Seal components

Abstract

To provide a sealing composition that can form a sealing layer with excellent water vapor intrusion barrier properties and transparency. [Solution] A sealing composition comprising (A) an olefin polymer and (B) calcium oxide, and optionally further comprising (C) semi-calcined hydrotalcite, wherein component (A) comprises an olefin polymer having an acid anhydride group and / or a carboxyl group, and the median diameter of component (B) is 300 nm or less.

Description

[Technical Field]

[0001] The present invention relates to a sealing composition useful for sealing electronic devices and the like. [Background technology]

[0002] Protecting electronic devices such as OLED (Electroluminescence) devices and solar cells from moisture. To protect electronic devices, they are sealed using a sealing layer formed from a sealing composition or sealing sheet. As such compositions or sheets, for example, Patent Document 1 discloses a sealing resin composition containing (A) a polyolefin resin and (B) a metal hydroxide selected from the group consisting of hydrotalcite and semi-calcined hydrotalcite, and a sealing sheet formed therefrom, which possesses both good moisture resistance and transparency. However, hydrotalcite reversibly absorbs and releases moisture. Therefore, in sealing compositions using hydrotalcite, moisture absorbed by the hydrotalcite during the manufacturing or distribution process may be released in the sealing layer of an electronic device formed using the composition, potentially leading to deterioration of the electronic device.

[0003] On the other hand, Patent Document 2 discloses a method for suppressing the degradation of organic EL elements due to moisture incorporated into a resin composition by blending calcium oxide with a encapsulating resin composition containing hydrotalcite. Furthermore, Patent Document 2 describes acrylic resin and epoxy resin as resins that constitute the encapsulating resin composition. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2017 / 057708 [Patent Document 2] International Publication No. 2019 / 167905 [Overview of the project] Problems to be Solved by the Invention

[0005] Calcium oxide is known as a hygroscopic filler. Although a sealing layer formed from a sealing composition obtained by using calcium oxide is excellent in the property of suppressing intrusion of water vapor (sometimes referred to as "water vapor intrusion barrier property" in the present specification), when calcium oxide is contained as a hygroscopic filler in a sealing composition including an olefin polymer, the sealing layer formed from the composition usually loses transparency. To suppress the decrease in transparency, it is conceivable to use fine calcium oxide; however, fine calcium oxide has poor dispersibility, so it has been difficult to produce a composition excellent in transparency in which fine calcium oxide is favorably dispersed in an olefin polymer. Therefore, it has been difficult to achieve both water vapor intrusion barrier property and transparency in a sealing layer formed from a sealing composition including an olefin polymer.

[0006] Further, the refractive indices of the acrylic resin and epoxy resin described in Patent Document 2 are greatly different from the refractive index of semi-calcined hydrotalcite, so a sealing layer formed from a sealing composition including an acrylic resin, an epoxy resin and semi-calcined hydrotalcite is inferior in transparency. On the other hand, the refractive index of an olefin polymer is close to the refractive index of semi-calcined hydrotalcite, so a sealing layer formed from a sealing composition including an olefin polymer and semi-calcined hydrotalcite is excellent in transparency. However, when calcium oxide is added to a sealing composition including an olefin polymer and semi-calcined hydrotalcite to further improve the water vapor intrusion barrier property, the sealing layer formed from the composition usually decreases in transparency. To suppress this decrease in transparency, it is conceivable to use fine calcium oxide; however, fine calcium oxid e is inferior in dispersibility in an olefin polymer. Therefore, it has been difficult to form a sealing layer excellent in both water vapor intrusion barrier property and transparency.

[0007] The present invention has been made in view of the above circumstances, and its objective is to provide a sealing composition that can form a sealing layer with excellent water vapor intrusion barrier properties and transparency. [Means for solving the problem]

[0008] The present invention, which can achieve the above-mentioned objectives, is as follows: [1] The following components (A) and (B): (A) Olefin polymers, and (B) Calcium oxide A sealing composition comprising, (A) Component comprises an olefin polymer having an acid anhydride group and / or a carboxyl group, and (B) A sealing composition having a median diameter of 300 nm or less. [2] The following (C) components: (C) Semi-fired hydrotalcite The sealing composition according to [1] further comprises the following: [3] The encapsulation composition according to [1] or [2], wherein the median diameter of component (B) is 1 nm or more. [4] The sealing composition according to [1], wherein the content of component (B) is 20 to 80% by mass based on 100% by mass of the nonvolatile content of the sealing composition. [5] The sealing composition according to [2], wherein the content of component (B) is 5 to 30% by mass based on 100% by mass of the nonvolatile content of the sealing composition. [6] The sealing composition according to [2] or [5], wherein the content of component (C) is 20 to 70% by mass based on 100% by mass of the nonvolatile content of the sealing composition. [7] The encapsulation composition according to any one of [1] to [6], wherein the olefin polymer having an acid anhydride group and / or a carboxyl group is an olefin polymer having an acid anhydride group. [8] The encapsulation composition according to any one of [1] to [7], wherein component (A) comprises an olefin polymer having an epoxy group. [9] The sealing composition according to any one of [1] to [8], wherein component (A) comprises a liquid olefin polymer.

[10] The sealing composition according to any one of [1] to [9], further comprising a tackifier.

[11] A sealing sheet having a laminated structure comprising a support and a sealing layer formed from any one of the sealing compositions described in [1] to

[10] .

[12] The sealing sheet according to

[11] , wherein the haze of the sealing layer is less than 60%. An electronic device comprising a sealing layer formed from any one of the sealing compositions described in

[13] [1] to

[10] .

[14] A method for producing a sealing composition according to any one of [1] to

[10] , comprising the step of grinding a mixture containing an olefin polymer having an acid anhydride group and / or a carboxyl group, calcium oxide having a median diameter greater than 300 nm, and an organic solvent.

[15] The manufacturing method according to

[14] , further comprising the step of mixing the mixture after grinding with an olefin polymer having epoxy groups. [Effects of the Invention]

[0009] According to the present invention, an adhesive composition can be obtained that can form a sealing layer with excellent water vapor barrier properties and transparency. [Modes for carrying out the invention]

[0010] Sealing composition The sealing composition of the present invention comprises the following components (A) and (B): (A) Olefin polymers, and (B) Calcium oxide Includes, optionally, the following (C) component: (C) Semi-fired hydrotalcite A sealing composition further comprising, (A) Component comprises an olefin polymer having an acid anhydride group and / or a carboxyl group, and (B) The median diameter of component is 300 nm or less.

[0011] The olefin polymer (component (A)) and semi-calcined hydrotalcite (component (C)) used in this invention have similar refractive indices, allowing for the formation of a highly transparent sealing layer from the sealing composition of this invention. Furthermore, by using calcium oxide (component (B)) and semi-calcined hydrotalcite (component (C)) in combination as hygroscopic fillers, the calcium oxide (component (B)) can capture moisture introduced by the semi-calcined hydrotalcite (component (C)), thereby forming a sealing layer with excellent water vapor intrusion barrier properties. Normally, the use of calcium oxide reduces the transparency of the resulting sealing layer. However, in this invention, this reduction in transparency can be suppressed by using calcium oxide (component (B)) with a median diameter of 300 nm or less.

[0012] On the other hand, fine calcium oxide is difficult to disperse well in a sealing composition. However, in the present invention, by using an olefin polymer having acid anhydride groups and / or carboxyl groups, a sealing composition in which fine component (B) is well dispersed can be produced. In this regard, it is presumed that the olefin polymer having acid anhydride groups and / or carboxyl groups functions as a dispersant for fine calcium oxide (component (B)). However, the present invention is not limited to this presumption.

[0013] The components (A) through (C) will be described below in order. Unless otherwise specified in this specification, each component may be used alone or in combination of two or more.

[0014] <(A) component> Component (A) used in the present invention is an olefin polymer. In this specification, "olefin polymer" means a polymer in which the main constituent units are olefin-derived units (hereinafter sometimes abbreviated as "olefin units") (i.e., the amount of olefin units is the largest among all constituent units). In the following, "butene-derived constituent units," etc., which are olefin units, may be abbreviated as "butene units," etc.

[0015] The olefin polymer may be an olefin resin (e.g., propylene-butene copolymer) or an olefin rubber (e.g., butyl rubber, i.e., isobutene-isoprene copolymer). In this specification, "olefin resin" means an olefin polymer that cannot form a rubber elastic body by crosslinking, and "olefin rubber" means an olefin polymer that can form a rubber elastic body by crosslinking.

[0016] As olefins, monoolefins having one olefinic carbon-carbon double bond and / or diolefins having two olefinic carbon-carbon double bonds are preferred. Examples of monoolefins include ethylene, propylene, 1-butene, isobutene ( Examples of α-olefins include isobutylene, 1-pentene, 1-hexene, 1-heptene, and 1-octene. Examples of diolefins include 1,3-butadiene, isoprene, 1,3-pentadiene, and 2,3-dimethylbutadiene.

[0017] The olefin polymer may be a homopolymer or a copolymer. The copolymer may be a random copolymer or a block copolymer. Furthermore, the olefin polymer may be a copolymer of an olefin and a monomer other than an olefin. Examples of olefin copolymers include ethylene-non-conjugated diene copolymer, ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene copolymer, ethylene-butene copolymer, ethylene-propylene-butene copolymer, propylene-butene copolymer, propylene-butene-non-conjugated diene copolymer, isobutene-isoprene copolymer, styrene-isobutene copolymer, and styrene-isobutene-styrene copolymer.

[0018] (Component A1) The present invention is characterized in that component (A) contains an olefin polymer having an acid anhydride group (i.e., a carbonyloxycarbonyl group (-CO-O-CO-)) and / or a carboxyl group (sometimes referred to as "component (A1)" herein). Component (A1) is preferably an olefin polymer having an acid anhydride group. The descriptions and examples of "olefin" and "olefin polymer" in component (A1) are the same as those for component (A) described above.

[0019] (A1) When an olefin polymer having an acid anhydride group is used as component, the concentration of the acid anhydride group in the polymer is preferably 0.05 to 10 mmol / g, more preferably 0.10 to 5 mmol / g. The concentration of the acid anhydride group is obtained from the acid value, which is defined as the number of mg of potassium hydroxide required to neutralize the acid present in 1 g of polymer, in accordance with JIS K 2501.

[0020] (A1) When an olefin polymer having a carboxyl group is used as component, the concentration of the carboxyl group in the polymer is preferably 0.05 to 20 mmol / g, more preferably 0.10 to 10 mmol / g. The concentration of the carboxyl group is obtained from the acid value, which is defined as the number of mg of potassium hydroxide required to neutralize the acid present in 1 g of polymer, in accordance with JIS K 2501.

[0021] (A1) When an olefin polymer having an acid anhydride group and a carboxyl group is used as component, the sum of the concentrations of the acid anhydride group and the carboxyl group in the polymer is preferably 0.05 to 20 mmol / g, more preferably 0.10 to 10 mmol / g.

