JP7780354B2 - Compound, curable resin composition and cured product thereof - Google Patents

Description

The present invention relates to 2-pyrone-4,6-dicarboxylic acid (PDC) derivatives and methods for producing the same.

In recent years, attention has been focused on plant-derived polymers obtained from plant-derived raw materials or through microbial metabolism. These polymers are environmentally friendly materials that do not use petroleum as a raw material, and even when incinerated, they do not increase atmospheric carbon dioxide, in the sense that they return the carbon dioxide fixed in plants to the atmosphere. Furthermore, even if they are disposed of in a landfill rather than incinerated, they are decomposed by microorganisms in the soil, so there is no risk of environmental damage. Examples of such plant-derived polymers include polylactic acid and polyhydroxybutyric acid, and as promising biodegradable, environmentally friendly materials, their use in various molded products is being developed.

On the other hand, lignin, a plant-derived aromatic polymer compound, is a biomass resource that is ubiquitously found in plant cell walls. However, because its chemical structure is made up of a variety of components and its polymer structure is complex, no effective utilization technology has yet been developed. For example, lignin, which is produced in large quantities as a by-product in the papermaking industry, is not effectively utilized, but is instead incinerated as an alternative fuel to heavy oil.

In recent years, methods have been developed for producing the single compound 2-pyrone-4,6-dicarboxylic acid by converting plant-derived aromatic components such as lignin into a mixture of several low-molecular-weight compounds using chemical decomposition methods such as hydrolysis, oxidative decomposition, and solvolysis, or physicochemical decomposition methods using supercritical water or supercritical organic solvents. For example, Patent Document 1 discloses a method for producing the single compound 2-pyrone-4,6-dicarboxylic acid using fermentation production technology from a low-molecular-weight mixture containing vanillin, syringaldehyde, vanillic acid, syringic acid, protocatechuic acid, etc., obtained by using a low-molecular-weight decomposition technology to decompose plant materials containing lignin, through a multi-step enzymatic reaction.

If the single compound obtained in this way, 2-pyrone-4,6-dicarboxylic acid, could be used as a raw material for biodegradable plastics and various chemical products, it would enable the effective use of lignin-containing plant materials (biomass), which do not compete with food in supply. However, little is known about how to utilize 2-pyrone-4,6-dicarboxylic acid derived from lignin-containing biomass.

Patent No. 6674283

Patent Document 1 reports an epoxy resin composition that uses 2-pyrone-4,6-dicarboxylic acid as an epoxy resin curing agent. However, 2-pyrone-4,6-dicarboxylic acid is a solid with poor solubility, which makes it difficult to work with when blended with epoxy resin. Furthermore, the compounds have poor compatibility and are difficult to mix, making it impossible to create a uniform cured film and making it difficult to achieve the inherent cured physical properties of the resin. Therefore, there is a need for a new 2-pyrone-4,6-dicarboxylic acid derivative that has good solubility and compatibility with resins, is liquid, and offers excellent workability when blended with epoxy resins.

The present invention was made in consideration of the above-mentioned problems, and aims to provide a 2-pyrone-4,6-dicarboxylic acid derivative that is liquid, has excellent workability when blended with epoxy resins, and also has excellent cured physical properties, as well as a curable resin composition containing the same.

That is, the present invention relates to the following (1) to (8): In the present invention, "(Numerical value 1) to (Numerical value 2)" indicates that the upper and lower limit values are included.
(1) A compound represented by the following formula (a-1):

(In formula (a-1), R ₁ and R ₂ each represent an organic group containing a carboxy group and having 1 to 15 carbon atoms. n represents the number of repetitions and is an integer of 1 to 4.)
(2) The compound according to the preceding item (1), wherein R ₁ and R ₂ in formula (a-1) are each one selected from the following formulas (2a) to (2c), (3a) to (3i), or (4a) to (4d):

(The * symbol indicates that the group is bonded to the oxygen atom in formula (a-1).)
(3) The compound according to the above (1) or (2), wherein n in the formula (a-1) is 1.
(4) A mixture containing the compound according to any one of (1) to (3) above and a carboxylic acid anhydride compound.
(5) A curable resin composition containing the compound according to any one of (1) to (3) above or the mixture according to (4) above.
(6) A curable resin composition according to the above (5), further comprising an epoxy resin.
(7) The curable resin composition according to the above (5) or (6), further comprising a curing agent.
(8) The curable resin composition according to any one of (5) to (7) above, which is a semiconductor encapsulant.

