WO2012148071A2 - Adhesive film for an organic el device, composition included therein, and organic el display device including same - Google Patents

Abstract

The present invention relates to an adhesive film for an organic EL device, to a composition included therein, and to an organic EL display device including same.

Description

Adhesive film for organic EL elements, composition contained therein, and organic EL display device comprising same

The present invention relates to an adhesive film for an organic EL device, a composition contained therein, and an organic EL display device including the same.

An organic EL element is a polycrystalline semiconductor device, is used in backlights of liquid crystals and the like to obtain high luminance light emission at low voltage, and is expected to be a thin flat display device. However, the organic EL element is extremely weak in moisture, the interface between the metal electric field and the organic EL layer may be peeled off due to the influence of moisture, the metal may be oxidized and become highly resistant, and the organic material itself may be deteriorated by moisture. Therefore, there is a problem that light is not emitted and luminance is lowered.

In order to solve such a problem, the method of sealing an organic electroluminescent element with a curable composition is developed. Background Art A method of molding an organic EL element into an acrylic resin by a conventional sealing method, a method of blocking an organic EL element from moisture by adding a moisture absorbent to the sealing resin of the organic EL element, and the like have been proposed.

However, the conventional method of encapsulating the organic EL device has a limitation in suppressing the occurrence and growth of dark spots, it cannot have sufficient adhesive force, and it cannot fully satisfy all the requirements for encapsulation of the organic EL device. There was a limit to use for encapsulation. In particular, the organic EL device has a disadvantage in that it is very sensitive to moisture and easily decomposes, causing chemical reaction with moisture. However, the curable composition used for the sealing application of the existing organic EL device has a limit in lowering the water transmittance.

In addition, high temperature heat is provided in the thermosetting process during the encapsulation process of the organic EL element. Therefore, when the thermal expansion coefficient of the sealing composition is large, the adhesive layer may bend or peeling may occur between the organic EL element and the substrate.

SUMMARY OF THE INVENTION An object of the present invention is to provide an adhesive film for an organic EL device comprising an adhesive layer having a low thermal expansion rate, a composition included therein, and an organic EL display device including the same.

Another object of the present invention is to provide an adhesive film for an organic EL device comprising an adhesive layer having a low water transmittance, a composition included therein, and an organic EL display device including the same.

It is still another object of the present invention to provide an adhesive film for an organic EL device, a composition included therein, and an organic EL display device including the adhesive layer having a good coating film state and having good adhesion and high usability.

An adhesive film for an organic EL device, which is an aspect of the present invention, includes an adsorbent and may be cured at 90 ° C. for 2 hours, and then have a moisture transmittance of about 100 g / m ² · day or less at 50 ° C. and 100% relative humidity. .

In one embodiment, the adsorbent may be included in about 0.5-40% by weight based on solids in the adhesive film.

In one embodiment, the adsorbent may include one or more selected from the group consisting of zeolite, calcium oxide, molecular sieve, activated carbon, silica gel and the like.

In one embodiment, the adhesive film may further include an epoxy resin, a film former resin, and a curing agent having a weight average molecular weight of about 50-10,000 g / mol.

In one embodiment, the film former resin may be included in an amount of about 50-240 parts by weight based on 100 parts by weight of an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol.

In one embodiment, the adhesive film may further include one or more selected from the group consisting of a silane coupling agent, a filler, a leveling agent, an antifoaming agent, a storage stabilizer, a plasticizer and a talc adjusting agent.

Another aspect of the present invention is an organic EL display device comprising: a first substrate having an organic EL element formed on one surface thereof; A second substrate spaced apart from the first substrate; And a substrate disposed between the first substrate and the second substrate to bond the first substrate and the second substrate, the cured at 90 ° C. for 2 hours, and then the water transmittance at about 50 ° C. and 100% relative humidity of about 100 g / It may include an adhesive layer that is m ² · day or less.

Another aspect of the present invention is an organic EL display device comprising: a first substrate having an organic EL element formed on one surface thereof; A second substrate spaced apart from the first substrate; And an adhesive layer disposed between the first substrate and the second substrate to bond the first substrate and the second substrate and having a thermal expansion rate of about 0 ° C. to 100 ° C. of about 100 ppm / ° C. or less.

In one embodiment, the adhesive layer may be cured for 2 hours at 90 ℃ and the water transmittance at about 50 ℃ and 100% relative humidity may be about 100g / m ² · day or less.

In one embodiment, the adhesive layer may include a plate-shaped filler.

In one embodiment, the adhesive layer may further include an epoxy resin, a film former resin, and a curing agent having a weight average molecular weight of about 50-10,000 g / mol.

In one embodiment, the adhesive layer may further include a silane coupling agent.

Another aspect of the present invention, the adhesive composition for encapsulating an organic EL device includes (A) a plate-shaped filler, (B) an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol, (C) a film-forming resin, and (D) It may include a curing agent.

The present invention provides an adhesive film for an organic EL device comprising an adhesive layer having a low water transmittance. This invention provided the adhesive film for organic electroluminescent elements containing the adhesive layer in the state of a favorable coating film, and the adhesive force is high and usability is high. The present invention provides an organic EL display device comprising an adhesive layer composed of the adhesive film for organic EL elements. The present invention provides an organic EL display device including an adhesive layer having a low thermal expansion rate and a low water transmittance. In addition, the present invention provides an organic EL display device having an adhesive layer having a good coating film state and having good adhesion and high usability.

1 shows an organic EL display device according to an embodiment of the present invention.

