阅读说明：本技术 密封用树脂组合物、密封片和有机el元件密封结构体 (Sealing resin composition, sealing sheet, and organic EL element sealing structure ) 是由 宇野荣二 耿志亮 细谷哲也 于 2020-03-25 设计创作，主要内容包括：本发明提供能够得到平衡良好地发挥低透湿性、与被粘物的密合性和高温高湿下的粘接可靠性的密封片(密封材料)的密封用树脂组合物。本发明的一个实施方式为密封用树脂组合物。该密封用树脂组合物含有改性聚烯烃树脂和有机金属化合物。在该密封用树脂组合物中,相对于上述改性聚烯烃树脂100质量份,上述有机金属化合物的配合量为0.1～10质量份。(The present invention provides a sealing resin composition which can obtain a sealing sheet (sealing material) which has well-balanced low moisture permeability, adhesion to an adherend, and adhesion reliability under high temperature and high humidity. One embodiment of the present invention is a resin composition for sealing. The sealing resin composition contains a modified polyolefin resin and an organometallic compound. In the resin composition for sealing, the amount of the organic metal compound is 0.1 to 10 parts by mass per 100 parts by mass of the modified polyolefin resin.)

1. A resin composition for sealing, comprising a modified polyolefin resin and an organometallic compound,

the amount of the organometallic compound is 0.1 to 10 parts by mass per 100 parts by mass of the modified polyolefin resin.

2. The sealing resin composition according to claim 1, wherein the modified polyolefin resin has a weight average molecular weight of 5 to 80 ten thousand.

3. The sealing resin composition according to claim 1 or 2, wherein the modified polyolefin resin has an acidic functional group.

4. The sealing resin composition according to claim 3, wherein the organometallic compound has 1 or more substituents selected from an alkoxy group and an alkylacetoacetate group.

5. The sealing resin composition according to any one of claims 1 to 4, wherein the organometallic compound is an organoaluminum compound.

6. The sealing resin composition according to claim 5, wherein the organoaluminum compound is at least 1 selected from the group consisting of aluminum tris (acetylacetonate), aluminum tris (ethylacetoacetate), aluminum monoacetylacetonate bis (ethylacetoacetate), ethylacetoacetate diisopropoxyaluminum, and aluminum isopropoxide.

7. The sealing resin composition according to any one of claims 1 to 6, further comprising 1 or more tackifier resins selected from terpene resins and petroleum resins.

8. A sealing sheet comprising a sealing layer at least a part of which is made of the sealing resin composition according to any one of claims 1 to 7.

9. An organic EL element sealing structure comprising an organic EL layer and a sealing layer for sealing the organic EL layer, wherein the sealing layer is formed from the sealing sheet according to claim 8.

Technical Field

The present invention relates to a sealing resin composition, a sealing sheet, and an organic EL element sealing structure.

Background

In recent years, organic EL displays have been attracting attention as displays replacing Liquid Crystal Displays (LCDs).

In general, it is known that an organic EL element used in an organic EL display is deteriorated by moisture, and as the organic EL element is deteriorated, there is a problem that light emission characteristics such as light emission luminance, light emission efficiency, and light emission uniformity are deteriorated.

Therefore, in order to prevent the intrusion of external moisture or the like, a technique of sealing an organic EL element with a sealing material having low moisture permeability is known (patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2017-101145

Disclosure of Invention

Problems to be solved by the invention

In recent years, the frame of an organic EL display has been narrowed and flexibility has been studied, and a sealing material for sealing an organic EL element is required to have not only low moisture permeability but also high adhesion to an adherend (glass) so that defects such as peeling do not occur when a laminated substrate is bent. Further, it is also required to stably exhibit high adhesion reliability for a long period of time even under a severe environment such as high temperature and high humidity.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a sealing resin composition which can provide a sealing sheet (sealing material) that exhibits adhesion reliability under high temperature and high humidity stably for a long period of time, in addition to low moisture permeability and adhesion to an adherend.

Means for solving the problems

One embodiment of the present invention is a resin composition for sealing. The resin composition for sealing comprises a modified polyolefin resin and an organic metal compound, wherein the amount of the organic metal compound is 0.1-10 parts by mass per 100 parts by mass of the modified polyolefin resin.

Another embodiment of the invention is a sealing sheet. At least a part of the sealing sheet is formed of a cured product of the sealing resin composition of the above-described embodiment.

