WO2014021687A1 - Adhesive film and method for encapsulating organic electronic device using same - Google Patents

Abstract

The present invention relates to an adhesive film, to an encapsulated product of an organic electronic device using same and to a method for encapsulating an organic electronic device using same. More particularly, an adhesive film for encapsulating an organic electronic device comprises: a protective film layer, a first adhesive layer, a second adhesive layer and a release film layer sequentially arranged. The peel strength (A) between the first adhesive layer and the protective film layer is lower than the peel strength (B) between the second adhesive layer and the release film layer, and the peel strength (B) between the second adhesive layer and the release film layer is lower than the peel strength (C) between the first adhesive layer and an encapsulation substrate, thus improving faults during a peeling process.

Description

Adhesive film and sealing method of organic electronic device using same

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

An organic electronic device (OED) refers to a device including an organic material layer that generates an exchange of electric charges using holes and electrons, and examples thereof include a photovoltaic device, a rectifier, Transmitters and organic light emitting diodes (OLEDs); and the like.

Among the organic electronic devices, organic light emitting diodes (OLEDs) have low power consumption, fast response speed, and are advantageous for thinning a display device or lighting, as compared with conventional light sources. In addition, OLED has excellent space utilization, and is expected to be applied in various fields including various portable devices, monitors, notebooks, and TVs.

In the commercialization of OLEDs and the expansion of their use, the main problem is durability. Organic materials and metal electrodes included in the OLED are very easily oxidized by external factors such as moisture. Therefore, products containing OLEDs are highly sensitive to environmental factors. Accordingly, various methods have been proposed to effectively block the penetration of oxygen or moisture from the outside into organic electronic devices such as OLEDs, and one of them is a method of using an adhesive film.

However, the conventional OLED encapsulation adhesive film is composed of a single layer between two release films, and has a problem in that the adhesion peeling property is very low. In particular, as the size of the adhesive film increases due to the large area of the OLED, the peeling failure rate of the adhesive film during the encapsulation process of the OLED increases. For example, peeling defects in which the lifting phenomenon of the adhesive film occurs during peeling of the protective film or the release film protecting the adhesive film are generated.

In order to solve this problem, an attempt was made to simply use a release film having different peeling properties, but that alone could not solve the defect.

Accordingly, there is a need for development of an adhesive film for encapsulation that can effectively block moisture penetration while reducing damage to organic electronic devices and at the same time improve process defects that can occur in an OLED encapsulation process.

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

The present invention is a protective film; A first adhesive layer formed on the protective film; A second adhesive layer formed on the first adhesive layer; And a release film formed on the second adhesive layer, wherein the first adhesive layer and the second adhesive layer provide an adhesive film for sealing an organic electronic device satisfying the following general formula (1).

[Formula 1]

C> B> A

Where A represents the peel force between the first adhesive layer and the protective film, B represents the peel force between the second adhesive layer and the release film, and C is the peel force between the first adhesive layer and the encapsulation substrate after the protective film is removed. Indicates.

In addition, the present invention is a substrate; An organic electronic device formed on the substrate; And the adhesive film encapsulating the organic electronic device, wherein the adhesive film includes a first adhesive layer and a second adhesive layer.

When encapsulating the organic electronic device using the adhesive film according to the embodiments of the present invention, by improving the defect that the adhesive film is lifted or accompanied when peeling off the protective film and / or release film used to protect the adhesive film Process defects can be prevented.

1 is a cross-sectional view showing an adhesive film according to one example of the present invention.

2 to 4 are cross-sectional views illustrating some processes of applying an adhesive film according to an example of the present invention to an organic electronic device encapsulation process.

[Description of the code]

1: protective film layer

2: curable adhesive layer

2a: first adhesive layer

2b: second adhesive layer

3: release film layer

4: encapsulation substrate

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in describing the present invention, detailed descriptions of related well-known general functions or configurations are omitted. In addition, the accompanying drawings are schematic for the purpose of better understanding of the present invention, and in order to more clearly describe the present invention, parts irrelevant to the description are omitted, and in order to clearly express various layers and regions in the drawings, the thickness is enlarged. It is shown, and the scope of the present invention is not limited by the thickness, size, ratio and the like shown in the drawings.

The adhesive film according to an embodiment of the present invention encapsulates the organic electronic device, and includes an adhesive layer having a multilayer structure.

Adhesive film according to an embodiment of the present invention is a protective film; A first adhesive layer formed on the protective film; A second adhesive layer formed on the first adhesive layer; And a release film formed on the second adhesive layer, wherein the first adhesive layer and the second adhesive layer satisfy the following general formula (1).

[Formula 1]

C> B> A

Where A represents the peel force between the first adhesive layer and the protective film, B represents the peel force between the second adhesive layer and the release film, and C is the peel force between the first adhesive layer and the encapsulation substrate after the protective film is removed. Indicates.

In one example, the first adhesive layer and the second adhesive layer may satisfy the following general formula (2).

