WO2005012383A1 - Resin composition - Google Patents

Abstract

A curable resin composition characterized by containing a reactive oligomer or polymer obtained by reacting a compound having two or more epoxy groups per molecule with hydantoin or a derivative thereof which has two secondary amino groups per molecule.

Description

 Description Resin Composition Technical Field

 The present invention relates to a display device, a lighting device, an optical field, an optical information transmission field, an optical information processing field, or the like, which has high transparency, heat resistance, and UV resistance (yellowing resistance). Curable or radiation curable resins.

 Background art

 In recent years, many optical semiconductor devices have been manufactured by encapsulating an optical semiconductor element with an epoxy resin composition, and a repeating unit having a bisphenol A glycidyl ether structure as a main component of such a fiber. Bisphenol A type epoxy resin is widely used.

 On the other hand, at present, semiconductor devices, such as light-emitting diodes having an InGan composition, are becoming shorter in emission wavelength, such as the ultraviolet region and near-ultraviolet region. In order to seal such an ultraviolet-near-ultraviolet light emitting diode, it is not preferable to use a bisphenol A type epoxy resin. The reason is that such a bisphenol A-type epoxy resin turns yellow when an aromatic ring in the molecule absorbs ultraviolet rays. Therefore, there is no aromatic ring as a transparent resin member of the ultraviolet-near-ultraviolet light emitting diode! /, It has been proposed to use hydrogenated bisphenol A type epoxy resin or alicyclic epoxy resin.

 In this regard, epoxy resins having transparency and UV resistance suitable for encapsulating the above-mentioned ultraviolet-near-ultraviolet light emitting diode are all of low molecular weight and liquid at room temperature. This is because the molecular weight of such an epoxy resin can be increased by heating or adding rubric acid or the like, but through such a process, the resin itself discolors or turns yellow, and the transparency of these resins increases. This impairs the feature.

At present, semiconductor package encapsulation using a liquid resin member is based on a method of forming a pattern while extruding from a nozzle, which is generally called a dispenser. A method called potting, in which a thermoset is applied directly to a resin in a resin state, has become mainstream.

 In general, these liquid seals are inferior to semiconductor package seals that use solid resin components in the following ways:

 · Liquid encapsulation has a problem in productivity, especially the production volume per hour is small,

• Liquid resin members generally have lower moisture resistance reliability than solid resin members. In addition, these liquid seals are inferior to transfer molding, which is the main stream of sealing using a solid resin, in the following points:

 • In transfer molding, pressure is applied when the resin is cured, whereas in liquid encapsulation, sealing is performed under no pressure.

 • In transfer molding, the thickness accuracy and outer shape accuracy are specified by the mold, but in liquid encapsulation, resin flow occurs, resulting in poor dimensional accuracy of the sealed product.

Disclosure of the invention

 Therefore, since the ultraviolet-near-ultraviolet light emitting diode is encapsulated with a solid resin, especially for encapsulation by transfer molding, an epoxy that has transparency and UV resistance and is solid at room temperature is used. There is an increasing demand for resin compositions.

 Accordingly, the present invention provides a reactive oligomer or polymer obtained by reacting a compound having two or more epoxy groups in a molecule with a hydantoin or a derivative thereof having two secondary amino groups in a molecule. The present invention provides a curable resin composition comprising:

 By using a compound having two or more epoxy groups and hydantoin or a derivative thereof, it is possible to easily obtain an oligomerized or polymerized epoxy resin by a one-step reaction. The reactive oligomer or polymer of the present invention obtained in this manner has little discoloration of the resin itself and can maintain the optical properties of the starting material because of the small number of production steps.

 The rigid resin composition obtained from the reactive oligomer or polymer of the present invention has high viscosity and good moldability. Further, the cured product obtained from the curable resin composition of the present invention has excellent transparency and UV resistance.

BEST MODE FOR CARRYING OUT THE INVENTION The curable resin composition of the present invention is obtained by reacting a compound having two or more epoxy groups in a molecule with a hydantoin having two secondary amino groups in a molecule or a derivative thereof. Characterized in that it comprises a reactive oligomer or polymer.