Still another embodiment of the present invention is an organic EL element sealing structure. The organic EL element sealing structure includes an organic EL layer and a sealing layer for sealing the organic EL layer, and the sealing layer is formed of the sealing sheet of the above aspect.

Effects of the invention

According to the present invention, a sealing resin composition capable of providing a sealing sheet (sealing material) that exhibits adhesion reliability under high temperature and high humidity stably for a long period of time in addition to low moisture permeability and adhesion to an adherend can be provided.

Drawings

Fig. 1 is a schematic cross-sectional view of an organic EL element of an embodiment.

Fig. 2 is a diagram showing an outline of measurement of holding force applied to the seal sheet.

Fig. 3 is a diagram showing an outline of a constant load test performed on the seal piece.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail. In the present specification, the expression "a to b" in the description of the numerical range means a to b unless otherwise specified.

The sealing resin composition according to the embodiment contains a modified polyolefin resin and an organometallic compound. Hereinafter, each component of the sealing resin composition of the present embodiment will be described in detail.

(modified polyolefin resin)

The modified polyolefin resin can be obtained by modifying an unmodified polyolefin resin as a precursor with a compound having an acidic functional group. In the present embodiment, by using the modified polyolefin resin, low moisture permeability and adhesion to an adherend can be achieved at a higher level.

The unmodified polyolefin resin refers to an α -olefin such as ethylene, propylene, 1-butene, 1-hexene, 1-heptene, 1-octene, 1-decene, isobutylene, 3-methyl-1-butene, 4-methyl-1-pentene, etc.; homopolymers of conjugated dienes such as 1, 3-butadiene, isoprene, 2, 3-dimethyl-1, 3-butadiene, 1, 3-pentadiene, 2-methyl-1, 3-pentadiene, 1, 3-hexadiene, 4, 5-diethyl-1, 3-octadiene and chloroprene, copolymers of these two or more monomers such as random, block and graft, mixtures thereof, and copolymers of a main portion of an α -olefin and/or conjugated diene with other unsaturated monomers such as random, block and graft.

Among these, the non-modified polyolefin resin as a precursor is preferably a polyisobutylene polymer or an isobutylene-isoprene copolymer from the viewpoint of making the low moisture permeability higher.

Commercially available polyisobutylene polymers include OPPANOL N50, OPPANOL N80, OPPANOL N100, OPPANOL B50, OPPANOL B80, OPPANOL B100 (manufactured by BASF Japan), and the like. Further, examples of commercially available isobutylene-isoprene copolymers include JSR BUTYL 065, JSR BUTYL268, and JSR BUTYL 365 (manufactured by JSR).

Examples of the compound having an acidic functional group include maleic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, phthalic anhydride, maleic anhydride, acrylic acid, and methacrylic acid.

The modified polyolefin resin is obtained by reacting the above-mentioned unmodified polyolefin resin with a compound having an acidic functional group. The amount of the compound having an acidic functional group which reacts with the unmodified polyolefin resin is preferably 0.05 to 8 parts by mass, more preferably 0.1 to 5 parts by mass, and still more preferably 0.5 to 3 parts by mass, relative to 100 parts by mass of the unmodified polyolefin resin.

The sealing resin composition of the present embodiment may contain an unreacted unmodified polyolefin resin remaining in the process of modifying the unmodified polyolefin resin. In the sealing resin composition of the present embodiment, the content of the unmodified polyolefin resin relative to the total amount of the unmodified polyolefin resin and the modified polyolefin resin is preferably 90 mass% or more, and more preferably 95 mass% or more, from the viewpoint of stably exhibiting adhesion reliability under high temperature and high humidity for a long period of time.

The lower limit of the weight average molecular weight of the modified polyolefin resin is preferably 5 ten thousand or more, and more preferably 8 ten thousand or more. When the lower limit of the weight average molecular weight of the modified polyolefin resin is set to the above value, the occurrence of foaming and lifting can be suppressed for a longer period of time when the sealing sheet obtained from the sealing resin composition is adhered to an adherend, and the durability can be improved.

The upper limit of the weight average molecular weight of the modified polyolefin resin is preferably 80 ten thousand or less, more preferably 60 ten thousand or less, and further preferably 45 ten thousand or less. When the upper limit of the weight average molecular weight of the modified polyolefin resin is set to the above value, the viscosity of the sealing resin composition can be suppressed from becoming excessively high, and the processability of the sealing resin composition can be favorably maintained.

