TW202334369A - Sealing material composition and sealing material - Google Patents

Abstract

To provide a sealant composition having excellent water vapor barrier properties at high temperature and high humidity. A sealant composition according to one embodiment comprises an epoxy resin, a plate-like inorganic compound, and a photoinitiator. The plate-like inorganic compound has an average particle size of 0.5 [mu]m or more and less than 5 [mu]m as measured by dynamic light scattering, with an average value of major axis/thickness being 1.3-50. The sealant composition is substantially free of a solvent mainly for dissolving the photoinitiator.

Description

Sealing material composition and sealing material

The present invention relates to a sealing material composition and sealing material.

In recent years, devices using organic thin films, such as photosensors, organic memory elements, display elements, organic transistors, organic thin film solar cells, organic semiconductor elements, communication elements, and the like, have attracted attention. However, electronic devices, especially devices using organic thin films, have a problem of reduced life due to penetration of water or the like. This is because the organic components deteriorate due to moisture, etc., thereby reducing the functionality of the device. Therefore, sealing materials with water vapor barrier properties are required. Here, the water vapor barrier property refers to the property of inhibiting the penetration of moisture from the outside.

As an example of the technology for imparting water vapor barrier properties to a sealing material, the technology described in Japanese Patent Document 1 can be cited. Japanese Patent Document 1 discloses a sealing material composition for organic devices, which contains a plate-shaped inorganic compound dispersed in a matrix polymer in a stacked form.

[Patent Document] Patent document 1: Japanese Patent Application Publication No. 2013-28722

However, the above-mentioned conventional technology still has room for improvement in terms of water vapor barrier properties under high temperature and high humidity. An object of one aspect of the present invention is to realize a sealing material composition with excellent water vapor barrier properties under high temperature and high humidity.

The inventors of the present invention conducted in-depth research to solve the above-mentioned problems, and found that the combination of an epoxy resin, a plate-shaped inorganic compound of a specific shape, and a photoinitiator substantially does not contain a solvent whose main purpose is to dissolve the photoinitiator. The present invention was completed by realizing a sealing material composition with excellent water vapor barrier properties under high temperature and high humidity. One aspect of the present invention includes the following structure. (1) A sealing material composition containing an epoxy resin, a plate-shaped inorganic compound and a photoinitiator; wherein the average particle size of the plate-shaped inorganic compound measured by a dynamic light scattering method is 0.5 μm or more and less than 5 μm, and The average length/thickness ratio is 1.3 to 50; it does not substantially contain a solvent whose main purpose is to dissolve the photoinitiator. (2) The sealing material composition as described in (1), wherein the content of the plate-shaped inorganic compound is 20 to 45% by weight. (3) The sealing material composition as described in (1) or (2), wherein the epoxy resin is an epoxy resin containing a phenol structure. (4) The sealing material composition as described in any one of (1) to (3), wherein the photoinitiator contains PF ₆ ^- , SbF ₆ ^- , (Rf) _n PF _6-n as counter anions ^- or a sulfur or iodine salt of B(C ₆ F ₅ ) ₄ , where Rf is a perfluoroalkyl group and n is a real number from 1 to 6. (5) The sealing material composition according to any one of (1) to (4), which further contains a silane coupling agent having an epoxy group. (6) A sealing material obtained by hardening the sealing material composition described in any one of (1) to (5).

According to one aspect of the present invention, a sealing material composition having excellent water vapor barrier properties under high temperature and high humidity can be provided.

An embodiment of the present invention will be described below, but the present invention is not limited thereto. In this specification, "A to B" indicating a numerical range means "above or equal to A and less than B" unless otherwise specified.

[1. Sealing material composition] A sealing material composition according to an embodiment of the present invention contains an epoxy resin, a plate-shaped inorganic compound and a photoinitiator; wherein the average particle size of the plate-shaped inorganic compound measured by a dynamic light scattering method is greater than or equal to 0.5 μm and Less than 5 μm, and the average length/thickness ratio is 1.3 to 50; it does not substantially contain a solvent whose main purpose is to dissolve the photoinitiator. This makes it possible to provide a sealing material composition having excellent water vapor barrier properties under high temperature and high humidity. In particular, this sealing material composition was surprisingly able to obtain water vapor barrier properties at a high temperature and high humidity of 85° C./85% RH, as shown in the examples described below. The water vapor barrier property can be evaluated using the water vapor transmission rate measured according to the method described in the Examples. Water vapor transmission rate can also be said to indicate moisture permeability.

