KR20120103433A - Energy ray-curable epoxy resin composition having excellent curing properties in deep portions - Google Patents

Abstract

In an energy ray hardening type epoxy resin composition, it solves the problem that core part hardening property is bad, maintaining high fixing precision. An energy ray curable epoxy resin composition comprising an epoxy resin, a filler, and a photoacid generator, wherein the difference between the refractive index of the filler and the refractive index of the energy ray curable epoxy resin composition not containing the filler is within ± 0.02. It is about.

Description

ENERGY RAY-CURABLE EPOXY RESIN COMPOSITION HAVING EXCELLENT CURING PROPERTIES IN DEEP PORTIONS}

The present invention relates to an energy ray-curable epoxy resin composition, and in particular, to an energy ray-curable epoxy resin composition for fixing an optical component having excellent core hardenability while maintaining high fixing accuracy.

In the optical pickup device, a photocurable adhesive is used to fix the photodetector to the housing (Patent Documents 1 and 2). This adhesive is required to have high fixing accuracy and high core hardenability.

Fixed accuracy is the precision which shows that when a photodetector is fixed to a housing, it does not move from a predetermined position. If the fixing accuracy is low, the photodetector moves from the predetermined position during the manufacture of the optical pickup device or after the endurance test, and the photodetection cannot be performed. Therefore, high fixing precision is required.

The core hardenability is an index indicating how deep to harden when irradiated with light from the top, and the higher the core hardenability, the better.

Considering the fixed accuracy, the photocurable adhesive is superior to the photocurable acrylic resin adhesive than the photocurable acrylic resin adhesive. Moreover, a cation curable epoxy resin adhesive does not have hardening inhibition by oxygen like an acrylic resin adhesive, and is excellent also in thin film curability (nonpatent literature 1). However, the cationically curable epoxy resin had a problem that the core part curability was bad.

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-251776 Patent Document 2: Japanese Patent Application Laid-Open No. 2007-35238

"Epoxy resin handbook", 236 pages, digestion 62 years (1987) December 25, first edition first publication issuance

This invention makes it a subject to solve the problem that core part sclerosis | hardenability is bad in the energy ray hardening type epoxy resin composition with high fixed precision, maintaining high fixed precision.

The present invention is an energy ray-curable epoxy resin composition comprising an epoxy resin, a filler and a photoacid generator, wherein a difference between the refractive index of the filler and the refractive index of the energy ray-curable epoxy resin composition not containing the filler is within ± 0.02. Epoxy resin composition.

Regarding the fixing accuracy, low curing shrinkage is important to prevent the position-adjusted photodetector from moving due to curing shrinkage during curing of the photocurable adhesive, and high elastic modulus when hot is the weight of the photodetector when hot It is important to prevent movement by the tension of the FPC (polyimide wiring) attached to the photodetector, and it indicates that the photocurable adhesive does not soften and is hard even when hot. As a result of various studies, the present inventors have found that, in order to obtain high fixing accuracy, the curing shrinkage ratio of the epoxy resin composition needs to be 3% or less and that the elasticity modulus when hot (temperature of 100 ° C in the endurance test) is 50 MPa or more.

Regarding depth curability, the present inventors have found that it is preferable to measure by a predetermined method (10 seconds of UV irradiation time) as a result of various examinations, and to have a depth curability of 2 mm or more if possible.

According to this invention, the core part curability of a resin composition can be improved significantly, maintaining high fixed precision.

The energy-beam curable epoxy resin composition of this invention contains an epoxy resin, a filler, and a photoacid generator.

Although it does not specifically limit as an epoxy resin, For example, a bisphenol-A epoxy resin, a bisphenol F-type epoxy resin, a biphenyl type epoxy resin, a naphthalene type epoxy resin, a phenol novolak-type epoxy resin, a cresol novolak-type epoxy resin, hydrogen Addition bisphenol-A epoxy resin, hydrogenated bisphenol F-type epoxy resin, polybutadiene type epoxy resin, polyisoprene-type epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, etc. can be illustrated. These resins may be used alone, or may be used in combination of two or more thereof.

