Epoxy resin and method for producing the same, and epoxy resin composition

Abstract

To provide an epoxy resin that exhibits superior flexibility along with high reactivity and curability, a resin composition containing the epoxy resin, and a method for producing the epoxy resin.SOLUTION: The present invention provides an epoxy resin represented by the formula (1). (In the formula (1), R1 represents a C2-10 bivalent aliphatic hydrocarbon group, a plurality of R1 may be the same or different. n represents 2-30. Two X1 may be the same or different, representing a hydrogen atom or a group represented by the formula (2), where at least one X1 is a group represented by the formula (2). Two X2 may be the same or different, representing a hydrogen atom or a group represented by the formula (2), where at least one X2 is a group represented by the formula (2). Z1 and Z2 independently represent a bivalent linkage group).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an epoxy resin, a method for producing the same, and an epoxy resin composition. [Background technology]

[0002] Epoxy resins are used in a wide range of applications, including as sealing materials for electric and electronic components, molding materials, casting materials, laminating materials, composite materials, adhesives, and paints, because they give cured products with excellent mechanical properties, heat resistance, moisture resistance, and electrical properties. There have been many developments in which epoxy resins have been modified to improve desired properties by adjusting their structures. In recent years, there has been an increasing demand for epoxy resins with flexible skeletons, which can improve properties such as adhesiveness and vibration damping.

[0003] Examples of epoxy resins having a flexible backbone include polytetramethylene glycol (PTMG) type epoxy resins, and development using these is being carried out. For example, Patent Document 1 discloses a technique for obtaining a thermosetting epoxy resin composition having excellent flexibility, impact resistance, and water resistance by using an epoxy resin obtained by reacting a PTMG-type epoxy resin with an epihalohydrin and reducing the total chlorine content contained as an impurity to a specific value or less. Furthermore, Patent Document 2 discloses a technology that provides a layer made of a resin composition that contains an amine having a PTMG skeleton as an epoxy resin curing agent in addition to components such as epoxy resin and synthetic rubber, and further contains a specific component within a specific range in content, thereby making it possible to obtain a dry film for coverlay that has excellent folding resistance, electrical insulation, solder heat resistance, folding resistance, and the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-308601 A [Patent Document 2] JP 2011-233883 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, in recent years, there has been an increasing demand for epoxy resins having a flexible backbone, but the epoxy resin compositions disclosed in Patent Documents 1 and 2 have a problem of low reactivity in the reaction between the epoxy resin and a curing agent, etc. When curing is insufficient due to low reactivity, it is difficult to obtain desired properties compared to epoxy resins with high reactivity, and production efficiency is reduced, and other problems are likely to occur, leaving room for improvement.

[0006] The present invention has been made in consideration of the above-mentioned problems in the conventional art, and an object of the present invention is to provide an epoxy resin having excellent flexibility and high reactivity and curability, a resin composition containing the epoxy resin, and a method for producing the epoxy resin. [Means for solving the problem]

[0007] As a result of intensive research aimed at solving the above problems, the present inventors found that the above problems can be solved by having an aliphatic skeleton to ensure flexibility, while introducing a glycidylamine structure into the skeleton to further improve reactivity, and thus arrived at the present invention.

[0008] The gist of the present invention is as follows. [1] An epoxy resin represented by the following formula (1): [ka] (In the above formula (1), R 1 represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, and multiple R 1 may be the same or different. n is 2 to 30. Two X 1are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X 1 is a group represented by the above formula (2). 2 are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X 2 is a group represented by the above formula (2). 1 and Z 2 each independently represents a divalent bonding group. [2] R in the above formula (1) 1 is a divalent aliphatic hydrocarbon having 2 to 4 carbon atoms. [3] The epoxy resin according to [2], wherein the divalent aliphatic hydrocarbon having 2 to 4 carbon atoms is a divalent aliphatic hydrocarbon represented by -(CH2)4-. [4] The epoxy resin according to any one of [1] to [3], wherein n is 4 to 20. [5] Z above 1 and Z 2 The epoxy resin according to any one of [1] to [4], wherein the epoxy resin is represented by the following formula (3): [ka] (In the above formula (3), * represents a bonding site with the nitrogen atom or oxygen atom in the above formula (1), * on the aromatic side represents a bonding site with the nitrogen atom in the above formula (1), and * on the carbonyl carbon side represents a bonding site with the oxygen atom in the above formula (1).) [6] Any of [1] to [5] whose epoxy equivalent is 100 to 3000 g / eq. The epoxy resin described herein. [7] An epoxy resin composition comprising the epoxy resin according to any one of [1] to [6] and a curing agent. [8] The epoxy resin composition according to [7], wherein the content of the curing agent is 0.1 to 1000 parts by mass based on 100 parts by mass of the epoxy resin. [9] The epoxy resin composition according to [7] or [8], wherein the curing agent is at least one selected from the group consisting of polyfunctional phenol compounds, polyisocyanate compounds, amine compounds, acid anhydride compounds, imidazole compounds, amide compounds, mercaptan compounds, cationic polymerization initiators, and organic phosphine compounds.

[10] A cured product of the epoxy resin composition according to any one of [7] to [9].

[11] A method for producing an epoxy resin, comprising a halohydrination step of reacting an amine compound represented by the following formula (4) with epihalohydrin: [ka] (In the above formula (4), R 1 represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, and multiple R 1 may be the same or different. n is 2 to 30. Z 1 and Z 2 Each independently represents a divalent bonding group.

[12] The halohydrination step is a step of adding the epihalohydrin to the amine compound to obtain a 1,2-halohydrin compound, The method for producing an epoxy resin according to

[11] , further comprising an epoxidation step of reacting the 1,2-halohydrin compound with an alkaline compound to carry out epoxidation after the halohydrination step. Effect of the Invention

[0009] According to the present invention, it is possible to provide an epoxy resin having excellent flexibility and high reactivity and curability, a resin composition containing the epoxy resin, and a method for producing the epoxy resin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention is not limited to the following description, and can be modified as desired without departing from the scope of the present invention. In this specification, when a numerical value or physical property value is expressed using "~", the lower limit and upper limit values ​​that are the endpoints are included. In this specification, "mass %", "mass ppm", and "parts by mass" have the same meaning as "weight %", "weight ppm", and "parts by weight", respectively. In addition, in this specification, the expression "A or B" can be read as "at least one selected from the group consisting of A and B." In addition, although a number of embodiments are described in this specification, various conditions in each embodiment may be applied to each other to the extent that they are applicable.

[0011] <Epoxy resin> [Epoxy resin composition] An epoxy resin according to one embodiment of the present invention (hereinafter also simply referred to as "epoxy resin") is an epoxy resin represented by the following formula (1).

[0012] [ka]

[0013] In the above formula (1), R 1 represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, and multiple R 1 may be the same or different. n is 2 to 30. Two X 1 are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X 1 is a group represented by the above formula (2). 2 are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X 2 is a group represented by the above formula (2). 1 and Z 2 each independently represents a divalent bonding group.

