KR20180028865A - Composition for encapsulating organic light emitting diode, encapsulating layer for organic light emitting diode prepared from the same, and organic light emitting diode display comprising the same - Google Patents

Abstract

Provided are a composition for encapsulating an organic light emitting element which can increase light extraction efficiency, an encapsulating layer for the organic light emitting element formed thereby, and an organic light emitting element display device having the same. The composition for encapsulating an organic light emitting element comprises: a binder; a polysilsesquioxane particle; and an initiator. The polysilsesquioxane particle has the average grain diameter not smaller than 0.5 μm and not greater than 3.0 μm, and a difference between a refractive index of the binder and a refractive index of the polysilsesquioxane particle is not smaller than 0.08 and not greater than 0.20.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for encapsulating an organic light emitting device, an organic light emitting device encapsulation layer formed therefrom, and an organic light emitting diode display device including the encapsulation layer. DISPLAY COMPRISING THE SAME}

The present invention relates to a composition for encapsulating an organic luminescent element, an encapsulating layer for an organic luminescent element formed therefrom, and an organic light emitting diode display including the same.

The organic light emitting device may be easily damaged, lost in function, and become unreliable when moisture, oxygen, or the like is infiltrated into the organic light emitting device. Therefore, the organic light emitting element must be sealed with a sealing composition. An organic light emitting diode (OLED) display device includes an organic light emitting device formed on a lower substrate, an upper substrate facing the lower substrate formed on the organic light emitting device, a sealing composition formed between the lower substrate and the upper substrate, , And inhibits the penetration of oxygen.

The organic light emitting element is a self light emitting element. Light emitted from the organic light emitting element is emitted to the outside through the upper substrate or the lower substrate. However, due to the difference in refractive index between the light emitting layer and the substrate of the organic light emitting diode, when the front surface is set to 0 °, the total reflection increases at a certain angle or more, so that the light extraction efficiency decreases from the front to the side. Especially, the short wavelength (blue) light has a large influence on the angle, so that the WAD (white angular dependency) phenomenon may appear which varies in color depending on the angle. Accordingly, attempts have been made to increase the extraction efficiency of light from the organic light emitting element between the light emitting layer and the substrate. For example, a light diffusion layer is additionally provided between the light emitting layer and the substrate to improve the WAD of the organic light emitting element.

However, it is not known that there is a limit in heightening the light extraction efficiency, and that an additional light diffusion layer is required, and that the light diffusion layer suppresses penetration of moisture and oxygen by sealing the conventional organic light emitting device.

The background art of the present invention is disclosed in Japanese Laid-Open Patent Application No. 2014-056287.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a composition for encapsulating an organic luminescent element which can enhance light extraction efficiency of light from an organic luminescent element.

Another object of the present invention is to provide a composition for encapsulating an organic light emitting device, which can seal an organic light emitting device and improve the reliability of the organic light emitting device by moisture and oxygen penetration.

Another object of the present invention is to provide a composition for encapsulating an organic light emitting device, which can be applied to a screen printing method because of its good applicability.

Another object to be solved by the present invention is to provide a composition for encapsulating an organic luminescent element which is free of solvent and can inhibit outgas formation upon curing and inhibit penetration of residual solvent into an organic luminescent device to prevent degradation of device performance .

The composition for encapsulating an organic luminescent element of the present invention comprises a binder, polysilsesquioxane particles and an initiator, wherein the polysilsesquioxane particles have an average particle diameter (D50) of 0.5 m or more and 3.0 m or less, and the refractive index And the refractive index difference of the polysilsesquioxane particle may be 0.08 or more and 0.20 or less.

The organic light emitting element encapsulation layer of the present invention may be formed of the composition for encapsulating an organic light emitting element of the present invention.

The organic electroluminescent display device of the present invention may include the composition for encapsulating an organic luminescent element of the present invention or the encapsulating layer of the organic luminescent element of the present invention.

The present invention provides a composition for encapsulating an organic light emitting device capable of enhancing light extraction efficiency of light emission from an organic light emitting element.

The present invention provides a composition for encapsulating an organic light emitting device, which can increase the reliability of an organic light emitting device by encapsulating an organic light emitting device and penetrating moisture and oxygen.

The present invention provides a composition for encapsulating an organic light emitting device, which can be applied to a screen printing method because of its good applicability.

Disclosed is a composition for encapsulating an organic light emitting device, which is a solvent-free formulation capable of inhibiting the generation of outgassing during curing and inhibiting the penetration of residual solvent into an organic light emitting device to prevent degradation of device performance.

