High-refractive high-adhesion epoxy resin composition and sealing material containing the same

Abstract

The present invention provides a high-refractive high-adhesion epoxy resin composition and a sealing material containing the same, which can be applied to various methods such as an inkjet or a dispensing coating method, which injects a low-viscosity liquid to fill a gap and is cured, and has excellent light extraction efficiency at the time of curing, high adhesion, and low outgassing, and can bond or mold an organic or inorganic light-emitting display panel glass member.

Description

TECHNICAL FIELD

[0001] The present invention relates to a high-refractive high-adhesion epoxy resin composition and a sealing material containing the same, and relates to a high-refractive high-adhesion epoxy resin composition and a sealing material containing the same, which can be applied to various methods of injecting a low-viscosity liquid to fill a gap and cure, which has excellent light extraction efficiency at the time of curing, high adhesion, and low outgassing, and which can bond and mold organic or inorganic light-emitting display panel glass parts. BACKGROUND

[0002] With the change in the user's requirements for high integration, thin and compact, and the like of the display, the physical and chemical properties and the use method of the sealing material have also changed. In the past, cathode ray tubes with built-in electron beams and fluorescent substances, field emission displays that emit light through an emitter array, plasma display panels that utilize the photoelectric effect of plasma gas, liquid crystal displays that utilize the electrical arrangement of liquid crystals, and the like have been widely used in the industry, but due to the weight problem of the display itself, the dynamic picture display quality problem, heat generation, burn-in phenomenon, high power consumption, and the like, the performance and lifespan of the displays have varied greatly. In order to improve the various shortcomings of such displays, organic light-emitting display devices have been developed since the late 80s. Organic light-emitting displays have low weight, excellent readability, contrast, and excellent power efficiency and response speed compared to the displays of the past. However, it is also known that the display device also has weaknesses such as a burn-in phenomenon and difficulty in coping with changes in external temperature and humidity.

[0003] In the past, in order to solve such shortcomings, a method of sealing organic light-emitting display elements in a thick glass or transparent inorganic chamber has been used, but this has caused great problems in the usability and operational reliability of the product, and in thinness. The liquid state is most effective when the user freely adjusts the shape of the display, and for this reason, in the present invention, in order to solve the problems currently faced, a material having excellent light extraction efficiency, high adhesion, and low outgassing, which is useful for the development of display elements, has been developed. SUMMARY

[0004] TECHNICAL PROBLEM

[0005] The technical problem to be achieved by the present invention is to provide a high-refractive high-adhesion epoxy resin composition and a sealing material containing the same, which can be applied to various methods of injecting a low-viscosity liquid to fill a gap and cure, which produces a low level of gas at the time of the curing process, has excellent light extraction efficiency at the time of curing, high adhesion, and low outgassing, and which can bond and mold organic or inorganic light-emitting display panel glass parts.

[0006] METHOD FOR SOLVING THE PROBLEM

[0007] The high-refractive high-adhesion epoxy resin composition of the present application for achieving the above object is characterized by containing a high-refractive epoxy resin containing a compound represented by Chemical Formula 1 or Chemical Formula 2, a high-adhesion epoxy resin containing a compound represented by Chemical Formula 3, a dilution epoxy resin, and a curing retarder, and having a film refractive index of 1.61 or more.

[0008] [Chemical Formula 1]

[0009]

[0010] [Chemical Formula 2]

[0011]

[0012] [Chemical Formula 3]

[0013]

[0014] In Chemical Formula 1, the ring represented by a dotted line as a group fused with an adjacent 6-membered ring structure is one of a substituted or unsubstituted C6 to C60 monocyclic aryl group, a substituted or unsubstituted C6 to C60 condensed ring aryl group, a substituted or unsubstituted C6 to C60 aryloxy group, a substituted or unsubstituted C6 to C60 monocyclic heteroaryl group, and a substituted or unsubstituted C6 to C60 condensed ring heteroaryl group,