One aspect of the present invention relates to an adhesive film for an organic EL device.

The film of the present invention may be cured at 90 ° C. for 2 hours, and then the water transmittance in the film thickness direction may be about 100 g / m ² · day or less at 50 ° C. and 100% relative humidity. Within this range, the water barrier effect is high, and peeling of the glass or film substrate on which the organic EL element is formed and the organic EL element can be prevented. Moisture permeability may preferably be greater than about 0 up to 100 g / m ² · day at 50 ° C. and 100% relative humidity, more preferably greater than about 50 g / m ² · day up to 50 ° C. and 100% relative humidity. have.

Moisture permeability can be measured with a film having a thickness of 20-30 μm. First, the composition constituting the adhesive film is filmed to the thickness and cured at 90 ° C. for 2 hours, and then measured by MOCON test using carrier gas as nitrogen gas under 50 ° C., 100% relative humidity, and 760 mmHg pressure. This is not restrictive. After curing, the adhesive film may have a thickness of about 20 μm-30 μm.

In one embodiment, the adhesive film may include an adsorbent. The adsorbent can block the contact between the organic EL element and water by providing hygroscopicity by physical adsorption.

The adsorbent preferably uses particles that are porous such that the surface area adsorbed per unit volume or unit weight is wide to provide effective hygroscopicity. The adsorbent preferably has an average pore size of about 1 nm-20 nm.

The adsorbent preferably has a particle size (D50) of about 50 nm-5 μm. Within this range, the hygroscopic effect is good and the film formability does not deteriorate. The adhesive film may comprise an adsorbent having two or more particle sizes.

The adsorbent may include one or more selected from the group consisting of zeolite, calcium oxide, molecular sieve, activated carbon, silica gel and the like, but is not limited thereto.

The adsorbent may be included in about 0.5-40% by weight of the adhesive film on a solids basis. Within this range, the hygroscopic effect is good and the film formability does not deteriorate. Preferably about 4-20% by weight.

The adsorbent may be included in an amount of about 10-150 parts by weight based on 100 parts by weight of an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol described below. Within this range, the hygroscopic effect may be good and the film formability does not deteriorate and the adhesive force may have a high effect. Preferably about 15-50 parts by weight.

In another embodiment, the adhesive film may further include, in addition to the adsorbent, an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol, a film former resin, and a curing agent.

The epoxy resin may have a weight average molecular weight of about 50-10,000 g / mol. Within this range, the adhesion of the film may be enhanced and the coating properties may be imparted. The weight average molecular weight may preferably be about 100-5,000 g / mol, more preferably about 200-4,000 g / mol. In addition, the epoxy resin preferably has about 700 ppm or less of hydrolyzable chlorine ions. Within this range, there may be an effect that does not damage the device in the acceleration reliability test for long-term reliability evaluation. The chlorine ion may preferably be about 0-500 ppm, more preferably about 0-300 ppm.

The epoxy resin is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a hydrogenated bisphenol type epoxy resin, a cycloaliphatic epoxy resin, a naphthalene type epoxy resin, a phenol novolak type epoxy resin, an o-cresol novolak type epoxy It may include, but is not limited to, one or more selected from the group consisting of resins, disclopentadiene type epoxy resins, biphenyl type epoxy resins, biphenyl novolak type epoxy resins, and naphthalene novolak type epoxy resins. .

The epoxy resin may be included in about 20-80% by weight based on the solids of the adhesive layer. Within this range, coating film properties and film formability may be good. Preferably about 20-75% by weight, more preferably about 25-70% by weight, most preferably about 27-59% by weight.

The film-forming resin may be an aromatic resin including an epoxy resin having a weight average molecular weight of about 10,000-500,000 g / mol, a (meth) acrylate resin, a urethane (meth) acrylate resin, a polyimide, a styrene resin, And it may include one or more selected from the group consisting of rubber, including diene-based, silicone-based, urethane-based, fluorine-based rubber and the like. Preferably, the film former resin may be an epoxy resin having a weight average molecular weight of about 10,000-500,000 g / mol. The epoxy resin has an effect of imparting adhesion and coating properties of the film with a room temperature tack within the weight average molecular weight range. Preferably about 70,000-500,000 g / mol.

The epoxy resin having a weight average molecular weight of about 10,000-500,000 g / mol may include a resin having a bisphenol A type or a bisphenol F type epoxy skeleton. For example, it may include, but is not limited to, one or more selected from the group consisting of a solid bisphenol A epoxy resin, a solid bisphenol F epoxy resin, and a phenoxy resin.

The film former resin may be included in about 10-70% by weight based on the solids of the adhesive layer. Within this range, the film formability may be good and the reliability may be good. Preferably about 20-70% by weight, more preferably about 25-70% by weight, most preferably about 25-67% by weight.

The film former resin may include about 40-240 parts by weight based on 100 parts by weight of the epoxy resin having the weight average molecular weight of about 50-10,000 g / mol. Within this range, the film formability may be good and the reliability may be good. Preferably about 50-240 parts by weight, more preferably about 100-150 parts by weight.

The curing agent may include an imidazole series curing agent. The imidazole series curing agent may include an imidazole compound having at least one functional group selected from the group consisting of a phenyl group, 10 or more carbon atoms, preferably 10-20 alkenes, and a cyan group. The imidazole-based curing agent may enable the curing of the film coating film stability, room temperature compatibility and low temperature, especially at a temperature of 90 ° C or less.

