JP2013213220A - Epoxy resin composition, cured product thereof, resin composition for sealing photosemiconductor, and photosemiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin composition significantly excellent in transparency, heat resistance and strength of a cured product thereof.SOLUTION: An epoxy resin composition comprises essentially a bisphenol type epoxy resin (A) having an epoxy equivalent of 150-1,000 g/eq; an epoxy group-containing olefin polymer (B); and an acid anhydride curing agent (C) for the epoxy resin.

Description

  The present invention relates to an epoxy resin composition suitable for an optical semiconductor sealing resin composition, a cured product thereof, an optical semiconductor sealing resin composition, and an optical semiconductor device.

  Optical semiconductor devices such as LEDs, photocouplers, optical sensors, semiconductor lasers, and image sensors have been widely used in recent years as light-emitting elements or optical transmission devices. As resin materials for sealing optical semiconductor elements, aromatic epoxy resins and A two-component curing agent in combination with an acid anhydride curing agent is used because of its excellent molding processability and transparency.

  However, the sealing material using the above-described aromatic epoxy resin as a main agent tends to cause yellowing of a cured product due to absorption of an aromatic ring in the resin, and particularly in the LED field, the output of the LED element is increased and shortened. As the wavelength has progressed, the aromatic epoxy resin easily absorbs light of this short wavelength, causing yellowing of the optical semiconductor element and a decrease in light extraction efficiency.

  Therefore, aliphatic cyclic epoxy compounds such as 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate as an optical semiconductor encapsulating material with little yellowing of the cured product and excellent strength and heat resistance As a main agent, a technique using acid anhydride as a main curing agent is known (see Patent Document 1).

  However, a sealing material containing the aliphatic cyclic epoxy compound as a main component and an acid anhydride as a curing agent has a drawback that a suitable strength cannot be obtained because the cured product is hard and brittle. In addition, as a means of improving this solid and brittle property, there is a method of blending a flexible resin component, but in this case, the heat resistance of the cured product is inevitably lowered and usually has both heat resistance and strength. It was difficult to do.

JP 2009-114390 A

  Therefore, the problem to be solved by the present invention is to provide an epoxy resin composition that is remarkably excellent in transparency, heat resistance and strength of a cured product.

The present inventors have made intensive studies to solve the above problems, the epoxy resin composition a low molecular weight bisphenol type epoxy resin and an acid anhydride hardening agent as essential components, formulating an epoxy group-containing olefin polymer As a result, it was found that the strength was drastically improved while maintaining excellent transparency and heat resistance in the cured product, and the present invention was completed.

That is, the present invention has an epoxy equivalent of 150 to 1000 g / eq. Bisphenol type epoxy resin (A), the relates to an epoxy resin composition, characterized in that the epoxy group-containing olefin polymer (B), and an acid anhydride Monoe epoxy resin curing agent (C) as essential components.

  The present invention further relates to an optical semiconductor sealing resin composition comprising the above epoxy resin composition.

  The present invention further relates to a cured product obtained by shaping the epoxy resin composition and then curing it by heating or irradiation with active energy rays.

  ADVANTAGE OF THE INVENTION According to this invention, the epoxy resin composition which is remarkably excellent in transparency, heat resistance, and intensity | strength of hardened | cured material can be provided.

  Hereinafter, the present invention will be described in detail.

Epoxy resin (A) used in the present invention, e epoxy equivalent 150~1000g / eq. It is a bisphenol type epoxy resin.

The epoxy equivalent used in the present invention is 150 to 1000 g / eq. Bisphenol type epoxy resin (A), bisphenol A type epoxy resin, bisphenol F type epoxy resins, and bisphenol S type epoxy resins. Among these, a bisphenol A type epoxy resin is particularly preferable from the viewpoint of excellent balance between rigidity of the cured product and heat and humidity resistance. The epoxy equivalent of the bisphenol-type epoxy resin (A) is 150 to 500 g / eq. It is preferable that it is the range of these.