[0022] (A1) The number-average molecular weight of component (A1) is preferably 1,000 to 1,000,000, more preferably 1,000 to 750,000, from the viewpoint of improving the good coatability of the varnish of the sealing composition, the sealing performance of the formed sealing layer, and the mechanical strength. The number-average molecular weight of each component is measured by gel permeation chromatography (GPC) (polystyrene equivalent). Specifically, the number-average molecular weight by GPC is measured using Shimadzu Corporation's "LC-9A / RID-6A" as the measuring instrument and Showa Denko Corporation's "Shodex" as the column. The K-800P / K-804L / K-804L can be measured using toluene or the like as the mobile phase at a column temperature of 40°C, and the results can be calculated using a calibration curve for standard polystyrene.

[0023] (A1) Component is, for example, (i) an unsaturated compound having an acid anhydride group and / or a carboxyl group (e.g., maleic anhydride) obtained by graft-modifying an olefin polymer under radical reaction conditions, or (ii) an acid anhydride group and / or carboxyl It can be produced by copolymerizing an unsaturated compound having a group with an α-olefin.

[0024] (A1) As components, polymers available from companies such as Toho Chemical Industry Co., Ltd. and Seikoh PMC Co., Ltd. can be used. Examples of such polymers include "HV-300M" (maleic anhydride-modified liquid polybutene) from Toho Chemical Industry Co., Ltd., "ER688" (maleic anhydride-modified liquid polybutene) from Seikoh PMC Co., Ltd., "T-YP279" (maleic anhydride-modified propylene-butene random copolymer) from Seikoh PMC Co., Ltd., "T-YP312" (maleic anhydride-modified propylene-butene random copolymer) from Seikoh PMC Co., Ltd., "ER661" (maleic anhydride-modified isobutene-isoprene random copolymer) from Seikoh PMC Co., Ltd., "T-YP430" (maleic anhydride-modified ethylene-methyl methacrylate copolymer) from Seikoh PMC Co., Ltd., "T-YP956" (maleic anhydride-modified ethylene-propylene-butene random copolymer) from Seikoh PMC Co., Ltd., and "Diacarna 30M" (copolymer of maleic anhydride and α-olefin) from Mitsubishi Chemical Corporation.

[0025] In one embodiment of the present invention, component (A1) is (i) Preferably at least one selected from the group consisting of polybutene having acid anhydride groups and / or carboxyl groups, isobutene-isoprene copolymer having acid anhydride groups and / or carboxyl groups (i.e., butyl rubber), propylene-butene copolymer having acid anhydride groups and / or carboxyl groups, ethylene-methyl methacrylate copolymer having acid anhydride groups and / or carboxyl groups, and ethylene-propylene-butene copolymer having acid anhydride groups and / or carboxyl groups. (ii) More preferably, at least one selected from the group consisting of polybutene having acid anhydride groups and / or carboxyl groups, isobutene-isoprene copolymer having acid anhydride groups and / or carboxyl groups, and propylene-butene copolymer having acid anhydride groups and / or carboxyl groups. (iii) More preferably, at least one selected from the group consisting of polybutene having an acid anhydride group, isobutene-isoprene copolymer having an acid anhydride group, and propylene-butene copolymer having an acid anhydride group. (iv) Particularly preferred is a polybutene having an acid anhydride group.

[0026] The content of component (A1) is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, preferably 45% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less, based on 100% by mass of the nonvolatile content of the sealing composition, from the viewpoint of the dispersibility of fine calcium oxide (component (B)) in the sealing composition.

[0027] ((A2) component) Component (A) preferably contains an olefin polymer having epoxy groups (sometimes referred to as "component (A2)" in this specification). By using component (A1), which has acid anhydride groups and / or carboxyl groups, in combination with component (A2), which has epoxy groups, a crosslinked structure and a strong sealing layer can be formed. The descriptions and examples of "olefin" and "olefin polymer" in component (A2) are the same as those for component (A) described above.

[0028] (A2) The concentration of epoxy groups in component is preferably 0.05 to 10 mmol / g, more preferably 0.10 to 5 mmol / g. The epoxy group concentration is determined from the epoxy equivalent obtained according to JIS K 7236-1995.

[0029] (A2) The number-average molecular weight of component (A2) is important for the good coating properties of the varnish of the sealing composition and the seal that is formed. From the viewpoint of improving the sealing performance and mechanical strength of the sealing layer, the preferred value is 1,000 to 1,000,000, more preferably 2,000 to 750,000, and even more preferably 2,000 to 500,000.

[0030] Component (A2) can be obtained, for example, by (i) graft modification of an olefin polymer under radical reaction conditions with an unsaturated compound having an epoxy group (e.g., glycidyl (meth)acrylate, 4-hydroxybutyl acrylate glycidyl ether, allyl glycidyl ether), or by (ii) copolymerization of an unsaturated compound having an epoxy group with an α-olefin.

[0031] (A2) As components, polymers available from companies such as Sumitomo Chemical Co., Ltd. and Seikoh PMC Co., Ltd. can be used. Examples of such polymers include Sumitomo Chemical's "BONDFAST BF-7M" (ethylene-glycidyl methacrylate copolymer), Sumitomo Chemical's "BONDFAST BF-2B" (ethylene-glycidyl methacrylate-vinyl acetate copolymer), Sumitomo Chemical's "BF-7L" (ethylene-glycidyl methacrylate-methyl acrylate copolymer), Seikoh PMC's "ER829" (glycidyl methacrylate-modified propylene-butene random copolymer), Seikoh PMC's "ER850" (glycidyl methacrylate-modified butyl rubber), and Seikoh PMC's "ER853" (glycidyl methacrylate-modified propylene-butene). Examples include random copolymers, Seikoh PMC's "ER866" (glycidyl methacrylate-modified butyl rubber), Seikoh PMC's "T-YP276" (glycidyl methacrylate-modified propylene-butene random copolymer), Seikoh PMC's "T-YP313" (glycidyl methacrylate-modified propylene-butene random copolymer), and Seikoh PMC's "T-YP431" (glycidyl methacrylate-modified ethylene-methyl methacrylate copolymer).

[0032] (A2) component is, (i) Preferably at least one selected from the group consisting of ethylene-glycidyl methacrylate copolymer, ethylene-glycidyl methacrylate-vinyl acetate copolymer, ethylene-glycidyl methacrylate-methyl acrylate copolymer, propylene-butene copolymer having an epoxy group, isobutene-isoprene copolymer having an epoxy group (i.e., butyl rubber), and ethylene-methyl methacrylate copolymer having an epoxy group. (ii) More preferably, at least one selected from the group consisting of a propylene-butene copolymer having an epoxy group, an isobutene-isoprene copolymer having an epoxy group, and an ethylene-methyl methacrylate copolymer having an epoxy group. (iii) More preferably a propylene-butene copolymer having an epoxy group, and / or an isobutene-isoprene copolymer having an epoxy group, (iv) Particularly preferred is a propylene-butene copolymer having an epoxy group, or an isobutene-isoprene copolymer having an epoxy group.

[0033] (A2) When a propylene-butene copolymer having an epoxy group is used as component, the amount of butene units in the copolymer is preferably 1 to 50% by mass, more preferably 2 to 45% by mass, and even more preferably 3 to 40% by mass, based on the total of propylene units and butene units. The amount of butene units is based on the propylene units and butene units excluding the modified portion (for example, the portion derived from glycidyl (meth)acrylate for introducing the epoxy group).

[0034] (A2) When using an isobutene-isoprene copolymer having an epoxy group (i.e., butyl rubber) as component, from the viewpoint of preventing yellowing of the sealing layer, the amount of isoprene units in the copolymer is preferably 0.1 to 20 units per total of isobutene units and isoprene units. The amount is mass%, more preferably 0.3 to 15 mass%, and even more preferably 0.5 to 10 mass%. The amount of isoprene units is based on isobutene units and isoprene units excluding the modified portion (for example, the portion derived from glycidyl (meth)acrylate for introducing epoxy groups).

[0035] When component (A2) is used, its content is preferably 0.1% by mass or more, more preferably 1% by mass or more, even more preferably 3% by mass or more, preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, relative to 100% by mass of the nonvolatile content of the sealing composition, in order to form a strong sealing layer.

[0036] When using component (A2), it is preferable that the amount of component (A2) having epoxy groups and the amount of component (A1) having acid anhydride groups and / or carboxyl groups be determined by the ratio of the functional groups they possess. Furthermore, from the viewpoint of the dispersibility of component (B), it is preferable to set the ratio of the functional groups they possess so that component (A1) is not completely consumed in the crosslinking formation with component (A2), but a certain amount remains. Although it varies depending on the crosslinking conditions (temperature, time, etc.), the ratio of "(A2) component amount (mol)" to "(A1) component amount (mol) of acid anhydride groups (mol) and carboxyl groups (mol)" is, in one embodiment of the present invention, preferably 100:50 to 100:1500, more preferably 100:60 to 100:1250, even more preferably 100:70 to 100:1000, and particularly preferably 100:80 to 100:900. In another embodiment of the present invention, where the encapsulating composition contains component (C), it is preferably 100:10 to 100:1500, more preferably 100:15 to 100:1250, and even more preferably 100:20 to 100:1000. For example, if component (A1) contains only acid anhydride groups, the "total amount of acid anhydride groups (mol) and carboxyl groups (mol)" refers to the "amount of acid anhydride groups (mol)".

[0037] ((A3) component) Component (A) preferably contains a liquid olefin polymer (sometimes referred to as "component (A3)" in this specification). By using component (A3), good adhesion and flexibility can be imparted to the sealing layer. The descriptions and examples of "olefin" and "olefin polymer" in component (A3) are the same as those for component (A) described above.

[0038] In this invention, "liquid" in "liquid olefin polymer" means that the viscosity at 25°C is 5,000 Pa·s or less. Furthermore, in this invention, "viscosity at 25°C" means the viscosity calculated by multiplying the kinematic viscosity at 25°C, measured by a dynamic viscoelasticity measuring device, by the density. Examples of dynamic viscoelasticity measuring devices include the rheometer manufactured by TA Instruments Corporation (product name: DISCOVERY HR-2).

[0039] In the present invention, liquid olefin polymers having acid anhydride groups and / or carboxyl groups are classified as component (A1). Also in the present invention, liquid olefin polymers having epoxy groups are classified as component (A2). Therefore, component (A3) in the present invention is a liquid olefin polymer other than components (A1) and (A2).

[0040] The viscosity of component (A3) at 25°C is preferably 5 to 5,000 Pa·s, more preferably 10 to 4,000 Pa·s, and even more preferably 20 to 3,000 Pa·ss, from the viewpoint of good adhesion and flexibility of the sealing layer.

