JP2009215329A - Energy ray-curable resin composition, adhesive using the same, and cured form - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: an energy ray-curable resin composition capable of satisfying adhesion, heat resistance, low moisture permeability and low curing-constractility in an advantageous balance and having excellent storage stability; an adhesive and a cured body using the same. <P>SOLUTION: This energy ray-curable resin composition comprises (A) an alicyclic epoxy compound, (B) silica particles having a uranium content of 1 ppb or less, (C) a photopolymerization initiator for cationic polymerization, and (D) a silane coupling agent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an energy ray curable resin composition, an adhesive using the same, and a cured product.

In recent years, in the field of electronics, with the improvement in performance of devices, display components such as liquid crystals and organic electroluminescence (hereinafter referred to as organic EL), electronic components such as image sensors such as CCD and CMOS, and semiconductor components, etc. In the bonding of element packages and the like to be used, an adhesive capable of bonding a small area of 1 cm ² or less and a thin film of 20 to 100 μm or less is required.

  On the other hand, contrary to the reduction in bonding area and bonding thickness, the properties required of adhesives are exposed to high adhesion strength to various adherends such as glass, ceramics, resins, and high temperatures such as 250 ° C. In the solder reflow process, the required level is increasing year by year, such as high heat resistance that does not cause peeling, and low moisture permeability that prevents element damage even under exposure to a high-temperature and high-humidity atmosphere. Furthermore, it is desirable to develop adhesives that have low cure shrinkage and low adhesive distortion so that internal stress due to cure shrinkage does not affect each package material, and that have excellent storage stability that can be stored for long periods at room temperature. ing.

  In this trend of technology, thermosetting epoxy adhesives, silicone adhesives, polyimide adhesives, etc. with excellent heat resistance are used as adhesives in this field. In view of the above, there is a demand for energy ray-curable adhesives such as ultraviolet rays having fast curing properties that replace conventional thermosetting types.

The energy ray curable epoxy adhesive has low curing shrinkage and is excellent in adhesion to various adherends, heat resistance, and moisture permeability. Patent Document 1 discloses an adhesive for lamination, Patent Document 2 Describes an adhesive for polyolefins, Patent Document 3 describes alkali glass, adhesive for metal bonding, Patent Document 4 describes an adhesive for CCD, and Patent Document 5 describes an adhesive for sealing an organic EL element. It is used in each field.
Japanese Patent Laid-Open No. 8-231938 JP 2001-131516 A JP 2003-327785 A JP 2004-269554 A JP 2006-169540 A

  However, the above-mentioned known adhesives satisfy the properties required in the recent electronics field, particularly heat resistance, low moisture permeability, low curing shrinkage, and storage stability that can be stored at room temperature for a long time. There is nothing to do.

  That is, the object of the present invention is to provide an energy beam having a small area and a high degree of demand for thin film bonding, adhesiveness, heat resistance, low moisture permeability, low curing shrinkage, and storage stability that can be stored for a long time at room temperature. It is to provide a curable resin composition, and an adhesive and a cured body using the same.

  According to the present invention, (A) an alicyclic epoxy compound, (B) silica particles having a uranium content of 1 ppb or less, (C) a photocationic polymerization initiator, and (D) a silane coupling agent are included. An energy ray curable resin composition is provided.

  The energy ray-curable resin composition having the above structure can satisfy the adhesiveness, heat resistance, low moisture permeability, and low curing shrinkage in a well-balanced manner and has excellent storage stability.

  According to the present invention, an energy ray-curable resin composition that can satisfy a good balance of adhesiveness, heat resistance, low moisture permeability, and low curing shrinkage and has excellent storage stability and an adhesive using the same And a cured product.

<Explanation of terms>
In the present specification, the energy ray curable resin composition means a resin composition that can be cured by irradiation with energy rays. Here, the energy rays mean energy rays typified by ultraviolet rays and visible rays.

