Composition for sealing electronic devices, method for forming sealing film for electronic devices, and sealing film for electronic devices

Abstract

A composition for electronic device sealing according to the present invention contains a photocurable monomer and a photopolymerization initiator; the photocurable monomer contains a photocurable monomer (A) that does not have an aromatic hydrocarbon group and a photocurable monomer (B) that has an aromatic hydrocarbon group; the photocurable monomer (B) contains a hydrocarbon group which contains two or more substituted or unsubstituted phenyl groups having a specific structure, or a heteroatom-containing hydrocarbon group which contains two or more substituted or unsubstituted phenyl groups; the photocurable monomer (B) contains at least a mono(meth)acrylate or a di(meth)acrylate; and a metal-containing compound (C) that is selected from among a metal alkoxide compound, a metal chelate compound, a silane compound, a silazane compound and a metal halide compound is additionally contained therein.

Description

[Technical Field]

[0001] The present invention relates to a composition for sealing an electronic device, a method for forming an electronic device sealing film, and an electronic device sealing film, and in particular to a composition for sealing an electronic device that prevents moisture penetration, has excellent sealing performance and flex resistance, and can improve luminous efficiency. [Background technology]

[0002] In electronic devices, particularly organic electroluminescence devices (hereinafter also referred to as "organic EL devices" or "organic EL elements"), it has been proposed to cover the surface of the organic EL element with a sealing layer in order to prevent the organic materials and electrodes used therein from being deteriorated by moisture.

[0003] As a technique for sealing an organic EL element, for example, Patent Document 1 discloses a display device in which an organic protective film is formed on the surface of an organic EL element by a method such as vapor deposition or inkjet printing using a composition containing a monomer having no aromatic hydrocarbon group and a monomer having an aromatic hydrocarbon group, the monomer having an aromatic hydrocarbon group containing two or more phenyl groups and heteroatoms, and a mono(meth)acrylate and a di(meth)acrylate. However, in the display device described in Patent Document 1, the diffusion coefficient of the organic protective film is sufficiently low, so moisture permeation is a problem under harsh conditions of high temperature and high humidity, such as 85°C, 85% RH, and 100 hours or more. Furthermore, there are problems with the stress difference between the organic protective film and adjacent layers, insufficient adhesive strength, and bending resistance when bent.

[0004] On the other hand, as a technology for sealing an organic EL element, for example, the technology described in Patent Document 2 discloses an organic EL device having a first protective film formed by a dry method (CVD method) on the surface of the organic EL element so as to cover the organic EL element, and a second protective film formed by a wet method on the surface of the first protective film and for filling in the unattached portions of the first protective film. However, in the organic EL device described in Patent Document 2, the second protective film is denatured in a high-temperature, high-humidity environment, and the high stress of the second protective film causes a problem of moisture penetration at the interface between the first and second protective films (presumably due to deterioration of interfacial adhesion between the first and second protective films) under high-temperature, high-humidity conditions of 85°C and 85% RH for 100 hours or more, resulting in poor sealing performance. Furthermore, when sealing is performed in this manner, there is a problem of deterioration in the luminous efficiency of the organic EL element. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2018-504735 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-56587 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above problems and circumstances, and an object of the present invention is to provide a composition for sealing an electronic device, a method for forming an electronic device sealing film, and an electronic device sealing film that can prevent moisture penetration, have excellent sealing performance and flex resistance, and further improve luminous efficiency. [Means for solving the problem]

[0007] In the course of investigating the causes of the above problems in order to solve the above problems, the present inventors discovered that a composition for sealing electronic devices, etc., which has excellent sealing performance, flex resistance, and luminous efficiency, can be provided by containing a photocurable monomer (A) which does not have an aromatic hydrocarbon group and a photocurable monomer (B) which has an aromatic hydrocarbon group, where the photocurable monomer (B) has a specific structure, and further containing a metal-containing compound (C) selected from a metal alkoxide compound, a metal chelate compound, a silane-based compound, a silazane-based compound, and a metal halide-based compound, and thus arrived at the present invention. That is, the above-mentioned problems of the present invention are solved by the following means.

[0008] 1. A composition for sealing electronic devices, comprising a photocurable monomer and a photopolymerization initiator, the photocurable monomer contains a photocurable monomer (A) having no aromatic hydrocarbon group and a photocurable monomer (B) having an aromatic hydrocarbon group, The photocurable monomer (B) contains a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, and has a structure represented by the following general formula (1): the photocurable monomer (B) contains at least a mono(meth)acrylate or a di(meth)acrylate, Furthermore, metal alkoxide compounds, metal chelate compounds , and and a metal-containing compound (C) selected from metal halide compounds, The metal M constituting the metal-containing compound (C) is at least one of Ti, Al, and Zr. A composition for sealing electronic devices. [ka] [In the general formula (1), P represents a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups. Z 1 and Z 2each independently has a structure represented by the following general formula (2), where a and b are each an integer of 0 to 2, and a+b is an integer of 1 to 4. [ka] [In the general formula (2), * represents a linking point to the carbon of P. X represents a single bond, O, or S. Y represents a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. R 1 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and c is an integer of 0 or 1.]

[0009] 2. The composition for sealing an electronic device according to item 1, wherein the content of the metal-containing compound (C) in the entire composition for sealing an electronic device is within the range of 0.1 to 15 mass %.

[0011] 3 Item 1, wherein the photocurable monomer (A) is at least one of a mono(meth)acrylate having an amine group, a di(meth)acrylate having a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a di(meth)acrylate having an ethylene oxide group, a tri(meth)acrylate having an ethylene oxide group, and a mono(meth)acrylate and di(meth)acrylate having a cyclic carbonized alkyl group. or paragraph 2 The composition for sealing an electronic device according to claim 1.

[0012] 4The photocurable monomer (B) is 4-(meth)acryloxy-2-hydroxybenzophenone, ethyl-3,3-diphenyl(meth)acrylate, benzoyloxyphenyl(meth)acrylate, bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 2-phenylphenoxyethyl(meth)acrylate, 2,2'-phenylphenoxyethyl di(meth)acrylate, 2-phenylphenoxypropyl(meth)acrylate, 2,2'-phenylphenoxypropyl di(meth)acrylate, 2-phenylphenoxybutyl(meth)acrylate, 2,2'-phenylphenoxybutyl di(meth)acrylate, 2-(3-phenylphenyl)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate, 2-phenyl-2-(phenylthio)ethyl(meth)acrylate, 2-(triphenyl ... (4-benzylphenyl)ethyl (meth)acrylate, 4,4'-di(acryloyloxymethyl)biphenyl, 2,2'-di(2-acryloyloxyethoxy)biphenyl, structural isomers thereof, or mixtures thereof. 3 Item 1. The composition for sealing an electronic device according to any one of items 1 to 5.

[0013] 5 .Items 1 to 5 4 A method for forming a sealing film using the composition for sealing an electronic device according to any one of claims 1 to 5, comprising: forming a first encapsulation layer on the electronic device by a vapor deposition process; and forming a second sealing layer by applying the electronic device sealing composition onto the first sealing layer.

[0014] 6 The method further includes a step of forming a third sealing layer on the second sealing layer by a vapor phase method. 5 Item 1. The method for forming an electronic device sealing film according to item 1.

[0015] 7 The step of forming the second sealing layer is a step of forming a second sealing layer using an inkjet method. 5 Section or Article 6 Item 1. The method for forming an electronic device sealing film according to item 1.

[0016] 8 An electronic device sealing film for sealing an electronic device, a first encapsulation layer comprising silicon nitride, silicon oxide, or silicon oxynitride; No. 1 Section to section 4 and a second sealing layer formed using the composition for sealing an electronic device according to any one of items 1 to 5.

[0017] 9 The second sealing layer contains a polymer having a structure represented by the following general formula (3A) and the following general formula (3B) and the metal-containing compound (C). 8 Item 1. The electronic device sealing film according to item 1. [ka] [In the general formula (3A) and the general formula (3B), R1 represents a hydrogen atom or a methyl group. A has a structure that does not have an aromatic hydrocarbon group. B has an aromatic hydrocarbon group, and includes a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, having a structure represented by the general formula (1), and includes at least a mono(meth)acrylate or a di(meth)acrylate.]

[0018] 10A third sealing layer containing silicon nitride, silicon oxide, or silicon oxynitride is provided on the second sealing layer. 8 Section or Article 9 Item 1. The electronic device sealing film according to item 1.

[0019] 11 The content of the metal-containing compound (C) in the second sealing layer is within a range of 0.1 to 15 mass %. 8 Section to section 10 Item 1. The electronic device sealing film according to any one of items 1 to 5. [Effects of the Invention]

[0020] The above-described means of the present invention can provide a composition for sealing an electronic device, a method for forming an electronic device sealing film, and an electronic device sealing film that can prevent moisture penetration, have excellent sealing performance and flex resistance, and further improve luminous efficiency. The mechanism by which the effects of the present invention are manifested or the mechanism of action is not clear, but is speculated as follows.

[0021] (moisture permeation) The electronic device encapsulation composition of the present invention contains the photocurable monomer (A) without an aromatic hydrocarbon group, the photocurable monomer (B) with an aromatic hydrocarbon group, and the metal-containing compound (C). The ligands of the metal-containing compound (C) form a network in the acrylic resin, which is a polymer composed of the photocurable monomer (A) without an aromatic hydrocarbon group and the photocurable monomer (B) with an aromatic hydrocarbon group. This inhibits micro- and macro-Brownian motion of the acrylic resin polymer chains, and the oxycarbonyl groups in the polymer interact with water, thereby preventing water diffusion. Furthermore, the metal and ligands of the metal-containing compound (C) interact or react with water, thereby inhibiting water migration, thereby also preventing water diffusion. As a result, moisture permeation is inhibited, resulting in excellent encapsulation performance.

[0022] (Luminous efficiency of electronic devices) The second sealing layer contains not only a polymer of an organic compound, but also the metal-containing compound (C) and compounds derived therefrom, which have a relatively similar chemical structure to the compounds constituting the first sealing layer and the third sealing layer. This reduces the gradient caused by the difference in refractive index between the adjacent first sealing layer / second sealing layer / third sealing layer, and suppresses light reflection between the layers, thereby improving the light extraction efficiency, i.e., improving the light-emitting efficiency of the electronic device.