[0014] As described above, conventional epoxy resins have a problem of low reactivity with curing agents, etc. When curing is insufficient due to low reactivity, it is difficult to obtain desired properties compared to epoxy resins with high reactivity, and production efficiency is likely to decrease. On the other hand, the epoxy resin according to the present embodiment has at least one epoxy group directly bonded to a nitrogen atom at each of both ends. As a result of extensive research, the present inventors have found that an epoxy resin having such an end structure has superior reactivity with a curing agent and the like compared to conventional epoxy resins. Furthermore, in the epoxy resin, up to four epoxy groups can be bonded to a nitrogen atom, and from this viewpoint, there is also an effect that the reactivity can be easily improved.

[0015] R in the above formula (1) 1 is not particularly limited as long as it is a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms. The number of carbon atoms is preferably 2 to 8, more preferably 2 to 6, and further preferably 2 to 4. In addition, The hydride group may have a straight chain structure, a branched chain structure, or a cyclic structure. It is preferable that the carbon number is equal to or greater than the lower limit of the above range, since this provides an effect of increasing chemical stability, and it is preferable that the carbon number is equal to or less than the upper limit of the above range, from the viewpoint of industrial availability.

[0016] R 1Specific examples of the olefin include a 1,2-ethylene group, a 1,2-propylene group, a 1,3-propylene group, a 1,2-butylene group, a 1,3-butylene group, a 1,4-butylene group, a 1,2-pentylene group, a 1,3-pentylene group, a 1,4-pentylene group, a 1,5-pentylene group, a 1,2-hexylene group, a 1,3-hexylene group, a 1,4-hexylene group, a 1,5-hexylene group, and a 1,6-hexylene group. Examples of such groups include a xylene group, a 1,7-heptylene group, a 1,8-octylene group, a 1,9-nonylene group, and a 1,10-decylene group. From the viewpoint of industrial availability, a 1,2-ethylene group (-(CH2)2-), a 1,2-propylene group (-CH2-CH(CH3)-), or a 1,4-butylene group (-(CH2)4-) is preferred, with a 1,4-butylene group (-(CH2)4-) being particularly preferred.

[0017] The above formula (1) is R 1 These may be the same or different. 1 At least one R 1 It is preferable that R satisfies the above preferred embodiment, and all R 1 It is more preferable that the above-mentioned preferred embodiments are satisfied.

[0018] In the above formula (1), n ​​is not particularly limited as long as it is 2-30, but is preferably 2-20, more preferably 4-20, further preferably 5-18, and particularly preferably 7-15. When the n is equal to or greater than the lower limit of the above range, a resin having excellent flexibility can be obtained, and when the n is equal to or less than the upper limit of the above range, a resin having excellent curability can be obtained.

[0019] The two X in the above formula (1) 1 are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X 1 is not particularly limited as long as it is a group represented by the following formula (2), but from the viewpoint of improving reactivity, 1 is preferably a group represented by the above formula (2).

[0020] The two X in the above formula (1) 2 The above X, including the favorable conditions, 1 The condition of X can be applied. 1 and X 2 can be set independently of each other.

[0021] Z in the above formula (1) 1 and Z 2 are not particularly limited as long as they are each independently a divalent linking group. The divalent linking group may be an organic group capable of linking an oxygen atom and a nitrogen atom, for example, a divalent hydrocarbon group which may have a substituent, and at least one of the carbon atoms constituting the hydrocarbon group is -C(=O)-, -C(=O)O-, -O-, -S-, -NH-, or -NR 10 -, wherein R 10 is a monovalent hydrocarbon group, and from the viewpoint of efficiently introducing a flexible skeleton, Particularly preferred is an embodiment in which at least one of the carbon atoms is substituted with -C(=O)-.

[0022] The structure of the divalent hydrocarbon group is not particularly limited, and may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination of these, but from the viewpoint of the curability of the resin, it is preferable that the divalent hydrocarbon group has an aromatic hydrocarbon group. In addition, the divalent hydrocarbon group may have a straight chain structure, a branched chain structure, or a cyclic structure.

[0023] The number of carbon atoms constituting the above divalent hydrocarbon group is not particularly limited, but from the viewpoint of ensuring flexibility due to the aliphatic structure, it is preferably 2 to 20, more preferably 4 to 15, even more preferably 6 to 12, and particularly preferably 7 to 9.

[0024] The structure of the above-mentioned substituent is not particularly limited, and examples thereof include a halogen group, -C≡N, -NH3, -C(=O)OH, -C(=O)OR', -C(=O)R', -SH, and -SiR a Rb R c , -BH2, or -SeH, and R', R a , R b , R c each independently represents hydrogen or an alkyl group having 1 to 20 carbon atoms.

[0025] Z 1 and Z 2 From the viewpoint of productivity, at least one of the above is preferably specifically represented by the following formula (3), 1 and Z 2 It is more preferable that both of the above are represented by the following formula (3).

[0026] [ka]

[0027] In the above formula (3), * represents a bonding site with the nitrogen atom or oxygen atom in the above formula (1), * on the aromatic side represents a bonding site with the nitrogen atom in the above formula (1), and * on the carbonyl carbon side (carbonyl group side) represents a bonding site with the oxygen atom in the above formula (1).

[0028] The epoxy equivalent of the epoxy resin is not particularly limited, but should be 80 to 5000 g / eq. It is preferable that the g / eq is 100 to 3000, and more preferable that the g / eq is 200 to 2000. g / eq is more preferable, and 250 to 1000 g / eq is particularly preferable. It is preferable that the epoxy equivalent is equal to or more than the lower limit of the above range in terms of expressing flexibility due to the aliphatic structure, and it is preferable that the epoxy equivalent is equal to or less than the upper limit of the above range in terms of obtaining good curability.

[0029] [Epoxy resin manufacturing method] The method for producing the above-mentioned epoxy resin is not particularly limited, and the epoxy resin can be produced by a known method or a combination of known methods. One example of the production method, which is another embodiment of the present invention, is a method for producing an epoxy resin (hereinafter, also simply referred to as "a method for producing an epoxy resin") that includes a halohydrination step of reacting an amine compound represented by the following formula (4) with epihalohydrin.

[0030] [ka]

[0031] In the above formula (4), R 1 represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, and multiple R 1 may be the same or different. n is 2 to 30. Z 1 and Z 2 Each of independently represents a divalent linking group. R in the above formula (4) 1 , n, Z 1 , and Z 2 The condition is R in the above formula (1). 1 , n, Z 1 , and Z 2 can be applied in the same way. The above-mentioned method for producing an epoxy resin may include a step other than the halohydrination step.

[0032] The amine compound represented by the formula (4) can be produced by a known method or a combination of known methods. In addition, the amine compound represented by the formula (4) may be a commercially available product.

[0033] The method for producing the above epoxy resin will now be described in detail.

[0034] (Halohydrination process) The method for producing an epoxy resin includes a halohydrination step of reacting an amine compound represented by the above formula (4) with epihalohydrin. The method for carrying out the halohydrination is not particularly limited, and an example of the method is a method of adding epihalohydrin to an amine compound to obtain a 1,2-halohydrin compound.