In the present specification, the elastic retention rate R of the cured body of the resin composition is defined by the following equation, where Ea is a storage elastic modulus of about 25 ° C. and Eb is a storage elastic modulus of about 250 ° C.
R = Eb / Ea

  The storage elastic modulus is the real part of the complex elastic modulus, and means the magnitude of the in-phase stress component when a sinusoidal strain is applied to the viscoelastic body. Here, the complex elastic modulus means a value obtained by calculating a complex number as a vector in the ratio of maximum stress to maximum strain in dynamic viscoelasticity. Dynamic viscoelasticity refers to the behavior of a combination of viscosity and elasticity when a constant sinusoidal strain is applied to a material. This is obtained by measuring stress against strain or strain against stress.

  The storage elastic modulus is preferably measured using a known dynamic viscoelasticity spectrum meter (for example, DMS series manufactured by SII Nanotechnology, RSA series manufactured by TA Instruments) or the like.

  In the present specification, the symbol “to” means “above” and “below”. For example, “A to B” means not less than A and not more than B.

  Hereinafter, embodiments of the present invention will be described in detail.

  The energy ray-curable resin composition according to this embodiment includes (A) an alicyclic epoxy compound, (B) silica particles having a uranium content of 1 ppb or less, (C) a photocationic polymerization initiator, and (D) a silane coupling agent. It is characterized by containing.

  The energy ray-curable resin composition having the above structure can satisfy the adhesiveness, heat resistance, low moisture permeability, and low curing shrinkage in a well-balanced manner and has excellent storage stability.

  Next, components of the energy beam curable resin composition according to the present embodiment will be described.

((A) Alicyclic epoxy compound)
The energy beam curable resin composition according to the present embodiment includes (A) an alicyclic epoxy compound as an essential component. By using an alicyclic epoxy compound, the energy ray-curable resin composition according to the present embodiment exhibits excellent adhesiveness and heat resistance.

  (A) As an alicyclic epoxy compound, a compound having at least one cyclohexene or cycloalkane ring such as cyclopentene ring or pinene ring is epoxidized with an appropriate oxidizing agent such as hydrogen peroxide or peracid. And hydrogenated epoxy compounds obtained by hydrogenating aromatic epoxy compounds such as bisphenol A type epoxy compounds. These compounds or derivatives may be used alone or in combination of two or more.

  Here, in particular, an alicyclic epoxy compound containing one or more epoxy groups and one or more ester groups in one molecule is preferable. Such an alicyclic epoxy compound is preferable because of excellent heat resistance due to interaction between ester groups or ester groups and silica particles having a uranium content of 1 ppb or less, which is the component (B).

  Examples of such alicyclic epoxy compounds include, but are not limited to, 3,4-epoxycyclohexenylmethyl-3 ', 4'-epoxycyclohexenecarboxylate, 3,4-epoxycyclohexylmethyl methacrylate, and the like.

((B) Silica particles having a uranium content of 1 ppb or less)
The energy beam curable resin composition according to the present embodiment includes (B) silica particles having a uranium content of 1 ppb or less as an essential component. (B) By using silica particles having a uranium content of 1 ppb or less, the energy ray-curable resin composition according to the present embodiment exhibits low moisture permeability and low cure shrinkage, and (A) is an alicyclic compound. Excellent heat resistance when used in combination with epoxy resin. Furthermore, since the uranium content is 1 ppb or less, it is possible to provide an energy ray curable composition having excellent storage stability that can be stored at room temperature for a long time, which was difficult with conventional silica particles, and an adhesive using the same.

Here, the silica particle is a silica particle having a purity of 99% or more represented by SiO _X (1 ≦ X ≦ 2) as a chemical composition, and a low uranium silica particle having a uranium content of 1 ppb or less. To tell.

  The method for synthesizing the low uranium silica particles is not particularly limited, but a method of neutralizing alkali silicate, gel drying, flame melting after pulverization, flame decomposition of alkoxysilane, and volatile silicon compounds such as silicon tetrachloride. Examples thereof include a method of hydrolyzing gas phase and a method of pulverizing and melting low uranium quartz. These methods are preferable because stable low uranium silica particles can be easily obtained.

  Examples of the method for measuring the uranium content include a measurement method using a spectrofluorometer (for example, a measurement limit of 0.01 ppb, manufactured by Hitachi Keiki Co., Ltd.).

  (B) Silica particles having a uranium content of 1 ppb or less are preferably contained at a ratio of 150 parts by mass or more and 400 parts by mass or less with respect to 100 parts by mass of (A) the alicyclic epoxy compound. If it is 150 parts by mass or more, low curing shrinkage can be obtained, and if it is 400 parts by mass or less, the adhesiveness is not lowered.