[0023] (bending resistance) The metal or ligand contained in the metal-containing compound (C) contained in the second sealing layer interacts or has affinity with the compound constituting the adjacent layer, for example, to strengthen the interaction with the adjacent first sealing layer or third sealing layer, improving adhesion, which in turn improves resistance to interlayer stress generated by bending and provides excellent flex resistance. Furthermore, since the metal-containing compound (C) prevents water diffusion, reliability can be ensured even with a thin film. A thin film reduces stress when bent, reducing delamination. DETAILED DESCRIPTION OF THE INVENTION

[0024] The composition for encapsulating electronic devices of the present invention is a composition for encapsulating electronic devices containing a photocurable monomer and a photopolymerization initiator, wherein the photocurable monomer contains a photocurable monomer (A) that does not have an aromatic hydrocarbon group and a photocurable monomer (B) that has an aromatic hydrocarbon group, and the photocurable monomer (B) contains a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, and has a structure represented by the following general formula (1): This feature is a technical feature common to or corresponding to each of the following embodiments.

[0025] In an embodiment of the present invention, it is preferable that the content of the metal-containing compound (C) in the entire composition for electronic device encapsulation is within a range of 0.1 to 15 mass %, from the viewpoints of photocurability of the composition for electronic device encapsulation and improvement of the luminous efficiency of the electronic device.

[0026] Furthermore, it is preferable that the metal M constituting the metal-containing compound (C) is at least one of Ti, Si, Al and Zr, in terms of inhibiting water movement and inhibiting moisture permeation.

[0027] Furthermore, in terms of improving the reliability of electronic devices and inkjet ejection suitability, it is preferable that the photocurable monomer (A) is at least one of a mono(meth)acrylate having an amine group, a di(meth)acrylate having a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a di(meth)acrylate having an ethylene oxide group, a tri(meth)acrylate having an ethylene oxide group, or a mono(meth)acrylate or di(meth)acrylate having a cyclic carbonized alkyl group.

[0028] Furthermore, the photocurable monomer (B) may be 4-(meth)acryloxy-2-hydroxybenzophenone, ethyl-3,3-diphenyl(meth)acrylate, benzoyloxyphenyl(meth)acrylate, bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 2-phenylphenoxyethyl(meth)acrylate, 2,2'-phenylphenoxyethyl di(meth)acrylate, 2-phenylphenoxypropyl(meth)acrylate, 2,2'-phenylphenoxypropyl di(meth)acrylate, 2-phenylphenoxybutyl(meth)acrylate, 2,2'-phenylphenoxybutyl di(meth)acrylate, 2-(3-phenylphenyl)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate, 2-phenyl-2-(phenylthio)ethyl(meth)acrylate, 2-(triphenylmethyloxy)ethyl (

[0039] In terms of improving the reliability of electronic devices and inkjet ejection suitability, the acrylic acid ester is preferably any one of 4-(triphenylmethyloxy)butyl(meth)acrylate, 3-(biphenyl-2-yloxy)butyl(meth)acrylate, 2-(biphenyl-2-yloxy)butyl(meth)acrylate, 4-(biphenyl-2-yloxy)propyl(meth)acrylate, 3-(biphenyl-2-yloxy)propyl(meth)acrylate, 2-(biphenyl-2-yloxy)propyl(meth)acrylate, 4-(biphenyl-2-yloxy)ethyl(meth)acrylate, 3-(biphenyl-2-yloxy)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate, 4,4'-di(acryloyloxymethyl)biphenyl, 2,2'-di(2-acryloyloxyethoxy)biphenyl, structural isomers thereof, or mixtures thereof.

[0029] The method for forming an electronic device sealing film of the present invention is a method for forming a sealing film using the electronic device sealing composition, and includes the steps of forming a first sealing layer on an electronic device by a vapor phase method and forming a second sealing layer by applying the electronic device sealing composition on the first sealing layer, thereby providing a method for forming an electronic device sealing film that prevents moisture penetration, has excellent sealing performance, excellent flex resistance, and can further improve luminous efficiency.

[0030] Furthermore, it is preferable to include a step of forming a third sealing layer on the second sealing layer by a vapor phase method, in terms of achieving better sealing performance.

[0031] Furthermore, it is preferable that the step of forming the second sealing layer uses an inkjet method, since this allows for highly accurate layer formation.

[0032] The electronic device sealing film of the present invention is an electronic device sealing film for sealing an electronic device, and includes a first sealing layer containing silicon nitride, silicon oxide, or silicon oxynitride, and a second sealing layer using the electronic device sealing composition described in any one of items 1 to 5. This makes it possible to provide an electronic device sealing film that prevents moisture penetration, has excellent sealing performance, excellent flex resistance, and can further improve luminous efficiency.

[0033] The present invention, its components, and embodiments and modes for carrying out the present invention will be described below. In this application, the symbol "to" is used to mean that the numerical values ​​before and after it are included as lower and upper limits.

[0034] In this specification, "(meth)acrylic" means acrylic and / or methacrylic. Furthermore, unless otherwise defined, the term "substituted" means that one or more hydrogen atoms in the functional group of the present invention are substituted with a hydroxy group, a nitro group, an imino group (=NH, =NR, where R is an alkyl group having 1 to 10 carbon atoms), an amidino group, a hydrazine or hydrazone group, a carboxy group, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 3 to 30 carbon atoms, or a heterocycloalkyl group having 2 to 30 carbon atoms. Furthermore, the term "heteroatom" refers to any one atom selected from the group consisting of N, O, S, and P, and "hetero" refers to a carbon atom substituted with any one atom selected from the group consisting of N, O, S, and P. The term "alkylene group" refers to an alkanediyl group connected by a saturated hydrocarbon group without a double bond between the (meth)acrylates at both ends. The number of carbon atoms in the alkylene group refers to only the number of carbon atoms in the alkylene group itself, excluding the carbon atoms in the di(meth)acrylate group.

[0035] In addition, the term "electronic device" as used herein refers to an element that generates, amplifies, converts, or controls an electrical signal by utilizing the kinetic energy, potential energy, etc., of electrons. Examples of such elements include active elements such as light-emitting diode elements, organic electroluminescence elements, photoelectric conversion elements, and transistors. In addition, in the present invention, passive elements that perform passive tasks such as "resisting" or "storing" external influences, such as resistors and capacitors, are also included in the term electronic devices. Therefore, the sealing composition of the present invention is used to form a sealing film for sealing the above-mentioned electronic device.

[0036] [Electronic device encapsulation composition] The composition for encapsulating electronic devices of the present invention (hereinafter also simply referred to as "encapsulating composition") is a composition for encapsulating electronic devices containing a photocurable monomer and a photopolymerization initiator, wherein the photocurable monomer contains a photocurable monomer (A) that does not have an aromatic hydrocarbon group and a photocurable monomer (B) that has an aromatic hydrocarbon group, and the photocurable monomer (B) contains a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, and has a structure represented by the following general formula (1):

[0037] The photocurable monomer refers to a photocurable monomer that can undergo a curing reaction in the presence of a photopolymerization initiator. The photocurable monomer may be a non-silicon monomer that does not contain silicon (Si), such as, but not limited to, a monomer consisting of only an element selected from C, H, O, N, and S. The photocurable monomer may be synthesized by a conventional synthesis method or may be purchased as a commercially available product. The photocurable monomer contains the photocurable monomer (A) having no aromatic hydrocarbon group and the photocurable monomer (B) having an aromatic hydrocarbon group.

[0038] <Photocurable Monomer (A) Having No Aromatic Hydrocarbon Group> The photocurable monomer (A) having no aromatic hydrocarbon group (hereinafter also simply referred to as "photocurable monomer (A)") may include a monomer having no aromatic hydrocarbon group and having 1 to 20, specifically 1 to 6, of one or more vinyl groups, acrylic groups, and methacrylic groups as photocurable functional groups, for example, 1 to 3, 1 to 2, 1, or 2 groups.

[0039] In the present invention, the weight average molecular weight of the photocurable monomer (A) may be in the range of 100 to 500 g / mol, 130 to 400 g / mol, or 200 to 300 g / mol. By setting the weight average molecular weight of the monomer within this range, more advantageous effects can be achieved in terms of processing.

[0040] The photocurable monomer (A) may include a monofunctional monomer having a photocurable functional group, a polyfunctional monomer, or a mixture thereof.

[0041] Specifically, the photocurable monomer (A) may be a (meth)acrylate monomer, or may be an unsaturated carboxylic acid ester having an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or an unsaturated carboxylic acid ester having a hydroxy group and an alkyl group having 1 to 20 carbon atoms; an unsaturated carboxylic acid ester having an aminoalkyl group having 1 to 20 carbon atoms; a vinyl ester of a saturated or unsaturated carboxylic acid having 1 to 20 carbon atoms; a vinyl cyanide compound; an unsaturated amide compound; or a monofunctional or polyfunctional (meth)acrylate of a monoalcohol or a polyhydric alcohol. The "polyhydric alcohol" may refer to an alcohol having two or more hydroxy groups, and may refer to an alcohol having 2 to 20, preferably 2 to 10, more preferably 2 to 6 hydroxy groups.

[0042] In one example, among the photocurable monomers (A), the (meth)acrylate monomer having no aromatic hydrocarbon group may be a mono(meth)acrylate, di(meth)acrylate, tri(meth)acrylate, tetra(meth)acrylate, or the like having a substituted or unsubstituted C1 to C20 (carbon number 1 to 20) alkyl group, a substituted or unsubstituted C1 to C20 alkylsilyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C1 to C20 alkylene group, an amine group, an ethylene oxide group, or the like.

[0043] Specifically, the (meth)acrylate monomer having no aromatic hydrocarbon group includes unsaturated carboxylic acid esters including (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decanyl (meth)acrylate, undecanyl (meth)acrylate, dodecyl (meth)acrylate, and cyclohexyl (meth)acrylate; unsaturated carboxylic acid amino alkyl esters such as 2-aminoethyl (meth)acrylate and 2-dimethylaminoethyl (meth)acrylate; saturated or unsaturated carboxylic acid vinyl esters such as vinyl acetate; cyanide vinyl compounds such as (meth)acrylonitrile; unsaturated amide compounds such as (meth)acrylamide; ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and the like. Glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, octanediol di(meth)acrylate, nonanediol di(meth)acrylate, decanediol di(meth)acrylate, undecanediol di(meth)acrylate, dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, penta The acrylates may include, but are not limited to, erythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, or mixtures thereof.

[0044] In one example of the present invention, the photocurable monomer (A) is a non-aromatic monomer that does not contain an aromatic group, and may include at least one of a mono(meth)acrylate having an alkyl group having 1 to 20 carbon atoms, a mono(meth)acrylate having an amine group, a di(meth)acrylate having a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a di(meth)acrylate having an ethylene oxide group, a tri(meth)acrylate having an ethylene oxide group, and a mono(meth)acrylate and di(meth)acrylate having a cyclic carbonized alkyl group.

[0045] The mono(meth)acrylate having a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms may specifically be, but is not limited to, decyl(meth)acrylate, undecyl(meth)acrylate, lauryl(meth)acrylate, tridecyl(meth)acrylate, tetradecyl(meth)acrylate, pentadecyl(meth)acrylate, hexadecyl(meth)acrylate, heptadecyl(meth)acrylate, octadecyl(meth)acrylate, nonadecyl(meth)acrylate, arachidyl(meth)acrylate, or a mixture thereof.