The compound of the present invention is liquid and has good compatibility with epoxy resins, making it not only easy to work with, but also suitable for use in materials that require heat resistance (Tg) and low water absorption, particularly as a semiconductor encapsulant.

^{The 1} H-NMR charts of compounds 1 and 2 are shown below.

The present invention will be described in detail below.
The compound of the present invention is represented by the following formula (a-1).

(In formula (a-1), R ₁ and R ₂ each represent an organic group containing a carboxy group and having 1 to 15 carbon atoms. n represents the number of repetitions and is an integer of 1 to 4.)

In formula (a-1), n is preferably 1 or 2, and particularly preferably 1.

In the formula (a-1), R ₁ and R ₂ may be the same or different, but it is more preferable that they are the same.

Specific examples of R ₁ and R ₂ in formula (a-1) include organic groups having an aromatic ring represented by the following formulas (2a) to (2c), organic groups having an alicyclic ring represented by the following formulas (3a) to (3i), and organic groups having an alicyclic ring represented by the following formulas (4a) to (4d). Among these, organic groups represented by the following formulas (3a) to (3e) are preferred.

(The * symbol indicates a bond to the oxygen atom in formula (a-1).)

The compound represented by formula (a-1) can be obtained by an addition reaction between an alcohol represented by formula (a) below and a carboxylic acid anhydride compound (hereinafter simply referred to as an acid anhydride):

(In formula (a), n is the number of repeats and represents an integer from 1 to 4.)

The compound in which R ₁ and R ₂ in the formula (a-1) are organic groups represented by the formulas (2a) to (2c), (3a) to (3i), or (4a) to (4d) can be obtained by an addition reaction between the compound represented by the formula (a) and an acid anhydride represented by the following formulas (5a) to (5c), (6a) to (6i), or (7a) to (7d):

Next, a method for synthesizing the compound represented by formula (a-1) will be described.
The compound represented by the formula (a-1) can be obtained by the reaction of the alcohol represented by the formula (a) with an acid anhydride, as described above. This reaction is preferably carried out without a catalyst, but an acid or a base may be used as a catalyst.
When a catalyst is used, examples of the catalyst that can be used include acidic compounds such as hydrochloric acid, sulfuric acid, methanesulfonic acid, trifluoromethanesulfonic acid, paratoluenesulfonic acid, nitric acid, trifluoroacetic acid, and trichloroacetic acid; metal hydroxides such as sodium hydroxide, potassium hydroxide, calcium hydroxide, and magnesium hydroxide; amine compounds such as triethylamine, tripropylamine, and tributylamine; heterocyclic compounds such as pyridine, dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, imidazole, triazole, and tetrazole; and quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylpropylammonium hydroxide, trimethylbutylammonium hydroxide, trimethylcetylammonium hydroxide, trioctylmethylammonium hydroxide, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, tetramethylammonium acetate, and trioctylmethylammonium acetate. These catalysts may be used alone or in combination of two or more. Among these, triethylamine, pyridine and dimethylaminopyridine are preferred.
There is no particular limitation on the amount of catalyst used, but it is generally preferable to use 0.001 to 5 parts by mass, if necessary, per 100 parts by mass of the total weight of the alcohol represented by formula (a) and the acid anhydride.

This reaction is preferably carried out without a solvent, but an organic solvent may be used. The amount of organic solvent used is 0.005 to 1 part by weight, preferably 0.005 to 0.7 parts, and more preferably 0.005 to 0.5 parts (i.e., 50% by weight or less), per part of the total amount of the acid anhydride and the alcohol represented by formula (a) as reaction substrates. If the amount of organic solvent used exceeds 1 part by weight per part by mass of the reaction substrates, the reaction proceeds extremely slowly, which is not preferred.
Specific examples of usable organic solvents include alkanes such as hexane, cyclohexane, and heptane; aromatic hydrocarbon compounds such as toluene and xylene; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and anone; ethers such as diethyl ether, tetrahydrofuran, and dioxane; and ester compounds such as ethyl acetate, butyl acetate, and methyl formate.

