JP2009076436A - Sealing method for environment-sensitive device, and image display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing method for an environment-sensitive device, which prevents intrusion of moisture or oxygen from adhesive layers. <P>SOLUTION: The sealing method for an environment-sensitive device is used to seal an environment-sensitive device 1 by a gas-barrier film 4 having a barrier layer including an organic region and an inorganic region, via adhesive layers 2, 3 including a group-II oxide-based moisture absorbent and/or a deoxidizer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealing method for an environmentally sensitive device such as an organic EL element and an image display element.

Environmentally sensitive devices such as organic EL elements, liquid crystal display elements, display elements such as electronic paper, etc. are sealed to prevent moisture because the light-emitting materials and electrode materials used as raw materials are easily deteriorated by gas components such as water vapor. Stopping is a big problem in practical use. Here, use of a gas barrier film having at least one organic layer and at least one inorganic layer as a sealing film has been studied (Patent Document 1). However, when such an organic-inorganic laminated gas barrier film is used as a sealing film for an environmentally sensitive device, it is necessary to use an adhesive layer for adhering the sealing film, and moisture and oxygen enter from the adhesive layer. There exists a problem that an element will deteriorate.
On the other hand, Patent Document 2 describes that the surface of an organic EL element is coated with a UV cured film, and further describes that a hygroscopic agent is added to the UV cured film.

US Pat. No. 6,268,695 Japanese Patent Laid-Open No. 11-40344

An object of the present invention is to solve the above-mentioned problems, and is a method for sealing an environment-sensitive device using an organic-inorganic laminated gas barrier film, and intrusion of moisture and oxygen from an adhesive layer Provided is a method for sealing an environmentally sensitive device capable of suppressing the above.
Moreover, the image display element sealed with the organic inorganic laminated type gas barrier film is provided.

As a result of intensive studies by the inventor under the above problems, the above problems can be solved by the following means.
(1) The environment-sensitive device is sealed with a gas barrier film having a barrier layer including an organic region and an inorganic region through an adhesive layer including a group 2 oxide-based hygroscopic agent and / or an oxygen scavenger. A method for sealing an environmentally sensitive device.
(2) An environment characterized in that an environment-sensitive device is sealed with a gas barrier film having a barrier layer containing an organic region and an inorganic region through an adhesive layer containing a Group 2 oxide-based hygroscopic agent and an oxygen scavenger. Method for sealing a sensitive device.
(3) The environment-sensitive device sealing according to (1) or (2), wherein the barrier layer including the organic region and the inorganic region has at least one organic layer and at least one inorganic layer. Stop method.
(4) The method for sealing an environmentally sensitive device according to any one of (1) to (3), wherein the oxygen scavenger is an iron-based oxygen scavenger.
(5) The environment-sensitive device is an image display element having a display part and a non-display part, including an oxygen scavenger in an adhesive layer provided on the non-display part, The sealing method of the environment sensitive device according to any one of (1) to (4), wherein the provided adhesive layer does not include an oxygen scavenger.
(6) The environment-sensitive device sealing method according to any one of (1) to (5), wherein the group 2 oxide-based hygroscopic agent is calcium oxide or strontium oxide.
(7) The environment-sensitive device sealing method according to any one of (1) to (6), wherein the environment-sensitive device is an organic EL element.
(8) An image display element sealed with a gas barrier film through an adhesive layer,
The gas barrier film has an organic region and an inorganic region,
The image display element includes a display portion and a non-display portion, an adhesive layer provided on the display portion includes an oxygen scavenger and a group 2 oxide-based hygroscopic agent, and is provided on the non-display portion. An image display element that does not contain an oxygen scavenger in the adhesive layer formed.
(9) The image display element according to (8), wherein the oxygen scavenger is iron-based.
(10) The image display element according to (8) or (9), wherein the adhesive layer contains 80 to 90% by weight of an adhesive and 10 to 20% by weight of a Group 2 oxide-based moisture absorbent.
(11) The image display device according to any one of (8) to (10), wherein the group 2 oxide-based moisture absorbent is calcium oxide or strontium oxide.
(12) The image display element according to any one of (8) to (11), wherein the image display element is an organic EL element.

  According to the present invention, it is possible to effectively prevent moisture and oxygen from entering from the adhesive layer, and to effectively seal the environment sensitive device by the gas barrier film.

  Hereinafter, the contents of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

  The environment-sensitive device in the present invention is sealed with an organic / inorganic laminated gas barrier film through an adhesive layer, and the adhesive layer contains a Group 2 oxide moisture absorbent and an oxygen scavenger.

(Gas barrier film)
The gas barrier film in the present invention is a film having a function of blocking oxygen and moisture in the atmosphere. The gas barrier film in the present invention is a film in which a gas barrier layer is provided on at least one surface of a base film. Here, the gas barrier layer may be any layer as long as it is known to have gas barrier ability, but is preferably an organic-inorganic laminate in which organic regions and inorganic regions or organic layers and inorganic layers are alternately laminated.
The organic / inorganic laminated gas barrier film has a structure in which an organic region and an inorganic region or at least one organic layer and at least an inorganic layer are laminated.
Organic regions and inorganic regions or organic layers and inorganic layers are usually laminated alternately. In the case of an organic region and an inorganic region, a so-called gradient material layer in which each region continuously changes in the film thickness direction may be used. As an example of the gradient material, a paper by Kim et al. “Journal of Vacuum Science and Technology A Vol. 23 p971-977 (2005 American Vacuum Society) Journal of Vacuum Science and Technology A Vol. , American Vacuum Society) ”or a continuous layer in which the organic layer and the inorganic layer do not have an interface as disclosed in the specification of US Published Patent No. 2004-46497. Hereinafter, for simplification, the organic layer and the organic region are described as “organic layers”, and the inorganic layer and the inorganic region are described as inorganic layers.
Although there is no restriction | limiting in particular regarding the number of layers which comprises a cas barrier film, Typically 2-30 layers are preferable, and 3-20 layers are more preferable. In addition, the barrier layer may be provided only on one side of the plastic film, or may be provided on both sides.