[0035] The type of epihalohydrin is not particularly limited, and examples thereof include epichlorohydrin, epibromohydrin, epiiodohydrin, and the like. From the viewpoint of industrial availability, epichlorohydrin is preferred.

[0036] The amounts of the amine compound and epihalohydrin used are not particularly limited and can be appropriately set depending on the structure of the epoxy resin to be obtained. For example, the molar ratio of the amount of epihalohydrin to the amino group of the amine compound (epihalohydrin / amino group of the amine compound) may be 2 to 30, 5 to 25, or 8 to 20.

[0037] The method for adding epihalohydrin to an amine compound is not particularly limited, and examples thereof include a method in which an amine compound and epihalohydrin are placed in a reaction vessel and reacted with each other.

[0038] The reaction temperature for the above addition reaction is not particularly limited, but is preferably 40 to 150°C, more preferably 50 to 120°C, and even more preferably 60 to 100°C. The reaction pressure of the above reaction is not particularly limited, but is, for example, preferably 0.05 to 1 MPa, more preferably 0.08 to 0.5 MPa, and further preferably 0.1 to 0.2 MPa. The reaction time for the above reaction is not particularly limited, but is preferably, for example, 0.5 to 20 hours, more preferably 1 to 15 hours, and even more preferably 2 to 10 hours. The reaction atmosphere for the above reaction is not particularly limited, and may be an air atmosphere or an inert gas atmosphere such as nitrogen or argon.

[0039] The number of epihalohydrins to be added to the amine compound represented by formula (4) can be adjusted by carrying out a treatment such as adding a protecting group to the nitrogen atom in the amine compound represented by formula (4) before the above reaction. In this case, the protecting group may be removed after the above reaction or after the epoxidation step described later.

[0040] The halohydrination step can be carried out using a catalyst, if necessary. Examples of the catalyst include compounds such as tertiary amines and / or their salts, imidazoles and / or their salts, diazabicyclo compounds, phosphines, phosphonium salts, and quaternary ammoniums and / or their salts. Examples of tertiary amines and / or salts thereof include triethylamine, tributylamine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and N-methylpiperazine. Examples of imidazoles and / or salts thereof include 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2,4-dicyano-6-[2-methylimidazolyl-(1)]-ethyl-S-triazine, and the like. Examples of diazabicyclo compounds include 1,5-diazabicyclo(5.4.0)-7-undecane, 1,5-diazabicyclo(4.3.0)-5-nonene, and 1,4-diazabicyclo(2.2.2)octane. Examples of the phosphines include tributylphosphine, triphenylphosphine, tris(dimethoxyphenyl)phosphine, tris(hydroxypropyl)phosphine, and tris(cyanoethyl)phosphine. Examples of the phosphonium salts include tetraphenylphosphonium tetraphenylborate, methyltributylphosphonium tetraphenylborate, and methyltricyanoethylphosphonium tetraphenylborate. Examples of quaternary ammoniums and / or salts thereof include tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium hydroxide, triethylmethylammonium bromide, tetraethylammonium chloride, benzyltrimethylammonium chloride, and benzyltrimethylammonium hydroxide. The above-mentioned catalysts may be used alone or in combination of two or more kinds. Generally, the catalyst can be used in an amount of 0.001 to 10 parts by mass per 100 parts by mass of the amine compound.

[0041] (Epoxidation process) The method for producing an epoxy resin may further include an epoxidation step in which an alkaline compound is allowed to act on the 1,2-halohydrin body to perform epoxidation after the halohydrination step. Specifically, the action is a reaction in which HX (X is a halogen atom) is eliminated from the 1,2-halohydrin body by the alkaline compound, and an epoxide is produced by the reaction. From the viewpoint of reaction efficiency, this reaction is preferably carried out in the presence of water.

[0042] The type of alkaline compound is not particularly limited, and examples thereof include sodium hydroxide, potassium hydroxide, potassium carbonate, calcium carbonate, cesium carbonate, etc. Among these, sodium hydroxide is preferred from the viewpoints of availability of raw materials and cost.

[0043] The amounts of the 1,2-halohydrin and alkaline compound used are not particularly limited and can be appropriately set depending on the structure of the epoxy resin to be obtained. For example, the molar ratio of the alkaline compound to the amount of the 1,2-halohydrin (alkaline compound / 1,2-halohydrin) may be 0.9 to 3.0, 1.0 to 2.0, or 1.1 to 1.5.

[0044] The method for reacting the alkaline compound with the 1,2-halohydrin is not particularly limited, and examples thereof include a method in which an alkaline compound is added to a vessel containing the 1,2-halohydrin. The 1,2-halohydrin compound is a compound having a structure represented by the following formula (5): In formula (5), X is a halogen atom, and the wavy line represents a bond to an atom or atomic group not represented in the formula. The 1,2-halohydrin compound in this embodiment represents a compound in which the ring of epihalohydrin added to an amine compound is cleaved to form the following structure.

[0045] [ka]

[0046] The treatment temperature for the treatment involving the action of the alkaline compound is not particularly limited, but is preferably 20 to 120°C, more preferably 30 to 100°C, and even more preferably 40 to 80°C. The treatment pressure for the above treatment is not particularly limited, but is, for example, preferably 0.05 to 1 MPa, more preferably 0.08 to 0.5 MPa, and further preferably 0.1 to 0.2 MPa. The treatment time for the above treatment is not particularly limited, but is preferably, for example, 0.1 to 6 hours, more preferably 0.25 to 4 hours, and even more preferably 0.5 to 2 hours. The treatment atmosphere for the above treatment is not particularly limited, and may be an air atmosphere or an inert gas atmosphere such as nitrogen or argon.

[0047] The method for producing an epoxy resin preferably further includes a post-treatment step, if necessary, after the reaction is completed. For example, the post-treatment step involves removing insoluble by-product salts by filtration or by washing with water, and then removing unreacted epihalohydrin by distillation under reduced pressure, thereby obtaining a target epoxy resin with high purity. Furthermore, if the epoxy resin obtained as described above has too much saponifiable halogen, it can be reprocessed to obtain a purified epoxy resin with a sufficiently reduced amount of saponifiable halogen. That is, the crude epoxy resin obtained by the reaction is redissolved in an inert organic solvent such as isopropyl alcohol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, dioxane, methoxypropanol, or dimethyl sulfoxide, and an alkali metal hydroxide is added as a solid or aqueous solution to perform a re-ring-closing reaction at a temperature of preferably 30 to 120°C, more preferably 40 to 110°C, and even more preferably 50 to 100°C for preferably 0.1 to 8 hours, more preferably 0.3 to 7 hours, and even more preferably 0.5 to 6 hours, and then the excess alkali metal hydroxide and secondary salt are removed by a method such as water washing, and the organic solvent is further distilled under reduced pressure and / or steam distilled to obtain an epoxy resin with a reduced amount of hydrolyzable halogen. If the reaction temperature is too low or the reaction time is too short, the re-ring-closing reaction may not proceed. Furthermore, if the reaction temperature is too high or the reaction time is too long, the reaction will proceed, but there is a risk of problems such as an increase in molecular weight, an increase in epoxy equivalent, and an increase in viscosity.