  Next, the epoxy group-containing olefin polymer (B) used in the present invention includes, for example, a copolymer of an epoxy group-containing vinyl monomer and other polymerizable vinyl monomers. In this invention, intensity | strength can be improved without reducing the heat resistance of hardened | cured material by using this epoxy group containing olefin polymer (B). Examples of the epoxy group-containing vinyl monomer used here include various glycidyl esters of (meth) acrylic acid such as glycidyl (meth) acrylate or β-methylglycidyl (meth) acrylate, and (meth) allyl. Examples include allyl glycidyl ethers such as glycidyl ether and (meth) allylmethyl glycidyl ether, and various alicyclic epoxy group-containing vinyl monomers such as 3,4-cyclohexyl acrylate and 3,4-cyclohexyl methacrylate. It is done.

  Examples of other vinyl monomers copolymerizable with these epoxy group-containing monomers include, for example, various acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, and cyclohexyl acrylate; methyl methacrylate, ethyl Various methacrylates such as methacrylate, butyl methacrylate, cyclohexyl methacrylate, benzyl acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl ( Various waters such as meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate Group-containing (meth) acrylates; or the main component of addition reaction of these (meth) acrylates and ε-caprolactone; various carboxyl groups such as (meth) acrylic acid, crotonic acid, itaconic acid, maleic acid or fumaric acid Mono- or diesters of various monomers containing polyvalent carboxyl groups such as itaconic acid, maleic acid, fumaric acid and the like, and monoalkyl alcohols having 1 to 18 carbon atoms; or N-dimethyl Various amino group-containing amide unsaturated monomers such as aminoethyl (meth) acrylamide, N-diethylaminoethyl (meth) acrylamide, N-dimethylaminopropyl (meth) acrylamide, N-diethylaminopropyl (meth) acrylamide; Dimethylaminoethyl (meth) acrylate, diethylamino Various dialkylaminoalkyl (meth) acrylates such as noethyl (meth) acrylate; tertiary (tert-) butylaminoethyl (meth) acrylate, tert-butylaminopropyl (meth) acrylate, aziridinylethyl (meth) ) Various amino group-containing monomers such as acrylates, pyrrolidinylethyl (meth) acrylates, piperidinylethyl (meth) acrylates, various α-olefins such as ethylene, propylene, butene 1; fluoroolefins such as vinyl chloride and vinylidene chloride Various halogenated olefins except styrene; various aromatic vinyl compounds such as styrene, α-methylstyrene and vinyltoluene; γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxy Various hydrolyzable silyl group-containing monomers such as silane and γ- (meth) acryloyloxypropylmethyldimethoxysilane; vinyl fluoride, vinylidene fluoride, trifluoroethylene, tetrafluoroethylene, chlorotrifluoroethylene, bromotrifluoro Various fluorine-containing α-olefins such as ethylene, pentafluoropropylene and hexafluoropropylene; various perfluorovinyl ethers such as trifluoromethyl trifluorovinyl ether, pentafluoroethyl trifluorovinyl ether and heptafluoroethyl trifluorovinyl ether , Fluorine-containing vinyl monomers such as (per) fluoroalkyl vinyl ether (alkyl group having 1 to 18 carbon atoms); vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, cap Various aliphatic carboxylates such as vinyl acetate, vinyl caprate, vinyl caprate, vinyl laurate, branched aliphatic carboxylate having 9 to 11 carbon atoms, vinyl stearate; vinyl cyclohexanecarboxylate, methylcyclohexane Various vinyl esters of carboxylic acid having a cyclic structure such as vinyl carboxylate, vinyl benzoate, vinyl p-tert-butylbenzoate, and the like can be mentioned, and these can be used alone or as a mixture of two or more.

  The polymerization ratio of the epoxy group-containing vinyl monomer and the other vinyl monomers described above is the mass ratio of the monomer at the time of production [epoxy group-containing vinyl monomer / other vinyl monomers. The body] is preferably in a ratio of 20/80 to 60/40 from the viewpoint of excellent effect of improving the strength of the cured product.

  Further, the epoxy group-containing olefin polymer (B) has a softening point of 80 by the ring-and-ball method (5 ° C./min temperature raising method) from the viewpoint of excellent balance between the fluidity at the time of melting the composition and the strength of the cured product. What is in the range of -120 degreeC is preferable. Furthermore, the epoxy equivalent of the epoxy group-containing olefin polymer (C) is 300 to 600 g / eq. It is preferable that it exists in the range.

