KR102578976B1 - Sealing composition - Google Patents

Abstract

The present invention provides a sealing composition containing a compound having two or more ethylenically unsaturated groups in one molecule, semi-baked hydrotalcite, and a radical polymerization initiator.

Description

Sealing composition

The present invention relates to a sealing composition, and particularly to a sealing composition suitable for sealing light-emitting devices such as organic EL (Electroluminescence) devices and light-receiving devices such as solar cells.

Organic EL devices are light-emitting devices that use organic materials as light-emitting materials, and have recently been in the spotlight because they can produce high-brightness light emission at low voltage. However, organic EL elements are extremely vulnerable to moisture, and the light-emitting material (light-emitting layer) may deteriorate due to moisture, resulting in lowered luminance or no longer emitting light, or the interface between the electrode and the light-emitting layer may peel off under the influence of moisture, or the metal may oxidize. There is a problem that the resistance becomes high. For this reason, in order to block the inside of the device from moisture in the outside air, for example, the organic EL device is sealed by forming a sealing layer with a composition to cover the entire surface of the light emitting layer formed on the substrate. The sealing layer of such an organic EL device is required to have high moisture barrier properties. Additionally, in applications such as displays, touch panels, and lighting, in the case of a structure that extracts light from the sealing surface or a transmissive structure, high transparency is also required in the sealing layer. In this way, there is a demand for a composition that can form a sealing layer that has both high moisture barrier properties and transparency.

Patent Document 1 describes a composition for adhesive encapsulation containing a hydrogenated cyclic olefin polymer and a polyisobutylene resin. Patent Document 1 describes further blending a photocurable resin and a photopolymerization initiator into the composition. Additionally, Patent Document 2 describes a curable composition containing a curable compound, a polymerization initiator, a first moisture absorbent with a water absorption of 30% by weight or more, and a second moisture absorbent with a water absorption of 5% by weight or more and less than 30% by weight. However, neither Patent Documents 1 nor 2 describe a sealing layer that achieves both high moisture barrier properties and transparency.

Japanese Patent Publication No. 2009-524705 Japanese Patent Publication No. 2016-51700

The purpose of the present invention is to provide a sealing composition capable of forming a sealing layer (cured layer) that is excellent in both moisture barrier properties and transparency.

The present inventors have conducted extensive research to achieve the above object, and as a result, a composition containing a compound having two or more ethylenically unsaturated groups in one molecule, semi-calcined hydrotalcite, and a radical polymerization initiator has moisture barrier properties and transparency. It was discovered that both sides can form an excellent sealing layer (cured material layer). The present invention based on such knowledge is as follows.

[1] A sealing composition containing a compound having two or more ethylenically unsaturated groups in one molecule, semi-baked hydrotalcite, and a radical polymerization initiator.

[2] The composition according to [1] above, wherein the compound having two or more ethylenically unsaturated groups in one molecule includes a compound having three or more ethylenically unsaturated groups in one molecule.

[3] The composition according to [1] or [2] above, wherein the compound having two or more ethylenically unsaturated groups in one molecule includes a compound having two or more ethylenically unsaturated groups and an alicyclic structure in one molecule.

[4] The composition according to any one of [1] to [3] above, further comprising a diluent.

[5] The composition according to [4] above, wherein the diluent is a compound having one ethylenically unsaturated group per molecule.

[6] The composition according to any one of [1] to [5] above, wherein the ethylenically unsaturated group is a (meth)acryloyl group.

[7] The composition according to any one of [1] to [6] above, wherein the amount of the compound having two or more ethylenically unsaturated groups per molecule is 20 to 78% by mass per entire composition.

[8] The composition according to any one of [1] to [7] above, wherein the amount of semi-calcined hydrotalcite is 10 to 70% by mass per total composition.

[9] The composition according to any one of [1] to [8] above, wherein the radical polymerization initiator is a photo-radical polymerization initiator and/or a thermal radical polymerization initiator.

[10] The composition according to any one of [1] to [9] above, wherein the amount of the radical polymerization initiator is 0.5 to 10 parts by mass based on 100 parts by mass of the compound having an ethylenically unsaturated group.

[11] The composition according to any one of [1] to [10] above, further comprising a silane coupling agent.

[12] The composition according to any one of [1] to [11] above, wherein the total light transmittance of the cured layer of the composition having a thickness of 20 μm to D65 light is 85% or more.

[13] The composition according to any one of [1] to [12] above, wherein the haze of the cured layer of the composition having a thickness of 20 μm is less than 3.0%.

[14] The composition according to any one of [1] to [13] above, which is in a liquid form.

[15] The composition according to any one of [1] to [14] above, which is for sealing an organic EL device.

[16] An organic EL device in which an organic EL element is sealed with a cured product of the composition according to any one of [1] to [15] above.

From the composition of the present invention, a sealing layer excellent in both moisture barrier properties and transparency can be formed.

<Composition>

The composition of the present invention contains a compound having two or more ethylenically unsaturated groups in one molecule, semi-calcined hydrotalcite, and a radical polymerization initiator. Here, “ethylenically unsaturated group” means a functional group having an ethylenic double bond. The composition of the present invention can be produced by mixing the above components and, if necessary, other components using a kneading roller, rotary mixer, or the like.

The composition of the present invention is used, for example, for sealing electronic components such as semiconductors, solar cells, high-brightness LEDs, LCDs, and EL devices, and preferably optical semiconductors such as organic EL devices and solar cells. The composition of the present invention is particularly suitably used for sealing organic EL devices. Specifically, the composition of the present invention can be used to protect the light-emitting part of an organic EL element from the outside by applying it to the top and/or surroundings (sides) of the light-emitting part of the organic EL element.

The composition of the present invention is preferably a liquid sealing composition. Here, “liquid sealing composition” means a sealing composition that has fluidity at room temperature (25°C) and normal pressure (1 atm). For example, a sealing composition containing an inorganic filler also corresponds to a liquid sealing composition in the present invention if it has fluidity at room temperature and pressure. Compared to film-shaped sealing materials, liquid sealing materials (sealing compositions) generally have the following advantages: embedding ability in the surface of a light emitting element having a circuit, suppression of voids when the sealing surface is large, ease of adjustment of the film thickness of the sealing layer, and sealing. It is often advantageous in terms of high alignment precision achieved by forming the dam before and adjusting its position.

It is preferable that the composition of the present invention does not contain volatile components such as solvents. In addition, when the composition of the present invention contains volatile components such as solvents, volatile components such as solvents are not included in the standard for the amount of each component. That is, when the composition of the present invention contains volatile matter, “the total sugar of the composition”, which is the standard for the amount of each component, means “the total sugar of the non-volatile matter of the composition.”

<Compounds having two or more ethylenically unsaturated groups in one molecule>

The composition of the present invention contains a compound having two or more ethylenically unsaturated groups in one molecule (hereinafter sometimes abbreviated as “polyfunctional ethylenically unsaturated compound”). The polyfunctional ethylenically unsaturated compound may be used individually or in combination of two or more types. The polyfunctional ethylenically unsaturated compound may contain other functional groups such as an epoxy group, as long as the effect of the present invention is exhibited. In addition, in the present invention, polyfunctional ethylenically unsaturated compounds containing an epoxy group are classified as polyfunctional ethylenically unsaturated compounds, not epoxy resins.

The polyfunctional ethylenically unsaturated compound is preferably in a liquid form in order to make the sealing composition of the present invention in a liquid form. Here, “liquid phase” refers to the state of a polyfunctional ethylenically unsaturated compound at room temperature (25°C) and normal pressure (1 atm). When the polyfunctional ethylenically unsaturated compound is a mixture of two or more types of compounds, it is preferable that these mixtures are in a liquid state. For example, when using a solid polyfunctional ethylenically unsaturated compound and a liquid polyfunctional ethylenically compound, it is preferable that the mixture of these compounds is liquid.

From the viewpoint of forming a high-density crosslinked structure and exhibiting high moisture barrier properties, the polyfunctional ethylenically unsaturated compound is preferably a compound having 3 or more ethylenically unsaturated groups per molecule, and more preferably 4 per molecule. It includes compounds having at least 5 ethylenically unsaturated groups, more preferably at least 5 ethylenically unsaturated groups in one molecule, and particularly preferably at least 6 ethylenically unsaturated groups in one molecule. In the polyfunctional ethylenically unsaturated compound, the upper limit of the number of ethylenically unsaturated groups contained in one molecule is not particularly limited, but the number is preferably 15 or less, more preferably 12 or less, and still more preferably 10. It is as follows.

When using a compound having 3 or more ethylenically unsaturated groups in one molecule, the amount is preferably 2% by mass or more, more preferably 3% by mass or more, per entire composition, from the viewpoint of demonstrating high moisture barrier properties. , more preferably 4% by mass or more, preferably 70% by mass or less, more preferably 65% by mass or less, and even more preferably 60% by mass or less.

From the viewpoint of improving moisture barrier properties, the polyfunctional ethylenically unsaturated compound is preferably a compound having two or more ethylenically unsaturated groups and an alicyclic structure in one molecule, and more preferably two ethylenically unsaturated groups in one molecule. and compounds having an alicyclic structure. Examples of the alicyclic structure include structures having an alicyclic hydrocarbon ring having 5 to 12 carbon atoms. Examples of alicyclic hydrocarbon rings include tricyclo[5.2.1.0 ^2,6 ] decane ring, bornane ring, isobornane ring, cyclohexane ring, bicyclooctane ring, norbornene ring, cyclodecane ring, adamantane ring, Cyclopentane, etc. can be mentioned. The alicyclic structure may have a hetero atom. Additionally, the alicyclic structure may have a substituent such as an alkyl group, an alkoxy group, or an alkylene group bonded thereto.

