ring or a naphthalene ring that has a propenyl group, and a maleimide compound that has two or more maleimide groups in one molecule.

Japanese Unexamined Patent Publication No. 181335/1986 Japanese Patent Application Publication No. 4-227931 JP 2019-019149 A

Traditionally, most semiconductors have been used in LSIs and other devices that require relatively small currents and power, but in recent years, there has been rapid development of power semiconductors, which use semiconductors to control motors, lighting, and other devices and convert power. As a result, there is a demand for semiconductors and semiconductor encapsulation materials that can be used with higher power and current than before, and semiconductor encapsulation materials are required to have higher heat resistance, lower viscosity, and long-term reliability than before.

The cured product obtained by curing the resin composition containing the propenyl group-containing resin and the maleimide compound described in Patent Document 3 was not satisfactory in terms of heat resistance, low viscosity, and long-term reliability as a semiconductor encapsulant used in the above-mentioned applications.

The present invention aims to provide a propenyl group-containing composition capable of providing a curable resin composition that has low viscosity and gives a cured product with excellent heat resistance and long-term reliability, a curable resin composition using the same, and a cured product and an electric/electronic part made from the same.

As a result of intensive research to solve the above problems, the inventors focused on the temperature range at which the maleimide resin hardening reaction begins, and, based on the assumption that by controlling the hardening start temperature, it is possible to achieve low viscosity and long-term reliability while exhibiting high heat resistance, even when the hardening reaction is carried out at a low temperature, they discovered that the skeleton and purity of the propenyl group-containing compound blended with the maleimide resin can be important control factors in controlling the hardening start temperature. They then discovered that a specific propenyl group-containing composition can achieve low viscosity and long-term reliability while exhibiting high heat resistance, even when the hardening temperature is low, and have completed the present invention.

That is, the gist of the present invention lies in the following [1] to [8].

[1] A propenyl group-containing composition containing a compound represented by the following formula (1), the content of the compound represented by formula (1) being 80.0 to 99.9 mass %.

(In the above formula (1), X is a divalent linking group selected from a direct bond, -SO ₂ -, -O-, -CO-, -C(CF ₃ ) ₂ -, -S-, and an aliphatic hydrocarbon group having 1 to 20 carbon atoms. ^{R 1} and R ² are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen atom, and may be the same or different.)

[2] The propenyl group-containing composition according to [1], containing 0.1 to 20.0 mass% of a compound represented by the following formula (2):

(In the above formula (2), X, R ¹ and R ² are defined as in the above formula (1).)

[3] The propenyl group-containing composition according to [1] or [2], in which the proportion of trans isomers in which all propenyl groups are in the trans form among the compounds represented by formula (1) is 20 to 95%.

[4] A propenyl group-containing composition according to any one of [1] to [3], in which the proportion of cis isomers in which all propenyl groups are cis-type among the compounds represented by formula (1) is 30% or less.

[5] A propenyl group-containing composition according to any one of [1] to [4], having a melt viscosity at 150°C in the range of 0.01 to 10.0 P.

[6] A curable resin composition comprising 0.01 to 1000 parts by mass of at least one selected from the group consisting of epoxy resins, maleimide resins, phenolic resins, benzoxazine resins, cyanate ester resins, active ester resins, resins having radically polymerizable functional groups, isocyanate resins, acid anhydride resins, and carbodiimide resins, per 100 parts by mass of the propenyl group-containing composition according to any one of [1] to [5].

[7] A cured product obtained by curing the curable resin composition described in [6].

[8] An electric/electronic part comprising a cured product of the curable resin composition described in [6].

The curable resin composition of the present invention obtained by mixing the propenyl group-containing composition of the present invention with a maleimide resin, an epoxy resin, or the like, has a low viscosity and can give a cured product having high heat resistance and excellent long-term reliability.
For this reason, the propenyl group-containing composition and the curable resin composition of the present invention can provide highly reliable cured products and electrical/electronic components that have excellent electrical reliability, thermal decomposition resistance, adhesion, low moisture absorption, low elasticity, and little change in physical properties at high temperatures.

The following describes in detail an embodiment of the present invention, but the following description is merely an example of an embodiment of the present invention, and the present invention is not limited to the contents described below as long as it does not deviate from the gist of the invention. Note that in this specification, when the expression "~" is used, it is used as an expression including the numerical values or physical property values before and after it.

[Propenyl group-containing composition]
The propenyl group-containing composition of the present invention contains a compound represented by the following formula (1), and is characterized in that the content of the compound is 80.0 to 99.9 mass %:

(In the above formula (1), X is a divalent linking group selected from a direct bond, -SO ₂ -, -O-, -CO-, -C(CF ₃ ) ₂ -, -S-, and an aliphatic hydrocarbon group having 1 to 20 carbon atoms. ^{R 1} and R ² are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen atom, and may be the same or different.)

The propenyl group-containing composition of the present invention is defined as a "propenyl group-containing composition" because it contains a compound represented by the above formula (1) (hereinafter, sometimes referred to as "propenyl group-containing compound (1)") and other optional components (for example, a compound represented by formula (2) described below). However, in the technical field of the compound, a "propenyl group-containing compound" may be obtained as a "composition" consisting of multiple components other than a single component. Therefore, the propenyl group-containing composition of the present invention is sometimes expressed in the industry as a "propenyl group-containing compound" (sometimes referred to as a "propenyl group-containing resin") or sold as a "propenyl group-containing compound" (sometimes referred to as a "propenyl group-containing resin").

<Propenyl Group-Containing Compound (1)>
In the above formula (1) representing the propenyl group-containing compound (1), the aliphatic hydrocarbon group having 1 to 20 carbon atoms for X is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms, and particularly preferably an alkylene group which may have a branch and has 1 to 10 carbon atoms. X is preferably a direct bond or an aliphatic hydrocarbon group having 1 to 10 carbon atoms, more preferably a direct bond, a methylene group, or an isopropylidene group, and most preferably a direct bond.

Examples of the halogen atoms for R ¹ and R ² include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the hydrocarbon groups having 1 to 10 carbon atoms for R ¹ and R ² include alkyl groups having 1 to 10 carbon atoms. Preferably, R ¹ and R ² are each independently a hydrogen atom or a methyl group, and most preferably, R ¹ and R ² are both hydrogen atoms.

The propenyl group-containing compound (1) represented by formula (1) contains cis-trans isomers of the double bonds of the propenyl group (1-propenyl group) bonded to each of the two benzene rings, and includes a "trans isomer" in which both of the two propenyl groups in formula (1) are in the trans form, and a "cis isomer" in which both are in the cis form.

The proportion of trans isomers in the propenyl group-containing compound (1) is preferably 20 to 95%, more preferably 30 to 85%, and even more preferably 45 to 75%. The greater the proportion of trans isomers, the higher the crystallinity and the easier it is to handle in powder form. The smaller the proportion, the better the solubility in solvents.

The proportion of cis isomers in the propenyl group-containing compound (1) is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less. The smaller the proportion of cis isomers, the higher the crystallinity and the easier it is to handle the powder. There is no particular lower limit for the proportion of cis isomers, but from the viewpoint of melting properties when heated, it is preferably 1% or more.