[Formula 2]

B-A ≥ 5 gf / 25mm

In addition, the first adhesive layer and the second adhesive layer may satisfy the following general formula (3).

[Formula 3]

C-B ≥ 16 gf / 25mm

As used herein, the term "organic electronic device" means an article or device having a structure including an organic material layer that generates an exchange of electric charge using holes and electrons between a pair of electrodes facing each other. The photovoltaic device, a rectifier, a transmitter, and an organic light emitting diode (OLED) may be mentioned, but is not limited thereto. In one example of the present invention, the organic electronic device may be an OLED.

In the present specification, the encapsulation substrate may be a glass or a polymer film, but is not limited thereto. Any encapsulation substrate may be used without limitation as long as it can encapsulate an adhesive film.

The adhesive film according to embodiments of the present invention may have various structures as long as the structure satisfies the above structure. For example, as shown in FIG. 1, the protective film layer 1 and the curable adhesive layer 2 are sequentially formed from the bottom. ) And a release film layer 3 on the curable adhesive layer 2, wherein the curable adhesive layer 2 has a two-layer structure, and includes a first adhesive layer 2a and a second adhesive layer 2b. The release film layer 3 is formed on the second adhesive layer 2b. The method for allowing the adhesive layer 2 to have a multi-layer structure may be any method used in the art without limitation, provided that the adhesive layer 2 has a multi-layer structure.

The protective film layer (1) is formed to protect the curable adhesive layer (2) in the storage and transport step after the manufacture of the adhesive film, the release film layer (3) as a substrate in the manufacture of the curable adhesive layer (2) A film that is used and subsequently peeled off after being applied to an adherend. That is, when the adhesive film according to the embodiments of the present invention is ultimately applied to the encapsulation of the organic electronic device, the protective film layer 1 and the release film layer 3 are not included in the organic electronic device encapsulation product.

As such, when the adhesive film is applied to the encapsulation process of the organic electronic device, a peeling process of the protective film layer 1 and a peeling process of the release film layer 3 are required, wherein the protective film layer 1 and the release film layer ( 3) It is necessary to reduce the defect that peels cleanly and the adhesive film is lifted up or partly peeled off.

2 to 4 are cross-sectional views illustrating some processes of applying an adhesive film according to an example of the present invention to an organic electronic device encapsulation process. 2 to 4 are processes that take place in order. First, as shown in FIG. 2, the protective film layer 1 is peeled from the adhesive film at room temperature in order to use the adhesive film of the present invention for sealing an organic electronic device. Subsequently, as the protective film layer 1 is peeled off, the first adhesive layer 2a in contact with the outside is attached to the encapsulation substrate 4, and the encapsulation substrate (for example, a hot-roll lamination process) is attached to the encapsulation substrate 4. 4) and increase the adhesive strength of the adhesive film. Then, at room temperature, the release film layer 3 on the opposite side of the adhesive film to which the encapsulation substrate is finally attached is peeled off, and the adhesive film is used for the sealing process of the organic electronic device.

The adhesive film according to the embodiments of the present invention used in such a process, in order to improve the peeling defect phenomenon, the peel force between the first adhesive layer (2a) and the protective film layer (1) as shown in the general formula 1 (A) is lower than the peeling force B between the 2nd contact bonding layer 2b and the release film layer 3. Therefore, as shown in FIG. 2, it is possible to prevent the adhesive layer 2 from lifting at the interface with the release film layer 3 during the peeling process of the protective film layer from which the protective film layer 1 is removed.

In addition, in the adhesive film according to the embodiments of the present invention, the peeling force B between the second adhesive layer 2b and the release film layer 3 has a peeling force between the first adhesive layer 2a and the encapsulation substrate 4. Lower than (C). Therefore, after attaching the first adhesive layer 2a exposed to the outside after peeling off of the protective film layer 1 to the encapsulation substrate 4 as shown in FIG. 3, the adhesive film is adhered to the encapsulation substrate by a thermal bonding process. In the process of removing the release film layer 3 as illustrated in FIG. 4, the adhesive layer 2 may be prevented from being lifted or torn off from the encapsulation substrate 4 when the release film layer 3 is peeled off.

That is, the adhesive film according to embodiments of the present invention can improve the peeling failure by varying the two-side peeling force of the two or more adhesive layers. In one example, the difference BA of each release peel force between the first adhesive layer 2a and the second adhesive layer 2b is 5 gf / 25mm or more and 5 gf / 25mm or more, as shown in the general formula (2). 30 gf / 25mm, preferably 6 gf / 25mm to 28 gf / 25mm, more preferably 8 gf / 25mm to 25 gf / 25mm, more preferably 10 gf / 25mm to 20 gf / 25mm, or most preferably 12 gf / 25mm to 18 gf / 25mm. In another example, the difference CB between the first adhesive layer 2a and the encapsulation substrate 4 and the peel force between the second adhesive layer 2b and the release film layer 3 is 16 gf / 25mm. The above may be 16 gf / 25mm to 60 gf / 25mm, 17 gf / 25mm to 50gf / 25mm, 18 gf / 25mm to 45 gf / 25mm, or 20 gf / 25mm to 40 gf / 25mm. The peel force may be measured using a texture analyzer and measured using ASTM3330.