When using a compound having two or more ethylenically unsaturated groups and an alicyclic structure in one molecule (particularly, a compound having two ethylenically unsaturated groups and an alicyclic structure in one molecule), the amount is preferably per composition. Preferably it is 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, preferably 75% by mass or less, more preferably 70% by mass or less, and even more preferably 65% by mass. It is as follows.

As the ethylenically unsaturated group, a (meth)acryloyl group is preferable. That is, as the compound having an ethylenically unsaturated group, (meth)acrylate having a (meth)acryloyl group is preferable. In this specification, “(meth)acryloyl group” means “acryloyl group and/or methacryloyl group”, and “(meth)acrylate” means “acrylate and/or methacrylate”. it means. In addition, (meth)acrylate having two or more (meth)acryloyl groups in one molecule may hereinafter be abbreviated as “polyfunctional (meth)acrylate”. Additionally, (meth)acrylate having two (meth)acryloyl groups in one molecule is sometimes abbreviated as “bifunctional (meth)acrylate”.

As the multifunctional (meth)acrylate, an oligomer may be used. Examples of oligomers include polyester oligomers synthesized by the reaction of polyester polyol and acrylic acid, urethane oligomers with urethane bonds, epoxy oligomers synthesized by the reaction of glycidyl ether with acrylic acid or acrylate with a carboxyl group, etc. can be mentioned.

As bifunctional (meth)acrylates, for example, “DPGDA” (dipropylene glycol diacrylate), “HDDA” (1,6-hexanediol diacrylate), and “TPGDA” (trimethylcellulose) manufactured by Daicel Ornex. propylene glycol diacrylate), “EBECRYL145” (PO modified neopentyl glycol diacrylate), “EBECRYL150” (modified bisphenol A diacrylate), “IRR214-K” (tricyclodecane dimethanol diacrylate), “ “EBECRYL11” (PEG600 diacrylate), “HPNDA” (neopentyl glycol hydroxypivalic acid ester diacrylate), “Light Ester EG” (ethylene glycol dimethacrylate) manufactured by Kyoeisha Chemical Co., Ltd., “Light Ester NP” -A” (neopentylglucol dimethacrylate), “Light Ester 2EG” (Diethylene glycol dimethacrylate), “Light Ester 1.6HX” (1,6-hexanediol dimethacrylate), “Light Ester 2EG” (Diethylene glycol dimethacrylate), “Light Ester 1.6HX” (1,6-hexanediol dimethacrylate) “Ester 1.9ND” (1,9-nonanediol dimethacrylate), “Light ester G-101P” (glycerin dimethacrylate), “Light ester BP-2EMK” (EO adduct dimethacrylate of bisphenol A) ), “Light Acrylate NP-A” (neopentyl glycol diacrylate), “Light Acrylate 1.9ND-A” (1,9-nonanediol diacrylate), “Light Acrylate BP-4EAL” (bisphenol EO adduct diacrylate of A)”, “Light acrylate BP-4PA” (PO adduct diacrylate of bisphenol A), “NK Ester 701A” (2-hydroxy-3) manufactured by Shinnakamura Kagakukogyo Co., Ltd. -Methacrylpropyl acrylate), “NK Ester A-200” (polyethylene glycol #200 diacrylate), “NK Ester APG-400” (polypropylene glycol #400 diacrylate), “NK Ester A-PTMG- 65” (polytetramethylene glycol #650 diacrylate), “NK ester A-1206PE” (polyethylene polypropylene glycol diacrylate), “NK ester ester A-BPEF” (9,9-bis[4-(2) -Hydroxyethoxy)phenyl]fluorene diacrylate), “NK ester ester A-BPE 30” (ethoxylated bisphenol A diacrylate), “NK ester A-BPP-3” (propoxylated bisphenol A diacrylate) acrylate), “NK ester BG” (1,3-butanediol dimethacrylate), “NK ester 701” (2-hydroxy-1,3-dimethacryloxypropane), “NK ester 3PG” (trimethacrylate) Propylene glycol dimethacrylate), “NK ester ester ester 1206PE” (polyethylene polypropylene glycol dimethacrylate), “NK ester DCP” (tricyclodecane dimethanol dimethacrylate), “KAYARAD FM manufactured by Nippon Kayaku Co., Ltd. -400”, “KAYARAD HX-220”, “KAYARAD HX-620” (neopentyl modified diacrylate), “KAYARAD R-604” (dioxane glycol diacrylate), “KAYARAD UX-3204” (1 molecule oligomer having two acrylic groups in the middle), Osaka Yuki Kagakukogyo Co., Ltd. “Viscoto #195” (1,4-butanediol diacrylate), “Viscoto #540” (bisphenol A diglycidyl ether acrylic acid adduct) ), “CD406” (cyclohexanedimethanol diacrylate) manufactured by Arkema, “SR562” (alkoxylated hexanediol diacrylate), “EBECRYL600” manufactured by Daicel Ornex (two acryloyl groups per molecule) bisphenol A type epoxy acrylate), “EBECRYL210” (aromatic urethane oligomer with two acryloyl groups in one molecule), “EBECRYL230” (aliphatic urethane oligomer with two acrylic groups in one molecule), “EBECRYL436” ( ester oligomer having two acrylic groups in one molecule), “CN959” manufactured by Arkema (urethane oligomer having two acrylic groups in one molecule), “Artresine UN-9000PEP” manufactured by Nekami Kogyo Co., Ltd. (two acrylic groups in one molecule) and “Artrezine UN-333” (urethane oligomer having a loyl group) (oligomer having two acrylic groups in one molecule).

Examples of (meth)acrylates having three or more (meth)acryloyl groups in one molecule include “Light Ester TMP” (trimethylolpropane trimethacrylate) manufactured by Koesha Chemical Co., Ltd. and “Light Acrylate PE”. -3A” (pentaerythritol triacrylate), “light acrylate PE-4A” (pentaerythritol tetraacrylate), “light acrylate DGE-4A” (EO adduct-modified diglycerol tetraacrylate), Daicel Orr "PETIA" (pentaerythritol (tri/tetra)acrylate), TMPTA (trimethylolpropane triacrylate), TMPEOTA (trimethylolpropane ethoxy triacrylate), "EBECRYL135" (trimethylolpropane propoxy triacrylate) manufactured by Nex Corporation Acrylate) “PETA” (pentaerythritol (tri/tetra)acrylate), “DPHA” (dipentaerythritol hexaacrylate), “NK Ester A-TMPT” (trimethylolpropane triacrylate) manufactured by Shinnakamura Kagakukogyo Co., Ltd. rate), “NK ester A-TMPT-3PO” (propoxylated trimethylolpropane triacrylate), “NK ester A-GLY-6E” (ethoxylated glycerin triacrylate), “NK ester A-GLY-6P "(Propoxylated glycerin triacrylate), "NK Ester A-9300" (Tris-(2-acryloxyethyl)isocyanurate), "NK Ester A-9200" (Bis/Tris-(2-acrylate) oxyethyl)isocyanurate), “NK ester A-9300-1CL” (caprolactone modified tris-(2-acryloxyethyl)isocyanurate), “NK ester ATM-4EL” (ethoxylated pentaerythritol ( tri/tetra)acrylate), “KAYARAD DPCA-20” (hexa-functional acrylate) manufactured by Nippon Kayaku Co., Ltd., “KAYARAD DPCA-60” (hexa-functional acrylate), “T-1420(T)” (tetra-functional acrylate) rate), “DPEA-12” (hexa-functional acrylate), “KAYARAD DPHA-40H” (oligomer having 10 acryloyl groups in one molecule), “Viscoto #802” (Penta) manufactured by Osaka Yuki Kagakukogyo Co., Ltd. Erythritol acrylate), “Viscot #1000” (dendrimer acrylate), “CN989NS” manufactured by Arkema (aliphatic urethane oligomer with 3 acryloyl groups per molecule), “CN9039” (6 acryloyl groups per molecule) aliphatic urethane oligomer having a single group), “UN-3320HA”, “UN-3320HC”, and “UN-906S” (aliphatic urethane oligomer having 6 acryloyl groups in one molecule) manufactured by Nekami Kogyo Co., Ltd., “DICLITE” manufactured by DIC Corporation UE-8740” (phenol novolak-type epoxy acrylate having three acryloyl groups in one molecule), etc. Additionally, “pentaerythritol (tri/tetra)acrylate” means a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate. Other words such as “(tree/tetra)” also have the same meaning.

As a polyfunctional (meth)acrylate having an alicyclic structure, for example, "IRR214-K" (tricyclodecane dimethanol) manufactured by Daicel Ornex, which has a tricyclo[5.2.1.0 ^2,6 ] decane ring structure diacrylate), 1,3-adamantanediol diacrylate manufactured by Mitsubishi Gas Chemical Co., Ltd., etc.

The amount of the polyfunctional ethylenically unsaturated compound is preferably 20 to 78% by mass, more preferably 25 to 75% by mass, and even more preferably 30 to 70% by mass, per the entire composition.