The curing agent may include an imidazole curing agent having a reaction initiation temperature of about 60-100 ° C. and an imidazole curing agent having a reaction initiation temperature of about 100-160 ° C. In the present invention, the 'reaction start temperature' means a temperature at which the imidazole curing agent reacts with the epoxy resin to start curing. Preferably, an imidazole curing agent having a reaction initiation temperature of about 70-98 ° C. and an imidazole curing agent having a reaction initiation temperature of about 105-140 ° C. may be included.

Two or more kinds of imidazole curing agents having a reaction initiation temperature of about 60-100 ° C. may be included. In addition, two or more kinds of imidazole curing agents having the reaction initiation temperature of about 100-160 ° C may be included.

The imidazole curing agent having a reaction initiation temperature of about 60-100 ° C. and the imidazole curing agent having a reaction initiation temperature of about 100-160 ° C. are a phenyl group, a benzyl group, one or more carbons, for example, one to twenty carbon alkanes. It may have a cyano group or an amine group.

Examples of the imidazole curing agent having a reaction start temperature of about 60-100 ° C. include 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1 -Benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecyl Imidazole, 2-phenylimidazoline, and the like, but are not limited to these.

Examples of imidazole curing agents having a reaction initiation temperature of about 100-160 ° C. include 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium-trimelitate, 2,4- Diamino-6 [2'-undecylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 1-cyanoethyl-2-phenylimidazolium-trimelitate, 2-phenylimidazole isocyanuric acid adduct, 1-benzyl-2- Phenylimidazole hydrobromide and the like, but are not limited thereto.

 The curing agent may be included in about 0.1-10% by weight based on the solids of the adhesive film. Within this range, the film formability may be good and the reliability may be good. Preferably about 1-10% by weight, more preferably about 1-5% by weight.

Further, the curing agent is about 0.1-20 parts by weight, preferably about 0.5-10 parts by weight, more preferably about 1-7 parts by weight of 100 parts by weight of the epoxy resin having the weight average molecular weight of about 50-10,000 g / mol. It may be included in parts by weight.

In another embodiment, the adhesive layer may further include one or more selected from the group consisting of a silane coupling agent and a filler. The silane coupling agent and the filler may increase the properties and reliability of the film coating film.

The silane coupling agent may use a conventional coupling agent. For example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltri Methoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyl Selected from the group consisting of trimethoxysilane, vinyltrimethoxysilane, N-2- (vinylbenzylamino) ethyl) -3-aminopropyltrimethoxysilane hydrochloride and 3- (meth) acryloxypropyltrimethoxysilane One or more species may be used, but is not limited thereto. The silane coupling agent may be included in an amount of about 0.1-20 parts by weight based on 100 parts by weight of the epoxy resin having a weight average molecular weight of about 50-10,000 g / mol.

The filler may be a conventional filler. For example, one or more selected from the group consisting of aluminum oxide, aluminum silicate, talc and plate silicates may be used, but is not limited thereto. The filler may be included in about 1-150 parts by weight, preferably about 10-100 parts by weight, based on 100 parts by weight of the film-forming resin, based on solids.

In another embodiment, the adhesive layer may further include one or more additives. The additive can improve the leveling and coating properties on the surface. The additive may be used, for example, but not limited to one or more selected from the group consisting of a leveling agent, an antifoaming agent, a storage stabilizer, a plasticizer and a talc adjusting agent.

The adhesive film can be produced by drying and laminating an adhesive composition for sealing an organic EL device described below. Drying and laminating methods are not particularly limited but may include a method of drying at about 20-80 ° C. to about 0.2 m / s-1.5 m / s.

The adhesive film may have a thickness of about 1-100 μm, more preferably about 10-50 μm. Within this range, the organic EL device and the sealing film can be adhered well.

Another aspect of the present invention relates to a resin composition for sealing an organic EL device.

The composition is present in the form of a film exhibiting non-fluidity at 25 ℃ and when heated to 50-100 ℃ to express the fluidity and adhesiveness between the organic EL element formed on the glass or film substrate and the sealing glass or film substrate between can do.

Form an organic EL device consisting of a transparent electrode, a hole transport layer, an organic EL layer and a back electrode on a glass or film substrate, heat transfer the composition of the present invention thereon, and heat-transfer the non-permeable glass or film to bond and encapsulate it. Can be. Alternatively, the composition of the present invention may be thermally transferred to a water-impermeable glass or film, and bonded and sealed while heating to a glass or film on which an organic EL element is formed.

More specifically, a transparent electrode is formed to a thickness of about 0.1 mu m on a glass or film substrate. In the film formation of a transparent electrode, there is a method by vacuum deposition and sputtering. A hole transporting layer and an organic EL layer are sequentially formed on the transparent electrode at a thickness of about 0.05 μm, respectively, and a back electrode is formed on the organic EL layer at a thickness of about 0.1-0.3 μm. The composition of the present invention is transferred to a laminate or the like on top of the glass or film substrate which has finished film formation of the device. At this time, when the composition of the present invention is transferred to a release film to form a sheet can be easily transferred. Then, a non-permeable glass or film substrate is superimposed on top of the transferred composition. This is heat-compression-bonded using a vacuum laminator apparatus to preliminarily fix the lower glass or film substrate and the upper non-permeable glass or film substrate. Then, the thermosetting resin is completely cured at a curing temperature, for example, about 90 ° C. or less. It is also possible to transfer the composition of the present invention to the above impervious glass or film substrate first and to polymerize the element substrate on which the organic EL layer is formed.

