KR101428868B1 - Adhesive film - Google Patents

Abstract

Embodiments of the present invention relate to an adhesive film used for encapsulating or encapsulating an organic electronic device. An exemplary adhesive film is capable of effectively preventing moisture from penetrating into the encapsulating or encapsulating structure of the organic electronic device after encapsulating or encapsulating the organic electronic device, but does not damage the organic electronic device in the encapsulating or encapsulating process , So that the process can be efficiently performed under mild conditions.

Description

Adhesive film

Embodiments of the present invention relate to an adhesive film and a method of encapsulating an organic electronic device using the same.

Organic electronic devices (OEDs) refer to articles or devices that contain one or more layers of organic materials that generate alternating charges using holes and electrons. Examples of the organic electronic device include a photovoltaic device, an organic light emitting diode (OLED), a rectifier, and a transmitter.

The organic light emitting diode (OLED) has a lower power consumption and a faster response speed than conventional light sources, and is advantageous for thinning display devices or lighting. In addition, organic light emitting diodes are expected to be applied in various fields covering various portable devices, monitors, notebooks, and televisions because of their excellent space utilization.

In the conventional organic light emitting device, in order to seal the organic light emitting element formed on the substrate made of glass or polymer film, a part of the glass or metal can, which has been processed into a cap shape so as to have a groove with a getter or a moisture absorbing agent, . In such a structure, a cavity or protrusion of a certain depth is required to mount the getter or the moisture absorbent. In addition, since the glass can be easily broken by mechanical impact, the overall impact resistance of the device is very low. Further, it is difficult to secure the workability in response to the enlargement of the apparatus. In the organic light emitting device having the conventional structure, heat is not easily emitted due to the presence of a cavity, so heat generated during the display driving is concentrated at the center, which causes deterioration of the device at the time of enlarging the device. It is impossible to increase the total emission.

Patent Document 1: U.S. Patent No. 6,226,890 Patent Document 2: U.S. Patent No. 6,808,828 Patent Document 3: Japanese Patent Application Laid-Open No. 2000-145627 Patent Document 4: JP-A-2001-252505

Embodiments of the present invention provide an adhesive film, an organic electronic device using the same, and a method of encapsulating an organic electronic device.

Embodiments of the present invention are directed to adhesive films. An exemplary adhesive film may include a multi-layered adhesive layer, for example, a first adhesive layer that includes a hygroscopic filler and a second adhesive layer that does not include a hygroscopic filler.

In one example, the adhesive film can be used to encapsulate or encapsulate an organic electronic device (OED). In one example, the adhesive film may be bonded to the front surface of the organic electronic device without a gap to seal or encapsulate the organic electronic device. The adhesive layer of the adhesive film directly adhered to the organic electronic device is a second adhesive layer, and when the organic electronic device is encapsulated or encapsulated, the first adhesive layer is an adhesive layer that is not in contact with the organic electronic device.

The term " organic electronic device " means an article or an element that includes at least one organic material layer that generates alternating charges using holes and electrons between a pair of electrodes facing each other. Specific examples thereof include a photovoltaic device but are not limited to, photovoltaic devices, rectifiers, transmitters, and organic light emitting diodes (OLEDs). In one example, the organic electronic device may be an organic light emitting diode.

Other embodiments of the invention relate to organic electronic devices. Exemplary organic electronic devices may include organic electronic devices encapsulated by the adhesive film. In one example, the second adhesive layer in the adhesive film, that is, the adhesive layer not including the hygroscopic filler may be present attached to the front surface of the organic electronic device. In addition, the adhesive layer including the first adhesive layer, i.e., the hygroscopic filler may be present at a position not in contact with the organic electronic device.

According to still another embodiment of the present invention, there is provided a method of manufacturing an organic electronic device, including the steps of: applying the adhesive film to a substrate including an organic electronic device formed on a top thereof, wherein a second adhesive layer of the adhesive film is attached to the front surface of the organic electronic device; And a step of curing the adhesive film.

The adhesive film according to embodiments of the present invention can be used, for example, for encapsulating or encapsulating organic electronic devices.

1 to 3 are views showing an exemplary adhesive film.
4 is a conceptual diagram showing a calcium test for evaluating the moisture barrier property of the adhesive film.
Figures 5 and 6 are views showing another exemplary adhesive film.
7 is a diagram illustrating an exemplary organic electronic device.
8 is an optical microscope photograph taken after being left in a temperature and humidity chamber of an organic light-emitting panel manufactured using the adhesive film prepared in Comparative Example 3 at a temperature of 85 ° C and an environment of 85% RH for 1000 hours.
9 is an optical microscope photograph of a case where the adhesion process is simulated using the adhesive film prepared in Comparative Example 4. FIG.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known general functions or configurations will be omitted. It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. And the scope of the present invention is not limited by the thickness, size, ratio or the like shown in the drawings.

The adhesive film according to the embodiments of the present invention is used for encapsulating or encapsulating an organic electronic device. The term " organic electronic device " means an article or an element having a structure including at least one organic material layer that generates alternating charges using holes and electrons between a pair of electrodes facing each other, But are not limited to, photovoltaic devices, rectifiers, transmitters, and organic light emitting diodes (OLEDs). In one example of the present invention, the organic electronic device may be an OLED.

An exemplary adhesive film may be a multi-layer structure including at least two adhesive layers, and at least one of the adhesive layers of at least two layers may include a hygroscopic filler, and at least one of the adhesive layers does not include a hygroscopic filler .

That is, in one example, the adhesive film may include a first adhesive layer including a hygroscopic filler and a second adhesive layer not including a hygroscopic filler.

In one example, the adhesive film can be used to encapsulate or encapsulate the organic electronic device without gaps, that is, without being spaced directly on the front surface of the organic electronic device. At this time, the second adhesive layer that does not include the hygroscopic filler of the adhesive film can be directly contacted to the organic electronic device, and the first adhesive layer including the hygroscopic filler when encapsulating or encapsulating the organic electronic device, As shown in Fig.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an exemplary adhesive film. Fig. 1, the adhesive film 1 includes at least a first adhesive layer 11 and a second adhesive layer 12, and in one example, the first and second adhesive layers 11 and 12 May be present in a state in which they are stacked one after the other. At this time, the ratio (T1 / T2) of the thickness of the first adhesive layer 11 (T1 in FIG. 1) to the thickness of the second adhesive layer 12 (T2 in FIG. 1) may be 1 to 10. In various embodiments, the upper limit of the ratio T1 / T2 may be about 50, 45, 40, 35, 30, 25, 20, 15, 10, 5 or 3. The lower limit of the ratio T1 / T2 may be, for example, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0 or 4.5.