<Compound having one ethylenically unsaturated group in one molecule>

The sealing composition of the present invention contains a compound having one ethylenically unsaturated group per molecule (hereinafter sometimes abbreviated as “monofunctional ethylenically unsaturated compound”). As will be described later, the “monofunctional ethylenically unsaturated compound” may be included in the sealing composition of the present invention as a diluent. The monofunctional ethylenically unsaturated compound may contain other functional groups such as an epoxy group, as long as the effect of the present invention is exhibited. Examples of such compounds include compounds having one or more epoxy groups and one ethylenically unsaturated group in one molecule. In addition, in the present invention, monofunctional ethylenically unsaturated compounds containing an epoxy group are classified as monofunctional ethylenically unsaturated compounds, not epoxy resins.

Commercially available compounds having an epoxy group and one ethylenically unsaturated group per molecule include, for example, “Cycloma M100” (3,4-epoxycyclohexylmethyl methacrylate) and “UVACURE1561” (epoxy group) manufactured by Daicel Ornex. and a mixture of a compound having one acryloyl group in one molecule (content: 78 to 82% by mass) and a bisphenol A type epoxy resin (content: 18 to 22% by mass), “4HBAGE” (4- Hydroxybutylacrylate glycidyl ether) etc. can be mentioned.

When the sealing composition of the present invention contains a monofunctional ethylenically unsaturated compound, the amount is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 1.5% by mass or more, per the total composition. , and is preferably 55 mass% or less, more preferably 50 mass% or less, and even more preferably 40 mass% or less.

<Compounds having an ethylenically unsaturated group>

The above-mentioned “polyfunctional ethylenically unsaturated compound” and “monofunctional ethylenically unsaturated compound” are collectively described as “compound having an ethylenically unsaturated group.” The amount of the compound having an ethylenically unsaturated group is preferably 30 to 80% by mass, more preferably 35 to 80% by mass, and still more preferably 40 to 80% by mass, per the entire composition.

<Diluent>

The sealing composition of the present invention is a liquid sealing composition and may contain a diluent to achieve an appropriate viscosity. The viscosity of the diluent measured at a temperature of 25°C with a type B viscometer is preferably 0.1 to 5000 mPa·s, more preferably 0.1 to 2500 mPa·s, and still more preferably 0.1 to 1000 mPa·s.

As a diluent, a reactive diluent is preferred. As a reactive diluent, a compound having one ethylenically unsaturated group per molecule (hereinafter sometimes abbreviated as “monofunctional ethylenically unsaturated compound”) is preferable.

In addition, compounds having two ethylenically unsaturated groups in one molecule (hereinafter sometimes abbreviated as "bifunctional ethylenically unsaturated compounds") classified as "polyfunctional ethylenically unsaturated compounds" in the present invention have a viscosity range of the above. In some cases, it also functions as a reactive diluent. When blending a bifunctional ethylenically unsaturated compound that also functions as a reactive diluent, the blending amount can be reduced accordingly by not blending the diluent or even when blending it. Examples of bifunctional ethylenically unsaturated compounds that also function as diluents include “DPGDA” (dipropylene glycol diacrylate), “HDDA” (1,6-hexanediol diacrylate), and “TPGDA” (tripropylene glycol). diacrylate), “EBECRYL145” (PO modified neopentyl glycol diacrylate), “HPNDA” (neopentyl glycol hydroxypivalic acid ester diacrylate), “Light Ester NP” (neopentyl) manufactured by Kyoeisha Chemical Co., Ltd. Glucol Dimethacrylate), “Light Ester EG” (Ethylene Glycol Dimethacrylate), “Light Ester 2EG” (Diethylene Glycol Dimethacrylate), “Light Ester 1.6HX” (1,6-hexanediol dimethacrylate), “light ester 1.9ND” (1,9-nonanediol dimethacrylate), “light acrylate NP-A” (neopentyl glycol diacrylate), “light acrylate 1.9ND-A” "(1,9-nonanediol diacrylate), "NK Ester 701A" (2-hydroxy-3-methacrylpropyl acrylate) manufactured by Shinnakamura Chemical Co., Ltd., "NK Ester A-200" (polyethylene glycol) #200 diacrylate), “NK ester APG-400” (polypropylene glycol #400 diacrylate), “NK ester BG” (1,3-butanediol dimethacrylate), “NK ester 701” (2- Hydroxy-1,3-dimethacryloxypropane), “NK Ester 3PG” (tripropylene glycol dimethacrylate), “Viscoto #195” (1,4-butanediol diacrylate) manufactured by Osaka Yuki Kagaku Kogyo Co., Ltd. rate), “SR562” (alkoxylated hexanediol diacrylate) manufactured by Arkema, etc. The ethylenically unsaturated group is preferably a (meth)acryloyl group, and the reactive diluent is particularly preferably a (meth)acrylate having one (meth)acryloyl group per molecule (hereinafter referred to as “monofunctional (meth)acrylic”). (sometimes abbreviated as “rate”).

Examples of monofunctional (meth)acrylates used as diluents include “ODA-N” (octyl/decyl acrylate, i.e., monofunctional acrylate with a long-chain alkyl group) manufactured by Daicel Ornex, and “EBECRYL 110.” , “EBECRYL1114” (ethoxylated phenylacrylate), “Light Ester E” (ethyl methacrylate) manufactured by Kyoeisha Chemical Co., Ltd., “Light Ester NB” (n-butyl methacrylate), “Light Ester IB” ( Isobutyl methacrylate), “Light ester TB” (t-butyl methacrylate), “Light ester EH” (2-ethylhexyl methacrylate), “Light ester ID” (isodecyl methacrylate), “ “Light ester L” (n-lauryl methacrylate), “Light ester S” (n-stearyl methacrylate), “Light ester CH” (cyclohexyl methacrylate), “Light ester THF (1000)” (tetrahydrofurfuryl methacrylate), “light ester BZ” (benzyl methacrylate), “light ester PO” (benzylphenoxyethyl methacrylate), “light ester IB-X” (isobornyl methacrylate) rate), “light ester HO-250” (2-hydroxyethyl methacrylate), “light ester HOA” (hydroxyethyl acrylate), “light ester G” (glycidyl methacrylate), “light Acrylate IAA" (isoamyl acrylate, that is, monofunctional acrylate with a branched alkyl group), "light acrylate S-A" (stearyl acrylate), "light acrylate EC-A" (ethoxy-diethylene glycol acrylate) rate), “light acrylate EHDG-AT” (2-ethylhexyl-diglycol acrylate), “light acrylate DPM-A” (methoxydipropylene glycol acrylate), “light acrylate IB-XA” (isopropylene glycol acrylate) Bornyl methacrylate, i.e., monofunctional methacrylate having an alicyclic group), “light acrylate PO-A” (phenoxyethyl acrylate, i.e., monofunctional acrylate having an aromatic ring), “light acrylate P2H” -A” (phenoxydiethylene glycol acrylate), “light acrylate P-200A” (phenoxy-polyethylene glycol acrylate), “light acrylate POB-A” (m-phenoxybenzyl acrylate), “light Acrylate TFH-A” (tetrahydrofurfuryl acrylate), “Light ester HOP-A (N)” (2-hydroxypropyl acrylate), “HOA-MS(N)” (2-acryloyloxy Ethyl-succinic acid), “Epoxy ester M-600A” (2-hydroxy-3-phenoxypropylacrylate), “IDAA” (isodecyl acrylate) manufactured by Osaka Yuki Kakagukogyo Co., Ltd., “Viscoto #155” ( Cyclohexyl acrylate), “Viscot #160” (benzyl acrylate), “Viscot #150” (tetrahydrofurfuryl acrylate), “Viscot #190” (ethylcarbitol acrylate), “OXE- 10” (3-ethyl-3-oxetanylmethyl acrylate, that is, acrylate having an oxetane ring), “MEDOL-10” (2-methyl-2-ethyl-1,3-dioxolan-4-yl ) Methyl acrylate, i.e., acrylate having a dioxolane ring), “Aronix M-101A” (phenol EO modified acrylate) manufactured by Toa Kosei Co., Ltd., NK Ester A-LEN-10” manufactured by Shinnakamura Kagaku Kogyo Co., Ltd. (ethoxylated o-phenylphenol acrylate), “NK Ester EH-4E” (ethoxylated hexylpolyethylene glycol methacrylate), “FA-511AS” (dicyclopentenyl acrylate) manufactured by Hitachi Kasei Corporation, “FA- 512AS" (dicyclopentenyloxyethyl acrylate), "FA-513AS" (dicyclopentanyl acrylate), "SR217NS" (4-tert-butylcyclohexanol acrylate) manufactured by Arkema, "SR420NS" (3 , 3,5-trimethylcyclohexanol acrylate), “SR531” (cyclic trimethylolpropane formal acrylate), “CD421” (3,3,5-trimethylcyclohexanol methacrylate), “CD535” ( Dicyclopentadienyl methacrylate), “VEEA” (2-(2-vinyloxyethoxy)ethyl acrylate) manufactured by Nippon Shokubai Co., Ltd., “VEEM” (2-(2-vinyloxyethoxy) methacrylate) ethyl) and the like. Additionally, “octyl/decyl acrylate” means a mixture of octyl acrylate and decyl acrylate.