As the alicyclic epoxy resin, for example, vinylcyclohexene monooxide 1,2-epoxy-4-vinylcyclohexane (CEL2000), 1,2: 8,9 diepoxylimonene (CEL3000), 3,4-epoxycyclohex Cenylmethyl-3 ', 4'-epoxycyclohexenecarboxylate (CEL2021P), 1,2-epoxy-4- (2-oxyranyl) cyclohexane of 2,2-bis (hydroxymethyl) -1-butanol Addition product (EHPE3150), 3, 4- epoxycyclohexenylmethyl-3 ', 4'- epoxycyclohexene carboxylate, hydrogenated biphenyl type alicyclic epoxy resin, etc. are mentioned. You may use individually, respectively or you may use in combination of 2 or more type.

As the aliphatic epoxy resin, for example, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, trimethylolpropane diglycidyl ether, polyethylene glycol diglycidyl ether, and the like. Can be mentioned. You may use individually, respectively or you may use in combination of 2 or more type.

Preferred epoxy resins include bisphenol A type epoxy resins (e.g., epiclon 850 or Epiclone 860 manufactured by DIC Corporation), hydrogenated bisphenol A type epoxy resins (e.g., YX8034 manufactured by jER Corporation), Especially preferable is Epiclone 860 by DIC Corporation.

In this invention, the refined thing can also be used as phenol type epoxy resins, such as a bisphenol-A epoxy resin. In the phenol type epoxy resin, epichlorohydrin used for synthesis | combination and the halogen containing intermediate which are not ring-closed by an epoxy group exist as an impurity. Such impurities are not cured in the presence of a cation curing catalyst even when irradiated with energy rays. Therefore, by using the phenol type epoxy resin which removed these impurities, the uncured component in the hardened | cured material after hardening with an energy beam can be reduced, and the low-halogen-containing energy-beam curable epoxy resin composition can be obtained.

As the purification of a phenol type epoxy resin, for example, purification by distillation, purification by chromatography using silica gel, alumina, or the like, purification by hydrolysis of halogen bound by covalent bonds with an aqueous alkaline solution such as aqueous sodium hydroxide solution, and the like. Can be mentioned. As a regular product of the bisphenol A type epoxy resin, EXA-8067 can be obtained from DIC.

In the energy ray-curable epoxy resin composition of the present invention, the amount of halogen is preferably 500 ppm or less from the viewpoint of electrocorrosion (corrosion) and global environmental problems. By using EXA-8067 as the epoxy resin, in addition to the effects of the present invention described above, low halogenation can be achieved.

Examples of the fillers include acrylic fillers, styrene fillers, acrylic / styrene copolymer fillers, fluorine resin fillers, polyethylene fillers, polypropylene fillers, silicone fillers, silica fillers, mica and talc. You may use individually, respectively or you may use in combination of 2 or more type. Preferred fillers are acrylic / styrene copolymer fillers, polyethylene fillers, polypropylene fillers and glass fillers, and more preferred fillers are acrylic / styrene copolymer fillers. The addition amount of a filler becomes like this. Preferably it is 5-100 weight part with respect to 45 weight part epoxy resin, More preferably, it is 15-60 weight part.

In the energy ray-curable epoxy resin composition of the present invention, the difference between the refractive index of the filler and the refractive index of the energy ray-curable epoxy resin composition containing no filler is within ± 0.02, and preferably within ± 0.01. Here, the energy-beam curable epoxy resin composition which does not contain a filler means the epoxy resin composition remove | excluding the filler from the energy-beam curable epoxy resin composition of this invention containing an epoxy resin, a filler, a photo-acid generator, and arbitrary components. By selecting the filler or selecting the epoxy resin or other additives which may be optionally included later, the difference between the refractive index of the filler and the refractive index of the energy ray-curable epoxy resin composition containing no filler can be within a predetermined range. Can be.

The photoacid generator is not limited as long as it is a compound that generates Lewis acid or Bronsted acid by irradiation with energy rays, and sulfonium salts and iodonium salts may be mentioned. The amount of the photoacid generator used is preferably 0.5 to 10 parts by weight, and more preferably 1 to 4 parts by weight with respect to 45 parts by weight of the epoxy resin. The photoacid generator can also be dissolved or dispersed in a solvent such as 4-butyrolactone and added.