When the sealing material composition is irradiated with light, the photoinitiator will be decomposed, thereby generating acid. The acid adds to the epoxy groups in the epoxy resin. By carrying out an electrophilic addition reaction (electrophilic addition) of other epoxy groups on the epoxy group, a hardened product of addition polymerization can be obtained. The resulting cured product has a low free volume and excellent water vapor barrier properties due to the π-π stacking of the epoxy resin. In addition, water vapor barrier properties can be further improved by using a plate-shaped inorganic compound. In addition, since the sealing material composition substantially does not contain a solvent whose main purpose is to dissolve the photoinitiator, it can prevent the solvent from entering between the π-π stacks of the epoxy resin and increasing the free volume. Thereby, excellent water vapor barrier properties under high temperature and high humidity can be achieved. Thereby, an increase in the free volume of the sealing material obtained by hardening the sealing material composition is suppressed, and as a result, the penetration of water vapor can be suppressed even under high temperature and high humidity.

In this specification, "sealing material composition" means a composition for obtaining a sealing material. As described below, a sealing material can be obtained by hardening the sealing material composition. The sealing material composition may be an unhardened composition. The sealing material composition can also be said to be a photocurable resin composition. In this specification, "a solvent whose main purpose is to dissolve the photoinitiator" refers to a liquid (including additives) that is not added for the purpose of improving adhesion, compatibility, defoaming, etc.

In this specification, "substantially no solvent" means that the content of the solvent whose main purpose is to dissolve the photoinitiator in the sealing material composition is 0.5% by weight or less. The content of the solvent whose main purpose is to dissolve the photoinitiator in the sealing material composition is 0.5% by weight or less, and can be confirmed by degassing measurement using GC/MS or the like. The content of the solvent whose main purpose is to dissolve the photoinitiator in the sealing material composition is preferably 0.2% by weight or less.

[1-1. Epoxy resin] The sealing material composition contains epoxy resin as a matrix polymerization. Epoxy resin can also be said to be a cationic polymerizable compound. Addition polymerization occurs to the epoxy resin using an acid generated by a photoinitiator to be described later. As a result, a three-dimensional network structure is formed. Utilizing the π-π stacking properties of this three-dimensional network structure, the penetration of water vapor can be suppressed. The sealing material composition may contain only the epoxy resin as a matrix polymer, or may contain a matrix polymer other than the epoxy resin in addition to the epoxy resin, as will be described later.

Examples of the epoxy resin include bisphenol F epoxy resin, bisphenol A epoxy resin, bisphenol E epoxy resin, phenol novolac epoxy resin, alicyclic epoxy resin, and glycidyl amine type. Epoxy resin, hydrogenated bisphenol A type epoxy resin, etc. Alternatively, modified epoxy resins can be used. Examples of the modified epoxy resin include acrylic modified epoxy resin, polybutadiene modified epoxy resin, graft modified epoxy resin, silanized polyepoxy resin, and the like.

Among them, the epoxy resin is preferably an epoxy resin containing a phenol structure. Examples of epoxy resins containing a phenol structure include bisphenol F epoxy resin, bisphenol A epoxy resin, bisphenol E epoxy resin, phenol novolac epoxy resin, and the like. Epoxy resins can be used with hardening accelerators.

[1-2. Plate-shaped inorganic compound] The sealing material composition contains a plate-shaped inorganic compound as a filler. Examples of plate-shaped inorganic compounds include clay, mica, talc, and silicate compounds.

In one embodiment of the present invention, the average particle size of the plate-shaped inorganic compound measured by a dynamic light scattering method is greater than or equal to 0.5 μm and less than 5 μm, and the average length/thickness ratio is 1.3 to 50. The ratio of length to thickness (length/thickness) expresses the aspect ratio. By using a plate-shaped inorganic compound with a high aspect ratio, the moisture transmission path can be extended to suppress the transmission of water vapor. That is, the plate-shaped inorganic compound has a detour function when moisture penetrates into the sealing material.