 Essentially any epoxy resin can be used as a compound having an epoxy group to produce a reactive oligomer or polymer. Specific examples of the epoxy resin include an alicyclic epoxy resin, a bisphenol A-type epoxy resin, a bisphenol F-type epoxy resin, a bisphenol S-type epoxy resin, a biphenol-type epoxy resin having a biphenyl skeleton, Hydrogenated epoxy resin with hydrogenated aromatic ring, etc., naphthalene ring-containing epoxy resin, dicyclopentagen type epoxy resin with dicyclopentadiene skeleton, phenol novolak type epoxy resin, cresol novolak type epoxy resin, triphenyl methane type epoxy resin Resin, bromine-containing epoxy resin, aliphatic epoxy resin, isocyanuric acid skeleton epoxy resin, hydantoin skeleton epoxy resin, and the like. Here, the “epoxy resin” includes a low molecular weight compound (monomer compound) having only one repeating unit. For example, bisphenol A epoxy resin includes bisphenol A glycidyl ether.

 Among them, hydrogenated epoxy resins, particularly hydrogenated bisphenol A-type epoxy resins, alicyclic epoxy resins having an epoxy group on a ring composed of a saturated aliphatic, and isocyanuric acid skeleton. It is particularly desirable to use epoxy resins or mixtures thereof which have high transparency and UV resistance (yellowing resistance). The hydantoin or a derivative thereof that can be used in the present invention is preferably a compound represented by the general formula (A):

_R2 ^R- °

 γ

 O (A)

[In the formula, represents hydrogen or an alkyl group, and R ₂ represents hydrogen or

Represents a C ₄ alkyl group. ]

Or a derivative thereof. In the above general formula (A), is preferably a hydantoin or a derivative thereof, wherein represents a hydrogen or a methyl group, and R ₂ represents a hydrogen, a methyl group or an isopropyl group. Dimethylhydantoin or methylhydantoin is more preferred as the hydantoin derivative. It is particularly desirable to use 5,5-dimethylhydantoin because of its excellent properties in reactivity, UV resistance and stability. The epoxy compound and the hydantoin or a derivative thereof can be reacted, for example, by melting at a temperature not lower than their respective melting points, adding a catalyst if necessary, and stirring and mixing. The molecular weight of the reactive oligomer or polymer can be controlled by controlling the molar ratio of the compound having an epoxy group to hydantoin or a derivative thereof.

 The reaction product or polymer of the present invention has a high molecular weight and is solid at ordinary temperature. In addition, this reactive oligomer or polymer is more plastic than epoxy monomer, has higher transparency, and is less likely to yellow under UV irradiation. Further, since this reactive oligomer or polymer contains a large amount of nitrogen atoms and is hardly flammable, it has desirable properties for use in an encapsulant / laminate electronic device.

 The rigid resin composition of the present invention is characterized by containing the above reactive oligomer or polymer. The curable resin composition of the present invention preferably contains a curing catalyst that initiates a curing reaction of the resin by an active energy ray such as light or an electron beam or heat. The curable resin composition of the present invention can contain any epoxy resin in addition to the reactive oligomer. Examples of the epoxy resin include, for example, specific examples of the epoxy resin described above as the compound having an epoxy group. One or two or more of these epoxy resins can be used.

In the curable resin composition of the present invention, a so-called curing agent that forms a three-dimensional network structure in the cured product can be used. An acid anhydride curing agent having an acid anhydride group in the molecule, for example, as long as transparency and heat resistance are not impaired, such as tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and hexahydrohydrogen Phthalic anhydride, methylhexahydrophthalic anhydride or hydrogenated methylnadic anhydride A phenolic curing agent having two or more phenol's in the molecule or a molecule thereof, for example, a curing agent such as bisphenol A, phenol nopolak, cresol novolak or naphthol nopolak, or primary amine can be used. Although not intended to be limiting, the curing agent is preferably an acid anhydride since it is difficult to be colored due to transparency, high temperature during hardening and high temperature received from the environment after hardening.