[0046] The mono(meth)acrylate having an amine group may be, but is not limited to, 2-aminoethyl(meth)acrylate, 2-dimethylaminoethyl(meth)acrylate, or a mixture thereof.

[0047] The di(meth)acrylate having a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms may be, for example, a di(meth)acrylate having an alkylene group having 1 to 20 carbon atoms, or may be a non-silicon di(meth)acrylate containing a substituted or unsubstituted long-chain alkylene group. The di(meth)acrylate having a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms may be, for example, octanediol di(meth)acrylate, nonanediol di(meth)acrylate, decanediol di(meth)acrylate, undecanediol di(meth)acrylate, dodecanediol di(meth)acrylate, or a mixture thereof, but is not limited thereto. When the sealing composition of the present invention contains the substituted or unsubstituted (meth)acrylate having an alkylene group having 1 to 20 carbon atoms, the photocuring rate of the sealing composition of the present invention can be further improved and the viscosity can be reduced.

[0048] The di(meth)acrylate or tri(meth)acrylate having an ethylene oxide group may specifically be, but is not limited to, ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, or a mixture thereof.

[0049] Specific examples of the mono(meth)acrylate and di(meth)acrylate having a cyclic carbonized alkyl group include, but are not limited to, isobornyl(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, dicyclopentanyl(meth)acrylate, dicyclopentenyloxyethyl(meth)acrylate, and dicyclopentenyl(meth)acrylate.

[0050] The content of the photocurable monomer (A) is preferably within a range of 55 to 95 mass %, more preferably within a range of 60 to 90 mass %, based on the total mass of the photocurable monomers (photocurable monomer (A) and photocurable monomer (B)). By ensuring that the content is within this range, the viscosity of the sealing composition of the present invention becomes appropriate for forming a sealing film for electronic devices.

[0051] <Photocurable monomer having an aromatic hydrocarbon group (B)> The photocurable monomer (B) having an aromatic hydrocarbon group (hereinafter also simply referred to as "photocurable monomer (B)") contains two or more phenyl groups and a heteroatom having a structure represented by the following general formula (1), and the photocurable monomer (B) contains at least a mono(meth)acrylate or a di(meth)acrylate: [ka]

[0052] [In the general formula (1), P represents a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups. Z 1 and Z 2 each independently has a structure represented by the following general formula (2), where a and b are each an integer of 0 to 2, and a+b is an integer of 1 to 4.

[0053] [ka]

[0054] [In the general formula (2), * represents a linking point to the carbon of P. X represents a single bond, O, or S. Y represents a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. R 1 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and c is an integer of 0 or 1.]

[0055] In the general formula (1), P represents a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups. The substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or the substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups means two or more substituted or unsubstituted phenyl groups that are not condensed and are linked by a single bond, an oxygen atom, a sulfur atom, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, an alkylene group having 3 to 6 carbon atoms substituted or unsubstituted with a heteroatom, an ethenylene group, an ethynylene group, or a carbonyl group.

[0056] For example, the hydrocarbon group containing two or more phenyl groups or the heteroatom-containing hydrocarbon group containing two or more phenyl groups may include, but are not limited to, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted triphenylmethyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted terphenylene group, a substituted or unsubstituted quaterphenylene group, a substituted or unsubstituted 2-phenyl-2-(phenylthio)ethyl group, a substituted or unsubstituted 2,2-diphenylpropane group, a substituted or unsubstituted diphenylmethane group, a substituted or unsubstituted cumylphenyl group, a substituted or unsubstituted bisphenol F group, a substituted or unsubstituted bisphenol A group, a substituted or unsubstituted biphenyloxy group, a substituted or unsubstituted terphenyloxy group, a substituted or unsubstituted quaterphenyloxy group, a substituted or unsubstituted quinquiphenyloxy group, and structural isomers thereof.

[0057] The substituted or unsubstituted monomer having two or more phenyl groups may be a mono(meth)acrylate, a di(meth)acrylate, or a mixture thereof, and examples thereof include 4-(meth)acryloxy-2-hydroxybenzophenone, ethyl-3,3-diphenyl(meth)acrylate, benzoyloxyphenyl(meth)acrylate, bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, bisphenol F di(meth)acrylate, ethoxylated bisphenol F di(meth)acrylate, and ethoxylated bisphenol F di(meth)acrylate. meth)acrylate, 4-cumylphenoxyethyl acrylate, ethoxylated bisphenylfluorene diacrylate, 2-phenylphenoxyethyl (meth)acrylate, 2,2'-phenylphenoxyethyl di(meth)acrylate, 2-phenylphenoxypropyl (meth)acrylate, 2,2'-phenylphenoxypropyl di(meth)acrylate, 2-phenylphenoxybutyl (meth)acrylate, 2,2'-phenylphenoxybutyl di(meth)acrylate, 2-(3-phenylphenyl)ethyl (meth)acrylate ) acrylate, 2-(4-benzylphenyl)ethyl (meth)acrylate, 2-phenyl-2-(phenylthio)ethyl (meth)acrylate, 2-(triphenylmethyloxy)ethyl (meth)acrylate, 4-(triphenylmethyloxy)butyl (meth)acrylate, 3-(biphenyl-2-yloxy)butyl (meth)acrylate, 2-(biphenyl-2-yloxy)butyl (meth)acrylate, 4-(biphenyl-2-yloxy)propyl (meth)acrylate, 3-(biphenyl-2-yloxy) The acryloyloxymethyl (meth)acrylate may include, but is not limited to, 4,4'-di(acryloyloxymethyl)biphenyl, 2,2'-di(2-acryloyloxyethoxy)biphenyl, structural isomers thereof, or mixtures thereof. Furthermore, the (meth)acrylates mentioned in the present invention are merely examples, and the present invention is not limited thereto. Furthermore, the present invention includes all acrylates that are structural isomers. For example, even if only 2,2'-phenylphenoxyethyl di(meth)acrylate is mentioned as an example of the present invention, the present invention also includes all structural isomers such as 3,2'-phenylphenoxyethyl di(meth)acrylate and 3,3'-phenylphenoxyethyl di(meth)acrylate.

[0058] In one example of the present invention, the monomer having two or more phenyl groups may be a mono(meth)acrylate represented by the following general formula (4).

[0059] [ka]

[0060] In the general formula (4), R 2 is hydrogen or a methyl group, and R 3 is a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, and R 4 is a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups.

[0061] For example, the above-mentioned substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or the substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups means that two or more substituted or unsubstituted phenyl groups are not condensed but are linked by a single bond, an oxygen atom, a sulfur atom, a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms, an alkylene group having 3 to 6 carbon atoms substituted or unsubstituted with a heteroatom, an ethenylene group, an ethynylene group, or a carbonyl group. For example, the substituted or unsubstituted hydrocarbon group containing two or more phenyl groups or the substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups may include, but are not limited to, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted triphenylmethyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted terphenylene group, a substituted or unsubstituted quaterphenylene group, a substituted or unsubstituted 2-phenyl-2-(phenylthio)ethyl group, a substituted or unsubstituted 2,2-diphenylpropane group, a substituted or unsubstituted diphenylmethane group, a substituted or unsubstituted cumylphenyl group, a substituted or unsubstituted bisphenol F group, a substituted or unsubstituted bisphenol A group, a substituted or unsubstituted biphenyloxy group, a substituted or unsubstituted terphenyloxy group, a substituted or unsubstituted quaterphenyloxy group, a substituted or unsubstituted quinquiphenyloxy group, and the like.

[0062] In one example of the present invention, the monomer having two or more phenyl groups may be a di(meth)acrylate represented by the following general formula (5).

[0063] [ka]

[0064] In the general formula (5), R 5 , R 9 are each independently a hydrogen atom or a methyl group, and R 6 , R 8 are each independently a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, and R 7 is a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups.

[0065] For example, the aforementioned substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or the substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups means that two or more substituted or unsubstituted phenyl groups are not condensed but are linked by a single bond, an oxygen atom, a sulfur atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, an alkylene group having 3 to 6 carbon atoms substituted or unsubstituted with a heteroatom, an ethenylene group, an ethynylene group, or a carbonyl group. For example, the hydrocarbon group may include, but is not limited to, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted triphenylmethylene group, a substituted or unsubstituted terphenylene group, a substituted or unsubstituted quaterphenylene group, a 2-phenyl-2-(phenylthio)ethylene group, a 2,2-diphenylpropylene group, a diphenylmethylene group, and the like.

[0066] In the general formula (1), a and b are each an integer of 0 to 2, and a+b is an integer of 1 to 4; in one example, a+b is an integer of 1 or 2.

[0067] The weight average molecular weight of the substituted or unsubstituted monomer having two or more phenyl groups is preferably in the range of 100 to 1000 g / mol, more preferably in the range of 130 to 700 g / mol, and particularly preferably in the range of 150 to 600 g / mol. By setting the content within the above range, it is possible to provide a sealing film with superior transmittance.

[0068] The content of the photocurable monomer (B) having an aromatic hydrocarbon group is preferably within a range of 5 to 45 mass % and more preferably within a range of 10 to 40 mass % based on the total mass of the photocurable monomers (photocurable monomer (A) and photocurable monomer (B)). By keeping the content within this range, the viscosity becomes appropriate for forming a sealing film.

[0069] <Metal-containing compounds (C)> The metal-containing compound (C) is selected from metal alkoxide compounds, metal chelate compounds, silane compounds, silazane compounds, and metal halide compounds. Examples of the metal M constituting the metal-containing compound (C) include Ti, Si, Al, Zr, silicon, bismuth, strontium, calcium, copper, sodium, and lithium. Other examples include cesium, magnesium, barium, vanadium, niobium, chromium, tantalum, tungsten, chromium, indium, and iron. At least one of Ti, Si, Al, and Zr is particularly preferred.

[0070] Specific examples of the metal-containing compound (C) are shown below, but the present invention is not limited to these. For example, tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, decyltrimethoxysilane, trimethoxysilane, trifluoropropyltrimethoxysilane, hexamethyldisilazane, perhydropolysilazane, methylpolysilazane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane , 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimeth Examples of suitable silane compounds include silane-based compounds such as dimethylsilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, 3-isocyanatepropyltriethoxysilane, tetraisocyanatesilane, and methyltriisocyanatesilane.

[0071] Alternatively, examples include organic titanium compounds having structures represented by the following general formulas (II) to (IV): In the following general formulas, R represents an alkyl group. [ka]

[0072] Further examples include organic titanium compounds such as titanium tetra-2-ethylhexoxide, titanium diisopropoxybis(acetylacetonate), titanium tetraacetylacetonate, titanium dioctyloxybis(octylene glycolate), titanium diisopropoxybis(ethylacetoacetate), titanium diisopropoxybis(triethanolaminate), titanium lactate ammonium salt, titanium lactate, titanium lactate, polyhydroxytitanium stearate, and the like.