Propenyl group-containing compound (1) also includes other propenyl group-containing compounds (1) that do not belong to either the trans or cis form. These are compounds in which one of the two propenyl groups in formula (1) is a trans type and the other is a cis type, and are usually contained in propenyl group-containing compound (1) at about 5 to 50%.

The ratio of the trans and cis forms of the propenyl group-containing compound (1) can be controlled, for example, by changing the type of solvent used in the propenylation reaction during the production of the propenyl group-containing compound (1).

The propenyl group-containing composition of the present invention contains 80.0 to 99.9% by mass of the propenyl group-containing compound (1). If the content of the propenyl group-containing compound (1) in the propenyl group-containing composition of the present invention is less than 80.0% by mass, the effects of high heat resistance, low viscosity, and long-term reliability due to the inclusion of the propenyl group-containing compound (1) cannot be fully obtained. Since it is practically difficult to produce a propenyl group-containing composition consisting of 100% by mass of the propenyl group-containing compound (1), the content of the propenyl group-containing compound (1) in the propenyl group-containing composition of the present invention is usually 99.9% by mass or less. In order to further enhance the effect of the propenyl group-containing compound (1) while also considering solubility in a solvent, the content of the propenyl group-containing compound (1) in the propenyl group-containing composition of the present invention is preferably 85.0 to 99.8% by mass, more preferably 90.0 to 99.5% by mass.

In the propenyl group-containing composition of the present invention, a propenyl group-containing compound (2) described below remains in the propenylation reaction for producing a propenyl group-containing compound (1). The contents of the propenyl group-containing compound (1) and the propenyl group-containing compound (2) described below can be controlled, for example, by changing the amount of the solvent in the propenylation reaction.
That is, in order to decrease the amount of propenyl group-containing compound (1) and increase the amount of propenyl group-containing compound (2), for example, the amount of solvent can be increased. Conversely, in order to increase the amount of propenyl group-containing compound (1) and decrease the amount of propenyl group-containing compound (2), for example, the amount of solvent can be decreased.

The propenyl group-containing composition of the present invention essentially consists of the propenyl group-containing compound (1) and the propenyl group-containing compound (2) described below. Although a trace amount of impurities may be contained during the production of the propenyl group-containing compound (1), the total content of the propenyl group-containing compound (1) and the propenyl group-containing compound (2) in the propenyl group-containing composition is preferably 70% by mass or more, particularly 80 to 100% by mass. Inevitable impurities during the production of the propenyl group-containing compound (1) can be reduced by purifying the resulting propenyl group-containing composition by washing with water, chromatographic separation, crystallization, etc.

<Propenyl Group-Containing Compound (2)>
The propenyl group-containing composition of the present invention preferably contains 0.1 to 20.0 mass % of a compound having a 2-propenyl group (allyl group) represented by the following formula (2) (hereinafter, may be referred to as "propenyl group-containing compound (2)").

(In the above formula (2), X, R ¹ and R ² are defined as in the above formula (1).)

The propenyl group-containing composition of the present invention tends to have a lower melt viscosity as the propenyl group-containing compound (2) is more present, and the curing time of a curable resin composition containing this propenyl group-containing composition tends to be longer as the propenyl group-containing compound (2) is less. From this viewpoint, the content of the propenyl group-containing compound (2) in the propenyl group-containing composition of the present invention is preferably 0.2 to 10.0% by mass, and more preferably 0.3 to 5.0% by mass.

<Melt Viscosity>
The propenyl group-containing composition of the present invention preferably has a melt viscosity at 150° C. of 0.01 to 10.0 P, more preferably 0.05 to 5 P, and even more preferably 0.1 to 3 P. If the melt viscosity is equal to or less than the upper limit, the composition is easily mixed with a maleimide resin, an epoxy resin, or the like, which will be described later, due to its low viscosity. If the melt viscosity is equal to or more than the lower limit, bleeding out is unlikely to occur when the composition is molded into a mold or the like.
The melt viscosity of the propenyl group-containing composition is measured by the method described in the Examples section below.

<Softening point>
The softening point of the propenyl group-containing composition of the present invention is preferably 30 to 100° C., more preferably 35 to 80° C., and even more preferably 40 to 70° C. If the softening point is equal to or higher than the above lower limit, blocking is unlikely to occur, whereas if the softening point is equal to or lower than the above upper limit, the composition will flow in a short time when heated.
The softening point of the propenyl group-containing composition is measured by the method described in the Examples section below.

<Production of Propenyl Group-Containing Composition>
The method for producing the propenyl group-containing composition of the present invention is not particularly limited, but examples thereof include a method in which a dihydric phenol compound represented by the following formula (3) (hereinafter sometimes abbreviated as "dihydric phenol compound (3)") is allylated to obtain an allyloxy group-containing compound represented by the following formula (4) (hereinafter sometimes abbreviated as "allyloxy group-containing compound (4)"), and then the allyl group of the allyloxy group-containing compound (4) is transferred to obtain the above-mentioned propenyl group-containing compound (2), and the allyl group of this propenyl group-containing compound (2) is converted to a 1-propenyl group to obtain the propenyl group-containing composition of the present invention.

(In the above formulas (3) and (4), X, R ¹ and R ² are defined as in the above formula (1).)

An example of a method for allylation of the dihydric phenol compound (3) is a method in which the dihydric phenol compound (3) is reacted with an allyl halide to convert at least a portion of the hydroxyl groups into an allylic ether, thereby converting them to —O—CH ₂ —CH═CH ₂ .

In this reaction, it is preferable to use 2.0 to 8.0 times, and particularly 3.0 to 6.0 times, the molar amount of the allyl halide relative to the dihydric phenol compound (3) in order to efficiently proceed with the reaction while reducing production costs.

The allyl etherification reaction between the dihydric phenol compound (3) and an allyl halide is preferably carried out in the presence of a catalyst.

Catalysts for the allyl etherification reaction include, for example, alkali metals such as sodium hydroxide, potassium hydroxide, and potassium carbonate, amines such as diazabicyclononene, diazabicycloundecene, triethylamine, sodium tert-butoxide, potassium tert-butoxide, lithium diisopropylamide, silicon-basic amines, and lithium tetramethylpiperidine. Among these, alkali metals, diazabicyclononene, and diazabicycloundecene are preferred because they are relatively inexpensive and less likely to cause side reactions. One type of catalyst may be used alone, or two or more types may be used in combination.

The amount of catalyst used in the allyl etherification reaction is preferably 0.7 to 2.0 times the molar amount of the allyl halide used, and more preferably 0.8 to 1.5 times the molar amount. If too little catalyst is used, the reaction rate will be slow, and if too much is used, the excess alkali will have to be removed, resulting in reduced productivity.

The allyl etherification reaction is preferably carried out in the presence of a solvent, and examples of the solvent for the allyl etherification reaction include the polar solvents used in the propenylation reaction described below.

The reaction temperature for the allyl etherification reaction is not particularly limited as long as it is a temperature at which the hydroxyl group of the dihydric phenol compound (3) reacts with the allyl halide, and is preferably 10 to 150°C, more preferably 40 to 130°C.

After the allyl etherification reaction, if necessary, the reaction product may be subjected to processes such as removal of unreacted raw materials by distillation, concentration, and purification (washing, column chromatography, etc.).