When the average particle diameter of the plate-shaped inorganic compound measured by the dynamic light scattering method is 0.5 μm or more, it is difficult for the particles to agglomerate again. If the average particle diameter is less than 5 μm, stacking is likely to occur. The average particle size can be measured using the dynamic light scattering method, for example, using DLS-6000 produced by Otsuka Electronics Co., Ltd. of Japan. The average particle diameter is preferably 1 μm or more and less than 5 μm, more preferably 1.5 μm to 4.8 μm, and still more preferably 2 μm to 4.5 μm.

When the average ratio of the major diameter to thickness (major diameter/thickness) of the plate-shaped inorganic compound is 1.3 or more, the plate-shaped inorganic compound is likely to be dispersed in a uniform direction in the sealing material. When the average length/thickness ratio is less than 50, workability is good. The average length/thickness ratio is preferably 1.5 to 25, more preferably 2 to 20.

Hereinafter, the sealing material composition is applied onto a base material or sandwiched between two base materials and then cured. The resulting sealing material will be described as an example. In this sealing material, most of the plate-like inorganic compounds dispersed in the matrix polymer may be oriented parallel to the base material. In addition, the plate-shaped inorganic compound may be dispersed in a stacked state (packing). When the proportion of the plate-like inorganic compound oriented parallel to the base material becomes larger, the gap between the plate-like inorganic compound and the plate-like inorganic compound becomes smaller, or there are fewer gaps. In addition, the stacking state becomes clear, thereby fully exerting the function of detouring moisture, etc.

In the X-ray diffraction pattern of the sealing material, the plate-shaped inorganic compound oriented parallel to the base material exhibits a peak attributed to the (00c) plane (c is a natural number) at the diffraction angle θ. Here, let Ip be the sum of the diffraction intensities of all peaks that can be assigned to the (00c) plane. In addition, Inp is the sum of the diffraction intensities of all peaks attributed to the (abc) plane (either a or b is not 0), that is, all peaks attributed to plate-shaped inorganic compounds that are not oriented parallel to the substrate. In this case, if the ratio between the two (non-parallel orientation ratio α) = Inp/Ip is 0 ≤ α ≤ 0.1, the function of detouring moisture etc. when it passes through the sealing material can be fully exerted. Where c is a natural number, a positive integer, excluding 0 (zero), usually 1 to 20, preferably 1 to 12. When the value of α is 0, it means that all plate-shaped inorganic compounds are oriented parallel to the substrate (Inp=0).

The content of the plate-shaped inorganic compound in 100% by weight of the sealing material composition is preferably 20 to 45% by weight, more preferably 25 to 40% by weight. When the content of the plate-like inorganic compound is 20% by weight or more, the effect of deflecting moisture can be fully exerted. In addition, when the content of the plate-shaped inorganic compound is less than 45% by weight, a relatively sufficient proportion of the matrix polymer can be ensured, so that the properties that the matrix polymer should have, such as adhesion to the substrate, can be fully exerted.

[1-3. Photoinitiator] The sealing material composition contains a photoinitiator as a cationic polymerization initiator. In one embodiment of the present invention, the photoinitiator is, for example, a powdery solid and does not contain a solvent whose main purpose is to dissolve the photoinitiator. A small amount (approximately 0 to 10% by weight) of the solvent used in the manufacturing process of the photoinitiator may remain in the photoinitiator, but even in this case, the photoinitiator remains solid and does not change. In addition, the shape of the photoinitiator may not be powdery, but may also be granular, lumpy, etc.

When classifying preferred photoinitiators based on cations, sulfate salt initiators, iodine salt initiators, etc. can be cited. When classifying preferred photoinitiators based on anions, antimony-based initiators, borate-based initiators, phosphorus-based initiators, etc. can be cited. The photoinitiator is preferably a sulfur or iodine salt containing PF ₆ ^- , SbF ₆ ^- , (Rf) _n PF _6-n ^- or B(C ₆ F ₅ ) ₄ ^- as counter anion. Wherein, the Rf is a perfluoroalkyl group, and the n is a real number from 1 to 6. Examples of cations contained in the photoinitiator include triarylsulfonium, diaryliodonium, and the like.