Here, the weight average molecular weight is a value determined by using Gel Permeation Chromatography (GPC) in terms of polystyrene.

(Process for producing modified polyolefin resin)

The modified polyolefin resin can be produced by a known method, but is preferably produced by solution polymerization. Specifically, an unmodified polyolefin resin, a compound having an acidic functional group, and a polymerization solvent are added to a reaction vessel, a polymerization initiator is added in an inert gas atmosphere such as nitrogen, and the mixture is heated to a reaction temperature of about 50 to 90 ℃ and reacted for 2 to 20 hours. In the polymerization reaction, a polymerization initiator, a chain transfer agent, a compound having an acidic functional group, and a polymerization solvent may be added as appropriate.

Examples of the polymerization initiator include common organic polymerization initiators such as peroxides and azo compounds, and among them, peroxides are preferred.

Examples of the peroxides include 1, 1, 3, 3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-hexyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxy-2-ethylhexanoate, cumyl peroxyneodecanoate, 1, 3, 3-tetramethylbutyl peroxyneodecanoate, tert-hexyl peroxyneodecanoate, tert-butyl peroxyneoheptanoate, tert-hexyl peroxypivalate, tert-butyl peroxypivalate, 2, 5-dimethyl-2, 5-di (2-ethylhexanoylperoxy) hexane, 2, 5-dimethyl-2, 5-di (2-benzoylperoxy) hexane, tert-butylperoxy-3, 5, 5-trimethylhexanoate, tert-butylperoxylauryl peroxide, tert-hexyl peroxybenzoate, Benzoyl peroxide.

The polymerization initiator may be used alone in 1 kind, or may be used in 2 or more kinds.

The amount of the polymerization initiator used is usually 0.01 to 5 parts by mass per 100 parts by mass of the unmodified polyolefin resin. In this manner, the weight average molecular weight of the modified polyolefin resin can be adjusted to an appropriate range.

In the solution polymerization, examples of the polymerization solvent include aromatic hydrocarbons such as benzene, toluene, xylene, etc.; aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane; ethers such as diethyl ether, diisopropyl ether, 1, 2-dimethoxyethane, dibutyl ether, tetrahydrofuran, dioxane, anisole, phenetole, and diphenyl ether; halogenated hydrocarbons such as chloroform, carbon tetrachloride, 1, 2-dichloroethane, chlorobenzene, and the like; esters such as ethyl acetate, propyl acetate, butyl acetate, and methyl propionate; ketones such as acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, and cyclohexanone; amides such as N, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone; nitriles such as acetonitrile and benzonitrile; sulfoxides such as dimethyl sulfoxide and sulfolane. The polymerization solvent may be used alone in 1 kind, or may be used in 2 or more kinds.

(organometallic Compound)

The sealing resin composition according to the embodiment contains the organometallic compound, and the modified polyolefin resin forms a crosslinked structure, thereby further improving the cohesive force.

The organic metal compound includes an organic aluminum compound, an organic zirconium compound, and an organic titanium compound, and the organic metal compound may be used alone in 1 kind, or may be used in 2 or more kinds.

Among the above-mentioned organometallic compounds, an organoaluminum compound can be preferably used from the viewpoint of good compatibility with the modified polyolefin resin.

The organoaluminum compound preferably has 1 or more substituents selected from an alkoxy group and an alkyl acetoacetate group. The adhesion of the sealing layer (pressure-sensitive adhesive layer) obtained from the sealing resin composition to an adherend is improved by providing the organoaluminum compound with 1 or more substituents selected from an alkoxy group and an alkyl acetoacetate group.

More specifically, the organoaluminum compound includes 1 or more selected from the group consisting of tris (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, aluminum bis (ethylacetoacetate) monoacetylacetonate, ethylacetoacetate diisopropoxyaluminum, and isopropylaluminum oxide.

Among the organic aluminum compounds, ethyl acetoacetate diisopropoxyaluminum and isopropylaluminum oxide are preferably used from the viewpoint of improving the permeability of the sealing layer (pressure-sensitive adhesive layer) obtained from the sealing resin composition.