(Base film)
The gas barrier film in the present invention usually uses a plastic film as the base film. The plastic film to be used is not particularly limited in material, thickness and the like as long as it can hold a laminate such as an organic layer and an inorganic layer, and can be appropriately selected according to the purpose of use. Specifically, as the plastic film, metal support (aluminum, copper, stainless steel, etc.) polyester resin, methacrylic resin, methacrylic acid-maleic acid copolymer, polystyrene resin, transparent fluororesin, polyimide, fluorinated polyimide resin , Polyamide resin, polyamideimide resin, polyetherimide resin, cellulose acylate resin, polyurethane resin, polyetheretherketone resin, polycarbonate resin, alicyclic polyolefin resin, polyarylate resin, polyethersulfone resin, polysulfone resin, cycloolefin Examples thereof include thermoplastic resins such as filn copolymers, fluorene ring-modified polycarbonate resins, alicyclic ring-modified polycarbonate resins, fluorene ring-modified polyester resins, and acryloyl compounds.

  The gas barrier film in the present invention is preferably made of a heat-resistant material such as a plastic film. Specifically, it is preferable that the glass transition temperature (Tg) is 100 ° C. or higher and / or the linear thermal expansion coefficient is 40 ppm / ° C. or lower and is made of a transparent material having high heat resistance. Tg and a linear expansion coefficient can be adjusted with an additive. As such a thermoplastic resin, for example, polyethylene naphthalate (PEN: 120 ° C.), polycarbonate (PC: 140 ° C.), alicyclic polyolefin (for example, ZEONOR 1600: 160 ° C. manufactured by Nippon Zeon Co., Ltd.), polyarylate ( PAr: 210 ° C., polyethersulfone (PES: 220 ° C.), polysulfone (PSF: 190 ° C.), cycloolefin copolymer (COC: Japanese Patent Application Laid-Open No. 2001-150584 compound: 162 ° C.), polyimide (for example, Mitsubishi Gas Chemical) Neoprim: 260 ° C.), fluorene ring-modified polycarbonate (BCF-PC: compound of JP 2000-227603 A: 225 ° C.), alicyclic modified polycarbonate (IP-PC: compound of JP 2000-227603 A) : 205 ° C), acryloyl compound (Compound described in JP-A 2002-80616: 300 ° C. or more) (the parenthesized data are Tg). In particular, when transparency is required, it is preferable to use an alicyclic polyolefin or the like.

  When the gas barrier film of the present invention is used in combination with a polarizing plate, it is preferable that the barrier laminate of the gas barrier film faces the inside of the cell and is arranged on the innermost side (adjacent to the element). At this time, since the gas barrier film is disposed inside the cell from the polarizing plate, the retardation value of the gas barrier film is important. The usage form of the gas barrier film in such an embodiment includes a gas barrier film using a base film having a retardation value of 10 nm or less and a circularly polarizing plate (1/4 wavelength plate + (1/2 wavelength plate) + linearly polarizing plate. ) Or a linear barrier plate combined with a gas barrier film using a base film having a retardation value of 100 nm to 180 nm, which can be used as a quarter wavelength plate.

As a base film having a retardation of 10 nm or less, cellulose triacetate (Fuji Film Co., Ltd .: Fuji Tac), polycarbonate (Teijin Chemicals Co., Ltd .: Pure Ace, Kaneka: Elmec Co., Ltd.), cycloolefin polymer (JSR Co., Ltd.) ): Arton, Nippon Zeon Co., Ltd .: Zeonoa), cycloolefin copolymer (Mitsui Chemicals Co., Ltd .: Appel (pellet), Polyplastic Co., Ltd .: Topas (pellet)) Polyarylate (Unitika Co., Ltd.): U100 (pellet) )), Transparent polyimide (Mitsubishi Gas Chemical Co., Ltd .: Neoprim) and the like.
Moreover, as a quarter wavelength plate, the film adjusted to the desired retardation value by extending | stretching said film suitably can be used.

The base film in the present invention is required to be transparent when used in an image display element. That is, the light transmittance is usually 80% or more, preferably 85% or more, and more preferably 90% or more. The light transmittance is calculated by measuring the total light transmittance and the amount of scattered light using the method described in JIS-K7105, that is, an integrating sphere light transmittance measuring device, and subtracting the diffuse transmittance from the total light transmittance. be able to.
The environment-sensitive device of the present invention does not necessarily require transparency depending on the application. Therefore, in such a case, an opaque material can be used as the plastic film. Examples of the opaque material include polyimide, polyacrylonitrile, and known liquid crystal polymers.
The thickness of the plastic film used for the gas barrier film in the present invention is not particularly limited because it is appropriately selected depending on the use, but is typically 1 to 800 μm, preferably 10 to 200 μm. These plastic films may have functional layers such as a transparent conductive layer and a primer layer. The functional layer is described in detail in paragraph numbers 0036 to 0038 of JP-A-2006-289627. Examples of functional layers other than these include matting agent layers, protective layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, hard coat layers, stress relaxation layers, antifogging layers, and antifouling layers. , Printing layer, easy adhesion layer and the like.

Inorganic layer The inorganic layer is not particularly limited as long as it is composed of an inorganic material and has gas barrier properties. Typically, the inorganic substance includes boron, magnesium, aluminum, silicon, titanium, zinc, tin oxide, nitride, oxynitride, carbide, hydride, and the like. These may be pure substances, or may be a mixture of multiple compositions or a gradient material layer. Of these, aluminum oxide, nitride or oxynitride, or silicon oxide, nitride or oxynitride is preferable. Although it does not specifically limit regarding the thickness of each inorganic layer which comprises a gas barrier film, Typically, it is preferable to exist in the range of 5 nm-500 nm per layer, More preferably, it is 10 nm-200 nm per layer.