  (B) The particle diameter of silica particles having a uranium content of 1 ppb or less is such that the 50% particle diameter is in the range of 0.1 μm to 15 μm, and the 90% particle diameter is in the range of 50% particle diameter to 20 μm. preferable. If the 50% particle size is in the range of 0.1 μm or more and 15 μm or less, and the 90% particle size is in the range of 50% or more and 20 μm or less, the particle size is too small to easily aggregate. The particle size is too large to easily settle.

  The 50% particle diameter and 90% particle diameter here refer to the particle diameter when the volume cumulative frequency is 50% and 90%.

  The method for measuring the particle size is not particularly limited, and examples thereof include a laser diffraction particle size distribution meter, a laser Doppler particle size distribution meter, a dynamic light scattering particle size distribution meter, and an ultrasonic particle size distribution meter.

  (B) The shape of the silica particles having a uranium content of 1 ppb or less includes, for example, a crushed shape, a spherical shape, and the like, and is not particularly limited, but is a spherical shape that can be highly filled and has no sharp corners that may damage the device. Silica particles are preferably used.

  Further, (B) silica particles having a uranium content of 1 ppb or less preferably have a surface hydroxyl group content in the range of 3 to 20 particles / nm. If it is 3 pieces / nm or more, the silane coupling agent is favorably adsorbed on the surface, so that the dispersibility is improved. As a result, suitable adhesiveness can be obtained. They do not easily aggregate and storage stability does not deteriorate.

((C) Photocationic polymerization initiator)
The energy beam curable resin composition according to the present embodiment contains (C) a photocationic polymerization initiator. By using a cationic photopolymerization initiator, the energy ray-curable resin composition according to this embodiment can be cured by irradiation with energy rays such as ultraviolet rays.

  (C) As the cationic photopolymerization initiator, arylsulfonium salt derivatives (for example, Cyracure UVI-6990, Cyracure UVI-6974, manufactured by Dow Chemical Company, Adekaoptomer SP-150, Adekaoptomer SP, manufactured by Asahi Denka Kogyo Co., Ltd.) -152, Adekaoptomer SP-170, Adekaoptomer SP-172, CPI-100P, CPI-101A, CPI-200K, CPI-210S, Ciba-Cure 1190 manufactured by Double Bond, etc.), aryliodonium salt derivatives (For example, Irgacure 250 manufactured by Ciba Specialty Chemicals, RP-2074 manufactured by Rhodia Japan), acid generators such as allene-ion complex derivatives, diazonium salt derivatives, triazine initiators and other halides. Et That. These photocationic polymerization initiators may be used alone or in combination of two or more.

  (C) Although it does not specifically limit as anion seed | species of a photocationic polymerization initiator, For example, halides, such as a boron compound, a phosphorus compound, an antimony compound, an arsenic compound, and an alkylsulfonic acid compound, are mentioned. Further, fluoride is preferable from the viewpoint of good UV curability and, as a result, improved adhesion, heat resistance and low moisture permeability.

  (C) It is preferable to contain a photocationic polymerization initiator in the ratio of 0.1-5 mass parts with respect to 100 mass parts of (A) alicyclic epoxy compounds. If the content of the cationic photopolymerization initiator is 0.1 parts by mass or more, the curability is not deteriorated, and if it is 5 parts by mass or less, the heat resistance is not lowered.

  Moreover, in order to improve the sensitivity of the (C) photocationic polymerization initiator, various photosensitizers may be used in combination.

  Although it does not specifically limit as a photosensitizer, For example, a thioxanthone derivative, a benzophenone derivative, a phenothiazine derivative, a phenyl ketone derivative etc. are mentioned. However, it is not limited to these, and a known photosensitizer can be applied.

((D) Silane coupling agent)
Moreover, the energy beam curable resin composition which concerns on this embodiment contains (D) silane coupling agent. By using a silane coupling agent, the energy ray-curable resin composition according to the present embodiment further exhibits excellent heat resistance and storage stability.

  (D) As a silane coupling agent, γ-chloropropyltrimethoxysilane, vinyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyl-tris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxy Silane, γ-acryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxy Silane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-ureidopropyltriethoxysilane and the like are preferable, Is β- ( 3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane and the like. These silane coupling agents may be used alone or in combination of two or more.