In the sealing resin composition of the present embodiment, the lower limit of the amount of the organometallic compound to be blended is preferably 0.1 part by mass or more, more preferably 0.2 part by mass or more, and still more preferably 0.3 part by mass or more, per 100 parts by mass of the modified polyolefin resin. When the lower limit of the amount of the organometallic compound is set to the above value, the adhesive strength of the sealing layer (adhesive layer) obtained from the sealing resin composition can be practically sufficient.

On the other hand, the upper limit of the amount of the organometallic compound to be blended is preferably 10 parts by mass or less, more preferably 9 parts by mass or less, and still more preferably 7 parts by mass or less, with respect to 100 parts by mass of the modified polyolefin resin. When the upper limit of the amount of the organic metal compound is set to the above value, the compatibility with the modified polyolefin resin can be improved, and the smoothness of the coating film can be maintained when the sealing resin composition is formed into a sealing layer (pressure-sensitive adhesive layer).

(tackifying resin)

A tackifier resin may be added to the sealing resin composition of the present embodiment. By adding a tackifier resin to the sealing resin composition of the present embodiment, the adhesive strength of the obtained sealing layer (adhesive layer) can be further improved.

The tackifier resin may be at least 1 selected from the group consisting of terpene resins and petroleum resins.

Examples of the terpene resin include modified terpene resins such as terpene resins, hydrogenated terpene resins, terpene-phenol copolymer resins, and aromatic modified terpene resins.

Examples of the petroleum resin include aliphatic petroleum resins (C5-based petroleum resins), aromatic petroleum resins (C9-based petroleum resins), alicyclic petroleum resins such as dicyclopentadiene-based petroleum resins (DCPD-based petroleum resins), aliphatic/aromatic copolymer petroleum resins, alicyclic/aromatic copolymer petroleum resins, aliphatic/alicyclic copolymer petroleum resins, and hydrogenated petroleum resins obtained by hydrogenating the above-mentioned petroleum resins.

In the present embodiment, the softening point of the tackifier resin in the sealing resin composition is preferably 80 to 180 ℃, more preferably 90 to 150 ℃, and even more preferably 95 to 140 ℃ from the viewpoint of the durability and adhesive properties of the obtained sealing layer (adhesive layer).

The amount of the tackifier resin to be blended in the sealing resin composition of the present embodiment is preferably 5 to 50 parts by mass, more preferably 10 to 35 parts by mass, and even more preferably 15 to 30 parts by mass, per 100 parts by mass of the modified polyolefin resin, from the viewpoint of not impairing the low moisture permeability and improving the adhesive strength of the sealing layer (adhesive layer) obtained from the sealing resin composition.

(other Components)

The sealing resin composition of the present embodiment may contain a curing agent, an antioxidant, a wettability improver, a surfactant, a silane coupling agent, an ultraviolet absorber, an antistatic agent, a light stabilizer, a filler, a pigment, and the like as necessary within a range not to impair the object of the present invention.

The sealing resin composition of the present embodiment preferably contains an organic solvent in order to adjust its coatability. The organic solvent includes the polymerization solvents described in the description of the method for producing the modified polyolefin resin, and 1 kind or 2 or more kinds may be used alone.

In the sealing resin composition of the present embodiment, the content of the organic solvent is usually 20 to 90% by mass, preferably 30 to 90% by mass.

The sealing resin composition of the present embodiment can be obtained by mixing the above components, and stirring them at a temperature of 20 to 80 ℃ using a stirrer or the like to sufficiently disperse the components.

The sealing resin composition described above exhibits a low moisture permeability, adhesion to an adherend, and adhesion reliability under high temperature and high humidity in a balanced manner. Therefore, the sealing resin composition of the present embodiment can be suitably used as a sealing material for an organic EL device.

(sealing fin)

At least a part of the sealing sheet of the embodiment is formed of a cured product of the sealing resin composition of the above embodiment.

The sealing sheet of the present embodiment may be a single-layer pressure-sensitive adhesive layer composed of a sealing layer obtained from a sealing resin composition, or may have a multilayer structure composed of a pressure-sensitive adhesive layer composed of a sealing layer obtained from a sealing resin composition and another layer laminated on the pressure-sensitive adhesive layer. Examples of the other layer to be laminated with the pressure-sensitive adhesive layer include a release sheet such as a PET film subjected to a release treatment, a substrate, a barrier film, and the like.