[0015] In Chemical Formula 2, X is S, O, or C(R 1 )(R 2 ),

[0016] R 1 and R 2 are the same as or different from each other and are each independently selected from the group consisting of hydrogen, deuterium, a halogen, a cyano group, a nitro group, a C1 to C40 alkyl group, a C2 to C40 alkenyl group, a C2 to C40 alkynyl group, a C3 to C40 cycloalkyl group, a heterocycloalkyl group having 3 to 40 atomic nuclei, a C6 to C60 aryl group, a heteroaryl group having 5 to 60 atomic nuclei, a C1 to C40 alkoxy group, a C6 to C60 aryloxy group, a C3 to C40 alkylsilyl group, a C6 to C60 arylsilyl group, a C1 to C40 alkylboron group, a C6 to C60 arylboron group, a C6 to C60 arylphosphane group, a C6 to C60 mono- or di- arylphosphine group, and a C6 to C60 arylamine group, or combine with an adjacent group to form a condensed ring;

[0017] In Chemical Formula 3, G is a glycidyl group-containing organic group, X 1 and X 2each independently hydrogen or methyl, each n is independently an integer of 1 to 10, R is a substituted or unsubstituted C10 to C100 alkylene or alkenylene group,

[0018] In the above Chemical Formula 1 to Chemical Formula 2, each of m and n is independently an integer of 0 to 4, but not 0 at the same time.

[0019] The above high-refractive high-adhesion epoxy resin composition can include a high-refractive epoxy resin 50 to 80 parts by weight, a high-adhesion epoxy resin 5 to 30 parts by weight, a dilution epoxy resin 10 to 50 parts by weight, and a thermal curing agent 0.5 to 5.0 parts by weight.

[0020] The above dilution epoxy resin can be an epoxy resin containing a substituted or unsubstituted alkylene or alkenylene group having 5 to 100 carbon atoms, or an epoxy resin containing an alicyclic group, and more specifically, can be an epoxy resin manufactured by including a compound selected from the group consisting of A-1 to A-3 below.

[0021]

[0022] The above thermal curing agent can be a latent thermal curing agent.

[0023] The above curing retardant can be an amide carboxylic acid.

[0024] Another display element sealing material according to the present invention for achieving the above object can include the above high-refractive high-adhesion epoxy resin composition.

[0025] Effects of the Invention

[0026] According to the present invention, since the composition has excellent optical properties in addition to the excellent processability, electrical, mechanical, and chemical properties of the conventional liquid epoxy material, the user of the composition can obtain operability, productivity, and reliability when using the material. DETAILED DESCRIPTION

[0027] Hereinafter, the epoxy resin composition according to the present invention will be described in more detail.

[0028] Epoxy resins are representative thermosetting resins having a three-dimensional network structure through a curing process from a linear structure, and have excellent properties such as heat resistance, corrosion resistance, adhesive force, insulating property, etc., and thus occupy a very important position in the industrial field as an electrical and electronic material. The main reason why such epoxy resins can be used in the field of electrical and electronic materials is that i) a variety of epoxy resins and curing agents thereof are available, and thus desired properties can be diversely provided; ii) the inherent properties of the resins such as excellent adhesive force, mechanical properties, chemical resistance, etc. are excellent; iii) shrinkage deformation is small upon curing reaction, as compared with other thermosetting resins; iv) in the case of being appropriately formulated into a single-component product, or in the case of using an appropriate curing agent upon being formulated into a two-component product, the shelf life is long, and no by-products are generated upon curing reaction; and iv) transfer molding, coating, casting, manual coating, etc. can be performed, and thus complex shapes can be molded, and thus the encapsulation of electronic parts is suitable.

[0029] Further, in the present invention, by including a high-refractive epoxy resin, a dilution epoxy resin, and a high-adhesion epoxy resin, the inherent mechanical, chemical, and thermal properties of the epoxy resin are maintained, and the light extraction efficiency is excellent upon curing, and thus a high-refractive high-adhesion epoxy resin composition having high adhesive force and low outgassing is obtained.

[0030] (a) high-refractive epoxy resin

[0031] The high-refractive epoxy resin of the present invention is formed by including a monomer represented by Chemical Formula 1 or Chemical Formula 2.

