JP6252978B2 - Epoxy resin curing agent - Google Patents

Description

  The present invention relates to an epoxy resin curing agent, an epoxy resin composition, a cured product obtained by curing the composition, and a molded body containing the cured product.

  Liquid epoxy resins have a long history, and both hardeners and epoxy resins are easy to handle in liquid form. Therefore, the epoxy resin is a useful resin having an advantage of easily obtaining a solid molded body, and is used as a single resin or a composite material. The fields of application are wide and varied, such as dental materials, various structural materials, LED sealing materials, adhesives, paints including hard coats, etc. (see, for example, Patent Documents 1 and 2).

JP-A-6-32872 JP 2006-206783 A

  Mainly in an acid anhydride curing system, for example, when an epoxy resin of a type called an alicyclic epoxy resin typified by Celoxide CEL2021P manufactured by Daicel Chemical Industries, Ltd. is used, the resulting molded body has improved hardness and heat resistance. . Examples of the most standard epoxy resin include bisphenol A (BisA) type diglycidyl ether such as jER828 manufactured by Mitsubishi Chemical Corporation. Bisphenol A (BisA) type diglycidyl ether has been widely used for a long time due to its favorable characteristics that are thought to be derived from its bisphenol A bone nucleus and the like.

  In an acid anhydride-cured epoxy resin system, when an alicyclic epoxy resin is used, a molded article having a high surface hardness can be obtained. When the alicyclic epoxy resin is cured with a general low-viscosity liquid acid anhydride MeHHPA (methylhexahydrophthalic anhydride, for example, HN-5500 manufactured by Hitachi Chemical Co., Ltd.), a cured product (molded product) is obtained. ) Surface hardness is 2H in pencil hardness, which is higher than H in the case of BisA type epoxy resin. When the surface hardness of the molded body is high, when the final product in which the molded body is applied to the outer layer portion is used, the surface is hardly damaged. Therefore, the surface hardness of the molded body often becomes a factor that determines the product life. In addition, since the alicyclic epoxy resin does not have an aromatic ring in its molecular structure, it also has excellent performance in ultraviolet resistance (UV resistance) and color resistance. Therefore, when the alicyclic epoxy resin is used as a product member on the premise of receiving UV light, the product can have a long life. However, in recent years, the required performance in various applications has been increased, and a molded body using an alicyclic epoxy resin is required to further improve the surface hardness and UV coloring resistance and to expand its application range.

  On the other hand, when BisA-type diglycidyl ether is used, the resulting molded body is superior in flexibility, impact resistance, crack resistance, etc., compared to the case of using an alicyclic epoxy resin, and has a higher refractive index and UV irradiation. It can be said to have high performance in optically transparent applications that do not assume the above.

  Further, when BisA-type diglycidyl ether is used, the glass transition point (Tg) of the obtained molded product is one of important physical property values. If the glass transition point (Tg) can be improved, the cooling time until the mold can be released after pre-curing is shortened, and the number of molds can be reduced. In this case, if the number of molds on hand in the factory is the same, the production speed is improved and the mold-making efficiency is improved. That is, in the case of using BisA type diglycidyl ether, if the glass transition point (Tg) of the obtained molded body can be improved, the production efficiency of the molded body will be increased, but it cannot be said that it is sufficient yet, and further improvement. Is required.

  An object of the present invention is to further improve the surface hardness and UV color resistance of a cured product (molded product) obtained when an alicyclic epoxy resin is used, and further expand the application range of the molded product. Further, when BisA type diglycidyl ether is used, Tg, which is one of the physical property values of the obtained cured product (molded product), is to be improved.