The transfer of the allyl group of the allyloxy group-containing compound (4) obtained by the allylation of the dihydric phenol compound (3) can be carried out, for example, by a Claisen rearrangement reaction by heating the allyloxy group-containing compound (4) after the allylation reaction. By the Claisen rearrangement reaction, the allyl group of the allyloxy group (-O-CH ₂ -CH═CH ₂ ) bonded to the benzene ring of the allyloxy group-containing compound (4) is rearranged to the ortho position of the position where the allyloxy group was previously present.

The Claisen rearrangement reaction may be carried out according to a conventional method, for example, by heating the allyloxy group-containing compound (4) in the presence of a high-boiling solvent such as carbitol, paraffin oil, N,N'-dimethylaniline, N,N'-diethylaniline, or the like, or in the absence of a solvent. The solvent is used as needed in an amount of 10 to 200 parts by mass per 100 parts by mass of the allyloxy group-containing compound (4). After the reaction is completed, the solvent used can be removed as needed to obtain the propenyl group-containing compound (2). After the reaction, the propenyl group-containing compound (2) can be recovered by dropping the reaction solution into an aqueous sodium hydroxide solution, dropping the separated aqueous layer into an acid solution, and stirring.

The heating temperature during this Claisen rearrangement reaction is preferably 150 to 220°C, more preferably 170 to 200°C, and even more preferably a rearrangement reaction in the presence of an inert gas such as nitrogen. If the heating temperature is equal to or higher than the lower limit, the rearrangement reaction of the allyl group is likely to occur. If the heating temperature is equal to or lower than the upper limit, polymerization of the allyl group is unlikely to occur.

After the reaction, the reaction product may be washed with water or other treatments as necessary.

The drop time into the sodium hydroxide aqueous solution after the reaction is preferably 10 to 30 minutes. If the drop time is equal to or greater than the lower limit above, heat generation due to mixing is suppressed and safe production can be achieved. If the drop time is equal to or less than the upper limit above, productivity is improved. The stirring time after dropwise addition into the acid solution is preferably 15 to 60 minutes. If the stirring time is equal to or greater than the lower limit above, the neutralization reaction proceeds and the yield in the subsequent separation process is improved. If the stirring time is equal to or less than the upper limit above, productivity is improved.

One method for converting the allyl group of the propenyl group-containing compound (2) to a 1-propenyl group is to dissolve the propenyl group-containing compound (2) in a solvent and heat it in the presence of a catalyst for the propenylation reaction.

The solvent used in the propenylation reaction may be any solvent capable of dissolving the propenyl group-containing compound (2), and typically includes polar solvents.
Examples of polar solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, N,N-dimethylformamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, methanol, ethanol, butanol, ethyl acetate, butyl acetate, methyl cellosolve, ethyl diglycol acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and tetrahydrofuran. As the solvent, one type may be used alone, or two or more types may be used in combination.

The solvent is preferably used in an amount of 20 to 900 parts by weight, and more preferably 50 to 600 parts by weight, per 100 parts by weight of the propenyl group-containing compound (2).

Catalysts for the propenylation reaction include, for example, alkali metals such as sodium hydroxide and potassium hydroxide, amines such as diazabicyclononene, diazabicycloundecene, triethylamine, sodium tert-butoxide, potassium tert-butoxide, lithium diisopropylamide, silicon-basic amines, lithium tetramethylpiperidine, etc. Among these, potassium hydroxide and sodium hydroxide are preferred because they are relatively inexpensive and less likely to cause side reactions. One type of catalyst may be used alone, or two or more types may be used in combination.

The amount of catalyst used in the propenylation reaction is preferably 0.4 to 6.0 times the total molar amount of hydroxyl groups in the propenyl group-containing compound (2), and more preferably 1.0 to 4.0 times the total molar amount. If the amount of catalyst used is too small, the propenylation reaction does not proceed smoothly, and if the amount used is too large, the excess alkali must be removed, resulting in reduced productivity.

The reaction temperature for the propenylation reaction is preferably 40 to 140°C, more preferably 70 to 120°C. If the reaction temperature is equal to or higher than the lower limit, the propenylation reaction proceeds easily. If the reaction temperature is equal to or lower than the upper limit, polymerization of the propenyl group is unlikely to occur.

After the propenylation reaction, the reaction product may be subjected to processes such as removal of unreacted raw materials by distillation, concentration, and purification (washing, column chromatography, etc.) as necessary.

In the present invention, the propenyl group-containing compound (1) after the propenylation reaction and the propenyl group-containing compound (2) may be blended to form the propenyl group-containing composition of the present invention.

[Curable resin composition]
The curable resin composition of the present invention is a resin composition comprising the propenyl group-containing composition of the present invention described above and a resin selected from the group consisting of epoxy resins, maleimide resins, phenolic resins, benzoxazine resins, cyanate ester resins, active ester resins, and resins having radical polymerizable functional groups. The curable composition includes one or more resins selected from the group consisting of a resin having a structure having a carboxylic acid group, an isocyanate resin, an acid anhydride resin, and a carbodiimide resin (hereinafter, these may be referred to as "curing components"). Preferably, the resin is one or more resins selected from the group consisting of epoxy resins, maleimide resins and phenol resins.

In the curable resin composition of the present invention, the 1-propenyl group or allyl group of the propenyl group-containing composition of the present invention reacts with the maleimide group of the maleimide resin under certain conditions, whereby curing proceeds. Thus, in the present invention, the propenyl group-containing composition functions as a curing agent for the maleimide resin.
In the case of epoxy resins, the curing reaction proceeds by reacting the hydroxyl groups of the propenyl group-containing composition of the present invention with the epoxy groups of the epoxy resin. In this case too, the propenyl group-containing composition functions as a curing agent for the epoxy resin.
The phenolic resin can also be used in combination with an epoxy resin.
The curable resin composition of the present invention preferably contains an epoxy resin as a curing component, particularly when used as a semiconductor encapsulant, because the cured product has excellent adhesion and the curing reaction is easily promoted to increase the molecular weight of the cured product.

In the curable resin composition of the present invention, the content of the curing component is 0.01 to 1000 parts by mass, preferably 0.1 to 500 parts by mass, and more preferably 1.0 to 300 parts by mass, per 100 parts by mass of the propenyl group-containing composition of the present invention. If the content of the curing component is equal to or greater than the above lower limit, a cured product with excellent heat resistance and good adhesion can be obtained. If the content of the curing component is equal to or less than the above upper limit, a uniform cured product with excellent curability can be produced.

<Curing component>
Each curing component contained in the curable resin composition of the present invention will be described below.

<Maleimide resin>
The maleimide resin is a maleimide compound having an average of one or more maleimide groups per molecule. Examples of the maleimide resin include bismaleimides having two maleimide groups per molecule, polyphenylmethanemaleimide, and the like.

Examples of bismaleimides include alkyl bismaleimide, diphenylmethane bismaleimide, phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 4,4'-diphenylmethane bismaleimide such as 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, and 1,3-bis(4-maleimidophenoxy)benzene.
Polyphenylmethanemaleimide is a polymer in which three or more benzene rings substituted with maleimide groups are bonded via methylene groups.