[0032] [Chemical Formula 1]

[0033]

[0034] In the above Chemical Formula 1, the ring represented by a dotted line, which is a group fused with an adjacent 6-membered ring structure, is one of a substituted or unsubstituted C6 to C60 monocyclic aryl group, a substituted or unsubstituted C6 to C60 condensed ring aryl group, a substituted or unsubstituted C6 to C60 aryloxy group, a substituted or unsubstituted C6 to C60 monocyclic heteroaryl group, and a substituted or unsubstituted C6 to C60 condensed ring heteroaryl group,

[0035] Each of m and n is independently an integer of 0 to 4, but is not simultaneously 0.

[0036] [Chemical Formula 2]

[0037]

[0038] In the above Chemical Formula 2, X is S, O, or C(R 1 )(R 2),

[0039] R 1 and R 2 each independently of one another, are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, C1-C40 alkyl, C2-C40 alkenyl, C2-C40 alkynyl, C3-C40 cycloalkyl, heterocycloalkyl having 3 to 40 atomic nuclei, C6-C60 aryl, heteroaryl having 5 to 60 atomic nuclei, C1-C40 alkoxy, C6-C60 aryloxy, C3-C40 alkylsilyl, C6-C60 arylsilyl, C1-C40 alkylboron, C6-C60 arylboron, C6-C60 arylphosphane, C6-C60 mono- or diarylphosphine, and C6-C60 arylamine, or are combined with an adjacent group to form a condensed ring;

[0040] each of the above m and n is independently an integer of 0 to 4, but is not 0 at the same time.

[0041] The content of the high-refractive epoxy resin is preferably 50 to 80 parts by weight, and within the above weight range, a high-refractive property can be obtained.

[0042] The present application has a film refractive index property of at least 1.61 to 1.65 due to the inclusion of the above high-refractive epoxy resin.

[0043] (b) dilution of the epoxy resin

[0044] The dilution epoxy resin of the present application can be an epoxy resin including a compound containing a substituted or unsubstituted alkylene or alkenylene group having 5 to 100 carbon atoms, or a compound containing an alicyclic group, and more specifically, can be an epoxy resin manufactured from a compound selected from the group consisting of A-1 to A-3 below.

[0045]

[0046] The content of the dilution epoxy resin is preferably 10 to 50 parts by weight, in order to adjust the viscosity and ensure heat resistance.

[0047] (c) high adhesion epoxy resin

[0048] The high-adhesion epoxy resin of the present application is a 2-functional epoxy resin represented by Chemical Formula 3 below, and can be used to promote the curing structure of an epoxy composition, relieve stress between substrates of a display, and improve the adhesion of a chip to a substrate.

[0049] [Chemical Formula 3]

[0050]

[0051] In the above Chemical Formula 3, G is an organic group containing a glycidyl group, X 1 and X 2 each independently is hydrogen or a methyl group, each n independently is an integer of 1 to 10, and R is a substituted or unsubstituted C10 to C100 alkylene or alkenylene group.

[0052] As the 2-functional epoxy resin represented by the above Chemical Formula 3, a diglycidyl ether-based 2-functional epoxy resin is preferred, and specifically, at least one selected from the group consisting of a bisphenol F diglycidyl ether type epoxy resin, a bisphenol A diglycidyl ether type epoxy resin, a polyolefin-added bisphenol A diglycidyl ether type epoxy resin, a polyolefin-added bisphenol F diglycidyl ether type epoxy resin, a 1,6-hexanediol diglycidyl ether type epoxy resin, and a 1,4-butanediol diglycidyl ether type epoxy resin can be used.

[0053] In the present application, the content of the above 2-functional epoxy resin is preferably 5 to 30 parts by weight. If the content of the above 2-functional epoxy resin is less than 5 parts by weight, the time for which the product can be used at normal temperature is shortened, and a beneficial effect on high-temperature high-humidity reliability cannot be provided. In addition, the inherent hardness of the composition is excessively increased, and the composition is easily broken, and thus, the adhesion is adversely affected, and thus, this is not preferred.