[0041] (A3) The number-average molecular weight of component (A3) is preferably 100 to 50,000, more preferably 200 to 30,000, and even more preferably , from the viewpoint of good coating properties of the varnish of the sealing composition. The range is 300 to 20,000.

[0042] (A3) The component can be a commercially available product. Examples of such commercially available products include ENEOS's "HV-300" (liquid polybutene), ENEOS's "HV-1900" (liquid polybutene), ENEOS's "HV-50" (liquid polybutene), ENEOS's "HV-35" (liquid polybutene), Kothari's "950MW" (liquid polybutene), Kothari's "2400MW" (liquid olefin polymer), ENEOS's "H-1900" (liquid polybutene), and ENEOS's "H-6000" (liquid). Liquid polybutene), INEOS's "H-18000" (liquid polybutene), NOF Corporation's "200N" (liquid polybutene), Nippon Soda Co., Ltd.'s "BI-2000" (hydrogenated polybutadiene), Nippon Soda Co., Ltd.'s "BI-3000" (hydrogenated polybutadiene), Nippon Soda Co., Ltd.'s "GI-3000" (hydrogenated polybutadiene), Mitsui Chemicals' "Lucant LX100" (liquid olefin polymer), Mitsui Chemicals' "Lucant LX400" (liquid olefin polymer), Idemitsu Showa Shell Co., Ltd.'s "Poly bd R-45HT" (butadiene-based liquid rubber), Idemitsu Showa Shell Co., Ltd.'s "Poly bd R-15HT" (butadiene-based liquid rubber), Idemitsu Showa Shell Co., Ltd.'s "Poly "ip" (liquid polyisoprene), Nippon Soda Co., Ltd. "B-1000" (liquid polybutadiene), Nippon Soda Co., Ltd. "B-3000" (liquid polybutadiene), Nippon Soda Co., Ltd. "G-3000" (liquid polybutadiene), Kuraray Co., Ltd. "LIR-30" (liquid polyisoprene), Kuraray Co., Ltd. "LIR-390" (liquid polyisoprene), Kuraray Co., Ltd. "LIR-290" (liquid polyisoprene), Kuraray Co., Ltd. "LBR-302" (liquid polybutadiene), Kuraray Co., Ltd. "LBR-305" (liquid polybutadiene), Kuraray Co., Ltd. "LBR-361" (liquid polybutadiene), Kuraray Co., Ltd. "L-SBR-820" (liquid styrene-butadiene random copolymer), Cray Valley Co., Ltd. "Ricon154" (liquid butadiene), Cray Examples include "RICON 184" (liquid styrene-butadiene random copolymer) manufactured by VALLEY.

[0043] Component (A3) is preferably liquid polybutene and / or hydrogenated polybutadiene, and more preferably liquid polybutene.

[0044] When component (A3) is used, its content is preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, based on 100% by mass of the nonvolatile content of the sealing composition, from the viewpoint of good adhesion and flexibility of the sealing layer.

[0045] ((A4) component) Component (A) may include olefin polymers other than components (A1) to (A3), i.e., non-liquid olefin polymers that do not have any acid anhydride groups, carboxyl groups, or epoxy groups (sometimes referred to as "component (A4)" in this specification). The explanations and examples of "olefin" and "olefin polymer" in component (A4) are the same as those for component (A) above.

[0046] In this invention, "non-liquid" in "non-liquid olefin polymer" means that the viscosity at 25°C is greater than 5,000 Pa·s.

[0047] (A4) The number-average molecular weight of component is preferably 10,000 to 1,000,000, more preferably 20,000 to 750,000.

[0048] (A4) The component is, (i) Preferably a propylene-butene copolymer and / or an isobutene-isoprene copolymer (i.e., butyl rubber), (ii) More preferably is an isobutene-isoprene copolymer.

[0049] (A4) When a propylene-butene copolymer is used as component, the amount of butene units in the copolymer is preferably 1 to 50% by mass, more preferably 2 to 45% by mass, and even more preferably 3 to 40% by mass, based on the total of the propylene units and butene units.

[0050] (A4) When using an isobutene-isoprene copolymer (i.e., butyl rubber) as a component, from the viewpoint of preventing yellowing of the sealing layer, the amount of isoprene units in the copolymer is preferably 0.1 to 20% by mass, more preferably 0.3 to 15% by mass, and even more preferably 0.5 to 10% by mass, based on the total of isobutene units and isoprene units.

[0051] The content of component (A4) is preferably 0 to 25% by mass, more preferably 0 to 20% by mass, and even more preferably 0 to 15% by mass, based on 100% by mass of the nonvolatile content of the sealing composition.

[0052] <(B) component> The component (B) used in this invention is calcium oxide with a median diameter of 300 nm or less.

[0053] The median diameter of component (B) is preferably 300 nm or less, more preferably 250 nm or less, from the viewpoint of transparency of the sealing layer, and preferably 1 nm or more, more preferably 5 nm or more, and even more preferably 10 nm or more, from the viewpoint of dispersibility of component (B). The median diameter of component (B) is the median diameter in the volume-based particle size distribution (particle size distribution) created based on the measurement of the particle size of component (B) by dynamic light scattering (JIS Z 8828). Dynamic light scattering is a method for calculating particle size and particle size distribution by analyzing fluctuations corresponding to the speed of Brownian motion from scattered light observed when laser light is irradiated onto particles in a dispersion medium using the photon correlation method. Specifically, this median diameter can be measured and calculated as described in the examples.

[0054] (B) Component may be pulverized calcium oxide with a median diameter exceeding 300 nm, or commercially available calcium oxide with a median diameter of 300 nm or less may be used. Examples of commercially available calcium oxide with a median diameter exceeding 300 nm include "QC-X" from Inoue Lime Industry Co., Ltd., "WAC series" from Sankyo Flour Milling Co., Ltd., and "HAL-G", "HAL-J", "HAL-F", "HAL-O", and "HAL-P" from Yoshizawa Lime Industry Co., Ltd. Examples of commercially available calcium oxide with a median diameter of 300 nm or less include "CaO Nano Powder" from Filgen Inc.

[0055] In one embodiment of the present invention, the content of component (B) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more, with respect to 100% by mass of the nonvolatile content of the sealing composition, from the viewpoint of the water vapor penetration barrier properties of the sealing layer, and preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less, from the viewpoint of the adhesiveness of the sealing layer.

[0056] Furthermore, in another embodiment of the present invention in which the sealing composition contains component (C), the content of component (B) is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, relative to 100% by mass of the nonvolatile content of the sealing composition, and preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less, relative to the tackiness of the sealing layer.

[0057] <(C) component> The component (C) used in this invention is semi-calcined hydrotalcite. Hydrotalcite can be classified into uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite.

[0058] Uncalcined hydrotalcite is, for example, natural hydrotalcite (Mg6Al2(OH) 16is a metal hydroxide having a layered crystal structure as represented by CO3·4H2O, for example, a layer serving as a basic skeleton [Mg 1-X Al X (OH)2]X + and an intermediate layer [(CO3) X / 2 ·mH2O] X- . Uncalcined hydrotalcite is a concept encompassing hydrotalcite-like compounds such as synthetic hydrotalcite. Examples of hydrotalcite-like compounds include those represented by the following formula (I) and the following formula (II).

[0059] [M 2+ 1-x M 3+ x (OH)2] x+ ·[(A n- ) x / n ·mH2O] x- (I) (wherein, M 2+ represents a divalent metal ion such as Mg 2+ , Zn 2+ and the like, M 3+ represents a trivalent metal ion such as Al 3+ , Fe 3+ and the like, A n- represents an n-valent anion such as CO3 2- , Cl - , NO3 - and the like, 0 < x < 1, 0 ≦ m < 1, and n is a positive number.) In formula (I), M 2+ is preferably Mg 2+ , M 3+ is preferably Al 3+ , and A n- is preferably CO3 2- .

[0060] M 2+ x Al2(OH) 2x+6-nz (A n- ) z ·mH2O (II) (wherein, M 2+ is Mg 2+ , Zn2+ This represents divalent metal ions such as A. n- CO3 2- Cl - NO3 - This represents an n-valence anion, where x is a positive number greater than or equal to 2, z is a positive number less than or equal to 2, m is a positive number, and n is a positive number. In formula (II), M 2+ Preferably Mg 2+ A n- Preferably CO3 2- That is the case.

[0061] Partially calcined hydrotalcite refers to a metal hydroxide with a layered crystalline structure obtained by calcining uncalcined hydrotalcite, in which the amount of interlayer water is reduced or eliminated. "Interlayer water," when explained using the chemical formula, refers to "H2O" as shown in the chemical formula of the uncalcined natural hydrotalcite and hydrotalcite-like compounds mentioned above.

[0062] On the other hand, calcined hydrotalcite refers to a metal oxide having an amorphous structure obtained by calcining uncalcined or semi-calcined hydrotalcite, in which not only intercalated water but also hydroxyl groups have disappeared through condensation dehydration.

[0063] Uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by their saturation water absorption rates. The saturation water absorption rate of semi-calcined hydrotalcite is 1% by mass or more and less than 20% by mass. On the other hand, the saturation water absorption rate of uncalcined hydrotalcite is less than 1% by mass, and the saturation water absorption rate of calcined hydrotalcite is 20% by mass or more.

[0064] "Saturation water absorption rate" refers to the rate of mass increase relative to the initial mass when a 1.5g sample (e.g., semi-calcined hydrotalcite) is weighed using a balance, its initial mass is measured, and then it is left standing for 200 hours in a small environmental test chamber (SH-222, manufactured by ESPEC Corporation) set to atmospheric pressure, 60°C, and 90% RH (relative humidity). The formula is as follows (i): Saturated water absorption rate (mass%) = 100 × (mass after moisture absorption - initial mass) / initial mass (i) It can be calculated using this method.

[0065] The saturation water absorption rate of semi-calcined hydrotalcite is preferably 3% by mass or more and less than 20% by mass, more preferably 5% by mass or more and less than 20% by mass.

[0066] Furthermore, uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by their thermogravimetric analysis rates. The thermogravimetric analysis rate for semi-calcined hydrotalcite is less than 15% by mass at 280°C, and its thermogravimetric analysis rate for semi-calcined hydrotalcite is 12% by mass or more at 380°C. On the other hand, the thermogravimetric analysis rate for uncalcined hydrotalcite is 15% by mass or more at 280°C, and the thermogravimetric analysis rate for calcined hydrotalcite is less than 12% by mass at 380°C.

[0067] Thermogravimetric analysis can be performed using a Hitachi High-Tech Science TG / DTA EXSTAR6300. 5 mg of hydrotalcite is weighed into an aluminum sample pan, and the pan is left open without a lid. The analysis is performed under a nitrogen flow rate of 200 mL / min, and the temperature is increased from 30°C to 550°C at a heating rate of 10°C / min. The thermogravimetric loss rate is calculated using the following formula (ii): Thermogravimetric reduction rate (mass%) It can be calculated as (ii) = 100 × (mass before heating - mass when the predetermined temperature is reached) / mass before heating.