The sealing sheet may have a sealing layer formed on one surface or both surfaces of the base material. When the sealing layer is formed on one surface of the substrate, a release sheet may be attached to the surface of the sealing layer opposite to the substrate.

The sealing sheet may have a sealing layer formed on one or both surfaces of the barrier film. When the seal layer is formed on one surface of the barrier film, a release sheet may be attached to the surface of the seal layer opposite to the barrier film.

The sealing layer of the present embodiment is formed, for example, as follows. The sealing resin composition of the present invention is applied to the release-treated surface of a release sheet, or to a substrate, or to a gas barrier film, and dried at 50 to 150 ℃, preferably 60 to 130 ℃, for 1 to 10 minutes, preferably 2 to 7 minutes, depending on the type of solvent, and the solvent is removed to form a coating film. The thickness of the dried coating film is not particularly limited, and can be adjusted depending on the object to be sealed, and is usually 0.5 to 200. mu.m.

After the sealing sheet is attached to the release sheet on the coating film formed under the above conditions, the sealing sheet is cured (cured) in an environment of usually 3 days or more, preferably 7 to 10 days, usually 5 to 60 ℃, preferably 15 to 40 ℃, usually 30 to 70% RH, preferably 40 to 70% RH.

As a method for applying the sealing resin composition, a method of applying and drying the resin composition to a predetermined thickness by a known method, for example, a known application method such as a spin coating method, a doctor blade coating method, a roll coating method, a bar coating method, a blade coating method, a die coating method, a gravure coating method, or the like, can be used.

Examples of the substrate and the release sheet include plastic films such as Polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), Polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, acrylonitrile-butadiene-styrene copolymer (ABS), polyamide (nylon), polyimide, and polyvinyl chloride (PVC).

The gas barrier film is a laminate in which gas barrier layers are provided on one or both surfaces of the substrate.

The material of the gas barrier layer is not particularly limited, and examples thereof include a silicon compound such as a polysilazane compound, a polycarbosilane compound, a polysilane compound, a polyorganosiloxane compound, or a tetraorganyl silane compound, an inorganic oxide such as silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, magnesium oxide, zinc oxide, indium oxide, or tin oxide, an inorganic nitride such as silicon nitride or aluminum nitride, an inorganic nitride oxide such as silicon nitride oxide, and a metal such as aluminum, magnesium, zinc, or tin. These may be used alone in 1 kind, or may be used in 2 or more kinds.

(organic EL element sealing Structure)

The organic EL element sealing structure according to the embodiment has a structure in which the organic EL layer is sealed by the sealing sheet described above.

Fig. 1 is a schematic cross-sectional view of an organic EL element sealing structure 10 according to an embodiment. The organic EL element sealing structure 10 shown in fig. 1 is a top emission type organic EL element sealing structure, and includes a laminate in which a substrate 20, a reflective electrode 30, an organic EL layer 40, and a transparent electrode 50 are sequentially laminated. The side surfaces and the upper surface of the laminate are sealed with a sealing layer 60, and a transparent substrate 70 is provided on the upper surface of the sealing layer 60.

The substrate 20 may be transparent or opaque. Examples of the material used for the substrate 20 include semiconductors such as metal, ceramic, glass, and silicon, and resins. Examples of the resin include polyethylene terephthalate, polymethyl methacrylate, polyolefin, acrylic resin, polyester resin, polyimide resin, and the like. Among them, by using polyolefin, acrylic resin, polyester resin, polyimide resin, or the like, the substrate can be made flexible. Further, by using a semiconductor such as silicon on the substrate 20 and forming a plurality of switching elements such as TFTs on the surface thereof, an active matrix drive type organic EL element sealing structure can be formed.

The reflective electrode 30 is formed of a material having light reflectivity, and functions as an anode. Examples of the material used for the reflective electrode 30 include metals, amorphous alloys, and microcrystalline alloys. Examples of the metal include Al, Ag, Mo, W, Ni, and Cr. Examples of the amorphous alloy include NiP, NiB, CrP, and CrB. Examples of the microcrystalline alloy include NiAl.

The organic EL layer 40 includes a hole transport layer 42, a light emitting layer 44, an electron transport layer 46, and an electron injection layer 48 in this order from the substrate 20 side.