The ratio of the thickness of the first adhesive layer to the thickness of the second adhesive layer (T1 / T2) may be adjusted as described above, for example, when the adhesive film is used for encapsulation or encapsulation of organic electronic devices, after encapsulation or encapsulation It is possible to effectively prevent moisture from penetrating into the encapsulating or encapsulating structure, and to provide a sealing or encapsulating structure having excellent durability and long life. In addition, the encapsulation or encapsulation process can be efficiently performed under mild conditions in the range of the ratio (T1 / T2).

In embodiments of the present invention, the first adhesive layer may have a thickness of 5 占 퐉 or more, 10 占 퐉 or more, 15 占 퐉 or more, 20 占 퐉 or more, 25 占 퐉 or more, or 30 占 퐉 or more. The upper limit of the thickness of the first adhesive layer is not particularly limited, since the thicker the first adhesive layer, the more the moisture permeating into the element after encapsulation or encapsulation can be efficiently adsorbed or removed. However, if the thickness of the first adhesive layer is excessively thick, the adhesion of the adhesive film may be deteriorated during the encapsulation or encapsulation, so that the upper limit of the appropriate thickness can be determined in consideration of this. In one example, the upper limit of the thickness may be, for example, 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, 30 μm or less, have.

The thickness of the second adhesive layer may be equal to or greater than the maximum average diameter of the hygroscopic filler included in the first adhesive layer. If the thickness of the second adhesive layer is too small, it may cause damage to the organic electronic device in the encapsulation or encapsulation process. Therefore, an appropriate thickness can be selected in consideration of this. The average diameter of the hygroscopic filler is usually about 3 탆 to 4 탆. Accordingly, the second adhesive layer may have a thickness of at least 3 mu m, at least 4 mu m, at least 5 mu m, at least 6 mu m, or at least 7 mu m. The upper limit of the thickness of the second adhesive layer may be, for example, 20 占 퐉 or less, 15 占 퐉 or less, or 10 占 퐉 or less.

As described above, the thickness of the entire adhesive layer of the adhesive film including at least the first and second adhesive layers is, for example, 8 占 퐉 or more, 10 占 퐉 or more, 15 占 퐉 or more, 20 占 퐉 or more, 25 占 퐉 or more or 30 占 퐉 or more . The upper limit of the total thickness is, for example, 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, Mu m or less. If the thickness of the entire adhesive layer is less than 8 mu m, it can not compensate for the physical damage caused by the hygroscopic filler or other particles. If the thickness of the entire adhesive layer exceeds 100 mu m, In particular, when the adhesive is cemented, the degree of detachment of the adhesive to the outside may be increased, which may cause a problem of adhesion.

The adhesive film may further include another adhesive layer as long as it includes at least the first and second adhesive layers.

In other embodiments of the present invention, the adhesive film may further include at least one or more adhesive layers that include a hygroscopic filler, or at least one or more adhesive layers that do not include a hygroscopic filler. That is, the adhesive layer may further include at least one adhesive layer including the hygroscopic filler, and may further include at least one adhesive layer not including the hygroscopic filler, or both of them may be further included .

In one example, the adhesive film 2 has a structure in which the second adhesive layer 12, the first adhesive layer 11, and the third adhesive layer 21 are sequentially stacked, as shown in FIG. 2 Of an adhesive layer. In such a case, the third adhesive layer 21 may be an adhesive layer not containing a hygroscopic filler.

3, the second adhesive layer 12, the first adhesive layer 11, the third adhesive layer 31 and the fourth adhesive layer 32 ) May be sequentially stacked. In this case, the third adhesive layer 31 may be an adhesive layer not including a hygroscopic filler, and the fourth adhesive layer 32 may be an adhesive layer including a hygroscopic filler, and vice versa.

The adhesive film may be formed in various other structures in addition to the structures of Figs. In this case, the ratio (T3 / T4) of the total thickness T4 of the adhesive layers including the hygroscopic filler to the total thickness T3 of the adhesive layers not including the hygroscopic filler satisfies the thickness ratio T1 / T2 .

That is, if the adhesive film further includes another adhesive layer including a hygroscopic filler in addition to the first adhesive layer, for example, the thickness of the first adhesive layer or the thickness of the first adhesive layer itself May be a total thickness of the thickness of the adhesive layer including the hygroscopic filler.

In one example, when the adhesive film has a multi-layer structure of two or more layers, an adhesive layer not including the hygroscopic filler may be disposed on the lowermost portion of the entire adhesive layer. In another example, when the adhesive film has a multilayer structure of three or more layers, adhesive layers that do not include the hygroscopic filler may be disposed on the lowermost and uppermost portions of the entire adhesive layer. In another example, when the adhesive film has a multilayer structure of four or more layers, an adhesive layer including a hygroscopic filler and an adhesive layer not including a hygroscopic filler may be formed so as to be laminated in order of intersection.

The specific kind of the adhesive composition for forming the adhesive layer other than the first or second adhesive layer or the first and second adhesive layers is not particularly limited.

In one example, the adhesive layer can be formed using a curable hot melt adhesive composition comprising at least one type of curable resin. As used herein, the term "curable hot melt adhesive composition" refers to a composition that maintains a solid or semi-solid state at room temperature, melts when heated and exhibits adhesiveness, and after curing, Which may be an adhesive capable of firmly fixing an object.

For example, the adhesive film according to the embodiments of the present invention may have a viscosity at room temperature of 10 ⁶ Pa · s or more or 10 ⁷ Pa · s or more. The term " ambient temperature " means a natural, non-warming or non-warming temperature, and may mean, for example, a temperature of from about 15 캜 to 35 캜, from about 20 캜 to 25 캜 or about 25 캜. The viscosity can be measured using an Advanced Rheological Expansion System (ARES). The viscosity of the curable hot melt adhesive is controlled within the above range to prevent physical or chemical damage to the device due to resin curing or the like during encapsulation or encapsulation, Enclosure is possible.