As a result of intensive studies to achieve the above object, the present inventors can improve various physical properties and performance of the cured product obtained by using an acid anhydride having a specific structure as an epoxy resin curing agent. As a result, the present invention has been completed. That is, the present invention is as follows.
1. The epoxy resin hardening | curing agent containing the compound represented by following formula (1).
(In Formula (1), R shows a methyl group, an ethyl group, or a hydroxyl group, and n is an integer of 1-3.)
2. The epoxy resin curing agent according to claim 1, wherein the compound represented by the formula (1) is a compound represented by the following formula (2).
(In formula (2), X, Y and Z each independently represent a hydrogen atom, a methyl group, an ethyl group or a hydroxyl group.)
3. The epoxy resin curing agent according to claim 2, wherein the compound represented by the formula (2) is a compound represented by the following formula (3).
4). The epoxy resin curing agent according to claim 2, wherein the compound represented by the formula (2) is a compound represented by the following formula (4).
5. An epoxy resin composition comprising an epoxy resin and the curing agent according to any one of Items 1 to 4.
6). The epoxy resin composition according to claim 5, wherein the epoxy resin is at least one selected from the group consisting of an alicyclic epoxy resin, a nuclear hydrogenated BisA-type diglycidyl ether, and a BisA-type diglycidyl ether.
7). The epoxy resin composition according to claim 5 or 6, wherein the equivalent ratio of the curing agent to the epoxy resin (equivalent of curing agent / equivalent of epoxy resin) is 0.5 to 1.2.
8). The epoxy resin composition according to any one of items 5 to 7, further comprising a curing accelerator.
9. Item 9. The epoxy resin composition according to any one of Items 5 to 8, further comprising an antioxidant.
10. Item 10. The epoxy resin composition according to any one of Items 5 to 9, further comprising a UV absorber.
11. Item 11. The epoxy resin composition according to any one of Items 5 to 10, further comprising an inorganic filler.
12 A cured product obtained by curing the resin composition according to any one of Items 5 to 11.
13. A molded article comprising the cured product according to Item 12.

According to the present invention, when an alicyclic epoxy resin is used, the resulting cured product (molded product) has improved surface hardness and UV resistance, can be improved in performance, and can be further expanded in application range. Leads to.
Further, according to the present invention, when BisA-type diglycidyl ether is used, the obtained cured product (molded product) has an improved Tg which is one of the physical property values. For this reason, the cooling time until the mold can be released after pre-curing is short, and the number of molds is small. In this case, if the number of molds on hand in the factory is the same, the production speed is improved and the mold-making efficiency is improved. Therefore, according to this invention, since the production efficiency of a molded object goes up, it leads to the expansion of the application range of a molded object.

  Hereinafter, embodiments of the present invention (hereinafter also referred to as “present embodiments”) will be described in detail. In addition, the following embodiment is an illustration for demonstrating this invention, and this invention is not limited only to the embodiment.

  Hereinafter, an epoxy resin curing agent, an epoxy resin composition, a cured product obtained by curing the composition, a molded body, and the like will be described.

[Epoxy resin curing agent]
The epoxy resin hardening | curing agent of this embodiment contains the compound represented by following formula (1). Moreover, it is preferable that the epoxy resin hardening | curing agent of this embodiment consists of a compound represented by following formula (1).
(In Formula (1), R shows a methyl group, an ethyl group, or a hydroxyl group, and n is an integer of 1-3.)

  When an alicyclic epoxy resin is cured using an epoxy resin curing agent containing a compound represented by the above formula (1), the resulting cured product (molded product) is further improved in surface hardness and UV color resistance. Moreover, when BisA type | mold diglycidyl ether is hardened using the epoxy resin hardening | curing agent containing the compound represented by said Formula (1), the hardened | cured material (molded object) obtained will improve a glass transition point (Tg).

The compound represented by the above formula (1) is preferably a compound represented by the following formula (2).
(In formula (2), X, Y and Z each independently represent a hydrogen atom, a methyl group, an ethyl group or a hydroxyl group.)

  When an alicyclic epoxy resin is cured using an epoxy resin curing agent containing a compound represented by the above formula (2), the resulting cured product (molded product) is further improved in surface hardness and UV color resistance. Moreover, when the BisA type diglycidyl ether is cured using an epoxy resin curing agent containing a compound represented by the above formula (2), the resulting cured product (molded product) has a further improved glass transition point (Tg). .

The compound represented by the above formula (2) comprises a dimethyladamantane maleic anhydride monoadduct represented by the following formula (3) and a monoethyladamantane maleic anhydride monoadduct represented by the following formula (4). It is preferably at least one selected from the group.

  Cured alicyclic epoxy resin using an epoxy resin curing agent containing a compound represented by the above formula (3) and / or a compound represented by the above formula (4) to obtain a cured product (molded product) The surface hardness and UV color resistance are further improved. Moreover, when a BisA type diglycidyl ether is cured using an epoxy resin curing agent containing a compound represented by the above formula (3) and / or a compound represented by the above formula (4), a cured product (molded) is obtained. Body) has a further improved glass transition point (Tg).

  The epoxy resin hardening | curing agent of this embodiment can be used individually or in combination of 2 or more types.