As described above, setting the peel force of the adhesive film to be higher in the order of A, B, and C may be performed, for example, as follows.

First, controlling the peeling force A between the first adhesive layer 2a and the protective film layer 1 to be lower than the peeling force B between the second adhesive layer 2b and the release film layer 3 controls the composition of each layer. It may be set differently or by imparting a surface additive to each adhesive layer. For example, to adjust the composition of the two adhesive layers differently, for example, the flow of liquid epoxy having a flow at room temperature to adjust the content contained in the adhesive layer, wherein the content of the liquid epoxy is based on the total of each adhesive layer 5 To 70% by weight.

In addition, there may be a method of adding a surface additive to either one of the first adhesive layer 2a and the second adhesive layer 2b, and there may be a method of varying the content while adding the surface additive to each of the adhesive layers. have. Alternatively, other types of surface additives suitable for the surface properties inherent to the release film or the protective film may be selectively used in each layer. Through the addition of such surface additives and the difference in content, the wettability of the protective film or the release film and the sealing substrate of each adhesive layer may be improved. As the surface additives as described above, vinyl-based, amino-based, epoxy-based, methacloroxine silane coupling agents, polyester-modified acrylics, polyurethanes, acrylic copolymers and the like can be used.

By adjusting the surface additives or changing the composition included in each adhesive layer as described above, the peeling force B between the second adhesive layer 2b and the release film layer 3 is applied to the first adhesive layer 2a and the protective film layer ( 1) can be adjusted more than 5 gf / 25mm higher than the peel force (A) between.

In addition, adjusting the peeling force B between the second adhesive layer 2b and the release film layer 3 to be lower than the peeling force C between the first adhesive layer 2a and the encapsulation substrate 4 is, for example. It can be made as follows. Specifically, the release peeling force (B) between the second adhesive layer (2b) and the release film layer (3) is a room temperature between the first adhesive layer (2a) and the sealing substrate 4 after the thermal bonding step as shown in FIG. It is lower than the peel force (C), the adhesive film is attached to the encapsulation substrate 4 by a thermal bonding process such as hot-roll lamination, the flow of the adhesive layer is generated by heat, Adhesion and adhesion are maximized. For example, the content of the polymer resin having a softening point of 40 ° C. or higher in the first adhesive layer 2a may be 10 to 70 wt%, 20 to 60 wt%, 25 to 50 wt%, or 30 based on the entire layer. To 40% by weight.

In this case, the thermal bonding process of increasing the peel force C between the first adhesive layer 2a and the encapsulation substrate 4 may be performed at a temperature of 40 to 80 ° C. The adhesive force C between the first adhesive layer 2a and the encapsulation substrate 4 after such a thermal bonding process is 16 gf / compared with the peeling force B between the second adhesive layer 2b and the release film layer 3. It can be adjusted higher than 25mm.

The adhesive film may have a viscosity at room temperature of 10 ⁶ dyne / cm ² or more, preferably 10 ⁷ dyne / cm ^{2 or} more. The term "room temperature" means a natural temperature that is not warmed or reduced, for example, about 15 ° C to 35 ° C, more specifically about 20 ° C to 25 ° C, and more specifically about 25 ° C. Can mean. The said viscosity can be measured using ARES (Advanced Rheometric Expansion System). In the present invention, by adjusting the viscosity of the adhesive layer in the above range, in the encapsulation process of the organic electronic device, the processability of the operation is smooth and the flat plate can be sealed with a uniform thickness. In addition, it is possible to greatly reduce problems such as shrinkage and volatile gas, which may occur due to curing of the resin, to prevent physical or chemical damage to the organic electronic device. In the present invention, as long as the adhesive layer maintains a solid or semi-solid state at room temperature, the upper limit of the viscosity is not particularly limited. For example, in consideration of processability, the upper limit of the viscosity is in the range of about 10 ⁹ dyne / cm ² or less. Can be controlled.

The curable resin included in the curable adhesive layer has a water vapor transmission rate (WVTR) in a cured state of 50 g / m ² · day or less, 30 g / m ² · day or less, 20 g / m ² · day or less Or 15 g / m ² · day or less. The term “cured state of the curable resin” refers to a curable resin that is cured or crosslinked through its reaction with other components such as alone or with a curing agent or the like, and when used as an encapsulant, retains components such as moisture adsorbents and fillers, It means the state converted to the state which can exhibit the performance as a structural adhesive. In this invention, the said water vapor transmission rate is the water vapor transmission rate measured with respect to the thickness direction of the said hardened | cured material under 38 degreeC and 100% of relative humidity, after hardening curable resin and making the hardened | cured material into the film form of thickness 80micrometer. In addition, the moisture permeability is measured according to ASTM F1249.