[0073] Or, an organic zirconium compound having a structure represented by the following general formulas (V) to (VII): In the following general formula, R represents an alkyl group.

[0074] [ka]

[0075] Further examples include organic zirconium compounds such as zirconium tetra-normal propoxide, zirconium tetra-normal butoxide, zirconium tetraacetylacetonate, zirconium tributoxy monoacetylacetonate, zirconium monobutoxy acetylacetonate bis(ethylacetoacetate), zirconium dibutoxy bis(ethylacetoacetate), zirconium tetraacetylacetonate, and zirconium tributoxy monostearate.

[0076] Further examples include organic aluminum compounds such as aluminum sec-butylate, aluminum isopropylate, mono-sec-butoxyaluminum diisopropylate, aluminum ethylate, ethyl acetoacetate aluminum diisopropylate, aluminum(III) acetylacetonate, aluminum monoacetylacetonate bis(ethyl acetoacetate), aluminum-di-n-butoxide-monoethyl acetoacetate, and aluminum-di-isopropoxide-monomethyl acetoacetate.

[0077] Further examples include metal halide compounds such as titanium dichloride, titanium trichloride, titanium tetrachloride, titanium fluoride, zirconium chloride, zirconium fluoride, aluminum chloride, and aluminum fluoride.

[0078] Commercially available products of the metal-containing compound (C) include tetra(2-ethylhexyl) titanate (product name TA30, manufactured by Matsumoto Fine Chemical Co., Ltd.), aluminum sec-butylate (manufactured by Kawaken Fine Chemical Co., Ltd.), cyclic aluminum oxide isopropylate (manufactured by Kawaken Fine Chemical Co., Ltd.), titanium octylene glycol chelate (product name TC201, manufactured by Matsumoto Fine Chemical Co., Ltd.), diisopropoxybis(ethylacetoacetate)titanium (product name TC750, manufactured by Matsumoto Fine Chemical Co., Ltd.), normal butyl zirconate (product name ZA65, manufactured by Matsumoto Fine Chemical Co., Ltd.), zirconium tetraacetylacetonate (product name ZC150, manufactured by Matsumoto Fine Chemical Co., Ltd.), perhydropolysilazane (product name NN120, manufactured by AZ Chemical Co., Ltd.), and ethylpolysilazane (product name Aquamica LExp MHPS-20DB, manufactured by AZ Company) and 3-aminopropyltrimethoxysilane (product name KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) are preferably used.

[0079] The content of the metal-containing compound (C) in the entire sealing composition is not limited as long as the sealing composition maintains its photocuring function, but is preferably in the range of 0.1 to 15 mass %, more preferably in the range of 5 to 10 mass %. Furthermore, the metal-containing compound (C) may be partially transformed into an oxide or hydroxide containing the metal M. From the viewpoint of transparency, it is preferable that the molar fraction of the oxide or hydroxide of the metal M relative to the metal-containing compound (C) is within a range of 0.01 to 0.1 [mol / mol].

[0080] <Photopolymerization initiator> The photopolymerization initiator is not particularly limited as long as it is a common photopolymerization initiator that can cause a photocuring reaction. The photopolymerization initiator may include, for example, a triazine-based, acetophenone-based, benzophenone-based, thioxanthone-based, benzoin-based, phosphorus-based, oxime-based, or a mixture thereof.

[0081] Triazine initiators include 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine. , 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphth-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphth-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl(piperonyl)-6-triazine, 2,4-(trichloromethyl(4'-methoxystyryl)-6-triazine, or a mixture thereof.

[0082] The acetophenone initiator may be 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyltrichloroacetophenone, pt-butyldichloroacetophenone, 4-chloroacetophenone, 2,2'-dichloro-4-phenoxyacetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, and mixtures thereof.

[0083] The benzophenone initiator may be benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, or mixtures thereof.

[0084] The thioxanthone initiator may be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, or mixtures thereof.

[0085] The benzoin initiator may be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzil dimethyl ketal, or mixtures thereof.

[0086] The phosphorus-based initiator may be bisbenzoylphenylphosphine oxide, benzoyldiphenylphosphine oxide, or a mixture thereof.

[0087] The oxime system may be 2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(o-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone, or a mixture thereof.

[0088] The photopolymerization initiator is preferably contained in the encapsulating composition of the present invention in an amount within a range of about 0.1 to 20 parts by mass relative to 100 parts by mass of the total of the photocurable monomers (photocurable monomer (A) and photocurable monomer (B)) and the photopolymerization initiator. By setting the amount within this range, photopolymerization occurs sufficiently during exposure, and a decrease in transmittance due to remaining unreacted initiator after photopolymerization can be prevented. Specifically, the photopolymerization initiator is preferably contained in an amount of 0.5 to 10 parts by mass, more specifically, in an amount of 1 to 8 parts by mass. The photopolymerization initiator is preferably contained in the sealing composition of the present invention in an amount of 0.1 to 10 mass % based on the solid content, more preferably 0.1 to 8 mass %. By setting the amount within this range, photopolymerization can be sufficiently carried out, and a decrease in transmittance due to remaining unreacted initiator can be prevented.

[0089] Instead of the photopolymerization initiator, a photoacid generator or photopolymerization initiator such as a carbazole type, a diketone, a sulfonium type, an iodonium type, a diazo type, or a biimidazole type may be used.

[0090] <Other additives> The sealing composition of the present invention may further contain other components, including an antioxidant, a heat stabilizer, a photosensitizer, a dispersant, a thermal crosslinking agent, and a surfactant, as long as the effects of the present invention are obtained. Only one of these components may be contained in the sealing composition of the present invention, or two or more types may be contained.

[0091] The antioxidant can improve the thermal stability of the sealing layer. The antioxidant may include, but is not limited to, one or more antioxidants selected from the group consisting of phenols, quinones, amines, and phosphites. For example, examples of the antioxidant include tetrakis[methylene(3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane and tris(2,4-di-tert-butylphenyl)phosphite.

[0092] The antioxidant is contained in the sealing composition in an amount of preferably 0.01 to 3 parts by mass, more preferably 0.01 to 1 part by mass, relative to 100 parts by mass of the total of the photocurable monomer and the photopolymerization initiator. By containing the antioxidant in this range, excellent thermal stability can be exhibited.

[0093] The heat stabilizer is contained in the sealing composition and serves to suppress the change in viscosity of the sealing composition at room temperature, and any ordinary heat stabilizer can be used without any restrictions. For example, the heat stabilizer may be a sterically hindered phenolic heat stabilizer, specifically, poly(dicyclopentadiene-co-p-cresol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-4-methylphenol, 2,2'-methano-bi(4-methyl-6-tert-butyl-phenol), 6,6'-di-tert-butyl-2,2'-thiodi-p-cresol, tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, triethylene glycol-bis(3-tert-butyl-4-hydroxy-5-methylphenyl), 4,4'-thiobis(6-tert-butyl-m-cresol), 3,3'-bis(3,5-di-tert-butyl- The hydroxyethyl groups may include, but are not limited to, one or more of pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide, pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), stearyl-3,5-di-tert-butyl-4-hydroxyphenylpropionate, pentaerythritol tetrakis(1,3,5-tris(2,6-di-methyl-3-hydroxy-4-tert-butyl-benzyl)isocyanurate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, and 1,3,5-tris(2-hydroxyethyl)isocyanurate-tris(3,5-di-tert-butylhydroxyphenylpropionate).

[0094] The heat stabilizer is contained in the sealing composition in an amount of 2000 ppm or less, preferably in the range of 0.01 to 2000 ppm, more preferably in the range of 100 to 1000 ppm, based on the total amount of the photocurable monomer and the photopolymerization initiator, based on the solid content. By containing the heat stabilizer in this range, the storage stability and processability of the sealing composition in a liquid state can be further improved.

[0095] The photosensitizer has the function of transferring absorbed light energy to the photopolymerization initiator, and is therefore a compound that can impart the original photopolymerization initiator function to the photopolymerization initiator used even if the photosensitizer does not have the ability to absorb light corresponding to the light from the light source. Examples of photosensitizers include anthracene derivatives such as 9,10-dibutoxyanthracene; benzoin derivatives such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; Benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benzenemethanaminium bromide, (4-benzoylbenzyl)trimethylammonium chloride and other benzophenone derivatives; Examples of suitable compounds include thioxanthone derivatives such as 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, and 2-(3-dimethylamino-2-hydroxy)-3,4-dimethyl-9H-thioxanthone-9-one mesochloride. Among these, anthracene derivatives, benzoin derivatives, benzophenone derivatives, anthraquinone derivatives, and thioxanthone derivatives are preferred.

[0096] <UV curing> The sealing composition of the present invention is irradiated with ultraviolet light at a rate of 10 to 500 mW / cm 2 It is preferable to cure the resin by irradiating the resin for 1 to 100 seconds within the range of 1 to 100 seconds, but the curing time is not limited to this range. As the ultraviolet light, it is preferable to use a 395 nm LED from the viewpoint of preventing deterioration of electronic devices.

[0097] <Physical properties> The viscosity of the sealing composition of the present invention is preferably within a range of 3 to 20 mPa·s from the viewpoint of improving the ejection properties from an inkjet head, and the surface tension is preferably 15 mN / m or more and less than 45 mN / m from the viewpoint of improving the ejection properties from an inkjet head.

[0098] The viscosity of the sealing composition of the present invention can be determined by measuring the temperature change of the dynamic viscoelasticity of the sealing composition using, for example, various rheometers. In the present invention, these viscosities are values ​​obtained by the following method: The sealing composition of the present invention is set in a stress-controlled rheometer, Physica MCR300 (cone-plate diameter: 75 mm, cone angle: 1.0°), manufactured by Anton Paar. Next, the sealing composition is heated to 100°C and cooled to 20°C under the conditions of a temperature decrease rate of 0.1°C / s, a strain of 5%, and an angular frequency of 10 radian / s, to obtain a temperature change curve of dynamic viscoelasticity.

[0099] The sealing composition of the present invention may contain pigment particles. From the viewpoint of further improving the ejection properties from an inkjet head, when the sealing composition of the present invention contains a pigment, the pigment particles preferably have an average particle size in the range of 0.08 to 0.5 μm and a maximum particle size in the range of 0.3 to 10 μm. The average particle size of pigment particles in the present invention refers to a value determined by dynamic light scattering using a Datasizer Nano ZSP (manufactured by Malvern). Since the concentration of the sealing composition containing the colorant is high and light does not pass through this measuring device, the sealing composition is diluted 200 times before measurement. The measurement temperature is room temperature (25°C).