  In addition, the epoxy resin curing agent of the present embodiment includes other acid anhydride epoxy resin curing agent, amine epoxy resin curing agent, phenolic epoxy resin curing agent as a curing agent component unless the effects of the present invention are impaired. You may make it contain. These may be used alone or in combination of two or more.

  The acid anhydride epoxy resin curing agent is not particularly limited, and examples thereof include tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic acid anhydride, trialkyltetrahydro Phthalic anhydride, methylcyclohexene tetracarboxylic dianhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, ethylene glycol bisanhydro trimellitate, glycerin (anhydro trimelli Tate) monoacetate, dodecenyl succinic anhydride, aliphatic dibasic acid polyanhydride, chlorendic anhydride and the like, and hydrogenated compounds of the above acid anhydrides. These may be contained alone or in combination.

  The amine-based epoxy resin curing agent is not particularly limited, and examples thereof include aliphatic amines such as diethylenetriamine, triethylenetetramine, N-aminoethylpiverazine, mensendiamine, isophoronediamine, m-xylylenediamine, m- Examples thereof include aromatic amines such as phenylenediamine, 4,4′-diaminodiphenylmethane, and 4,4′-diaminodiphenylsulfone.

  Although it does not specifically limit as a phenol-type epoxy resin hardening | curing agent, For example, a phenol novolak resin, a cresol novolak resin, a bisphenol novolak resin, a triazine modified phenol novolak resin etc. are mentioned.

[Method for Producing Compound Represented by Formula (1)]
The compound represented by the above formula (1) can be obtained by radically adding maleic anhydride to adamantanes.

  The raw material adamantane used in the present embodiment is not particularly limited, and examples thereof include adamantane, methyladamantane, dimethyladamantane, trimethyladamantane, ethyladamantane, diethyladamantane, triethyladamantane, adamantanol, adamantanediol, and adamantanetriol. It is done. Of these, dimethyladamantane or ethyladamantane is preferred from the viewpoint of pot life before curing and colorability of the cured product.

The feed molar ratio of the raw material is preferably in the range of 1 to 20 mol, more preferably in the range of 1.5 to 15 mol, and still more preferably in the range of 1.5 to 10 mol with respect to 1 mol of maleic anhydride. .
The reaction temperature when maleic anhydride is radically added to adamantane is preferably in the range of 120 to 180 ° C, more preferably in the range of 130 to 170 ° C, and still more preferably in the range of 150 to 170 ° C.
The reaction time after dropping the radical generator is preferably in the range of 0.1 to 10 hours, more preferably in the range of 0.5 to 5 hours, and still more preferably in the range of 1 to 3 hours.
The radical generator used in the present embodiment is preferably in the range of 0.001 to 0.1 mol, more preferably in the range of 0.005 to 0.05 mol, still more preferably 0.02 to 1 mol of maleic anhydride. The range is 0.07 mol. Preferred radical generators include di-tert-butyl peroxide, benzoyl peroxide, azobisisobutyronitrile and the like. Of these, di-tert-butyl peroxide is more preferable.
The reaction of adamantanes and maleic anhydride used in the present embodiment can be carried out without solvent or in a solvent. Although it does not specifically limit as a solvent to be used, For example, a dichlorobenzene, cyclohexanone, dibutyl ether etc. are mentioned. Solvent-free operation is preferred.
The reaction product thus obtained can be purified by distillation, crystallization, column separation or the like.

  More specifically, preferable conditions and the like are as follows. First, a reaction vessel is charged with 1 mol of maleic anhydride with respect to 1.6 mol of dimethyladamantane or ethyladamantane, and the temperature inside the reaction vessel is maintained at about 160 ° C. Next, a solution obtained by dissolving 5.5 mmol of di-tert-butyl peroxide in a small amount of dimethyladamantane or ethyladamantane as a radical generator is dropped into the reaction vessel over about 3 hours. The reaction is completed in about 3 hours from the end of dropping to obtain a reaction product. The obtained reaction product is distilled under reduced pressure to obtain the corresponding target product. However, the charging ratio, reaction temperature, and reaction time shown here can be appropriately changed so as to increase the yield of the target product, and other types of radical generators may be used.