The hole transport layer 42 is a layer having a function of transporting holes, and examples of the material thereof include triazole derivatives, oxadiazole derivatives, and imidazole derivatives. Further, a hole injection layer having a hole injection property may be provided between the reflective electrode 30 and the hole transport layer 42.

The light-emitting layer 44 is a layer that generates excitons by recombination of injected holes and electrons and emits light, and examples of the material include fluorescent whitening agents such as benzothiazoles, benzimidazoles, benzoxazoles, and the like, and metal-chelate oxygen-containing compounds.

The electron transport layer 46 is a layer having a function of transporting electrons, and examples of the material thereof include nitro-substituted fluorenone derivatives, anthraquinone dimethane derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, heterocyclic tetracarboxylic acid anhydrides such as naphthalene perylene, and the like.

The electron injection layer 48 is a layer having an electron injection property, and examples of the material thereof include an electron injection material such as an alkali metal, an alkaline earth metal, an alloy containing these metals, or an alkali metal fluoride.

SnO is used as the transparent electrode 50₂、In₂O₃ITO, IZO, ZnO: and a conductive metal oxide such as Al. In the case where the transparent electrode 50 is used as a cathode, it is preferable thatThe uppermost layer of the organic EL layer 40 is formed with the above-mentioned electron injection layer 48 to improve the electron injection efficiency.

The sealing layer 60 is formed of the sealing sheet of the above embodiment. In the case of forming the sealing layer 60 using the sealing sheet described above, the laminate including the organic EL layer 40 is covered with the adhesive layer after peeling off the protective layer or the like. After the transparent substrate 70 described later is laminated, the sealing layer 60 is brought into close contact with the substrate 20, the organic EL layer 40, and the transparent substrate 70 by pressure bonding using a press or the like. The pressure at the time of the pressure bonding process may be appropriately adjusted within a range in which the substrate 20, the organic EL layer 40, and the transparent substrate 70 are not damaged. Thereby, the sealing layer 60 sealing the organic EL layer 40 and the like is obtained.

The transparent substrate 70 is formed of a material transparent to light emitted from the organic EL layer 40. Examples of the material of the transparent substrate 70 include glass such as borosilicate glass and celadon glass, and resins such as polyethylene terephthalate, polymethyl methacrylate, polyolefin, acrylic resin, polyester resin, and polyimide resin. Among them, by forming the transparent substrate 70 using polyolefin, acrylic resin, polyester resin, or polyimide resin, the transparent substrate 70 can be made flexible.

In the organic EL element sealing structure 10 of the present embodiment, the organic EL layer 40 is sealed by the sealing layer 60 formed using the sealing sheet of the above embodiment, whereby the organic EL layer 40 can be reliably protected from moisture, and adhesion under high temperature and high humidity can be more reliably ensured, whereby improvement in reliability can be achieved over a long period of time.

The organic EL element sealing structure of the present embodiment can be used for various light emitting devices such as an organic EL display and an organic EL lighting.

While the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than the above-described configurations may be adopted.

For example, although the organic EL element sealing structure is a top emission type in the above embodiment, the substrate 20 may be a bottom emission type in which the arrangement of the reflective electrode 30 and the transparent electrode 50 is replaced by making the substrate transparent to light emitted from the organic EL layer 40.

Examples

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

< weight average molecular weight (Mw) >)

The Mw of the modified polyolefin resin was determined by gel permeation chromatography (GPC method) in terms of standard polystyrene under the following conditions.

The measurement device: HLC-8320GPC (manufactured by Tosoh)

GPC column composition: the four connecting columns below (all made by Tosoh)

(1) TSKgel HxL-H (guard column)

(2)TSKgel GMHxL

(3)TSKgel GMHxL

(4)TSKgel G2500HxL

Flow rate: 1.0mL/min

Column temperature: 40 deg.C

Sample concentration: 1.5% (w/v) (diluted with tetrahydrofuran)

Mobile phase solvent: tetrahydrofuran (THF)

Conversion to Standard polystyrene

Production example 1

100 parts by mass of a polyolefin resin (IIR: JSR BUTYL268, manufactured by JSR), 1.1 parts by mass of maleic anhydride, and 200 parts by mass of toluene were charged into a reaction apparatus equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen inlet pipe, and the temperature was raised to 85 ℃ by introducing nitrogen gas while stirring the solution. Then, 0.5 part by mass of t-butyl peroxy-2-ethylhexanoate was added, stirred at 85 ℃ for 2 hours, and then heated to 90 ℃ and stirred for 2 hours. Then, the resultant was cooled to obtain an acid-modified polyolefin resin solution 1. The weight average molecular weight of the obtained acid-modified polyolefin resin 1 was 25 ten thousand.