[0068] Furthermore, uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by the peaks and relative intensity ratios measured by powder X-ray diffraction. Semi-calcined hydrotalcite shows a peak split into two around 8-18° 2θ by powder X-ray diffraction, or a peak with a shoulder formed by the combination of two peaks. The relative intensity ratio (low-angle diffraction intensity / high-angle diffraction intensity) between the diffraction intensity of the peak or shoulder appearing at the low angle (=low-angle diffraction intensity) and the diffraction intensity of the peak or shoulder appearing at the high angle (=high-angle diffraction intensity) is 0.001-1,000. On the other hand, uncalcined hydrotalcite has only one peak around 8-18°, or the relative intensity ratio of the diffraction intensity of the peak or shoulder appearing at the low angle and the peak or shoulder appearing at the high angle is outside the aforementioned range. Calcined hydrotalcite does not have a characteristic peak in the 8°-18° region, but has a characteristic peak at 43°. Powder X-ray diffraction measurements were performed using a powder X-ray diffractometer (PANalytical, Empyrean) under the following conditions: counter cathode CuKα (1.5405 Å), voltage: 45 V, current: 40 mA, sampling width: 0.0260°, scanning speed: 0.0657° / s, and measurement diffraction angle range (2θ): 5.0131~79.9711°. Peak search was performed using the peak search function of the software attached to the diffractometer, under the conditions of "minimum significance: 0.50, minimum peak tip: 0.01°, maximum peak tip: 1.00°, peak base width: 2.00°, method: minimum value of the second derivative".

[0069] The BET specific surface area of ​​semi-calcined hydrotalcite is 1 to 250 m². 2 / g is preferred, 5-200m 2 / g is more preferable. These BET specific surface areas can be calculated using the BET method by adsorbing nitrogen gas onto the sample surface using a specific surface area measuring device (Macsorb HM Model 1210, manufactured by Mountec) and then using the BET multipoint method.

[0070] The particle size of the semi-calcined hydrotalcite is preferably 1 to 1,000 nm, and more preferably 10 to 800 nm. These particle sizes are determined by laser diffraction scattering particle size distribution measurement (JIS Z This is the median diameter of the particle size distribution when the particle size distribution is created on a volume basis according to 8825).

[0071] Semi-calcined hydrotalcite can be used after surface treatment with a surface treatment agent. Examples of surface treatment agents that can be used include higher fatty acids, alkylsilanes, and silane coupling agents, among which higher fatty acids and alkylsilanes are particularly suitable. It is suitable. One or more surface treatment agents can be used.

[0072] Semi-calcined hydrotalcite can be commercially available. Examples of such commercially available products include "DHT-4C" and "DHT-4A-2" manufactured by Kyowa Chemical Industry Co., Ltd.

[0073] The content of component (C) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more, relative to 100% by mass of the nonvolatile content of the sealing composition, from the viewpoint of the water vapor penetration barrier properties of the sealing layer, and preferably 70% by mass or less, more preferably 65% ​​by mass or less, and even more preferably 60% by mass or less, from the viewpoint of the adhesiveness of the sealing layer.

[0074] <Other ingredients> The sealing composition of the present invention may contain components other than components (A) to (C) (hereinafter sometimes referred to as "other components"), as long as they do not impair the effects of the present invention. Examples of other components include tackifiers, metal complexes, antioxidants, curing accelerators, and plasticizers. These may be used individually or in combination of two or more. Tackifiers and the like will be described in order below.

[0075] (Adhesion agent) Tackifiers are components that impart tackiness to sealing compositions. Examples of tackifiers include rosin resins, terpene resins, modified terpene resins (hydrogenated terpene resins, terpene-phenol copolymer resins, aromatically modified terpene resins, etc.), petroleum resins (aliphatic petroleum resins, hydrogenated petroleum resins, alicyclic petroleum resins, aromatic petroleum resins, copolymer petroleum resins), coumarone-indene resins, alkylphenol resins, xylene resins, and the like.

[0076] Commercially available tackifiers can be used. Examples of such commercially available products include: Rosin-based resins such as Pine Crystal ME-H, Pine Crystal ME-D, Pine Crystal ME-G, Pine Crystal KR-85, Pine Crystal KE-311, Pine Crystal KE-359, and Pine Crystal. Examples include D-6011, Pine Crystal PE-590, Pine Crystal KE-604, and Pine Crystal PR-580 (all manufactured by Arakawa Chemical Industries, Ltd.).

[0077] Examples of terpene resins include YS Resin PX1000, YS Resin PX1150, YS Resin PX1150N, YS Resin PX1250, YS Resin TH130, YS Resin TR105, YS Resin LP, and YS Resin CP (all manufactured by Yasuhara Chemical Co., Ltd.).

[0078] Examples of hydrogenated terpene resins include the Clearon P, Clearon M, and Clearon K series (all manufactured by Yasuhara Chemical Co., Ltd.).

[0079] Examples of terpene phenol copolymer resins include YS Polystar 2000, Polystar U, Polystar T, Polystar S, and Mighty Ace G (all manufactured by Yasuhara Chemical Co., Ltd.).

[0080] Examples of aromatically modified terpene resins include YS Resin TO85, YS Resin TO105, YS Resin TO115, and YS Resin TO125 (all manufactured by Yasuhara Chemical Co., Ltd.).

[0081] Examples of hydrogenated petroleum resins include the Escorez 5300 series and 5600 series (both manufactured by ExxonMobil); T-REZ OP501, T-REZ PR803, T-REZ HA085, T-REZ HA103, T-REZ HA105, TR Examples include EZ HA125 (both hydrogenated dicyclopentadiene petroleum resins, manufactured by ENEOS Corporation); Quintone 1325, Quintone 1345 (both manufactured by Nippon Zeon Corporation); iMarb S-100, iMarb S-110, iMarb P-100, iMarb P-125, iMarb P-140 (all hydrogenated dicyclopentadiene petroleum resins, manufactured by Idemitsu Kosan Co., Ltd.); Alcon P-90, Alcon P-100, Alcon P-115, Alcon P-125, Alcon P-140, Alcon M-90, Alcon M-100, Alcon M-115, Alcon M-135, TFS13-030 (all manufactured by Arakawa Chemical Industries, Ltd.).

[0082] Examples of aromatic petroleum resins include ENDEX155 (manufactured by Eastman Corporation); Neopolymer L-90, Neopolymer 120, Neopolymer 130, Neopolymer 140, Neopolymer 150, Neopolymer 170S, Neopolymer 160, Neopolymer E-100, Neopolymer E-130, Neopolymer M-1, Neopolymer S, Neopolymer S100, Neopolymer 120S, Neopolymer 130S, Neopolymer EP-140 (all manufactured by ENEOS Corporation); Petocol LX, Petocol 120, Petocol 130, Petocol 140 (all manufactured by Tosoh Corporation); T-REZ RB093, T-REZ RC100, T-REZ RC115, T-REZ RC093, T-REZ RE100 (all manufactured by ENEOS Corporation).

[0083] Examples of copolymerized petroleum resins include T-REZ HB103, T-REZ HB125, T-REZ PR801, T-REZ PR802, and T-REZ RD104 (all manufactured by ENEOS Corporation); Petrotac 60, Petrotac 70, Petrotac 90, Petrotac 90HS, Petrotac 90V, and Petrotac 100V (all manufactured by Tosoh Corporation); and Quintone D100 (manufactured by Nippon Zeon Corporation).

[0084] The softening point of the tackifier is preferably 50 to 200°C, more preferably 90 to 180°C, and even more preferably 100 to 170°C, from the viewpoint of the heat resistance of the sealing composition. The softening point is measured by the ring-and-ball method in accordance with JIS K2207.

[0085] When a tackifier is used, its content is preferably 1 to 50% by mass, more preferably 2 to 40% by mass, and even more preferably 5 to 30% by mass, based on 100% by mass of the non-volatile content of the sealing composition, from the viewpoint of the tackiness and sealing properties of the sealing layer.

[0086] (Metal complexes) (C) To better disperse component C in the encapsulation composition, a metal complex may be used in which a bidentate ligand (hereinafter sometimes referred to as "oxygen-bidentate ligand") in which both coordinating atoms are oxygen atoms and a monodentate ligand (hereinafter sometimes referred to as "oxygen-monodentate ligand") in which one coordinating atom is an oxygen atom are bonded to the central metal.

[0087] The metal complex is preferably of the following formula (1):

[0088] [ka]

[0089] [In formula (1), M represents metals with a valent or higher valency. R1 and R3 independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an alkenyloxy group, an aryl group, or an aralkyl group. R2 represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, alkoxy group, alkenyloxy group, alkoxycarbonyl group, aryl group, or aralkyl group. X represents a monosequence ligand, In equation (1), the solid line between the oxygen atom (O) and M in the brackets [ ] represents a covalent bond. In equation (1), the dashed line between the oxygen atom (O) and M in the brackets [ ] represents a coordinate bond, and m represents 3 or 4, and n represents an integer between 0 and 4, where m ≥ n. This is a metal complex represented by (hereinafter sometimes abbreviated as "metal complex (1)"). Metal complex (1) may be used alone or in combination of two or more types.

[0090] In formula (1) above, M is preferably a metal from Group 4 or Group 13 of the periodic table, and more preferably aluminum, titanium, or zirconium.

[0091] Examples of halogen atoms in this specification include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0092] In this specification, alkyl groups may be linear or branched. The number of carbon atoms in an alkyl group (excluding alkyl groups in long-chain alkyl (meth)acrylates) is preferably 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 6. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, 1-ethylpropyl, hexyl, isohexyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, and 2-ethylbutyl groups. Alkyl groups may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0093] In this specification, the alkenyl group may be linear or branched. The number of carbon atoms in the alkenyl group is preferably 2 to 20. Examples of alkenyl groups include ethenyl group (i.e., vinyl group), 1-propenyl group, 2-propenyl group, 2-methyl-1-propenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 3-methyl-2-butenyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 4-pentenyl group, 4-methyl-3-pentenyl group, 1-hexenyl group, 3-hexenyl group, and 5-hexenyl group. The alkenyl group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0094] In this specification, the alkynyl group may be linear or branched. The number of carbon atoms in the alkynyl group is preferably 2 to 10, more preferably 2 to 6. Examples of alkynyl groups include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 1-hexynyl, 2-hexynyl, 3-hexynyl, 4-hexynyl, 5-hexynyl, and 4-methyl-2-pentynyl. The alkynyl group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0095] In this specification, the number of carbon atoms in the aryl group is preferably 6 to 18, more preferably 6 to 14. Examples of aryl groups include phenyl, 1-naphthyl, and 2-naphthyl groups. Examples include groups such as 1-anthryl, 2-anthryl, and 9-anthryl. The aryl group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, optionally substituted alkyl groups, optionally substituted alkenyl groups, optionally substituted alkynyl groups, and optionally substituted amino groups.