[0100] Furthermore, in terms of inkjet ejection properties and stabilization of ink droplets during flight, it is preferable that the Ohnesorge number (Oh) of the sealing composition of the present invention, which is calculated by the density ρ, the surface tension σ of the sealing composition, the viscosity μ of the sealing composition, and the nozzle diameter D0, and is expressed by the following formula 1, is within a range of 0.1 to 1.

[0101]

number

[0102] It is preferable to prepare the encapsulating composition of the present invention and provide a cured polymer having a Tg (glass transition temperature) of 80° C. or higher in the film after polymerization. The Tg of the film after polymerization is preferably 80° C. or higher from the viewpoint of ensuring stability in the formation process of electronic devices, operating temperatures, and reliability tests.

[0103] [Electronic device sealing film formation method] The method for forming an electronic device sealing film of the present invention is a method for forming a sealing film using the electronic device sealing composition of the present invention described above, and includes the steps of forming a first sealing layer on an electronic device by a vapor phase method, and forming a second sealing layer by applying the electronic device sealing composition on the first sealing layer. Furthermore, it is preferable to include a step of forming a third sealing layer on the second sealing layer by a vapor phase method, since this can further improve the sealing performance of the electronic device.

[0104] <First sealing layer formation process> In the first sealing layer forming step, a first sealing layer is formed on the electronic device by a vapor phase method. Examples of gas-phase methods include sputtering (including reactive sputtering methods such as magnetron cathode sputtering, planar magnetron sputtering, bipolar AC planar magnetron sputtering, and bipolar AC rotating magnetron sputtering), vapor deposition (such as resistance heating vapor deposition, electron beam vapor deposition, ion beam vapor deposition, and plasma-assisted vapor deposition), thermal CVD, catalytic chemical vapor deposition (Cat-CVD), capacitively coupled plasma CVD (CCP-CVD), photo-CVD, plasma CVD (PE-CVD), epitaxial growth, and chemical vapor deposition methods such as atomic layer deposition (ALD). Among these, ALD and CVD methods are preferred. The first sealing layer contains silicon nitride (SiN), silicon oxide (silicon monoxide, silicon dioxide, etc.), or silicon oxynitride. The thickness of the first sealing layer is, for example, preferably in the range of 10 to 1000 nm, and more preferably in the range of 100 to 500 nm.

[0105] <Second sealing layer formation process> In the second sealing layer forming step, the sealing composition of the present invention is applied onto the first sealing layer to form the second sealing layer. Specifically, the method may include a step of applying the sealing composition onto the first sealing layer (application step), and then irradiating the resulting coating film with vacuum ultraviolet light in a nitrogen atmosphere to perform a modification treatment.

[0106] (coating process) Any appropriate method can be used as a method for applying the encapsulating composition, and examples thereof include spin coating, roll coating, flow coating, inkjet coating, spray coating, printing, dip coating, film-casting, bar coating, gravure printing, etc. Among these, the inkjet method is preferred because it allows fine patterning required for encapsulating electronic devices such as organic EL elements to be performed on demand.

[0107] As the inkjet method, a known method can be used. Inkjet methods can be broadly divided into drop-on-demand methods and continuous methods, and either method can be used. Drop-on-demand methods include electro-mechanical conversion methods (e.g., single-cavity type, double-cavity type, bender type, piston type, shear-mode type, shared-wall type, etc.), electro-thermal conversion methods (e.g., thermal inkjet type, bubble jet (registered trademark) type, etc.), electrostatic suction methods (e.g., electric field control type, slit jet type, etc.), and discharge methods (e.g., spark jet type, etc.). From the standpoint of inkjet head cost and productivity, it is preferable to use an electro-mechanical conversion or electro-thermal conversion head. Note that a method of dropping droplets (e.g., coating liquid) using an inkjet method is sometimes called an "inkjet method."

[0108] The sealing composition is preferably applied in a nitrogen atmosphere.

[0109] (Modification process) The modification treatment step may include a step of irradiating the obtained coating film with vacuum ultraviolet light in a nitrogen atmosphere after the coating step to perform a modification treatment. The modification treatment refers to a reaction of converting polysilazane into silicon oxide or silicon oxynitride, and is similarly carried out in a nitrogen atmosphere or under reduced pressure, such as in a glove box. The modification treatment in the present invention can be performed by any known method based on a conversion reaction of polysilazane. In the present invention, a conversion reaction using plasma, ozone, or ultraviolet light, which can perform a conversion reaction at low temperatures, is preferred. Conventionally known methods for plasma and ozone can be used. In the present invention, the second sealing layer according to the present invention is preferably formed by providing the above-mentioned coating film and then modifying it by irradiating it with vacuum ultraviolet light (also referred to as VUV) having a wavelength of 200 nm or less.

[0110] The thickness of the second sealing layer is preferably in the range of 0.5 to 20 μm, and more preferably in the range of 3 to 10 μm. The second sealing layer may be a layer in which the entire layer is modified, but the thickness of the modified layer that has been modified is preferably in the range of 1 to 50 nm, and more preferably in the range of 1 to 30 nm.

[0111] In the step of modifying the coating film by irradiating it with vacuum ultraviolet light, the illuminance of the vacuum ultraviolet light on the surface of the coating film that the coating film receives is 30 to 200 mW / cm 2 It is preferable that the range is 50 to 160 mW / cm 2 It is more preferable that the irradiance of the vacuum ultraviolet light is within the range of 30 mW / cm. 2 By setting the power at or above this level, the reforming efficiency can be sufficiently improved, reaching 200 mW / cm 2 The following is preferable because it can significantly reduce the rate of damage to the coating film and also reduce damage to the substrate.

[0112] The irradiation energy of vacuum ultraviolet light on the coating film surface is 1 to 10 J / cm 2 From the viewpoint of barrier properties and moist heat resistance to maintain the desiccant function, it is preferable that the range is 3 to 7 J / cm 2 It is more preferable that the range is within the range of

[0113] A rare gas excimer lamp is preferably used as a light source for vacuum ultraviolet light. Vacuum ultraviolet light is absorbed by oxygen, which tends to reduce the efficiency of the vacuum ultraviolet light irradiation process. Therefore, it is preferable to perform vacuum ultraviolet light irradiation in an environment with as low an oxygen concentration as possible. That is, the oxygen concentration during vacuum ultraviolet light irradiation is preferably in the range of 10 to 10,000 ppm, more preferably in the range of 50 to 5,000 ppm, even more preferably in the range of 80 to 4,500 ppm, and most preferably in the range of 100 to 1,000 ppm.

[0114] The modification treatment can also be carried out in combination with a heat treatment. Heating conditions are preferably at a temperature in the range of 50 to 300°C, more preferably in the range of 60 to 150°C, for preferably 1 second to 60 minutes, more preferably 10 seconds to 10 minutes. By combining the heat treatment with the heat treatment, the dehydration condensation reaction during modification can be promoted, and the modified product can be formed more efficiently.

[0115] Examples of heat treatment include, but are not limited to, a method in which the substrate is brought into contact with a heating element such as a heat block to heat the coating film by thermal conduction, a method in which the atmosphere is heated by an external heater such as a resistance wire, a method using light in the infrared region such as an IR heater, etc. Furthermore, any method that can maintain the smoothness of the coating film containing a silicon compound may be appropriately selected.

[0116] <Third sealing layer formation process> In the third sealing layer forming step, a third sealing layer is formed on the second sealing layer by a vapor phase method. As with the gas phase method used in the first sealing layer formation step, examples of the gas phase method include sputtering (e.g., magnetron cathode sputtering, planar magnetron sputtering, bipolar AC planar magnetron sputtering, bipolar AC rotating magnetron sputtering, and other reactive sputtering methods), evaporation (e.g., resistance heating evaporation, electron beam evaporation, ion beam evaporation, plasma-assisted evaporation, and other), thermal CVD, catalytic chemical vapor deposition (Cat-CVD), capacitively coupled plasma CVD (CCP-CVD), photo-CVD, plasma CVD (PE-CVD), epitaxial growth, and chemical vapor deposition such as atomic layer deposition (ALD). Among these, ALD and CVD are preferred. The third sealing layer contains silicon nitride (SiN), silicon oxide (silicon monoxide, silicon dioxide, etc.), or silicon oxynitride. The thickness of the third sealing layer is, for example, preferably in the range of 10 to 1000 nm, and more preferably in the range of 100 to 500 nm.

[0117] As described above, after the sealing film is formed, a conductive film for a touch sensor may be further formed. The conductive film is, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide) In addition to metal compound films such as those mentioned above, the substrate can be made of highly flexible graphene films, metal nanowire films (e.g., films containing silver nanowires or copper nanowires), metal nanoparticle films (e.g., films containing silver nanoparticles or copper nanoparticles), etc. It can also be made of a multi-metal laminate film, such as an Al film / Ti film / Al film.

[0118] [Electronic device encapsulation film] The electronic device sealing film of the present invention is an electronic device sealing film for sealing an electronic device, and has a first sealing layer containing silicon nitride, silicon oxide, or silicon oxynitride, and a second sealing layer using the electronic device sealing composition of the present invention described above. The electronic device sealing film of the present invention is formed by the method for forming an electronic device sealing film, that is, a second sealing layer is formed using the electronic device sealing composition of the present invention. The electronic device sealing film of the present invention preferably further comprises a third sealing layer containing silicon nitride, silicon oxide or silicon oxynitride on the second sealing layer.

[0119] <First sealing layer> The first sealing layer is a layer formed on the electronic device by the vapor phase method described above, and specifically contains silicon nitride (SiN), silicon oxide (silicon monoxide, silicon dioxide, etc.), or silicon oxynitride.

[0120] <Second sealing layer> The second sealing layer is provided adjacent to the first sealing layer and is formed by applying the sealing composition onto the first sealing layer. Therefore, the second sealing layer contains a polymer having a structure represented by the following general formula (3A) and the following general formula (3B), and the metal-containing compound (C).

[0121] [ka]

[0122] [In the general formula (3A) and the general formula (3B), R1 represents a hydrogen atom or a methyl group. A has a structure that does not have an aromatic hydrocarbon group. B has an aromatic hydrocarbon group, and includes a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, having a structure represented by the general formula (1), and includes at least a mono(meth)acrylate or a di(meth)acrylate.]