As a method for forming the inorganic layer, any method can be used as long as the target thin film can be formed. For example, a sol-gel method, a sputtering method, a vacuum deposition method, an ion plating method, a plasma CVD method, and the like are suitable, and specifically, Japanese Patent Registration No. 3400324, Japanese Patent Application Laid-Open No. 2002-322561, Japanese Patent Application Laid-Open No. 2002-361774. Can be employed.
In particular, when a silicon compound is formed, it is preferable to employ any one of inductively coupled plasma CVD, PVD or CVD using a microwave and a magnetic field-applied plasma set to electron cyclotron resonance conditions, Most preferably, a formation method by inductively coupled plasma CVD is employed. CVD (ECR-CVD) using microwaves set to inductively coupled plasma CVD or electron cyclotron resonance conditions and plasma applied with a magnetic field is described in, for example, Chemical Society of Japan, CVD Handbook, p. 284 (1991). It can be implemented by the method. PVD (ECR-PVD) using microwaves set to electron cyclotron resonance conditions and plasma applied with a magnetic field is, for example, Ono et al., Jpn. J. Appl. Phys. 23, No. 8, L534 ( 1984). As a raw material when using the CVD, a gas source such as silane or a liquid source such as hexamethyldisilazane can be used as a silicon supply source.

Organic layer It is preferable that the gas barrier film in this invention has an organic layer. In order to improve the brittleness and barrier property of the inorganic layer made of the above-mentioned inorganic substance, one or more organic layers are provided adjacent to the organic layer.

  The organic layer is formed using (1) a method using an inorganic oxide layer prepared by a sol-gel method, (2) a method in which an organic substance is laminated by coating or vapor deposition, and then cured by ultraviolet rays or an electron beam. can do. In addition, (1) and (2) may be used in combination. For example, after forming a thin film on the resin film by the method (1), an inorganic oxide layer is formed, and then (2) A thin film may be formed by a method. Hereinafter, these methods will be described in order.

(1) Sol-gel method The sol-gel method is a method in which a metal alkoxide is preferably hydrolyzed and polycondensed in a solution or in a coating film to obtain a dense thin film. At this time, an organic-inorganic hybrid material may be used in combination with a resin.

  Examples of the metal alkoxide used in the sol-gel method include alkoxysilane and / or metal alkoxide other than alkoxysilane. As the metal alkoxide other than alkoxysilane, zirconium alkoxide, titanium alkoxide, aluminum alkoxide and the like are preferable.

  The polymer used in combination during the sol-gel reaction preferably has a hydrogen bond forming group. Examples of resins having hydrogen bond-forming groups include hydroxyl group-containing polymers and derivatives thereof (polyvinyl alcohol, polyvinyl acetal, ethylene-vinyl alcohol copolymers, phenol resins, methylol melamine, and derivatives thereof); carboxyl groups Polymers and derivatives thereof (mono or copolymers containing units of polymerizable unsaturated acids such as poly (meth) acrylic acid, maleic anhydride, itaconic acid, and esterified products of these polymers (vinyl esters such as vinyl acetate, Homo- or copolymers containing units such as (meth) acrylic acid esters such as methyl methacrylate)); polymers having an ether bond (polyalkylene oxide, polyoxyalkylene glycol, polyvinyl ether, silicon resin, etc.); amide bond Having a polymer (> N COR) -bond (wherein R represents a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent) N- of polyoxazoline or polyalkyleneimine Acylated product);> polyvinylpyrrolidone having a NC (O) -bond and derivatives thereof; polyurethane having a urethane bond; polymer having a urea bond, and the like.

  Alternatively, an organic-inorganic hybrid material can be prepared by using a monomer in combination during the sol-gel reaction and polymerizing the monomer during or after the sol-gel reaction.

During the sol-gel reaction, the metal alkoxide is hydrolyzed and polycondensed in water and an organic solvent. At this time, it is preferable to use a catalyst. As the hydrolysis catalyst, an acid (organic or inorganic acid) is generally used.
The amount of the acid used is 0.0001 to 0.05 mol per 1 mol of metal alkoxide (alkoxysilane and other metal alkoxide in the case of containing alkoxysilane and other metal alkoxide), and preferably is 0.00. 001-0.01 mol. After hydrolysis, a basic compound such as an inorganic base or an amine may be added to bring the pH of the solution to near neutrality to promote condensation polymerization.

In addition, other sol-gel catalysts such as metal chelate compounds having Al, Ti, and Zr as the central metal, organometallic compounds such as tin compounds, and metal salts such as alkali metal salts of organic acids can be used in combination.
The proportion of the sol-gel catalyst in the composition is preferably 0.01 to 50% by mass, more preferably 0.1 to 50% by mass, and still more preferably 0.5 to 10%, based on the alkoxysilane that is the raw material of the sol liquid. % By mass.

  Next, the solvent used for the sol-gel reaction will be described. The solvent uniformly mixes each component in the sol liquid, adjusts the solid content of the composition, and at the same time allows it to be applied to various coating methods to improve the dispersion stability and storage stability of the composition. . These solvents are not particularly limited as long as they can fulfill the above purpose. Preferable examples of these solvents include water and organic solvents that are highly miscible with water.

For the purpose of adjusting the speed of the sol-gel reaction, an organic compound capable of multidentate coordination may be added to stabilize the metal alkoxide. Examples of organic compounds capable of multidentate coordination include β-diketones and / or β-ketoesters, and alkanolamines.
Specific examples of the β-diketones and / or β-ketoesters include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate. Acetic acid-sec-butyl, acetoacetic acid-tert-butyl, 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane -Dione, 5-methyl-hexane-dione and the like can be mentioned. Of these, ethyl acetoacetate and acetylacetone are preferred, and acetylacetone is particularly preferred. These β-diketones and / or β-ketoesters may be used alone or in combination of two or more.
These compounds capable of multidentate coordination can also be used for the purpose of adjusting the reaction rate when the metal chelate compound is used as a sol-gel catalyst.