The content of the photoinitiator in 100% by weight of the sealing material composition is preferably 0.5 to 10% by weight, more preferably 1 to 5% by weight. If the content of the photoinitiator is 0.5% by weight or more, the matrix polymer can be fully cross-linked. In addition, if the content of the photoinitiator is less than 10% by weight, a relatively sufficient proportion of the matrix polymer can be ensured, and therefore the properties that the matrix polymer should have, such as substrate adhesion, can be fully exerted. The solvent used to dissolve the photoinitiator (a solvent whose main purpose is to dissolve the photoinitiator) is not particularly limited as long as it is an organic solvent that does not contain highly reactive functional groups and can dissolve the photoinitiator. Examples of organic solvents include ketone solvents, ester solvents, ether solvents, hydrocarbon solvents, and the like. Examples of ketone solvents include acetone, methyl ethyl ketone, etc., and examples of ester solvents include propylene carbonate, ethyl acetate, and the like.

[1-4.Other ingredients] The sealing material composition may contain other components in addition to the epoxy resin, the plate-shaped inorganic compound and the photoinitiator. Examples of other components include matrix polymers other than epoxy resins and additives (coupling agents, compatibilizers, defoaming agents, etc.). The content of other components in 100% by weight of the sealing material composition may be 0 to 15% by weight, or may be 0 to 10% by weight.

Examples of matrix polymers other than epoxy resin include polyurethane resin, polycarbonate resin, polyacrylate resin, modified olefin resin, polyester resin, and the like.

The sealing material composition may also contain a coupling agent. This can improve adhesion to the base material. Examples of the coupling agent include γ-aminopropyltriethoxyxylan, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane. Oxysilane, vinyltrimethoxysilane, triethoxysilane methacrylate, mercaptotrimethoxysilane, epoxy modified silane, polyurethane modified silane, amine titanate coupling agent, phosphites Titanate coupling agent, pyrophosphate titanate coupling agent, carboxylic acid titanate coupling agent, etc. Among them, epoxy-modified silane, that is, a silane coupling agent with an epoxy group, is preferred. Examples of the silane coupling agent having an epoxy group include: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, etc.

Examples of compatibilizers include: aliphatic diene polymer compatibilizers, polyolefin compatibilizers, alicyclic diene compatibilizers, vinylidene compatibilizers, vinyl acetate and vinyl acetate compatibilizers mixed with Allyl alcohol compatibilizer, etc.

Examples of defoaming agents include: acrylic defoaming agents, low-viscosity silicone defoaming agents, alcohol defoaming agents, fatty acid ester defoaming agents, polyether defoaming agents, etc.

[1-5. Manufacturing method of sealing material composition] For example, a plate-shaped inorganic compound, a photoinitiator, and other components as needed are mixed with a base polymer, and the mixture is mixed using a bead mill, homomixer, ball mill, three-roller mill, kneader, etc. , that is, the above sealing material composition can be obtained. Preferably, the plate-shaped inorganic compound can be dispersed more easily and uniformly by using a ball mill, a three-roller mill, a kneader, etc. for mixing. In addition, when it is difficult to mix a photoinitiator, the photoinitiator may be dissolved in a liquid component among components other than the photoinitiator, and then the various materials described above may be mixed. [1-6. Properties of sealing material composition] The sealing material composition is preferably a liquid having thixotropic properties at 25°C. Preferably, the viscosity at 25°C and shear rate 2 (1/s) is 100 Pa·s or more. In addition, the viscosity at a shear rate of 2 (1/s) is preferably less than 500 Pa·s, and more preferably less than 200 Pa·s. The thixotropy ratio calculated from the ratio of the viscosity at a shear rate of 2 (1/s) and the viscosity at a shear rate of 10 (1/s) is preferably 1.5 to 6, more preferably 1.5 to 3.

[2. Sealing material] The sealing material according to one embodiment of the present invention is obtained by hardening the sealing material composition. The sealing material can also be said to be a hardened product obtained from the sealing material composition. Specifically, the sealing material is obtained by cross-linking the sealing material composition. The cross-linking reaction may be a photohardening reaction. The cumulative light amount used for photohardening can be 1 to 20 J/cm ² . In addition, after photohardening, the cross-linking reaction can be completed by performing heat treatment at, for example, 80 to 100°C x 1 hour.