By the adhesive film, the adhesive layer of the specific adhesive film is, considering the maintaining state of a solid or semi-solid at room temperature, the upper limit of the viscosity is not particularly limited, for example, fairness, etc., from about 10 ⁹ Pa · s or less.

The moisture barrier properties of the adhesive film can be evaluated using, for example, a calcium test. Since calcium reacts easily with water and changes its color easily, the moisture barrier performance is better as the calcium is not damaged when exposed to high temperature and high humidity conditions for the same time. The ideal value in the calcium test is based on standing at 6 mm in 1000 hours at high temperature and high humidity (85 캜, 85% relative humidity) conditions. For example, as shown in FIG. 4, in the calcium test, an adhesive film is adhered to a top plate glass having a size of 17 × 17 mm, and then calcium is deposited on the bottom plate glass to a size of 5 × 5 mm. The glass is cemented. The cured sample may be thermally cured and then confirmed by a microscope to confirm the moisture permeation length with time, but the present invention is not limited thereto.

Generally, When the adhesive film is laminated on the adherend under the condition of the temperature range of 50 to 100 ° C in an uncured state, the adhesive layer may be laminated on the adhesive layer at a temperature of lamination (adhesion) The degree of detachment of the adhesive may be less than 1 mm from its original position. The viscosity difference between the first adhesive layer and the second adhesive layer in the uncured state in the temperature range of 30 to 130 占 폚 may be 100 Pa · s or less, or 70 Pa · s or less, 50 Pa · s or less, 20 Pa · s or less, and 10 Pa · s or less. The viscosity of the upper or lower layer in the first adhesive layer and the second adhesive layer may be large or small and ideally the viscosity difference between each sub-adhesive layer may be 0 Pa · s.

When the viscosity difference between the first adhesive layer and the second adhesive layer in the uncured state in the temperature range of 30 ° C to 130 ° C is 100 Pa · s or less or preferably 50 Pa · s or less in the uncured state, The reliability can be secured because the difference in the degree of flow or the degree of deviation of the layer is small. As described above, when the viscosity difference between the first adhesive layer and the second adhesive layer in the uncured state is in the range of 30 ° C to 130 ° C, the difference in the degree of flow or the degree of deviation of each sub- May be 0 mu m to 300 mu m. At this time, the general lamination process is to heat-bond the adhesive film to the adherend at a temperature range of 50 ° C to 100 ° C, a variable pressure range, but is not limited thereto. For example, the lamination may be performed at a pressure of 0.05 to 5 MPa. By controlling the viscosity in the heating range of the adhesive layer in the uncured state as described above, the flowability of the adhesive can be controlled to provide reliability in application to the process.

The viscosities of the first adhesive layer and the second adhesive layer can be adjusted by varying the constituent components, the content ratio of the constituent components, the content of the additives, the hygroscopicity or the kind or the particle size of the filler, and the production conditions of the adhesive film.

The specific kind of the curable resin that can be used in the embodiments of the present invention is not particularly limited, and for example, various thermosetting, photo-curing resins or dual curing resins known in the art can be used. The term " thermosetting resin " means a resin that can be cured through an appropriate heat application or aging process, the term " photo-curing resin " means a resin that can be cured by irradiation with electromagnetic waves, Quot; dual curable resin " means a resin that has both the properties of a thermosetting resin and a photo-curable resin and can be cured by irradiation of electromagnetic waves and application of heat. In the above, the category of electromagnetic waves includes not only microwaves, infrared rays (IR), ultraviolet rays (UV), X-rays and gamma rays but also alpha-particle beams, proton beams, a particle beam such as a neutron beam and an electron beam, and the like. One example of the photocurable resin is a cationic photocurable resin. The cationic photocurable resin means a resin which can be cured by cationic polymerization or cationic curing reaction induced by irradiation of an electromagnetic wave.

The specific kind of the curable resin is not particularly limited as long as it has the above-mentioned characteristics. For example, it may include one or more thermosetting functional groups such as a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group or an amide group, which may be cured to exhibit an adhesive property, or an epoxy group, a resin containing at least one functional group capable of being cured by irradiation of an electromagnetic wave such as a cyclic ether group, a sulfide group, an acetal group or a lactone group. Specific examples of the resin include acrylic resins, polyester resins, isocyanate resins, epoxy resins, and the like, but the present invention is not limited thereto.

As the curable resin, aromatic or aliphatic; Or a linear or branched epoxy resin may be used. In one example, an epoxy resin having an epoxy equivalent of 180 g / eq to 1,000 g / eq, which contains two or more functional groups, can be used. By using an epoxy resin having an epoxy equivalent in the above range, properties such as adhesion performance and glass transition temperature of the cured product can be effectively maintained. Examples of such an epoxy resin include cresol novolak epoxy resin, bisphenol A epoxy resin, bisphenol A novolak epoxy resin, phenol novolak epoxy resin, tetrafunctional epoxy resin, biphenyl type epoxy resin, triphenol methane type epoxy A resin, an alkyl-modified triphenolmethane epoxy resin, a naphthalene-type epoxy resin, a dicyclopentadiene-type epoxy resin, or a dicyclopentadiene-modified phenol-type epoxy resin.

In one example, an epoxy resin containing a cyclic structure in the molecular structure may be used as the curable resin, and for example, an epoxy resin containing an aromatic group such as a phenyl group may be used. When the epoxy resin contains an aromatic group, the cured product has excellent thermal and chemical stability and exhibits a low moisture absorption amount, thereby improving the reliability of the organic electronic element encapsulation structure. Specific examples of the aromatic group-containing epoxy resin include biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene modified phenol type epoxy resin, cresol type epoxy resin, bisphenol type epoxy resin, Based epoxy resin, a polyfunctional epoxy resin, a phenol novolak epoxy resin, a triphenol methane-type epoxy resin, and an alkyl-modified triphenol methane epoxy resin, but the present invention is not limited thereto.

In another example, as the epoxy resin, a silane-modified epoxy resin, for example, a silane-modified epoxy resin having an aromatic group, can be used. When an epoxy resin having a silyl group modified by silane is used, it is possible to maximize the adhesion of the organic electronic device to the glass substrate or the inorganic material of the substrate, and to improve the moisture barrier property, durability and reliability . The specific kind of the epoxy resin is not particularly limited and various kinds of epoxy resins known in the art can be used as long as the above-mentioned properties such as the moisture permeability are satisfied.