  Next, a method for coating the sol-gel reaction composition will be described. The sol solution can form a thin film on the transparent film by a coating method such as curtain flow coating, dip coating, spin coating or roll coating. In this case, the hydrolysis may be performed at any time during the production process. For example, a solution of a required composition is hydrolyzed and partially condensed to prepare a desired sol solution, which is applied and dried, and a solution of the required composition is prepared and dried while hydrolyzing and partially condensing simultaneously. Method, application-After primary drying, a method of applying a water-containing liquid necessary for hydrolysis repeatedly and applying hydrolysis can be suitably employed. In addition, the coating method can take various forms. However, when productivity is important, each of the lower layer coating solution and the upper layer coating solution is required on a slide Geyser having a multistage discharge port. A method (simultaneous multi-layer method) is preferably used in which the discharge flow rate is adjusted so that the coating amount is obtained, and the formed multilayer flow is continuously placed on a support and dried.

  The drying temperature after coating is preferably 150 to 350 ° C, more preferably 150 to 250 ° C, and still more preferably 150 to 200 ° C.

In order to make the film after coating and drying more dense, irradiation with energy rays may be performed. Although there is no restriction | limiting in particular in the kind of irradiation radiation, In consideration of the influence with respect to a deformation | transformation and modification | denaturation of a support body, irradiation of an ultraviolet-ray, an electron beam, or a microwave can be used especially preferable. The irradiation intensity is ^{30mJ / cm 2 ~500mJ / cm 2} , particularly preferably ^{50mJ / cm 2 ~400mJ / cm 2} . The irradiation temperature can be employed without limitation between room temperature and the deformation temperature of the support, and is preferably 30 ° C to 150 ° C, particularly preferably 50 ° C to 130 ° C.

(2) Method of Laminating Organic Material by Application or Vapor Deposition and then Curing with Ultraviolet Ray or Electron Beam A method of forming an organic layer mainly composed of a polymer obtained by crosslinking monomers is described. The monomer used in this method is not particularly limited as long as it contains a group that can be cross-linked by ultraviolet rays or an electron beam, but it is preferable to use a monomer having an acryloyl group, a methacryloyl group, or an oxetane group. For example, epoxy (meth) acrylate, urethane (meth) acrylate, isocyanuric acid (meth) acrylate, pentaerythritol (meth) acrylate, trimethylolpropane (meth) acrylate, ethylene glycol (meth) acrylate, polyester (meth) acrylate, etc. Among these, it is preferable that a polymer obtained by crosslinking a monomer having a bifunctional or higher functional acryloyl group or methacryloyl group as a main component. These monomers having a bifunctional or higher functional acryloyl group or methacryloyl group may be used as a mixture of two or more kinds, or as a mixture of monofunctional (meth) acrylates.
Moreover, as a monomer which has oxetane group, it is preferable to use the monomer which has a structure described in Unexamined-Japanese-Patent No. 2002-356607 General formula (3)-(6). In this case, you may mix these arbitrarily.

  In addition, from the viewpoint of heat resistance and solvent resistance required for display applications, it is mainly composed of isocyanuric acid acrylate, epoxy acrylate, urethane acrylate having a high degree of crosslinking and a glass transition temperature of 200 ° C. or higher. Further preferred.

  Specific examples of the monomer represented by the general formula (1) are shown below, but the present invention is not limited to these.

 Although it does not specifically limit about organic layer thickness, 10 nm-5000 nm are preferable, More preferably, it is 10-2000 nm, Most preferably, it is 10 nm-5000 nm. If the thickness of the organic layer is too thin, it will be difficult to obtain thickness uniformity, so that structural defects in the inorganic layer cannot be efficiently filled with the organic layer, and improvement in barrier properties may not be seen. is there. Conversely, if the organic layer is too thick, the organic layer is likely to crack due to an external force such as bending, which may cause a problem that the barrier property is lowered.

(Formation method of organic layer)
A method for forming the organic layer is not particularly defined, but for example, it can be formed by a solution coating method or a vacuum film forming method. Examples of the solution coating method include a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, a slide coating method, or a method described in US Pat. No. 2,681,294. It can apply | coat by the extrusion coat method which uses a hopper. Although there is no restriction | limiting in particular as a vacuum film-forming method, Film-forming methods, such as vapor deposition and plasma CVD, are preferable. In the present invention, a polymer may be applied by solution, or a hybrid coating method containing an inorganic substance as disclosed in Japanese Patent Application Laid-Open Nos. 2000-323273 and 2004-25732 may be used.

 In addition to the above, the gas barrier film used in the present invention is provided with a desired functional layer on the outermost side of the film between the base film, the organic layer, the inorganic layer, or between the gas barrier film and the adhesive layer. can do. Examples of such a functional layer include a smoothing layer, an adhesion improving layer, an antireflection layer and the like as described in the base film.

Water vapor permeability at 40 ° C. · 90% relative humidity of the gas barrier film used in the present invention is preferably not more than 0.01g / m ² · day, more preferably at most 0.001g / m ² · day 0.0001 g / m ² · day or less is particularly preferable.
Moreover, it is preferable that it is 10-500 micrometers, and, as for the thickness of the gas barrier film used by this invention, it is more preferable that it is 50-250 micrometers.

Adhesive The adhesive layer is a layer mainly composed of an adhesive, and usually 70% by weight or more of the adhesive layer is an adhesive, and 80 to 90% by weight of the adhesive layer is an adhesive. Is preferred.
As the adhesive, those used as adhesives for environmentally sensitive devices can be widely used, and an epoxy adhesive is preferable. Here, examples of the epoxy adhesive include a thermosetting type and an ultraviolet curing type. When the barrier film absorbs ultraviolet rays, a thermosetting type is preferable. Among thermosetting types, there are a one-component type and a two-component mixed type, and any of them is preferably used in the present invention. In the present invention, an adhesive that becomes colorless and transparent after curing is preferred. Examples of commercially available products include Epotech series made by Daizonichimomori, XNR-5000 series made by Nagase ChemteX, and 3000 series made by ThreeBond.