Production example 2

An acid-modified polyolefin resin solution 2 was obtained in the same manner as in production example 1, except that the amount of tert-butyl peroxy-2-ethylhexanoate used was 1.5 parts by mass. The weight average molecular weight of the obtained acid-modified polyolefin resin 2 was 13 ten thousand.

(production example 3)

An acid-modified polyolefin resin solution 3 was obtained in the same manner as in production example 1, except that the amount of tert-butyl peroxy-2-ethylhexanoate used was changed to 0.3 part by mass. The weight average molecular weight of the obtained acid-modified polyolefin resin 3 was 32 ten thousand.

(example 1)

The acid-modified polyolefin resin obtained in production example 1 was placed in a container so that the solid content was 100 parts by mass, and then 0.5 part by mass of an organic metal compound (ALCH: ethyl acetoacetate diisopropoxyaluminum, product of Kagaku corporation) and toluene were added to the mixture to obtain a solution containing a resin composition for sealing. The amount of toluene added was adjusted so that the solid content concentration of the solution became 30%.

The obtained solution containing the sealing resin composition was applied to a peeled PET film (thickness: 38 μm) so that the thickness thereof after drying became 50 μm, and dried at 90 ℃ for 3 minutes to form a pressure-sensitive adhesive layer. A PET film having a thickness of 25 μm was further bonded to the surface of the pressure-sensitive adhesive layer on the side to which the PET film subjected to the peeling treatment was not bonded, and the resultant was aged at 23 ℃ and 50% RH for 7 days to produce a sealing sheet (pressure-sensitive adhesive sheet).

(examples 2 to 10, comparative examples 1 to 3)

A sealing resin composition and a sealing sheet were produced in the same manner as in example 1, except that the composition of the components used was changed as described in table 1.

< adhesion >

The sealing sheets obtained in examples and comparative examples were cut into a width of 25mm and a length of 80mm to prepare test pieces. The PET film subjected to the peeling treatment was peeled from the obtained test piece, and the exposed adhesive layer was adhered to a glass plate (float plate glass, manufactured by TACT, Japan) whose surface was wiped with cotton impregnated with ethyl acetate and then left to stand at 23 ℃ under 50% RH for 1 hour, and a 2kg roller was reciprocated 3 times to be pressure-bonded. After the pressure bonding, the sheet was left to stand at 23 ℃ under 50% RH for 24 hours, and then the end of the sealing sheet (test piece) was pulled at an angle of 180 ℃ at a speed of 300mm/min with respect to the glass plate by a tensile tester (AG-X: Shimadzu corporation), and the adhesive force was measured at 23 ℃ under 50% RH.

< holding force >

The sealing sheets obtained in examples and comparative examples were cut into a width of 20mm to prepare test pieces. The peeled PET film was peeled from the obtained test piece, and the exposed adhesive layer was adhered to SUS with an adhesion area of 20mm × 20mm, and pressure-bonded by reciprocating 3 times with a 2kg roller. After the pressure-bonding, the glass plate was left to stand in a dry environment at 80 ℃/80 ℃ for 20 minutes, and then a load of 1kg was applied in the shearing direction of the pressure-sensitive adhesive layer 100 attached to the glass plate 110 under the same environment, and the offset amount of the pressure-sensitive adhesive layer 100 after 1 hour from the start of the application of the load (offset amount Δ P of the position P1 of the end portion of the pressure-sensitive adhesive layer 100 from the initial position P0 of the end portion of the pressure-sensitive adhesive layer 100 after 1 hour from the start of the application of the load) was measured as shown in fig. 2.