The adhesive layer including the hygroscopic filler such as the first adhesive layer includes a hygroscopic filler in addition to the curable resin. The term " hygroscopic filler " can be used generically to refer to components capable of adsorbing or removing moisture or moisture introduced from the outside through moisture and chemical reaction, and is also referred to as a water-reactive adsorbent.

The hygroscopic filler chemically reacts with moisture, moisture or oxygen introduced into the adhesive layer to absorb moisture or moisture. Specific examples of the hygroscopic filler that can be used in the embodiments of the present invention are not particularly limited and include metal powders such as alumina, metal oxides, organic metal oxides, metal salts, or phosphorus pentoxide (P ₂ O ₅ ) One or a mixture of two or more.

Specific examples of the metal oxide include lithium oxide (Li ₂ O), sodium oxide (Na ₂ O), barium oxide (BaO), calcium oxide (CaO) and magnesium oxide (MgO) Examples include lithium sulfate (Li ₂ SO _4), sodium sulfate (Na ₂ SO _4), calcium sulfate (CaSO _4), magnesium sulfate (MgSO _4), cobalt sulfate (CoSO _4), sulfate, gallium (Ga ₂ (SO _{4) 3),} titanium sulfate (Ti (SO _{4) 2)} or nickel sulfate (a sulfate such as NiSO _4), calcium chloride (CaCl _2), magnesium chloride (MgCl _2), strontium chloride (SrCl _2), chloride, yttrium (YCl ₃₎ , Cobalt chloride (CuCl ₂ ), cesium fluoride (CsF), tantalum fluoride (TaF ₅ ), niobium fluoride (NbF ₅ ), lithium bromide (LiBr), calcium bromide (CaBr ₂ ), cesium bromide (CeBr ₃ ) (SeBr _4), vanadium bromide (VBr _3), a metal halide such as magnesium bromide (MgBr _2), barium iodide (BaI _2), or magnesium iodide (MgI _2); Or metal chlorates such as barium perchlorate (Ba (ClO ₄ ) ₂ ) or magnesium perchlorate (Mg (ClO ₄ ) ₂ ), and the like.

In embodiments of the present invention, a hygroscopic filler such as the metal oxide may be incorporated into the composition in a properly processed state. For example, depending on the type of the organic electronic device to which the adhesive film is applied, the entire adhesive layer may be a thin film having a thickness of 30 μm or less. In this case, a crushing process of the hygroscopic filler may be required. For grinding the hygroscopic filler, a process such as a three-roll mill, a bead mill or a ball mill may be used. In addition, when the adhesive film is used in a top emission type organic electronic device or the like, the permeability of the adhesive layer itself becomes very important, and therefore the size of the hygroscopic filler needs to be small. Therefore, a grinding process may be required even in such a use.

The adhesive layer may contain the hygroscopic filler in an amount of 5 parts by weight to 50 parts by weight, or 10 parts by weight to 30 parts by weight, based on 100 parts by weight of the curable resin. By controlling the content of the hygroscopic filler in the above range, it is possible to maximize the moisture barrier property within a range that does not damage the organic electronic device.

In the present specification, unless otherwise specified, the unit " weight part " means a weight ratio between the respective components.

It is preferable that the hygroscopic filler is uniformly dispersed in the adhesive layer of the adhesive film.

The adhesive layer of the adhesive film according to the embodiments of the present invention may include a non-hygroscopic filler, for example, an inorganic filler, irrespective of whether the hygroscopic filler is contained or not. The (non-hygroscopic) filler can increase permeation of water or moisture penetrating into the sealing structure to suppress penetration thereof, and maximize the barrier against moisture and moisture through interaction with the matrix structure of the curable resin The durability such as mechanical strength of the adhesive film can be improved.

Specific examples of the (non-hygroscopic) filler that can be used in the embodiments of the present invention are not particularly limited and include clay, talc, silica, barium sulfate, aluminum hydroxide, calcium carbonate, magnesium carbonate, zeolite, Titania, montmorillonite, and the like, or a mixture of two or more thereof.

Further, in order to increase the bonding efficiency between the filler and the curable resin, the filler may be a product surface-treated with an organic material, or may further be added with a coupling agent.

The adhesive layer may include 3 to 50 parts by weight, or 5 to 30 parts by weight of filler based on 100 parts by weight of the curable resin. The filler content is controlled to 3 parts by weight or more to provide a cured product having excellent moisture or moisture barrier properties and mechanical properties. By controlling the content of the filler to 50 parts by weight or less, it is possible to provide a cured product which can be produced in the form of a film and which exhibits adhesive properties even when formed into a thin film.

The adhesive composition may also contain a curing agent capable of reacting with the curable resin to form a matrix such as a crosslinked structure or the like, or an initiator capable of initiating the curing reaction of the resin, for example, a cationic photopolymerization initiator And the like.

The specific kind of the curing agent is not particularly limited and may be appropriately selected depending on the kind of the functional group contained in the curable resin or the resin. For example, when an epoxy resin is used as the curable resin, a general curing agent for epoxy resin known in this field as a curing agent can be used. Specific examples thereof include various amine compounds, imidazole compounds, phenol compounds, A compound or an acid anhydride-based compound, and the like, but not limited thereto.

The content of the curing agent contained in the adhesive composition may be selected depending on the composition of the composition and may be, for example, 1 part by weight to 20 parts by weight or 1 part by weight to 10 parts by weight per 100 parts by weight of the curable resin . However, the above content is only one example. That is, the content of the curing agent can be changed according to the type and content of the curable resin or the functional group, or the matrix structure or crosslinking density to be implemented.

The kind of the initiator, for example, the cation polymerization initiator is not particularly limited, and for example, a known cation polymerization initiator such as an aromatic diazonium salt, an aromatic iodo aluminum salt, an aromatic sulfonium salt or an iron- It is preferable to use an aromatic sulfonium salt, but it is not limited thereto.