Group 2 Oxide Hygroscopic Agent In the present invention, the adhesive layer contains a Group 2 oxide hygroscopic agent. As the Group 2 oxide moisture absorbent, calcium oxide and strontium oxide are preferable. Examples of commercially available products include Wako Pure Chemical Reagents, Aldrich Reagents, Kanto Chemical Reagents (both powders), and the like. By using such a group 2 oxide, the effect of efficiently suppressing the generation of dark spots can be obtained. In the present invention, an adhesive containing a Group 2 oxide-based hygroscopic agent may be used.
The group 2 oxide-based hygroscopic agent is preferably contained in the adhesive layer in a proportion of 5 to 30% by weight, more preferably in a proportion of 10 to 20% by weight. .

Oxygen scavenger In the present invention, the adhesive layer contains an oxygen scavenger. As the oxygen scavenger, unsaturated polymer-based and iron-based oxygen scavengers are preferable, and iron-based oxygen scavengers are more preferable. Examples of commercially available products include Mitsubishi Gas Chemical's Ageless series. The oxygen scavenger is preferably contained in the adhesive layer in a proportion of 5 to 30% by weight, and more preferably in a proportion of 10 to 20% by weight.
The adhesive layer may contain components other than those described above, and examples thereof include a dye, an ultraviolet absorber, and a filler.

Position containing a Group 2 oxide-based hygroscopic agent and oxygen scavenger When sealing an image display element that is an environmentally sensitive device with an organic-inorganic laminated gas barrier film, a Group 2 oxide-based hygroscopic agent and oxygen scavenger is included in the adhesive layer Coexisting with hygroscopic agents because general oxygen scavengers (iron-based, ascorbic acid-based, gallic acid-based, etc.) require moisture to exert their oxygen scavenging function. Below, the deoxygenation effect is small. On the other hand, the resin-oxidized oxygen scavenger (polymer having an unsaturated bond) does not require moisture, but has a small oxygen scavenging effect.
Therefore, when used for an image display element, the adhesive layer provided on the non-display part on the image display element contains an oxygen scavenger, and the adhesive layer provided on the display part is detached. It is preferable that the composition does not include an oxygen agent. This point will be described in more detail with reference to FIG. The present invention is not limited to FIG.

FIGS. 1A and 1B are schematic views of an image display element sealed with an organic / inorganic laminated gas barrier film, and FIG. 1B is a diagram viewed from the top when FIG. It becomes. In FIG. 1, 1 is an image display element, 2 and 3 are adhesive layers, and 4 is an organic-inorganic laminated gas barrier film. Here, as shown in FIG. 2, the image display element 1 usually has a structure in which a display unit 12 is provided on a substrate 11. In the present invention, the portion of the adhesive layer 3 provided on the display portion 12 and the portion other than the display portion, that is, the portion of the adhesive layer 2 provided on the non-display portion, It is preferable to change the composition. When this is viewed from the direction of FIG. 1B, the composition of the adhesive layer changes as shown in FIG. 1B at the peripheral portion (non-display portion 2) and the central portion (display portion 3). Specifically, the adhesive layer provided on the non-display portion includes an oxygen scavenger, and the adhesive layer provided on the display portion does not include an oxygen scavenger. As described above, by disposing an oxygen scavenger around the adhesive layer, both moisture and oxygen can be blocked without adversely affecting the display quality. In particular, when the gas barrier performance of the gas barrier film is high, the intrusion of moisture and oxygen from the adhesive layer is likely to enter from the periphery in the cross-sectional direction of the layer, not the layer stacking direction. It is effective to suppress. As a result, the device can be isolated from water and oxygen without degrading the display quality of the device.
The oxygen scavenger is preferably contained in the adhesive layer provided on the non-display part in a proportion of 5 to 30% by weight in the non-display part adhesive layer, and in a proportion of 10 to 20% by weight. More preferably it is included.

  The group 2 oxide-based hygroscopic agent may be included in both the display part and the non-display part, or may be included only in one, and if it is included only in one, it is better to include it in the display part. preferable. In the present invention, it is particularly preferable to combine the display portion with a group 2 oxide moisture absorbent and the non-display portion with an oxygen scavenger.

(Environmentally sensitive device)
The environment-sensitive device in the present invention refers to a device whose performance changes under the influence of substances present in the environment, such as oxygen and moisture, such as an image display element, an organic memory, an organic battery, and an organic solar battery. Can be mentioned.
The image display element in the present invention means a circularly polarizing plate / liquid crystal display element, a touch panel, an organic EL element and the like.

Circularly polarizing plate A circularly polarizing plate can be produced by laminating a λ / 4 plate and a polarizing plate using the gas barrier film of the present invention as a substrate. In this case, the lamination is performed so that the slow axis of the λ / 4 plate and the absorption axis of the polarizing plate are 45 °. As such a polarizing plate, one that is stretched in a direction of 45 ° with respect to the longitudinal direction (MD) is preferably used. For example, those described in JP-A-2002-865554 can be suitably used. .