1 is a cross-sectional view of an OLED display according to an embodiment of the present invention.

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

The terms "upper" and "lower" in this specification are defined with reference to the drawings, wherein "upper" may be changed to "lower", "lower" What is referred to as "on" may include not only superposition, but also intervening other structures in the middle. On the other hand, what is referred to as "directly on" or "directly above"

As used herein, "photocurable" means containing a (meth) acryl group as a photocurable functional group.

As used herein, "(meth) acrylic" may mean acrylic and / or methacrylic.

As used herein, the term " substituted or unsubstituted "means not only a specific substituent but also a common substituent which can be recognized by those skilled in the art. For example, "substituted or unsubstituted" as used herein means that at least one hydrogen atom of the functional group is replaced by a group selected from the group consisting of deuterium, halogen (F, Cl, Br or I), a C1 to C10 alkoxy group, , An aryl group of C6 to C30, an arylalkyl group of C7 to C30, a cyano group, a carbonyl group of C2 to C10, or a heteroaryl group of C2 to C30.

Hereinafter, a composition for encapsulating an organic light emitting diode according to an embodiment of the present invention will be described.

The composition for encapsulating an organic light emitting diode according to the present embodiment comprises a binder, polysilsesquioxane particles and an initiator, wherein the polysilsesquioxane particles have an average particle diameter (D50) of 0.5 mu m or more and 3.0 mu m or less, And the refractive index difference of the polysilsesquioxane particle may be 0.08 or more and 0.20 or less.

The composition for encapsulating an organic light emitting diode according to the present embodiment diffuses light having passed through the best light emitting layer having a refractive index of about 1.8 or more from the organic light emitting device through polysilsesquioxane particles having a specific average particle diameter D50, By controlling the refractive index difference of the polysilsesquioxane particles, WAD can be improved and the light extraction efficiency can be increased.

Generally, in order to increase the diffusion efficiency of light, zirconia and titania which are high refractive index particles having a refractive index of about 2.1 or more are generally used in order to increase the refractive index of the sealing layer. However, in the case of sealing compositions comprising zirconia and titania, it has been confirmed that zirconia and titania completely suppress the diffusion of light by totally reflecting light in the particles, thereby lowering the extraction efficiency of light. The composition according to the present embodiment uses polysilsesquioxane particles having a lower refractive index than zirconia and titania, but controls the difference between the average particle size (D50) of the polysilsesquioxane particles and the refractive index difference between the binder and the polysilsesquioxane particles The haze and the total light transmittance of the organic luminescent element encapsulating layer can be increased at the same time. In addition, when applied to the encapsulation of an organic light emitting diode, it is possible to induce irregular reflection instead of total reflection at the interface between the organic light emitting element and the sealing layer, and to suppress the total reflection of light in the particle, thereby improving the WAD of the organic light emitting device, Based on the above.

Further, the present invention is based on the fact that the polysilsesquioxane particles and the binder are included together to suppress the moisture and oxygen penetration when the organic light emitting device is sealed, thereby enhancing the reliability of the organic light emitting device.

The polysilsesquioxane particles are contained in the sealing composition so that the total reflection in the particle is suppressed while irregularly reflecting the light emitted from the organic light emitting element and the extraction efficiency of light relative to zirconia and titania having a relatively high refractive index can be remarkably increased. Since the refractive index of the polysilsesquioxane particles should be lower than that of the binder in order to increase the light extraction efficiency as described below, an alkyl group having 1 to 5 carbon atoms such as a methyl group may include polyalkylsilsesquioxane particles connected to silicon have. For example, the polysilsesquioxane particles may comprise polymethylsilsesquioxane (PMSQ) particles. In particular, the polymethylsilsesquioxane particles have a lower refractive index than the fluorene-based photo-curable resin among the binders, and thus can increase the light diffusion efficiency.

The polysilsesquioxane particles are optically transparent spherical particles having an average particle diameter (D50) of 0.5 mu m or more and 3.0 mu m or less. In the above range, it can be included in the sealing layer of the organic light emitting element, and the total extraction in the particle can be suppressed, and the light extraction efficiency can be enhanced. The size distribution of the polysilsesquioxane particles used was measured in terms of volume% according to particle diameter (unit: 탆) of a particle analyzer (Multisizer 3). The "average particle diameter (D50)" may mean a value corresponding to D50 when measured according to the above conditions.