In the above case, the content of the initiator may be, for example, 0.01 to 10 parts by weight or 0.1 to 3 parts by weight based on 100 parts by weight of the curable resin. If the content of the initiator is too small, there is a fear that sufficient curing will not proceed. If the content of the initiator is excessively large, the content of the ionic substance after curing will increase and the durability of the adhesive will deteriorate. , Which is disadvantageous from the viewpoint of optical durability, and corrosion may occur depending on the base material. Therefore, an appropriate content range can be selected in consideration of this point.

The adhesive composition may further include a binder resin. The binder resin may serve to improve moldability, for example, when the composition is molded into a film or a sheet. It can also serve as a high-temperature viscosity modifier that stabilizes flowability during the hot-melt process.

The kind of the binder resin is not particularly limited as long as it is compatible with other components such as a curable resin. Specific examples of the binder resin include phenoxy resins, acrylate resins, high molecular weight epoxy resins having a weight average molecular weight of 20,000 or more, ultrahigh molecular weight epoxy resins, high-polarity functional group-containing rubbers, and high- Reactive rubber, and the like, but is not limited thereto.

When the binder resin is contained in the adhesive composition, the content thereof is not particularly limited as it can be controlled according to the desired physical properties. For example, the binder resin may be contained in an amount of about 10 to 200 parts by weight, 20 to 150 parts by weight or less, or about 30 to 100 parts by weight, based on 100 parts by weight of the curable resin. The content of the binder resin is controlled to 10 to 200 parts by weight or less to effectively maintain compatibility with each component of the resin composition and also to serve as an adhesive. If the binder is too small, it may be difficult to adjust the mold releasing force because the resin may flow out from the resin due to low viscosity in the cementing process or the adhesive strength at room temperature may be high. Also, if the binder is too large, the adhesion may be poor. Therefore, by controlling the content of the binder resin, the viscosity of each layer can be controlled to reduce the difference, thereby ensuring optimum processability and physical properties.

The adhesive composition may further include additional fillers for enhancing the durability of the cured product within a range not affecting the desired effect; An additive such as a coupling agent, a plasticizer, a UV stabilizer and an antioxidant for improving mechanical strength and adhesion.

The method of forming the adhesive layer using the adhesive composition is not particularly limited. For example, the adhesive layer may be formed by selecting an appropriate adhesive composition according to whether or not the hygroscopic filler of each adhesive layer is included, coating the coating solution containing the composition, and then drying. The laminated structure of the adhesive layer can be formed by laminating the adhesive layer formed after the formation of the separate adhesive layer or by coating and drying another adhesive composition on the formed adhesive layer.

The coating of the adhesive composition hereinabove can be performed on a suitable process substrate, for example, a release surface of a releasable substrate.

The adhesive composition can be prepared in the form of a coating solution by selecting appropriate components as necessary and dissolving or dispersing them in an appropriate solvent. In this process, the content of the epoxy resin or the like contained in the coating liquid can be appropriately controlled in accordance with the desired moisture barrier property and film formability. Also, when the binder resin is included in the coating solution, the content of the binder resin may also be adjusted in consideration of film formability, impact resistance, and the like. If the amount of the solvent contained in the coating liquid is excessively increased in the above process, it may take a long time to dry, so that the amount of the solvent used may be minimized.

When a filler or the like is contained in the coating liquid, a ball mill, a bead mill, a three roll, or a high-speed pulverizer may be used alone or in combination with a ball mill, It can also be used. Examples of materials for the balls and beads include glass, alumina, and zirconium, and balls and beads made of zirconium are preferable in terms of dispersibility of the particles.

The kind of the solvent used for preparing the coating liquid is not particularly limited. However, when the drying time of the solvent is excessively long or when it is necessary to dry at a high temperature, a problem may arise in terms of workability or durability of the adhesive film, and therefore a solvent having a volatilization temperature of 100 ° C or less may be used. In view of film formability and the like, a small amount of a solvent having a volatilization temperature in the above range may be mixed and used. Examples of the solvent include a solvent such as methyl ethyl ketone (MEK), acetone, toluene, dimethylformamide (DMF), methylcellosolve (MCS), tetrahydrofuran (THF), or N-methylpyrrolidone Or a mixture of two or more species.

The method of applying the above-mentioned coating liquid is not particularly limited, and known methods such as knife coat, roll coat, spray coat, gravure coat, curtain coat, comma coat or lip coat can be used without limitation.

The coated coating liquid may be dried to form an adhesive layer. In this process, the applied coating liquid can be heated to dry and remove the solvent to form an adhesive layer. The drying conditions are not particularly limited. For example, the drying may be performed at a temperature of 70 to 150 캜 for 1 to 10 minutes.

The adhesive film may have a structure in which the adhesive layer is formed on an appropriate base material film or release film (hereinafter may be referred to as " first film "). Fig. 5 exemplarily shows the case where the first and second adhesive layers 11 and 12 are formed on the base material or the release film 41. Fig.

The adhesive film may further include a base film or release film (hereinafter sometimes referred to as " second film ") formed on the adhesive layer. Fig. 6 exemplarily shows a case where the first and second adhesive layers 11 and 12 are formed between two sheets of base material or release films 41 and 51, respectively.

The adhesive film may include an adhesive layer formed on or between the base film or the release film, as shown in the figure. However, the adhesive film shown in the above drawings is only one example. The adhesive film may have, for example, a configuration in which only an adhesive layer that maintains a solid or semi-solid state at room temperature without a support substrate is included. In some cases, an adhesive layer may be provided on both sides of one base film or release film And may be formed in the form of a double-sided adhesive film.

The specific kind of the first film is not particularly limited. As the first film, for example, a general polymer film in this field can be used. Examples of the substrate or release film include a polyethylene terephthalate film, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polyvinyl chloride film, a polyurethane film, A vinyl acetate film, an ethylene-propylene copolymer film, an ethylene-ethyl acrylate copolymer film, an ethylene-methyl acrylate copolymer film, or a polyimide film. In addition, a suitable mold release treatment may be performed on one or both sides of the base film or the release film. Examples of the releasing agent used in the releasing treatment of the base film include an alkyd type, a silicone type, a fluorine type, an unsaturated ester type, a polyolefin type or a wax type. Among them, an alkyd type, a silicone type or a fluorine type releasing agent can be used from the viewpoint of heat resistance , But is not limited thereto.