Liquid crystal display element A reflective liquid crystal display device has a configuration comprising, in order from the bottom, a lower substrate, a reflective electrode, a lower alignment film, a liquid crystal layer, an upper alignment film, a transparent electrode, an upper substrate, a λ / 4 plate, and a polarizing film. . The gas barrier film in the present invention can be used as the transparent electrode substrate and the upper substrate. In the case of color display, it is preferable to further provide a color filter layer between the reflective electrode and the lower alignment film, or between the upper alignment film and the transparent electrode.
The transmissive liquid crystal display device includes, in order from the bottom, a backlight, a polarizing plate, a λ / 4 plate, a lower transparent electrode, a lower alignment film, a liquid crystal layer, an upper alignment film, an upper transparent electrode, an upper substrate, a λ / 4 plate, and a polarization It has the structure which consists of a film | membrane. Of these, the substrate of the present invention can be used as the upper transparent electrode and the upper substrate. In the case of color display, it is preferable to further provide a color filter layer between the lower transparent electrode and the lower alignment film, or between the upper alignment film and the transparent electrode.
The type of the liquid crystal cell is not particularly limited, but more preferably TN (Twisted Nematic) type, STN (Super Twisted Nematic) type, HAN (Hybrid Aligned Nematic) type, VA (Vertically Alignment) type, ECB type (Electrically Controlled Birefringence) OCB type (Optically Compensated Bend), CPA type (Continuous Pinwheel Alignment), and IPS type (In Plane Switching) are preferable.

Touch Panel The touch panel can be applied to those described in JP-A-5-127822, JP-A-2002-48913, and the like.

Organic EL element An organic EL element means an organic electroluminescence element. The gas barrier film in this invention becomes a sealing film of an organic EL element. The organic EL element has a cathode and an anode on a substrate, and an organic compound layer including a light emitting layer between both electrodes. Due to the nature of the light emitting element, at least one of the anode and the cathode is transparent.

 As an aspect of lamination of the organic compound layer in the present invention, an aspect in which a hole transport layer, a light emitting layer, and an electron transport layer are laminated in this order from the anode side is preferable. Furthermore, a charge blocking layer or the like may be provided between the hole transport layer and the light-emitting layer, or between the light-emitting layer and the electron transport layer. A hole injection layer may be provided between the anode and the hole transport layer, and an electron injection layer may be provided between the cathode and the electron transport layer. Further, the light emitting layer may be a single layer, or the light emitting layer may be divided into a first light emitting layer, a second light emitting layer, a third light emitting layer, and the like. Furthermore, each layer may be divided into a plurality of secondary layers.

Next, each element which comprises an organic EL element is demonstrated in detail.
Substrate As a substrate used in the organic EL element in the present invention, a substrate used in a known organic EL element can be widely adopted. The organic EL substrate may be a resin film or a gas barrier film. In the case of a gas barrier film, in addition to the gas barrier film in the above-described sealing film, described in JP-A No. 2004-136466, JP-A No. 2004-148766, JP-A No. 2005-246716, JP-A No. 2005-262529, and the like. The gas barrier film can also be preferably used.

  Although the thickness of the board | substrate used by this invention is not prescribed | regulated in particular, 30 micrometers-700 micrometers are preferable, More preferably, they are 40 micrometers-200 micrometers, More preferably, they are 50 micrometers-150 micrometers. Further, in any case, the haze is preferably 3% or less, more preferably 2% or less, further preferably 1% or less, and the total light transmittance is preferably 70% or more, more preferably 80% or more, and further preferably 90%. That's it.

Anode The anode usually has a function as an electrode for supplying holes to the organic compound layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light-emitting element. Thus, it can be appropriately selected from known electrode materials. As described above, the anode is usually provided as a transparent anode. The transparent anode is described in detail in Yutaka Sawada's “New Development of Transparent Electrode Film” published by CMC (1999). When using a plastic substrate with low heat resistance as the substrate, ITO or IZO is used, and a transparent anode formed at a low temperature of 150 ° C. or lower is preferable.

Cathode The cathode usually has a function as an electrode for injecting electrons into the organic compound layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light-emitting element. , Can be appropriately selected from known electrode materials.

 Examples of the material constituting the cathode include metals, alloys, metal oxides, electrically conductive compounds, and mixtures thereof. Specific examples include Group 2 metals (eg, Mg, Ca, etc.), gold, silver, lead, aluminum, lithium-aluminum alloys, magnesium-silver alloys, rare earth metals such as indium, ytterbium, and the like. These may be used alone, but two or more can be suitably used in combination from the viewpoint of achieving both stability and electron injection.

Among these, as a material constituting the cathode, a material mainly composed of aluminum is preferable.
The material mainly composed of aluminum refers to aluminum alone or an alloy of aluminum and 0.01 to 10% by mass of an alkali metal or a Group 2 metal (for example, lithium-aluminum alloy, magnesium-aluminum alloy, etc.). The cathode material is described in detail in JP-A-2-15595 and JP-A-5-121172. Further, a dielectric layer made of a fluoride or oxide of an alkali metal or a Group 2 metal may be inserted between the cathode and the organic compound layer with a thickness of 0.1 to 5 nm. This dielectric layer can also be regarded as a kind of electron injection layer.

The thickness of the cathode can be appropriately selected depending on the material constituting the cathode and cannot be generally defined, but is usually about 10 nm to 5 μm, and preferably 50 nm to 1 μm.
Further, the cathode may be transparent or opaque. The transparent cathode can be formed by depositing a thin cathode material to a thickness of 1 to 10 nm and further laminating a transparent conductive material such as ITO or IZO.

Light-Emitting Layer The organic EL element has at least one organic compound layer including a light-emitting layer, and as the organic compound layer other than the organic light-emitting layer, as described above, a hole transport layer, an electron transport layer, a charge Examples of the layer include a block layer, a hole injection layer, and an electron injection layer.

-Organic light emitting layer-
The organic light-emitting layer receives holes from the anode, the hole injection layer, or the hole transport layer when an electric field is applied, and receives electrons from the cathode, the electron injection layer, or the electron transport layer, and recombines the holes and electrons. It is a layer having a function of providing light and emitting light. The light emitting layer may be composed of only the light emitting material, or may be a mixed layer of the host material and the light emitting material. The light emitting material may be a fluorescent light emitting material or a phosphorescent light emitting material, and the dopant may be one type or two or more types. The host material is preferably a charge transport material. The host material may be one kind or two or more kinds, and examples thereof include a configuration in which an electron transporting host material and a hole transporting host material are mixed. Furthermore, the light emitting layer may include a material that does not have charge transporting properties and does not emit light. Further, the light emitting layer may be a single layer or two or more layers, and each layer may emit light in different emission colors.