[0054] (d) heat curing agent

[0055] The high-refractive high-adhesion epoxy resin composition of the present application can include a thermal curing agent. The above thermal curing agent is a thermosetting polymer, and if the epoxy resin is to exhibit its function, a curing agent that matches the same is required, and the inherent properties of the epoxy resin are exhibited by a curing reaction using the curing agent. In the past, amine, acid, and phenol-based curing agents, etc. have been used, and by selective use, adhesion, electrical properties, and resistance to high-temperature high-humidity that are different from other plastic materials have been provided. As a representative example, the reaction of an epoxy resin with an amine curing agent is as follows. The amine curing agent attacks the ring of the epoxy resin to open the same, and after attaching to a specific position, the epoxy-amine molecule that has become large attacks the surrounding epoxy resin to induce a chain reaction. The reaction ends after the amine-containing molecule is almost completely consumed, and the reaction that produces such a dense structure is called a curing reaction. In this reaction, a hydroxyl group is inevitably generated, and although a beneficial effect on adhesion and the usable time of the product is provided, the resistance to moisture is deteriorated, the reliability is unstable, and cracking can occur.

[0056]

[0057] In the present application, it is preferable to use a latent thermal curing agent that initiates direct reaction between the epoxy resin. In this reaction, unlike the above-mentioned epoxy-amine reaction, hydroxyl groups do not appear, and a cured product having a molecular structure like a long fiber can be obtained. Therefore, unlike the conventional epoxy-curing agent reaction, a structure that is advantageous for long-term reliability can be obtained.

[0058]

[0059] As the latent thermal curing agent used herein, any or commercially available curing agent can be used, and specifically, a compound selected from the group consisting of tetradecyl(trihexyl)phosphonium dicyandiamide, 1-butyl-3-methylimidazole tetrafluoroborate, 1-ethyl-3-methylimidazole tetrafluoroborate, 1-ethyl-3-methylimidazole methanesulfonate, tolyl cumene iodine tetra(pentafluorophenyl)borate, Opton CP-66, Opton CP-77 (ADEKA Japan), 2-ethyl-4-methylimidazole tetraphenylborate, tetraphenyl tetraphenylborate, quaternary ammonium borate, (4-acetyloxyphenyl)benzyl(methyl)sulfide tetra(pentafluorophenyl)borate, SI-B2, SI-B3, SI-B3A, SI-B4, SI-B7 (SAMSHIN Chemical Industry).

[0060] In the present application, the content of the latent thermal curing agent is preferably 0.5 to 5.0 parts by weight, more preferably 0.5 to 3.0 parts by weight, and further more preferably 0.5 to 1.5 parts by weight. If the content of the latent thermal curing agent is less than 0.5 parts by weight, there is a possibility that uncured products will be produced, and thus it is not preferable, and if the content is more than 1.5 parts by weight, there is a risk that the usable time at room temperature or high temperature will be shortened, and problems such as generation of heat during curing, and clogging of the dispensing needle tip that sometimes occurs in the dispensing process, will occur, and thus it is not preferable.

[0061] In the present application, a general latent curing agent can be used as long as it exhibits physical and chemical properties instead of the above-mentioned latent thermal curing agent, and a commercially available product can be used. For example, Ajicure MY-24, Ajicure MY-H, Ajicure PN-23, Ajicure PN-H, Ajicure PN-31, Ajicure PN-40, Ajicure PN-50, VDH, VDH-J, AH-154, ADH, DDH, SAH, IDH, SDH, LDH, UDH, Ancamine 2441, Ancamine 2442, Ancamine 2014AS, Technicure LC-80, Technicure LC-100, Technicure LC-214, Technicure MDU-11, Technicure PDU-250, Technicure IPDU-8, Technicure TDU-200, EH-4357, Novacure HX-3721, Novacure HX-3722, Novacure HX-3748, Novacure HX-3741, Novacure HX-3742, Novacure HX-3088, Novacure HX-3613, Novacure HX-3921HPE, Novacure HX-3941HPE, Novacure HX-3932HPE, FXR-1081, FXR-1020, FXR-1060, and the like can be used as the latent curing agent, and they can be used alone or in combination of two or more. These latent curing agents have a microcapsule form in which an epoxy resin surrounds an imidazole curing accelerator, and can promote the curing of the epoxy composition only at a high temperature of 80 to 100°C or less, and can contribute to the storage stability at room temperature.

[0062] (e) additive comprising a cure retarder

[0063] The additive of the present application can include a curing retarder, and the above-mentioned curing retarder can be an amide represented by Chemical Formula 4. For reference, a composition using a cationic initiator can undergo a change in viscosity when stored at 40°C or more, due to the generation of a Lewis acid.