[0123] In the general formula (3A) and the general formula (3B), R1 represents a hydrogen atom or a methyl group. In the general formulas (3A) and (3B), A has a structure that does not have an aromatic hydrocarbon group. That is, it has the same meaning as the photocurable monomer (A) described above, does not contain an aromatic hydrocarbon group, and may contain a monomer having 1 to 20, specifically 1 to 6, of one or more vinyl groups, acrylic groups, and methacrylic groups as photocurable functional groups, for example, 1 to 3, 1 to 2, 1, or 2 groups. In the general formula (3A) and the general formula (3B), B is a structure having an aromatic hydrocarbon group. That is, it has the same meaning as the photocurable monomer (B) described above, has an aromatic hydrocarbon group, contains two or more phenyl groups and a heteroatom having the structure represented by the general formula (1), and contains at least a mono(meth)acrylate or a di(meth)acrylate.

[0124] As a method for detecting whether the second sealing layer contains a polymer having a structure represented by general formula (3A) and general formula (3B) and the metal-containing compound (C), various conventional analytical methods can be used, such as chromatography, infrared spectroscopy, ultraviolet-visible spectroscopy, nuclear magnetic resonance analysis, X-ray diffraction, mass spectroscopy, and X-ray photoelectron spectroscopy.

[0125] The content of the metal-containing compound (C) in the second sealing layer is preferably in the range of 0.1 to 15 mass %, more preferably in the range of 5 to 10 mass %. Furthermore, the metal-containing compound (C) in the second sealing layer may be partially transformed into an oxide or hydroxide containing the metal M. From the viewpoint of transparency, it is preferable that the molar fraction of the oxide or hydroxide of the metal M relative to the metal-containing compound (C) is within a range of 0.01 to 0.1 [mol / mol].

[0126] <Third sealing layer> The third sealing layer is provided adjacent to the second sealing layer and is formed by the vapor phase method described above. Specifically, like the first sealing layer, it contains silicon nitride (SiN), silicon oxide (silicon monoxide, silicon dioxide, etc.), or silicon oxynitride.

[0127] [Electronic Devices] In the method for forming an electronic device sealing film and the electronic device sealing film of the present invention, examples of electronic devices to be sealed include organic EL elements, LED elements, liquid crystal display elements (LCDs), thin film transistors, touch panels, electronic paper, solar cells (PVs), etc. From the viewpoint of more efficiently achieving the effects of the present invention, organic EL elements, solar cells, and LED elements are preferred, and organic EL elements are particularly preferred.

[0128] <Organic EL element> The organic EL element employed as the electronic device according to the present invention may be of a bottom emission type, that is, one in which light is extracted from the transparent substrate side. Specifically, the bottom emission type is configured by laminating a transparent electrode serving as a cathode, a light emitting functional layer, and a counter electrode serving as an anode in this order on a transparent substrate. The organic EL device according to the present invention may be of a top emission type, that is, one in which light is extracted from the transparent electrode side, which serves as the cathode, opposite to the substrate. Specifically, the top-emission type has a configuration in which a counter electrode serving as an anode is provided on the substrate side, and a light-emitting functional layer and a transparent electrode serving as a cathode are laminated in this order on the surface of the counter electrode.

[0129] Representative examples of the structure of organic EL elements are shown below. (i) Anode / hole injection transport layer / light-emitting layer / electron injection transport layer / cathode (ii) Anode / hole injection transport layer / light-emitting layer / hole blocking layer / electron injection transport layer / cathode (iii) Anode / hole injection transport layer / electron blocking layer / light-emitting layer / hole blocking layer / electron injection transport layer / cathode (iv) Anode / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode (v) Anode / hole injection layer / hole transport layer / light-emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode (vi) Anode / hole injection layer / hole transport layer / electron blocking layer / light-emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode Furthermore, the organic EL device may have a non-light-emitting intermediate layer, which may be a charge generating layer or may have a multi-photon unit structure. Overviews of organic EL elements applicable to the present invention are described in, for example, JP-A-2013-157634, JP-A-2013-168552, JP-A-2013-177361, JP-A-2013-187211, JP-A-2013-191644, JP-A-2013-191804, JP-A-2013-225678, JP-A-2013-235994, and JP-A-2013-243234. Examples of the configurations described in JP-A-2013-243236, JP-A-2013-242366, JP-A-2013-243371, JP-A-2013-245179, JP-A-2014-003249, JP-A-2014-003299, JP-A-2014-013910, JP-A-2014-017493, JP-A-2014-017494, etc.

[0130] <Base material> As a substrate (hereinafter also referred to as a supporting substrate, base, substrate, support, etc.) that can be used in the organic EL element, specifically, glass or a resin film is preferably used, and when flexibility is required, a resin film is preferable. The substrate may be transparent or opaque, but in the case of a so-called bottom emission type in which light is extracted from the substrate side, the substrate is preferably transparent.

[0131] Preferred resins include substrates containing thermoplastic resins such as polyester resins, methacrylic resins, methacrylic acid-maleic acid copolymers, polystyrene resins, transparent fluororesins, polyimides, fluorinated polyimide resins, polyamide resins, polyamideimide resins, polyetherimide resins, cellulose acylate resins, polyurethane resins, polyether ether ketone resins, polycarbonate resins, alicyclic polyolefin resins, polyarylate resins, polyethersulfone resins, polysulfone resins, cycloolefin copolymers, fluorene ring-modified polycarbonate resins, alicyclic polycarbonate resins, fluorene ring-modified polyester resins, and acryloyl compounds. These resins can be used alone or in combination of two or more.

[0132] The substrate is preferably made of a heat-resistant material, specifically, a substrate having a linear expansion coefficient of 15 ppm / K to 100 ppm / K and a glass transition temperature (Tg) of 100°C to 300°C. The substrate satisfies the requirements for electronic component applications and laminate films for displays. That is, when the sealing film of the present invention is used for these applications, the substrate may be exposed to processes at 150°C or higher. In this case, if the linear expansion coefficient of the substrate exceeds 100 ppm / K, the substrate dimensions will not be stable when subjected to processes at such temperatures, and thermal expansion and contraction will cause problems such as deterioration of barrier properties or inability to withstand thermal processes. If the linear expansion coefficient is less than 15 ppm / K, the film may crack like glass, resulting in poor flexibility.

[0133] The Tg and linear expansion coefficient of the substrate can be adjusted by additives or the like. More preferred examples of thermoplastic resins that can be used as the substrate include polyethylene terephthalate (PET: 70°C), polyethylene naphthalate (PEN: 120°C), polycarbonate (PC: 140°C), alicyclic polyolefins (for example, Zeonor (registered trademark) 1600 manufactured by Nippon Zeon Co., Ltd.: 160°C), polyarylate (PAr: 210°C), polyethersulfone (PES: 220°C), polysulfone (PSF: 190°C), cycloolefin copolymers (COC: JP 2004-200666 A), and the like. Examples of suitable polycarbonates include compounds described in JP-A-2000-150584 (162°C), polyimides (e.g., Neoprim (registered trademark) manufactured by Mitsubishi Gas Chemical Company, Inc. (260°C)), fluorene ring-modified polycarbonates (BCF-PC: compounds described in JP-A-2000-227603 (225°C)), alicyclic-modified polycarbonates (IP-PC: compounds described in JP-A-2000-227603 (205°C)), and acryloyl compounds (compounds described in JP-A-2002-80616 (300°C or higher)) (the temperature in parentheses indicates Tg).

[0134] Since the electronic device according to the present invention is an electronic device such as an organic EL element, the substrate is preferably transparent. That is, the light transmittance is usually 80% or more, preferably 85% or more, and more preferably 90% or more. The light transmittance can be calculated by the method described in JIS K7105:1981, that is, by measuring the total light transmittance and the amount of scattered light using an integrating sphere light transmittance measuring device and subtracting the diffuse transmittance from the total light transmittance.

[0135] The substrates listed above may be unstretched films or stretched films. The substrates can be produced by conventionally known methods. The methods for producing these substrates may be appropriately selected from those described in paragraphs "0051" to "0055" of International Publication No. 2013 / 002026.

[0136] The surface of the substrate may be subjected to various known treatments for improving adhesion, such as corona discharge treatment, flame treatment, oxidation treatment, or plasma treatment, or may be subjected to a combination of these treatments as needed.The substrate may also be subjected to an easy-adhesion treatment.

[0137] The substrate may be a single layer or a laminated structure of two or more layers. When the substrate has a laminated structure of two or more layers, the substrates may be the same type or different types.

[0138] The thickness of the substrate according to the present invention (total thickness when it has a laminated structure of two or more layers) is preferably 10 to 200 μm, more preferably 20 to 150 μm.

[0139] In the case of a film substrate, it is preferable that the film substrate has a gas barrier layer.

[0140] The gas barrier layer for the film substrate may have an inorganic or organic coating or a hybrid coating of both formed on the surface of the film substrate, and has a water vapor permeability (25±0.5°C, relative humidity (90±2)%RH) of 0.01 g / m or less, measured by a method in accordance with JIS K 7129-1992. 2 It is preferable that the barrier film has a life of 24 hours or less, and furthermore, the oxygen permeability measured by a method in accordance with JIS K 7126-1987 is 1×10 -3 mL / m 2 24h atm or less, water vapor permeability is 1 x 10 -3 g / m 2 · It is preferable that the film has high gas barrier properties of 24 hours or less.

[0141] The material for forming the gas barrier layer may be any material that has the function of preventing the penetration of substances that cause deterioration of the element, such as moisture and oxygen, and examples of materials that can be used include silicon monoxide, silicon dioxide, silicon nitride, silicon oxynitride, silicon carbide, and silicon oxycarbide.

[0142] The gas barrier layer is not particularly limited, but in the case of an inorganic gas barrier layer such as silicon monoxide, silicon dioxide, silicon nitride, silicon oxynitride, silicon carbide, or silicon oxycarbide, it is preferable to form the layer from an inorganic material by a sputtering method (e.g., magnetron cathode sputtering, planar magnetron sputtering, bipolar AC planar magnetron sputtering, bipolar AC rotating magnetron sputtering, etc.), a vapor deposition method (e.g., resistance heating vapor deposition, electron beam vapor deposition, ion beam vapor deposition, or plasma-assisted vapor deposition), a thermal CVD method, catalytic chemical vapor deposition (Cat-CVD), capacitively coupled plasma CVD (CCP-CVD), photo-CVD, plasma CVD (PE-CVD), epitaxial growth, atomic layer deposition (ALD), reactive sputtering, or other chemical vapor deposition method.

[0143] Furthermore, inorganic gas barrier layers can also be formed by a method in which a coating liquid containing an inorganic precursor such as polysilazane or tetraethyl orthosilicate (TEOS) is applied to a support, followed by a modification treatment such as irradiation with vacuum ultraviolet light, thereby forming an inorganic gas barrier layer, or by film metallization techniques such as metal plating on a resin substrate or bonding a metal foil to a resin substrate.

[0144] The inorganic gas barrier layer may also include an organic layer containing an organic polymer, i.e., the inorganic gas barrier layer may be a laminate of an inorganic layer containing an inorganic material and an organic layer.