This reaction proceeds sufficiently even at a temperature of around 20°C. Due to reaction time considerations, the reaction temperature is preferably 30 to 200°C, more preferably 40 to 200°C, and especially preferably 40 to 150°C. In particular, when this reaction is carried out without a solvent, the acid anhydride volatilizes, so the reaction is preferably carried out at 120°C or below, with 30 to 120°C or 40 to 120°C being particularly preferred.

Theoretically, the reaction ratio between the acid anhydride and the alcohol represented by formula (a) is preferably equimolar, but this can be changed as needed. The specific reaction ratio is preferably such that, for each equivalent of acid anhydride group, 0.001 to 2 equivalents, more preferably 0.01 to 1.5 equivalents, and even more preferably 0.1 to 1.2 equivalents of alcohol represented by formula (a) are added in functional group equivalents. In the present invention, the compound represented by formula (a-1) is preferably liquid. To obtain a liquid compound represented by formula (a-1), ideally, an equimolar or greater amount of alcohol represented by formula (a) is used. However, fluidity is important when a filler is added. To ensure this fluidity, it is acceptable to slightly disrupt the viscosity balance within the range that maintains solidity (softening point 50°C or higher). Specifically, the ratio of alcoholic hydroxyl groups to acid anhydride equivalents is preferably 0.85 to 1.20 molar equivalents, and particularly preferably 0.90 to 1.1.0 molar equivalents.

The reaction time depends on the reaction temperature, catalyst amount, etc., but from the perspective of industrial production, a long reaction time is undesirable because it consumes a lot of energy. Furthermore, a reaction time that is too short means that the reaction is too rapid, which is undesirable from a safety standpoint. The preferred range is 1 to 48 hours, preferably 1 to 36 hours, more preferably 1 to 24 hours, and even more preferably 2 to 10 hours.

After the reaction is complete, if a catalyst was used, the catalyst is removed by neutralization, washing with water, adsorption, etc., and the solvent is distilled off to obtain the desired compound represented by formula (a-1). On the other hand, if the reaction was carried out without a catalyst, the solvent can be distilled off as needed to obtain the desired compound represented by formula (a-1). Furthermore, if a solvent was used, the solvent can be removed to obtain the desired compound represented by formula (a-1). Furthermore, if no solvent or catalyst was used, the desired compound represented by formula (a-1) can be obtained by directly extracting the product.

The most suitable production method involves reacting the acid anhydride and the alcohol represented by formula (a) at 40 to 150°C in the absence of a catalyst, removing the solvent, and then isolating the product.

The method for synthesizing the alcohol represented by formula (a) is not particularly limited, but examples include known methods involving the reaction of PDC and ethylene glycol. Specifically, PDC and ethylene glycol are reacted in the presence of an acid catalyst, and the resulting reaction solution is cooled and crystallized, followed by suction filtration to obtain the compound represented by formula (a). The method for purifying the compound represented by formula (a) is not particularly limited, and simple washing with a solvent or the like may be sufficient, but a crystallization method is preferred, as the resulting compound has high crystallinity.

The mixture of the present invention contains a compound represented by formula (a-1) and a carboxylic acid anhydride compound. As described above, the compound represented by formula (a-1) is obtained by reacting an alcohol represented by formula (a) with an acid anhydride. However, the mixture of the present invention can be obtained by adding an excess amount of the acid anhydride without going through a separation process or the like. Therefore, in the mixture of the present invention, preferred acid anhydrides are those represented by formulas (5a) to (5c), (6a) to (6i), or (7a) to (7d), and particularly preferred are those represented by formulas (6a) to (6e).

In the mixture of the present invention, the content of the compound represented by formula (a-1) and the acid anhydride is preferably 20% to 100%. The content can be appropriately changed depending on the compatibility with the thermosetting resin composition and the physical properties of the cured product, and can be calculated from the area ratio of ^1H -NMR, although it is not particularly limited.

Next, the curable resin composition of the present invention will be described.
The curable resin composition of the present invention may contain the compound represented by formula (a-1) either alone or in combination. The curable resin composition may also contain the acid anhydride used in synthesizing the compound represented by formula (a-1).