The composition of the present invention may have a shelf life of at least about 7 days at about 25 ℃.

The film or cured product layer prepared from the composition of the present invention preferably has a thickness of about 1-100 μm, more preferably about 10-50 μm. It is possible to easily bond between two sheets of glass or film within the above range.

The composition may include (A) an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol, (B) film former resin, (C) adsorbent, and (D) hardener. The content about said component (A)-(D) is as having mentioned above.

The composition may further include one or more selected from the group consisting of the silane coupling agent and the filler described above, and may further include one or more of the additives described above.

The composition may include a solvent commonly used in the art, for example, methyl ethyl ketone. Solvents may be included in the balance in the composition.

Another aspect of the present invention relates to an organic EL display device. The apparatus includes a first substrate having an organic EL element formed on one surface thereof;

A second substrate spaced apart from the first substrate; And

Disposed between the first substrate and the second substrate to bond the first substrate and the second substrate, and cured at 90 ° C. for 2 hours, and then a water transmittance of about 100 g / m at 50 ° C. and 100% relative humidity. It may contain an adhesive layer of ² · day or less.

Referring to FIG. 1, an organic EL display device 1 according to an embodiment of the present invention may include a first substrate 2, an organic EL element 3, a second substrate 4, and an adhesive layer 5. Can be.

After the adhesive layer is cured at 90 ° C. for 2 hours, the moisture transmittance in the adhesive layer thickness direction may be about 100 g / m ² · day or less at 50 ° C. and 100% relative humidity. Within this range, the water barrier effect is high and the peeling of the first substrate and the organic EL element can be prevented. Moisture permeability may preferably be greater than about 0 and less than 50 g / m ² · day at 50 ° C. and 100% relative humidity.

The adhesive layer may include the adhesive film for organic EL device or the adhesive composition for encapsulating the organic EL device described above.

The adhesive layer may have a thickness of about 1-100 μm, more preferably about 10-50 μm. Within this range, the organic EL device and the sealing film can be adhered well.

The first substrate may be made of a material such as a transparent glass, a film, a plastic sheet, a silicon or metal substrate, and may have a flexible or non-flexible characteristic and a transparent or non-transparent characteristic. One or more organic EL elements are formed on one surface of the first substrate. The organic EL element is composed of a transparent electrode, a hole transport layer, an organic EL layer and a back electrode.

The second substrate may be disposed on the organic EL element, spaced apart from the first substrate, and adhered to the first substrate by the adhesive layer. As the second substrate, not only a glass material substrate but also a substrate having excellent barrier properties such as a plastic sheet on which metal is laminated may be used.

A getter 6 may be formed between the first substrate and the second substrate and on the side of the organic EL element to adhere the first substrate and the second substrate.

Another aspect of the present invention relates to an organic EL display device. The apparatus includes a first substrate having an organic EL element formed on one surface thereof;

A second substrate spaced apart from the first substrate; And

The substrate may be disposed between the first substrate and the second substrate to bond the first substrate to the second substrate, and may include an adhesive layer having a thermal expansion rate of about 100 ppm / ° C. or less from 0 ° C. to 100 ° C.

Referring to FIG. 1, an organic EL display device 1 according to an embodiment of the present invention may include a first substrate 2, an organic EL element 3, a second substrate 4, and an adhesive layer 5. Can be.

The adhesive layer may have a thermal expansion rate of about 100 ppm / ° C. or less in a temperature range of 0 ° C. to 100 ° C. Within this range, the adhesive layer does not bend even under high temperature curing conditions accompanying the sealing process of the organic EL element, and the first substrate and the organic EL element are not misaligned. Preferably the coefficient of thermal expansion may be greater than about 0 up to 100 ppm / ° C., more preferably greater than about 0 up to 51 ppm / ° C.

The coefficient of thermal expansion may be measured with an adhesive layer having a length of 8.0 ± 0.5 mm × width 4.8 ± 0.2 mm × thickness 0.2 ± 0.1 mm. First, the composition constituting the adhesive layer is filmed and laminated, and cured at 90 ° C. for 2 hours, and then cut into a length of 8.0 ± 0.5mm × width 4.8 ± 0.2mm × thickness 0.2 ± 0.1mm and a thermomechanical analyzer (TMA, Thermal expansion coefficient was measured using Thermal Mechanical Apparatus). The sample was hooked to a quartz hook and subjected to a force of 0.05 N and then heated to 10 ° C./min from −30 ° C. to 250 ° C. under a nitrogen atmosphere. The thermal expansion coefficient calculated | required the value of the temperature range from 0 degreeC to 100 degreeC.

In one embodiment, the adhesive layer is cured at 90 ℃ for 2 hours, the water transmittance in the adhesive layer thickness direction may be about 100g / m ² · day or less at 50 ℃ and 100% relative humidity. Within this range, the water barrier effect is high and the peeling of the first substrate and the organic EL element can be prevented. Moisture permeability may preferably be greater than about 0 up to 100 g / m ² · day at 50 ° C. and 100% relative humidity, more preferably greater than about 50 g / m ² · day up to 50 ° C. and 100% relative humidity. have.

Moisture permeability can be measured with an adhesive layer having a thickness of about 20-30 μm. First, the composition constituting the adhesive layer is filmed to the thickness, and cured at 90 ° C. for 2 hours, and then measured by MOCON test using carrier gas as nitrogen gas under 50 ° C., 100% relative humidity, and 760 mmHg pressure. It is not limited. After curing, the adhesive layer may have a thickness of about 10-50 μm, preferably about 20-30 μm.