  Examples of the fluorescent light-emitting material include, for example, benzoxazole derivatives, benzimidazole derivatives, benzothiazole derivatives, styrylbenzene derivatives, polyphenyl derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, naphthalimide derivatives, coumarin derivatives, condensed aromatics. Compound, perinone derivative, oxadiazole derivative, oxazine derivative, aldazine derivative, pyralidine derivative, cyclopentadiene derivative, bisstyrylanthracene derivative, quinacridone derivative, pyrrolopyridine derivative, thiadiazolopyridine derivative, cyclopentadiene derivative, styrylamine derivative, di Typical examples include ketopyrrolopyrrole derivatives, aromatic dimethylidin compounds, metal complexes of 8-quinolinol derivatives and metal complexes of pyromethene derivatives. Various metal complexes are, polythiophene, polyphenylene, polyphenylene vinylene polymer compounds include compounds such as organic silane derivatives.

Examples of the phosphorescent material include a complex containing a transition metal atom or a lanthanoid atom.
Although it does not specifically limit as said transition metal atom, Preferably, ruthenium, rhodium, palladium, tungsten, rhenium, osmium, iridium, and platinum are mentioned, More preferably, they are rhenium, iridium, and platinum.
Examples of the lanthanoid atom include lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. Among these lanthanoid atoms, neodymium, europium, and gadolinium are preferable.

  Examples of the ligand of the complex include G. Wilkinson et al., Comprehensive Coordination Chemistry, Pergamon Press, 1987, H. Yersin, “Photochemistry and Photophysics of Coordination Compounds,” Springer-Verlag, 1987, Akio Yamamoto. Examples of the ligands described in the book “Organic Metal Chemistry-Fundamentals and Applications-” published in 1982 by Hankabosha.

  Examples of the host material contained in the light emitting layer include those having a carbazole skeleton, those having a diarylamine skeleton, those having a pyridine skeleton, those having a pyrazine skeleton, those having a triazine skeleton, and those having an arylsilane skeleton. And materials exemplified in the sections of a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer described later.

-Hole injection layer, hole transport layer-
The hole injection layer and the hole transport layer are layers having a function of receiving holes from the anode or the anode side and transporting them to the cathode side. Specifically, the hole injection layer and the hole transport layer are carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamines. Derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidin compounds, porphyrin compounds, organosilane derivatives, carbon , Etc. are preferable.

-Electron injection layer, electron transport layer-
The electron injection layer and the electron transport layer are layers having a function of receiving electrons from the cathode or the cathode side and transporting them to the anode side. Specifically, the electron injection layer and the electron transport layer are triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, Carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, aromatic tetracarboxylic anhydrides such as naphthalene and perylene, phthalocyanine derivatives, metal complexes of 8-quinolinol derivatives, metal phthalocyanines, benzoxazoles and benzothiazoles as ligands It is preferably a layer containing various metal complexes typified by metal complexes, organosilane derivatives, and the like.

-Hole blocking layer-
The hole blocking layer is a layer having a function of preventing holes transported from the anode side to the light emitting layer from passing through to the cathode side. In the present invention, a hole blocking layer can be provided as an organic compound layer adjacent to the light emitting layer on the cathode side. In addition, the electron transport layer / electron injection layer may also function as a hole blocking layer.
Examples of the organic compound constituting the hole blocking layer include aluminum complexes such as BAlq, triazole derivatives, phenanthroline derivatives such as BCP, and the like.
In addition, a layer having a function of preventing electrons transported from the cathode side to the light emitting layer from passing through to the anode side can be provided at a position adjacent to the light emitting layer on the anode side. The hole transport layer / hole injection layer may also serve this function.

TFT display element The gas barrier film in the present invention can be used as a substrate for a thin film transistor (TFT) image display element. Examples of the method for producing the TFT array include the method described in JP-T-10-512104. Further, this substrate may have a color filter for color display. The color filter may be produced using any method, but it is preferable to use a photolithography technique.
Moreover, the organic EL element in this specification means an organic electroluminescence element.

  The present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

Example 1
(Preparation of organic / inorganic laminated gas barrier film)
As a base film, a polyethylene naphthalate (PEN) film (thickness: 200 μm) commercially available from Teijin DuPont under the trade name Teonex Q65FA was used. A gas barrier layer composed of such an organic layer and an inorganic layer was applied.

Using an organic / inorganic laminated film forming apparatus (Guardian 200) manufactured by Vitex Systems, an ultraviolet-curing polymer precursor (manufactured by Vitex Systems, BRS-0101) is flash-deposited on the smooth surface side of the base film. Then, ultraviolet rays were irradiated for polymerization to form an organic layer. The film thickness was 1.1 μm. The irradiation energy of ultraviolet rays for polymerization was ² J / cm ² .
Here, Guardian 200 is an apparatus capable of producing an organic / inorganic laminated gas barrier layer. Since the organic layer and the inorganic layer are formed in a vacuum consistently, they are not released to the atmosphere until the gas barrier layer is completed.
Subsequently, an inorganic layer was formed on the organic layer using an organic / inorganic laminated film forming apparatus (Guardian 200) without removing the base film from the vacuum. The inorganic layer is an aluminum oxide film formed by a reactive sputtering method (reactive gas is oxygen) using a direct current pulse targeting aluminum. The film thickness of the obtained inorganic layer was 40 nm.
By repeating the above operation, an organic-inorganic laminated gas barrier film was produced by alternately laminating four organic layers and three inorganic layers in the order of the organic layer and the inorganic layer from the side close to the base film.