The curable resin composition of the present invention may contain an epoxy resin in addition to the compound represented by formula (a-1). Any epoxy resin commonly used in conventional epoxy resin compositions can be used without particular limitations. Examples include epoxidized novolac resins of phenols and aldehydes, such as phenol novolac epoxy resins and orthocresol novolac epoxy resins; diglycidyl ethers of bisphenol A, bisphenol F, bisphenol S, and alkyl-substituted bisphenols; glycidylamine epoxy resins obtained by reacting epichlorohydrin with polyamines such as diaminodiphenylmethane and isocyanuric acid; alicyclic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; diglycidyl isocyanurate, triglycidyl isocyanurate, and silsesquioxane compounds. These may be used alone or in combination. Among these epoxy resins, those with high heat resistance are preferred. Specifically, glycidyl ether epoxy resins and alicyclic epoxy resins are preferred from the standpoints of melt viscosity, coloration of the resulting cured product, and glass transition temperature.

The curable resin composition of the present invention may contain a curing agent in addition to the compound represented by formula (a-1). Examples of curing agents that can be used in combination include amine compounds, acid anhydride compounds having an unsaturated ring structure, acid anhydrides having an organosiloxane skeleton, amide compounds, phenolic compounds, and carboxylic acid compounds. Among these, amine compounds, acid anhydride compounds, phenolic compounds, and carboxylic acid compounds are preferred.

Specific examples of curing agents that can be used include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, dicyandiamide, polyamide resin synthesized from a linolenic acid dimer and ethylenediamine, phthalic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride. , butanetetracarboxylic anhydride, bicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride, methylbicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride, bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, terpene diphenol, 4,4'-biphenol, 2,2'-biphenol, 3,3',5,5'-tetramethyl-[1,1'-biphenyl]-4,4'-diol, hydroquinone, resorcinol, naphthalenediol, trimethylsilyl p-(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, phenols (phenol, alkyl-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, dihydroxynaphthalene, etc.), formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, o-hydroxybenzaldehyde, p-hydroxyacetophenone, o-hydroxyacetophenone, dicyclopentadiene, fluoro Examples of suitable polycondensates include fural, 4,4'-bis(chloromethyl)-1,1'-biphenyl, 4,4'-bis(methoxymethyl)-1,1'-biphenyl, 1,4'-bis(chloromethyl)benzene, and 1,4'-bis(methoxymethyl)benzene, as well as modified products thereof; halogenated bisphenols such as tetrabromobisphenol A; imidazole; trifluoroborane-amine complexes; guanidine derivatives; and condensates of terpenes and phenols, but are not limited to these. These may be used alone or in combination of two or more.

The compounding ratio of the epoxy resin and the curing agent containing the compound represented by formula (a-1) is preferably such that, per equivalent of epoxy groups in the epoxy resin, the active groups in the thermosetting resin curing agent that can react with the epoxy groups (such as acid anhydride groups or hydroxyl groups) are 0.5 to 1.5 equivalents (considering carboxylic acid as monofunctional and acid anhydride as monofunctional), and particularly preferably 0.5 to 1.2 equivalents. If the ratio is less than 0.5 equivalents or more than 1.5 equivalents per equivalent of epoxy groups, curing may be incomplete and good cured physical properties may not be achieved.