[0064] [Chemical Formula 4]

[0065]

[0066] In Chemical Formula 4, R 3 and R 4which are the same as or different from each other, can be an alkyl group.

[0067] Accordingly, the present application can obtain a high reliability resin with a small change in viscosity by adding the above-mentioned curing retarder.

[0068] For reference, an amine has a high reactivity and, when added to a composition, a high temperature stability is reduced, but an amide carboxylic acid can reduce the amide reactivity by resonance stabilization as follows, thereby being able to inhibit curing by reacting with a Lewis acid through a cationic thermal initiator at 40°C or more and simultaneously inhibit a change in viscosity, thereby being able to improve a high temperature stability.

[0069]

[0070] The epoxy resin composition of the present application can optionally further include an additional additive. The additional additive is used to improve the properties of the epoxy resin composition flowing into the gap between the chip and the substrate, and further prevent voids from occurring in the gap, and for example, BYK 018, BYK 019, BYK 021, BYK 024, BYK 066N, BYK 909, ethoxyethanol, monoether alcohol polyethylene, etc. can be used, but are not limited thereto. The above-mentioned substances can be used alone or two or more kinds thereof can be used in combination.

[0071] The content of the above-mentioned additive can be 0.01 to 1.0 parts by weight. If the content of the additive is less than 0.1 parts by weight, the desired effect cannot be obtained, and if the content is more than 1.0 parts by weight, the flowability is excessively increased and can cause a decrease in physical properties, and thus is not preferred.

[0072] Hereinafter, the present application will be further explained in detail by examples, and the scope of protection of the present application is not limited to the following examples.

[0073] [Example / Comparative Example: Manufacture of epoxy resin composition]

[0074] A high refractive epoxy resin and a dilution epoxy resin, an adhesive epoxy resin were added to a planetary mixer in the components and contents according to Table 1 below, and after stirring at normal temperature and pressure for 2 hours to form a uniform state, a latent thermal curing agent was added in a predetermined amount, and then stirred at normal temperature and pressure for 2 hours. Thereafter, after defoaming under vacuum, a viscous liquid was obtained.

[0075] [Table 1]

[0076]

[0077] (1) D-1: 1-functional liquid epoxy resin, 2-biphenylyl glycidyl ether

[0078] (2) D-2: 2-functional solid epoxy resin, 2,2'-[[l,l'-binaphthalene]-2,2'- diylbis(oxymethylene)]bis-oxirane

[0079] (3) D-3: polyfunctional liquid epoxy resin, fluorene type epoxy compound (EG-200)

[0080] (4) A-2: 2-functional liquid epoxy resin, 2H-Indeno[l,2-b:5,6-b']bisoxirene, octahydro-

[0081] (5) B-1: 2-functional liquid epoxy resin, bisphenol A-bisphenol A diglycidyl ether polymer

[0082] (6) B-2: 2-functional liquid epoxy resin, 2,2-Bis(4-glycidoxyphenyl)propane

[0083] (7) E: additive, amide carboxylic acid compound

[0084] (8) C: latent thermal curing agent, phenyl amine borate

[0085] [Basic evaluation of epoxy resin composition]

[0086] The refractive index (liquid), cured product refractive index (film), viscosity, adhesion, high temperature stability (40°C) of the epoxy resin compositions produced in Examples 1-2 above and the epoxy resin compositions produced in Comparative Examples 1-3 were evaluated, and the results are shown in Table 2 below.

[0087] [Table 2]

[0088]

[0089] 1. Refractive index (liquid): The refractive index of the epoxy resin composition was measured at 25 ± 5°C using an Abbe refractometer

[0090] 2. Refractive index (film): A thin film was joined to a prism, and the refractive index in the thickness direction and the surface direction was measured by changing the incident angle of the laser beam. Measurement was performed using a Metricon 2010 / M

[0091] 3. Viscosity: measured using a Brookfield DV2T viscometer, cone / plate type CPA-51Z spindle at 25±5°C, recording the viscosity after 30 minutes

[0092] 4. Adhesion: after pressure bonding on a 76 mm x 26 mm x 3 mm glass plate on which 0.01 g of the epoxy resin composition was applied, curing in an oven set to 100°C for 60 minutes, the adhesion was measured in a UTM