In one embodiment, the adhesive layer may include a plate-shaped filler.

The plate-shaped filler does not impart hygroscopicity by physical adsorption or chemical bonding or hygroscopicity by chemical bonding. However, the plate-shaped filler may not only prevent the adhesive layer having a form such as a film from expanding under heat as a plate-like form, but also block moisture's movement path or increase its length to impart hygroscopicity. have.

The plate-shaped filler may comprise a plate-like structure having a size of about 50 nm-10 μm in length, about 50 nm-10 μm in width, and about 50 nm-10 μm in thickness. Within this range, the coefficient of thermal expansion may be low, the moisture permeability may be low, and film forming may be good.

The plate-shaped filler is not particularly limited as long as it is a plate-shaped structure, but may include, for example, one or more selected from the group consisting of talc, mica, plate silicate, graphite and clay.

The plate-shaped filler may be included at about 0.5-40% by weight based on solids in the adhesive layer. Within this range, the moisture permeability may be low to have a moisture proof effect, and the film formability does not deteriorate. Preferably about 4-20% by weight.

The plate-shaped filler may be included in an amount of about 10-80 parts by weight based on 100 parts by weight of the epoxy resin having a weight average molecular weight of about 50-10,000 g / mol. Within this range, the hygroscopic effect may be good and the film formability does not deteriorate and the adhesive force may have a high effect. Preferably about 15-50 parts by weight.

In another embodiment, the adhesive layer may further include an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol, a film former resin, and a curing agent, in addition to the plate-shaped filler.

Details of the epoxy resin having the weight average molecular weight of about 50-10,000 g / mol are as described above. The epoxy resin may be included in about 20-80% by weight based on the solids of the adhesive layer. Within this range, coating film properties and film formability may be good. Preferably about 20-65% by weight, more preferably about 27-63% by weight.

Details of the film-forming resin are as described above. The film former resin may be included in about 10-70% by weight based on the solids of the adhesive layer. Within this range, the film formability may be good and the reliability may be good. Preferably about 20-70% by weight, more preferably about 25-67% by weight.

The film former resin is about 40-240 parts by weight, preferably about 100-200 parts by weight, more preferably about 100- parts by weight, based on 100 parts by weight of the epoxy resin having the weight average molecular weight of about 50-10,000 g / mol. It may be included in 150 parts by weight.

Details of the curing agent are as described above. The curing agent may be included in about 0.1-10% by weight based on solids of the adhesive layer. Within this range, the film formability may be good and the reliability may be good. Preferably 1-10% by weight, more preferably about 1-5% by weight.

In addition, the curing agent may be included in about 1-20 parts by weight, preferably about 1-10 parts by weight, more preferably about 1-5 parts by weight based on 100 parts by weight of the film-forming resin.

In another embodiment, the adhesive layer may further include a silane coupling agent. The silane coupling agent may increase the properties and reliability of the film coating film. Details of the silane coupling agent are as described above. The silane coupling agent may be included in an amount of about 0.1-20 parts by weight based on 100 parts by weight of the epoxy resin having a weight average molecular weight of about 50-10,000 g / mol.

In another embodiment, the adhesive layer may further include one or more additives. Details of the additives are as described above.

The adhesive layer can be produced by drying and laminating an adhesive composition for sealing an organic EL device described below. Drying and laminating methods are not particularly limited but may include a method of drying at about 20-80 ° C. to about 0.2 m / s-1.5 m / s.

The adhesive layer may have a thickness of about 1-100 μm, more preferably about 10-50 μm. Within this range, the organic EL device and the sealing film can be adhered well.

Details of the first substrate and the second substrate are as described above. A getter 6 may be formed between the first substrate and the second substrate and on the side of the organic EL element to adhere the first substrate and the second substrate.

Another aspect of the present invention relates to an adhesive composition for sealing an organic EL device.

The composition may be present on a film exhibiting non-flowability at 25 ° C. and heated at 50-100 ° C. to express fluidity and adhesiveness to encapsulate between the organic EL element formed on the first substrate and the second substrate. .

An organic EL element composed of a transparent electrode, a hole transport layer, an organic EL layer, and a back electrode can be formed on the first substrate, and the composition of the present invention can be thermally transferred, bonded to the second substrate, and joined to be sealed. Alternatively, the composition of the present invention can be thermally transferred to a second substrate, and bonded to and sealed with a first substrate on which an organic EL element is formed.

More specifically, a transparent electrode is formed to a thickness of about 0.1 mu m on the first substrate. In the film formation of a transparent electrode, there is a method by vacuum deposition and sputtering. A hole transport layer and an organic EL layer are sequentially formed on the transparent electrode at a thickness of about 0.05 μm, respectively, and a back electrode is formed on the organic EL layer at a thickness of about 0.1-0.3 μm. The composition of the present invention is transferred to a laminate or the like on top of the glass or film substrate which has finished film formation of the device. At this time, when the composition of the present invention is transferred to a release film to form a sheet can be easily transferred. Then, the second substrate is superimposed on top of the transferred composition. This is heat-compression-bonded using a vacuum laminator apparatus, and the lower 1st board | substrate and the upper 2nd board | substrate are pre-fixed. Then, the thermosetting resin is completely cured at a curing temperature, for example, about 90 ° C. or less. It is also possible to transfer the composition to the second substrate first and polymerize the first substrate on which the organic EL layer is formed.