Of the maleimide resins mentioned above, 4,4'-diphenylmethane bismaleimide and polyphenylmethane maleimide are preferred because they have excellent compatibility with the propenyl group-containing composition of the present invention and are relatively inexpensive.

Commercially available maleimide resins may be used. Examples of commercially available maleimide resins include "BMI-1100" (4,4'-diphenylmethane bismaleimide) and "BMI-2300" (polyphenylmethane maleimide) manufactured by Daiwa Kasei Kogyo Co., Ltd.

One type of maleimide resin may be used alone, or two or more types may be used in combination.

<Epoxy resin>
The epoxy resin is not particularly limited, and examples thereof include phenol novolac type epoxy resins, orthocresol novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, biphenol type epoxy resins, naphthalene type epoxy resins, anthracene type epoxy resins, naphthol type epoxy resins, xylylene type epoxy resins, biphenyl type epoxy resins, triphenylmethane type epoxy resins, dicyclopentadiene type epoxy resins, stilbene type epoxy resins, sulfur atom-containing epoxy resins, and phosphorus atom-containing epoxy resins.

As the epoxy resin, an epoxy resin in which at least a portion of the hydroxyl groups of a propenyl group-containing composition have been epoxidized may be used. The hydroxyl groups can be epoxidized by a known method. For example, by reacting the propenyl group-containing composition with epichlorohydrin, an epoxy resin having a structure in which some or all of the hydroxyl groups of the propenyl group-containing composition have been converted to -OZ (where Z is a glycidyl group) can be obtained.

Epoxy resins may be used alone or in combination of two or more types.

<Phenol resin>
Examples of phenolic resins include novolak-type phenolic resins obtained by condensing or co-condensing phenols such as phenol, cresol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol, and/or naphthols such as α-naphthol, β-naphthol, and dihydroxynaphthalene, and compounds having an aldehyde group such as formaldehyde, benzaldehyde, and salicylaldehyde, under an acidic catalyst; phenol-aralkyl resins synthesized from phenols and/or naphthols and dimethoxyparaxylene or bis(methoxymethyl)biphenyl; biphenylene-type phenolic resins, such as phenol-aralkyl ... Examples of the phenolic resin include aralkyl-type phenolic resins such as phenol-aralkyl resins and naphthol-aralkyl resins; dicyclopentadiene-type phenolic resins such as dicyclopentadiene-type phenolic novolak resins and dicyclopentadiene-type naphthol novolak resins which are synthesized by copolymerizing phenols and/or naphthols with dicyclopentadiene; triphenylmethane-type phenolic resins; terpene-modified phenolic resins; paraxylylene- and/or metaxylylene-modified phenolic resins; melamine-modified phenolic resins; cyclopentadiene-modified phenolic resins; and phenolic resins obtained by copolymerizing two or more of these.

The phenolic resins may be used alone or in combination of two or more.

<Benzoxazine resin>
Examples of benzoxazine resins include 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine), 6,6-(1-methylethylidene)bis(3,4-dihydro-3-methyl-2H-1,3-benzoxazine), etc. The benzoxazine resin may contain a structure in which the oxazine ring is ring-opened and polymerized.
The benzoxazine resin may be used alone or in combination of two or more kinds.

<Cyanate ester resin>
Examples of the cyanate ester resin 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 are partially converted to triazine.

Cyanate ester resins may be used alone or in combination of two or more types.

<Active ester resin>
The active ester resin is not particularly limited, but generally, compounds having two or more highly reactive ester groups in one molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds, are preferably used. The active ester resin 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 resin obtained from a carboxylic acid compound and a hydroxy compound is preferred, and an active ester resin obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred.
Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic 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, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compound, phenol novolak, etc. Here, the term "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing one molecule of dicyclopentadiene with two molecules of phenol.

Specifically, active ester resins containing a dicyclopentadiene-type diphenol structure, active ester resins containing a naphthalene structure, active ester resins containing an acetylated product of phenol novolac, and active ester resins containing a benzoylated product of phenol novolac are preferred, and among these, active ester resins containing a naphthalene structure and active ester resins containing a dicyclopentadiene-type diphenol structure are more preferred. Here, the term "dicyclopentadiene-type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentalene-phenylene.

The active ester resin may be used alone or in combination of two or more types.

<Resin Having a Radically Polymerizable Functional Group>
Resins having radical polymerizable functional groups include resins having one or more ethylenically unsaturated groups having a carbon-carbon double bond in the molecule. The ethylenically unsaturated group is preferably one or more groups selected from the group consisting of an acrylic group, a methacrylic group, a styryl group, an olefin group, and a maleimide group. Preferred examples of the olefin group include an allyl group, a vinyl group, and a propenyl group. Thus, in a preferred embodiment, the radical polymerizable functional group is one or more selected from the group consisting of an acrylic group, a methacrylic group, a styryl group, an allyl group, a vinyl group, a propenyl group, and a maleimide group.
The resin having a radically polymerizable functional group may have one or more types of radically polymerizable functional groups.

One type of resin having a radically polymerizable functional group may be used alone, or two or more types may be used in combination.

<Isocyanate resin>
The isocyanate resin may be a resin having one or more isocyanate groups in the molecule. The isocyanate resin may preferably have two or more isocyanate groups in the molecule. Examples of the isocyanate resin include 4,4'-diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, tolylene diisocyanate, and hexamethylene diisocyanate.

The isocyanate resin may be used alone or in combination of two or more types.

<Acid anhydride resin>
Examples of the acid anhydride resin include resins having one or more acid anhydride groups in the molecule. Examples of the acid anhydride resin include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, and benzophenone tetracarboxylic dianhydride. Examples of the acid anhydride include polymeric acid anhydrides such as water, biphenyltetracarboxylic dianhydride, naphthalenetetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3'-4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and styrene-maleic acid resin in which styrene and maleic acid are copolymerized.

The acid anhydride resin may be used alone or in combination of two or more types.

<Carbodiimide resin>
The carbodiimide resin may be a resin having one or more carbodiimide groups (-N=C=N-) in the molecule. The carbodiimide resin preferably has two or more carbodiimide groups in the molecule. Specific examples of the carbodiimide resin include "V-03" and "V-07" manufactured by Nisshinbo Chemical Inc.

One type of carbodiimide resin may be used alone, or two or more types may be used in combination.

<Other Ingredients>
The curable resin composition of the present invention may contain one or more other components in addition to the propenyl group-containing composition of the present invention and the above-mentioned curing component, such as a curing accelerator, an inorganic filler, a solvent, a release agent, a surface treatment agent, a colorant, a thermoplastic polymer, an organic filler, a flame retardant, etc.

Examples of the curing accelerator include a curing accelerator that accelerates the curing reaction between the propenyl group-containing composition of the present invention and a maleimide resin (hereinafter also referred to as "curing accelerator (P)"), and a curing accelerator that accelerates the curing reaction between the propenyl group-containing composition of the present invention and an epoxy resin other than the curing accelerator (P) (hereinafter also referred to as "curing accelerator (Q)").

Examples of the curing accelerator (P) include imidazoles and organic peroxides. When the curable resin composition contains an epoxy resin, the curing reaction between the propenyl group-containing composition of the present invention and the epoxy resin is also accelerated by using an imidazole as the curing accelerator (P).