[0096] In this specification, the number of carbon atoms in the aralkyl group is preferably 7 to 16. Examples of aralkyl groups include benzyl groups, phenethyl groups, naphthylmethyl groups, and phenylpropyl groups. The aralkyl group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0097] In this specification, examples of amino groups that may have substituents include amino groups, mono- or di-alkylamino groups (e.g., methylamino group, dimethylamino group, ethylamino group, diethylamino group, propylamino group, dibutylamino group), mono- or di-cycloalkylamino groups (e.g., cyclopropylamino group, cyclohexylamino group), mono- or di-arylamino groups (e.g., phenylamino group), mono- or di-aralkylamino groups (e.g., benzylamino group, dibenzylamino group), heterocyclic amino groups (e.g., pyridylamino group), and the like.

[0098] In this specification, the description of alkyl groups in alkoxy groups (i.e., alkyloxy groups) is the same as the description of alkyl groups above. The alkoxy group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0099] In this specification, the description of the alkenyl group in the alkenyloxy group is the same as the description of the alkenyl group above. The alkenyloxy group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0100] In this specification, the description of the alkyl group in an alkoxycarbonyl group (i.e., an alkyloxycarbonyl group) is the same as the description of the alkyl group above. The alkoxycarbonyl group may have substituents. Examples of substituents include halogen atoms, hydroxyl groups, and optionally substituted amino groups.

[0101] Examples of monodentate ligands represented by X in equation (1) include alkoxy anions (RO - )(In the above formula, R represents an organic group), carboxylate anion (RCOO - Examples include oxo(O), where R represents an organic group.

[0102] Alkoxy anions are RO - (In the above formula, R represents an organic group). The organic group R may be either an aliphatic group or an aromatic group. Furthermore, the aliphatic group may be either a saturated aliphatic group or an unsaturated aliphatic group. The number of carbon atoms in the organic group R is preferably 1 to 20, more preferably 6 to 18, and particularly preferably 8 to 14. Alkoxy anion (RO - Examples of these include methoxide, ethoxide, propoxide, isopropoxide, butoxide, isobutoxide, sec-butoxide, tert-butoxide, pentyl oxide, hexyl oxide, phenoxide, and 4-methylphenoxide.

[0103] Carboxylate anions are RCOO - (In the above formula, R represents an organic group). The organic group R may be either an aliphatic group or an aromatic group. Furthermore, the aliphatic group may be either a saturated aliphatic group or an unsaturated aliphatic group. The number of carbon atoms in the organic group R is preferably 1 to 20. More preferably 6 to 18, and particularly preferably 8 to 14. Carboxylate anion (RCOO - Examples of carboxylic acids include carboxylate anions corresponding to carboxylic acids such as acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, octicic acid, nonanoic acid, decanoic acid, dodecanoic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, and benzoic acid.

[0104] Examples of polydentate ligands represented in the brackets [ ] in formula (1) include acetylacetone, 3-methyl-2,4-pentanedione, acetylacetaldehyde, 2,4-hexanedione, 2,4-heptanedione, 5-methyl-2,4-hexanedione, 5,5-dimethyl-2,4-hexanedione, benzoylacetone, benzoylacetophenone, salicylaldehyde, 1,1,1-trifluoroacetylacetone, 1,1,1,5,5,5-hexafluoroacetylacetone, 3-methoxy-2,4-pentanedione, 3-cyano-2,4-pentanedione, 3-nitro-2,4-pentanedione, 3-chloro-2,4-pentanedione, acetoacetic acid, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, salicylic acid, methyl salicylate, malonic acid, dimethyl malonate, and diethyl malonate. When coordinated to a central metal, a polydentate ligand takes on a structure from which one or more protons have been removed.

[0105] Specific examples of metal complexes (1) in which M is aluminum include aluminum diisopropylate monosec-butyrate, aluminum trisec-butyrate, aluminum triisopropylate, aluminum triethylate, aluminum tris(acetylacetonate), aluminum bis(ethylacetoacetate)mono(acetylacetonate), aluminum tris(ethylacetoacetate), aluminum octadecenylacetoacetate diisopropylate, aluminum ethylacetoacetate diisopropylate, aluminum ethylacetoacetate di-n-butyrate, aluminum propylacetoacetate diisopropylate, aluminum n-butylacetoacetate diisopropylate, aluminum tris(ethylacetoacetate), aluminum mono(acetylacetonate)bis(ethylacetoacetate), and aluminum tris(acetylacetonate).

[0106] Specific examples of metal complexes (1) where M is titanium include tetraisopropyl titanate, tetran-butyl titanate, tetraoctyl titanate, tetratert-butyl titanate, tetrastearyl titanate, titanium tetraacetylacetonate, titanium octylene glycolate (also known as bis(2-ethylhexyloxy)bis(2-ethyl-3-oxohexyloxy)titanium(IV)), titanium diisopropoxide bis(ethylacetoacetate), and titanium Examples include ammonium triisopropoxide, titanium dinormal butoxide bis(2,4-pentanedione), titanium diisopropoxide bis(tetramethylheptanedione), titanium diisopropoxide bis(ethylacetate), titanium(IV) tetra(methylphenolate), titanium oxide bis(2,4-pentanedione), monoisopropoxytitanium triisostearate, and diisopropoxytitanium diisostearate.

[0107] Specific examples of metal complexes (1) where M is zirconium include zirconium tetran-n-propoxide, zirconium tetran-n-butoxide, zirconium tetra(acetylacetonate), zirconium allyl acetate triisopropoxide, zirconium din-n-butoxide bis(2,4-pentanedione), zirconium diisopropoxide bis(2,4-pentanedione), zirconium diisopropoxide bis(tetramethylheptanedione), zirconium diisopropoxide bis(ethylacetoacetate), zirconium butoxide (acetylacetate) bis(ethylacetoacetate) Examples include toacetate, zirconium tributoxide monoacetylacetonate, zirconium octoate, zirconium stearate, trin-normal butoxyzirconium monooctylate, and trin-normal butoxyzirconium monostearate.

[0108] When a metal complex is used, its content is preferably 0.01 to 3% by mass, more preferably 0.05 to 2.5% by mass, and even more preferably 0.10 to 2% by mass, based on 100% by mass of the nonvolatile content of the sealing composition, from the viewpoint of the dispersibility of component (C).

[0109] (Antioxidant) In the present invention, there are no particular limitations on the antioxidant, and known antioxidants can be used. When an antioxidant is used, its content is preferably 0.01 to 5% by mass, more preferably 0.05 to 2.5% by mass, and even more preferably 0.10 to 2% by mass, based on 100% by mass of the nonvolatile content of the sealing composition.

[0110] (Curing accelerator) In the present invention, a curing accelerator may be used to promote the crosslinking reaction between the acid anhydride group and / or carboxyl group of component (A1) and the epoxy group of component (A2). Examples of curing accelerators include imidazole compounds, tertiary and quaternary amine compounds, dimethylurea compounds, and organophosphine compounds.

[0111] Examples of imidazole compounds include 1H-imidazole, 2-methylimidazole, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-undecylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-undecylimidazole, 2-phenyl-4,5-bis(hydroxymethyl)imidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 2-phenylimidazole, 2-dodecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole. Specific examples of imidazole compounds include Cureazole 2MZ, 2P4MZ, 2E4MZ, 2E4MZ-CN, C11Z, C11Z-CN, C11Z-CNS, C11Z-A, 2PHZ, 1B2MZ, 1B2PZ, 2PZ, C17Z, 1.2DMZ, 2P4MHZ-PW, 2MZ-A, and 2MA-OK (all manufactured by Shikoku Chemicals Co., Ltd.).

[0112] There are no particular restrictions on tertiary and quaternary amine compounds, but examples include quaternary ammonium salts such as tetramethylammonium bromide, tetrabutylammonium bromide, and triethylmethylammonium 2-ethylhexanoate; diazabicyclo compounds such as DBU (1,8-diazabicyclo[5.4.0]undecene-7), DBN (1,5-diazabicyclo[4.3.0]nonene-5), DBU-phenol salt, DBU-octylate, DBU-p-toluenesulfonate, DBU-formate, and DBU-phenol novolac resin salt; tertiary amines such as benzyldimethylamine, 2-(dimethylaminomethyl)phenol, and 2,4,6-tris(dimethylaminomethyl)phenol (TAP) or their salts, and dimethylurea compounds such as aromatic dimethylurea and aliphatic dimethylurea.

[0113] Examples of dimethylurea compounds include aromatic dimethylureas such as DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) and U-CAT3512T (manufactured by Sunapro Co., Ltd.), and aliphatic dimethylureas such as U-CAT3503N (manufactured by Sunapro Co., Ltd.). Among these, aromatic dimethylureas are preferred due to their curability.

[0114] Examples of organic phosphine compounds include triphenylphosphine, tetraphenylphosphonium tetra-p-tolylborate, tetraphenylphosphonium tetraphenylborate, tri-tert-butylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and triphenylphosphinetriphenylborane. Specific examples of organic phosphine compounds include TPP, TPP-MK, TPP-K, TTBuP-K, TPP-SCN, and TPP-S (all manufactured by Hokko Chemical Industry Co., Ltd.).

[0115] When a curing accelerator is used, its content is preferably 0.001 to 5% by mass, more preferably 0.001 to 2.5% by mass, and even more preferably 0.001 to 1% by mass, based on 100% by mass of the nonvolatile content of the sealing composition, in order to promote the crosslinking reaction between the acid anhydride group and / or carboxyl group of component (A1) and the epoxy group of component (A2).

[0116] (Plasticizer) The sealing composition of the present invention may further contain a plasticizer. Examples of plasticizers include mineral oils such as paraffinic process oils, naphthenic process oils, liquid paraffin, and petrolatum, and vegetable oils such as castor oil, cottonseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, and olive oil.

[0117] <Method for producing a sealing composition> The following describes preferred methods for producing the sealing composition of the present invention. However, the sealing composition of the present invention may also be produced by methods other than those described below.

[0118] A preferred method for producing the sealing composition of the present invention (hereinafter referred to as "the production method of the present invention") includes a step of grinding a mixture containing an olefin polymer having an acid anhydride group and / or a carboxyl group (i.e., component (A1)), calcium oxide with a median diameter greater than 300 nm, and an organic solvent. The sealing composition of the present invention can also be produced by mixing calcium oxide with a median diameter of 300 nm or less (i.e., component (B)) with components other than component (B), but with such a simple mixing, it is difficult to disperse the fine calcium oxide well in the sealing composition compared to the method described above. Furthermore, fine calcium oxide has a large surface area, and as a result, its hygroscopicity is also high. To avoid such hygroscopicity, the handling of fine calcium oxide during the production of the sealing composition is inferior to that of calcium oxide of normal size. Therefore, it is preferable to produce the sealing composition of the present invention through the above-described step. The mixtures used for grinding in the production method of the present invention will be described in order below.