The type of the second film (hereinafter also referred to as " cover film ") is not particularly limited. For example, as the second film, within the category exemplified in the first film described above, the same or a different kind as the first film can be used. In addition, the second film may also be subjected to appropriate mold release treatment.

The thickness of the base film or the release film is not particularly limited and may be appropriately selected depending on the application to which it is applied. For example, the thickness of the first film may be about 50 탆 to 500 탆 or about 100 탆 to 200 탆. If the thickness is less than 50 탆, automation in the panel manufacturing process is difficult, and if it exceeds 500 탆, the economical efficiency is low.

The thickness of the second film may be set, for example, to be the same as that of the first film. Further, the thickness of the second film may be set to be relatively thin in comparison with the first film in consideration of the processability and the like.

Other embodiments of the present invention also relate to organic electronic devices. Exemplary organic electronic devices may include organic electronic devices encapsulated by the adhesive film. In one example, the second adhesive layer in the adhesive film, that is, the adhesive layer not including the hygroscopic filler may be present attached to the front surface of the organic electronic device. In addition, the adhesive layer including the first adhesive layer, i.e., the hygroscopic filler may be present at a position not in contact with the organic electronic device.

In one example, the organic electronic device comprises: a substrate; And an organic electronic device formed on the substrate, and the organic electronic device may be encapsulated or encapsulated by the adhesive film. The organic electronic device may further include a cover substrate on the top.

The organic electronic device may be, for example, an organic light emitting diode.

The adhesive film has excellent moisture barrier properties, is excellent in optical characteristics, and can function as a structural adhesive for fixing and supporting the substrate and the cover substrate to provide the sealing layer.

In addition, the adhesive film exhibits excellent transparency and can be effectively applied to devices designed in a top emission mode or a bottom emission mode.

In addition, since the use of the adhesive film does not require the use of a getter and an etching material (metal can or glass can) as compared with the conventional process, there is an advantage that the manufacturing process can be simplified and the process cost can be reduced. The organic light emitting display device can be used regardless of the designing method such as a light emitting mode and the like, and has an advantage that excellent durability can be imparted to the finally produced organic light emitting display device.

7 is a view showing one example of the organic electronic device.

In order to manufacture an organic electronic device, for example, a transparent electrode is first formed on a glass or polymer film 61 used as a substrate by vacuum evaporation or sputtering, and an organic electronic device 63 is formed on the transparent electrode. , For example, an organic light emitting diode layer composed of a hole transporting layer, a light emitting layer, and an electron transporting layer is formed. Then, an electrode layer is further formed on the organic electronic device 63 formed. The sealing layer may be formed by laminating an adhesive film including the first adhesive layer 11 and the second adhesive layer 12 on the organic electronic device 63 of the substrate 61 that has undergone the above- .

The method of forming the sealing layer is not particularly limited. For example, a method may be employed in which the second adhesive layer of the above-mentioned adhesive film is applied to the front surface of the organic electronic device on the substrate including the organic electronic device formed thereon step; And a step of curing the adhesive film.

The step of applying the adhesive film to the organic electronic device can be performed by a hot roll laminate, a hot press, or a vacuum press method of an adhesive film, and is not particularly limited. The step of applying the adhesive film to the organic electronic device may be performed at a temperature of 50 to 100 DEG C and the curing step may be performed by heating to a temperature range of 70 to 110 DEG C or by irradiating UV have. It is also possible to add a step of attaching the adhesive film so as to be in contact with glass or metal which is an additional sealing material.

For example, a cover substrate (e.g., glass or polymer film) 62 onto which the above-described adhesive layer is previously transferred is laminated on the organic electronic device 63 formed on the substrate 61, followed by heating and pressing . In this step, for example, when the adhesive layer is transferred onto the cover substrate 62, the base film or the release film formed on the film is peeled off using the above-mentioned adhesive film, It may be transferred using a vacuum laminator or the like. In this process, when the adhesive is thermosetting, if the curing reaction is carried out over a certain range, the adhesion or adhesion of the sealing material may be reduced, so that the process temperature can be controlled to about 100 占 폚 or less and the process time to be controlled within 5 minutes. Then, the cover substrate 62 onto which the adhesive layer has been transferred is heat-pressed onto the organic electronic device. Even in this case, a vacuum press or a vacuum laminator can be used. In this process, the adhesive layer can be melted to exhibit adhesiveness.

Following the above process, an additional curing process may be performed on the adhesive film to form an encapsulating layer. This curing process can be carried out, for example, in a heating chamber or UV chamber. The heating condition or the irradiation condition of the electromagnetic wave during the main curing can be appropriately selected in consideration of the stability of the organic electronic device and the curing property of the resin.

However, the above-described manufacturing process is merely an aspect for manufacturing an organic electronic device, and the process order, process conditions and the like can be freely modified. For example, the order of the pressing and sealing steps may be changed to a method in which the adhesive film is first transferred to the organic electronic device 63 on the substrate 61, and then the cover substrate 62 is squeezed.

Hereinafter, the present invention will be described in more detail with reference to the following examples and comparative examples, but the scope of the present invention is not limited by the following examples.

Example  One

1. Preparation of first adhesive layer solution

A solution of CaO (average particle size of less than 5 탆) (20% of solid content) was prepared as a moisture adsorbent, and the solution was dispersed to make CaO uniformly distributed. Separately, a solution (solid content: 70%) obtained by diluting 100 g of an epoxy resin (YD-128, Kuko Chemical) and 70 g of phenoxy resin (YP-70, coagulable) with methyl ethyl ketone was prepared and the solution was homogenized . To the homogenized solution was added 250 g of a CaO solution prepared in advance, 5 g of imidazole (Shikoku Chemical) as a curing agent was added, and the mixture was stirred at a high speed for 1 hour to prepare a solution of the first adhesive layer.

2. Manufacturing of second adhesive layer solution

100 g of an epoxy resin (YD-128, Kukdo Chemical) and 90 g of a phenoxy resin (YP-70, coagulable) were diluted with methyl ethyl ketone to prepare a solution (solid content 70%), and the solution was homogenized. 5 g of imidazole (Shikoku Chemical) as a curing agent was added, and the mixture was stirred at high speed for 1 hour to prepare a solution of the second adhesive layer.