By controlling the moisture permeability within the above range, the penetration of moisture, moisture or oxygen into the organic electronic device encapsulation product can be effectively suppressed, and the introduction effect of the moisture reactive adsorbent can be exerted.

In the present invention, the moisture permeability in the cured state of the resin is such that the lower the numerical value, the better the sealing structure is. The lower limit is not particularly limited.

The specific kind of curable resin that can be used in the present invention is not particularly limited, and various thermosetting or photocurable resins known in the art may be used. The term "thermosetting resin" means a resin that can be cured through an appropriate heat application or aging process, and the term "photocurable resin" means a resin that can be cured by irradiation of electromagnetic waves. In addition, in the above category of electromagnetic waves, microwaves, infrared (IR), ultraviolet (UV), X-rays and γ-rays, as well as α-particle beam (proton beam), proton beam (neutron) Particle beams such as neutron beams and electron beams may be included. One example of the photocurable resin in the present invention includes a cationic photocurable resin. The cationic photocurable resin means a resin that can be cured by cationic polymerization or cation curing reaction induced by irradiation of electromagnetic waves. In addition, the curable resin may be a dual curable resin including both thermosetting and photocuring properties.

The specific kind of curable resin in this invention will not be restrict | limited especially if it has the above-mentioned characteristic. For example, it may be cured to exhibit adhesive properties, and may include one or more thermosetting functional groups such as glycidyl group, isocyanate group, hydroxy group, carboxyl group or amide group, or may be an epoxide group or a cyclic ether. and resins containing at least one functional group curable by irradiation of electromagnetic waves such as a (cyclic ether) group, a sulfide group, an acetal group, or a lactone group. In addition, specific types of the resin may include an acrylic resin, a polyester resin, an isocyanate resin, an epoxy resin, and the like, but is not limited thereto.

In the present invention, the curable resin, aromatic or aliphatic; Or an epoxy resin of linear or branched chain type can be used. In one embodiment of the present invention, as containing two or more functional groups, an epoxy resin having an epoxy equivalent of 180 g / eq to 1,000 g / eq may 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 epoxy resins include cresol novolac epoxy resins, bisphenol A epoxy resins, bisphenol A novolac epoxy resins, phenol novolac epoxy resins, tetrafunctional epoxy resins, biphenyl epoxy resins, and triphenol methane types. A kind or mixture of an epoxy resin, an alkyl modified triphenol methane epoxy resin, a naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin, or a dicyclopentadiene modified phenol type epoxy resin is mentioned.

In the present invention, an epoxy resin preferably containing a cyclic structure in the molecular structure can be used, and more preferably an epoxy resin containing an aromatic group (for example, a phenyl group) can be used. When the epoxy resin contains an aromatic group, the cured product may have excellent thermal and chemical stability while exhibiting low moisture absorption, thereby improving reliability of the organic electronic device encapsulation structure. Specific examples of the aromatic group-containing epoxy resin that can be used in the present invention include biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene modified phenol type epoxy resin, cresol type epoxy resin, Bisphenol-based epoxy resins, xylox-based epoxy resins, polyfunctional epoxy resins, phenol novolac epoxy resins, triphenol methane-type epoxy resins and alkyl-modified triphenol methane epoxy resins, such as one or a mixture of two or more, but is not limited thereto. no.

More preferably in the present invention, as the epoxy resin, a silane-modified epoxy resin, preferably a silane-modified epoxy resin having an aromatic group can be used. As such, when an epoxy resin modified with silane and structurally having a silane group is used, the adhesion of the organic electronic device to the glass substrate or the substrate inorganic material can be maximized, and the moisture barrier property, durability and reliability can be improved. The specific kind of the above epoxy resin that can be used in the present invention is not particularly limited, and such a resin can be easily obtained from a place of purchase such as, for example, National Chemical.

The adhesive film may further comprise a moisture adsorbent and / or a filler. The moisture adsorbent and / or filler may be included in the first adhesive layer or the second adhesive layer, may be included in all, and the content may be the same or different.

The term "moisture adsorbent" may be used as a generic term for a moisture reactive adsorbent that is a component capable of adsorbing or removing moisture or moisture introduced from the outside through a chemical reaction or the like.

The moisture adsorbent chemically reacts with moisture, moisture, or oxygen introduced into the adhesive layer to adsorb moisture or moisture.

The specific kind of water adsorbent that can be used in the present invention is not particularly limited. For example, in the case of a water reactive adsorbent, metal powder such as alumina, metal oxide, metal salt or phosphorus pentoxide (P ₂ O ₅ ), or the like And mixtures of two or more kinds. Examples of the physical adsorbent include silica, zeolite, titania, zirconia, montmorillonite, and the like.