[0093] 5. Tg: using DSC, after raising the sample to 200°C, cooling to room temperature, and then raising it again to 200°C, the midpoint of the second run of the maximum endothermic peak and the minimum endothermic peak was recorded as Tg

[0094] 6. Weight loss: 10 g of the sample was placed in a vacuum oven, and after 1 hour of vacuuming at 76 cmHg and 25°C, it was calculated according to the calculation method of (initial weight - final weight) / initial weight * 100

[0095] 7. High temperature stability (40°C): in a glass bottle sealed with a rubber stopper, the epoxy resin composition and nitrogen gas were filled, and left at 40±5°C, and the viscosity was measured at 1 day intervals, and if the change rate of the viscosity was 1.2 times or less compared to the initial viscosity, it was recorded

[0096] As shown in Table 2 above, it can be confirmed that the epoxy resin composition manufactured in Examples 1 and 2 of the present application has a film refractive index of 1.61 or more, a suitable viscosity level, high adhesion, a Tg of 90 degrees or more, good weight loss, and good storage stability. In particular, when an amide carboxylic acid compound is included as in Examples 1 and 2, a tendency for improved high temperature stability can be seen. It was confirmed through the above physical property evaluations that the epoxy resin compositions of Examples 1 and 2 can be effectively used as a sealing agent composition for display elements.

[0097] The above detailed description of specific parts of the present application will be apparent to those skilled in the art, and it is obvious that such specific techniques are only preferred embodiments, and the scope of the present application is not limited thereto. Therefore, the actual scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A high-refractive high-adhesion epoxy resin composition, characterized by comprising: a high-refractive epoxy resin; a high-refractive filler; and a curing agent. A high-refractive epoxy resin containing a compound represented by Chemical Formula 1 or Chemical Formula 2 below, a high-adhesion epoxy resin containing a compound represented by Chemical Formula 3 below, a dilution epoxy resin, a curing retardant, and a thermal curing agent, and the curing retardant is an amide carboxylic acid, the thermal curing agent is a latent thermal curing agent, and the dilution epoxy resin contains octahydro-2H-indeno[1,2-b:5,6-b']bicyclooctane, The high-refractive high-adhesion epoxy resin composition contains 50 to 80 parts by weight of the high-refractive epoxy resin, 5 to 30 parts by weight of the high-adhesion epoxy resin, 10 to 20 parts by weight of the dilution epoxy resin, 0.1 to 1.0 parts by weight of the curing retardant, and 0.5 to 1.5 parts by weight of the latent thermal curing agent, has a film refractive index of 1.61 or more, [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] In Chemical Formula 1, the ring represented by the dotted line as a group fused with the adjacent 6-membered ring structure is one of a substituted or unsubstituted C6-C60 monocyclic aryl group, a substituted or unsubstituted C6-C60 condensed ring aryl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 monocyclic heteroaryl group, and a substituted or unsubstituted C6-C60 condensed ring heteroaryl group, In the chemical formula 2, X is S, O or C(R 1 )(R 2 ), R 1 and R 2 each independently of one another, are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, C1-C40alkyl, C2-C40alkenyl, C2-C40alkynyl, C3-C40cycloalkyl, heterocycloalkyl having 3 to 40 atomic nuclei, C6-C60aryl, heteroaryl having 5 to 60 atomic nuclei, C1-C40alkoxy, C6-C60aryloxy, C3-C40alkylsilyl, C6-C60arylsilyl, C1-C40alkylboronyl, C6-C60arylboronyl, C6-C60arylphosphane, C6-C60mono- or diarylphosphine, and C6-C60arylamide, or are combined with an adjacent radical to form a condensed ring; In the chemical formula 3, G is an organic group containing a glycidyl group, X 1 and X 2 each independently is hydrogen or methyl, n each independently is an integer of 1 ~ 10, R is a substituted or unsubstituted C10~C100 alkylene or alkenylene group, In Chemical Formula 1 to Chemical Formula 2, m and n are each independently an integer of 0 to 4, but are not 0 at the same time.

2. A sealing material for a display element, containing the high-refractive high-adhesion epoxy resin composition according to claim 1.

Images