The packaging material is used for packaging electronic devices such as organic devices. This sealing material shows excellent water vapor barrier properties even under high temperature and high humidity, and therefore can suppress the deterioration of organic devices. In this specification, an organic device refers to a device provided with an organic thin film. Examples of organic devices include organic electroluminescence, photosensors, organic memory elements, display elements, organic transistors, organic thin film solar cells, organic semiconductor elements, communication elements, and the like. More specific examples of organic devices include PM-OLED, AM-OLED, and the like. For example, the sealing material can be used as an end-face sealing material for organic devices. The sealing material may be sandwiched between two substrates provided with organic devices.

The water vapor transmission rate of the sealing material at 85°C/85%RH measured by the method described in the Example is preferably less than 60g/m ² ·day, more preferably less than 55g/m ² ·day, and then updated Preferably, it is less than 50g/m ² ·day.

The glass transition temperature of the sealing material measured by the method described in the examples is preferably greater than 125°C, more preferably equal to or greater than 130°C, still more preferably equal to or greater than 135°C. From the viewpoint of heat resistance, the glass transition temperature of the sealing material is preferably 125°C or higher.

The present invention is not limited to the above-mentioned embodiments, and various changes can be made within the scope indicated in the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the present invention. within the technical scope.

[Evaluation method] [Measurement of Water Vapor Transmission Rate (WVTR) of Hardened Materials] On a Teflon (registered trademark) sheet, the sealing material composition of the Example or Comparative Example was applied to a film thickness of 100 μm using a YD-3 doctor blade manufactured by Japan YOSHIMITSU Seiki Co., Ltd. Next, a constant temperature chamber equipped with a metal halide lamp manufactured by Japan Ushio Electric Co., Ltd. was used, and the UV cumulative amount was 6 J/cm2 and treated at 80° C. for 1 hour. Then, the Teflon (registered trademark) sheet was peeled off to obtain a cured film. The obtained cured film is cut into a predetermined size, and then placed on a moisture-permeable cup made by Japan's Yasuda Seiki Manufacturing Co., Ltd. filled with calcium chloride, and then fixed with a special fixture with screws. The water vapor transmission rate is calculated based on the weight change before placing the cup and after placing it at 85°C/85%RH for 24 hours.

[Measurement of glass transition temperature (Tg) of hardened material] A cured film having a thickness of 100 μm was produced using the sealing material composition of the Example or Comparative Example according to the same procedure described in the above water vapor transmission rate measurement. The obtained cured film was placed in the tension measuring jig of a rheometer manufactured by TA Instruments, and the temperature was raised to 0 to 200°C under the conditions of frequency 1 Hz, strain 0.2% by weight, and heating rate 10°C/min, and bonding was performed. Elasticity measurement. From the obtained data, the maximum point of Tanδ, which is the ratio of storage elastic modulus and loss elastic modulus, was calculated, and the temperature was used as the glass transition temperature.

[Average particle diameter and average length/thickness of plate-shaped inorganic compounds] The average particle size of the plate-shaped inorganic compound was measured by a dynamic light scattering method using DLS-6000 manufactured by Otsuka Electronics Co., Ltd., Japan. In addition, the average length/thickness of the plate-shaped inorganic compound was measured using an electron microscope JST-IT100 manufactured by JEOL Ltd., and the results are as follows. "FG-15" manufactured by Japan Talc Company: average particle size 1.5μm, average length/thickness 20. "P-8" manufactured by Japan Talc Co., Ltd.: average particle diameter 2.8 μm, average length/thickness ratio 30. "P-4" manufactured by Japan Talc Company: average particle size 4.5μm, average length/thickness 30. "P-2" manufactured by Japan Talc Co., Ltd.: average particle diameter 7.0 μm, average length/thickness ratio 30.

[Example 1] 2 wt% of triarylsulfonium salt type antimony photoinitiator ("CPI-110A" manufactured by Japan SanAPro Co., Ltd., powder (solvent-free)) was added to 65 wt% of bisphenol F-type epoxy Resin ("jER806" manufactured by Mitsubishi Chemical Corporation, Japan) was stirred and dissolved at 80°C. Then, 25% by weight of talc as a plate-shaped inorganic compound ("FG-15" manufactured by Nippon Talc Co., Ltd.) and a silane coupling agent as an additive were added to the bisphenol F-type epoxy resin in which the photoinitiator was dissolved. ("KBM-403" manufactured by Japan's Shin-Etsu Chemical Industry Co., Ltd.) 8% by weight, kneaded and dispersed using three rollers. Then, pressure filtration was performed to prepare a sealing material composition.