[0048] <Epoxy resin composition> An epoxy resin composition (hereinafter also simply referred to as "epoxy resin composition") which is another embodiment of the present invention is an epoxy resin composition containing the above-mentioned epoxy resin and a curing agent. The epoxy resin composition may contain components other than the epoxy resin and the curing agent.

[0049] The content of the epoxy resin in the epoxy resin composition is not particularly limited, but is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 50% by mass or more, in terms of solid content (calculated based on components excluding the solvent), and is preferably 99.9% by mass or less, more preferably 99% by mass or less, even more preferably 95% by mass or less, and particularly preferably 90% by mass or less. If the content is equal to or higher than the lower limit of the above range, it is preferable in that the flexibility of the epoxy resin is easily exhibited, whereas if the content is equal to or lower than the upper limit of the above range, it is preferable in that other components such as a curing agent can be contained in necessary amounts. The epoxy resin may be used alone or in combination of two or more kinds. In this specification, the term "solid content" refers to components excluding the solvent, and includes not only solid epoxy resins but also semi-solid and viscous liquid substances.

[0050] [Hardening agent] The type of curing agent is not particularly limited, and any of those generally known as epoxy resin curing agents can be used. For example, at least one selected from the group consisting of polyfunctional phenol compounds, polyisocyanate compounds, amine compounds, acid anhydride compounds, imidazole compounds, amide compounds, mercaptan compounds, cationic polymerization initiators, and organic phosphine compounds can be mentioned. Among these, from the viewpoint of easily expressing the flexibility of the epoxy resin, acid anhydride compounds, amine compounds, or imidazole compounds are preferred, and amine compounds are particularly preferred.

[0051] Among these, polyfunctional phenol-based compounds or aromatic amine-based curing agents are preferred from the viewpoint of improving heat resistance, stress resistance, moisture absorption resistance, flame retardancy, etc. Also, acid anhydride-based curing agents or amide-based curing agents are preferred from the viewpoint of heat resistance, etc. Also, imidazoles are preferred from the viewpoint of sufficiently progressing the curing reaction and improving heat resistance.

[0052] The content of the curing agent relative to 100 parts by mass of the epoxy resin is not particularly limited, but is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.2 parts by mass or more, and particularly preferably 0.5 parts by mass or more, and is preferably 2000 parts by mass or less, more preferably 1000 parts by mass or less, even more preferably 500 parts by mass or less, and particularly preferably 200 parts by mass or less. When the content is equal to or higher than the lower limit of the above range, a cured product having an excellent gelation rate can be obtained, and when the content is equal to or lower than the upper limit of the above range, flexibility due to the epoxy resin is easily exhibited. The condition of "the content of the curing agent relative to 100 parts by mass of the epoxy resin" (this "epoxy resin" is the above-mentioned epoxy resin) is the same as "the content of the curing agent relative to 100 parts by mass of all epoxy resin components contained in the epoxy resin composition" (this "all epoxy resin components" includes both the above-mentioned epoxy resins and epoxy resins other than the above-mentioned epoxy resins).

[0053] The curing agent may be used alone or in combination of two or more. When two or more curing agents are used in combination, they may be mixed in advance to prepare a mixed curing agent, or when mixing the components of the curable resin composition, each component of the curing agent may be added separately and mixed at the same time.

[0054] (Polyfunctional phenolic compounds) Specific examples of polyfunctional phenolic compounds include bisphenol A, bisphenol F, Various polyhydric phenols such as bisphenol S, bisphenol AD, hydroquinone, resorcin, methylresorcin, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol novolac resins, cresol novolac resins, phenol aralkyl resins, biphenyl aralkyl resins, naphthol aralkyl resins, terpene phenol resins, dicyclopentadiene phenol resins, bisphenol A novolac resins, trisphenol methane type resins, naphthol novolac resins, brominated bisphenol A, or brominated phenol novolac resins; various phenols and benzaldehyde Examples of the phenolic resins include polyhydric phenol resins obtained by condensation reaction of various aldehydes such as aldehyde, hydroxybenzaldehyde, crotonaldehyde, or glyoxal; polyhydric phenol resins obtained by condensation reaction of xylene resin with phenols; co-condensation resins of heavy oils or pitches with phenols and formaldehydes; phenol-benzaldehyde-xylylene dimethoxide polycondensates; phenol-benzaldehyde-xylylene dihalide polycondensates; phenol-benzaldehyde-4,4'-dimethoxide biphenyl polycondensates; and phenol-benzaldehyde-4,4'-dihalide biphenyl polycondensates. These polyfunctional phenolic compounds may be used alone or in any combination of two or more kinds in any blend ratio.

[0055] The content of the polyfunctional phenol-based compound curing agent relative to 100 parts by mass of the epoxy resin is preferably 0.1 to 1,000 parts by mass, more preferably 500 parts by mass or less, further preferably 300 parts by mass or less, and particularly preferably 100 parts by mass or less.

[0056] (Polyisocyanate compounds) Specific examples of polyisocyanate compounds include polyisocyanate compounds such as tolylene diisocyanate, methylcyclohexane diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, dimer acid diisocyanate, trimethylhexamethylene diisocyanate, lysine triisocyanate, etc. Furthermore, polyisocyanate compounds obtained by reacting these polyisocyanate compounds with compounds having at least two active hydrogen atoms such as amino groups, hydroxyl groups, carboxyl groups, water, etc., or trimers to pentamers of the above polyisocyanate compounds, etc., can be mentioned. These polyisocyanate compounds may be used alone or in any combination of two or more kinds in any blend ratio.

[0057] The content of the polyisocyanate compound curing agent relative to 100 parts by mass of the epoxy resin is preferably 0.1 to 1,000 parts by mass, more preferably 500 parts by mass or less, further preferably 300 parts by mass or less, and particularly preferably 100 parts by mass or less.

[0058] (Amine compounds) Examples of the amine-based compound include aliphatic amines, polyether amines, alicyclic amines, and aromatic amines.

[0059] Examples of aliphatic amines other than tertiary amines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminopropane, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, bis(hexamethylene)triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-hydroxyethylethylenediamine, and tetra(hydroxyethyl)ethylenediamine.

[0060] Examples of polyetheramines other than tertiary amines include triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis(propylamine), polyoxypropylene diamine, and polyoxypropylene triamines.

[0061] Examples of alicyclic amines other than tertiary amines include isophoronediamine, methacenediamine, N-aminoethylpiperazine, bis(4-amino-3-methyldicyclohexyl)methane, bis(aminomethyl)cyclohexane, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, and norbornenediamine.