As the sulfonium salt, for example, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, 4,4'-bis [diphenyl Sulfonio] diphenylsulfide bishexafluorophosphate, 4,4'-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenylsulfide bishexafluoroantimonate, 4,4 '-Bis [di (β-hydroxyethoxy) phenylsulfonio] diphenylsulphide bishexafluorophosphate, 7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone Hexafluoroantimonate, 7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone tetrakis (pentafluorophenyl) borate, 4-phenyl carbonyl-4'-diphenyl Sulfonio-diphenylsulphide hexafluorophosphate, 4- (p-tert-butylphenyl carbonyl) -4'-diphenylsulfonio-diphenylsulphide hexafluoroanti Nate, 4- (p-tert-butylphenyl carbonyl) -4'-di (p-toluyl) sulfonio-diphenylsulfide tetrakis (pentafluorophenyl) borate, manufactured by Asahi Denkasa SP-170 , SP-172, SP-150, SP-152, CPI-210S manufactured by San Apro Co., etc. may be mentioned. As a sulfonium salt, SP-170, SP-172, or San Apro Co., Ltd. CPI-210S by Asahi Denka Co., Ltd. is preferable. These salts may be used alone, or may be used in combination of two or more thereof.

As the iodonium salt, for example, diphenyliodonium tetrakis (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, di (4-nonylphenyl) iodonium Hexafluoro phosphate, the Rhodia company PI2074, etc. are mentioned. Rhodia's PI2074 is preferable as an iodonium salt. These salts may be used alone, or may be used in combination of two or more thereof.

The energy ray-curable epoxy resin composition of the present invention may contain other additives such as an oxetane compound, a photosensitizer, and a silane coupling agent.

An oxetane compound is added for the purpose of low viscosity and low shrinkage rate in order to improve coating workability. As the oxetane compound, 3-ethyl-3-hydroxymethyloxetane (OXA), 1,4-bis [{(3-ethyl-3-oxetanyl) methoxy} methyl] benzene (XDO), 3- Ethyl-3- (phenoxymethyl) oxetane (OXT-211 (POX)), 2-ethylhexyl oxetane (OXT-212 (EHOX)), xylylenebisoxetane (OXT-121 (XDO)), Bis (3-ethyl-3-oxetanylmethyl) ether (OXT-221 (DOX)), oxetanylsilicate OXT-191, 3-ethyl-[{(3-triethoxysilylpropoxy) methyl) jade Cetane, oxetanyl silsesquioxane, a phenol novolak oxetane, etc. are mentioned. The parenthesis shows the product number of Toago Kosa. The amount of the oxetane compound added is preferably 5 to 100 parts by weight, and more preferably 10 to 50 parts by weight with respect to 45 parts by weight of the epoxy resin. Each oxetane compound may be used individually, or may be used in combination of 2 or more type.

Although it does not specifically limit as a photosensitizer, For example, a carbonyl compound, an organic sulfur compound, a persulfide, a redox type compound, an azo and a diazo compound, a halogen compound, a photoreducible dye etc. are mentioned. Specific examples of the photosensitizer include benzoin derivatives such as benzoin methyl ether, benzoin isopropyl ether, and α, α-dimethoxy-α-phenylacetophenone; Benzophenone derivatives such as benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, and 4,4'-bis (diethylamino) benzophenone; Thioxanthone derivatives such as 2,4-diethyl thioxanthone, 2-chloro thioxanthone and 2-isopropyl thioxanthone; Anthraquinone derivatives such as 2-chloroanthraquinone and 2-methyl anthraquinone; Acridone derivatives such as N-methylacridone and N-butylacridone; In addition, the (alpha), (alpha)-diethoxy acetophenone, benzyl, a fluorenone, a xanthone, a uranyl compound, etc. are mentioned. These photosensitizers may be used alone or in combination of two or more thereof. Preferable photosensitizer is 2, 4- diethyl thioxanthone (DETX-S by Nippon Kayaku Co., Ltd.). The addition amount of a photosensitizer is 0.001-1 weight part with respect to 45 weight part epoxy resin, Preferably it is 0.005-0.1 weight part. When the iodonium salt-based PI2074 is used as the photoacid generator, the use of the photosensitizer DETX-S is suitable, and the amount thereof is preferably 0.001 to 0.1 parts by weight, particularly preferably 0.01 to 45 parts by weight of the epoxy resin. Parts by weight. When CPI-210S of sulfonium salt type | system | group is used as a photo-acid generator, a photosensitizer is not necessarily required and it is excellent in sclerosis | hardenability without adding this.