A curing catalyst can be added to the curable resin composition of the present invention as needed. Examples of curing catalysts include 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 2,4-diamino-6(2'-methylimidazole(1'))ethyl-s-triazine, 2,4-diamino-6(2'-undecylimidazole(1'))ethyl-s-triazine, 2,4-diamino-6(2'-ethylimidazole(1'))ethyl-s-triazine, and 2,4-diamino-6(2'-ethylimidazole(1')). Various imidazoles such as 2-phenyl-3,5-dihydroxymethylimidazole, 2-phenyl-4-hydroxymethyl-5-methylimidazole, 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole, 2,4-diamino-6-(2'-methylimidazole(1'))ethyl-s-triazine, 2,4-diamino-6-(2'-methylimidazole(1'))ethyl-s-triazine/isocyanuric acid adduct, 2-methylimidazole/isocyanuric acid 2:3 adduct, 2-phenylimidazole/isocyanuric acid adduct, 2-phenyl-3,5-dihydroxymethylimidazole, 2-phenyl-4-hydroxymethyl-5-methylimidazole, 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole, and the like, as well as mixtures of these imidazoles with phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, naphthyl esters, and the like. salts with polycarboxylic acids such as tallow dicarboxylic acid, maleic acid, oxalic acid, etc.; amides such as dicyandiamide; diaza compounds such as 1,8-diaza-bicyclo[5.4.0]undecene-7, and their salts such as tetraphenylborate and phenol novolac; salts with the above polycarboxylic acids or phosphinic acids; quaternary ammonium salts such as tetrabutylammonium bromide, cetyltrimethylammonium bromide, trioctylmethylammonium bromide, hexadecyltrimethylammonium hydroxide (preferably C1 to C20 alkylammonium salts); triphenylphosphine, tri(toluyl)phosphine, tetrabutylammonium bromide, cetyltrimethylammonium bromide, trioctylmethylammonium bromide, hexadecyltrimethylammonium hydroxide, etc. Examples of curing accelerators include phosphines and phosphonium compounds such as phenylphosphonium bromide and tetraphenylphosphonium tetraphenylborate, phenols such as 2,4,6-trisaminomethylphenol, metal compounds such as amine adducts, tin octoate, zinc octoate, zinc stearate, copper naphthenate, and cobalt naphthenate, and microencapsulated curing accelerators in which these curing accelerators are microencapsulated. Imidazole compounds are preferred in the present invention. The curing accelerator is typically used in an amount of 0.001 to 15 parts by mass, preferably 0.01 to 5 parts by mass, per 100 parts by mass of epoxy resin.

If necessary, the curable resin composition of the present invention may contain additives other than those mentioned above, such as commonly used additives for epoxy resins, such as dyes, fluorescent brighteners, reinforcing materials, fillers, white pigments or other pigments, nucleating agents, surfactants, plasticizers, viscosity modifiers, flow modifiers, flame retardants, antioxidants, ultraviolet absorbers, and light stabilizers.

Examples of the filler include, but are not limited to, crystalline silica, fused silica, antimony oxide, titanium oxide, magnesium oxide, zirconium oxide, aluminum hydroxide, magnesium hydroxide, and alumina. These may be used alone or in combination of two or more. The amount of inorganic filler blended is preferably 1 to 1,000 parts by mass, and more preferably 1 to 800 parts by mass, per 100 parts by mass of the total amount of the curable resin composition.

The curable resin composition of the present invention can be obtained by uniformly dispersing and mixing the various components described above. While there are no particular limitations on the method, examples include thoroughly and uniformly stirring and mixing the various components using a mixer or similar device, then kneading or melt-kneading them using a mixing roll, extruder, kneader, roll, extruder, or similar device, followed by cooling and pulverization. The kneading or melt-kneading conditions can be determined based on the types and amounts of the components, and are not particularly limited. Kneading for 5 to 40 minutes at a temperature between 20 and 200°C is preferred. If the kneading temperature is below 20°C, the dispersibility of the components decreases, making sufficient kneading difficult. At temperatures above 200°C, the crosslinking reaction of the resin composition may proceed, potentially resulting in hardening of the resin composition.

The curable resin composition of the present invention is preferably capable of being pressure (tablet) molded at room temperature of 0 to 30°C before heat molding. Pressure molding can be performed, for example, under conditions of 0.01 to 10 MPa for approximately 1 to 5 seconds. There are no particular restrictions on the mold used during pressure (tablet) molding, but it is preferable to use one consisting of a pestle (upper mold) and a mortar (lower mold) made of a ceramic material, a fluorine-based resin material, or the like.

The curable resin composition of the present invention is useful in semiconductor encapsulation applications that require a high glass transition temperature.

The present invention will be explained in more detail below based on examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" in the text are by mass.

Example 1 Synthesis of a Compound Represented by Formula (a-1) of the Present Invention (Step 1) Synthesis of Intermediate Compound 1 Represented by Formula (1) 73.6 parts of PDC (2-pyrone-4,6-dicarboxylic acid), 447 parts of ethylene glycol, and 1.0 parts of 36% hydrochloric acid were placed in a 1000 ml separable flask and heated to 70°C to dissolve. The mixture was then heated to 120°C while reducing the pressure to 4.5 kPa·s, and reacted for 6 hours while distilling off water. After confirming the completion of the reaction, the mixture was allowed to cool and then cooled in a refrigerator overnight to crystallize. The solid was recovered by suction filtration and purified by recrystallization four times with an excess amount of ethanol. The resulting wet cake was dried at 60°C for 3 hours to obtain intermediate compound 1 represented by the following formula (1) as a white solid in a 35% yield. ^{The 1} H-NMR measurement results for compound 1 are shown in FIG. 1.