[0062] Examples of aromatic amines other than tertiary amines include tetrachloro-p-xylylenediamine, m-xylylenediamine, p-xylylenediamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisole, 2,4-toluenediamine, 2,4-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diamino-1,2-diphenylethane, 2,4-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, m-aminophenol, m-aminobenzylamine, benzyldimethylamine, 2-(dimethylaminomethyl)phenol, triethanolamine, methylbenzylamine, α-(m-aminophenyl)ethylamine, α-(p-aminophenyl)ethylamine, diaminodiethyldimethyldiphenylmethane, α,α'-bis(4-aminophenyl)-p-diisopropylbenzene, and m-tolidine.

[0063] The amine-based compounds other than tertiary amines may be used alone or in any combination of two or more kinds in any blending ratio.

[0064] The amine-based compound other than the above-mentioned tertiary amine is preferably used so that the equivalent ratio of the functional group in the curing agent to the epoxy group in all the epoxy resin components contained in the epoxy resin composition is in the range of 0.8 to 1.5. If it is within this range, it is preferable because unreacted epoxy groups and functional groups of the curing agent are unlikely to remain.

[0065] Examples of tertiary amines include 1,8-diazabicyclo(5,4,0)undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol.

[0066] The tertiary amines may be used alone or in any combination of two or more kinds in any blend ratio.

[0067] The tertiary amine is preferably used so that the equivalent ratio of the functional group in the curing agent to the epoxy group in all epoxy resin components contained in the epoxy resin composition is in the range of 0.8 to 1.5. If it is within this range, it is preferable because unreacted epoxy groups and functional groups of the curing agent are less likely to remain.

[0068] (Acid anhydride compound) Examples of the acid anhydride compound include acid anhydrides and modified products of acid anhydrides. Examples of the acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, dodecenylsuccinic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic anhydride, poly(ethyloctadecanedioic) anhydride, poly(phenylhexadecanedioic) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexa Examples of the anhydride include hydrophthalic anhydride, methylhimic anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic anhydride, methylcyclohexene tetracarboxylic anhydride, ethylene glycol bistrimellitate dianhydride, HET anhydride, Nadic anhydride, methylnadic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, and 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride.

[0069] The modified acid anhydride may be, for example, the above-mentioned acid anhydride modified with glycol. Examples of the glycol that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol, or neopentyl glycol; or polyether glycols such as polyethylene glycol, polypropylene glycol, or polytetramethylene ether glycol. Furthermore, copolymer polyether glycols of two or more of these glycols and / or polyether glycols may be used.

[0070] In the modified acid anhydride, it is preferable to modify the acid anhydride with 0.4 moles or less of glycol per mole of acid anhydride. When the amount of modification is equal to or less than the upper limit, the viscosity of the epoxy resin composition does not become too high, and the workability tends to be good, and the rate of the curing reaction with the epoxy resin also tends to be good.

[0071] The acid anhydride compounds may be used alone or in any combination of two or more in any amount.

[0072] When an acid anhydride compound is used, it is preferable to use it so that the equivalent ratio of the functional group in the curing agent to the epoxy group in all epoxy resin components in the epoxy resin composition is in the range of 0.8 to 1.5. If it is within this range, it is preferable because unreacted epoxy groups and functional groups of the curing agent are unlikely to remain.

[0073] (Imidazole compounds) Examples of imidazole compounds include 2-phenylimidazole, 2-ethyl-4(5)-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl Examples of the imidazoles include 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins and the above imidazoles. Note that since imidazoles have catalytic activity, they can generally be classified as curing accelerators, but in this specification, they are classified as curing agents.

[0074] The imidazole-based compound may be used alone or in any combination and ratio of two or more. When the imidazole-based compound is used, it is preferable to use the imidazole-based compound in an amount of 0.1 to 20 mass% (solid content equivalent) based on the total of all epoxy resin components and the imidazole-based compound in the epoxy resin composition.

[0075] (Amide compounds) Examples of the amide-based compound include dicyandiamide or its derivatives, polyamide resins, etc. The amide-based curing agent may be used alone or in any combination and ratio of two or more. When using an amide-based compound, it is preferable to use the amide-based curing agent in an amount of 0.1 to 20 mass% (solid content equivalent) based on the total of all epoxy resin components and amide-based compounds in the epoxy resin composition.

[0076] (Mercaptan compounds) Specific examples of the mercaptan compound include polysulfide type mercaptan compounds, thioester type mercaptan compounds, and thioether type mercaptan compounds. These mercaptan compounds may be used alone or in any combination of two or more in any blend ratio.

[0077] The content of the mercaptan-based compound curing agent relative to 100 parts by mass of the epoxy resin is preferably 0.1 to 1,000 parts by mass, more preferably 500 parts by mass or less, further preferably 300 parts by mass or less, and particularly preferably 100 parts by mass or less.

[0078] (Cationic polymerization initiator) The cationic polymerization initiator generates cations by heat or irradiation with active energy rays, and examples of the initiator include aromatic onium salts. - , BF4 - , AsF6 - , PF6 - , CF3SO3 2- , or B(C6F5)4 - and an aromatic cation component containing an atom of iodine, sulfur, nitrogen, phosphorus, etc. Diaryl iodonium salts and triaryl sulfonium salts are particularly preferred. These cationic polymerization initiators may be used alone or in any combination of two or more kinds in any blending ratio.

[0079] The content of the cationic polymerization initiator curing agent relative to 100 parts by mass of the epoxy resin is preferably 0.01 to 20 parts by mass, more preferably 10 parts by mass or less, further preferably 5 parts by mass or less, and particularly preferably 2 parts by mass or less.

[0080] (Organophosphine compounds) Specific examples of the organic phosphine compound include tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, and phenylphosphine. These organic phosphine compounds may be used alone or in any combination of two or more in any ratio.

[0081] The content of the organic phosphine compound curing agent relative to 100 parts by mass of the epoxy resin is preferably 0.01 to 20 parts by mass, more preferably 10 parts by mass or less, further preferably 5 parts by mass or less, and particularly preferably 2 parts by mass or less.

[0082] (Other hardeners) In the epoxy resin composition, other curing agents can be used in addition to the above curing agents. The type of other curing agent is not particularly limited, and any agent generally known as a curing agent for epoxy resins can be used. These other curing agents may be used alone or in combination of two or more.

[0083] [Cure accelerator] The epoxy resin composition preferably contains a curing accelerator. By containing the curing accelerator, it is possible to shorten the curing time and lower the curing temperature, and it is possible to easily obtain a desired cured product. The curing accelerator is not particularly limited, but specific examples include organic phosphines, phosphorus compounds such as phosphonium salts, tetraphenylboron salts, organic acid dihydrazides, boron halide amine complexes, aromatic ureas, and aliphatic ureas.

[0084] Phosphorus compounds that can be used as curing accelerators include triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkyl alkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, Examples of the organic phosphines include organic phosphines such as dialkylarylphosphines or alkyldiarylphosphines; complexes of these organic phosphines with organic borons; and compounds obtained by adding quinone compounds such as maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone, or compounds such as diazophenylmethane to these organic phosphines.