(Production of organic EL element)
A hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer are sequentially provided on the ITO substrate subjected to the oxygen plasma treatment, and the cathode is patterned with a shadow mask. Provided. Each layer was provided by resistance heating vacuum deposition.
The oxygen plasma conditions and the structure of each layer are as follows.
Oxygen plasma conditions: O ₂ flow rate = 10 sccm, RF power 200 W, treatment time 1 minute.
Hole injection layer: 4,4 ′, 4 ″ -tris (2-naphthylphenylamino) triphenylamine (abbreviated as 2-TNATA), thickness 140 nm.
Hole transport layer: N, N′-dinaphthyl-N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine (abbreviated as α-NPD), thickness 10 nm.
Light-emitting layer: 4,4′-bis- (9-carbazolyl) -biphenyl (abbreviated as CBP) and fac-tris (2-phenylpyridinato-N, C2 ′) iridium (III) (Ir (ppy) ₃ Abbreviated to CBP), and a thickness of 20 nm.
Hole blocking layer: bis (2-methyl-8-hydroxyquinolinato) -4-phenylphenolato aluminum (III) (abbreviated as BAlq), thickness 10 nm.
Electron transport layer: tris (8-hydroxyquinolinato) aluminum (abbreviated as Alq ₃ ), thickness 20 nm.
Electron injection layer: LiF, thickness 1 nm.
Cathode (upper electrode): Al, thickness 200 nm. The crossing area (light emitting part area) between the ITO electrode and the Al electrode is 2 mm × 2 mm.
Protective film: SiN _x film, thickness 2 μm. The film was formed by plasma CVD (PECVD).

(Sealing of organic EL elements with organic / inorganic laminated gas barrier films)
On the organic EL element produced above, an organic / inorganic laminated gas barrier film was bonded using an adhesive layer composition having the composition shown in Table 1.
The organic EL device sealed with the obtained organic / inorganic laminate type gas barrier film was evaluated for changes with time and changes with time in the luminous environment, and are shown in Table 1 below.

(Change over time in a humidity environment)
It was allowed to stand for 500 hours under conditions of a temperature of 40 ° C. and a relative humidity of 90%, and the occurrence of dark spots was evaluated. Evaluation was performed in three stages of A, B, and C. B and above are practical levels.

(Change in luminous efficiency over time)
Regarding the change in luminous efficiency over time, the organic EL element was set in an emission spectrum measurement system (ELS 1500) manufactured by Shimadzu Corporation, and the luminous efficiency (external quantum efficiency) at a luminance of 100 Cd / m ² was measured. The organic EL device was allowed to stand at room temperature and normal pressure for 500 hours, and then the luminous efficiency was measured again to examine the change in luminous efficiency. Evaluation was performed in three stages of A, B, C, D, and E. D or higher is a practical level.

Effect on change with time in humidity environment From Examples 4 and 5, 5% (adhesion) was obtained by adding calcium oxide as a hygroscopic agent at a ratio of 10% of the adhesive layer (adhesive: hygroscopic agent = 9: 1). It was found to be better than the case of adding the agent: hygroscopic agent = 19: 1).

 In addition, the examples except that the base film was changed from a polyethylene naphthalate (PEN) film to a biaxially stretched polyethylene terephthalate (PET) film (thickness: 100 μm) marketed by Toray Industries under the trade name Lumirror T60. As a result, the same effect as in Example 1 was obtained.

  By the sealing method of the present invention, it is possible to isolate the device from water and oxygen without deteriorating the quality of the environmentally sensitive device. In addition, in the present invention, since the generation of dark spots can be suppressed, the life of the environment sensitive device can be improved. Furthermore, when the technique of the present invention is used for the organic EL element, the deterioration in luminous efficiency with time is suppressed.

FIG. 1 shows an example of a schematic view of an image display element sealed with a gas barrier film in the present invention. FIG. 2 is a schematic view of the image display element portion of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image display element 2, 3 contact bonding layer 4 Organic-inorganic laminated type gas barrier film 11 Board | substrate 12 Display part

Claims (12)

Environmental sensitivity characterized in that the environmental sensitivity device is sealed by a gas barrier film having a barrier layer including an organic region and an inorganic region through an adhesive layer including a group 2 oxide-based hygroscopic agent and / or an oxygen scavenger. Device sealing method. An environmentally sensitive device is sealed by a gas barrier film having a barrier layer including an organic region and an inorganic region through an adhesive layer including a group 2 oxide-based hygroscopic agent and an oxygen scavenger. Sealing method. The method for sealing an environmentally sensitive device according to claim 1, wherein the barrier layer including the organic region and the inorganic region has at least one organic layer and at least one inorganic layer. The method for sealing an environment-sensitive device according to claim 1, wherein the oxygen scavenger is an iron-based oxygen scavenger. The environment-sensitive device is an image display element having a display portion and a non-display portion, including an oxygen scavenger in an adhesive layer provided on the non-display portion, and provided on the display portion. The method for sealing an environmentally sensitive device according to claim 1, wherein the adhesive layer does not contain an oxygen scavenger. The environmentally sensitive device sealing method according to any one of claims 1 to 5, wherein the group 2 oxide-based moisture absorbent is calcium oxide or strontium oxide. The method for sealing an environment-sensitive device according to claim 1, wherein the environment-sensitive device is an organic EL element. An image display element sealed with a gas barrier film through an adhesive layer,
The gas barrier film has an organic region and an inorganic region,
The image display element includes a display portion and a non-display portion, an adhesive layer provided on the display portion includes an oxygen scavenger and a Group 2 oxide-based moisture absorbent, and is provided on the non-display portion. An image display element that does not contain an oxygen scavenger in the adhesive layer formed. The image display element according to claim 8, wherein the oxygen scavenger is iron-based. The image display element according to claim 8 or 9, wherein the adhesive layer contains 80 to 90% by weight of an adhesive and 10 to 20% by weight of a Group 2 oxide-based moisture absorbent. The image display element according to any one of claims 8 to 10, wherein the group 2 oxide-based hygroscopic agent is calcium oxide or strontium oxide. The image display element according to claim 8, wherein the image display element is an organic EL element.

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