  (D) It is preferable to contain a silane coupling agent in the ratio of 0.1-10 mass parts with respect to 100 mass parts of (A) alicyclic epoxy compounds. If the content of the silane coupling agent is 0.1 parts by mass or more, suitable dispersibility can be obtained, and if it is 10 parts by mass or less, the adhesiveness is not lowered.

(Cationically polymerizable compound)
The energy beam curable resin composition according to this embodiment may further contain other cationically polymerizable compounds such as an aromatic epoxy compound, an aliphatic epoxy compound, an oxetane compound, and a vinyl ether compound. By containing these, the viscosity and hardness can be adjusted.

  Here, as the aromatic epoxy compound, any of a monomer, an oligomer or a polymer can be used. Although it does not specifically limit as an aromatic epoxy compound, For example, bisphenol A type epoxy compound, bisphenol F type epoxy compound, bisphenol S type epoxy compound, biphenyl type epoxy compound, fluorene type epoxy compound, novolak phenol type epoxy compound, cresol novolak Type epoxy compounds or modified products thereof.

  Although it does not specifically limit as an aliphatic epoxy compound, For example, di or polyglycidyl ether of aliphatic polyhydric alcohol or its alkylene oxide adduct etc. are mentioned. Examples of the aliphatic epoxy compound include diglycidyl ether of ethylene glycol, diglycidyl ether of propylene glycol or diglycidyl ether of 1,6-hexanediol, diglycidyl ether of alkylene glycol, glycerin or its alkylene oxide adduct di- or Polyglycidyl ether of polyhydric alcohol such as triglycidyl ether, diglycidyl ether of polyethylene glycol or its alkylene oxide adduct, diglycidyl ether of polyalkylene glycol such as diglycidyl ether of polypropylene glycol or its alkylene oxide adduct, etc. It is done. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  The oxetane compound is not particularly limited. For example, 3-ethyl-3-hydroxymethyloxetane (trade name OXT101 manufactured by Toa Gosei Co., Ltd.), 1,4-bis [(3-ethyl-3-oxetanyl) methoxy Methyl] benzene (same as OX121), 3-ethyl-3- (phenoxymethyl) oxetane (same as OXT211), di (1-ethyl-3-oxetanyl) methyl ether (same as OXT221), 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane (such as OXT212) and the like. This oxetane compound is a compound having one or more oxetane rings in the molecule.

  Although it does not specifically limit as a vinyl ether compound, For example, ethylene glycol divinyl ether, ethylene glycol monovinyl ether, diethylene glycol divinyl ether, triethylene glycol monovinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butane Di- or trivinyl ether compounds such as diol divinyl ether, hexanediol divinyl ether, cyclohexane dimethanol divinyl ether, hydroxyethyl monovinyl ether, hydroxynonyl monovinyl ether, trimethylolpropane trivinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, Tadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl ether-o-propylene carbonate, dodecyl vinyl ether, diethylene glycol monovinyl ether, octadecyl vinyl ether, etc. And monovinyl ether compounds.

(Inorganic filler)
The energy beam curable resin composition according to the present embodiment may further contain an inorganic filler.

  Examples of inorganic fillers include glass fillers, spherical alumina, crushed alumina, oxides such as magnesium oxide, beryllium oxide and titanium oxide, nitrides such as boron nitride, silicon nitride and aluminum nitride, carbides such as silicon carbide, Examples thereof include hydroxides such as aluminum hydroxide and magnesium hydroxide, metals and alloys such as copper, silver, iron, aluminum, nickel and titanium, and carbon-based fillers such as diamond and carbon. By containing these inorganic fillers, the heat radiation property of the energy beam curable resin composition is improved, which is preferable.

  In addition, the energy ray curable resin composition according to the present embodiment includes various elastomers such as acrylic rubber and urethane rubber, a methyl methacrylate-butadiene-styrene graft copolymer, and the like within a range that does not impair the purpose of the present embodiment. Use additives such as acrylonitrile-butadiene-styrene graft copolymers, solvents, fillers, reinforcing materials, plasticizers, thickeners, dyes, pigments, flame retardants and surfactants. Can do.