[0119] A mixture for grinding can be produced by mixing calcium oxide with a median diameter exceeding 300 nm, component (A1), and an organic solvent. The calcium oxide content is preferably 3 to 75% by mass, more preferably 5 to 70% by mass, relative to the entire mixture for grinding. The component (A1) content is preferably 3 to 40% by mass, more preferably 5 to 35% by mass, relative to the entire mixture for grinding. The organic solvent content is preferably 20 to 70% by mass, more preferably 30 to 60% by mass, relative to the entire mixture for grinding, in one embodiment of the present invention, or preferably 20 to 60% by mass, more preferably 30 to 50% by mass, in another embodiment of the present invention in which the sealing composition includes component (C). Other components besides those described above (e.g., semi-calcined hydrotalcite (i.e., component (C)), component (A3), tackifiers, etc.) may be added to the mixture for grinding. There are no particular limitations on the order in which the components are added, and each component may be added sequentially or simultaneously.

[0120] Examples of organic solvents that can be used in the manufacturing method of the present invention include acetone and methyl ethyl acetate. Examples of suitable organic solvents include ketones such as ton and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; cellosolves such as cellosolve; carbitols such as butyl carbitol; aromatic hydrocarbons such as toluene and xylene; and amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. Commercially available organic solvents, such as "Swazol" from Maruzen Petrochemical Co., Ltd. and "Ipsol" from Idemitsu Kosan Co., Ltd., may also be used. Only one organic solvent may be used, or two or more may be used in combination.

[0121] The grinding process can be carried out using a known grinder. The grinding process uniformly grinds and disperses the calcium oxide in the mixture. Examples of known grinders include wet bead mills. Examples of bead materials include zirconia, alumina, glass, and steel. The bead diameter is, for example, about 0.03 to 5 mm. The rotational speed of the bead mill's rotating shaft is, for example, about 10 to 10,000 rpm. The flow rate of the mixture for grinding into the grinding chamber of the bead mill is, for example, about 0.1 to 10,000 kg / hour. In wet grinding with a bead mill, it is preferable to cool the mixture with chiller water to suppress the temperature rise during the grinding process. The temperature of the chiller water is, for example, about 0 to 40°C.

[0122] Furthermore, the mixture after pulverization may be mixed with any other component. For example, component (A2), component (A3), a tackifier, etc., may be added to and mixed with the mixture after pulverization. When the sealing composition contains an olefin polymer having epoxy groups, which is component (A2), it is preferable to mix the mixture after pulverization with component (A2) to prevent the crosslinking reaction from proceeding due to the heat during pulverization. That is, the manufacturing method of the present invention preferably further includes a step of mixing the mixture after pulverization with an olefin polymer having epoxy groups (i.e., component (A2)). There are no particular limitations on the order in which each component is added, and each component may be added sequentially or simultaneously.

[0123] If the mixture for grinding contains semi-calcined hydrotalcite (i.e., component (C)), the above grinding process can produce a varnish of the sealing composition of the present invention containing an organic solvent. If the mixture for grinding does not contain component (C), the varnish of the sealing composition of the present invention containing an organic solvent can be produced by mixing the mixture after grinding with component (C).

[0124] The varnish of the sealing composition containing the organic solvent obtained as described above may have some or all of the organic solvent removed by drying or other means. The sealing composition of the present invention may be used in liquid form such as varnish, or in solid form such as film.

[0125] Sealing sheet The present invention also provides a sealing sheet having a laminated structure including a support and a sealing layer formed from the sealing composition of the present invention. A protective sheet may also be used in the present invention. That is, the sealing sheet of the present invention may have a laminated structure including a support, a sealing layer, and a protective sheet in this order. Other layers may be present between the support and the sealing layer, and between the sealing layer and the protective sheet. Examples of other layers include an adhesive layer, a release layer, and a sealing layer formed from a sealing composition that does not contain calcium oxide and / or semi-calcined hydrotalcite.

[0126] The haze of the sealing layer is preferably less than 60%, more preferably 40% or less, and even more preferably 20% or less. There is no particular limit to the lower limit of the haze of the sealing layer, but the haze of the sealing layer is, for example, 0% or more. This haze can be measured in accordance with JIS K 7136. Specifically, this haze is measured using glass as a reference and D65 light. It can be measured by the method described in the Examples section below.

[0127] Examples of support materials and protective sheets include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride; cycloolefin polymers; polyesters such as polyethylene terephthalate (hereinafter sometimes referred to as "PET") and polyethylene naphthalate; polycarbonate; and plastic films such as polyimide. Both the support material and protective sheet may be single-layer films or laminated films.

[0128] As the support and protective sheet, for example, a low-permeability film having a barrier layer, or a laminated film of a low-permeability film having a barrier layer and another film can be used. Examples of the barrier layer include inorganic films such as silica vapor-deposited films, silicon nitride films, and silicon oxide films. The barrier layer may consist of multiple layers of multiple inorganic films (for example, silica vapor-deposited films). The barrier layer may also consist of organic and inorganic materials, or it may be a composite multilayer of an organic layer and an inorganic film.

[0129] The protective sheet is preferably treated with a release agent on the surface that comes into contact with the sealing layer. On the other hand, the support may or may not be treated with a release agent. Examples of release agents include silicone resin-based release agents, alkyd resin-based release agents, and fluororesin-based release agents.

[0130] The thickness of the support and protective sheet is not particularly limited, but from the viewpoint of handling the sealing sheet, they are preferably 10 to 150 μm, more preferably 20 to 100 μm, respectively. If the support and protective sheet are laminated films, the above thickness is the thickness of the laminated film. On the other hand, from the viewpoint of achieving both sealing performance and adhesion, the thickness of the sealing layer is preferably 2 to 100 μm, more preferably 2 to 75 μm, and even more preferably 3 to 50 μm in one embodiment of the present invention, or in another embodiment of the present invention in which the sealing composition contains component (C), it is preferably 3 to 200 μm, more preferably 3 to 150 μm, and even more preferably 3 to 100 μm.

[0131] <Method for manufacturing sealing sheets> The sealing sheet of the present invention can be manufactured, for example, by applying a varnish of the sealing composition obtained as described above to a support to form a coating film, and then drying the resulting coating film to form a sealing layer. Alternatively, a sealing sheet having a laminated structure including a support, a sealing layer, and a protective sheet in this order can be manufactured, for example, by applying and drying varnish to one of the support and the protective sheet to form a sealing layer, and then laminating the other of the support and the protective sheet on top of the formed sealing layer.

[0132] When using component (A2), drying the coating film (i.e., removal of the organic solvent) is preferably carried out by heating the coating film in order to allow the reaction between the epoxy group of component (A2) and the acid anhydride group and / or carboxyl group of component (A1) to proceed. The heating temperature of the coating film is preferably 50 to 200°C, more preferably 80 to 150°C, and the time is preferably 1 to 60 minutes, more preferably 5 to 30 minutes. The heating of the coating film may be carried out under normal pressure or under reduced pressure.

[0133] The coating obtained by removing the organic solvent may be further heated (aged). The heating temperature is preferably 80 to 200°C, more preferably 100 to 150°C, and the duration is preferably 10 to 240 minutes, more preferably 30 to 180 minutes. This heating may be carried out under normal pressure or under reduced pressure.

[0134] Electronic devices The present invention also provides an electronic device comprising a sealing layer formed from the sealing composition of the present invention. Examples of electronic devices include organic EL devices, solar cells, sensor devices, and touch panels having a conductive substrate. Preferably, the electronic device is a moisture-sensitive electronic device such as an organic EL device or a solar cell. [Examples]

[0135] The present invention will be described in more detail below with reference to examples, but the present invention is not limited by the following examples, and it is possible to implement it with appropriate modifications within the scope that is consistent with the spirit of the above and below, and all such modifications are included in the technical scope of the present invention. In addition, unless otherwise specified, "parts" and "%" in the amounts of components and copolymer units mean "parts by mass" and "mass%", respectively.

[0136] <Ingredients> The components used in the examples and comparative examples are shown below. (1)(A1) component "HV-300M" (manufactured by Toho Chemical Industry Co., Ltd., maleic anhydride-modified liquid polybutene, acid anhydride group concentration: 0.77 mmol / g, number average molecular weight: 2,100)

[0137] (2)(A2) component "ER829" (manufactured by Seikoh PMC, glycidyl methacrylate-modified propylene-butene random copolymer, propylene units / butene units: 71% / 29%, epoxy group concentration: 0.64 mmol / g, number average molecular weight: 168,000) "ER866" (manufactured by Seikoh PMC, glycidyl methacrylate-modified butyl rubber, epoxy group concentration: 1.63 mmol / g, number average molecular weight: 113,000, isobutene units / isoprene units: 98.9% / 1.1%)

[0138] (3)(A3) component "HV-1900" (manufactured by ENEOS Corporation, liquid polybutene, number average molecular weight 2,900, viscosity at 25°C: 460 Pa·s)

[0139] (4)(A4) Component "BUTYL065" (manufactured by JSR, butyl rubber, isobutene units / isoprene units: 98.7% / 1.3%)

[0140] (5) Moisture-absorbing filler (5-1) Calcium oxide Calcium oxide (manufactured by Yoshizawa Lime Industry Co., Ltd., median diameter: 2.1 μm) (5-2)(C) component "DHT-4C" (manufactured by Kyowa Chemical Industry Co., Ltd., semi-calcined hydrotalcite, median diameter: 400 nm, BET specific surface area: 15 m²) 2 / g)

[0141] (6) Tackifier "Alcon P-125" (manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point: 125℃)

[0142] (7) Metal complexes "PlenAct Al-M" (manufactured by Ajinomoto Fine Techno Co., Ltd., aluminum octadecenylacetoacetate diisopropylate)

[0143] (8) Antioxidants "Irganox 1010" (BASF, hindered phenol antioxidant)

[0144] (9) Curing accelerator 2,4,6-Tris(dimethylaminomethyl)phenol (manufactured by Nuurion Pharmaceuticals, hereinafter abbreviated as "TAP")

[0145] <Example 1> Varnishes with the formulation ratios shown in Table 1 below were prepared using the following procedure, and sealing sheets were made using the obtained varnishes. The amount (parts) of each component listed in Table 1 below indicates the amount of non-volatile content of each component in the varnish. In Table 1 below, calcium oxide is written as "CaO," and its median diameter is indicated in parentheses. Furthermore, Table 1 below shows the content of hygroscopic filler relative to 100% by mass of the non-volatile content of the sealing composition.