[Epoxy resin composition]
The epoxy resin composition of the present embodiment includes an epoxy resin (hereinafter sometimes referred to as “main agent”) and the above-described epoxy resin curing agent. Although it does not specifically limit as a main ingredient used in this embodiment, For example, at least 1 sort (s) selected from the group which consists of alicyclic epoxy resin, nuclear hydrogenated BisA type diglycidyl ether, and BisA type diglycidyl ether is mentioned. . When such an epoxy resin is used as a main agent, the effect of the above-described epoxy resin curing agent is further exhibited, and the properties of the obtained cured product are further improved.

  In the present embodiment, the alicyclic epoxy resin is an epoxy resin having an alicyclic ring in its molecule and a part of the carbon-carbon bond forming the ring being shared with the epoxy ring. The alicyclic epoxy resin is not particularly limited, and examples thereof include 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate, vinylcyclohexene dioxide, and the like. Specifically, Daicel Chemical Industries, Ltd. Celoxide CEL2021P can be illustrated.

  The nuclear hydrogenated BisA type diglycidyl ether is not particularly limited, and examples thereof include YX8000 manufactured by Mitsubishi Chemical Corporation. The BisA-type diglycidyl ether is not particularly limited, and examples thereof include jER828 manufactured by Mitsubishi Chemical Corporation.

  Other epoxy resins are not particularly limited. For example, bisphenol F type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, biphenyl type epoxy resin, stilbene type epoxy resin, hydroquinone type epoxy resin, naphthalene skeleton type Of epoxy resin, tetraphenylolethane type epoxy resin, DPP type epoxy resin, trishydroxyphenylmethane type epoxy resin, dicyclopentadienephenol type epoxy resin, diglycidyl ether of bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct Examples thereof include glycidyl ethers having one epoxy group such as diglycidyl ether, phenyl glycidyl ether, cresyl glycidyl ether and the like. That. Moreover, the nuclear hydrogenation epoxy resin which is a nuclear hydrogenation thing of these epoxy resins is mentioned. These epoxy resin components can be used alone or in combination of two or more. Furthermore, an oxetane resin copolymerizable with an epoxy resin or various modified resins may be used.

In the epoxy resin composition of the present embodiment, the total content of the epoxy resin and the epoxy resin curing agent is preferably 20 to 100% by mass, more preferably 50 to 100% by mass, and further preferably 80 to 100% by mass.
In the epoxy resin composition of the present embodiment, the content ratio of the epoxy resin and the epoxy resin curing agent is such that the equivalent ratio of the curing agent to the epoxy resin (equivalent of curing agent / equivalent of epoxy resin) is in the following range. It is preferable to adjust so that. The equivalent ratio of the curing agent to the epoxy resin (equivalent of curing agent / equivalent of epoxy resin) is preferably in the range of 0.5 to 1.2, more preferably in the range of 0.7 to 1.1. More preferably, it is the range of 0.8-1.0. When the amount ratio (equivalent of curing agent / equivalent of epoxy resin) is within the above range, the obtained cured product tends to have high Tg and excellent heat resistance and UV resistance. In this specification, the equivalent is an equivalent based on the assumption that the acid anhydride group —CH ₂ —CO—O—CO—CH ₂ — and the glycidyl ring (epoxy ring) react one-on-one. Yes, 1 mol of acid anhydride group / 1 mol of glycidyl ring = equivalent ratio of 1.
In the epoxy resin composition of the present embodiment, the equivalent ratio of the curing agent to the epoxy resin (equivalent of curing agent / equivalent of epoxy resin) is equivalent to the equivalent of epoxy resin (epoxy equivalent) and the equivalent of curing agent (acid anhydride). Equivalents) can be measured and calculated from the measured values. The epoxy equivalent can be determined by measuring a potential difference with a 0.1 mol / L perchloric acid acetic acid standard solution according to JIS K7236. Furthermore, the acid anhydride equivalent can be determined by performing a component analysis using a nuclear magnetic resonance apparatus (NMR) or gas chromatography (GC) and calculating the result.

  The epoxy resin composition of the present embodiment includes a curing accelerator, an antioxidant, a UV absorber, an inorganic filler, a resin modifier, a silane coupling, as necessary, as long as the effects of the present invention are not impaired. You may contain various additives, such as an agent. These additives may be used alone or in combination of two or more.