Examples of imidazoles include 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethylimidazole, 2,4-dimethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-vinyl-2-methylimidazole, 1-propyl-2-methylimidazole, 2-isopropylimidazole, 1-cyanomethyl-2-methyl-imidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, and 1-cyanoethyl-2-phenylimidazole.

Examples of organic peroxides include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, and peroxyesters.

The curing accelerator (P) is preferably one that is relatively stable at high temperatures, has good solvent solubility, and is easy to handle. Among imidazoles, 2-ethyl-4-methylimidazole is preferred, and among organic peroxides, dicumyl peroxide, a dialkyl peroxide, is preferred.

These curing accelerators (P) may be used alone or in combination of two or more.

When the curable resin composition of the present invention contains a curing accelerator (P), the content thereof is preferably 0.1 to 5.0% by mass relative to the maleimide resin.

The curing accelerator (Q) is not particularly limited, and examples thereof include phosphorus compounds, tertiary amines, organic acid metal salts, Lewis acids, and amine complex salts.

Examples of the phosphorus-based compounds include triphenylphosphine, tris-2,6-dimethoxyphenylphosphine, tri-p-tolylphosphine, and triphenyl phosphite.
Examples of the tertiary amine include 2-dimethylaminomethylphenol, benzyldimethylamine, α-methylbenzyldimethylamine, and 1,8-diazabicyclo[5.4.0]undecene-7.

As the curing accelerator (Q), phosphorus-based compounds, especially triphenylphosphine, are preferred because they have better curability, heat resistance, and electrical properties, and are less likely to deteriorate in moisture resistance reliability.

These curing accelerators (Q) may be used alone or in combination of two or more.

When the curable resin composition of the present invention contains a curing accelerator (Q), the content thereof is preferably 0.1 to 5 mass% relative to the epoxy resin.

Examples of inorganic fillers include crystalline silica powder, fusible silica powder, quartz glass powder, talc, calcium silicate powder, zirconium silicate powder, alumina powder, calcium carbonate powder, etc. Of these, crystalline silica powder and fusible silica powder are preferred. One type of inorganic filler may be used alone, or two or more types may be used in combination.

When the curable resin composition of the present invention contains an inorganic filler, the content thereof is preferably 30 to 90 mass % based on the total curable resin composition.

When the curable resin composition of the present invention is used as a thermosetting molding material for forming an encapsulant, it is preferable that the curable resin composition of the present invention contains a curing accelerator and an inorganic filler.

The curable resin composition of the present invention can be made into a resin varnish by blending a solvent and dissolving the curing components such as maleimide resin and epoxy resin in the solvent. There are no particular limitations on the solvent as long as it dissolves the propenyl group-containing composition, the curing components, etc., and typically, a polar solvent is used. Examples of polar solvents include the same ones as those listed in the explanation of the propenylation reaction. The solvent may be used alone or in combination of two or more types.

The resin varnish contains the propenyl group-containing composition of the present invention, a curing component such as a maleimide resin or an epoxy resin, and a solvent as essential components, and can be used to manufacture laminates such as copper-clad laminates, as described below.

The content of the solvent in the resin varnish is appropriately set according to the solid content of the resin varnish, which varies depending on the application, but is preferably 30 to 80 mass %, more preferably 40 to 70 mass %.
The solid content concentration of the resin varnish is the ratio of the mass of the resin varnish excluding the solvent to the total mass of the resin varnish.

The resin varnish can be produced by mixing a curing component such as a maleimide resin or an epoxy resin, the propenyl group-containing composition of the present invention, and other components and a solvent that are blended as necessary. The components can be mixed by a conventional method.

In producing a resin varnish, a curing component such as a maleimide resin, the propenyl group-containing composition of the present invention, and a solvent may be mixed, and then the maleimide resin or the like may be pre-reacted with the propenyl group-containing composition of the present invention. By carrying out the pre-reaction in the varnish state, it is possible to prevent the precipitation of the highly crystalline maleimide resin or the like from the resin varnish.

The reaction temperature during the pre-reaction is preferably 50 to 150°C, more preferably 70 to 130°C, and even more preferably 80 to 120°C. If the reaction temperature is too low, the reaction will not proceed smoothly. If the reaction temperature is too high, it will be difficult to control the reaction, and it will be difficult to stably obtain a resin varnish.

Examples of the release agent include various waxes such as carnauba wax.
The surface treatment agent may be a known silane coupling agent.
The colorant may be carbon black or the like.

Thermoplastic polymers include polyethylene, polypropylene, polystyrene, polyphenylene ether resin, phenoxy resin, polycarbonate resin, polyester resin, polyamide resin, polyamideimide resin, polyimide resin, xylene resin, polyphenylene sulfide resin, polyetherimide resin, polyetheretherketone resin, polyetherimide resin, silicone resin, tetrafluoroethylene resin, etc.

Examples of organic fillers include resin fillers with a uniform structure made of polyethylene, polypropylene, polystyrene, polyphenylene ether resin, silicone resin, tetrafluoroethylene resin, etc., and resin fillers with a core-shell structure having a rubber-like core layer made of acrylic acid ester resin, methacrylic acid ester resin, conjugated diene resin, etc., and a glassy shell layer made of acrylic acid ester resin, methacrylic acid ester resin, aromatic vinyl resin, vinyl cyanide resin, etc.

Examples of flame retardants include halogen-containing flame retardants containing bromine or chlorine; phosphorus-based flame retardants such as triphenyl phosphate, tricresyl phosphate, tris-dichloropropyl phosphate, phosphate ester compounds, and red phosphorus; nitrogen-based flame retardants such as guanidine sulfamate, melamine sulfate, melamine polyphosphate, and melamine cyanurate; phosphazene-based flame retardants such as cyclophosphazene and polyphosphazene; and inorganic flame retardants such as antimony trioxide.

The curable resin composition of the present invention is preferably cured by controlling the curing temperature to 150 to 250°C. One example of the curing operation is a method in which the composition is first cured at the suitable curing temperature for 30 seconds to 3 hours, and then post-cured at the suitable curing temperature for 1 to 20 hours.

The propenyl group contained in the curable resin composition of the present invention, i.e., the propenyl group possessed by the propenyl group-containing compound (1) in the propenyl group-containing composition of the present invention, reacts more easily with the maleimide group contained in the maleimide resin than the allyl group. Therefore, the curable resin composition of the present invention has a high curing rate and excellent curability. In addition, since the curable resin composition of the present invention has a high curing rate, it is not necessary to use a curing accelerator such as an organic peroxide, which requires careful handling. By not incorporating a curing accelerator into the curable resin composition of the present invention, the handling property is improved.

The hydroxyl group contained in the curable resin composition of the present invention, i.e., the hydroxyl group of the propenyl group-containing compound (1) in the propenyl group-containing composition of the present invention, reacts with the epoxy group of the epoxy resin. The reaction rate of the reaction between the hydroxyl group and the epoxy group can be accelerated by the presence of a curing accelerator such as triphenylphosphine. When cured with the epoxy resin, the propenyl group of the propenyl group-containing compound (1) undergoes a self-polymerization reaction, and the crosslinked structure formed by the self-polymerization has hydrophobicity and flexibility, so that the water absorption of the cured product is reduced and the adhesive strength is improved.