Specific examples of the metal oxides include lithium oxide (Li ₂ O), sodium oxide (Na ₂ O), barium oxide (BaO), calcium oxide (CaO), magnesium oxide (MgO), and the like. 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 ), gallium sulfate (Ga ₂ (SO ₄ ) ₃ ), sulfates such as titanium sulfate (Ti (SO ₄ ) ₂ ) or nickel sulfate (NiSO ₄ ), calcium chloride (CaCl ₂ ), magnesium chloride (MgCl ₂ ), strontium chloride (SrCl ₂ ), yttrium chloride (YCl ₃ ) Copper 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 ), selenium bromide Metal halides such as (SeBr ₄ ), vanadium bromide (VBr ₃ ), 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, but is not limited thereto.

In the present invention, a water adsorbent such as the metal oxide can be blended into the composition in a state of being properly processed. For example, the thickness of the adhesive layer may be a thin film of 30 μm or less according to the type of organic electronic device to which the adhesive film is to be applied, and in this case, a grinding process of the moisture absorbent may be required. For grinding of the moisture adsorbent, a process such as a three roll mill, bead mill or ball mill may be used. In addition, when the adhesive film of the present invention is used for organic light emitting devices of the top emission type or the like, the permeability of the adhesive layer itself becomes very important, and thus the size of the moisture adsorbent needs to be small. Therefore, the grinding process may be required even in such applications.

The filler may inhibit the penetration by lengthening the movement path of moisture or moisture that penetrates into the encapsulation structure, and maximize the barrier to moisture and moisture through interaction with the matrix structure of the curable resin and the moisture absorbent. have. The specific kind of filler that can be used in the present invention is not particularly limited, and for example, a mixture of one or more kinds selected from the group consisting of clay, talc, silica, zeolite, zirconia, titania and montmorillonite may be used.

In the present invention, in order to increase the coupling efficiency between the filler and the organic binder, a product surface-treated with an organic material may be used as the filler, or a coupling agent may be additionally added.

The curable adhesive layer of the present invention may include 1 part by weight to 50 parts by weight, and preferably 1 part by weight to 20 parts by weight of filler, based on 100 parts by weight of the curable resin. By controlling the filler content to 1 part by weight or more, it is possible to provide a cured product having excellent moisture or moisture barrier properties and mechanical properties. In addition, by controlling the filler content to 50 parts by weight or less in the present invention, it is possible to manufacture a film form, it is possible to provide a cured product exhibiting excellent moisture barrier properties even when formed into a thin film.

The curable adhesive layer of the present invention may further include a curing agent capable of reacting with the curable resin to form a matrix such as a crosslinked structure.

The specific kind of hardening | curing agent which can be used by this invention is not specifically limited, It can select suitably according to the kind of curable resin used or the functional group contained in the resin. For example, when using an epoxy resin as curable resin in this invention, the hardening | curing agent for general epoxy resins known in this field can be used as a hardening | curing agent, Specifically, various amine compounds, imidazole compound, phenol type One kind or two or more kinds of compounds, phosphorus compounds or acid anhydride compounds may be used, but is not limited thereto.

The curable adhesive layer of the first and second regions of the present invention contains a curing agent in an amount of 1 part by weight to 20 parts by weight, preferably 1 part by weight to 10 parts by weight, for example, based on 100 parts by weight of the thermosetting resin. can do. However, the content is only one example of the present invention. That is, in the present invention, the content of the curing agent may be changed according to the type and content of the curable resin or functional group, or the matrix structure or crosslinking density to be implemented.

The curable adhesive layer of the present invention may further contain a polymer resin. The polymer resin may serve to improve moldability, for example, when molding the composition of the present invention into a film or sheet shape. In addition, it may serve as a high temperature viscosity modifier to control the flow during the heat bonding process. The polymer resin may have a softening point of 40 ° C. or higher, and the polymer resin may have a content of 10 to 70 wt%, 20 to 60 wt%, 25 to 50 wt%, or 30 to 40 wt% based on the entire layer. You can adjust it.

The type of polymer resin that can be used in the present invention is not particularly limited as long as it has compatibility with other components such as the curable resin. Specific examples of the polymer resin that can be used are resins having a weight average molecular weight of 20,000 or more, such as phenoxy resins, acrylate resins, high molecular weight epoxy resins, rubbers containing high polarity functional groups and high polarity functional groups containing reactivity. One kind or a mixture of two or more kinds of rubber, etc. may be mentioned, but is not limited thereto.

When the polymer resin is included in the curable adhesive layer of the present invention, the content is not particularly limited to be adjusted according to the desired physical properties. For example, in the present invention, the polymer resin may be included in an amount of about 200 parts by weight or less, preferably 150 parts by weight or less, and more preferably about 100 parts by weight or less based on 100 parts by weight of the curable resin. In the present invention, by controlling the content of the polymer resin to 200 parts by weight or less, it can effectively maintain the compatibility with each component of the resin composition, it can also serve as an adhesive.