Anhydride Monoe epoxy resin curing agent (C) used in the present invention is, for example, tetrahydrophthalic anhydride, methyl tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyl hexahydrophthalic anhydride, methyl-end ethylene-tetrahydrophthalic anhydride Cyclic aliphatic acid anhydrides such as acid, trialkyltetrahydrophthalic anhydride and methylnadic anhydride; aromatic acid anhydrides such as phthalic anhydride, trimellitic anhydride and pyromellitic anhydride; unsaturated such as maleic anhydride Examples thereof include carboxylic acid anhydrides. Among these, cycloaliphatic acid anhydrides are preferable from the viewpoint of excellent transparency of the cured product, and acid anhydrides having a viscosity at 25 ° C. of 500 mPa · s or less from the viewpoint of excellent fluidity when the composition is melted. It is preferable that

Above in detail epoxy resin (A), the mixing ratio of the components of the epoxy group-containing olefin polymer (B), and an acid anhydride Monoe epoxy resin curing agent (C) is an epoxy group-containing epoxy resin (A) The mass ratio [(A) / (B)] to the olefin polymer (B) is a ratio of 55/45 to 95/5, and the epoxy resin (A) and the epoxy group-containing olefin polymer ( to the epoxy groups of B), the equivalent ratio of anhydride groups in the anhydride Monoe epoxy resin curing agent (C) [acid anhydride groups / epoxy group] 0.7 / 1.0 to 1.1 /1.0 is preferable from the viewpoint of excellent curability and strength of the cured product.

  The epoxy resin composition of the present invention can be used in combination with other curing agents and curing accelerators as appropriate.

  Other curing agents include, for example, amine BF3 complex compounds; Bronsted acid salts such as aliphatic sulfonium salts, aromatic sulfonium salts, iodonium salts, and phosphonium salts; adipic acid; sebacic acid; terephthalic acid; trimellitic acid And polycarboxylic acids such as carboxyl group-containing polyesters. The amount of the other curing agent used is preferably in the range of 1 to 10 parts by weight with respect to 100 parts by weight of the acid anhydride epoxy resin curing agent (C).

  Various curing accelerators can be used, and examples thereof include phosphorus compounds, tertiary amines, imidazoles, organic acid metal salts, Lewis acids, and amine complex salts. In particular, when used as an optical semiconductor sealing material application, from the viewpoint of excellent curability, heat resistance, electrical properties, moisture resistance reliability, etc., phosphorous compounds are triphenylphosphine, and tertiary amines are 1,8- Diazabicyclo- [5.4.0] -undecene (DBU) is preferred.

  As the usage-amount of the said hardening accelerator, 0.1-0.1 with respect to 100 weight part of total mass of the said epoxy resin (A) and the epoxy-group containing olefin polymer (B) in the epoxy resin composition which concerns on this invention. It is preferable from the viewpoint of curability that the ratio is in the range of 5 parts by weight, especially in the range of 0.2 to 2 parts by weight.

  In addition to the above components, a colorant, a coupling agent, a leveling agent, a release agent, a lubricant, and the like can be appropriately added to the epoxy resin composition of the present invention depending on the purpose.

  The colorant is not particularly limited. Inorganic pigments such as chrome vermilion, valve shell, cobalt violet, bitumen, ultramarine, carbon black, chrome green, chromium oxide, cobalt green and the like can be mentioned.

  Examples of the leveling agent include oligomers having a molecular weight of 4000 to 12000 made of acrylates such as ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate, epoxidized soybean fatty acid, epoxidized abiethyl alcohol, hydrogenated castor oil, and titanium coupling agent. Etc. Examples of the lubricant include hydrocarbon lubricants such as paraffin wax, microwax and polyethylene wax, higher fatty acid lubricants such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid and behenic acid, stearylamide, palmitylamide Higher fatty acid amide lubricants such as oleylamide, methylenebisstearamide, ethylenebisstearamide, hydrogenated castor oil, butyl stearate, ethylene glycol monostearate, pentaerythritol (mono-, di-, tri-, or tetra -) Higher fatty acid ester lubricants such as stearate, alcohol lubricants such as cetyl alcohol, stearyl alcohol, polyethylene glycol, polyglycerol, lauric acid, myristic acid, palmitic acid, stearic acid, arachidin , Behenic acid, ricinoleic acid, such as magnesium naphthenate, calcium, metal soaps is cadmium, barium, zinc, metal salts such as lead, carnauba wax, candelilla wax, beeswax, and natural waxes such as montan wax.