Although it does not specifically limit as a hardening accelerator, For example, tertiary amines, such as benzyldimethylamine, a tris (dimethylaminomethyl) phenol, a dimethyl cyclohexylamine; 1-cyanoethyl-2-ethyl-4-methylimidazole, 2- Imidazoles such as ethyl-4-methylimidazole and 1-benzyl-2-methylimidazole; organophosphorus compounds such as triphenylphosphine and triphenyl phosphite; tetraphenylphosphonium bromide, tetra-n-butylphosphonium bromide and the like Quaternary phosphonium salts; diazabicycloalkenes such as 1,8-diazabicyclo [5.4.0] undecene-7 and organic acid salts thereof; organometallic compounds such as zinc octylate, tin octylate and aluminum acetylacetone complex Class: Tetraeth Ammonium bromide, quaternary ammonium salts such as tetrabutylammonium bromide; boron trifluoride, boron compounds such as triphenyl borate; zinc chloride, metal halides such as stannic chloride. Furthermore, high melting point imidazole compounds, dicyandiamide, high melting point dispersion type latent accelerators such as amine addition type accelerators with amines added to epoxy resins, etc., and imidazole, phosphorus and phosphine accelerators are coated with a polymer. Latent cure represented by high temperature dissociation type thermal cationic polymerization type latent cure accelerator such as microcapsule type latent accelerator, amine salt type latent cure accelerator, Lewis acid salt, Bronsted acid salt, etc. Accelerators can also be used. These curing accelerators can be used alone or in admixture of two or more.
In the epoxy resin composition of the present embodiment, the content of the curing accelerator is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and further preferably 0.1 to 10% by mass. 3% by mass.

The antioxidant can further improve the heat resistance stability of the resulting cured product. Although it does not specifically limit as antioxidant, For example, phenolic antioxidant (dibutylhydroxytoluene etc.), sulfur type antioxidant (mercaptopropionic acid derivative etc.), phosphorus antioxidant (9,10-dihydro-). 9-oxa-10-phosphaphenanthrene-10-oxide and the like. Among these, a phenolic antioxidant can be preferably used. These additives can be used individually or in mixture of 2 or more types.
In the epoxy resin composition of the present embodiment, the content of the antioxidant is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and still more preferably 0.1 to 10% by mass. 3% by mass.

Although it does not specifically limit as a UV absorber, For example, the benzotriazole type | system | group represented by TINUBIN P and TINUVIN234 by BASF; Triazine type | system | groups, such as TINUVIN 1577ED;
In the epoxy resin composition of the present embodiment, the content of the UV absorber is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and still more preferably 0.1 to 10% by mass. 3% by mass.

The inorganic filler is not particularly limited, and examples thereof include glass fiber, carbon fiber, titanium oxide, alumina, talc, mica, and aluminum hydroxide.
In the epoxy resin composition of the present embodiment, the content of the inorganic filler is preferably 0.01 to 80% by mass, more preferably 0.01 to 50% by mass, and still more preferably 0.1 to 80% by mass. 20% by mass.

The resin modifier is not particularly limited. For example, a diluent such as n-butyl glycidyl ether, phenyl glycidyl ether, glycidyl methacrylate, vinylcyclohexene dioxide, diglycidyl aniline, glycerin triglycidyl ether; polypropylene glycidyl ether, polymerization Examples include flexibility imparting agents such as fatty acid polyglycidyl ether, polypropylene glycol, and urethane prepolymer.
In the epoxy resin composition of the present embodiment, the content of the resin modifier is preferably 0.01 to 80% by mass, more preferably 0.01 to 50% by mass, and still more preferably 0.1. ˜20 mass%.

The silane coupling agent is not particularly limited, and examples thereof include chloropropyltrimethoxysilane, vinyltrichlorosilane, γ-methacryloxypropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.
In the epoxy resin composition of the present embodiment, the content of the silane coupling agent is preferably 0.01 to 20% by mass, more preferably 0.05 to 10% by mass, and still more preferably 0.1. ˜5 mass%.

  The curing method of the epoxy resin composition is not particularly limited, and for example, a conventionally known curing apparatus such as a closed curing furnace or a tunnel furnace capable of continuous curing can be employed. Although the heating method used for the said hardening is not specifically limited, For example, it can carry out by a conventionally well-known method, such as hot air circulation, infrared heating, high frequency heating.

  The curing temperature and curing time are preferably in the range of 80 ° C. to 250 ° C. and 30 seconds to 10 hours. When it is desired to reduce the internal stress of the cured product, after pre-curing under conditions of 80 ° C. to 120 ° C. and 0.5 hours to 5 hours, post-curing under conditions of 120 ° C. to 180 ° C. and 0.1 hours to 5 hours It is preferable to do. When aiming at short-time curing, curing is preferably performed under conditions of 150 ° C. to 250 ° C. and 30 seconds to 30 minutes.