The silane coupling agent is added for the purpose of providing adhesion. As the silane coupling agent, for example, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, dimethoxydiethoxysilane, dimethoxydiisopropoxysilane, die Tetra alkoxysilanes such as methoxydiisopropoxysilane and diethoxydibutoxysilane; Trialkoxysilanes, such as methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, ethyltriethoxysilane, ethyltributoxysilane, cyclohexyl triethoxysilane, and phenyl triisopropoxysilane ; Examples of dialkoxysilanes such as dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, diethyldibutoxysilane, and phenylethyldiethoxysilane can be exemplified. You may use these silane coupling agents individually or in combination of 2 or more types. The amount of the silane coupling agent added is preferably 0.1 to 10 parts by weight, and more preferably 0.5 to 5 parts by weight with respect to 45 parts by weight of the epoxy resin.

The energy ray-curable epoxy resin composition of the present invention has a high optical component such as an optical component such as an LD (laser diode), a photodetector (PD: photodetector), a lens, a prism, or an optical component such as a lens. Since it can fix quickly with a fixed precision, it is useful as an adhesive agent for optical device assembly. As the optical device, for example, in the optical pickup device described in Patent Documents 1 and 2 and paragraph 0023 of Japanese Patent Application Laid-Open No. 2007-311006, it can be used for fixing after adjusting the inclination of the actuator with a skew screw. Moreover, it can also be used for fixing optical components, such as a mirror, and fixing a suspension wire.

Example

Below, an Example demonstrates this invention. In addition, a compounding quantity is shown by weight part.

Example 1 and Comparative Examples 1 and 2

Based on the formulations described in Table 1, the photoacid generator PI2074 was dissolved in 4-butyrolactone, added to Epiclone 850 and CEL3000, stirred until clear, and the energy ray curable epoxy resin composition of Comparative Example 1 was prepared. .

Based on the mixing | blending shown in Table 1, GS350T or GS310T was added to the epoxy resin composition of the comparative example 1, and it stirred until it became uniform, and manufactured the energy-beam curable epoxy resin composition of Example 1 or the comparative example 2.

Deep part curability of the epoxy resin compositions of Example 1 and Comparative Examples 1 and 2 was measured. Core hardening property is filled into the black tube which the hole of 5 mm (phi) opened, each Example 1 and Comparative Examples 1 and 2 so that the energy-beam curable epoxy resin composition may be 5 mm in height, and 500mW / after 10 seconds irradiation of cm ² (365nm), take out the cured product from the black tube, followed by measuring the thickness of a portion that is cured by removing the uncured parts with a micrometer. The results are shown in Table 1.

Example 2 and Comparative Examples 3 and 4

Based on the blending described in Table 2, the epoxy resin compositions of Example 2 and Comparative Examples 3 and 4 were prepared. Deep curing property of each epoxy resin composition was measured. The results are shown in Table 2.

Example 3 and Comparative Example 5

Based on the mixing | blending of Table 3, the epoxy resin composition of Example 3 and the comparative example 5 was manufactured. Deep curing property of each epoxy resin composition was measured. The results are shown in Table 3.

[Test Example 1]

About each of the epoxy resin compositions of Examples 2 and 3 and Comparative Example 3, the cure shrinkage rate and the elasticity rate were measured. Hardening shrinkage was measured according to the cup method described in JIS K6833. The elastic modulus was measured by the plate tensioning method using EXSTAR6000 made from SII. Suitable results are shown in Table 4.

[Examples 4 and 5]

Based on the mixing | blending shown in Table 5, the base (epoxy resin composition which does not contain a filler) of the energy-beam curable epoxy resin compositions of Examples 4 and 5 was produced.

On each of the bases of Examples 4 and 5, Art Pearl GS-310T (refractive index 1.51), Art Pearl GS-320T (refractive index 1.52), Art Pearl GS-330T (refractive index 1.53) and Art Pearl GS-350T (refractive index 1.55), respectively. 45 parts by weight of was added to prepare eight types of energy ray-curable epoxy resin compositions.