 The molar ratio of the stoichiometric reactive groups between the epoxy resin (referred to as “base agent”) and the curing agent, that is, the ratio (equivalent ratio) between the base agent equivalent and the curing agent equivalent is preferably 100: 60 to 100: 120, more preferably 100: 75 to: L00: 110. When the curing agent equivalent is less than 60 with respect to the main agent equivalent of 100, the composition is hardly cured, the heat resistance of the cured product is reduced even when the composition is cured, or the cured product is hardly cured. The strength may be reduced. Conversely, if the curing agent equivalent exceeds 120, the heat resistance of the cured product may be reduced, the adhesive strength after hardening may be reduced, and the moisture absorption rate of the cured product may increase. .

 Examples of the curing initiator that can be used in the present invention include those that initiate cationic polymerization by light or heat, such as phosphonium salts, odonium salts, sulfonium salts, and silanol aluminum complexes, diazabicycloalkenes and salts thereof, Examples thereof include imidazoles or salts thereof, metal salts of organic acids, quaternary ammonium salts, and phosphines. These are also called curing catalysts, and may be any as long as they cause a curing reaction of the epoxy group.

 Further, other substances can be added to the resin composition of the present invention, if necessary, as long as the object of the present invention is not impaired. Examples of such materials include an ultraviolet absorber, a radical stabilizer, an antioxidant, a flame retardant, a low-elasticity agent, a coloring agent, a diluent, a defoaming agent, and an ion trapping agent.

 In the resin composition of the present invention, an alicyclic epoxy resin or a triazine-based epoxy resin is preferably used in combination. By using these together, the transparency of the cured product can be increased, the glass transition temperature can be adjusted, and the heat resistance can be improved.

Further, it is preferable to use an alicyclic epoxy resin in the resin composition of the present invention. By using this together, the transparency of the cured product is increased and the refractive index is adjusted to be low. can do. In addition, among the alicyclic epoxy resins, those having no ester group in the molecular structure are particularly preferable because of their excellent hydrolysis resistance. For example, hydrogenated bisphenol A type epoxy resin or hydrogenated bisphenol F type epoxy resin, or olefin having a cyclic structure such as bicyclohexene or cyclooctadiene and a carbon-carbon double bond is used as an epoxy resin. What can be obtained by doing so can be listed.

 Finally, examples of the chemical structure of the reactive oligomer or polymer contained in the resin composition of the present invention are shown below.

 For example, when hydrogenated bisphenol A glycidyl ether is used as a hydrogenated bisphenol A type epoxy resin to produce a reactive oligomer or polymer, the reactive oligomer or polymer has the general formula (B):

[Wherein, R ₃ is a moiety obtained by removing a glycidyl group from hydrogenated bisphenol A glycidyl ether, that is,

R ₄ represents hydrogen or an alkyl group, R ₅ represents hydrogen or a C ₄ alkyl group, and 1 represents a number of 0 or more. ]

The structure shown by is taken.

When an alicyclic epoxy resin is used to produce a reactive oligomer or polymer, the reactive oligomer or polymer may be represented by, for example, the general formula (C)

[Wherein, R ₆ is a moiety obtained by removing a cyclic structure from an alicyclic epoxy resin, for example,

One OCH Woo 0— C—

 II

 O

The stands, R ₇ represents hydrogen or ～〇 ₄ alkyl radical, R ₈ represents hydrogen or ~ C ₄ alkyl group, m represents a number of 0 or more. ]

The structure shown by is taken.

 When an epoxy resin having an isocyanuric acid skeleton is used to produce a reactive oligomer or polymer, the reactive oligomer or polymer has, for example, the general formula (D):

[Wherein, R ₉ represents a glycidyl group and 1 ^. It is to display the glycidyl group or Ariru group, R _u represents hydrogen or-alkyl group, R ₁₂ is hydrogen or -. ₄ represents an alkyl group, and _n represents a number of 0 or more. ]

The structure shown by is taken.