[0145] The organic layer can be formed, for example, by applying an organic monomer or organic oligomer to a resin substrate to form a layer, followed by polymerization and, if necessary, crosslinking using, for example, an electron beam device, a UV light source, a discharge device, or other suitable device. It can also be formed, for example, by flash evaporation and deposition of a radiation-crosslinkable organic monomer or organic oligomer, followed by forming a polymer from the organic monomer or organic oligomer. Coating efficiency can be improved by cooling the resin substrate.

[0146] Examples of methods for applying the organic monomer or organic oligomer include roll coating (e.g., gravure roll coating), spray coating (e.g., electrostatic spray coating), etc. Examples of laminates of an inorganic layer and an organic layer include the laminates described in WO 2012 / 003198 and WO 2011 / 013341.

[0147] In the case of a laminate of an inorganic layer and an organic layer, the thickness of each layer may be the same or different. The thickness of the inorganic layer is preferably within a range of 3 to 1000 nm, more preferably within a range of 10 to 300 nm. The thickness of the organic layer is preferably within a range of 100 nm to 100 μm, more preferably within a range of 1 to 50 μm. [Example]

[0148] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the following examples, unless otherwise specified, operations were carried out at room temperature (25°C). Furthermore, unless otherwise specified, "%" and "parts" mean "% by mass" and "parts by mass," respectively.

[0149] [Preparation of Sealing Compositions 1-1 to 1-78, 2-1 to 2-3, and 2-5 to 2-8] Monomer (A) and monomer (B) were weighed under nitrogen ventilation so as to have the types and parts by mass shown in Tables I to IV below. Furthermore, 5 parts by mass of a phosphorus-based photopolymerization initiator (IRGACURE TPO, manufactured by BASF) was placed in a brown bottle as a photopolymerization initiator, 0.5 parts by mass of 2-isopropylthioxanthone (manufactured by Merck) as a sensitizer, and 0.1 parts by mass of IRGASTAB UV10 (manufactured by BASF) as a stabilizer, and the mixture was stirred on a hot plate at 65°C for 3 hours. Furthermore, metal-containing compound (C) was added in the amount and parts by mass shown in Tables I to IV below, and the mixture was stirred for 1 hour to obtain sealing compositions 1-1 to 1-78, 2-1 to 2-3, and 2-5 to 2-8. However, the metal-containing compounds (C) c8 and c9 were used after dibutyl ether had been removed in advance by heating under reduced pressure using an evaporator.

[0150] [Preparation of Sealing Composition 2-4] Polysilazane (NL-120: manufactured by Clariant Japan) with a concentration of 20 mass % was used as sealing composition 2-4.

[0151] <Monomer (A)> a1: Triethylene glycol diacrylate (manufactured by SARTOMER) a2: Isoamyl acrylate (Kyoeisha Chemical Co., Ltd.) a3: Isobornyl acrylate (Kyoeisha Chemical Co., Ltd.) a4: Dicyclopentanyl acrylate (Tokyo Chemical Industry Co., Ltd.) a5: 1,10-decanediol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) a6: Triethylene glycol dimethacrylate (manufactured by BASF) a7: Lauryl acrylate (manufactured by SARTOMER) a8: Dimethylaminopropylacrylamide (Tokyo Chemical Industry Co., Ltd.) a9: EO-modified trimethylolpropane triacrylate (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)

[0152] [ka]

[0153] <Monomer (B)> b1: 2-Phenylphenoxyethyl acrylate (Shin-Nakamura Chemical Co., Ltd.) b2: (3-phenoxyphenyl)methyl prop-2-enoate (Kyoeisha Chemical Co., Ltd.) b3: the following compound X b4: Compound Y below

[0154] [ka]

[0155] The compounds X and Y were synthesized by the following methods.

[0156] (Synthesis of Compound X) A 2000 ml flask equipped with a condenser and a stirrer was charged with 800 ml of acetonitrile (Fisher), and 180 g of potassium carbonate (Sigma-Aldrich) and 108 g of acrylic acid were added at 0°C while stirring, followed by slow addition of 150 g of 4,4'-bis(chloromethyl)biphenyl (Tokyo Chemical Industry Co., Ltd.). The temperature was raised to 70°C, and the mixture was stirred for 12 hours. The acetonitrile was removed by distillation under reduced pressure, and the mixture was passed through a silica gel column to obtain 177 g of the compound X with an HPLC purity of 97%.

[0157] (Synthesis of Compound Y) A 3000 ml reactor equipped with a condenser and stirrer was charged with 300 ml of dichloromethane (Sigma-Aldrich), 200 g of 4-hydroxybutyl acrylate (Shin-Nakamura Chemical Co., Ltd.), and 168 g of triethylamine. The temperature inside the flask was lowered to 0 °C, and then a solution of 278 g of p-toluene sulfonyl chloride (Sigma-Aldrich) in 500 ml of dichloromethane was added dropwise over 2 hours while stirring. After stirring for an additional 5 hours, the remaining solvent was removed by distillation. 300 g of the resulting compound was added to 1000 ml of acetonitrile (Sigma-Aldrich), and 220 g of potassium carbonate (Sigma-Aldrich) and 141 g of 2-phenylphenol (Sigma-Aldrich) were added and stirred at 80 °C. The remaining solvent and reaction residues were removed to obtain the compound Y (molecular weight 296.36) with an HPLC purity of 93%.

[0158] <Metal-containing compounds (C)> c1: Tetra(2-ethylhexyl) titanate (product name TA30, manufactured by Matsumoto Fine Chemical Co., Ltd.) c2: Aluminum sec-butylate (Kawaken Fine Chemicals) c3: Cyclic aluminum oxide isopropylate (Kawaken Fine Chemicals Co., Ltd.) c4: Titanium octylene glycol chelate (product name TC201, manufactured by Matsumoto Fine Chemical Co., Ltd.) c5: Diisopropoxybis(ethylacetoacetate)titanium (product name TC750, manufactured by Matsumoto Fine Chemical Co., Ltd.) c6: Normal butyl zirconate (product name ZA65, manufactured by Matsumoto Fine Chemical Co., Ltd.) c7: Zirconium tetraacetylacetonate (product name ZC150, manufactured by Matsumoto Fine Chemical Co., Ltd.) c8: Perhydropolysilazane (product name NN120, manufactured by AZ Corporation) c9: Methylpolysilazane (product name: Aquamica LExp MHPS-20DB, manufactured by AZ Corporation) c10: 3-aminopropyltrimethoxysilane (product name: KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) C11: Titanium tetrachloride (Wako Pure Chemical Industries, Ltd.)

[0159] <Fabrication of Organic EL Element 1-1> (1) Preparation of the substrate A 15 μm polyimide film was prepared as the film substrate. Furthermore, a gas barrier layer for the film substrate (SiO2 film: 250 nm / SiNx film: 50 nm / SiO2 film: 500 nm (upper layer / middle layer / lower layer)) was formed on this polyimide film by plasma CVD.

[0160] (2) Formation of the first electrode An Al film was formed as a first electrode (metal layer) on one surface of the substrate under the following conditions. The thickness of the formed first electrode was 150 nm. The thickness of the first electrode was measured using a contact surface profiler (DECTAK). The Al film was deposited using a vacuum deposition device at a vacuum level of 1×10 -4 After reducing the pressure to 100 Pa, the powder was formed using a tungsten crucible for resistance heating.

[0161] (3) Formation of the organic EL layer First, the materials listed below that constitute each layer of the organic functional layer were filled into each of the evaporation crucibles in the vacuum evaporation apparatus in the optimal amounts for device fabrication. The evaporation crucibles used were made of resistance heating material made of molybdenum or tungsten.

[0162] (3-1) Formation of the hole injection layer Vacuum degree 1×10 -4 After the pressure was reduced to 10 Pa, an evaporation crucible containing the following compound A-1 was heated by applying electricity, and the compound A-1 was evaporated onto the first electrode (metal layer side) at a deposition rate of 0.1 nm / sec to form a hole injection layer with a thickness of 10 nm.

[0163] (3-2) Formation of the hole transport layer Next, the evaporation crucible containing the following compound M-2 was heated by applying current, and evaporated onto the hole injection layer at a deposition rate of 0.1 nm / sec to form a hole transport layer with a thickness of 30 nm.

[0164] (3-3) Formation of the light-emitting layer Next, the following compound BD-1 and the following compound H-1 were co-deposited at a deposition rate of 0.1 nm / sec so that the concentration of compound BD-1 was 7 mass %, to form a 15 nm-thick light-emitting layer (fluorescent-emitting layer) that emits blue light. Next, Compound GD-1 shown below, Compound RD-1 shown below, and Compound H-2 shown below were co-deposited at a deposition rate of 0.1 nm / sec so that the concentrations of Compound GD-1 and RD-1 were 20 mass % and 0.5 mass %, respectively, to form a 15 nm-thick light-emitting layer (phosphorescent-emitting layer) exhibiting a yellow color.

[0165] (3-4) Formation of the electron transport layer Then, a heating boat containing the following compound T-1 as an electron transport material was energized to form an electron transport layer made of Alq3 (tris(8-quinolinol)) on the light-emitting layer at a deposition rate of 0.1 to 0.2 nm / sec to a thickness of 30 nm.

[0166] (3-5) Formation of electron injection layer (metal affinity layer) Next, a heating boat containing the following compound I-1 as an electron injection material was heated by applying electricity to form an electron injection layer made of Liq on the electron transport layer. At this time, the deposition rate was in the range of 0.01 to 0.02 nm / sec, and the thickness was 2 nm. This electron injection layer also functions as a metal affinity layer. In this way, an organic EL layer that emits white light was formed.

[0167] [ka]

[0168] (4) Formation of the second electrode Furthermore, a Mg / Ag mixture (Mg:Ag=1:9 (vol ratio)) was evaporated to a thickness of 10 nm to form a second electrode and its extraction electrode.

[0169] (5) Formation of a capping layer The substrate was then transferred back into the vacuum chamber, and α-NPD (4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl) was evaporated onto the second electrode at a deposition rate of 0.1–0.2 nm / sec to a thickness of 40 nm, forming a capping layer for improving light extraction.

[0170] (6) Formation of the first sealing layer Next, a silicon nitride (SiN, Vickers hardness HV900) film having a thickness of 500 nm was formed by plasma CVD as a first sealing layer for covering the light-emitting portion of the organic EL element fabricated above.