[0085] Among the curing accelerators, organic phosphines or phosphonium salts are preferred, and organic phosphines are most preferred. The curing accelerators may be used alone or in any combination and ratio of two or more. When dicyandiamide is used as the curing agent, it is preferable to use aromatic urea or aliphatic urea as the curing accelerator.

[0086] The curing accelerator is preferably used in a range of 0.1 to 20 parts by mass relative to 100 parts by mass of the total epoxy resin components in the epoxy resin composition. More preferably, it is 0.5 parts by mass or more, and even more preferably, it is 1 part by mass or more, while it is more preferably 15 parts by mass or less, and even more preferably, it is 10 parts by mass or less. When the content of the curing accelerator is equal to or more than the lower limit, a good curing acceleration effect can be obtained, while when it is equal to or less than the upper limit, the desired curing properties are easily obtained.

[0087] [Other epoxy resins] The epoxy resin composition may further contain other epoxy resins in addition to the above-mentioned epoxy resins. By containing other epoxy resins, the heat resistance, stress resistance, moisture absorption resistance, flame retardancy, etc. of the epoxy resin composition can be improved.

[0088] The other epoxy resins include all epoxy resins other than the above-mentioned epoxy resins. Specific examples include bisphenol A type epoxy resins, trisphenolmethane type epoxy resins, anthracene type epoxy resins, phenol-modified xylene resin type epoxy resins, bisphenol cyclododecyl type epoxy resins, bisphenol diisopropylidene resorcin type epoxy resins, bisphenol F type epoxy resins, bisphenol AD ​​type epoxy resins, hydroquinone type epoxy resins, methylhydroquinone type epoxy resins, dibutylhydroquinone type epoxy resins, resorcin type epoxy resins, methylresorcin type epoxy resins, biphenol type epoxy resins, tetramethylbiphenol type epoxy resins, tetramethylbisphenol F type epoxy resins, dihydroxydiphenyl ether type epoxy resins, epoxy resins derived from thiodiphenols, dihydroxynaphthalene type epoxy resins, dihydroxyanthracene type epoxy resins, dihydroxydihydroanthracene type epoxy resins, Examples of epoxy resins that can be used include epoxy resins derived from phenol-hydroxybenzaldehyde condensates, epoxy resins derived from phenol-crotonaldehyde condensates, epoxy resins derived from phenol-glyoxal condensates, epoxy resins derived from co-condensation resins of heavy oils or pitches, phenols, and formaldehydes, epoxy resins derived from diaminodiphenylmethane, epoxy resins derived from aminophenols, epoxy resins derived from xylylenediamine, epoxy resins derived from methylhexahydrophthalic acid, and epoxy resins derived from dimer acids. These may be used alone or in any combination of two or more in any blend ratio.

[0089] Among the other epoxy resins, from the viewpoints of the fluidity of the epoxy composition and further the heat resistance, moisture absorption resistance, and flame retardancy of the cured product, bisphenol A type epoxy resins, tetramethylbiphenol type epoxy resins, 4,4'-biphenol type epoxy resins, biphenyl aralkyl type epoxy resins, phenol aralkyl type epoxy resins, dihydroxyanthracene type epoxy resins, dicyclopentadiene type epoxy resins, orthocresol novolac type epoxy resins, and trisphenolmethane type epoxy resins are particularly preferred.

[0090] When the epoxy resin composition contains other epoxy resins, the content thereof is preferably 0.01 to 60 parts by mass, more preferably 40 parts by mass or less, even more preferably 30 parts by mass or less, particularly preferably 20 parts by mass or less, and more preferably 1 part by mass or more, relative to 100 parts by mass of all epoxy resin components in the composition.

[0091] [Inorganic filler] The epoxy resin composition may contain an inorganic filler. Examples of inorganic fillers include fused silica, crystalline silica, glass powder, alumina, calcium carbonate, calcium sulfate, talc, boron nitride, and the like. These may be used alone or in any combination of two or more in any mixing ratio. Among these, crushed and / or spherical fused and / or crystalline silica powder fillers are preferred for semiconductor sealing applications.

[0092] By using the inorganic filler, when the epoxy resin composition is used as a semiconductor encapsulant, the thermal expansion coefficient of the semiconductor encapsulant can be made closer to that of the internal silicon chip or lead frame, and the moisture absorption amount of the entire semiconductor encapsulant can be reduced, thereby improving the solder crack resistance.

[0093] The average particle size of the inorganic filler is usually 1 to 50 μm, preferably 1.5 to 40 μm, and more preferably 2 to 30 μm. When the average particle size is equal to or more than the lower limit, the melt viscosity does not become too high and the flowability is not easily decreased, which is preferable, and when the average particle size is equal to or less than the upper limit, the filler is not easily clogged in narrow gaps in a mold during molding, which is preferable because the filling property of the material is easily improved.

[0094] When an inorganic filler is used in the epoxy resin composition, the content of the inorganic filler in the epoxy resin composition is preferably 60 to 95 mass % (solid content equivalent).

[0095] [Release agent] A mold release agent can be blended into the epoxy resin composition. Examples of the mold release agent include natural waxes such as carnauba wax, synthetic waxes such as polyethylene wax, higher fatty acids such as stearic acid or zinc stearate or metal salts thereof, and hydrocarbon mold release agents such as paraffin. These may be used alone or in any combination of two or more in any blending ratio.

[0096] When a release agent is blended in the epoxy resin composition, the blending amount of the release agent is preferably 0.1 to 5.0 parts by mass, more preferably 0.5 to 3.0 parts by mass, based on 100 parts by mass of the total epoxy resin components in the epoxy resin composition. When the blending amount of the release agent is within the above range, it is preferable because good releasability can be exhibited while maintaining the curing characteristics of the curable resin composition.

[0097] [Coupling agent] It is preferable to add a coupling agent to the epoxy resin composition. It is preferable to use the coupling agent together with the inorganic filler, and by adding the coupling agent, it is possible to improve the adhesion between the epoxy resin matrix and the inorganic filler. Examples of the coupling agent include a silane coupling agent and a titanate coupling agent.

[0098] Examples of the silane coupling agent include epoxy silanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; amino silanes such as γ-aminopropyltriethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, and γ-ureidopropyltriethoxysilane; mercapto silanes such as 3-mercaptopropyltrimethoxysilane; vinyl silanes such as p-styryltrimethoxysilane, vinyltrichlorosilane, vinyltris(β-methoxyethoxy)silane, vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane; and epoxy, amino, or vinyl polymeric silanes.

[0099] Examples of titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tri(N-aminoethyl aminoethyl) titanate, diisopropyl bis(dioctyl phosphate) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, and bis(dioctyl pyrophosphate)ethylene titanate.

[0100] The coupling agent may be used alone or in any combination and ratio of two or more kinds.

[0101] When a coupling agent is used in the epoxy resin composition, the amount of the coupling agent is preferably 0.1 to 3.0 parts by mass relative to 100 parts by mass of the total epoxy resin components. When the amount of the coupling agent is equal to or more than the lower limit, the effect of improving the adhesion between the epoxy resin matrix and the inorganic filler by adding the coupling agent tends to be improved, while when the amount of the coupling agent is equal to or less than the upper limit, the coupling agent is less likely to bleed out from the obtained cured product, which is preferable.