Particularly, since the polysilsesquioxane particles have an average particle diameter (D50) of not less than 0.5 mu m and not more than 3.0 mu m, the average particle diameter of zirconia and titania is relatively large, thereby suppressing total internal reflection of light emitted from the organic light- . Preferably, the polysilsesquioxane particles may have an average particle diameter (D50) of 0.5 mu m or more and 2.0 mu m or less. In the above range, it can be included in the sealing layer, and the light extraction efficiency can be enhanced by suppressing total internal reflection within the particle. The polysilsesquioxane particles may be prepared by conventional methods or may include commodities sold commercially.

The average particle diameter (D10) of the polysilsesquioxane particles is 1.0 占 퐉, preferably the average particle diameter (D50) is 1.0 占 퐉, the average particle diameter D10 is 0.45 占 퐉 or more and 1.34 占 퐉 or less, preferably 0.67 占 퐉 or more and 1.12 占 퐉 or less . The polysilsesquioxane particle may have an "average particle diameter (D90)" of 0.75 to 2.23 m, preferably 1.12 to 1.86 m. In the above range, there may be an effect of increasing haze and total light transmittance. The "average particle diameter (D10)" and the "average particle diameter (D90)" may refer to values corresponding to D10 and D90 according to the method described in the "average particle diameter (D50)".

(The refractive index of the binder - the refractive index of the polysilsesquioxane particle) of the polysilsesquioxane particle and the binder is 0.08 to 0.20, preferably 0.10 to 0.20, 0.13 to 0.20, and 0.15 to 0.20 . Thus, the refractive index of the polysilsesquioxane particle is lower than that of the binder. In the above range, the haze and the total light transmittance of the organic light emitting element encapsulation layer can be increased simultaneously, and the efficiency of extracting light having passed through the best light emitting layer having a refractive index of about 1.8 or more after emerging from the organic light emitting element can be increased. At this time, when two or more kinds of binders having different refractive indexes are included, the total refractive index of the binder is defined as a total sum of values obtained by multiplying the weight ratio of the binder among the total binders by the refractive index of the binder.

The polysilsesquioxane particle may have a refractive index of less than 1.5, preferably 1.0 or more and less than 1.5, 1.0 or more and 1.45 or less, and 1.3 or more and 1.43 or less. Within the above range, the diffusion effect of light from the organic light emitting element can be enhanced, the light extraction efficiency can be enhanced, and the refractive index of the binder can easily be controlled.

The polysilsesquioxane particles may be contained in an amount of 1 part by weight or more and 30 parts by weight or less based on 100 parts by weight of the binder. In the above range, when used for encapsulating an organic light emitting device, the haze and total light transmittance can be increased to enhance the extraction efficiency of light. Preferably, the polysilsesquioxane particle is contained in an amount of 5 parts by weight or more and 30 parts by weight or less, 7 parts by weight or more and 30 parts by weight or less, 10 parts by weight or more and 30 parts by weight or less, 10 parts by weight or more and 25 parts by weight Or less and 5 parts by weight or more and 20 parts by weight or less. In the above range, when used for encapsulating an organic light emitting device, the haze and the total light transmittance can be increased simultaneously to further increase the extraction efficiency of light.

The binder may be cured by an initiator to form the organic light emitting element encapsulation layer. The binder is not particularly limited as long as it is a binder capable of providing the refractive index difference with respect to the polysilsesquioxane particle. For example, the refractive index of the binder may be 1.5 or more, preferably 1.5 or more and 2.0 or less, and 1.5 or more and 1.7 or less. In the above range, the haze and the total light transmittance of the organic light emitting element encapsulation layer can be increased simultaneously, and the efficiency of extracting light having passed through the best light emitting layer having a refractive index of about 1.8 or more after emerging from the organic light emitting element can be increased. The binder may be contained singly or in combination of two or more species having different refractive indices and / or structures. When two or more kinds of binders are included, the refractive index of the binder may be determined by the sum of the weight ratios of the corresponding binders in the total binders multiplied by the refractive index of the corresponding binders, as described above.

The binder may include at least one high refractive index resin having a refractive index of 1.5 or more. Preferably, the high refractive index resin may include a resin having a refractive index of 1.5 to 2.0, 1.5 to 1.8, and 1.5 to 1.7. In the above range, WAD is improved, and both the haze of the sealing layer and the total light transmittance can be increased. The high refractive index resin is preferably a fluorene-based photopolymerizable resin, a biphenyl-based photocurable resin, a bisphenol-based photocurable resin, a thiophenyl-based photocurable resin, a thiobenzene-based photocurable resin, a phenylsulfide-based photocurable resin, a thionaphthalene- And a resin. Preferably, by including a fluorene-based photo-curing resin, it is possible to increase the extraction efficiency of light.