The curable resin composition containing maleimide resin is usually cured by heating at a high temperature of 80 to 250°C. In conventional curable resin compositions, some of the resin components volatilize during curing, resulting in voids in the cured product. However, the curable resin composition of the present invention uses the propenyl group-containing composition of the present invention, and the curing reaction is fast, so volatilization is less likely to occur during curing. Therefore, voids are less likely to occur in the cured product, and the defective rate in the manufacture of electronic components and the like is reduced, resulting in higher productivity. In addition, the use of the propenyl group-containing composition of the present invention creates a highly hydrophobic crosslinked structure, which reduces the water absorption of the cured product, and electronic components and the like using the cured product are less likely to crack even when exposed to high temperatures.

In the curable resin composition of the present invention containing the propenyl group-containing composition of the present invention, the density per unit weight of the propenyl groups in the propenyl group-containing compound (1) is high, and the crosslinked structure upon curing has a high density, so that the cured product has excellent heat resistance.
In this way, by using the curable resin composition of the present invention, a cured product having excellent heat resistance and low water absorption can be formed in a short time while suppressing the occurrence of voids, and laminates, sealing materials, etc. can be produced with high productivity.

The uses of the curable resin composition of the present invention will be described further below, but examples include sealing materials for electronic components such as semiconductors, electrical insulating materials, resins for copper-clad laminates, resists, resins for liquid crystal color filters, various coating agents, adhesives, build-up laminate materials, fiber-reinforced plastics (FRP), etc.

The curable resin composition of the present invention may be used for these applications after curing, or may be cured during the manufacturing process for these applications.

[Cured product]
The cured product of the present invention can be obtained by curing the curable resin composition of the present invention. The cured product of the present invention obtained by curing the curable resin composition of the present invention has excellent properties in curability, crack resistance, heat resistance, low water absorption, adhesion, low linear expansion, moldability, and strength.

The method for curing the curable resin composition of the present invention is not particularly limited, but a cured product can usually be obtained by a thermosetting reaction by heating. During the thermosetting reaction, it is preferable to appropriately select the curing temperature depending on the type of curing component used. For example, when a maleimide resin is used, the curing temperature is usually 80 to 250°C, and for an epoxy resin, it is usually 100 to 200°C. It is also possible to lower the curing temperature by adding a curing accelerator to these curing components. The curing reaction time is preferably 1 to 20 hours, more preferably 2 to 18 hours, and even more preferably 3 to 15 hours. If the reaction time is equal to or greater than the lower limit, the curing reaction tends to proceed sufficiently, which is preferable. On the other hand, if the reaction time is equal to or less than the upper limit, it is preferable because it is easier to reduce deterioration due to heating and energy loss during heating.

[Application]
The curable resin composition of the present invention has excellent curability, and a cured product using the curable resin composition of the present invention has excellent crack resistance, heat resistance, low water absorbency, adhesion, toughness, low linear expansion and moldability.

Therefore, the propenyl group-containing composition, curable resin composition and cured product thereof of the present invention can be effectively used in any application where these physical properties are required. For example, they can be suitably used in the fields of coatings such as optical materials, automotive paints such as electrocoating paints for automobiles, heavy-duty anticorrosive paints for ships and bridges, and paints for coating the inside of beverage cans; in the fields of electrical and electronics such as composite materials, laminates, semiconductor sealants, liquid insulating sealants, insulating powder paints, and coil impregnation; in the fields of civil engineering, construction and adhesives such as earthquake-resistant reinforcement of bridges, concrete reinforcement, flooring materials for buildings, linings for water facilities, drainage and permeable pavements, and adhesives for structures, vehicles and aircraft. Among these, they are particularly useful for electrical and electronic parts.

[Laminate]
An example of a method for producing a laminate using the curable resin composition of the present invention is a method in which a laminate including a prepreg having a fibrous substrate impregnated with the resin varnish comprising the curable resin composition of the present invention is heated and pressurized to produce a laminate.

More specifically, a fibrous substrate is impregnated with a resin varnish, dried, and the solvent is removed to produce a prepreg. This prepreg is then laminated with other substrates as required to form a laminate, which is then heated and pressurized to harden it, producing a laminate.

The number of layers of prepreg in the laminate may be one or two or more. In the laminate, a substrate other than the prepreg may be laminated. Examples of the substrate include a metal foil such as copper foil.

Examples of fibers constituting the fibrous substrate include inorganic fibers such as glass fibers, carbon fibers, ceramic fibers, and stainless steel fibers; natural fibers such as cotton, hemp, and paper; and synthetic organic fibers such as polyester resins and polyamide resins. Any one of these fibers may be used alone, or two or more types may be used in combination.

The shape of the fibrous substrate is not particularly limited, and examples include staple fibers, yarns, mats, sheets, etc.

The amount of resin varnish to be impregnated into the fibrous base material is not particularly limited, and for example, the solid content of the resin varnish to be impregnated is set to about 30 to 50 mass % relative to the fibrous base material (100 mass %).
The heating temperature when the laminate is heated and pressed is preferably the above-mentioned curing temperature. The pressing condition is preferably 2 to 20 kN/ ^m2 .

The laminate produced in this manner has a fiber-reinforced resin layer that includes a fibrous base material and a cured product of a resin varnish. The number of fiber-reinforced resin layers in the laminate may be one layer or two or more layers. As mentioned above, the laminate may have a metal foil layer such as copper foil.

[Sealing material]
When the curable resin composition of the present invention is used as an encapsulant, the shape of the encapsulant to which the curable resin composition of the present invention is applied is not particularly limited, and for example, a shape similar to that used in known semiconductors, etc. can be adopted.
Examples of a method for forming an encapsulant using the curable resin composition of the present invention include methods for encapsulating a semiconductor using transfer molding, compression molding, or the like.

The present invention will be explained in more detail below using examples, but the present invention is not limited to the following examples as long as it does not exceed the gist of the invention. The values of various manufacturing conditions and evaluation results in the following examples are meant as preferred upper or lower limit values in the embodiments of the present invention, and the preferred range may be a range defined by a combination of the above-mentioned upper or lower limit values and the values of the following examples or values between the examples.

[Materials used]
The compounds and resins used in the following examples and comparative examples are as follows.

- Other propenyl resins: Propylene derivatives of phenol biphenylene resins represented by the following structural formula ("BPN-01S" manufactured by Gun-ei Chemical Industry Co., Ltd.)

Maleimide resin: Polyphenylmethanemaleimide represented by the following structural formula ("BMI-2300" manufactured by Daiwa Kasei Kogyo Co., Ltd.)

Phenol resin: Phenol novolac represented by the following structural formula (Gun-ei Chemical Industry Co., Ltd. "PSM4261")

Epoxy resin: Tetramethylbiphenyl type epoxy resin represented by the following structural formula ("YX4000" manufactured by Mitsubishi Chemical Corporation)

Cure accelerator: Triphenylphosphine

[Example 1: Preparation of propenyl group-containing composition]
<Allylation>
In a 10L autoclave, 840mL of N,N-dimethylformamide, 575g (7.51mol) of allyl chloride, 1245g (9.01mol) of potassium carbonate, and 280g (1.50mol) of biphenol were added and sealed, and the mixture was heated to 40°C, and then heated to 65°C over 1 hour. After aging at 65°C for 5 hours, the mixture was cooled to room temperature and the autoclave was opened. 1678g of water and 1600g of methyl isobutyl ketone were added to the mixture to dissolve inorganic salts and crystals, and the water layer was removed by a separation operation. The remaining methyl isobutyl ketone layer was added with 1678g of water and washed with water at 60°C three times, and then methyl isobutyl ketone was distilled off to obtain a compound represented by the following formula (A) (hereinafter referred to as "compound (A)").