[0102] [Other ingredients] The epoxy resin composition may contain components (other components) other than the above-mentioned components. Examples of other components include solvents, flame retardants, plasticizers, reactive diluents, and pigments, and these may be added as necessary. However, the epoxy resin composition does not in any way prevent the addition of components other than those listed above.

[0103] Examples of the flame retardant include halogen-based flame retardants such as brominated epoxy resins or brominated phenol resins; antimony compounds such as antimony trioxide; phosphorus-based flame retardants such as red phosphorus, phosphate esters, or phosphines; nitrogen-based flame retardants such as melamine derivatives; and inorganic flame retardants such as aluminum hydroxide or magnesium hydroxide.

[0104] [Check the ingredients] Whether the epoxy resin according to the above-described embodiment or other blending components are blended in the epoxy resin composition can be confirmed by carrying out qualitative analysis and / or quantitative analysis using a nuclear magnetic resonance apparatus, a mass spectrometer and / or a chromatograph after separation and purification of the epoxy resin composition.

[0105] <Cured product> A cured product (hereinafter, also simply referred to as "cured product"), which is another embodiment of the present invention, is a cured product of the above-mentioned epoxy resin composition. The cured product is obtained by curing the above-mentioned epoxy resin composition, and "curing" here means intentionally curing the epoxy resin by heat and / or light, etc. The degree of the curing may be controlled depending on the desired physical properties, applications, etc.

[0106] The curing method for curing the epoxy resin composition to produce a cured product varies depending on the components and amounts of the components in the epoxy resin composition, the form of the compounded product, etc., but typically includes heating conditions of 5 seconds to 180 minutes at 50 to 200° C. This heating is preferably performed in a two-stage process of primary heating at 50 to 160° C. for 5 seconds to 30 minutes and secondary heating at 90 to 200° C., which is 40 to 120° C. higher than the primary heating temperature, for 1 minute to 150 minutes, in order to reduce curing defects.

[0107] When producing a cured product as a semi-cured product, the curing reaction of the epoxy resin composition may be allowed to proceed to an extent that allows the shape to be maintained by heating, etc. When the epoxy resin composition contains a solvent, most of the solvent can be removed by techniques such as heating, reducing pressure, or air drying, but 5% by mass or less of the solvent may remain in the semi-cured product.

[0108] The presence of epoxy resin in the cured product can be confirmed by decomposing the cured product using an appropriate method, and then analyzing it using an appropriate analytical method such as nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy, or various types of chromatography to identify the epoxy resin in the cured product.

[0109] <Application> The above-mentioned epoxy resin has excellent reactivity, and the epoxy resin composition and the cured product using the same can be used in many applications, mainly in the coating field, civil engineering field, or electrical field, from the viewpoint of excellent miscibility, heat resistance, elastic modulus, etc. The epoxy resin can be suitably used, among others, for coatings (compositions); binders for adhesives; base materials for prepregs; base materials for laminates; semiconductor encapsulants; coatings; base materials for fiber-reinforced plastics (FRP); or electrical and electronic materials; etc. Specifically, the epoxy resin composition can be suitably used for coatings; adhesives; prepregs; laminates; or semiconductor encapsulants; and the cured product of the resin composition is preferably included in coatings; joints; fiber-reinforced plastics (FRP); semiconductor encapsulants; or electrical and electronic materials; etc. EXAMPLES

[0110] The present invention will be described in more detail below based on examples, but the present invention is not limited to the following examples. Note that 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 ​​of the examples.

[0111] <Evaluation of characteristics> [Epoxy equivalent of epoxy resin] The epoxy equivalent of the epoxy resin was measured based on JIS K 7236.

[0112] [Gelation rate of cured product] The cured product was cut into test pieces of 10 mm x 10 mm x 4 mm size, dried at 120 ° C for 2 hours, and then the dry mass (A1) was measured. The test pieces were then placed in a 20 cc screw bottle and immersed in 15 mm tetrahydrofuran at 23 ° C for 2 hours. The test pieces were removed from the screw bottle, dried at 80 ° C for 2 hours and at 120 ° C for 1 hour, and their mass (A2) was measured. The "residual mass ratio (%) = 100 × A2 / A1" was calculated, and this was used as an index of the gelation rate.

[0113] Regarding the structure of the epoxy resin, the average value of n specified in the structure represented by the above formula (1) and the number of groups in the structure represented by the above formula (2) among X1 and X2 are determined by proton nuclear magnetic resonance spectroscopy ( 1 The specific measurement conditions are as follows: Measurement equipment: AVANCE NEO 600 spectrometer (Bruker) ·Measurement frequency: 600MHz Flip angle: 45° Number of times: 16 ·Measurement temperature: 25℃ Measurement sample: 30 mg of the measurement sample was placed in a sample tube, deuterated chloroform was added as a solvent, and the sample was dissolved at 25°C.

[0114] <Production and evaluation of epoxy resin> [Example 1] A separable flask reactor equipped with a thermometer, a dropping funnel, a stirrer, a nitrogen inlet tube, and a cooling tube was charged with 50 parts by mass of Elasmer 650P (polytetramethylene oxide-di-para-aminobenzoate, amine value 126 mg KOH / g, manufactured by Kumiai Chemical Industry Co., Ltd.), 166 parts by mass of epichlorohydrin, 97 parts by mass of propylene glycol monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.), and 100 parts by mass of water, and the mixture was heated to 90° C. and reacted for 6 hours. Thereafter, the mixture was allowed to cool to 50°C, and while maintaining the temperature at 50°C, 22 parts by mass of a 48% by mass aqueous sodium hydroxide solution was continuously added dropwise over 30 minutes, after which the reaction was carried out at 50°C for 30 minutes. Thereafter, the aqueous layer was separated from the oil, and the salts generated by the reaction, residual sodium hydroxide, etc. were removed from the resin solution, and the reaction was stopped. The temperature of the resulting reaction solution was gradually increased, and the pressure in the system was reduced, and the system was maintained at 150°C and 5 mmHg for 30 minutes, and propylene glycol monomethyl ether, excess epichlorohydrin, and water were completely removed from the system. Thereafter, the system was returned to normal pressure while nitrogen was sealed in the system, and 63 parts by mass of methyl isobutyl ketone was added to obtain a methyl isobutyl ketone solution of crude resin. 3 parts by mass of 48% by mass aqueous sodium hydroxide solution was added to this solution and reacted at 50°C for 1 hour, after which 83 parts by mass of methyl isobutyl ketone and 150 parts by mass of water were added to separate the aqueous layer, and then the aqueous layer removed with 150 parts by mass of water was repeatedly washed with water several times until it became neutral, obtaining a methyl isobutyl ketone solution of epoxy resin. Methyl isobutyl ketone was distilled off from this solution under heating and reduced pressure, and the temperature was maintained at 150°C and 5 mmHg for 30 minutes until methyl isobutyl ketone was completely removed, yielding liquid epoxy resin (1). The epoxy equivalent of the resulting epoxy resin was 495 g / eq. The epoxy resin has a structure represented by the above formula (1), and on average, n in formula (1) is 9 and a total of four X's bonded to nitrogen atoms are contained in the resulting epoxy resin. 1 and X 2 Among them, the number of groups of the structure represented by the above formula (2) was 2.6 on average.