[0146] Specifically, a Swazole solution (non-volatile content: 60%) of a tackifier (Alcon P-125, manufactured by Arakawa Chemical Industries, Ltd.) was mixed with maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industries, Ltd.), liquid polybutene (HV-1900, manufactured by ENEOS Corporation), calcium oxide (manufactured by Yoshizawa Lime Industry Co., Ltd.), and toluene to obtain a mixture for grinding (the total content of the mixture was: organic solvent (i.e., sum of Swazole and toluene): 24%, maleic anhydride-modified liquid polybutene: 10%, calcium oxide: 48%, tackifier: 7%, and liquid polybutene: 11%).

[0147] The mixture for grinding was placed in a wet bead mill (Ashizawa Finetech's Labstar Mini "LMZ015"), and beads (bead diameter: 0.2 mm) were filled to approximately 60% of the effective volume of the grinding chamber. The mixture was then ground to obtain a ground mixture in which calcium oxide was ground and dispersed.

[0148] A small amount was taken from the mixture after grinding, diluted 100-fold with toluene to prepare a sample for measurement, and the median diameter of calcium oxide was measured and calculated using dynamic light scattering with the NANOTRAC WAVE nanoparticle size analyzer manufactured by Microtrac. As a result, the median diameter of calcium oxide was found to be 246 nm.

[0149] To the mixture after grinding, a toluene solution of glycidyl methacrylate-modified propylene-butene random copolymer (ER829, manufactured by Seikoh PMC) (non-volatile content: 15%), a hindered phenol antioxidant (Irganox 1010, manufactured by BASF), and a curing accelerator (TAP, manufactured by Kayaku Nurion Co., Ltd.) were added. The resulting mixture was then mixed in a high-speed rotary mixer to obtain a varnish for sealing.

[0150] A polyethylene terephthalate film (Toyo Cloth Co., Ltd. "SP4020", PET film thickness: 50 μm) with one side treated with a silicone-based release agent and a low-permeability polyethylene terephthalate film (Mitsubishi Chemical Corporation "Tech Barrier HX", PET film thickness: 12 μm) were laminated together so that the side of the SP4020 not treated with the silicone-based release agent was in contact with the Tech Barrier HX to create a laminated film, which was used as a support and protective sheet for a sealing sheet. Hereinafter, the "side of the laminated film treated with the silicone-based release agent" will be referred to as the "release-treated side".

[0151] The obtained varnish was uniformly applied to the release-treated surface of the first laminated film using a die coater and heated at 140°C for 30 minutes. Then, the second laminated film was laminated so that its release-treated surface and the composition layer were in contact, and then heated at 130°C for 60 minutes to obtain a sealing sheet having a sealing layer with a thickness of 10 μm.

[0152] <Example 2> A sealing sheet having a sealing layer with a thickness of 10 μm was prepared using the same method as in Example 1, except that the amount of calcium oxide used was changed from 300 parts to 120 parts.

[0153] <Example 3> A sealing sheet having a 10 μm thick sealing layer was prepared in the same manner as in Example 1, except that the bead diameter of the wet bead mill was changed from 0.2 mm to 0.1 mm. The median diameter of calcium oxide in the mixture after the grinding treatment in Example 3 was measured in the same manner as in Example 1, and the median diameter was found to be 185 nm.

[0154] <Example 4> A sealing sheet was prepared in the same manner as in Example 1, except that the thickness of the sealing layer was changed from 10 μm to 5 μm.

[0155] <Example 5> The sealing sheet was prepared in the same manner as in Example 2, except that the thickness of the sealing layer was changed from 10 μm to 20 μm.

[0156] <Example 6> A sealing sheet having a sealing layer with a thickness of 10 μm was prepared in the same manner as in Example 3, except that the toluene solution (non-volatile content: 15%) of glycidyl methacrylate-modified propylene-butene random copolymer (Seiko PMC's "ER829") was replaced with a toluene solution (non-volatile content: 25%) of glycidyl methacrylate-modified butyl rubber (Seiko PMC's "ER866").

[0157] <Example 7> A sealing sheet having a sealing layer with a thickness of 10 μm was prepared using the same method as in Example 3, except that the toluene solution (non-volatile content: 15%) of glycidyl methacrylate-modified propylene-butene random copolymer (Seiko PMC's "ER829") was replaced with a toluene solution (non-volatile content: 15%) of butyl rubber (JSR's "BUTYL065").

[0158] <Comparative Example 1> A swazole solution (non-volatile content: 60%) of a tackifier (Alcon P-125, manufactured by Arakawa Chemical Industries, Ltd.) was mixed with maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industries, Ltd.), liquid polybutene (HV-1900, manufactured by ENEOS Corporation), and semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) using a three-roll mixer to obtain a mixture. To the obtained mixture, a swazole solution (non-volatile content: 15%) of glycidyl methacrylate-modified propylene-butene random copolymer (ER829, manufactured by Seikoh PMC, Ltd.), a hindered phenol antioxidant (Irganox 1010, manufactured by BASF), a curing accelerator (TAP, manufactured by Kayaku Nurion Co., Ltd.), and toluene were added and mixed using a high-speed rotary mixer to obtain a varnish for sealing composition. A sealing sheet having a sealing layer with a thickness of 10 μm was prepared from the obtained varnish using the same method as in Example 1.

[0159] <Comparative Example 2> A sealing sheet having a 10 μm thick sealing layer was prepared using the same method as in Comparative Example 1, except that the semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) was replaced with calcium oxide (manufactured by Yoshizawa Lime Industry Co., Ltd., median diameter: 2.1 μm).

[0160] <Comparative Example 3> A mixture for grinding was prepared in the same manner as in Example 1, except that maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industry Co., Ltd.) was not used (the entire mixture The content of organic solvents (i.e., the combined content of swarzol and toluene) relative to the body is 26%, calcium oxide content is 53%, tackifier content is 8%, and liquid polybutene content is 12%.

[0161] We attempted to grind and disperse calcium oxide by placing the mixture for grinding into a wet bead mill (Ashizawa Finetech's Labstar Mini "LMZ015", bead diameter: 0.2 mm). However, due to a significant increase in the viscosity of the mixture for grinding, we were unable to produce a varnish for the sealing composition in which calcium oxide with a median diameter of 300 nm or less was dispersed.

[0162] <Example 8> Varnishes with the formulation ratios shown in Table 2 below were prepared using the following procedure, and sealing sheets were made using the obtained varnishes. The amount (parts) of each component listed in Table 2 below indicates the amount of non-volatile content of each component in the varnish. In Table 2 below, "calcium oxide" is written as "CaO", "calcium oxide with a median diameter exceeding 300 nm" is written as "(B') component", and the median diameter of the calcium oxide used is also indicated. Furthermore, Table 2 below shows the calcium oxide content and the semi-calcined hydrotalcite content relative to 100% by mass of the non-volatile content of the sealing composition.

[0163] Specifically, the tackifier (Alcon P-125 manufactured by Arakawa Chemical Industries, Ltd.) is Swazole. A solution (non-volatile content: 60%) was mixed with maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industry Co., Ltd.), liquid polybutene (HV-1900, manufactured by ENEOS Corporation), calcium oxide (manufactured by Yoshizawa Lime Industry Co., Ltd.), and toluene to obtain a mixture for grinding (the total content of the mixture was: organic solvent (i.e., sum of Swarzol and toluene): 35%, maleic anhydride-modified liquid polybutene: 7%, calcium oxide: 23%, tackifier: 16%, and liquid polybutene: 19%).

[0164] The mixture for grinding was placed in a wet bead mill (Ashizawa Finetech's Labstar Mini "LMZ015"), and beads (bead diameter: 0.1 mm) were filled to approximately 60% of the effective volume of the grinding chamber. The mixture was then ground to obtain a ground mixture in which calcium oxide was ground and dispersed.

[0165] A small amount was taken from the mixture after grinding, diluted 100-fold with toluene to prepare a sample for measurement, and the median diameter of calcium oxide was measured and calculated using dynamic light scattering with the NANOTRAC WAVE nanoparticle size analyzer manufactured by Microtrac. As a result, the median diameter of calcium oxide was found to be 185 nm.

[0166] The mixture after pulverization was mixed with a toluene solution (non-volatile content: 15%) of semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.), glycidyl methacrylate-modified propylene-butene random copolymer (ER829, manufactured by Seikoh PMC Co., Ltd.), a metal complex (Plenact Al-M, manufactured by Ajinomoto Fine Techno Co., Ltd.), a hindered phenol antioxidant (Irganox 1010, manufactured by BASF), and a curing accelerator (TAP, manufactured by Kayaku Nurion Co., Ltd.). The resulting mixture was mixed in a high-speed rotary mixer to obtain a varnish for sealing.

[0167] A polyethylene terephthalate film (Toyo Cloth Co., Ltd. "SP4020", PET film thickness: 50 μm) with one side treated with a silicone-based release agent and a low-permeability polyethylene terephthalate film (Mitsubishi Chemical Corporation "Tech Barrier HX", PET film thickness: 12 μm) were laminated together so that the side of the SP4020 not treated with the silicone-based release agent was in contact with the Tech Barrier HX to create a laminated film, which was used as a support and protective sheet for a sealing sheet. Hereinafter, the "side of the laminated film treated with the silicone-based release agent" will be referred to as the "release-treated side".

[0168] The obtained varnish was uniformly applied to the release-treated surface of the first laminated film using a die coater and heated at 140°C for 30 minutes. Then, the second laminated film was laminated so that its release-treated surface and the composition layer were in contact, and then heated at 130°C for 60 minutes to obtain a sealing sheet having a sealing layer with a thickness of 50 μm.

[0169] <Example 9> A sealing sheet having a sealing layer with a thickness of 50 μm was prepared in the same manner as in Example 8, except that the amount of component (B) used was changed from 96 parts to 60 parts, and the amount of component (C) used was changed from 144 parts to 180 parts.

[0170] <Example 10> A sealing sheet was prepared in the same manner as in Example 8, except that the thickness of the sealing layer was changed from 50 μm to 20 μm.

[0171] <Example 11> A sealing sheet having a 20 μm thick sealing layer was prepared using the same method as in Example 8, except that the bead diameter of the wet bead mill was changed from 0.1 mm to 0.2 mm. The median diameter of the calcium oxide in the mixture after grinding in Example 11 was measured in the same manner as in Example 8, and the median diameter was found to be 246 nm.

[0172] <Example 12> A sealing sheet having a sealing layer with a thickness of 50 μm was prepared in the same manner as in Example 8, except that the toluene solution (non-volatile content: 15%) of glycidyl methacrylate-modified propylene-butene random copolymer (Seiko PMC's "ER829") was replaced with a toluene solution (non-volatile content: 25%) of glycidyl methacrylate-modified butyl rubber (Seiko PMC's "ER866").

[0173] <Example 13> A sealing sheet having a sealing layer with a thickness of 50 μm was prepared using the same method as in Example 8, except that the toluene solution (non-volatile content: 15%) of glycidyl methacrylate-modified propylene-butene random copolymer (Seiko PMC's "ER829") was replaced with a toluene solution (non-volatile content: 15%) of butyl rubber (JSR's "BUTYL065").