<Claisen rearrangement reaction>
Compound (A) 165g (620mmol) and N,N-diethylaniline 825mL were placed in a 2L four-neck flask, heated at 200°C for 6 hours, and then cooled to room temperature. Next, 495mL of water and 149mL (1.86mol) of 50% by mass aqueous sodium hydroxide solution were placed in a 2L separable flask and cooled to 10°C, and the N,N-diethylaniline solution was added dropwise, stirred for 30 minutes, and then allowed to stand, and the upper and lower layers were extracted. Next, 495mL of water and 93.1g (1.86mol) of concentrated sulfuric acid were placed in a 2L separable flask and cooled to 10°C, and the lower layer extracted in the previous operation was added dropwise and stirred for 1 hour. The precipitated solid was collected by filtration, washed with water, and then dried under reduced pressure to obtain 148 g (1.19 mol, two-stage yield 80.4%) of a compound represented by the following formula (2-1), which is a propenyl group-containing compound (2), as a gray solid (hereinafter referred to as "compound (2-1)").

<Propenylation>
100 parts by mass of compound (2-1) and 100 parts by mass of methanol were charged into a reaction vessel, stirred and dissolved, and then 79 parts by mass of granular potassium hydroxide (purity 85%) was added. After the addition, methanol was distilled off while heating, and the reaction was carried out for 4 hours while maintaining the internal temperature at 100°C. Then, 203 parts by mass of methyl isobutyl ketone was added, neutralized with sulfuric acid, and repeatedly washed with water. Next, methyl isobutyl ketone was distilled off from the oil layer under heating and reduced pressure at 120°C, thereby obtaining 95 parts by mass of a propenyl group-containing composition containing a compound having a structure represented by the following formula (1-1), which is a propenyl group-containing compound (1) (hereinafter referred to as "compound (1-1)").

As is clear from the composition analysis below, this propenyl group-containing composition contains compound (1-1) and a compound represented by the following formula (2-1) (hereinafter referred to as "compound (2-1)").

The resulting propenyl group-containing composition was subjected to composition analysis by the following method. The melt viscosity and softening point were also measured by the following method. The results are shown in Table 1.

<Composition Analysis of Propenyl Group-Containing Composition>
The propenyl group-containing composition was dissolved in acetone to a concentration of 1% by mass, and analyzed by liquid chromatography under the following conditions.
Apparatus: Agilent 1100 series Column: Imtakt Unison UK-C18
(4.6mm I.D. x 25cmL x 3μm)
Column tank temperature: 40°C
UV detection wavelength: 280 nm
Mobile phase conditions: pure water/methanol = 25/75

<Measurement of Melt Viscosity of Propenyl Group-Containing Composition>
The propenyl group-containing composition was melted on the hot plate of a cone-plate viscometer (manufactured by Tokai Yagami Co., Ltd.) adjusted to 150° C., and the melt viscosity was measured at a rotation speed of 750 rpm.

<Measurement of Softening Point of Propenyl Group-Containing Composition>
The softening point of the propenyl group-containing composition was measured in accordance with JIS K7234.

[Example 2: Preparation of propenyl group-containing composition]
The same procedure as in Example 1 was repeated, except that the sulfuric acid used for neutralization in the <propenylation> was changed to hydrochloric acid. The results are shown in Table 1.

[Example 3: Preparation of propenyl group-containing composition]
The same procedure as in Example 1 was repeated, except that the 100 parts by mass of methanol used in <Propenylation> was replaced by 900 parts by mass of dimethyl sulfoxide, and the 79 parts by mass of potassium hydroxide was replaced by 337 parts by mass of potassium t-butoxide. The results are shown in Table 1.

Comparative Example 1: Preparation of a propenyl group-containing composition
The same procedure as in Example 1 was repeated, except that the temperature during heating and reducing pressure in the <propenylation> step was 150° C. The results are shown in Table 1.

[Example 4: Preparation of propenyl group-containing composition]
The same procedure was carried out as in Example 1, except that in the propenylation, 100 parts by mass of compound (2-1) was replaced with 100 parts by mass of compound (2-2) (DABPA, manufactured by Daiwa Chemical Industry Co., Ltd.). The results are shown in Table 2.
As is clear from the composition analysis described below, the propenyl group-containing composition obtained in Example 4 contains a compound represented by the following formula (1-2) (hereinafter referred to as "compound (1-2)") and a compound represented by the following formula (2-2) (hereinafter referred to as "compound (2-2)").

[Example 5]
The propenyl group-containing composition produced in Example 1 and a maleimide resin were mixed in the ratio shown in Table 3 to obtain a curable resin composition, and then a curing reaction was carried out at 120°C for 2 hours and then at 200°C for 6 hours to produce a cured product.
The Tg (tan δ) and storage modulus E' (250°C) and E' (40°C) of the obtained cured product were measured by the methods described below. In addition, the shear adhesive strength to metal (Cu) was measured using the produced curable resin composition. The results are shown in Table 3.

[Example 6]
The propenyl group-containing composition produced in Example 4 and a maleimide resin were mixed in the ratio shown in Table 3 to obtain a curable resin composition, and then a curing reaction was carried out at 120°C for 2 hours and then at 200°C for 6 hours to produce a cured product.
The Tg (tan δ) and storage modulus E' (250°C) and E' (40°C) of the obtained cured product were measured by the methods described below. In addition, the shear adhesive strength to metal (Cu) was measured using the produced curable resin composition. The results are shown in Table 3.

[Comparative Example 2]
Other propenyl resins and maleimide resins were mixed in the ratios shown in Table 3 to obtain curable resin compositions, which were then cured at 120°C for 2 hours and then at 200°C for 6 hours to produce cured products.
The Tg (tan δ) and storage modulus E' (250°C) and E' (40°C) of the obtained cured product were measured by the methods described below. In addition, the shear adhesive strength to metal (Cu) was measured using the produced curable resin composition. The results are shown in Table 3.

<Cured product: Tg (tan δ) and storage modulus E' (250°C), E'(40°C)>
The cured product was cut into a test piece of 5 cm length, 1 cm width, and 4 mm thickness, and the dynamic viscoelasticity measurement (DMA) was performed under the following conditions.
The Tg (tan δ) and the storage modulus (E′) at 250° C. and 40° C. were measured.
Analytical equipment: Seiko Instruments EXSTAR6100
Measurement mode: 3-point bending mode Measurement temperature range: 30°C to 280°C
Heating rate: 5° C./min
Cooling rate: 5℃/min
*The temperature at the peak top of tan δ was taken as Tg (tan δ).