The fluorene-based photo-curable resin has a high refractive index compared to the polysilsesquioxane particles, so that the diffusion efficiency of light emitted from the polysilsesquioxane particles can be enhanced. The fluorene-based photo-curable resin may have a refractive index of 1.5 or more, specifically 1.5 or more and 1.8 or less and 1.5 or more and 1.7 or less. The fluorene-based photo-curable resin may include a resin having two or more functional groups, preferably two or more functional (meth) acrylates. Since the fluorene-based photo-curing resin exhibits a high refractive index due to the fluorene skeleton, it may contain only the fluorene skeleton. For example, the fluorene-based photo-curing resin may include a resin represented by the following formula (1)

≪ Formula 1 >

(Wherein m and n are each an integer of 1 or more, m + n is an integer of 2 to 8, R and R 'are each independently hydrogen or a methyl group, A and B are each independently a substituted or unsubstituted C1 To C5 alkylene group).

The fluorene-based photo-curing resin may be represented by the following formula (1-1)

≪ Formula 1-1 >

(Wherein m and n are each an integer of 1 or more, m + n is an integer of 2 to 8, R and R 'are each independently hydrogen or a methyl group, and R ¹ to R ⁸ are each independently hydrogen, A C1 to C10 alkoxy group, a C1 to C10 alkyl group, a C6 to C30 aryl group, a C7 to C30 arylalkyl group, or a C2 to C30 heteroaryl group)

Preferably, in Formula 1, m + n may be an integer of 2 to 6. The fluorene-based photo-curing resin may be synthesized by a conventional method known to those skilled in the art, or may be a commercially available product.

The biphenyl-based photo-curing resin may include a biphenyl-based photo-curable resin containing an alkylene oxide group.

The bisphenol-based photo-curing resin may include a bisphenol-based photo-curing resin having an alkylene oxide group as a bifunctional or higher functional polyfunctional resin,

(2)

(Wherein n and m are each an integer of 1 to 4, R and R 'are each independently hydrogen or a methyl group, C and D are each independently a substituted or unsubstituted C1 to C5 alkylene group, X is -C (R ⁹ ) (R ¹⁰ ) - wherein R ⁹ and R ¹⁰ are each independently hydrogen, a substituted or unsubstituted C1 to C5 alkyl group, or a substituted or unsubstituted C6 to C10 aryl group, or R ⁹ , R ¹⁰ are connected to each other to form a substituted or unsubstituted C 5 to C 20 ring), -SO ₂ -, -C = C (Cl ₂ ), a substituted or unsubstituted C6 to C20 arylene group, Or an unsubstituted C7 to C20 arylalkylene group).

Preferably, C, D are each independently a substituted or unsubstituted ethylene group, X is ^{-C (R 9) (R 10} ) - ( wherein, R ^9, R ¹⁰ independently represent a substituted or unsubstituted C1 respectively Lt; / RTI > to C5.

The binder may further include a photo-curable monomer containing the above-mentioned high refractive index photo-curable resin alone or a high refractive index photo-curable monomer. The photocurable monomer having a high refractive index dissolves a photocurable resin having a high refractive index and has an appropriate viscosity, so that the applicability of the composition for encapsulating an organic light emitting device can be enhanced.

The photocurable monomer having a high refractive index can be included in a composition for encapsulating an organic light emitting device when the photocurable resin having a high refractive index is solid or has a too high viscosity. The photocurable monomer having a high refractive index has a viscosity at 25 DEG C of 10 cps or more and 1000 cps or less, thereby lowering the viscosity of the composition and improving the applicability. The photo-curing monomer having a high refractive index is not particularly limited. However, by having a high refractive index, it is possible to prevent the refractive index canceling of the sealing layer formed of the photo-curing resin having a high refractive index and to prevent the decrease in the light extraction efficiency when used together with the polysilsesquioxane particle have. The photocurable monomer having a high refractive index has a lower refractive index than that of a photocurable resin having a high refractive index. Thus, when the amount of the photocurable monomer is excessive, the effect of improving light extraction and WAD may be reduced.