[0171] (7) Formation of the second sealing layer Next, the sealing composition 1-1 prepared above was filled into the cartridge-integrated head of an inkjet device under a nitrogen environment. Then, the sealing composition 1-1 was applied to the organic EL element on which the first sealing layer had been formed using an inkjet method under a nitrogen environment. After that, 1 J / cm was applied using a 395 nm air-cooled LED (manufactured by Phoseon Technology). 2 The second sealing layer was formed by irradiating UV light for an integrated energy of 1000 kJ / cm2. The thickness of the second sealing layer was set by adjusting the number of times the inkjet was applied, and second sealing layers of the following two thicknesses were formed. 3.3μm (one application) 10μm (3 coats)

[0172] (8) Formation of the third sealing layer Next, a 500 nm thick silicon nitride (SiN, Vickers hardness HV900) was formed as a third sealing layer on the second sealing layer by plasma CVD, thereby obtaining an organic EL element 1-1 for evaluation having first to third sealing layers formed thereon.

[0173] <Preparation of Organic EL Elements 1-2 to 1-78, 2-1 to 2-3, and 2-5 to 2-8> Organic EL elements 1-2 to 1-78, 2-1 to 2-3, and 2-5 to 2-8 for evaluation were prepared in the same manner as in the preparation of organic EL element 1-1, except that the sealing composition 1-1 used in forming the second sealing layer was changed as shown in the table below.

[0174] <Fabrication of Organic EL Device 2-4> In the formation of the second sealing layer in the production of Organic EL element 1-1, sealing composition 1-1 was changed to sealing composition 2-4, and sealing composition 2-4 was applied onto the first sealing layer using a spinner set at a rotation speed of 500 rpm, followed by drying for 30 minutes at a temperature of 90° C. using a hot plate. By repeating this application and drying process, second sealing layers with two different thicknesses, 3.3 μm and 10 μm, were formed. In addition, the vapor pressure and viscosity of the sealing composition 2-4 liquid were inappropriate ranges for inkjet application, and therefore the composition could not be ejected by inkjet.

[0175] [Table 1]

[0176] [Table 2]

[0177] [Table 3]

[0178] [Table 4]

[0179] [evaluation] <Sealing performance (reliability)> Each organic EL element for evaluation was placed in a thermo-hygrostat chamber under high temperature and humidity (temperature 85°C, relative humidity 85%) to conduct an accelerated aging test. Each organic EL element was removed from the thermo-hygrostat chamber at regular intervals and allowed to emit light at room temperature. The presence or absence of dark spots (DS) during accelerated aging at 85°C and 85% humidity was confirmed. The lifespan was defined as the time until the dark spot area ratio in the luminescent region reached 0.5%, and the lifespan was evaluated. A longer lifespan indicates better sealing performance. A rank of 3 to 5 on the following evaluation criteria was considered to be acceptable. (Evaluation criteria) Rank 1: Lifespan less than 50 hours Rank 2: Lifespan 50 hours or more but less than 100 hours Rank 3: Lifespan between 100 hours and 300 hours Rank 4: Lifespan between 300 hours and 500 hours Rank 5: Lifespan of 500 hours or more

[0180] <Bending resistance> Each of the organic EL devices 1-1 to 1-67 and 2-1 to 2-7 was wrapped around a 10 mm diameter metal roller and placed in a thermo-hygrostat chamber under high temperature and humidity (temperature 60°C, relative humidity 90%) to conduct an accelerated degradation test. The polyimide film, which serves as the film substrate, was wound around the metal roller so that it was in contact with the metal roller. After 1500 hours, each organic EL device was removed from the thermo-hygrostat chamber and examined under a microscope at room temperature to confirm its light-emitting state (dark spot area ratio). A rating of 3 to 5 on the following evaluation criteria was considered acceptable. (Evaluation criteria) Rank 1: Sealing layer peeling or no light emission Rank 2: Dark spot area ratio is 1% or more Rank 3: Dark spot area ratio is 0.5% or more but less than 1% Rank 4: Dark spot area ratio is 0.1% or more but less than 0.5% Rank 5: Dark spot area ratio is less than 0.1%

[0181] <Light-emitting characteristics> The light-emitting characteristics were evaluated by comparing the light-emitting efficiency with that of a comparative organic EL element. An organic EL element for comparison was prepared by using alkali-free glass instead of the film substrate in the organic EL element prepared above. In addition, instead of forming the first, second, and third sealing layers, sealing was performed using a glass sealing can with barium oxide attached under a nitrogen atmosphere. A UV-curable adhesive was used to bond the sealing can and the substrate of the organic EL element, and the two were bonded by irradiating UV light to produce a sealed element (comparison organic EL element). The obtained comparative organic EL device and the organic EL devices 1-1 to 1-67 and 2-1 to 2-7 prepared above were subjected to a current of 2.5 mA / cm 2 The front emission spectrum was measured when a constant current of 1000 kJ / s was applied, and the luminous efficiency (lm / W) was evaluated. The measurements were performed using a spectroradiometer CS-1000 (manufactured by Konica Minolta, Inc.) The ratios of the luminous efficiency of the organic EL elements 1-1 to 1-67 and 2-1 to 2-7 to the luminous efficiency of a comparative organic EL element were evaluated according to the following evaluation criteria. Ranks 3 to 5 below were considered acceptable. (Evaluation criteria) Rank 1: Luminous efficiency below 90% Rank 2: Greater than 90% and less than 100% Rank 3: Greater than 100% and less than or equal to 110% Rank 4: Greater than 110% and less than or equal to 120% Rank 5: Greater than 120%

[0182] [Table 5]

[0183] [Table 6]

[0184] [Table 7]

[0185] [Table 8]

[0186] As shown in the above results, it can be seen that the organic EL element having a sealing layer formed using the sealing composition of the present invention has higher sealing performance, better bending resistance, and superior luminous efficiency compared to the organic EL element of the comparative example. [Industrial Applicability]

[0187] The present invention can be used in a composition for sealing an electronic device, a method for forming an electronic device sealing film, and an electronic device sealing film that can prevent moisture penetration, have excellent sealing performance and flex resistance, and further improve luminous efficiency.

Claims

1. A composition for sealing an electronic device, comprising a photocurable monomer and a photopolymerization initiator, the photocurable monomer contains a photocurable monomer (A) having no aromatic hydrocarbon group and a photocurable monomer (B) having an aromatic hydrocarbon group, The photocurable monomer (B) contains a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, and has a structure represented by the following general formula (1): the photocurable monomer (B) contains at least a mono(meth)acrylate or a di(meth)acrylate, Further, the composition contains a metal-containing compound (C) selected from a metal alkoxide compound, a metal chelate compound, and a metal halide compound, The composition for sealing electronic devices, wherein the metal M constituting the metal-containing compound (C) is at least one of Ti, Al, and Zr. 【Chemical 1】 In the general formula (1), P represents a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups. １ and Z ２ each independently has a structure represented by the following general formula (2), where a and b are each an integer of 0 to 2, and a+b is an integer of 1 to 4. 【Chemistry 2】 [In the general formula (2), * represents a linking point to the carbon of P. X represents a single bond, O, or S. Y represents a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. R １ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and c is an integer of 0 or 1.

2. 2. The composition for sealing electronic devices according to claim 1, wherein the content of the metal-containing compound (C) in the entire composition for sealing electronic devices is in the range of 0.1 to 15 mass %.

3. 3. The composition for sealing electronic devices according to claim 1, wherein the photocurable monomer (A) is at least one of a mono(meth)acrylate having an amine group, a di(meth)acrylate having a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, a di(meth)acrylate having an ethylene oxide group, a tri(meth)acrylate having an ethylene oxide group, or a mono(meth)acrylate or di(meth)acrylate having a cyclic carbonized alkyl group.

4. The photocurable monomer (B) is selected from the group consisting of 4-(meth)acryloxy-2-hydroxybenzophenone, ethyl-3,3-diphenyl(meth)acrylate, benzoyloxyphenyl(meth)acrylate, bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 2-phenylphenoxyethyl(meth)acrylate, 2,2'-phenylphenoxyethyl di(meth)acrylate, 2-phenylphenoxypropyl(meth)acrylate, 2,2'-phenylphenoxypropyl di(meth)acrylate, 2-phenylphenoxybutyl(meth)acrylate, 2,2'-phenylphenoxybutyl di(meth)acrylate, 2-(3-phenylphenyl)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate, 2-phenyl-2-(phenylthio)ethyl(meth)acrylate, 2-(triphenylmethyloxy)ethyl(meth)acrylate, 4. The composition for sealing an electronic device according to any one of claims 1 to 3, wherein the compound is any one of 4-(triphenylmethyloxy)butyl(meth)acrylate, 3-(biphenyl-2-yloxy)butyl(meth)acrylate, 2-(biphenyl-2-yloxy)butyl(meth)acrylate, 4-(biphenyl-2-yloxy)propyl(meth)acrylate, 3-(biphenyl-2-yloxy)propyl(meth)acrylate, 2-(biphenyl-2-yloxy)propyl(meth)acrylate, 4-(biphenyl-2-yloxy)ethyl(meth)acrylate, 3-(biphenyl-2-yloxy)ethyl(meth)acrylate, 2-(4-benzylphenyl)ethyl(meth)acrylate, 4,4'-di(acryloyloxymethyl)biphenyl, 2,2'-di(2-acryloyloxyethoxy)biphenyl, structural isomers thereof, and mixtures thereof.

5. A method for forming a sealing film using the composition for sealing an electronic device according to any one of claims 1 to 4, comprising: forming a first encapsulation layer on the electronic device by a vapor deposition process; and forming a second sealing layer by applying the electronic device sealing composition onto the first sealing layer.

6. The method for forming an electronic device sealing film according to claim 5 , further comprising the step of forming a third sealing layer on the second sealing layer by a vapor phase method.

7. 7. The method for forming an electronic device sealing film according to claim 5, wherein the step of forming the second sealing layer uses an inkjet method.

8. An electronic device sealing film for sealing an electronic device, a first encapsulation layer comprising silicon nitride, silicon oxide, or silicon oxynitride; An electronic device sealing film comprising: a second sealing layer formed using the electronic device sealing composition according to claim 1 .

9. 9. The electronic device sealing film according to claim 8, wherein the second sealing layer contains a polymer having a structure represented by the following general formula (3A) and the following general formula (3B), and the metal-containing compound (C). 【Chemistry 3】 [In the general formula (3A) and the general formula (3B), R １ represents a hydrogen atom or a methyl group. A has a structure that does not have an aromatic hydrocarbon group. B has an aromatic hydrocarbon group, and includes a substituted or unsubstituted hydrocarbon group containing two or more phenyl groups, or a substituted or unsubstituted heteroatom-containing hydrocarbon group containing two or more phenyl groups, having a structure represented by general formula (1), and includes at least a mono(meth)acrylate or a di(meth)acrylate.]

10. 10. The electronic device sealing film according to claim 8, further comprising a third sealing layer on the second sealing layer, the third sealing layer containing silicon nitride, silicon oxide, or silicon oxynitride.

11. The electronic device sealing film according to any one of claims 8 to 10, wherein the content of the metal-containing compound (C) in the second sealing layer is within a range of 0.1 to 15 mass%.

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