The adhesive film of the present invention, in addition to the addition of additives such as an additional filler for improving the durability of the cured product, a mechanical strength, a coupling agent for improving the adhesive strength, a plasticizer, a UV stabilizer, and an antioxidant, within a range that does not affect the effect of the invention. It may include.

The specific kind of the said protective film layer or a release film layer which can be used by this invention is not specifically limited. In the present invention, as the protective film layer or the release film layer, for example, a general polymer film in this field can be used. In the present invention, for example, as the protective film layer or the release film layer, polyethylene terephthalate film, polytetrafluoroethylene film, polyethylene film, polypropylene film, polybutene film, polybutadiene film, vinyl chloride copolymer film, Polyurethane films, ethylene-vinyl acetate films, ethylene-propylene copolymer films, ethylene-ethyl acrylate copolymer films, ethylene-methyl acrylate copolymer films, polyimide films and the like can be used. In addition, an appropriate release treatment may be performed on one side or both sides of the protective film layer or the release film layer of the present invention. Alkyd-based, silicone-based, fluorine-based, unsaturated ester-based, polyolefin-based, wax-based, or the like may be used as an example of the release agent used for the release treatment of the protective film layer or the release film layer, and among them, alkyd-based, silicone-based, or fluorine-based It is preferred to use a release agent, but is not limited thereto.

In the present invention, the thickness of the protective film layer or the release film layer as described above is not particularly limited, and may be appropriately selected depending on the intended use. For example, in the present invention, the thickness of the first film may be about 10 μm to 500 μm, or about 20 μm to 200 μm. If the thickness is less than 10 μm, deformation of the base film may occur easily during the manufacturing process. If the thickness is more than 500 μm, the economy is inferior.

The thickness of the adhesive layer included in the adhesive film of the present invention is not particularly limited and may be appropriately selected in consideration of the use to which the film is applied.

In this invention, the method of manufacturing such an adhesive film is not specifically limited. For example, a first step of coating a coating liquid containing the composition of the adhesive layer described above on a protective film layer or a release film layer; And a second step of drying the coating solution coated in the first step, thereby preparing each adhesive layer of the adhesive film.

Another embodiment of the invention is a substrate; An organic electronic device formed on the substrate; And a first adhesive layer and a second adhesive layer of the aforementioned adhesive film encapsulating the organic electronic device.

In the present invention, the organic electronic device may be an organic light emitting diode.

The organic electronic device encapsulation product may further include a protective film protecting the organic electronic device between the adhesive film and the organic electronic device.

Another embodiment of the present invention comprises the steps of peeling the protective film from the above-mentioned adhesive film; Attaching the first adhesive layer to the encapsulation substrate; Peeling off the release film; And laminating the second adhesive layer to be in contact with the organic electronic device.

 The step of attaching the first adhesive layer to the encapsulation substrate is a method of encapsulating an organic electronic device in which the Big C force between the first adhesive layer and the encapsulation substrate and the peel force B between the second adhesive layer and the release film satisfy the following general formula (3). To provide.

[Formula 3]

C-B ≥ 16 gf / 25mm

The applying of the adhesive film to the organic electronic device may be performed by hot roll lamination, hot pressing, or vacuum pressing of the adhesive film, and is not particularly limited.

Attaching the first adhesive layer to the encapsulation substrate may be a step of laminating the first adhesive layer to the encapsulation substrate at 40 ° C. to 100 ° C., 60 ° C. to 80 ° C., or 70 ° C. to 90 ° C. FIG.

The step of attaching the first adhesive layer to the encapsulation substrate may include a difference between the Big C force between the first adhesive layer and the encapsulation substrate, and the peel force B between the second adhesive layer and the release film, CB of 16 gf / 25 mm or more and 16 gf / 25 mm to 40 gf / 25mm, 16 gf / 25mm to 35gf / 25mm, 16 gf / 25mm to 20 gf / 25mm, or 17 gf / 25mm to 22 gf / 25mm.

The applying of the adhesive film to the organic electronic device may be performed at a temperature of 50 ° C. to 90 ° C., and the second adhesive layer may cover the entire surface of the organic electronic device.

It may further comprise the step of curing the adhesive layer and the curing step may be carried out by heating to a temperature range of 70 ℃ to 110 ℃ or UV irradiation.