[Test Example 2]

About eight types of energy-beam curable epoxy resin compositions manufactured in Examples 4 and 5, the core-hardness was measured in the same manner as in Example 1 except that the UV irradiation time was changed from 10 seconds to 20 seconds. The results are shown in Table 6.

[Examples 6 to 8]

Based on the compounding shown in Table 7, the energy-beam curable epoxy resin compositions of Examples 6-8 were manufactured.

EXA-8067: bisphenol A epoxy resin (DIC company make: distillation product)

I-651: 2,2-dimethoxy-1,2-diphenylethane (Siba Corporation sensitizer)

[Test Example 3]

LED curability of each of the energy-beam curable epoxy resin compositions of Examples 6 and 7 was tested. LED curability drops 1 drop of an energy ray-curable epoxy resin composition onto an aluminum plate, irradiates it for 10 seconds with an illuminance of 500 mW / cm ² (illuminometer Hamamatsu Photonics C6080-13) with an LED illuminator having a wavelength of 365 nm, and cures it. , The curing state was confirmed by finger touch. The criteria of LED curability were (circle): hardening (solid) and x table | surface: uncured (liquid phase). The test results are shown in Table 8.

[Test Example 4]

The halogen amount of each of the energy-beam curable epoxy resin compositions of Examples 6 and 8 was measured by EN14582 combustion ion chromatography method. Table 9 shows the measurement results.

[Test Example 5]

The core part curability of each of the energy-beam curable epoxy resin compositions of Examples 6 and 8 was measured. Deep curing property by an ultraviolet lamp is filled with an energy-beam hardening type epoxy resin composition in the black tube of length 5mm of inner diameter 5mmφ, and illuminates ultraviolet-ray from the top with an ultraviolet irradiator (LC5 by Hamamatsu Photonics) 500mW / cm <^2> (365nm) It was irradiated for 10 seconds with a (light meter: C6080-13 manufactured by Hamamatsu Photonics), and the length of the cured energy ray curable epoxy resin composition was measured. Core hardening property by LED fills an energy-beam hardening type epoxy resin composition into the black tube of length 5mm of inner diameter 5mmφ, and illuminance 500mW / cm <^2> from a top with an LED irradiator of wavelength 365nm (Rimometer: Hamamatsu Photonics C6080-13) ) For 10 seconds to measure the length of the cured energy ray curable epoxy resin composition. Table 10 shows the measurement results.

[Test Example 6]

The hardness, cure shrinkage rate, and elastic modulus of each of the energy ray-curable epoxy resin compositions of Examples 6 and 8 were measured. The hardness (D) was measured by the durometer described in JIS K 7215. Hardening shrinkage was measured according to the cup method described in JIS K6833. Tanδ and storage modulus were measured by the plate tensioning method using EXSTAR6000 manufactured by SII.

Industrial Applicability

According to the energy ray-curable epoxy resin composition of this invention, optical components, such as LD, a photodetector, a lens, and a prism, optical modules, etc. in which optical components, such as a lens, can be fixed with a high fixed precision with deep-hardenability. Therefore, it is useful as an adhesive agent for optical device assembly.

Claims (8)

An energy ray-curable epoxy resin composition comprising an epoxy resin, a filler, and a photoacid generator, wherein the difference between the refractive index of the filler and the refractive index of the energy ray-curable epoxy resin composition not containing the filler is within ± 0.02. The epoxy resin composition according to claim 1, wherein a difference between the refractive index of the filler and the refractive index of the energy ray-curable epoxy resin composition not containing the filler is within ± 0.01. The epoxy resin composition according to claim 1 or 2, wherein the filler is a copolymer of an acrylic resin and a styrene resin. The epoxy resin composition according to any one of claims 1 to 3, further comprising an oxetane compound. The epoxy resin composition according to any one of claims 1 to 4, which is an adhesive for assembling an optical device. The epoxy resin composition according to any one of claims 1 to 4, which is an adhesive for assembling an optical pickup device. The optical device assembled using the epoxy resin composition of Claim 5. An optical pickup device assembled using the epoxy resin composition according to claim 6.