The composition may have a shelf life of 7 days or more at 25 ℃.

The film or cured product layer prepared from the composition may have a thickness of about 1-100 μm, more preferably about 10-50 μm. It is possible to easily bond between two sheets of glass or film within the above range.

The composition may include (A) a plate-shaped filler, (B) an epoxy resin having a weight average molecular weight of about 50-10,000 g / mol, (C) film former resin, and (D) hardener. Details of the above components (A) to (D) are as described above.

The plate-shaped filler may be included in about 0.5-40% by weight based on solids of the composition. Within this range, room temperature stability may be good and film formability may be good. Preferably about 4-20% by weight.

The epoxy resin having a weight average molecular weight of about 50-10,000 g / mol may be included in an amount of about 20-80 wt% based on the solids content of the composition. Within this range, coating film properties and film formability may be good. Preferably about 20-65% by weight, more preferably about 27-63% by weight.

The film former resin may be included in about 10-70% by weight based on solids of the composition. Within this range, the film formability may be good and the reliability may be good. Preferably about 20-70% by weight, more preferably about 25-67% by weight.

The curing agent may be included in about 0.1-10% by weight based on solids of the composition. Within this range, the film formability may be good and the reliability may be good. Preferably about 1-10% by weight, more preferably about 1-5% by weight.

The composition may further comprise the silane coupling agent described above, and may further comprise one or more of the additives described above.

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. However, this is presented as a preferred example of the present invention and in no sense can be construed as limiting the present invention.

Details that are not described herein will be omitted since those skilled in the art can sufficiently infer technically.

Specific specifications of the components used in the following Examples and Comparative Examples are as follows.

(1) YDF-8170 (TOHTO) (epoxy equivalent 159 g / g-eq., Mw. 318 g / mol) was used as an epoxy resin having a weight average molecular weight of 50-10,000 g / mol.

(2) E-4275 (JER) (Mw. 74,000 g / mol), an epoxy resin having a weight average molecular weight of 10,000-500,000 g / mol, was used as the film-forming resin.

(3) Zeolite (Aldrich) was used as the adsorbent.

(4) D-1000 (Nippon talc) was used as a plate-shaped filler.

(5) As a curing agent, 2P4MZ (Shikoku) (2-phenyl-4-methylimidazole), which is a curing agent 1, and 2P4MHZ (Shikoku) (2-phenyl-4-methyl-5-hydoxymethylimidazole), which was a curing agent 2, were used.

Example 1-4

The film-forming resin was dispersed in methyl ethyl ketone and the solid content was mixed in the amount shown in Table 1 below. Then, an epoxy resin, an adsorbent, and a curing agent having a weight average molecular weight of 50-10,000 g / mol were added in the amounts shown in Table 1 below. Dispersion was carried out using a planetary mixer and a 3-roll mill. A coating film was formed with an applicator, dried and laminated to prepare an adhesive film having a thickness of 20 μm.

Example 5-8

The film-forming resin and the plate-shaped filler were dispersed in methyl ethyl ketone, respectively, and the solids were mixed in the amounts shown in Table 2 below. Then, the obtained solution was mixed and an epoxy resin and a curing agent were added in the amounts shown in Table 2 below. Dispersion was carried out using a planetary mixer and a 3-roll mill. A coating film was formed with an applicator, dried and laminated to prepare an adhesive layer having a thickness of 20 μm.

Comparative Example 1

In Example 1-4, except that the weight average molecular weight of 50-10,000 g / mol epoxy resin, film former resin, adsorbent, curing agent was changed to the content shown in Table 1 below, the same method was carried out to a thickness of 20 A micrometer adhesive film was prepared.

Comparative Example 2

An adhesive layer having a thickness of 20 μm was prepared in the same manner as in Example 5-8, except that the epoxy resin, the film former resin, and the curing agent were changed to the contents shown in Table 2 below.

Experimental Example 1: Evaluation of Physical Properties of Adhesive Film

The adhesive films prepared in Examples 1-4 and Comparative Example 1 were used as samples, and the physical properties thereof were evaluated and listed in Table 1 below.

<Measurement of Properties>

(1) Moisture permeability: After heat curing at 90 ℃ for 2 hours, the film was 20㎛ thickness MOCON test using nitrogen gas as a carrier gas under 50 ℃, 100% relative humidity, 760mmHg pressure.

(2) Coating state: It was confirmed whether tack generation and flow of the produced film at 25 ℃. The tack is tack-tested the surface of a film made with a thickness of 20 ㎛ with TOPTAC 2000A of CHEMILAB. When the tack is less than 100gf or no flow at 25 ℃, ○, when the tack exceeds 100gf at 25 ℃ was evaluated as ×.

(3) DSS (die shear strength) after curing: Laminated film (20㎛ thickness 5 ㎛ 5, 5 seconds) to the film thickness of the prepared 20㎛ thick substrate and cured for 2 hours at 100 ℃ DAGE 4000 (DAGE90社) was measured the die shear strength.

(4) DSS after reliability evaluation: After maintaining the sample prepared in the same manner as the measurement method (3) above at 85 ℃ and 85% relative humidity for 24 hours, the die shear strength was measured by DAGE 4000.

(5) Tensile strength: The film was cured at 100 ° C. for 2 hours, and then measured by UTM tensile strength measuring method for a film having a width of 8 mm and a thickness of 20 μm.

(6) Film usability: When it can be used for organic electroluminescent element sealing use, it evaluated as (circle), (triangle | delta) when it can be used partially, and × when it cannot use.