< substrate adhesion >

The sealing sheets obtained in examples and comparative examples were cut into a width of 25mm and a length of 80mm to prepare test pieces. The PET film subjected to the peeling treatment was peeled from the obtained test piece, and the exposed adhesive layer was adhered to a glass plate (float plate glass, manufactured by TACT, Japan) whose surface was wiped with cotton impregnated with ethyl acetate and then left to stand at 23 ℃ under 50% RH for 1 hour, and a 2kg roller was reciprocated 3 times to be pressure-bonded. After the pressure bonding, the sheet was left to stand at 60 ℃ under 90% RH for 24 hours, and then left to stand at 23 ℃ under 50% RH for 1 hour. Then, the end of the sealing piece (test piece) was pulled at an angle of 180 ° to the glass plate at a speed of 300mm/min under an atmosphere of 23 ℃ and 50% RH, and the adhesion to the substrate was evaluated according to the following criteria.

O: the sealing sheet peels at the interface of the glass and the adhesive layer.

And (delta): a portion of the adhesive layer is transferred to the glass.

X: the sealing sheet peeled off at the interface between the substrate (PET film) and the adhesive layer.

< constant load test >

The sealing sheets obtained in examples and comparative examples were cut into a size of 80mm × 20mm to obtain test pieces. The PET film subjected to the peeling treatment was peeled from the obtained test piece, and was adhered to a glass plate (float plate glass, manufactured by TACT, Japan) whose surface was wiped with ethyl acetate-impregnated cotton and which was then left for 1 hour at 23 ℃ under 50% RH so that the adhesion area was 50 mm. times.20 mm, and a 2kg roller was reciprocated 3 times for pressure bonding. After the pressure bonding, the test piece 200 was left to stand at 60 ℃ and 90% RH for 24 hours, and then, as shown in fig. 3, a weight 220 of 50g was hung on one end portion (end portion of the portion extruded from the glass plate 110) in the longitudinal direction of the test piece 200 stuck to the glass plate 210, and the amount Q of peeling from the one end portion of the glass plate 210 after the left to stand for 1 hour was measured.

< endurance test >

The sealing sheets obtained in examples and comparative examples were cut into a size of 50mm × 50mm to obtain test pieces. The PET film subjected to the peeling treatment was peeled from the obtained test piece, and was attached to a glass plate (float plate glass, manufactured by TACT, Japan) which was wiped with cotton wetted with ethyl acetate and then left for 1 hour at 23 ℃ under 50% RH, and a 2kg roller was pressed and pressed in a reciprocating manner 3 times. After the pressure bonding, the sheet was left to stand at 85 ℃ and 85% RH for 500 hours, and then the durability was evaluated according to the following criteria.

O: no abnormalities were observed in appearance.

And (delta): appearance defects such as foaming, lifting, and peeling were slightly observed, but there was no problem in actual use.

X: appearance defects such as foaming, lifting, and peeling were observed over a wide range.

< haze >

The sealing sheets obtained in examples and comparative examples were cut into a size of 50mm × 50mm, and the PET film after the peeling treatment was peeled off. Thereafter, the haze was measured. The haze was measured using MH-150 (color technical research, village).

TABLE 1

The acronyms or material names shown in table 1 are as follows.

ALCH: ethyl acetoacetate diisopropoxyaluminum, AIPD manufactured by Chuangzhen Fine Chemicals, Ltd: aluminum isopropoxide; manufactured by Chuanjian Fine chemical Co., Ltd

Aluminum chelating agent A: aluminum tris (acetylacetonate); manufactured by Chuanjian Fine chemical Co., Ltd

TH-130: a terpene-phenolic tackifying resin YS polymer TH-130; chemical system of YASUHARA

R100: an aliphatic hydrocarbon tackifying resin Quintone R100; manufactured by Nippon Rukusnezoff

The sealing sheets of examples 1 to 10 were excellent in moisture permeability by containing the modified polyolefin resin.

As shown in Table 1, the adhesive strength of the sealing sheets of examples 1 to 10 was significantly higher than that of comparative example 2. Further, it was confirmed that the retention force, the substrate adhesion, and the constant load test results of the sealing sheets of examples 1 to 10 were good after passing through a high-temperature and high-humidity environment, and the durability was excellent. In addition, examples 1 to 5 and 7 to 10 were excellent in durability and also confirmed to have excellent permeability.

Description of the reference numerals

10 organic EL element sealing structure, 20 substrate, 30 reflective electrode, 40 organic EL layer, 42 hole transport layer, 44 light emitting layer, 46 electron transport layer, 48 electron injection layer, 50 transparent electrode, 60 sealing layer, 70 transparent substrate, 100 test piece, 110 glass plate, 200 test piece, 210 glass plate, 220 weight.