As the monofunctional (meth)acrylate used as a diluent, monofunctional methacrylate having an alicyclic structure is particularly preferable. The alicyclic structure is identical to the one described above. Commercially available monofunctional (meth)acrylates having an alicyclic structure include, for example, “Light Ester IB-X” (isobornyl methacrylate), manufactured by Kyoeisha Chemical Co., Ltd. and “Light Acrylic,” which have a bornane ring structure. “Rate IB-XA” (isobornyl methacrylate), “Light Ester CH” (cyclohexyl methacrylate) manufactured by Kyoeisha Chemical Co., Ltd., which has a cyclohexyl structure, and “Viscoto #155” manufactured by Osaka Yuki Kakagukogyo Co., Ltd. (cyclohexyl acrylate), “SR217NS” (4-tert-butylcyclohexanol acrylate) manufactured by Arkema, “SR420NS” (3,3,5-trimethylcyclohexanol acrylate), “CD421” (3, 3,5-trimethylcyclohexanol methacrylate), “CD535” (dicyclopentadienyl methacrylate), “FA-511AS” (dicyclopentenyl acrylate) manufactured by Hitachi Kasei, which has a dicyclo ring structure. , “FA-512AS” (dicyclopentenyloxyethyl acrylate), “FA-513AS” (dicyclopentanyl acrylate), “CD535” (dicyclopentadienyl methacrylate) manufactured by Arkema Corporation, Nippon Shokuba Co., Ltd. “VEEA” (2-(2-vinyloxyethoxy)ethyl acrylate) and “VEEM” (2-(2-vinyloxyethoxy)ethyl methacrylate) manufactured by Isa Corporation.

When a diluent is used, the amount (including the amount when a "bifunctional ethylenically unsaturated compound" functioning as a diluent is included) is preferably 2% by mass or more, more preferably 5% by mass, per total composition. or more, more preferably 10 mass% or more, preferably 60 mass% or less, more preferably 55 mass% or less, even more preferably 50 mass% or less.

<Semi-fired hydrotalcite>

The composition of the present invention includes semi-baked hydrotalcite. There may be only one type of semi-fired hydrotalcite, or two or more types may be used.

Hydrotalcite can be classified into uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite.

Uncalcined hydrotalcite is a metal hydroxide with a layered crystal structure, as represented by natural hydrotalcite (Mg ₆ Al ₂ (OH) ₁₆ CO ₃ ·4H ₂ O), for example, _It consists _{of the} basic skeleton layer [ _{Mg 1 -} ^{X Al} The concept of uncalcined hydrotalcite in the present invention includes hydrotalcite-like compounds such as synthetic hydrotalcite. Examples of hydrotalcite-like compounds include those represented by the following formula (I) and the following formula (II).

[M ²⁺ _1-x M ³⁺ x(OH) ₂ ] ^x+ ·[(A ^n- ) _x/n ·mH ₂ O] ^x- (I)

(In the formula, M ²⁺ represents a divalent metal ion such as Mg ²⁺ and Zn ²⁺ , M ³⁺ represents a trivalent metal ion such as Al ³⁺ and Fe ³⁺ , and A ^n- represents CO ₃ Represents n-valent anions such as ^2- , ^Cl- , NO _3- ^, etc., 0<x<1, 0≤m<1, and n is a positive number.)

In formula (I), M ²⁺ is preferably Mg ²⁺ , M ³⁺ is preferably Al ³⁺ , and A ^n- is preferably CO ₃ ^2- .

M ²⁺ _x Al ₂ (OH) _2x+6-nz (A ^n- ) _z ·mH ₂ O (II)

(In the formula, M ²⁺ represents a divalent metal ion such as Mg ²⁺ or Zn ²⁺ , A ^n- represents an n-valent anion such as CO ₃ ^2- , Cl ^- , NO ^3- , and x is 2 is a positive number greater than or equal to 2, z is a positive number less than or equal to 2, m is a positive number, and n is a positive number.)

In formula (II), M ²⁺ is preferably Mg ²⁺ and A ^n- is preferably CO ₃ ^2- .

Semi-calcined hydrotalcite refers to a metal hydroxide obtained by calcining uncalcined hydrotalcite and having a layered crystal structure in which the amount of interlayer water is reduced or lost. When explained using the composition formula, “interlayer water” refers to “H ₂ O” described in the composition formula of the above-mentioned uncooked natural hydrotalcite and hydrotalcite-like compound. One of the features of the present invention is that this semi-calcined hydrotalcite is used.

On the other hand, calcined hydrotalcite refers to a metal oxide obtained by calcining uncalcined or semi-calcined hydrotalcite and having an amorphous structure in which not only interlayer water but also hydroxyl groups are lost by condensation dehydration.

Uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished according to their saturation water absorption. The saturated water absorption of semi-baked hydrotalcite is 1 mass% or more and less than 20 mass%. On the other hand, the saturated water absorption of uncalcined hydrotalcite is less than 1 mass%, and the saturated water absorption of calcined hydrotalcite is 20 mass% or more.

In the present invention, “saturated water absorption rate” means weighing 1.5 g of uncalcined hydrotalcite, semi-calcined hydrotalcite, or calcined hydrotalcite on a balance, measuring the initial mass, and then measuring the initial mass at atmospheric pressure, 60°C, 90%RH (relative This refers to the mass increase rate relative to the initial mass when left in a small environmental tester (SH-222 manufactured by Espec) set to humidity for 200 hours, and is expressed in the following equation (i):

Saturated absorption rate (mass%)

=100×(mass after absorption-initial mass)/initial mass (i)

It can be obtained with

The saturated water absorption of the semi-calcined hydrotalcite is preferably 3% by mass or more and less than 20% by mass, more preferably 5% by mass or more and less than 20% by mass.

Additionally, uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by the thermogravimetric reduction rate measured by thermogravimetric analysis. The thermal weight reduction rate of semi-baked hydrotalcite at 280°C is less than 15% by mass, and the thermal weight reduction rate at 380°C is 12% by mass or more. On the other hand, the thermal weight reduction rate of uncalcined hydrotalcite at 280°C is 15% by mass or more, and the thermal weight reduction rate of calcined hydrotalcite at 380°C is less than 12% by mass.

For thermal mass spectrometry, 5 mg of hydrotalcite was weighed into an aluminum sample pan using TG/DTA EXSTAR6300 manufactured by Hitachi High-Tech Science, Inc., and the lid was left open in an atmosphere with a nitrogen flow rate of 200 mL/min for 30 mL/min. It can be carried out from ℃ to 550℃ under the condition of a temperature increase rate of 10℃/min. The thermal weight loss rate is expressed by the following formula (ii):

Thermal weight reduction rate (mass%)

=100×(mass before heating-mass when reaching predetermined temperature)/mass before heating (ii)

It can be obtained with

Additionally, uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by peaks and relative intensity ratios measured by powder X-ray diffraction. Semi-calcined hydrotalcite shows a peak split into two at 2θ around 8 to 18° by powder Or, the relative intensity ratio (low-angle side diffraction intensity/high-angle side diffraction intensity) of the diffraction intensity of the shoulder (=low-angle side diffraction intensity) and the diffraction intensity of the peak or shoulder appearing on the high-angle side (=high-angle side diffraction intensity) is 0.001 to 0.001. It's 1,000. On the other hand, uncalcined hydrotalcite has only one peak around 8 to 18°, or the relative intensity ratio of the diffraction intensity of the peak or shoulder appearing on the low angle side and the peak or shoulder appearing on the high angle side is outside the above-mentioned range. . Calcined hydrotalcite does not have a characteristic peak in the region of 8° to 18°, but has a characteristic peak at 43°. Powder X-ray diffraction measurement was performed using a powder s, the measurement was carried out under the conditions of a diffraction angle range (2θ): 5.0131 to 79.9711°. Peak search is performed using the peak search function of the software attached to the diffraction device, “minimum significance: 0.50, minimum peak chip: 0.01°, maximum peak chip: 1.00°, peak base width: 2.00°, method: second order differentiation. It can be done under the condition of “minimum value of.”

The BET specific surface area of the semi-calcined hydrotalcite is preferably 1 to 250 m2/g, and more preferably 5 to 200 m2/g. The BET specific surface area of semi-calcined hydrotalcite can be calculated by adsorbing nitrogen gas on the surface of the sample using a specific surface area measuring device (Macsorb HM Model 1210 manufactured by Mountex) according to the BET method and using the BET multi-point method. there is.

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

Semi-baked hydrotalcite can be used after surface treatment with a surface treatment agent. As surface treatment agents used for surface treatment, for example, higher fatty acids, alkyl silanes, silane coupling agents, etc. can be used, and among them, higher fatty acids and alkyl silanes are preferable. One type or two or more types of surface treatment agents can be used.

Examples of higher fatty acids include higher fatty acids having 18 carbon atoms or more, such as stearic acid, montanic acid, myristic acid, and palmitic acid, and among these, stearic acid is preferable. These can be used one type or two or more types.

Examples of alkyl silanes include methyltrimethoxysilane, ethyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, octadecyltrimethoxysilane, and dimethyldimethoxysilane. , octyltriethoxysilane, n-octadecyldimethyl(3-(trimethoxysilyl)propyl)ammonium chloride, etc. These can be used one or two or more types.

Silane coupling agents include, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropyl(dimethoxy)methylsilane, and 2-( Epoxy-based silane coupling agents such as 3,4-epoxycyclohexyl)ethyltrimethoxysilane; Mercapto-based silane coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 11-mercaptoundecyltrimethoxysilane; 3-Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethoxymethylsilane, N-phenyl-3-aminopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, Amino silane coupling agents such as N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and N-(2-aminoethyl)-3-aminopropyldimethoxymethylsilane; Uride-based silane coupling agents such as 3-ureide propyltriethoxysilane, vinyl-based silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, and vinylmethyldiethoxysilane; Styryl-based silane coupling agents such as p-styryltrimethoxysilane; Acrylate-based silane coupling agents such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane; Isocyanate-based silane coupling agents such as 3-isocyanate propyltrimethoxysilane, sulfide-based silane coupling agents such as bis(triethoxysilylpropyl)disulfide and bis(triethoxysilylpropyl)tetrasulfide; Phenyltrimethoxysilane, methacryloxypropyltrimethoxysilane, imidazole silane, triazine silane, etc. are mentioned. These can be used one or two or more types.