Table 1

		Example 1	Example 2	Example 3	Example 4	Comparative Example 1
Epoxy resin with a weight average molecular weight of 50-10,000 g / mol (parts by weight)		100	100	100	100	100
Film former resin (weight part)		100	100	50	240	100
Adsorbent (part by weight)		15	50	15	15	-
Curing agent (part by weight)	Curing agent 1	One	One	One	One	One
	Hardener 2	4	4	4	4	4
Moisture permeability (g / m 2 · day)		37	29	36	43	378
Coating state		○	○	○	○	○
DSS after hardening (kgf)		76	72	80	64	73
DSS (kgf) after reliability evaluation		63	69	68	48	52
Tensile Strength (N / mm 2 )		24.1	23.6	23.9	19.8	21.3
Availability		○	○	○	○	×

As shown in Table 1, the film containing the adsorbent of the present invention compared to the film not containing the adsorbent has a low moisture permeability, a good coating state, good adhesion and high usability as a film (Comparative Example 1 Reference).

Experimental Example 2: Evaluation of Physical Properties of Adhesive Film

The adhesive films prepared in Examples 5-8 and Comparative Example 2 were used as samples, and physical properties thereof were evaluated, and are shown in Table 2 below.

<Measurement of Properties>

(1) Thermal expansion rate: First, the composition constituting the adhesive layer is filmed, laminated, and cured at 90 ° C. for 2 hours, and then cut into 8.0 ± 0.5 mm in length x 4.8 ± 0.2 mm in width x 0.2 ± 0.1 mm in thickness, followed by a thermal system Thermal expansion coefficient was measured using an analytical measuring device (TMA, Thermal Mechanical Apparatus). The sample was hooked to a quartz hook and subjected to a force of 0.05 N and then heated to 10 ° C./min from −30 ° C. to 250 ° C. under a nitrogen atmosphere. The thermal expansion coefficient calculated | required the value of the temperature range from 0 degreeC to 100 degreeC.

(2) Moisture permeability: After heat curing at 90 ℃ for 2 hours, the MOCON test using a nitrogen gas as a carrier gas under a pressure of 50 ℃, 100% relative humidity, 760mmHg for a film of 20㎛ thickness.

(3) Tensile strength: The film was cured at 90 ° C. for 2 hours and then measured by UTM tensile strength measuring method for a film having a width of 8 mm and a thickness of 20 μm.

(4) Coating state: It was confirmed whether the tack generation and flow of the produced film at 25 ℃. The tack is tack-tested the surface of a film made with a thickness of 20 ㎛ with TOPTAC 2000A of CHEMILAB. When the tack is 0gf ~ 70gf at 25 ℃, ○, when the tack is 70gf ~ 150gf at 25 ℃, △, × was evaluated when the tack is greater than 150gf at 25 ℃.

(5) DSS (die shear strength) after hardening: The 20 ㎛ thick film was laminated on a 5 mm x 5 mm glass substrate (adhesive conditions 120 ℃ 5kgf, 5 seconds) and cured for 2 hours at 100 ℃ DAGE 4000 (DAGE社) was measured die shear strength.

(6) DSS after reliability evaluation: After maintaining the sample prepared in the same manner as the measurement method (5) above at 85 ℃ and 85% relative humidity for 24 hours, the die shear strength was measured by DAGE 4000.

(7) Film usability: When it can be used for organic electroluminescent element sealing use, it evaluated as (circle), (triangle | delta) when it can be used partially, and × when it cannot use.

TABLE 2

		Example 5	Example 6	Example 7	Example 8	Comparative Example 2
Epoxy resin with a weight average molecular weight of 50-10,000 g / mol (parts by weight)		100	100	100	100	100
Film former resin (weight part)		100	100	50	240	100
Plate-shaped filler (parts by weight)		15	50	15	15	-
Curing agent (part by weight)	Curing agent 1	One	One	One	One	One
	Hardener 2	4	4	4	4	4
Thermal expansion rate (ppm / ℃)		47	42	46	51	102
Moisture permeability (g / m 2 · day)		38	31	36	47	378
Coating state		○	○	○	○	○
Tensile Strength (N / mm 2 )		25.7	30.2	24.5	21.0	21.3
DSS after hardening (kgf)		75	83	82	69	73
DSS (kgf) after reliability evaluation		66	71	68	51	52
Availability		○	○	○	○	×

As shown in Table 2, it can be seen that the adhesive layer containing the plate-shaped filler of the present invention compared to the adhesive layer not containing the plate-shaped filler has a low thermal expansion and water permeability, a good coating state, good adhesion, and high usability as a film. (See Examples 5-8 and Comparative Example 2.)

While the embodiments of the present invention have been described with reference to the accompanying drawings, examples, and tables, the present invention is not limited to the above embodiments, but may be manufactured in various forms, and in the technical field to which the present invention pertains. Those skilled in the art will understand that the present invention may be embodied in other specific forms without changing to the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

The present invention provides an adhesive film for an organic EL device, a composition contained therein, and an organic EL display device including the same.