3. Preparation of adhesive film

The solution of the first adhesive layer prepared above was applied to the release surface of the releasing PET using a comma coater and dried at 130 캜 for 3 minutes in a dryer to form a first adhesive layer having a thickness of 50 탆.

The solution of the second adhesive layer prepared above was applied to the releasing surface of the releasing PET using a comma coater and dried at 130 DEG C for 3 minutes in a drier to form a second adhesive layer having a thickness of 5 mu m.

The first adhesive layer and the second adhesive layer were laminated to produce a multi-layered adhesive film (thickness ratio T1 / T2 = 10).

Example  2

An adhesive film was produced in the same manner as in Example 1 except that the thickness of the first adhesive layer was changed to 40 占 퐉 and the thickness of the second adhesive layer was changed to 10 占 퐉 (thickness ratio T1 / T2 = 4).

Example  3

An adhesive film was produced in the same manner as in Example 1 except that the thickness of the first adhesive layer was changed to 30 占 퐉 and the thickness of the second adhesive layer was changed to 15 占 퐉 (thickness ratio T1 / T2 = 2).

Example  4

An adhesive film was produced in the same manner as in Example 1 except that the thickness of the first adhesive layer was changed to 15 탆 and the thickness of the second adhesive layer was changed to 15 탆 (thickness ratio T1 / T2 = 1).

Comparative Example  One

An adhesive film was produced in the same manner as in Example 1 except that the thickness of the first adhesive layer was changed to 5 탆 and the thickness of the second adhesive layer was changed to 50 탆 (thickness ratio T1 / T2 = 0.1).

Comparative Example  2

An adhesive film was produced in the same manner as in Example 1 except that the thickness of the first adhesive layer was changed to 60 탆 and the thickness of the second adhesive layer was changed to 3 탆 (thickness ratio T1 / T2 = 20).

Comparative Example  3

An adhesive film was produced in the same manner as in Example 1 except that the thickness of the first adhesive layer was changed to 20 m and the thickness of the second adhesive layer was changed to 2 m (thickness ratio T1 / T2 = 10).

Comparative Example  4

An adhesive film was produced in the same manner as in Example 5 except that the thickness of the first adhesive layer was changed to 100 m and the thickness of the second adhesive layer was changed to 20 m (thickness ratio T1 / T2 = 5).

Comparative Example  5

An adhesive film having a thickness of 45 탆 and composed of only the first adhesive layer of Example 1 was produced by the same process as that of Example 1.

Comparative Example  6

An adhesive film having a thickness of 45 탆 and composed of only the second adhesive layer of Example 1 was produced by the same adhesive film production process as in Example 1.

Comparative Example  7

An adhesive film was produced in the same manner as in Example 1 except that the phenoxy resin of the second adhesive layer solution of Example 1 was changed to 20 g.

Experimental Example  1: Confirmation of moisture barrier property

In order to investigate the moisture barrier properties of the adhesive films of Examples 1 to 4 and Comparative Examples 1 to 7, a calcium test was conducted. Concretely, calcium (Ca) was deposited on a lower plate glass having a size of 100 mm × 100 mm by depositing 9 spots in a size of 5 mm × 5 mm and a thickness of 100 nm, and in addition, in Examples 1 to 4 and Comparative Examples 1 to 4, 7 was heat-bonded to a top plate glass having a size of 17 mm x 17 mm at 80 DEG C for 1 minute as shown in Fig. Thereafter, the adhesive film bonded to the upper plate glass was heat-bonded to the lower plate glass in the same vacuum (less than 100 mTorr). Thereafter, the cohered upper and lower plate glasses were cured in a high temperature drier at 100 ° C for 3 hours, and then the obtained specimens were allowed to stand in an environment of 85 ° C and 85% RH for 1000 hours in a constant temperature and humidity chamber, Was evaluated as the point at which the calcium began to become transparent due to the oxidation reaction due to penetration of moisture, and is shown in Table 1 below.

High temperature and high humidity 6mm 1000 hours - Passed calcium test Example 1 Calcium Good Example 2 Calcium Good Example 3 Calcium Good Example 4 Calcium Good Comparative Example 1 Less than 200 hours Comparative Example 2 Calcium Good Comparative Example 3 Calcium Good Comparative Example 4 Calcium Good Comparative Example 5 Calcium Good Comparative Example 6 Less than 100 hours Comparative Example 7 Calcium Good

Experimental Example  2: Check if organic electronic devices are damaged

An organic luminescent panel of 3 inches was prepared using the adhesive films of Examples 1 to 4 and Comparative Examples 1 to 7 and allowed to stand in an environment of 85 ° C and 85% RH for 1000 hours in a constant temperature and humidity chamber, The damage of the organic device was observed and is shown in Table 2 below. (However, damage caused by moisture penetration is a result of neglected condition.)

Damaged Example 1 Good Example 2 Good Example 3 Good Example 4 Good Comparative Example 1 Good Comparative Example 2 damaged Comparative Example 3 damaged Comparative Example 4 Good Comparative Example 5 damaged Comparative Example 6 Good Comparative Example 7 Good

In addition, a 3-inch organic luminescent panel manufactured using the adhesive film of Comparative Example 3 was allowed to stand at 85 ° C and 85% RH for 1000 hours in a thermo-hygrostat chamber, and an optical microscope image thereof is shown in FIG. Referring to FIG. 8, the thickness of the lower second adhesive layer is too thin to produce a hygroscopic filler contained in the first adhesive layer of the element, or a physical damage caused by the pressing of the particles, It is possible to confirm that dark spots were created by chemical damage caused by the material.

FIG. 9 shows an optical microscope photograph taken when the laminating process is simulated using the adhesive film prepared in Comparative Example 4. FIG. Referring to FIG. 9, it can be seen that the thickness of the entire adhesive layer is out of a certain range, thereby causing a problem in the adhesion of the panel in the manufacture of the panel. That is, it can be confirmed that the adhesiveness is exerted at the time of cementation and affects the fairness.

Experimental Example  3: Measurement of the interlayer viscosity difference

The viscosity of each of the first adhesive layer and the second adhesive layer of the adhesive films of Example 1 and Comparative Example 7 was measured using ARES, and the viscosity at 80 캜 and the difference therebetween are shown in Table 3 below.