  The epoxy resin composition of the present embodiment may be stored separately in two or more components, for example, a component containing an acid anhydride and a component containing an epoxy resin, and these may be prepared before curing. Moreover, the epoxy resin composition of this embodiment may be preserve | saved as a thermosetting composition which mix | blended each component, and you may use for hardening | curing as it is. When storing as a thermosetting composition, it is preferable to store at a low temperature (usually −40 ° C. to 15 ° C.).

[Hardened product, molded product]
The cured product of the present embodiment is obtained by curing the above-described epoxy resin composition. The curing method is as described above. The cured product according to the present embodiment uses the above-described epoxy resin curing agent to improve the performance of the epoxy resin and improve the surface hardness, UV color resistance, and glass transition point. For example, the cured product of this embodiment preferably has a pencil hardness of 3H or more, and the UV color resistance is preferably 450 hours or more when the light transmittance at 400 nm is reduced to 70%. The transition point is preferably 130 ° C. or higher.

  In particular, in the cured product of this embodiment, when an alicyclic epoxy resin is used as the main agent, the surface hardness and UV color resistance are significantly improved. Moreover, the cured | curing material of this embodiment has a remarkable improvement in a glass transition point, when using a BisA type epoxy resin as a main ingredient.

  The molded body of the present embodiment includes the above-described cured product. The molded body of the present embodiment is excellent in properties such as surface hardness and UV coloring resistance, and thus is suitably used for various applications.

  The epoxy resin composition, cured product or molded article of the present embodiment is suitably used for transparent member applications (adhesives, paints, LED sealing materials, transparent plates, etc.) taking advantage of the above-mentioned favorable characteristics.

  Next, the present invention will be described specifically by way of examples. However, this invention is not restrict | limited at all by these Examples.

The curing method and physical property measurement method of the epoxy resin composition are as follows.
<Curing method>
The epoxy resin compositions obtained in Examples and Comparative Examples described later were mixed in a beaker with a stirrer, and the dissolved inert gas in the epoxy resin composition was degassed in vacuum. Thereafter, the epoxy resin composition is poured into a silicone mold having a 50 mm square and a depth of 3 mm, precured in a hot air dryer at 120 ° C. for 3 hours, and further post-cured at 150 ° C. for 2 hours. A cured product was obtained.

<Measurement of glass transition point (Tg)>
The glass transition point (Tg) was measured using a thermal analysis system EXSTRA6000 TMA (thermomechanical measuring device) manufactured by Seiko Instruments Inc. Specifically, the sample was compressed and expanded from 30 ° C. to 260 ° C. at a first temperature increase rate of 10 ° C./min under a N ₂ air flow, and at a second temperature increase rate of 10 ° C./min, 30 ° C. The sample was measured by compressing and expanding from ˜330 ° C. Tg was calculated | required from the measurement result of the 2nd time.

<Pencil hardness measurement>
According to JIS K 5400, pencil hardness was measured using pencil scratching.

<UV coloring resistance test>
The UV coloring resistance test was performed by placing a cured product in a test furnace of Dainippon Plastics I Super UV Tester SUV-W11, under the condition of 55 ° C./50 RH%, and a wavelength range of 295 to 450 nm (360 The cured product was irradiated with light having a maximum intensity peak at ˜380 nm at an irradiation surface light intensity of 68 mW / cm ² .

<Light transmittance measurement>
The cured product before and after the UV coloring resistance test history was measured for light transmittance with a spectrophotometer [Spectrophotometer UV-3100 manufactured by Shimadzu Corporation]. Further, the refractive index of the cured product before and after the UV coloring resistance test history was measured with a multi-wavelength Abbe refractometer DR-M2 manufactured by Atago Co., Ltd. The light transmittance at 400 nm of the cured product corresponding to a thickness of 1 mm was determined from the measured light transmittance and the surface reflectance calculated from the separately measured refractive index. Further, the measurement was repeated, and the light transmittance at 400 nm of the cured product after the UV color resistance test history was 70% with respect to the light transmittance at 400 nm of the cured product before the UV color resistance test history. The irradiation time in the UV resistance test until the following was obtained.