Surface treatment of semi-calcined hydrotalcite can be performed, for example, by stirring and dispersing untreated semi-calcined hydrotalcite at room temperature with a mixer, adding and spraying a surface treatment agent, and stirring for 5 to 60 minutes. As the mixer, a known mixer can be used, and examples include blenders such as V blenders, ribbon blenders, and bubble cone blenders, mixers such as ball mills, Henschel mixers, and concrete mixers, ball mills, and cutter mills. Additionally, when pulverizing semi-calcined hydrotalcite with a ball mill or the like, the above-mentioned higher fatty acids, alkyl silanes, or silane coupling agents may be added to perform surface treatment. The amount of the surface treatment agent used varies depending on the type of semi-calcined hydrotalcite or the type of surface treatment agent, but is preferably 1 to 10 parts by mass per 100 parts by mass of semi-calcined hydrotalcite that has not been surface treated. In the present invention, surface-treated semi-baked hydrotalcite is also included in “semi-baked hydrotalcite” in the present invention.

The amount of semi-calcined hydrotalcite in the composition of the present invention is not particularly limited as long as the effect of the present invention is exhibited, but is preferably 10 to 70% by mass, and more preferably 25 to 60% by mass, per the entire composition. , 30 to 50% by mass is more preferable. Since semi-baked hydrotalcite has excellent moisture absorption performance, as its amount increases, the moisture barrier properties of the resulting cured product improve. However, if the amount exceeds 70% by mass, problems such as the viscosity of the composition increasing, the adhesion between the composition and the substrate to be sealed due to a decrease in wettability, or the strength of the cured product decreasing and becoming brittle tend to occur. This happens. In addition, since the moisture content in the sealing layer (i.e., cured product) increases due to the interlayer water of the semi-baked hydrotalcite, for example, in the production of an organic EL device, the moisture in the sealing layer causes the light-emitting material (light-emitting layer) to increase. ), there is concern that adverse effects on the electrode layer may become apparent and the occurrence of dark spots in the early stages may increase.

The composition of the present invention may contain uncalcined hydrotalcite as long as the effect of the present invention is not impaired. The amount is preferably 0 to 20% by mass, and more preferably 0, per the entire composition. That is, it is most preferable that the composition of the present invention does not contain uncalcined hydrotalcite. The uncalcined hydrotalcite does not affect the transmittance of the cured product of the composition, but since the water content is large, the moisture barrier property is seen to decrease as the amount increases. For example, if the amount exceeds % by mass, the semi-calcined hydrotalcite As with the site, there are concerns that dark spots in the early stages may increase. The mass ratio of semi-calcined hydrotalcite:microcalcined hydrotalcite is preferably 70:30 to 100:0.

As semi-calcined hydrotalcite, for example, "DHT-4C" (manufactured by Kyowa Chemical Co., Ltd., average particle diameter: 400 nm), "DHT-4A-2" (manufactured by Kyowa Chemical Co., Ltd., average particle diameter) : 400nm), etc. On the other hand, examples of calcined hydrotalcite include "KW-2200" (manufactured by Kyowa Chemical Co., Ltd., average particle diameter: 400 nm), and examples of calcined hydrotalcite include "DHT- 4A” (manufactured by Kyowa Chemical Co., Ltd., average particle diameter: 400 nm).

<Radical polymerization initiator>

The composition of the present invention contains a radical polymerization initiator. There may be only one type of radical polymerization initiator, and two or more types may be used. The radical polymerization initiator may be a photo radical polymerization initiator or a thermal radical polymerization initiator. That is, the radical polymerization initiator is a photo radical polymerization initiator and/or a thermal radical polymerization initiator. The radical polymerization initiator is preferably an optical radical polymerization initiator or a thermal radical polymerization initiator. There may be only one type of radical photopolymerization initiator and the thermal radical polymerization initiator, and two or more types may be used.

Examples of radical photopolymerization initiators include acetophenone, diethoxyacetophenone, 2-[4-(methylthio)methyl-1-phenyl]-2-morpholinopropanone, benzoin, benzoin ethyl ether, Benzylmethylketal, benzophenone, 2-ethylanthraquinone, thioxanthone, diethylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylethoxyphos Pin oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 4-(2-hydroxyethoxy)phenyl (2 -Hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenyl ketone, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-(4-dodecyl Phenyl)-2-hydroxy-2-methylpropan-1-one, 2-methyl-2-morpholino (4-thiomethylphenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-( 4-morpholinophenyl)-butanone, N,N'-octamethylenebisacridine, acryloylbenzophenone, 2-(benzoyloxyimino)-1-[4'-(phenylthio)phenyl]- 1-octanone, 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropane-1- one, 1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2 -methyl-propionyl)-benzyl]phenyl}-2-methylpropan-1-one, phenylglyoxylic acid methyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino Propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholine -4-yl phenyl)-butanone, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(η ⁵ -2,4- Cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium, 1-[4-(phenylthio)phenyl]-1,2- Octanedione 2-(O-benzoyloxime), 1-[6-(2-methylbenzoyl)-9-ethyl-9H-carbazol-3-yl]ethanone O-acetyloxime, etc. are mentioned.

Commercially available radical photopolymerization initiators include, for example, “Omnirad651,” “Omnirad184,” “Omnirad1173,” “Omnirad500,” “Omnirad2959,” “Omnirad127,” “Omnirad754,” “Omnirad907,” manufactured by IGM Resins. Omnirad369", "Omnirad379", "Omnirad819", "OmniradTPO", "Omnirad784", BASF's "Irgacure OXE-01", "Irgacure OXE-02", etc. are mentioned.

Examples of thermal radical polymerization initiators include azo compounds and organic peroxides.

Examples of azo compounds include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(2- Methylbutyronitrile), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-methyl)dihydrochloride, 1,1'-azobis(1-acetoxy- 1-phenylethane), 1,1'-azobis(cyclohexane-1-carbonitrile), dimethyl 2,2'-azobis(isobutyrate), 2,2'-azobis(4-methoxy-2) ,4-dimethylvaleronitrile), 2,2'-azobis(2-methylpropionitrile), 2,2'-azobis(2-methylbutyronitrile), 1-[(1-cyano- 1-methylethyl)azo]formamide, 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile, dimethyl 2,2'-azobis(2-methylpropionate), 2,2 '-Azobis(N-butyl-2-methylpropionamide, etc. are mentioned.

Organic peroxides include, for example, benzoyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, di-tert-butyl peroxide, methyl ethyl ketone peroxide, and 1,1-di(t-hexyl peroxy) cyclo. Hexane, 2,2-di(t-butylperoxy)butane, n-butyl 4,4-di(t-butylperoxy)valate, 2,2-di(4,4-di(t-butylperoxy)valate, Oxy)Cyclohexyl)propane, p-menthane hydroperoxide, diisopropoxylbenzene peroxide, 1,1,3,3-tetramethylbutylhydroperoxide, cumene hydroperoxide, t-butylhydroperoxide, di (2-t-butylperoxyisopropyl)benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-hexyl peroxide Oxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane-3, diisobutyryl peroxide, di(3,5,5-t-methylhexanoyl)peroxide, dilauro Il peroxide, disuccinic acid peroxide, di(3-methylbenzoyl) peroxide, benzoyl peroxide, di-n-propyl peroxycarbonate, di-isopropyl peroxydicarbonate, di(4-t-butylcyclohexyl) Peroxycarbonate, di(2-ethylhexyl)peroxycarbonate, di-sec-butylperoxycarbonate, cumyl peroxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy- 2-ethylhexanoate, 2,5-dimethyl-2,5-di(t-ethylhexanoylperoxy)hexane, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2- Ethylhexanoate, t-hexylperoxyisopropylmonocarbonate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, t-butylperoxyisopropylmonocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butylperoxyacetate, t-butylper Mixture of oxy-3-methylbenzoate and t-butylperoxybenzoate, t-butylperoxybenzoate, t-butylperoxyallyl monocarbonate, 3,3',4,4'-tetra(t-butyl) Peroxycarbol) benzophenone, etc. are mentioned.

Commercially available thermal radical polymerization initiators include, for example, "AIBN" (2,2'-azobis(isobutyronitrile)), manufactured by Wako Pure Chemical Industries, Ltd., and "V-40" (1,1'-azobis(). Cyclohexane-1-carbonitrile), "VAm-110" (2,2'-azobis(N-butyl-2-methylpropionamide), "V-601" (dimethyl2,2'-azobis(iso butyrate), “OTAZO-15” (1,1'-azobis(1-acetoxy-1-phenylethane)), and “MAIB” (dimethyl 2,2'-azobisisobutyrate) manufactured by Otsuka Chemical Co., Ltd. I can hear it.

The amount of the radical polymerization initiator is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and even more preferably 0.5 to 6 parts by mass, based on 100 parts by mass of the “compound having an ethylenically unsaturated group.” Here, the “compound having an ethylenically unsaturated group” includes “polyfunctional ethylenically unsaturated compound” and “monofunctional ethylenically unsaturated compound” as described above.

When using a radical photopolymerization initiator, the amount is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and even more preferably 0.5 parts by mass, based on 100 parts by mass of the “compound having an ethylenically unsaturated group.” to 6 parts by mass.