[Example 2] 2% by weight of triarylsulfonate type antimony photoinitiator ("CPI-110A" manufactured by Japan's SanAPro Co., Ltd., powder (solvent-free)) was added to 73% by weight of bisphenol F-type epoxy resin (Japan's Mitsubishi "jER806" manufactured by a chemical company) and stir at 80°C to dissolve it. Then, 25% by weight of talc ("P-8" manufactured by Nippon Talc Co., Ltd.) as a plate-shaped inorganic compound was added to the bisphenol F-type epoxy resin in which the photoinitiator was dissolved, and the mixture was kneaded and dispersed with three rolls. Then, pressure filtration was performed to prepare a sealing material composition.

[Example 3] 2% by weight of triaryl sulfonate type antimony photoinitiator ("CPI-110A" manufactured by Japan's SanAPro Company, powder (solvent-free)) was added to 40% by weight of bisphenol F-type epoxy resin (Japan's Mitsubishi "jER806" manufactured by Chemical Company) and 20% by weight of phenol novolac epoxy resin ("N-740" manufactured by Japan DIC Company) were added and stirred at 80°C to dissolve. Then, 30% by weight of talc ("P-4" manufactured by Nippon Talc Co., Ltd.) as a plate-shaped inorganic compound and 8% by weight of a silane coupling agent as an additive were added to the epoxy resin in which the photoinitiator was dissolved. ("KBM-403" manufactured by Shin-Etsu Chemical Industry Co., Ltd. of Japan) is kneaded and dispersed using three rollers. Then, pressure filtration was performed to prepare a sealing material composition.

[Example 4] 4% by weight of triaryl sulfonate type borate photoinitiator ("CPI-310B" manufactured by SanAPro Corporation of Japan, powder (solvent-free)) was added to 51% by weight of bisphenol F-type epoxy resin (Japanese "jER806" (manufactured by Mitsubishi Chemical Corporation)) and stir to dissolve at 80°C. Then, 40% by weight of talc ("P-4" manufactured by Nippon Talc Co., Ltd.) as a plate-shaped inorganic compound and 5% by weight of a silane coupling agent as an additive were added to the epoxy resin in which the photoinitiator was dissolved. ("KBM-403" manufactured by Shin-Etsu Chemical Industry Co., Ltd. of Japan) is kneaded and dispersed using three rollers. Then, pressure filtration was performed to prepare a sealing material composition.

[Example 5] 4% by weight of a triarylsulfonate-type antimony photoinitiator ("CPI-110A" manufactured by Japan's SanAPro Company, powder (solvent-free)) was added to 59% by weight of a bisphenol F-type epoxy resin (Japan's Mitsubishi "jER806" manufactured by a chemical company) and 2% by weight of a silane coupling agent as an additive ("KBM-403" manufactured by Shin-Etsu Chemical Industry Co., Ltd.), and stirred to dissolve at 80°C. Then, 35% by weight of talc ("FG-15" manufactured by Nippon Talc Co., Ltd.) as a plate-shaped inorganic compound was added to the epoxy resin in which the photoinitiator was dissolved, and the mixture was kneaded and dispersed using three rollers. Then, pressure filtration was performed to prepare a sealing material composition.

[Comparative example 1] Three-roll kneading was used to disperse 63% by weight of bisphenol F-type epoxy resin ("jER806" manufactured by Japan's Mitsubishi Chemical Corporation) and 25% by weight of talc as a plate-shaped inorganic compound ("FG-15" manufactured by Japan's Talc Corporation). ), 8% by weight of silane coupling agent as an additive ("KBM-403" manufactured by Japan's Shin-Etsu Chemical Industry Co., Ltd.), 4% by weight of triarylsulfonate type liquid antimony photoinitiator ("SP" manufactured by Japan's ADEKA Corporation) -170", containing 50% solvent by weight). Then, pressure filtration was performed to prepare a sealing material composition. In addition, the above-mentioned liquid antimony-based photoinitiator is obtained by dissolving a solid photoinitiator in a solvent with the same weight as the photoinitiator.