Example

 Hereinafter, the present invention will be described specifically with reference to Examples.

 Synthesizing the old ligomer

 Synthesis of oligomer 1

Hydrogenated bisphenol A type epoxy resin (manufactured by Dainippon Ink Co., Ltd., product number "EXA-7015", molecular weight 402) 20.lg, dimethylhydantoin (Mitsui Igaku Fine Fine Co., Ltd.) , Product number 5,5DMH, molecular weight 126) 6.3 g, and 0.074 g of organophosphorus curing catalyst (Nippon Iridaku Kogyo Co., Ltd., product number PX-4ET) in a stainless steel flask The mixture was stirred and mixed for 1 hour while melting at 150 ° C, then taken out of the flask and allowed to cool to room temperature to obtain Oligomer 1 having a melting point of 75 ° C. GPC analysis revealed no monomer peak and oligomerization. When the epoxy equivalent was measured in accordance with JIS K7236, the epoxy equivalent was 264.

 Synthesis of oligomer 2

 Triglycidyl isocyanurate (manufactured by Nissan Chemical Co., Ltd., part number "TEPIC-SJ, molecular weight 297") 29.7 g 'and dimethylhydantoin (manufactured by Mitsui Chemicals, Inc., product number "5,5DMH", molecular weight 126) 6. 3 g was placed in a stainless steel flask and stirred and mixed for 1 hour while melting at 150 ° C., then taken out of the flask and allowed to cool to room temperature to obtain oligomer 2 having a melting point of 70 ° C. GPC analysis revealed no monomer peak and oligomerization. When the epoxy equivalent was measured in accordance with Jis K7236, the epoxy equivalent was 180.

 Synthesis of oligomer 3

 Monoaryl diglycidyl isocyanurate (manufactured by Shikoku Kasei Kogyo Co., Ltd., product number "MA-DGIC", molecular weight 281) 56.2 g, dimethylhydantoin (manufactured by Mitsui Chemicals, Inc., product number "5,5DMH", molecular weight 126) 12.6 g and organophosphorus curing catalyst (Nippon Chemical Industry Co., Ltd., product number "PX-4ET") 0.148 g is put in a stainless steel flask, and stirred and mixed for 1 hour while melting at 150 ° C. After that, the mixture was taken out of the flask and allowed to cool to room temperature to obtain an oligomer 3 having a melting point of 70 ° C. GPC analysis revealed no monomer peak and oligomerization. When the epoxy equivalent was measured in accordance with JIS K7236, the epoxy equivalent was 344.

 Synthesis of oligomer 4

 Alicyclic epoxy resin (manufactured by Daicel Chemical Industries, Ltd., product number "CEL-2021P", molecular weight

25.6 g, dimethylhydantoin (manufactured by Mitsui Chemicals, Inc., product number "5,5DMH", molecular weight 126) 6.3 g, and organophosphorus curing catalyst (manufactured by Nippon Chemical Industry Co., Ltd., product number " PX-4ET ”) Add 0.074 g to a stainless steel flask, stir and mix for 1 hour while melting at 150 ° C, then take out of the flask and allow to cool to room temperature. Oligomer 4 at a point of 70 ° C. was obtained. GPC analysis revealed no monomer peak and oligomerization. When the epoxy equivalent was measured in accordance with jis K7236, the epoxy equivalent was 319.

 Measurement of melt viscosity of oligomer

 The melt viscosities of the oligomers 1-4 of the present invention were measured. For comparison, hydrogenated bisphenol A type epoxy resin (Part No. “EXA-7015”) and cycloaliphatic epoxy resin (Part No. “CEL-2021P”) used for the synthesis of Oligomers 1 and 4 Bisphenol A-type epoxy resin used in the preparation of the resin composition described (Comparative Example 1)

(Part number “1006FS”) was also measured for melt viscosity.

 Melt viscosity was measured using an ICI viscometer at 150 ° C setting.