When using a thermal radical polymerization initiator, the amount is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and still more preferably 0.5 parts by mass, based on 100 parts by mass of the “compound having an ethylenically unsaturated group.” to 6 parts by mass.

<Other ingredients>

The composition of the present invention may contain other components different from the above-mentioned components as long as the effect is not impaired.

The composition of the present invention may contain an epoxy resin for the purpose of suppressing shrinkage of the cured product. There may be only one type of epoxy resin, or two or more types may be used. An epoxy resin having one epoxy group per molecule is sometimes abbreviated as a “monofunctional epoxy resin,” and an epoxy resin having two epoxy groups per molecule is sometimes abbreviated as a “bifunctional epoxy resin.” Epoxy resins having three or more epoxy groups in one molecule are also sometimes abbreviated in the same way.

As described above, a compound having one or more epoxy groups and two or more ethylenically unsaturated groups in one molecule can function as a polyfunctional ethylenically unsaturated compound in the present invention, and therefore, in the present invention, the above-mentioned polyfunctional ethylene It is classified as a sexually unsaturated compound. In addition, as described above, compounds having one or more epoxy groups and one ethylenically unsaturated group in one molecule are classified as monofunctional ethylenically unsaturated compounds in the present invention.

Examples of epoxy resins include hydrogenated epoxy resins (hydrogenated bisphenol A epoxy resins, hydrogenated bisphenol F epoxy resins, etc.), fluorine-containing epoxy resins, linear aliphatic epoxy resins, cyclic aliphatic epoxy resins, and bisphenol A. type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, bisphenol F type epoxy resin, phosphorus-containing epoxy resin, bisphenol S type epoxy resin, aromatic glycidylamine type. Epoxy resins (e.g., tetraglycidyldiaminodiphenylmethane, triglycidyl-p-aminophenol, diglycidyltoluidine, diglycidylaniline, etc.), alicyclic epoxy resin, phenol novolac type epoxy Resin, cresol novolak-type epoxy resin, bisphenol A novolak-type epoxy resin, epoxy resin with butadiene structure, diglycidyl ether of bisphenol, diglycidyl ether of naphthalenediol, diglycidyl ether of phenols. compounds, diglycidyl ethers of alcohols, and alkyl-substituted products of these epoxy resins.

The epoxy equivalent of the epoxy resin is preferably 50 to 1,000, more preferably 50 to 750, further preferably 100 to 750, and particularly preferably 100 to 500 from the viewpoint of reactivity and the like. In addition, “epoxy equivalent weight” is the number of grams (g/eq) of resin containing epoxy groups equivalent to 1 gram, and is measured according to the method specified in JIS K 7236.

The epoxy resin is preferably at least one selected from hydrogenated epoxy resins, fluorine-containing epoxy resins, linear aliphatic epoxy resins, and cyclic aliphatic epoxy resins, and more preferably hydrogenated epoxy resins and fluorine-containing epoxy resins. , and at least one type selected from cyclic aliphatic epoxy resins, and more preferably at least one type selected from hydrogenated epoxy resins and cyclic aliphatic epoxy resins. Here, “hydrogenated epoxy resin” means an epoxy resin obtained by hydrogenating an aromatic ring-containing epoxy resin. The hydrogenation rate of the hydrogenated epoxy resin is preferably 50% or more, and more preferably 70% or more. “Chain aliphatic epoxy resin” means an epoxy resin having a linear or branched alkyl chain or alkyl ether chain, and “cyclic aliphatic epoxy resin” means a cyclic aliphatic skeleton, for example, a cycloalkane skeleton, in the molecule. It means an epoxy resin having .

As the hydrogenated bisphenol A type epoxy resin, for example, liquid hydrogenated bisphenol A type epoxy resin (e.g., “YX8000” (manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: about 205), “Denacol EX-252” ( A solid hydrogenated bisphenol A type epoxy resin (for example, "YX8040" (manufactured by Nagase Chemtex, epoxy equivalent: about 213)) is included.

As the fluorine-containing epoxy resin, for example, the fluorine-containing epoxy resin described in WO2011/089947 can be used.

Examples of linear aliphatic epoxy resins include polyglycerol polyglycidyl ether (e.g., “Denacol EX-512”, “Denacol EX-521”, manufactured by Nagase Chemtex Corporation), and pentaerythritol polyglycidyl. Diglycerol (e.g., “Denacol EX-411”, manufactured by Nagase Chemtex), diglycerol polyglycidyl ether (e.g., “Denacol EX-421”, manufactured by Nagase Chemtex), glycerol Polyglycidyl ether (for example, “Denacol EX-313”, “Denacol EX-314”, manufactured by Nagase Chemtex Corporation), trimethylolpropane polyglycidyl ether (for example, “Denacol EX-314”) -321", manufactured by Nagase Chemtex Corporation), neopentyl glycol diglycidyl ether (e.g., "Denacol EX-211", manufactured by Nagase Chemtex Corporation), 1,6-hexanediol diglycidyl ether (For example, “Denacol EX-212”, manufactured by Nagase Chemtex Co., Ltd.), ethylene glycol diglycidyl ether (for example, “Denacol EX-810”, “Denacol EX-811”, Nagase Chemtex Co., Ltd.) manufactured by Tex Corporation), diethylene glycol diglycidyl ether (e.g. “Denacol EX-850”, “Denacol EX-851” manufactured by Nagase Chemtex Corporation), polyethylene glycol diglycidyl ether (e.g. For example, “Denacol EX-821”, “Denacol EX-830”, “Denacol EX-832”, “Denacol EX-841”, “Denacol EX-861”, manufactured by Nagase Chemtex Corporation), Propylene glycol diglycidyl ether (e.g., “Denacol EX-911”, manufactured by Nagase Chemtex Co., Ltd.), polypropylene glycol diglycidyl ether (e.g., “Denacol EX-941”, “Denacol EX-941”, “Chol EX-920”, “Denacol EX-931”, manufactured by Nagase Chemtex Co., Ltd.), and the like.

Examples of the cyclic aliphatic epoxy resin include "EHPE-3150" manufactured by Daicel Kagakukogyo Co., Ltd.

When an epoxy resin is used, the amount is preferably 5 to 40% by mass, more preferably 5 to 35% by mass, and even more preferably 5 to 30% by mass, per the entire composition.

The composition of the present invention may contain a photocationic polymerization initiator. There may be only one type of photocationic polymerization initiator, and two or more types may be used.

Examples of photocationic polymerization initiators include aromatic sulfonium salts, aromatic iodonium salts, aromatic diazonium salts, aromatic ammonium salts, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe. Salts, etc. can be mentioned.

As aromatic sulfonium salts, for example, bis(4-(diphenylsulfonio)phenyl)sulfide bishexafluorophosphate, bis(4-(diphenylsulfonio)phenyl)sulfide bishexafluoroantimonate. , bis(4-(diphenylsulfonio)phenyl)sulfide bistetrafluoroborate, bis(4-(diphenylsulfonio)phenyl)sulfidetetrakis(pentafluorophenyl)borate, diphenyl-4- (phenylthio)phenylsulfonium hexafluorophosphate, diphenyl-4-(phenylthio)phenylsulfonium hexafluoroantimonate, diphenyl-4-(phenylthio)phenylsulfonium tetrafluoroborate, diphenyl -4-(phenylthio)phenylsulfonium tetrakis(pentafluorophenyl)borate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrafluoroborate Phenylsulfonium tetrakis(pentafluorophenyl)borate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide bishexafluorophosphate, bis(4-(di (4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide bishexafluoroantimonate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio )Phenyl)sulfide bistetrafluoroborate, bis(4-(di(4-2-hydroxyethoxy))phenylsulfonio)phenyl)sulfidetetrakis(pentafluorophenyl)borate, etc.

Examples of aromatic iodonium include diphenyl iodonium hexafluorophosphate, diphenyl iodonium hexafluoroantimonate, diphenyl iodonium tetrafluoroborate, and diphenyl iodonium tetrakis (pentafluorophenyl). Borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis(dodecylphenyl)iodonium hexafluoroantimonate, bis(dodecylphenyl)iodonium tetrafluoroborate, bis(dodecylphenyl)iodine Nium tetrakis(pentafluorophenyl)borate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluorophosphate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoroanti. Monate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrafluoroborate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate, etc. You can.

As aromatic diazonium salts, for example, phenyldiazonium hexafluorophosphate, phenyldiazonium hexafluoroantimonate, phenyldiazonium tetrafluoroborate, phenyldiazonium tetrakis(pentafluorophenyl)borate, etc. I can hear it.

Examples of aromatic ammonium salts include 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, and 1-benzyl-2-cyanopyridinium. Tetrafluoroborate, 1-benzyl-2-cyanopyridinium tetrakis(pentafluorophenyl)borate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluorophosphate, 1-(naphthylmethyl )-2-Cyanopyridinium hexafluoroantimonate, 1-(naphthylmethyl)-2-cyanopyridinium tetrafluoroborate, 1-(naphthylmethyl)-2-cyanopyridinium tetrakis (pentafluorophenyl)borate, etc. can be mentioned.

(2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe salt, for example, (2,4-cyclopentadien-1-yl)((1-methylethyl )Benzene)-Fe(II)hexafluorophosphate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II)hexafluoroantimonate, (2, 4-Cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II)tetrafluoroborate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene )-Fe(II)tetrakis(pentafluorophenyl)borate, etc.