[0115] [Example 2] Into an apparatus similar to that used in Example 1, 80 parts by mass of Elasmer 1000P (polytetramethylene oxide-di-para-aminobenzoate, manufactured by Kumiai Chemical Industry Co., Ltd., amine value 90.6 mgKOH / g), 191 parts by mass of epichlorohydrin, 112 parts by mass of propylene glycol monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.), and 116 parts by mass of water were charged, heated to 90°C, and reacted for 9 hours. Thereafter, the mixture was allowed to cool to 50°C, and while maintaining the temperature at 50°C, 26 parts by mass of a 48% by mass aqueous sodium hydroxide solution was continuously added dropwise over 30 minutes, after which the reaction was carried out at 50°C for 60 minutes. Thereafter, the aqueous layer was separated from the oil, and the salts generated by the reaction, residual sodium hydroxide, etc. were removed from the resin solution, and the reaction was stopped. The temperature of the resulting reaction solution was gradually increased, and the pressure in the system was reduced, and the system was maintained at 150°C and 5 mmHg for 30 minutes, and propylene glycol monomethyl ether, excess epichlorohydrin, and water were completely removed from the system. Thereafter, the system was returned to normal pressure while nitrogen was sealed in the system, and 94 parts by mass of methyl isobutyl ketone was added to obtain a methyl isobutyl ketone solution of crude resin. 12 parts by mass of 48% by mass aqueous sodium hydroxide solution was added to this solution and reacted at 50°C for 1 hour, after which 126 parts by mass of methyl isobutyl ketone and 200 parts by mass of water were added to separate the aqueous layer, and then the aqueous layer removed with 200 parts by mass of water was repeatedly washed with water several times until it became neutral, obtaining a methyl isobutyl ketone solution of epoxy resin. Methyl isobutyl ketone was distilled off from this solution under heating and reduced pressure, and the temperature was maintained at 150°C and 5 mmHg for 30 minutes until methyl isobutyl ketone was completely removed, yielding liquid epoxy resin (2). The epoxy equivalent of the resulting epoxy resin was 686 g / eq. The epoxy resin has a structure represented by the above formula (1), and on average, n in formula (1) is 14 and a total of four X's bonded to nitrogen atoms are present in the resulting epoxy resin. 1 and X 2 Among them, the number of groups of the structure represented by the above formula (2) was 3.2 on average.

[0116] [Reference example 1] A polyoxytetramethylene glycol-type epoxy resin (3) was produced by the method described in Patent Document 1 (Synthesis Example 1). The epoxy equivalent of the obtained epoxy resin was 450 g / eq.

[0117] [Example 3] 15 parts by mass of the epoxy resin (1) produced in Example 1, 2.9 parts by mass of jER Cure ST14 (an amine compound manufactured by Mitsubishi Chemical Corporation), and 0.1 parts by mass of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Chemical Industry Co., Ltd.) were mixed to obtain a resin composition. The obtained composition was poured into a mold and heated at 100°C for 2 hours, and then heated at 170°C for 1 hour to obtain a cured epoxy resin product. The gel fraction of the obtained cured product was evaluated by the method described above, and the results are shown in Table 1.

[0118] [Example 4, Comparative Examples 1 and 2] In Example 3, the epoxy resin, the curing agent, and the curing accelerator were used in the compositions shown in Table 1. Except for the above change, an epoxy resin cured product was obtained in the same manner as in Example 3. The gel fraction of the obtained cured product was evaluated by the method described above, and the results are shown in Table 1.

[0119] The raw materials listed in Table 1 are as follows. jER828: Mitsubishi Chemical bisphenol A epoxy resin, epoxy equivalent 186g / eq

[0120] [Table 1]

[0121] From Table 1, it can be seen that the cured products of Examples 3 and 4 using the epoxy resin according to the embodiment of the present invention have a higher gelation rate than the cured products of Comparative Examples 1 and 2 using resins other than the epoxy resin. This result shows that the epoxy resin according to the embodiment of the present invention has excellent reactivity.

Claims

1. An epoxy resin represented by the following formula (1): 【Chemistry 1】 (In the above formula (1), R １ represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, １ may be the same or different. n is 2 to 30. Two X １ are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X １ is a group represented by the above formula (2). ２ are hydrogen atoms or groups represented by the above formula (2), which may be the same or different, and at least one X ２ is a group represented by the above formula (2). １ and Z ２ each independently represents a divalent bonding group.

2. R in the formula (1) １ The epoxy resin according to claim 1, wherein is a divalent aliphatic hydrocarbon having 2 to 4 carbon atoms.

3. The divalent aliphatic hydrocarbon having 2 to 4 carbon atoms is -(CH ２ ) ４ 3. The epoxy resin according to claim 2, wherein the epoxy resin is a divalent aliphatic hydrocarbon represented by the formula:

4. The epoxy resin according to claim 1, wherein n is 4 to 20.

5. Said Z １ and Z ２ The epoxy resin according to claim 1, wherein the epoxy resin is represented by the following formula (3): 【Chemistry 2】 (In the above formula (3), * represents a bonding site with the nitrogen atom or oxygen atom in the above formula (1), * on the aromatic side represents a bonding site with the nitrogen atom in the above formula (1), and * on the carbonyl carbon side represents a bonding site with the oxygen atom in the above formula (1).)

6. The epoxy resin according to claim 1, having an epoxy equivalent of 100 to 3000 g / eq.

7. An epoxy resin composition comprising the epoxy resin according to any one of claims 1 to 6 and a curing agent.

8. 8. The epoxy resin composition according to claim 7, wherein the content of the curing agent relative to 100 parts by mass of the epoxy resin is 0.1 to 1000 parts by mass.

9. The curing agent is at least one selected from the group consisting of polyfunctional phenol compounds, polyisocyanate compounds, amine compounds, acid anhydride compounds, imidazole compounds, amide compounds, mercaptan compounds, cationic polymerization initiators, and organic phosphine compounds. The epoxy resin composition according to claim 7,

10. A cured product of the epoxy resin composition according to claim 7.

11. A method for producing an epoxy resin, comprising a halohydrination step of reacting an amine compound represented by the following formula (4) with epihalohydrin: 【Chemistry 3】 (In the above formula (4), R １ represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, １ may be the same or different. n is 2 to 30. Z １ and Z ２ Each of independently represents a divalent bonding group.

12. the halohydrination step is a step of adding the epihalohydrin to the amine compound to obtain a 1,2-halohydrin compound, The method for producing an epoxy resin according to claim 11, further comprising an epoxidation step of reacting the 1,2-halohydrin compound with an alkaline compound to carry out epoxidation after the halohydrination step.

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