 (table 1 )

 As shown in Table 1, all of the oligomers 1 to 4 of the present invention have a higher melt viscosity than the epoxy resin for comparison. The oligomers 1 to 4 of the present invention are epoxy resins which are solid at ordinary temperature. Therefore, the oligomers 1 to 4 of the present invention are suitable for use in encapsulation using a solid resin (for example, transfer molding). Preparation of curable resin composition

 Example:! ~ Four

 Using the oligomers 1 to 4 of the present invention, the components other than the curing catalyst were mixed with a disper (manufactured by Tokushu Kagaku Kogyo Co., Ltd.) in an oil path at 80 ° C. at the compounding amount (parts by mass) shown in Table 2 below. After about 1 hour of mixing and mixing, a curing catalyst was added, and the mixture was stirred for about 1 minute, taken out of the flask, and allowed to cool to room temperature to prepare a resin composition.

 Comparative Example 1

 Oligomers of the invention:! A resin composition was prepared in the same manner as in the example, except that the following epoxy resin was used instead of using the following epoxy resins.

The ingredients listed in Table 2 are: Epoxy resin: bisphenol A type epoxy resin (Japan epoxy resin, product number "1006FS", molecular weight 1918)

 Curing agent: Hexahydrophthalic anhydride (HHPA, manufactured by Nippon Rika Chemical Industry Co., Ltd., product number "HHPA", acid anhydride equivalent 154)

 Curing catalyst: Phosphorus organic salt (manufactured by Nippon Chemical Industry Co., Ltd., product number "PX-4ETJ") Measurement of transmittance and yellowness

 The transmittance and yellowness (yellow index) of the cured products obtained from the resin compositions of Examples 1 to 4 and Comparative Example 1 were measured by the following methods. The measurement results are shown in Table 2 below.

 (1) Initial transmittance and yellowness without UV irradiation

 A lmm-thick silicon rubber sheet was used as a spacer, and an epoxy resin composition was sandwiched between stainless steel plates to make a 20 mm x 40 mm cast product. Curing conditions are 120 ° C for 1 hour, and then 150 ° C for 3 hours. The test piece obtained in this way is used to measure the transmittance and yellowness at 800 nm to 250 nm using a system in which an integrating sphere is mounted on a spectrophotometer UV-3100PC manufactured by Shimadzu Corporation. '

(2) Transmittance and yellowness after UV irradiation

A lmm-thick silicon rubber sheet was used as a spacer, and an epoxy resin composition was sandwiched between stainless steel plates to make a 20 mm × 40 mm cast product. The curing conditions are 120 ° C for 1 hour, and then 150 ° C for 3 hours. The test piece obtained in this way is irradiated with UV (20000 1 m) using a high-power UV high-pressure mercury lamp having a peak at 340 nm as a light source. The transmittance and yellowness of the sample obtained after UV irradiation are measured by the above-mentioned method. (Table 2)

 As can be seen from Table 2, the cured products obtained from the resin compositions of Examples 1 to 4 were all compared with the cured product obtained from the resin yarn of Comparative Example 1 after UV irradiation. It is confirmed that the change in light transmittance and yellowness is small and the UV resistance is excellent.

Claims

The scope of the claims 1. Includes a reactive oligomer or polymer obtained by reacting a compound having two or more epoxy groups in the molecule with a hydantoin or derivative thereof having two secondary amino groups in the molecule A curable resin composition comprising: 2. Hydantoin having two secondary amino groups in the molecule or a derivative thereof is represented by the general formula (A):

[In the formula, represents hydrogen or an alkyl group, and R ₂ represents hydrogen or a C ₄ alkyl group. ] 3. The curable resin composition according to claim 1, wherein the curable resin composition is a hydantoin or a derivative thereof.  3. Compounds having two or more epoxy groups in the molecule are hydrogenated bisphenol A type epoxy resins, alicyclic epoxy resins having an epoxy group on a ring composed of a saturated aliphatic group, isocyanur The curable resin composition according to claim 1, wherein the curable resin composition is an epoxy resin having an acid skeleton or a mixture thereof.