  The energy ray-curable resin composition having the above-described configuration may be cured by irradiation with energy rays to form a cured body.

  Moreover, you may use the energy-beam curable resin composition which consists of the said structure as an adhesive agent. This adhesive can be preferably used for bonding display components such as liquid crystal and organic EL, electronic components such as image sensors such as CCD and CMOS, and element packages used for semiconductor components.

The adhesive can be used for adhesion of the above components because it can be adhered to a minute area having an area of 1 cm ² or less, and further to a thin film having a thickness of 5 μm to 100 μm.

[Production method]
About the manufacturing method of the energy beam curable resin composition which concerns on this embodiment, if said material can fully be mixed, there will be no restriction | limiting in particular. The mixing method of the material is not particularly limited, but for example, a normal dispersing machine such as a stirring method using a stirring force accompanying rotation of a propeller, a roll kneading method and a sand mill, a planetary stirrer by rotation and revolution, etc. Can be mentioned. These mixing methods are preferable because stable mixing can be performed at low cost.

  After performing the above mixing, the energy ray curable resin composition may be cured by irradiation with energy rays using the following light source.

(light source)
In the present embodiment, the light source used for curing and adhering the energy beam curable resin composition is not particularly limited. For example, a halogen lamp, a metal halide lamp, a high-power metal halide lamp (containing indium, etc.), low-pressure mercury Lamp, high pressure mercury lamp, ultra high pressure mercury lamp, xenon lamp, xenon excimer lamp, xenon flash lamp, light emitting diode (hereinafter referred to as LED), and the like. These light sources are preferable because they can efficiently irradiate energy rays corresponding to the reaction wavelength of each photopolymerization initiator.

  Each of the light sources has a different emission wavelength and energy distribution. Therefore, the light source is appropriately selected depending on the reaction wavelength of the photopolymerization initiator. Natural light (sunlight) can also be a reaction initiation light source.

  The light source may perform direct irradiation, condensing irradiation using a reflecting mirror, or condensing irradiation using a fiber or the like. Moreover, a low wavelength cut filter, a heat ray cut filter, a cold mirror, etc. can also be used.

<Effect>

  The energy ray curable resin composition having the above-described configuration can satisfy the balance of adhesiveness, heat resistance, low moisture permeability, and low cure shrinkage, and has an excellent storage stability. And an adhesive using the same.

  When the energy ray curable resin composition is 100 parts by mass of the component (A), the component (B) is 150 to 400 parts by mass, the component (C) is 0.1 to 5 parts by mass, and the component (D). It is preferable to contain 0.1-10 mass parts. Thereby, adhesiveness, heat resistance, low moisture permeability, low curing shrinkage and storage stability can be further improved.

  In the energy ray curable resin composition, (B) 50% particle size of silica particles having a uranium content of 1 ppb or less is in the range of 0.1 μm to 15 μm, and 90% particle size is 50% particle size to 20 μm. The following range is preferable. Thereby, the particle diameter is not too small to easily aggregate, and the particle diameter is not too large to easily settle.

  In the energy beam curable resin composition, the (A) alicyclic epoxy compound preferably contains one or more epoxy groups and one or more ester groups in the molecule. Thereby, the energy beam curable resin composition which is excellent in heat resistance by the interaction between ester groups or ester groups and silica particles having a uranium content of 1 ppb or less as the component (B) is obtained.

  Moreover, it is preferable that the elasticity maintenance factor R of the hardening body of the said energy-beam curable resin composition is 0.10 or more. Thereby, it can be used as an adhesive excellent in heat resistance that does not cause peeling even in a solder reflow process exposed to a high temperature of about 250 ° C.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

In the examples and comparative examples, the following compounds were used.
The following was used as the alicyclic epoxy compound of component (A).
(A-1) 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexene carboxylate (“Celoxide 2021P” manufactured by Daicel Chemical Industries)
(A-2) 3,4-epoxycyclohexenylmethyl methacrylate ("Cyclomer M-100" manufactured by Daicel Chemical Industries)

Moreover, the following was used as an epoxy compound for a comparison.
(A-3) Liquid bisphenol A type epoxy resin (“ADEKA OPTMER KRM-2410” manufactured by ADEKA)

The following were used as silica particles having a uranium content of 1 ppb or less as the component (B). The shape, uranium content, 50% particle size, and 90% particle size are shown in Table 1.
(B-1) Denka fused silica FB-5SDX (manufactured by Denki Kagaku Kogyo Co., Ltd.)
(B-2) Denka fused silica FB-3SDX (manufactured by Denki Kagaku Kogyo Co., Ltd.)
(B-3) Denka fused silica FB-1SDX (manufactured by Denki Kagaku Kogyo Co., Ltd.)