[0174] <Comparative Example 4> A swazole solution (non-volatile content: 60%) of a tackifier (Alcon P-125, manufactured by Arakawa Chemical Industries, Ltd.) was mixed with maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industries, Ltd.), liquid polybutene (HV-1900, manufactured by ENEOS Corporation), and semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) using a three-roll mixer to obtain a mixture. To the obtained mixture, a swazole solution (non-volatile content: 15%) of glycidyl methacrylate-modified propylene-butene random copolymer (ER829, manufactured by Seikoh PMC, Ltd.), a hindered phenol antioxidant (Irganox 1010, manufactured by BASF), a curing accelerator (TAP, manufactured by Kayaku Nurion Co., Ltd.), and toluene were added and mixed using a high-speed rotary mixer to obtain a varnish for sealing composition. A sealing sheet having a sealing layer with a thickness of 50 μm was prepared from the obtained varnish using the same method as in Example 8.

[0175] <Comparative Example 5> A sealing sheet having a sealing layer with a thickness of 50 μm was prepared in the same manner as in Comparative Example 4, except that the amount of component (C) used was changed from 240 parts to 180 parts, and 60 parts of calcium oxide (median diameter: 2.1 μm) were also used.

[0176] <Comparative Example 6> A mixture for grinding was prepared in the same manner as in Example 8, except that maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industry Co., Ltd.) was not used (the total content of the mixture was: organic solvent (i.e., sum of swarol and toluene): 38%, calcium oxide: 24%, tackifier: 17%, and liquid polybutene: 20%).

[0177] We attempted to grind and disperse calcium oxide by placing the mixture for grinding into a wet bead mill (Ashizawa Finetech's Labstar Mini "LMZ015", bead diameter: 0.1 mm). However, due to a significant increase in the viscosity of the mixture for grinding, we were unable to produce a varnish for the sealing composition in which calcium oxide with a median diameter of 300 nm or less was dispersed.

[0178] The transparency and water vapor barrier properties of the sealing layers of the sealing sheets obtained in the examples and comparative examples were evaluated by the following methods.

[0179] <Method for evaluating transparency> The sealing sheets prepared in the examples and comparative examples were cut to a length of 70 mm and a width of 25 mm. The protective sheet was peeled off the cut sealing sheets, and the sealing sheets having a laminated structure of sealing layer / support were laminated onto a glass plate (Matsunami Glass Industry Co., Ltd. "White Slide Glass S1112 Edge Polished No. 2", length: 76 mm, width: 26 mm, and thickness: 1.2 mm) using a batch-type vacuum laminator (Nichigo Morton Co., Ltd., V-160) to obtain evaluation samples having a laminated structure of glass / sealing layer / support. The lamination conditions were a temperature of 80°C, a depressurization time of 30 seconds, followed by pressurization at a pressure of 0.3 MPa for 30 seconds.

[0180] Haze (%) was measured in accordance with JIS K 7136. Specifically, after peeling off the support of an evaluation sample having a laminated structure of glass / sealing layer / support, the haze (%) of the evaluation sample with the support peeled off was measured using a Suga Test Instruments HZ-V3 haze meter (halogen lamp) with glass as a reference and D65 light, and transparency was evaluated according to the following criteria. The results are shown in the table below. (Transparency standards) ○ (Good): Haze is less than 30% △ (Acceptable): Haze is 30% or more, but less than 60%. × (Defective): Haze is 60% or more

[0181] <Method for evaluating water vapor barrier properties> As a support, a composite film comprising aluminum foil and polyethylene terephthalate film (Tokai Toyo Aluminum Sales Co., Ltd.'s "PET-Tsuki AL1N30" (aluminum foil thickness: 30 μm, PET film thickness: 25 μm)) was prepared.

[0182] A test sheet having a laminated structure of "support (composite film) / sealing layer / protective sheet (laminated film)" was obtained in the same manner as in the examples and comparative examples, except that the aforementioned composite film was used as the support.

[0183] A 50mm x 50mm square glass plate made of alkali-free glass was prepared. This glass plate was washed with boiled isopropyl alcohol for 5 minutes and dried at 150°C for 30 minutes or more.

[0184] Calcium was deposited on one side of the dried glass plate using a mask that covered the peripheral area at a distance of 0 mm to 2 mm from the edge of the glass plate. As a result, the aforementioned A 200 nm thick calcium film (99.8% purity) was formed in the central portion of the glass plate, excluding the peripheral area 0 mm to 2 mm from the edges.

[0185] In a nitrogen atmosphere, the sealing layer of the test sheet described above and the calcium film side of the glass plate were bonded together using a thermal laminator (Fujiplas Corporation's "Lamipacker DAiSY A4 (LPD2325)") to obtain a laminate. This laminate was used as an evaluation sample.

[0186] Generally, when calcium comes into contact with water, it becomes transparent as calcium oxide. Furthermore, in the evaluation sample described above, the glass plate and aluminum foil have sufficiently high water vapor intrusion barrier properties, so moisture usually moves in the in-plane direction (perpendicular to the thickness direction) through the edges of the sealing layer and reaches the calcium film. When moisture penetrates the evaluation sample, the calcium film is gradually oxidized from the edges and becomes transparent, so a shrinkage of the calcium film is observed. Therefore, moisture penetration into the evaluation sample can be evaluated by measuring the sealing distance (mm) from the edge of the evaluation sample to the calcium film. Thus, the evaluation sample containing the calcium film can be used as a model for electronic devices.

[0187] First, the sealing distance X2 (mm) from the edge of the evaluation sample to the edge of the calcium film was measured using a microscope (Mitutoyo "Measuring Microscope MF-U").

[0188] Next, the evaluation sample was placed in a constant temperature and humidity chamber set to 85°C and 85% RH. The evaluation sample was removed from the chamber when the sealing distance X1 (mm) between the edge of the evaluation sample and the edge of the calcium film increased by 0.1 mm compared to the initial sealing distance X2. The time from when the evaluation sample was placed in the chamber to when it was removed was defined as the decrease start time t [hours]. This decrease start time t is calculated from the time T when the evaluation sample was placed in the chamber. P1 Therefore, at the point T in which the sealing distance X1 [mm] between the end of the evaluation sample stored in the constant temperature and humidity chamber and the end of the calcium membrane becomes "X2 + 0.1 mm", P2 This corresponds to the time until [a certain point].

[0189] The sealing distance X1 and the decrease start time t were applied to Fick's diffusion equation in equation (1) to calculate the constant K as a water vapor intrusion barrier parameter.

[0190]

number

[0191] The water vapor intrusion barrier properties of the sealing layer were evaluated using the obtained constant K according to the following criteria. A smaller value of constant K indicates higher water vapor intrusion barrier properties. Note that "hr" below refers to "time". The results are shown in the table below. Note that "(cm / hr^0.5)" in the table below refers to "(cm / hr 0.5 It means ")". (Standards for water vapor barrier properties) ○ (Good): Constant K is 0.025 cm / h 0.5 less than × (Defective): Constant K is 0.025 cm / hr 0.5 That's all.

[0192] [Table 1]

[0193] The sealing layers formed from the sealing compositions of Examples 1 to 7, which satisfy the requirements of the present invention, exhibited superior water vapor intrusion barrier properties compared to the sealing layer formed from the sealing composition of Comparative Example 1, which used semi-calcined hydrotalcite instead of calcium oxide. Furthermore, the sealing layers formed from the sealing compositions of Examples 1 to 7 exhibited lower haze and superior transparency compared to the sealing layer formed from the sealing composition of Comparative Example 2, which used calcium oxide with a median diameter exceeding 300 nm.

[0194] [Table 2]

[0195] The sealing layers formed from the sealing compositions of Examples 8 to 13, which satisfy the requirements of the present invention, exhibited superior water vapor intrusion barrier properties compared to the sealing layer formed from the sealing composition of Comparative Example 4, which does not use component (B). Furthermore, the sealing layers formed from the sealing compositions of Examples 8 to 13 exhibited lower haze and superior transparency compared to the sealing layer formed from the sealing composition of Comparative Example 5, which used calcium oxide with a median diameter exceeding 300 nm (component (B')) instead of component (B). [Industrial applicability]

[0196] The sealing composition and sealing sheet of the present invention are useful, for example, for sealing electronic devices (e.g., organic EL devices, solar cells, sensor devices, touch panels having conductive substrates, etc.).

Claims

1. The following components (A) and (B): (A) Olefin polymers, and (B) Calcium oxide A sealing composition comprising, (A) Component comprises (A1) an olefin polymer having an acid anhydride group and / or a carboxyl group, and (A4) a non-liquid olefin polymer that does not have any acid anhydride group, carboxyl group, or epoxy group. (A1) The content of component is 5% by mass or more and 35% by mass or less, relative to 100% by mass of the nonvolatile content of the sealing composition. (B) The content of component is 20% by mass or more and 70% by mass or less, relative to 100% by mass of the nonvolatile content of the sealing composition, and (B) A sealing composition in which the median diameter of component is 300 nm or less.

2. The following (C) components: (C) Semi-calcined hydrotalcite The sealing composition according to claim 1, further comprising:

3. The encapsulating composition according to claim 1 or 2, wherein the median diameter of component (B) is 1 nm or more.

4. The sealing composition according to claim 1 or 2, wherein component (A4) is a propylene-butene copolymer or an isobutene-isoprene copolymer.

5. The sealing composition according to claim 1 or 2, wherein the content of component (A4) is 25% by mass or less based on 100% by mass of the nonvolatile content of the sealing composition.

6. The sealing composition according to claim 2, wherein the content of component (C) is 20 to 70% by mass relative to 100% by mass of the nonvolatile content of the sealing composition.

7. (A1) The encapsulation composition according to claim 1 or 2, wherein the olefin polymer having an acid anhydride group and / or a carboxyl group is an olefin polymer having an acid anhydride group.

8. The encapsulation composition according to claim 1 or 2, wherein component (A) comprises an olefin polymer having an epoxy group (A2).

9. The encapsulating composition according to claim 1 or 2, wherein component (A) comprises (A3) a liquid olefin polymer.

10. The sealing composition according to claim 1 or 2, further comprising a tackifier.

11. A sealing sheet having a laminated structure comprising a support and a sealing layer formed from the sealing composition according to claim 1 or 2.

12. The sealing sheet according to claim 11, wherein the haze of the sealing layer is less than 60%.

13. An electronic device comprising a sealing layer formed from the sealing composition according to claim 1 or 2.

14. (A1) A method for producing a sealing composition according to claim 1 or 2, comprising the step of grinding a mixture containing an olefin polymer having an acid anhydride group and / or a carboxyl group, calcium oxide having a median diameter of 300 nm or more, and an organic solvent.

15. The manufacturing method according to claim 14, further comprising the step of mixing the mixture after pulverization with an olefin polymer having an epoxy group (A2).

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