<Shear adhesive strength to metal>
The test was carried out in accordance with JIS-K6850. That is, the curable resin composition was applied between two metal pieces (copper plates (double-sided sandblasted plates manufactured by Yutaka Panel Services)) with a width of 25 mm, a length of 100 mm, and a thickness of 1.6 mm, to a width of 25 mm and a length of 12.5 mm. After application, the composition was placed in a thermostatic chamber and cured at 120° C. for 2 hours and at 175° C. for 6 hours to prepare a peel test piece.
The prepared peel test pieces were subjected to a tensile shear test at a speed of 5 mm/min (n=3) using a tensile tester "Instron 5582" (manufactured by Instron Corporation), and the tensile shear strength was measured and the average value was calculated.

[Example 7, Comparative Examples 3 and 4]
The propenyl group-containing composition produced in Example 1, other propenyl resins, or phenolic resins were mixed with epoxy resins and curing accelerators in the formulations shown in Table 4 to obtain curable resin compositions, and then the curing reaction was carried out at 120°C for 2 hours and then at 200°C for 6 hours to produce cured products. The storage modulus E' (250°C) of the obtained cured products was measured by the method shown above. In addition, the shear adhesive strength to metal (aluminum) was measured in the same manner as above using the obtained curable resin composition, using an aluminum plate (double-sided sandblasted plate manufactured by Yutaka Panel Service Co., Ltd.) instead of a copper plate (double-sided sandblasted plate manufactured by Yutaka Panel Service Co., Ltd.). Furthermore, a water absorption test was carried out on the obtained cured products by the method shown below.
The results are shown in Table 4.
In Comparative Example 3, the cured product was brittle in the tests for E' (250°C) and water absorption, and the viscosity was too high to prepare test pieces for the test of shear adhesive strength, so evaluation was not possible.

<Water absorption test>
The cured product was cut into a size of 2 cm length, 2 cm width and 4 mm thickness to prepare a test piece, which was then left in a thermo-hygrostat (Nagano Science Co., Ltd., "LH21-11P") under an atmosphere of 85°C/85% RH for 168 hours, after which the water absorption rate of the cured product was calculated from the mass of the test piece before and after water absorption using the following formula.
Water absorption rate (%)={(mass of test piece after water supply−mass of test piece before water supply)/(mass of test piece before water supply)}×100

[Example 8, Comparative Example 5]
The propenyl group-containing composition produced in Example 1 or the compound (2-1), a maleimide resin, an epoxy resin, and a curing accelerator were mixed in the formulation shown in Table 5 to obtain a curable resin composition, and then a curing reaction was carried out at 200°C for 6 hours to produce a cured product.
The storage modulus E' (40°C), storage modulus E' (250°C) and Tg (tan δ) of the obtained cured product were measured by the methods described above. The linear expansion coefficient and weight loss at 200°C were also evaluated by the methods described below.
In addition, the obtained curable resin composition was used to measure the shear adhesive strength to metals (copper and aluminum) in the same manner as described above using a copper plate (double-sided sandblasted plate manufactured by Yutaka Panel Service Co., Ltd.) and an aluminum plate (double-sided sandblasted plate manufactured by Yutaka Panel Service Co., Ltd.), and the shear adhesive strength was evaluated according to the following criteria.
◯: shear adhesive strength of 8.0 MPa or more ×: shear adhesive strength of less than 8.0 MPa Furthermore, gel time evaluation was carried out by the method shown below.
The results are shown in Table 5.
In Comparative Example 5, the cured product was brittle in the tests for storage modulus E' (40° C.), storage modulus E' (250° C.) and Tg (tan δ), and test pieces could not be prepared and evaluation could not be performed.

<Evaluation of Linear Expansion Coefficient>
The cured product was cut into a cylindrical test piece with a diameter of about 7 mm and a thickness of 4 mm, and a thermomechanical analysis was performed in compression mode using a thermomechanical analyzer (TMA: EXSTAR6000 manufactured by Seiko Instruments Inc.) (measurement load: 30 mN, heating rate: 5° C./min twice, measurement temperature range: 30° C. to 3000° C.). From the results of the second measurement, the linear expansion coefficient in the temperature range shown in Table 5 was calculated.

<Evaluation of weight loss at 200°C>
The cured product was cut into a rectangular parallelepiped test piece measuring 4 cm in length, 2 cm in width and 4 mm in thickness, and placed in a heating furnace (Perfect Oven: SPHH-202 manufactured by ESPEC Corp.) and stored isothermally at 200° C. The weight change rate was calculated from the weight of the cured product before heating and the weight of the cured product at the test time shown in Table 5.
Weight change rate (%)=-{(mass of test piece after weight change-mass of test piece before weight change)/(mass of test piece before weight change)}×100

<Gel time evaluation>
0.1 g of the curable resin composition was placed on a gel time tester (BIG HEART, manufactured by Imoto Manufacturing Co., Ltd.) heated to 175° C., and the time until gelation proceeded (gel time) was measured. The time until gelation proceeded was defined as the time until the curable resin composition lost its fluidity as a liquid at 175° C.

[Evaluation of Results]
From Table 3, it can be seen that the cured products of Examples 5 and 6, which used the propenyl group-containing composition of Example 1, have superior heat resistance, show smaller changes in elastic modulus, and exhibit high adhesion to metals compared to the cured product of Comparative Example 2, which used another propenyl resin.
From Table 4, it can be seen that the cured product of Example 7, which used the propenyl group-containing composition of Example 1, exhibits a lower elastic modulus at high temperatures, lower moisture absorption, and higher adhesion compared to the cured products of Comparative Examples 3 and 4, which used other propenyl resins or phenolic resins.
From Table 5, it can be seen that the cured product of Example 8, which used the propenyl group-containing composition of Example 1, has a smaller linear expansion coefficient, higher strength, adhesive strength, and thermal decomposition resistance, and also has a shorter gel time and excellent moldability, compared to the cured product of Comparative Example 5, which used compound (2-1).

Claims (8)

A propenyl group-containing composition comprising a compound represented by the following formula (1), wherein the content of the compound represented by the formula (1) is 80.0 to 99.9 mass %:

(In the above formula (1), X is a direct bond . ^{R 1} and R ² are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen atom, and may be the same or different.) The propenyl group-containing composition according to claim 1, comprising 0.1 to 20.0 mass% of a compound represented by the following formula (2):

(In the above formula (2), X, R ¹ and R ² are defined as in the above formula (1).) The propenyl group-containing composition according to claim 1 or 2, wherein the proportion of trans isomers in which both of the propenyl groups are trans-types among the compounds represented by formula (1) is 20 to 95%. The propenyl group-containing composition according to any one of claims 1 to 3, wherein the proportion of cis isomers in which both of the propenyl groups are cis-types among the compounds represented by formula (1) is 30% or less. The propenyl group-containing composition according to any one of claims 1 to 4, having a melt viscosity at 150°C in the range of 0.01 to 10.0 P. A curable resin composition comprising 0.01 to 1000 parts by mass of at least one selected from the group consisting of epoxy resins, maleimide resins, phenolic resins, benzoxazine resins, cyanate ester resins, active ester resins, resins having radically polymerizable functional groups, isocyanate resins, acid anhydride resins, and carbodiimide resins, per 100 parts by mass of the propenyl group-containing composition according to any one of claims 1 to 5. A cured product obtained by curing the curable resin composition according to claim 6. Electrical/electronic parts containing a cured product of the curable resin composition according to claim 6.