Claims (28)

1. Contains an adsorbent,

   An adhesive film for organic EL device having a water vapor transmission rate (WVTR) of about 100 g / m ² · day or less at 50 ° C. and 100% relative humidity after curing at 90 ° C. for 2 hours.
2. The adhesive film for organic EL device according to claim 1, wherein the moisture transmittance is greater than about 0 and less than 50 g / m ² · day.
3. The adhesive film for organic EL device according to claim 1, wherein the adhesive film has a thickness of about 20 μm to 30 μm after curing at 90 ° C. for 2 hours.
4. The adhesive film for an organic EL device according to claim 1, wherein the adsorbent is included in an amount of about 0.5 wt% to 40 wt% based on solids in the adhesive film.
5. The adhesive film for organic EL device according to claim 1, wherein the adsorbent comprises at least one selected from the group consisting of zeolite, calcium oxide, molecular sieve, activated carbon and silica gel.
6. The adhesive film for organic EL device according to claim 1, wherein the adsorbent has an average pore size of about 1 nm-20 nm.
7. The adhesive film for organic EL device according to claim 1, wherein the adsorbent has a particle size of about 50 nm-5 탆.
8. The adhesive film of claim 1, wherein the adhesive film further comprises an epoxy resin, a film former resin, and a curing agent having a weight average molecular weight of about 50 g / mol to 10,000 g / mol.
9. 9. The organic EL according to claim 8, wherein the film former resin is contained in an amount of about 50 parts by weight to 240 parts by weight based on 100 parts by weight of the epoxy resin having the weight average molecular weight of about 50 g / mol-10,000 g / mol. Adhesive film for the device.
10. The method of claim 8, wherein the film-forming resin is an epoxy resin, (meth) acrylate-based resin, urethane (meth) acrylate-based resin, polyimide, having a weight average molecular weight of about 10,000g / mol-500,000g / mol An adhesive film for organic EL devices, characterized by comprising at least one selected from the group consisting of aromatic resins and rubbers.
11. The adhesive film for an organic EL device according to claim 8, wherein the curing agent includes an imidazole curing agent having a reaction initiation temperature of about 60 ° C-100 ° C and an imidazole curing agent having a reaction initiation temperature of about 100 ° C-160 ° C.
12. The adhesive film for organic EL device according to claim 1, wherein the adhesive film further comprises at least one selected from the group consisting of a silane coupling agent, a filler, a leveling agent, an antifoaming agent, a storage stabilizer, a plasticizer and a talc adjusting agent. .
13. A first substrate having an organic EL element formed on one surface thereof;

    A second substrate spaced apart from the first substrate; And

    Disposed between the first substrate and the second substrate to bond the first substrate and the second substrate, and cured at 90 ° C. for 2 hours, and then a water transmittance of about 100 g / m at 50 ° C. and 100% relative humidity. ^The organic electroluminescence display which is ² or less days and contains the adhesive layer containing a moisture absorbent.
14. A first substrate having an organic EL element formed on one surface thereof;

    A second substrate spaced apart from the first substrate; And

    And an adhesive layer disposed between the first substrate and the second substrate to bond the first substrate and the second substrate, wherein the adhesive layer has a thermal expansion coefficient of about 100 ppm / 占 폚 or less from 0 占 폚 to 100 占 폚.
15. The organic EL display device according to claim 14, wherein the coefficient of thermal expansion is greater than about 0 and 51 ppm / ° C or less.
16. 15. The organic EL display device according to claim 14, wherein the adhesive layer is cured at 90 ° C for 2 hours, and then the moisture transmittance in the adhesive layer thickness direction is about 100 g / m ² · day or less at 50 ° C and 100% relative humidity.
17. The organic EL display device according to claim 16, wherein the adhesive layer has a thickness of about 10 µm to 50 µm after curing at 90 ° C. for 2 hours.
18. The organic EL display device according to claim 14, wherein the adhesive layer includes a plate-shaped filler.
19. 19. The organic EL display device according to claim 18, wherein the plate-shaped filler has a length of about 50 nm-10 mu m, a width of about 50 nm-10 mu m, and a thickness of about 50 nm-10 mu m.
20. 19. The organic EL display device according to claim 18, wherein the plate-shaped filler is contained at about 0.5% by weight to 40% by weight based on solids of the adhesive layer.
21. 19. The organic EL display device according to claim 18, wherein the plate-shaped filler comprises at least one selected from the group consisting of talc, mica, plate silicate, graphite and clay.
22. 19. The organic EL display device according to claim 18, wherein the adhesive layer further comprises an epoxy resin, a film former resin and a curing agent having a weight average molecular weight of about 50 g / mol-10,000 g / mol.
23. The organic EL display device according to claim 22, wherein the epoxy resin has a chlorine ion of greater than about 0 to 500 ppm or less.
24. The method of claim 22, wherein the film-forming resin is an epoxy resin, a (meth) acrylate-based resin, a urethane (meth) acrylate-based resin, a polyimide, having a weight average molecular weight of about 10,000 g / mol-500,000 g / mol An organic EL display device comprising at least one selected from the group consisting of aromatic resins and rubbers.
25. The organic EL display device according to claim 22, wherein the curing agent comprises an imidazole curing agent having a reaction initiation temperature of about 60 ° C-100 ° C and an imidazole curing agent having a reaction initiation temperature of about 100 ° C-160 ° C.
26. 23. The organic EL display device according to claim 22, wherein the film former resin is contained in an amount of about 10 wt% to 70 wt% based on solids of the adhesive layer.
27. 19. The organic EL display device according to claim 18, wherein the adhesive layer further comprises at least one selected from the group consisting of a silane coupling agent, a leveling agent, an antifoaming agent, a storage stabilizer, a plasticizer and a talc adjusting agent.
28. The organic EL display device according to claim 13 or 14, wherein the device further comprises a getter.

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