[Comparative example 2] A liquid photoinitiator is dispersed using three-roller kneading. The liquid photoinitiator is a powder (solvent-free) of 2% by weight of a triarylsulfonate-type antimony photoinitiator ("CPI-110A" manufactured by SanAPro Corporation of Japan). ) dissolved in 63% by weight of bisphenol F-type epoxy resin ("jER806" manufactured by Mitsubishi Chemical Corporation, Japan), 25% by weight of talc as a plate-shaped inorganic compound ("FG-15" manufactured by Japan Talc Corporation), 8 % by weight of a silane coupling agent ("KBM-403" manufactured by Shin-Etsu Chemical Industry Co., Ltd., Japan) as an additive and 2% by weight of propylene carbonate solvent (manufactured by Tokyo Chemical Industry Co., Ltd., Japan). Then, pressure filtration was performed to prepare a sealing material composition. In Comparative Example 2, the proportion of the propylene carbonate solvent to the total amount of the propylene carbonate solvent and the photoinitiator was 50% by weight.

[Comparative example 3] Three-roll kneading was used to disperse 65% by weight of bisphenol F-type epoxy resin ("jER806" manufactured by Japan's Mitsubishi Chemical Corporation) and 25% by weight of talc as a plate-shaped inorganic compound ("P-2" manufactured by Japan's Talc Corporation). ), 8% by weight of silane coupling agent as an additive ("KBM-403" manufactured by Japan's Shin-Etsu Chemical Industry Co., Ltd.), 2% by weight of triarylsulfonate type liquid antimony photoinitiator ("CPI" manufactured by Japan's SanAPro Corporation) -110A", powder (no solvent)). Then, pressure filtration was performed to prepare a sealing material composition.

[Evaluation results] The evaluation results of the Examples and Comparative Examples are shown in Table 1.

[Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 WVTR(g/m ² ‧day) 85℃85%RH 55 47 45 48 50 Tg(℃) Rheometer 130 150 155 140 135 Comparative example 1 Comparative example 2 Comparative example 3 WVTR(g/m ² ‧day) 85℃85%RH 70 67 61 Tg(℃) Rheometer 120 120 130

First, a comparison was made between Example 1 and Comparative Examples 1 and 2, which had the same composition except for the photoinitiator. As can be seen from Table 1, Example 1 using a solvent-free photoinitiator, Comparative Example 1 using a photoinitiator containing 50% by weight of solvent, and using a photoinitiator in which a powdery photoinitiator is dissolved in a solvent to form a liquid (liquid state When compared with Comparative Example 2 (the solvent content in the photoinitiator: 50% by weight), the water vapor transmittance is reduced, so the water vapor barrier properties under high temperature and high humidity will be improved. In addition, comparing Example 1 with Comparative Examples 1 and 2, the glass transition temperature increased. The same tendency can be seen in the comparison between Examples 4 and 5 and Comparative Examples 1 and 2. Compared with Example 1, since Example 2 does not add a silane coupling agent, and Example 3 adds a phenol novolak type epoxy resin, the glass transition temperature is further increased, and the water vapor transmission rate is further reduced. The average particle diameter of the inorganic compound used in Comparative Example 3 is 5.0 μm or more, so the water vapor transmission rate will increase compared with Example 1.

One aspect of the present invention can be used for sealing materials requiring water vapor barrier properties under high temperature and high humidity.

without

without

Claims (6)

A sealing material composition containing epoxy resin, plate-shaped inorganic compound and photoinitiator; The plate-like inorganic compound has an average particle diameter measured by a dynamic light scattering method of 0.5 μm or more and less than 5 μm, and the average length/thickness ratio is 1.3 to 50; it does not substantially contain the photoinitiator to dissolve it. The main purpose solvent. The sealing material composition of claim 1, wherein the content of the plate-shaped inorganic compound is 20 to 45% by weight. The sealing material composition of claim 1 or 2, wherein the epoxy resin is an epoxy resin containing a phenol structure. The sealing material composition of claim 1 or 2, wherein the photoinitiator contains PF ₆ ^- , SbF ₆ ^- , (Rf) _n PF _6-n ^- or B(C ₆ F ₅ ) ₄ as a counter anion Sulfonium salt or iodonium salt, the Rf is a perfluoroalkyl group, and the n is a real number from 1 to 6. The sealing material composition of claim 1 or 2, which further contains a silane coupling agent having an epoxy group. A sealing material obtained by hardening the sealing material composition according to any one of claims 1 to 5.