Moreover, the following was used as a silica particle for a comparison.
(B-4) Denka fused silica FB-5D (manufactured by Denki Kagaku Kogyo Co., Ltd.)
(B-5) Denka fused silica FS-44 (manufactured by Denki Kagaku Kogyo Co., Ltd.)

The following was used as the photocationic polymerization initiator of component (C).
(C-1) Triarylsulfonium salt hexafluoroantimonate (“ADEKA OPTMER SP-170” manufactured by ADEKA)

The following was used as the silane coupling agent of component (D).
(D-1) γ-Glycidoxypropyltrimethoxysilane (“KBM-403” manufactured by Shin-Etsu Silicone)

  The raw materials of the types shown in Tables 2 and 3 were mixed at the composition ratios shown in Tables 2 and 3, and resin compositions of Examples 1 to 5 and Comparative Examples 1 to 6 were prepared.

  The following measurements were performed on the resin compositions of Examples and Comparative Examples. The results are shown in Tables 2 and 3.

[Evaluation of storage stability]
The resin composition is allowed to stand in an environment with a temperature of 25 ° C. in a light-shielding plastic container, and the viscosity is measured over time. Those that could not be measured due to, for example, were evaluated as x. The viscosity was measured at a rotational speed of 20 rpm using a B-type viscometer in an environment of 25 ° C.

[Evaluation of photocurability]
When the resin composition was photocured, it was cured under the following conditions.
It hardened | cured on the conditions of the integrated light quantity of 4,000 mJ / cm < ² > of the wavelength of 365 nm with the UV hardening apparatus (made by Fusion company) mounted with an electrodeless discharge metal halide lamp.

[Evaluation of curing shrinkage]
The resin composition was cured under the above-mentioned photocuring conditions to prepare a cured product sample, and the density (value is K) of this cured product at 23 ° C. was measured in accordance with A method of JIS K7112. On the other hand, the density (value is L) of the liquid of the resin composition before curing at 23 ° C. was measured using a specific gravity bottle in accordance with JIS K 6833. From the density values of the obtained cured product and resin composition liquid, the cure shrinkage rate (%) was calculated by the following formula.
Curing shrinkage (%) = (KL) / K × 100

[Evaluation of moisture permeability]
A sheet-like adhesive cured body having a thickness of 0.1 mm was prepared under the above-mentioned photocuring conditions, and calcium chloride (anhydrous) as a hygroscopic agent in accordance with JIS Z0208 “Method of testing moisture permeability of moisture-proof packaging material (cup method)” Was used under the conditions of an atmospheric temperature of 60 ° C. and a relative humidity of 90%.

[Evaluation of elastic retention ratio R]
Prepare a 5 mm x 50 mm x 1 mm adhesive cured body under the above-mentioned photocuring conditions, and set it with a dynamic viscoelasticity spectrum meter (DMS-210 manufactured by SII Nanotechnology) with a distance between chucks of 20 mm. The frequency was 1 Hz, the heating rate was 2 ° C./min, and the tensile mode was used. At this time, the storage elastic modulus at about 25 ° C. was Ea, the storage elastic modulus at about 250 ° C. was Eb, and the elastic retention rate R defined by the following formula was calculated.
R = Eb / Ea

[Evaluation of tensile shear bond strength]
Using two borosilicate glass test pieces “25 × 25 × 2.0 mm thickness, Tempax (registered trademark)”, the adhesive was cured under the above-mentioned photocuring conditions with an adhesive area of 0.5 cm ² and an adhesive thickness of 80 μm. . After curing, using a test piece bonded with an adhesive, the tensile shear bond strength (unit: MPa) was measured at an elongation of 10 mm / min in an environment of a temperature of 23 ° C. and a relative humidity of 50%.