Synthesis Example 1
(Preparation of dimethyladamantane maleic anhydride 1-adduct [DMMA] (epoxy resin curing agent))
A reaction vessel was charged with 1.6 mol of 1,3-dimethyladamantane and 1 mol of maleic anhydride, and the temperature in the reaction vessel was maintained at 160 ° C. A reaction solution in which 5.5 mmol of di-tert-butyl peroxide as a radical generator was dissolved in a small amount of 1,3-dimethyladamantane was dropped into the reaction vessel over 3 hours to carry out the reaction. The reaction was completed in 3 hours from the end of dropping to obtain a reaction product. The obtained reaction product was distilled under reduced pressure to obtain the corresponding target product (dimethyladamantane maleic anhydride 1-adduct). After completion of the reaction, the yield (GC yield) of the obtained dimethyladamantane maleic anhydride 1-adduct was 45 mol% (maleic anhydride basis). In Examples and Comparative Examples described later, the obtained dimethyladamantane maleic anhydride 1-adduct was used as an epoxy resin curing agent.
Incidentally, the obtained dimethyl adamantane maleic anhydride 1 adduct, nuclear magnetic resonance spectra ⁽¹ H-NMR, JEOL Ltd., 100 MHz) were identified by. The identification results are shown below.
¹ H-NMR (CCl ₄ / TMS) δ 0.85 (s, 6H, CH ₃ ); 1.1-1.7 (m, 13H); 2.0-2.7 (m, 3H, CH ₂₎ , CH)

Synthesis Example 2
(Preparation of monoethyladamantane maleic anhydride 1 adduct [ETAMA] (epoxy resin curing agent))
A reaction vessel was charged with 1.6 mol of 1-ethyladamantane and 1 mol of maleic anhydride, and the temperature in the reaction vessel was maintained at 160 ° C. A reaction solution in which 5.5 mmol of di-tert-butyl peroxide as a radical generator was dissolved in a small amount of 1-ethyladamantane was dropped into the reaction vessel over 3 hours to carry out the reaction. The reaction was completed in 3 hours from the end of dropping to obtain a reaction product. The obtained reaction product was distilled under reduced pressure to obtain the corresponding target product (monoethyladamantane maleic anhydride 1-adduct). After completion of the reaction, the obtained ethyladamantane maleic anhydride monoadduct had a GC yield of 63 mol% (maleic anhydride basis). In the examples and comparative examples described later, the obtained ethyladamantane maleic anhydride monoadduct was used as an epoxy resin curing agent.
Incidentally, the resulting monoethyl adamantane maleic anhydride 1 adduct, nuclear magnetic resonance spectra ⁽¹ H-NMR, JEOL Ltd., 100 MHz) were identified by. The identification results are shown below.
¹ H-NMR (CCl ₄ / TMS) δ 0.90 (t, 3H, CH ₃ ); 1.1-1.7 (m, 16H); 2.0-2.7 (m, 3H, CH ₂ , CH)

Example 1
(DMAMA / BisA type epoxy resin)
35.1 parts by mass of dimethyladamantane maleic anhydride 1 adduct (DMAMA) prepared in Synthesis Example 1 above, 27.7 parts by mass of BisA type epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER828), A resin composition obtained by mixing 0.146 parts by mass of phosphonium bromide grade (San Apro Co., Ltd., U-CAT5003) and 0.509 parts by mass of phenolic antioxidant AO-50 (manufactured by ADEKA Co., Ltd.) Product (equivalent of curing agent / equivalent of epoxy resin = 0.90). A cured product was obtained by the above-described curing method using the obtained resin composition.
The Tg of the obtained cured product was 138 ° C.

Comparative Example 1
(MH700G / BisA type epoxy resin)
30.0 parts by mass of a mixture of hexahydrophthalic anhydride and methylhexahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., MH700G) and BisA type epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER828) 37.2 Part by mass, quaternary phosphonium bromide (manufactured by San Apro Co., Ltd., U-CAT5003) 0.197 part by mass, phenolic antioxidant AO-50 (manufactured by ADEKA Co., Ltd.) 0.544 parts by mass, Were mixed to obtain a resin composition (equivalent of curing agent / equivalent of epoxy resin = 0.90). A cured product was obtained by the above-described curing method using the obtained resin composition.
The obtained cured product had a Tg of 122 ° C.