(Step 2) Synthesis of Compound 2 Represented by Formula (2) 5.4 parts of intermediate compound 1 represented by formula (1) synthesized in Step 1 and 18.9 parts of Rikacid MH-T were placed in a 500 ml separable flask, heated to 120°C, and reacted for 3 hours. After confirming the completion of the reaction, the flask was stored as is, and 21 parts of compound 2 represented by formula (2) below were obtained as a liquid in a yield of 87%. ^{The 1} H-NMR measurement results of compound 2 are shown in Figure 1. 78% of the reaction product was unreacted Rikacid MH-T.

Comparative Example 1 Synthesis of Comparative Compound (Step 3) Synthesis of Compound 3 Represented by Formula (3) Compound 3 represented by the following formula (3) was obtained in a liquid form (45 parts, 87% yield) in the same manner as in Step 2, except that TCD alcohol DM (manufactured by OXEA) was used instead of intermediate compound 1. 78% of the reaction product was unreacted Rikacid MH-T.

[Examples 2 and 3, Comparative Example 2] Preparation of Thermosetting Resin Composition The components were mixed according to the blending amounts (parts by mass) listed in Table 1. The resulting composition was stirred and degassed for 2 minutes at 1,200 rpm using a planetary centrifugal mixer ARV-310 (manufactured by Thinky), and the compatibility of the resulting composition was then visually confirmed. Compatibility was confirmed visually, with a ◯ indicating that the composition was not cloudy and an × indicating that the composition was cloudy. Next, the blended thermosetting resin composition was poured into a Teflon mold measuring 35 mm x 50 mm and 0.8 mm thick, and heated at 120°C for 1 hour and 150°C for 3 hours to obtain a cured product.

(Evaluation of cured properties of thermosetting resin composition)
The cured properties of the resulting cured product were evaluated using a dynamic viscoelasticity measuring device.
DMA measurement conditions Dynamic viscoelasticity measuring instrument: Hitachi High-Tech Science DMS6100
Measurement temperature range: 15 to 270°C
Temperature rise rate: 2°C/min Frequency: 1 Hz
Measurement mode: Tensile vibration Tg: The peak point of tan δ was taken as Tg.

(Measurement of Water Absorption of Thermosetting Resin Composition)
The resulting cured product was cut into 10 x 10 mm pieces using a laser cutter, dried in an oven at 120°C for 2 hours, and the initial weight was measured. Thereafter, the product was immersed in Millipore water for 24 hours (in a 25°C, 20% humidity environmental testing room), lightly wiped, and then weighed. The water absorption rate was evaluated from the change in weight before and after the test.

The compound of Example 1 is liquid, has good compatibility with epoxy resins, and is easy to work with, and the cured compositions of Examples 2 and 3 were confirmed to have excellent heat resistance (Tg) and low water absorption.

The compound of the present invention can be used as a curing agent for, for example, epoxy compounds, and therefore can be suitably used in applications for thermosetting resin compositions that are cured by the action of heat.

Claims (7)

A compound represented by the following formula (a-1):
(In formula (a-1), R ₁ and R ₂ each represent one selected from the following formulae (2a) to (2c), (3a) to (3i), or (4a) to (4d). n is the number of repetitions and represents an integer of 1 to 4.)
(The * symbol indicates that the group is bonded to the oxygen atom in formula (a-1).) The compound according to claim 1, wherein n in formula (a-1) is 1. A mixture comprising the compound according to claim 1 or 2 and a carboxylic acid anhydride compound. A curable resin composition comprising the compound according to claim 1 or 2 , or the mixture according to claim 3 . The curable resin composition according to claim 4 , further comprising an epoxy resin. The curable resin composition according to claim 4 or 5 , further comprising a curing agent. The curable resin composition according to claim 4 , which is a semiconductor encapsulant.