In the method of encapsulating an organic electronic device in the present invention, for example, a transparent electrode is formed on a substrate such as glass or a polymer film by vacuum deposition or sputtering, and an organic material layer is formed on the transparent electrode. The organic material layer may include a hole injection layer, a hole transport layer, a light emitting layer, an electron injection layer and / or an electron transport layer. Subsequently, a second electrode is further formed on the organic material layer. Then, the above-described adhesive film is applied to cover all of the organic electronic devices on the organic electronic device on the substrate. At this time, the method of applying the adhesive film is not particularly limited, and, for example, an encapsulation substrate (ex. Glass or polymer) in which the adhesive layer of the adhesive film of the present invention is previously transferred onto the organic electronic device formed on the substrate. Film) can be applied by a method such as heating or pressing. In the above step, for example, when transferring the adhesive film on the sealing substrate, using the adhesive film of the present invention described above, after peeling off the protective film or the release film formed on the film, applying a heat, vacuum press Or transfer to an encapsulation substrate using a vacuum laminator or the like. In this process, when the curing reaction of the adhesive film is made in a certain range or more, the adhesive force or the adhesive force of the adhesive film may be reduced. Therefore, it is preferable to control the process temperature to about 100 ° C. or less and the process time within 5 minutes. Similarly, a vacuum press or a vacuum laminator may be used even when the encapsulation substrate onto which the adhesive film has been transferred is heat-compressed to the organic electronic device. The temperature conditions at this stage can be set as described above, and the process time is preferably within 10 minutes. However, the adhesive film is applied to the organic electronic device so that the adhesive layer of the first region is in contact with the organic electronic device rather than the second region of the adhesive film (in case the organic electronic device is provided with the protective film).

In addition, in the present invention, an additional curing process may be performed on the adhesive film obtained by compressing the organic electronic device. The curing process (main curing) may be performed in, for example, a heating chamber or a UV chamber. Conditions in the present curing may be appropriately selected in consideration of the stability of the organic electronic device.

However, the above-described manufacturing process is only one example for encapsulating the organic electronic device of the present invention, and the process sequence or process conditions may be freely modified. For example, in the present invention, the order of the transfer and the pressing process may be changed by first transferring the adhesive film of the present invention to the organic electronic device on the substrate and then compressing the encapsulation substrate. In addition, the protective layer may be formed on the organic electronic device, the adhesive film may be applied, and the encapsulation substrate may be omitted and cured.

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

Example 1.

1. Preparation of the first adhesive layer solution

CaO (Aldrich) was added to methyl ethyl ketone at a concentration of 30wt% as a water adsorbent to prepare a water adsorbent solution, and the solution was milled for 24 hours by a ball mill process. 60 parts by weight of BPA type liquid YD-128 (Kukdo Chemical) as an epoxy resin, 0.1 parts by weight of KBM-403 (Shin-Etsu) as a surface additive, and 40 parts of YP-70 (Kukdo Chemical) as a polymer resin having a softening point of 40 ° C or higher. Added wealth. Into the homogenized solution, 6 parts by weight of a curing agent 2PZ-CNS (shikoku) is added. 5 parts by weight of the milling solution was added to the resin, and methyl ethyl ketone was added so that the total solid content was 50%, followed by high speed stirring for 1 hour to prepare a solution of the first adhesive layer.

2. Preparation of the second adhesive layer solution

60 parts by weight of BPA type liquid YD-128 (Kukdo Chemical) as an epoxy resin, 0.1 parts by weight of KBM-403 (Shin-Etsu) as a surface additive, and YP-70 (Kukdo Chemical) as a polymer resin having a softening point of 40 ° C or higher. Part by weight was added. Into the homogenized solution, 6 parts by weight of 2PZ-CNS (Shikoku Chemical), which is a curing agent, is added. Methyl ethyl ketone was added so that the total solid content was 50%, followed by high speed mixing for 1 hour to prepare a solution of the second adhesive layer.

3. Preparation of Adhesive Film

The solution of the second adhesive layer prepared above was applied to the release surface of the release PET using a comma coater and dried at 130 ° C. for 3 minutes in a dryer to form an adhesive layer having a thickness of 15 μm.

The solution of the first adhesive layer prepared above was applied to the release surface of the release PET using a comma coater and dried at 130 ° C. for 3 minutes in a dryer to form an adhesive layer having a thickness of 30 μm.

The adhesive layer of the first adhesive layer and the second adhesive layer were laminated to prepare a multilayer adhesive film.

4. Encapsulation board attachment

After removing a protective film and measuring peeling force A, the sealing substrate is formed using a vacuum press or a vacuum laminator etc., applying heat.

Example 2

In the manufacturing process of the adhesive film of Example 1, by varying the weight ratio of the surface additives of the first adhesive layer and the second adhesive layer (increase by 0.2 parts by weight of the additive content for the surface of the first adhesive layer, the additive for the surface of the second adhesive layer An adhesive film having a multilayer structure was prepared in the same manner as in Example 1 except that the content was increased to 0.5 parts by weight.

Example 3

In the manufacturing process of the adhesive film of Example 1, by varying the weight ratio of the epoxy resin of the first adhesive layer and the second adhesive layer (controlling the content of the liquid epoxy and the polymer resin of the first adhesive layer at a ratio of 65:35, The adhesive film having a multilayer structure was prepared in the same manner as in Example 1 except that the content of the liquid epoxy and the polymer resin in the adhesive layer was adjusted at a ratio of 62:38.

Comparative Example 1

In the adhesive film manufacturing process of Example 1, a multilayer film adhesive film was prepared in the same manner as in Example 1 except that the content of the liquid epoxy and the polymer resin of the second adhesive layer was adjusted to a ratio of 30:70. .