Example 2
(DMMA / alicyclic epoxy resin)
42.0 parts by mass of dimethyladamantane maleic anhydride 1-adduct (DMAMA) prepared in Synthesis Example 1 and an alicyclic epoxy resin (3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate) : Daicel Chemical Industries, Ltd., CEL2021P) 22.5 parts by mass, quaternary phosphonium bromide (San Apro Co., Ltd., U-CAT5003) 0.175 parts by mass, and phenolic antioxidant AO-50 0.526 parts by weight (manufactured by ADEKA) was mixed to obtain a resin composition (equivalent of curing agent / equivalent of epoxy resin = 0.90). A cured product was obtained by the above-described curing method using the obtained resin composition.
When the UV color resistance test of the obtained cured product was performed, the irradiation time until the light transmittance at 400 nm of the cured product became 70% or less was 450 hours.
Moreover, the pencil hardness of the obtained cured product was 3H.

Example 3
(ETAMA / alicyclic epoxy resin)
25.4 parts by mass of monoethyladamantane maleic anhydride 1-adduct (ETAMA) prepared in Synthesis Example 2 and an alicyclic epoxy resin (3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxyl) Rate: 13.6 parts by mass of Daicel Chemical Industries, Ltd., CEL2021P), 0.110 parts by mass of quaternary phosphonium bromide (manufactured by San Apro Co., Ltd., U-CAT5003), and phenolic antioxidant AO-50 A resin composition (equivalent of curing agent / equivalent of epoxy resin = 0.90) was obtained by mixing 0.313 parts by mass (manufactured by ADEKA Corporation). A cured product was obtained by the above-described curing method using the obtained resin composition.
When the UV color resistance test of the obtained cured product was performed, the irradiation time until the light transmittance at 400 nm of the cured product reached 70% was 460 hours.
Moreover, the pencil hardness of the obtained cured product was 3H.

Comparative Example 2
(MH700G / alicyclic epoxy resin)
36.0 parts by mass of a mixture of hexahydrophthalic anhydride and methylhexahydrophthalic anhydride (MH700G, manufactured by Shin Nippon Rika Co., Ltd.) and an alicyclic epoxy resin (3,4-epoxycyclohexylmethyl-3 ′, 4 ′ -Epoxycyclohexanecarboxylate: Daicel Chemical Industries, Ltd., CEL2021P) 30.0 parts by mass, quaternary phosphonium bromide (San Apro Co., Ltd., U-CAT5003) 0.229 parts by weight, phenolic antioxidant Agent AO-50 (manufactured by ADEKA) 0.534 parts by mass was mixed to obtain a resin composition (equivalent of curing agent / equivalent of epoxy resin = 0.90). A cured product was obtained by the above-described curing operation method using the obtained resin composition.
When the UV resistance test of the obtained cured product was carried out, the irradiation time until the light transmittance at 400 nm of the cured product reached 70% was 220 hours. The irradiation time was about half that in Example 2.
Moreover, the pencil hardness of the obtained cured product was 2H.

  By using the epoxy resin composition containing the epoxy resin curing agent of the present invention, it is possible to obtain a cured product exhibiting high surface hardness, excellent UV coloring resistance, and high Tg. Moreover, this hardened | cured material can be applied suitably in field | areas, such as a LED sealing material use, an adhesive agent use, and a coating-material use.

Claims (8)

An epoxy resin, an epoxy resin curing agent comprising a compound represented by the following formula (1) seen including,
An epoxy resin composition, wherein the epoxy resin is at least one selected from the group consisting of an alicyclic epoxy resin, a nuclear hydrogenated BisA type diglycidyl ether, and a BisA type diglycidyl ether .
(In Formula (1), R shows a methyl group, an ethyl group, or a hydroxyl group, and n is an integer of 1-3.) Epoxy resin composition according to claim 1, wherein 0.5 to 1.2 (equivalent weight of equivalent / epoxy resin curing agent) equivalent ratio of the curing agent for said epoxy resin. The epoxy resin composition according to claim 1 or 2 , further comprising a curing accelerator. The epoxy resin composition according to any one of claims 1 to 3 , further comprising an antioxidant. The epoxy resin composition according to any one of claims 1 to 4 , further comprising a UV absorber. The epoxy resin composition according to any one of claims 1 to 5 , further comprising an inorganic filler. Cured product obtained by curing the resin composition according to any one of claims 1 to 6. The molded object containing the hardened | cured material of Claim 7 .