  As the coupling agent, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxy Silane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane , Vinyltrimethoxysilane, N- (2- (vinylbenzylamino) ethyl) 3-aminopropyltrimethoxysilane hydrochloride, 3-methacryloxypropyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropylto Silane coupling agents such as limethoxysilane, isopropyl (N-ethylaminoethylamino) titanate, isopropyl triisostearoyl titanate, titanium di (dioctyl pyrophosphate) oxyacetate, tetraisopropyl di (dioctyl phosphite) titanate, neo Titanium coupling agents such as alkoxytri (p-N- (β-aminoethyl) aminophenyl) titanate, Zr-acetylacetonate, Zr-methacrylate, Zr-propionate, neoalkoxyzirconate, neoalkoxytrisneodecanoyl Zirconate, Neoalkoxytris (dodecanoyl) benzenesulfonyl zirconate, Neoalkoxytris (ethylenediaminoethyl) zirconate, Neoalkoxytris (m-aminophenyl) Rukoneto, ammonium zirconyl Niu arm carbonate, Al- acetylacetonate, Al- methacrylate, zirconium or the like Al- propionate, or Aluminum-based coupling agents is preferably silicon-based coupling agent. By using a coupling agent, moisture-reliability is excellent, and a cured product with little decrease in adhesive strength after moisture absorption can be obtained.

  Release agents include hydrocarbon lubricants such as paraffin wax, microwax, polyethylene wax, higher fatty acid lubricants such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and behenic acid, stearylamide, palmityl. Higher fatty acid amide type lubricants such as amide, oleylamide, methylene bisstearamide, ethylene bisstearamide, hydrogenated castor oil, butyl stearate, ethylene glycol monostearate, pentaerythritol (mono-, di-, tri-, or Higher fatty acid ester lubricants such as tetra-) stearate, alcohol lubricants such as cetyl alcohol, stearyl alcohol, polyethylene glycol, polyglycerol, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, Metallic soaps such as magnesium, calcium, cadmium, barium, zinc, lead, etc., such as hemonic acid, ricinoleic acid, naphthenic acid, etc., and natural waxes such as carnauba wax, candelilla wax, beeswax, montan wax, etc. Higher fatty acid esters, higher fatty acid amides, higher fatty acids, metal soaps, hydrocarbon lubricants, more preferably zinc stearate, magnesium stearate, stearic acid, pentaerythritol (mono-, di-, tri-, Or tetra-) stearate.

  The epoxy resin composition of the present invention can be easily obtained as a liquid composition by uniformly stirring the above-described components.

  The curing reaction of the epoxy resin composition of the present invention is preferably in the temperature range of 100 to 170 ° C, for example.

  As described above, the composition of the present invention described above is excellent in fluidity and excellent in transparency and strength of the cured product. Therefore, various compositions such as LED, phototransistor, photodiode, photocoupler, CCD, EPROM, and photosensor are available. It is useful as a sealing material for an optical semiconductor device, and particularly useful as a sealing material for a high-brightness LED element that generates significant heat during light emission. Here, the high-brightness LED element means an element having a luminous flux of 100 lumens (1 m) or more.

  As the high-brightness LED, a blue to white LED having a main light emission peak at a wavelength of 350 to 550 nm and a compound semiconductor composed of four elements of aluminum, gallium, indium, and phosphorus are used, and the element composition is adjusted. And quaternary LEDs that enable red, orange, yellow, and yellow-green color development.

As the application of the former blue to white LED having a main emission peak at a wavelength of 350 to 550 nm, it is used for a backlight source for liquid crystal panels used in portable DVD players, car navigation systems, laptop computers, etc. 10 -17 type liquid crystal panel backlight light source, automobile headlamp light source, and the like.
On the other hand, the use of quaternary LEDs includes outdoor displays, rear lamps and interior lighting of automobiles, backlights of liquid crystal displays of thin televisions and personal computers.

  The optical semiconductor device of the present invention is, for example, transfer molded or casted with the epoxy resin composition of the present invention to the above-mentioned epoxy resin composition that has been sufficiently degassed, for example, an optical semiconductor to which an electrode such as a lead wire is attached. Examples thereof include a method of sealing and curing by a molding method, a method of previously mounting an optical semiconductor on a circuit board, sealing it with the epoxy resin composition of the present invention, and curing. Specifically, it can be obtained by pouring into a mold set with an optical semiconductor element, followed by heat curing under the above temperature conditions.