The viscosity (Pa · s, 80 ° C) of the first adhesive layer The viscosity of the second adhesive layer (Pa 占 퐏, 80 占 폚) Interlayer viscosity difference
(Pa · s, 80 ° C) Example 1 2324 2349 25 Comparative Example 7 2324 2054 270

As can be seen from the above, the adhesive films of Examples 1 to 4 according to the embodiments of the present invention can effectively encapsulate the organic electronic device from moisture, but if the absolute thickness is too thin without satisfying the thickness ratio If the overall thickness is too thick, it can be seen that effective sealing of the organic electronic device is not achieved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be appreciated that other embodiments are possible. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

1, 2, 3, 4, 5: Adhesive film
11, 12, 21, 31, 32: adhesive layer
41, 51: substrate or release film
T1: thickness of the first adhesive layer
T2: thickness of the second adhesive layer
6: Organic electronic devices
61, 62: substrate
63: Organic electronic device

Claims (27)

An adhesive film for sealing a front surface of an organic electronic device,
Wherein the adhesive film comprises a first adhesive layer including a hygroscopic filler and a second adhesive layer not including a hygroscopic filler,
Wherein the ratio (T1 / T2) of the thickness (T1) of the first adhesive layer to the thickness (T2) of the second adhesive layer is 1.0 to 10. The adhesive film according to claim 1, wherein the thickness (T1) of the first adhesive layer is 5 占 퐉 or more and 100 占 퐉 or less. The adhesive film according to claim 1, wherein the thickness (T2) of the second adhesive layer is not less than 3 mu m and not more than 20 mu m. The adhesive film according to claim 1, wherein the adhesive film further comprises at least one or more adhesive layers that do not include a hygroscopic filler or at least one adhesive layer that includes a hygroscopic filler,
(T3 / T4) of the total thickness (T4) of the adhesive layers including the hygroscopic filler to the total thickness (T3) of the adhesive layers not including the hygroscopic filler is 1 to 10. The adhesive film according to claim 4, wherein an adhesive layer not including a hygroscopic filler is disposed on the lowermost portion of the multilayer adhesive layer. 5. The adhesive film according to claim 4, wherein adhesive layers not containing the hygroscopic filler are disposed at the lowermost and uppermost portions of the multilayered adhesive layer. The adhesive film according to claim 1, wherein the adhesive layer has a viscosity at room temperature of 10 ⁶ Pa · s or more. The adhesive film according to claim 1, wherein the viscosity difference between the first adhesive layer and the second adhesive layer in an uncured state in a temperature range of 30 ° C to 130 ° C is 100 Pa · s or less. The adhesive film according to claim 1, wherein the total thickness of the adhesive layer is 100 m or less. The adhesive film according to claim 1, wherein the adhesive layer comprises a curable resin, and the curable resin is a thermosetting resin, a photo-curing resin or a dual curing resin. The curable resin composition according to claim 10, wherein the curable resin comprises at least one curable functional group selected from a glycidyl group, a hydroxyl group, an isocyanate group, a carboxyl group, an amide group, an epoxide group, a cyclic ether group, a sulfide group, an acetal group and a lactone group Lt; / RTI > The adhesive film according to claim 1, wherein the hygroscopic filler is alumina, a metal oxide, a metal salt, or phosphorus pentoxide as the water-reactive adsorbent. The method of claim 1 wherein the hygroscopic filler is _{P 2 O 5, Li 2 O} , Na 2 O, BaO, CaO, MgO, Li 2 SO 4, Na 2 SO 4, CaSO 4, MgSO 4, CoSO 4, Ga 2 _{(SO 4) 3, Ti (} SO 4) 2, NiSO 4, CaCl 2, MgCl 2, SrCl 2, YCl 3, CuCl 2, CsF, TaF 5, NbF 5, LiBr, CaBr 2, CeBr 3, SeBr 4, Wherein the adhesive film is at least one selected from the group consisting of VBr ₃ , MgBr ₂ , BaI ₂ , MgI ₂ , Ba (ClO ₄ ) ₂ and Mg (ClO ₄ ) ₂ . The adhesive film according to claim 1, wherein the first adhesive layer comprises a hygroscopic filler in an amount of 5 to 50 parts by weight based on 100 parts by weight of the curable resin. The adhesive film of claim 1, wherein the adhesive layer further comprises a filler. The adhesive film according to claim 15, wherein the filler is at least one selected from the group consisting of clay, talc, silica, barium sulfate, aluminum hydroxide, calcium carbonate, magnesium carbonate, zeolite, zirconia, titania or montmorillonite. The adhesive film according to claim 15, wherein the adhesive layer comprises 3 to 50 parts by weight of a filler per 100 parts by weight of the curable resin. The adhesive film according to claim 1, wherein the adhesive layer further comprises a curing agent. The adhesive film according to claim 18, wherein the curing agent is an amine compound, an imidazole compound, a phenol compound, a phosphorus compound or an acid anhydride compound. The adhesive film according to claim 18, wherein the adhesive layer comprises 1 to 10 parts by weight of a curing agent based on 100 parts by weight of the curable resin. The adhesive film according to claim 1, wherein the adhesive layer further comprises a binder resin. Board; An organic electronic device formed on the substrate; And an adhesive film according to any one of claims 1 to 21 for sealing the organic electronic device, wherein a second adhesive layer not containing the hygroscopic filler of the adhesive film is adhered to the front surface of the organic electronic device Organic electronic device. 23. The organic electronic device according to claim 22, wherein the organic electronic device is an organic light emitting diode. Applying an adhesive film according to any one of claims 1 to 21 to a substrate comprising an organic electronic device formed on the top so that a second adhesive layer of the adhesive film adheres to the front surface of the organic electronic device; And curing the adhesive film. The method of encapsulating organic electronic devices according to claim 24, wherein the step of applying the adhesive film to the organic electronic device is performed by a hot roll laminate, a hot press, or a vacuum press method of an adhesive film. The method of encapsulating an organic electronic device according to claim 24, wherein the step of applying the adhesive film to the organic electronic device is performed at a temperature of 50 캜 to 100 캜. The method of encapsulating organic electronic device according to claim 24, wherein the curing step is carried out by heating to a temperature range of 70 占 폚 to 110 占 폚 or by irradiating with UV light.

Images