Commercially available photocationic polymerization initiators include, for example, "SP-150", "SP-170", "SP-082", and "SP-103" manufactured by ADEKA, and "CPI-100P" manufactured by San-Apro. Examples include “CPI-101A”, “CPI-200K”, “Omnirad270” manufactured by IGM Resins, and “Omnirad290”.

When using a photo cationic polymerization initiator, the amount is preferably 0.5 to 10 parts by mass based on 100 parts by mass of the total of compounds having an epoxy group (for example, the total of (meth)acrylates and epoxy resins having an epoxy group). parts, more preferably 1.0 to 8 parts by mass, and even more preferably 2.0 to 6 parts by mass.

The composition of the present invention contains a silane coupling agent. There may be only one type of silane coupling agent, or two or more types may be used.

Silane coupling agents include, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropyl(dimethoxy)methylsilane, and 2-( Epoxy-based silane coupling agents such as 3,4-epoxycyclohexyl)ethyltrimethoxysilane; Mercapto-based silane coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 11-mercaptoundecyltrimethoxysilane; 3-Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethoxymethylsilane, N-phenyl-3-aminopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, Amino silane coupling agents such as N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and N-(2-aminoethyl)-3-aminopropyldimethoxymethylsilane; Uride-based silane coupling agents such as 3-ureide propyltriethoxysilane; Vinyl-based silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, and vinylmethyldiethoxysilane; Styryl-based silane coupling agents such as p-styryltrimethoxysilane; Acrylate-based silane coupling agents such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane; Isocyanate-based silane coupling agents such as 3-isocyanate propyltrimethoxysilane; Sulfide-based silane coupling agents such as bis(triethoxysilylpropyl)disulfide and bis(triethoxysilylpropyl)tetrasulfide; Phenyltrimethoxysilane, methacryloxypropyltrimethoxysilane, imidazole silane, triazine silane, etc. are mentioned. Among these, acrylate-based silane coupling agents are preferable.

Commercially available silane coupling agents include, for example, "KBM-502", "KBM-503", "KBE-502", "KBE-503", "KBM-5103", and "KBM-5803" manufactured by Shin-Etsu Chemical Co., Ltd. You can lift your back.

When using a silane coupling agent, the amount is preferably 0.10 to 5.00% by mass, more preferably 0.25 to 3.00% by mass, and even more preferably 0.30 to 2.00% by mass, per the entire composition.

The composition of the present invention may contain a polymerization inhibitor. There may be only one type of polymerization inhibitor, and two or more types may be used.

Examples of polymerization inhibitors include t-butylhydroquinone, p-benzoquinone, hydroquinone, p-methoxyphenol, N,N-diethylhydroxylamine, and N-nitroso-N-phenylhydroxylamine. Ammonium salts, etc. can be mentioned. Commercially available products containing polymerization inhibitors include, for example, "Q-1301", "TBHQ", "PBQ2", "DEHA", and "MEHQ" manufactured by Wako Pure Chemical Industries, Ltd., and "QS-10" manufactured by Kawasaki Kaseiko Chemical Industries, Ltd. I can hear it.

When a polymerization inhibitor is used, the amount is preferably 10 to 200 ppm, more preferably 50 to 100 ppm, based on 100 parts by mass of the “compound having an ethylenically unsaturated group.” In addition, the above “ppm” is based on mass. Here, the “compound having an ethylenically unsaturated group” includes “polyfunctional ethylenically unsaturated compound” and “monofunctional ethylenically unsaturated compound” as described above.

<Total light transmittance of the cured material layer>

The total light transmittance of the cured layer (thickness: 20 μm) of the composition of the present invention to D65 light is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more.

The total light transmittance of the cured material layer to D65 light is calculated by forming a laminate with the cured product of the composition sandwiched between glass plates and using air as a reference, as described in the Examples described later. In addition, the value of the total light transmittance to D65 light mentioned above is a measurement value of a cured layer having a thickness of 20 μm, but the thickness of the cured layer is generally 3 to 200 μm.

<Haze of hardened layer>

The haze of the cured layer (thickness: 20 μm) of the composition of the present invention is preferably less than 3.0%.

The haze of the cured layer is calculated by forming a laminate in which the cured product of the composition is sandwiched between glass plates and using air as a reference, as described in the Examples described later. In addition, the above-mentioned haze value is a measurement value of a cured material layer with a thickness of 20 μm, but the thickness of the cured material layer is generally 3 to 200 μm.

A cured layer with a total light transmittance of 85% or more and a haze of less than 3.0% can be recognized as transparent with the naked eye.

<Organic EL device>

An organic EL device in which an organic EL element is sealed with a cured product of the composition of the present invention can be manufactured, for example, by applying the composition of the present invention on an organic EL element on a substrate and then curing the composition.

When the composition of the present invention contains a radical photopolymerization initiator, curing can be performed by irradiating the composition with ultraviolet rays. Examples of devices for ultraviolet irradiation include high-pressure mercury lamps, ultra-high pressure mercury lamps, metal halide lamps, high-power metal halide lamps, low-pressure mercury lamps, and LED light sources. The temperature of the composition when irradiated with ultraviolet rays is preferably 20 to 120°C, more preferably 25 to 110°C. The cumulative irradiation amount of ultraviolet rays is preferably 500 to 4000 mJ/cm2, more preferably 1000 to 3500 mJ/cm2.

When the composition of the present invention contains a thermal radical polymerization initiator, curing can be performed by heating the composition using a dryer or the like. The heating temperature is preferably 80 to 120°C, more preferably 100 to 110°C, and the heating time is preferably 15 to 120 minutes, more preferably 30 to 90 minutes. This heating may be performed under an atmospheric atmosphere or an inert gas (for example, nitrogen gas) atmosphere.

Example

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited by the following examples, and may of course be implemented with appropriate changes within the scope suitable for the above and below purposes. It is possible, and they are all included in the technical scope of the present invention.

In addition, “part” in the amount described below and “%” in the saturated water absorption and thermal weight reduction rate mean “part by mass” and “% by mass”, respectively, unless otherwise specified. In addition, “room temperature” means 20 to 30°C.

The viscosity of the monofunctional acrylate (“Light Acrylate IB-XA” manufactured by Kyoeisha Chemical Co., Ltd.) used as a diluent in the following examples and comparative examples was measured with a type B viscometer under a temperature condition of 25°C. As a result, the viscosity was 10 mPa·s.

<Example 1>

20 parts of hexafunctional acrylate (“KAYARAD DPCA-60” manufactured by Nippon Kayaku Co., Ltd.), 100 parts of bifunctional acrylate (“IRR214-K” manufactured by Daicel Ornex Co., Ltd.) having an alicyclic skeleton, and bifunctional acrylate 50 parts of (bisphenol A type epoxy acrylate, “EBECRYL600” manufactured by Daicel Ornex), 2 parts of silane coupling agent (“KBM-5103” manufactured by Shin-Etsu Silicone), and commercially available semi-calcined hydrotalcite (BET ratio) After kneading 96 parts (surface area: 15 m2/g, average particle diameter: 400 nm), dispersion was performed using a three-roll mill to obtain a mixture. Next, 50 parts of a monofunctional acrylate having an alicyclic skeleton (“Light Acrylate IB-XA” manufactured by Kyoeisha Chemical Co., Ltd.) (diluent) and a bifunctional acrylate (“Light Acrylate” manufactured by Kyoeisha Chemical Co., Ltd.) were added to the obtained mixture. 50 parts of "Rate NP-A" (which also functions as a diluent) and 2 parts of a thermal radical polymerization initiator ("V-601" manufactured by Wako Pure Chemical Industries, Ltd.) were mixed and uniformly dispersed with a high-speed rotating mixer to obtain a composition.

<Example 2>

A composition was obtained in the same manner as in Example 1, except that the amount of semi-calcined hydrotalcite was changed to 170 parts.

<Example 3>

20 parts of hexafunctional acrylate (“KAYARAD DPCA-60” manufactured by Nippon Kayaku Co., Ltd.), 80 parts of bifunctional acrylate (“IRR214-K” manufactured by Daicel Ornex Co., Ltd.) having an alicyclic skeleton, and UVACURE1561 (Daicel Manufactured by Ornex, 20 parts of a mixture of a compound having an epoxy group and one acryloyl group per molecule (content: 78 to 82%) and bisphenol A type epoxy resin (content: 18 to 22%), and addition of liquid hydrogen. 30 parts of bisphenol A type epoxy resin (“YX8000” manufactured by Mitsubishi Chemical Corporation), 2 parts of silane coupling agent (“KBM-5103” manufactured by Shin-Etsu Silicone Corporation), and commercially available semi-baked hydrotalcite (BET specific surface area: 15 m2) /g, average particle diameter: 400 nm) After kneading 150 parts, dispersion was performed using a three-roll mill to obtain a mixture. Next, 100 parts of a monofunctional acrylate having an alicyclic skeleton (“Light Acrylate IB-XA” manufactured by Kyoeisha Chemical Co., Ltd.) and a thermal radical polymerization initiator (“V-601” manufactured by Wako Pure Chemical Industries, Ltd.) were added to the obtained mixture. ) were mixed and uniformly dispersed with a high-speed rotating mixer to obtain a composition.

<Example 4>

The composition was prepared in the same manner as in Example 3 except that the amount of semi-calcined hydrotalcite was changed to 96 parts and the thermal radical polymerization initiator was changed to 2 parts to 2 parts photo radical polymerization initiator (“Omnirad OXE-01” manufactured by BASF). got it

<Example 5>

A composition was obtained in the same manner as in Example 4 except that 2 parts of a photocationic polymerization initiator (“SP-152” manufactured by ADEKA) was additionally added.