  The optical semiconductor device of the present invention includes various optical semiconductor devices enumerated as applications of the above-described epoxy resin composition, specifically, light receiving elements such as LEDs, phototransistors, photodiodes, photocouplers, CCDs, EPROMs, and photosensors. And an optical semiconductor device in which a light emitting element or the like is sealed. Among these, LED devices, particularly high-intensity LED devices are particularly preferable, and blue to white LED devices having a main emission peak at a wavelength of 350 to 550 nm and quaternary LED devices are particularly preferable.

Next, the present invention will be specifically described with reference to Examples and Comparative Examples. In the following, “parts” and “%” are based on weight unless otherwise specified. In addition, each physical property evaluation was measured on condition of the following.
1) Varnish viscosity: Measured at 25 ° C. using an E-type viscometer (“TV-20 type” cone plate type manufactured by Toki Sangyo Co., Ltd.).
2) Glass transition temperature: Measured by using a viscoelasticity measuring apparatus (solid rheometric measuring apparatus “RSAII” manufactured by Rheometric Co., Ltd., double currant lever method; frequency 1 Hz, temperature rising rate 3 ° C./min).
3) Initial transmittance: Measured using a spectrophotometer “UV-3150” (manufactured by Shimadzu Corporation).
4) Transmittance after heat resistance test: The light transmittance at a wavelength of 400 nm of the cured epoxy resin after heating at 150 ° C. for 72 hours was measured.
5) Flexural strength, flexural modulus, strain: compliant with JIS6911.

Examples 1 and 2 and Comparative Example 1
According to the formulation shown in Table 1 below, each component was blended to obtain an epoxy resin composition. Varnish viscosity and storage stability were evaluated using this epoxy resin composition.
Also, this epoxy resin composition was poured into a mold gap in which a spacer (silicone tube) having a thickness of 3 mm was sandwiched between glass plates, cured at 120 ° C. for 1 hour, further heated to 160 ° C. and heated to 160 ° C. After reaching, the cured product was obtained by holding at that temperature for 2 hours, and various evaluation tests were performed using this as a test piece. The results are shown in Table 1.

In addition, each component shown in the said Table 1 is as follows.
BPA type epoxy resin: Bisphenol A type epoxy resin (“Epiclon 850S” epoxy equivalent 188 g / eq. Manufactured by DIC Corporation)
Epoxy group-containing olefin polymer (A): copolymer of glycidyl methacrylate and methyl methacrylate (epoxy equivalent: 430 g / eq.)
Epoxy group-containing olefin polymer (B): copolymer of glycidyl methacrylate and methyl methacrylate (epoxy equivalent 500 g / eq.)
Acid anhydride: Methylhexahydrophthalic anhydride (HN-5500E manufactured by Hitachi Chemical Co., Ltd.)
BHT: Dibutylhydroxytoluene HCA: 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide JP-202: Diethyl phosphite Curing accelerator manufactured by Johoku Chemical Industry Co., Ltd .: Methyltributylphosphonium dimethyl phosphate Name "Hishicolin PX-4MP" manufactured by Nippon Chemical Industry Co., Ltd.)

Claims (5)

Epoxy equivalent 150-1000 g / eq. Bisphenol type epoxy resin (A), the epoxy group-containing olefin polymer (B), and an acid anhydride Monoe epoxy resin curing agent (C) an epoxy resin composition characterized by containing, as essential components. The blending ratio of the components (A) to (C) is such that the mass ratio [(A) / (B)] of the epoxy resin (A) and the epoxy group-containing olefin polymer (B) is 55/45 to 95. a ratio becomes / 5, and the epoxy resin (a) and an epoxy group-containing olefin polymer to epoxy groups (B), wherein the acid anhydride Monoe epoxy resin curing agent (C) an acid anhydride in The epoxy resin composition according to claim 2, wherein the group equivalent ratio [acid anhydride group / epoxy group] is a ratio of 0.7 / 1.0 to 1.1 / 1.0. A resin composition for sealing an optical semiconductor, comprising the epoxy resin composition according to claim 1. The composition according to claim 3, which is a material for encapsulating a high-brightness LED element. An optical semiconductor device comprising an optical semiconductor sealed with the epoxy resin composition according to claim 1.