[Evaluation of adhesive heat resistance]
Using two borosilicate glass test pieces “25 × 25 × 2.0 mm thickness, Tempax (registered trademark)”, the adhesive was cured under the above-mentioned photocuring conditions with an adhesive area of 0.5 cm ² and an adhesive thickness of 80 μm. . After curing, a test piece bonded with an adhesive was used and exposed to an environment of about 250 ° C. for 10 minutes, and changes in the adhesive before and after the exposure were observed. Those with little change were evaluated as ○, and those with changes such as peeling, void generation, interference fringe generation were evaluated as x.

<Discussion>

  It turns out that the energy-beam curable resin composition of Examples 1-5 which concerns on this invention has adhesiveness, heat resistance, low moisture permeability, low cure shrinkage, and storage stability in good balance. This will be described below.

  First, as can be seen from Table 2, the energy ray curable resin compositions of Examples 1 to 5 are excellent in storage stability, and change in viscosity is small even after storage for 7 days. This is probably because the uranium content of the silica particles is 1 ppb or less.

  In addition, the energy ray curable resin compositions of Examples 1 to 5 have a small cure shrinkage rate, and in Example 2, almost no shrinkage occurs. And the energy-beam curable resin composition of Examples 1-5 has low moisture permeability. This is probably because silica particles having a uranium content of 1 ppb or less are blended.

  Furthermore, it turns out that the energy-beam curable resin composition of Examples 1-5 has little change also in a high temperature environment, and adhesive heat resistance is good. This is thought to be due to the use of an alicyclic epoxy compound.

  Moreover, the energy beam curable resin compositions of Examples 1 to 5 have sufficient adhesive strength of 18 MPa or more while having the above characteristics.

  In contrast to the experimental results of Examples 1 to 5 as described above, the results of Comparative Examples 1 to 6 were as follows.

  In Comparative Examples 1 and 2, the storage stability was poor and measurement was impossible. Moreover, in Comparative Example 3, the adhesion heat resistance was low, and peeling and voids occurred. Moreover, in the comparative example 4, it turns out that a cure shrinkage rate is high and a water vapor transmission rate is high. In Comparative Example 5, the resin composition is not cured. This is probably because no photocationic polymerization initiator was added. In Comparative Example 6, the storage stability is poor and the adhesion heat resistance is low. This is considered to be because the silane coupling agent is not blended.

  As can be seen from the above experimental results, the energy ray curable resin composition according to the present invention can satisfy a good balance of adhesiveness, heat resistance, low moisture permeability, and low curing shrinkage, and has excellent storage stability. Have

  As described above, according to the present invention, (A) an alicyclic epoxy compound, (B) silica particles having a uranium content of 1 ppb or less, (C) a photocationic polymerization initiator, and (D) a silane coupling agent are contained. An energy beam curable resin composition is provided. The energy ray-curable resin composition having the above structure can satisfy the adhesiveness, heat resistance, low moisture permeability, and low curing shrinkage in a well-balanced manner and has excellent storage stability.

Claims (7)

An energy ray-curable resin composition comprising (A) an alicyclic epoxy compound, (B) silica particles having a uranium content of 1 ppb or less, (C) a cationic photopolymerization initiator, and (D) a silane coupling agent. object. When the component (A) is 100 parts by mass, the component (B) is 150 to 400 parts by mass, the component (C) is 0.1 to 5 parts by mass, and the component (D) is 0.1 to 10 parts. The energy ray-curable resin composition according to claim 1, further comprising: (B) The silica particles having a uranium content of 1 ppb or less have a 50% particle size in the range of 0.1 to 15 μm, and a 90% particle size in the range of 50 to 20 μm. The energy beam curable resin composition according to claim 1. The energy ray curable according to any one of claims 1 to 3, wherein the (A) alicyclic epoxy compound contains one or more epoxy groups and one or more ester groups in the molecule. Resin composition. 5. The energy ray-curable resin composition according to claim 1, wherein the elastic body has an elastic retention ratio R of 0.10 or more by curing the energy ray-curable resin composition. . The hardening body formed by hardening | curing the said energy-beam curable resin composition in any one of Claims 1-5. The adhesive agent which consists of the said energy-beam curable resin composition in any one of Claims 1-5.