<Comparative Example 1>

A composition was obtained in the same manner as in Example 1, except that 96 parts of semi-calcined hydrotalcite were replaced with 96 parts of magnesium oxide (BET specific surface area: 8.9 m2/g, average particle diameter: 500 nm).

<Comparative Example 2>

100 parts of a bifunctional epoxy resin having an alicyclic skeleton (“EP4088SS” manufactured by Adeka Corporation), 20 parts of a tetrafunctional epoxy resin (“jER604” manufactured by Mitsubishi Chemical Corporation), and 20 parts of a bifunctional epoxy resin (manufactured by Shinnittetsu Sumikinkaku Corporation) 100 parts of “ZX-1059”), 2 parts of silane coupling agent (“KBM-403” manufactured by Shin-Etsu Silicone Co., Ltd.), and commercially available semi-calcined hydrotalcite (BET specific surface area: 15 m2/g, average particle diameter: 400 nm) ) After kneading 96 parts, dispersion was performed using a three-roll mill to obtain a mixture. Next, 50 parts of a monofunctional epoxy resin (“EX-121” manufactured by Nagase Chemtex Co., Ltd.) and 2 parts of a thermal anionic polymerization initiator (“TBPDA” manufactured by Hokko Chemical Co., Ltd.) were added to the obtained mixture, and the mixture was uniformly mixed with a high-speed rotating mixer. By dispersing, a composition was obtained.

<Absorption rate of hydrotalcite>

The initial mass of the hydrotalcite used in the examples and comparative examples was measured by weighing 1.5 g on a balance. It was left standing in a small environmental tester (SH-222 manufactured by Espec) set at 60°C and 90%RH (relative humidity) under atmospheric pressure for 200 hours, the mass after moisture absorption was measured, and the saturated water absorption rate was determined using the formula (i) above. saved. The results are shown in Table 1.

<Thermal weight reduction rate of hydrotalcite>

Thermogravimetric analysis of the hydrotalcite used in the examples and comparative examples was performed using TG/DTA EXSTAR6300 manufactured by Hitachi High-Tech Science. 10 mg of hydrotalcite was weighed in an aluminum sample pan, and the temperature was raised from 30°C to 550°C at 10°C/min in an atmosphere with a nitrogen flow rate of 200 mL/min in an open state without covering the lid. Using equation (ii) above, the thermal weight reduction rate at 280°C and 380°C was obtained. The results are shown in Table 1.

<Powder X-ray diffraction>

Powder X-ray diffraction was measured using a powder /s, the measurement diffraction angle range (2θ) was performed under the conditions of 5.0131 to 79.9711°. The peak search is performed using the peak search function of the software attached to the diffraction device, “minimum significance: 0.50, minimum peak chip: 0.01°, maximum peak chip: 1.00°, peak base width: 2.00°, method: second order differentiation. This was carried out under the conditions of “minimum value.” A peak with a shoulder is detected by combining two split peaks or two peaks that appear within the range of 2θ from 8 to 18°, and the diffraction intensity of the peak or shoulder appearing on the low angle side (=low angle side) Diffraction intensity) and the diffraction intensity of the peak or shoulder appearing on the high-angle side (=high-angle side diffraction intensity) were measured, and the relative intensity ratio (=low-angle side diffraction intensity/high-angle side diffraction intensity) was calculated. The results are shown in Table 1.

[Table 1]

From the results of saturated water absorption, thermal weight reduction, and powder X-ray diffraction, it was confirmed that the hydrotalcite used in the examples and comparative examples was “semi-calcined hydrotalcite.”

<Total light transmittance and haze of the cured layer of the composition>

The composition prepared in the examples and comparative examples was dropped onto an alkali-free glass plate (length 50 mm, width 50 mm, thickness 700 μm, OA-10G manufactured by Nippon Denki Karasu), and then alkali-free glass plates of the same size were overlapped to form a laminate (alkali-free). A glass plate/resin composition layer/alkali-free glass plate) was prepared. Next, in Examples 1 to 3 and Comparative Examples 1 and 2, the composition was cured by heating the laminate at 100°C for 30 minutes to produce an evaluation sample (thickness of the cured product: 20 μm). Additionally, in Examples 4 and 5, evaluation was conducted by curing the composition by irradiating ultraviolet rays to the laminate at room temperature using a UV-LED (manufactured by Ushiosa, wavelength 365 nm) until the cumulative irradiation amount reached 3,000 mJ/cm2. A sample (thickness of cured product: 20 μm) was produced.

Using a haze meter HZ-V3 (halogen lamp) manufactured by Suga Shikenki Co., Ltd., the total light transmittance and haze of the evaluation sample were measured with D65 light using air as a reference, and evaluated based on the following criteria. The results are shown in Table 2.

(Standard for total light transmittance)

Good (○): 90% or more

Possible (△): Less than 90%, more than 85%

Defective (×): Less than 85%

(Hayes' standard)

Good (○): Less than 2.5%

Possible (△): 2.5% or more, less than 3.0%

Defective (×): 3.0% or more

<Device reliability test (remaining light emission area ratio)>

The sealing properties of the composition were evaluated using an organic EL device. In detail, first, an organic EL device (thickness of organic film: 110 nm, thickness of Al cathode: 100 nm) was formed on an indium tin oxide (ITO)-coated glass substrate (manufactured by Diomatech) with an emission area of 4 mm2. Next, a nitride film (thickness: 500 nm) was formed on the organic EL device using a chemical vapor deposition method (CVD method).

Next, the composition prepared in Example 2-5 was dropped onto an organic EL device with a nitride film, and then an alkali-free glass plate was placed on top of it to form a laminate (alkali-free glass plate/composition layer/organic EL device with a nitride film/glass with ITO). substrate) was prepared. In Examples 2 and 3, the laminate was heated at 100°C for 30 minutes to cure the composition, thereby producing a laminate sealing the organic EL element (thickness of the cured product: 100 μm). In Examples 4 and 5, the composition was cured by irradiating the laminate with ultraviolet rays at room temperature using a UV-LED (manufactured by Ushio, 365 nm) until the cumulative irradiation amount reached 3,000 mJ/cm2, thereby producing an organic EL device. A sealed laminate was manufactured (thickness of the cured product: 100 μm).

Voltage was applied to the sealed organic EL device, and the initial emission area was measured before storage in a constant temperature and humidity bath. Next, the laminate in which the organic EL device was sealed was stored in a constant temperature and humidity bath set at a temperature of 85°C and a humidity of 85%RH. After 1000 hours of storage, the laminate was taken out of the constant temperature and humidity bath, voltage was applied to the organic EL element, and the light emitting area after storage was measured.

As an index for comparing the barrier properties of the sealing layer (cured product), the remaining luminous area ratio is expressed by the following equation:

Remaining light emitting area ratio (%) = 100 × (light emitting area after storage) / (initial light emitting area)

It was calculated from and evaluated based on the following standards. The results are shown in Table 2.

(Standard for remaining luminous area ratio)

Very good (◎): 95% or more

Good (○): 85% or more but less than 95%

Possible (△): 75% or more but less than 85%

Defective (×): Less than 75%

[Table 2]

According to the sealing composition of the present invention, a sealing layer excellent in both moisture barrier properties and transparency can be formed. Therefore, the sealing composition of the present invention can be suitably used for sealing devices that are vulnerable to moisture, such as organic EL devices.

This application is based on Japanese Patent Application No. 2017-071985, the contents of which are entirely included in the specification of this application.

Claims (16)

A sealing composition containing a compound having two or more ethylenically unsaturated groups in one molecule, a semi-baked hydrotalcite, and a radical polymerization initiator, and having fluidity at 25°C and 1 atm. The composition according to claim 1, wherein the compound having two or more ethylenically unsaturated groups in one molecule includes a compound having three or more ethylenically unsaturated groups in one molecule. The composition according to claim 1 or 2, wherein the compound having two or more ethylenically unsaturated groups in one molecule contains a compound having two or more ethylenically unsaturated groups and an alicyclic structure in one molecule. The composition according to claim 1 or 2, further comprising a reactive diluent having one ethylenically unsaturated group per molecule. The composition according to claim 1 or 2, which does not contain a solvent. The composition according to claim 1 or 2, wherein the ethylenically unsaturated group is a (meth)acryloyl group. The composition according to claim 1 or 2, wherein the amount of the compound having two or more ethylenically unsaturated groups per molecule is 20 to 78% by mass per molecule. The composition according to claim 1 or 2, wherein the amount of semi-calcined hydrotalcite is 10 to 70% by mass per total composition. The composition according to claim 1 or 2, wherein the radical polymerization initiator is an optical radical polymerization initiator and/or a thermal radical polymerization initiator. The composition according to claim 1 or 2, wherein the amount of the radical polymerization initiator is 0.5 to 10 parts by mass based on 100 parts by mass of the compound having an ethylenically unsaturated group. The composition according to claim 1 or 2, further comprising a silane coupling agent. The composition according to claim 1 or 2, wherein the total light transmittance to D65 light of the cured layer of the composition having a thickness of 20 μm is 85% or more. The composition according to claim 1 or 2, wherein the haze of the cured layer of the composition having a thickness of 20 μm is less than 3.0%. The composition according to claim 1 or 2, which is used for sealing an organic EL device. An organic EL device in which an organic EL element is sealed with a cured product of the composition according to claim 1 or 2. delete