Comparative Example 2

In the adhesive film manufacturing process of Example 1, a multilayer film adhesive film was prepared in the same manner as in Example 1 except that the content of the liquid epoxy and the polymer resin of the first adhesive layer was adjusted in a ratio of 30:70. .

Experimental Example 1

Peeling force A: ASTM3330 deformation and measurement value is very small, the width of the measurement sample was 4 inches, divided by 4 was data. In a constant temperature and humidity condition, the first adhesive layer was attached to the glass by 4inch three by roller, and then 180 degree Peel was measured using a TA device.

Peeling force B: ASTM3330 After attaching the second adhesive layer to the glass 1 inch by 3 rollers in a constant temperature and humidity conditions 180 degrees Peel was measured using a TA machine.

Peeling force C: ASTM3330 After attaching the first adhesive layer to the glass through a laminator heated at 60 degrees for 3 units at 1 inch in constant temperature and humidity conditions, the adhesive force between the adhesive layer itself and the glass was measured at 180 degrees using a TA device. It was.

Table 1 division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Peel A 2.1 2.7 2.4 2.1 1.2 Peel force B 13.6 15.2 16.9 7.0 13.6 Peel force C 29.8 40.3 38.0 29.8 28.9 Defective rate when peeling off protective film 0.2% 0.1% 0.1% 25.8% 0.1% Defective rate when peeling release film 0.4% 0.1% 0.2% 0.1% 1.5%

Claims (16)

Protective film; A first adhesive layer formed on the protective film; A second adhesive layer formed on the first adhesive layer; And a release film formed on top of the second adhesive layer, An adhesive film for encapsulating an organic electronic device, wherein the first adhesive layer and the second adhesive layer satisfy the following general formula 1: [Formula 1] C> B> A Where A represents the peel force between the first adhesive layer and the protective film, B represents the peel force between the second adhesive layer and the release film, C is the peel force between the first adhesive layer and the encapsulation substrate after the protective film is removed. The adhesive film for encapsulating an organic electronic device according to claim 1, wherein the first adhesive layer and the second adhesive layer satisfy the following general formula (2): [Formula 2] B-A ≥ 5 gf / 25mm The adhesive film for encapsulating an organic electronic device according to claim 1, wherein the first adhesive layer and the second adhesive layer satisfy the following general formula (3): [Formula 3] C-B ≥ 16 gf / 25mm The adhesive film for encapsulation of an organic electronic device according to claim 1, wherein at least one of the first adhesive layer and the second adhesive layer comprises a moisture adsorbent and / or a filler component. The adhesive film for encapsulating an organic electronic device according to claim 1, wherein the first adhesive layer or the second adhesive layer comprises an acrylic resin, a polyester resin, an isocyanate resin, or an epoxy resin. The adhesive film for encapsulation of an organic electronic device according to claim 5, wherein the first adhesive layer or the second adhesive layer further comprises a surface additive. The adhesive film for encapsulating an organic electronic device according to claim 6, wherein the surface additive is a vinyl, amino, epoxy, methacryroxine silane coupling agent, polyester modified acrylic, polyurethane or acrylic resin. The adhesive film for sealing an organic electronic device according to claim 5, wherein the first adhesive layer further comprises a polymer resin having a softening point of 40 ° C or higher. The adhesive film for encapsulating an organic electronic device according to claim 8, wherein the polymer resin is a resin having a weight average molecular weight of 20,000 or more. The adhesive film of claim 9, wherein the polymer resin is one or a mixture of two or more selected from the group consisting of a phenoxy resin, an acrylate resin, an epoxy resin, a polar functional group-containing rubber, and a polar functional group-containing reactive rubber. Peeling the protective film from the adhesive film of claim 1; Attaching the first adhesive layer to the encapsulation substrate; Peeling off the release film; And And laminating the second adhesive layer to be in contact with the organic electronic device. The method of claim 11, wherein the attaching of the first adhesive layer to the encapsulation substrate is performed by attaching the Big C force between the first adhesive layer and the encapsulation substrate and the peel force B between the second adhesive layer and the release film to satisfy the following general formula (3). Sealing method of organic electronic device: [Formula 3] C-B ≥ 16 gf / 25mm The method of claim 11, wherein the attaching the first adhesive layer to the encapsulation substrate comprises laminating the first adhesive layer to the encapsulation substrate at 40 ° C. to 100 ° C. 13. The method of encapsulating the organic electronic device according to claim 13, wherein the second adhesive layer is laminated so as to cover the entire surface of the organic electronic device. Board; An organic electronic element formed on the substrate, and an adhesive film encapsulating the organic electronic element, The adhesive film includes an first adhesive layer and a second adhesive layer of claim 1. The organic electronic device according to claim 15, wherein the second adhesive layer of the adhesive film covers the entire surface of the organic electronic device.

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