The photocurable monomer having a high refractive index may have a refractive index of 1.5 or more, preferably 1.5 or more and 2.0 or less and 1.5 or more and 1.7 or less. Within the above range, refractive index canceling of the sealing layer can be prevented. The photo-curable monomer of high refractive index may comprise mono- or bifunctional monomers. The photocurable monomer having a high refractive index may be a photocurable monomer containing an aromatic group, and examples thereof include a biphenyl-based photocurable monomer, a bisphenol-based photocurable monomer, a thiophenyl-based photocurable monomer, a thiobenzene-based photocurable monomer, a phenyl A sulfone-based photocurable monomer, a thionaphthalene-based photocurable monomer, and an alkyldiacrylate monomer. The photocurable monomer having a high refractive index may contain an aromatic group and an alkylene oxide group (e.g., an alkylene oxide group having 1 to 5 carbon atoms). In such a case, the effect of the present invention may be better. The biphenyl-based photocurable monomer is a monofunctional monomer, which can also increase the refractive index and lower the viscosity of the composition. The biphenyl-based photocurable monomer is a biphenyl-based photocurable monomer containing an alkylene oxide group.

In one embodiment, the binder may comprise a high refractive index photo-curable resin alone or may comprise a mixture of a high refractive index photo-curable resin and a high refractive index photo-curable monomer. The photocurable resin having a high refractive index may be in an amount of 30 wt% or more and less than 100 wt% based on the total amount of 100 wt% of the mixture. Further, it may be contained in an amount of 30 wt% or more and 90 wt% or less, and 30 wt% or more and 80 wt% or less. Within this range, it is possible to secure a coating property which is difficult to be realized by a photocurable resin alone with a high refractive index, without deteriorating the effect of light extraction and WAD improvement.

The binder may further contain at least one of a photocurable resin having a refractive index of less than 1.5, preferably a refractive index of not less than 0.1 and not more than 1.499, and a photocurable monomer. For example, such binders may include non-aromatic photopolymerizable resins without aromatic groups, non-aromatic photocurable monomers without aromatic groups. At least one of a photocurable resin having a low refractive index and a photocurable monomer may be contained in an amount of 0% by weight or more and 10% by weight or less in the entire binder. Within this range, the applicability of the composition can be improved without affecting the refractive index of the binder.

Initiators are those which cure the binder and may include conventional photocurable initiators known to those skilled in the art. For example, as the photopolymerization initiator, a phosphine oxide-based, benzoin-based, hydroxy ketone-based, aminoketone-based, or phosphine oxide-based photoinitiator can be used. Specific examples thereof include 2,4,6-trimethylbenzoyl (2,4,6-trimethylbenzoyl) -phenyl-phosphine oxide, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl Ether, benzoin isobutyl ether, 2,2-dimethoxy-2-phenylacetophenone, 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2- Acetophenone compounds such as p-toluenesulfonic acid, p-toluenesulfonic acid, p-toluenesulfonic acid, p-toluenesulfonic acid, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy- 1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 1-hydroxycyclohexyl phenyl ketone, (Methylthio) phenyl] -2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl- 2- , 4,4'-nonaicyldiaminobenzophenone, dichlorobenzophenone, 2-methyl anthraquinone, 2-ethyl anthraquinone, 2-t -butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal, acetophenone dimethylketal, p-dimethylaminobenzoic acid ester, oligo [2- Methyl-1- [4- (1-methylvinyl) phenyl] propanone]. In the present application, one kind or more kinds of the above can be used, but the present invention is not limited thereto. Preferably, the initiator is prepared by using a phosphine oxide initiator such as 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide or bis (2,4,6-trimethylbenzoyl) -phenyl-phosphine oxide, The OLED light emitting layer may be effectively cured with UV of a long wavelength region capable of curing the sealing layer without damaging the OLED light emitting layer.

The initiator may be contained in an amount of 0.1 part by weight to 10 parts by weight, preferably 1 part by weight or more and 10 parts by weight or less and 2 parts by weight or more and 7 parts by weight or less based on 100 parts by weight of the binder. Within this range, the highly viscous sealing composition can be sufficiently cured, and the light transmittance of the sealing layer can be prevented from being lowered due to the remaining amount of the initiator.

The sealing composition is a solvent-free sealing composition which is free of solvent and can completely prevent the outgassing from occurring compared with the conventional composition containing a solvent and can suppress deterioration of the performance of the device due to penetration of the organic solvent into the organic light- have.

The sealing composition may further contain conventional additives such as a heat stabilizer, a leveling agent, a deformer, and a pigment. The additive may be contained in the bag composition in an amount of 0 wt% or more and 1 wt% or less.

The sealing composition according to this embodiment can have a haze of 80% or more, preferably 80% or more and 99% or less at a wavelength of 400 nm to 700 nm after curing. The sealing composition according to this embodiment can have a total light transmittance of 80% or more, preferably 80% or more and 99% or less at a wavelength of 400 nm to 700 nm after curing. Within this range, it is possible to enhance extraction efficiency of light emission from the organic light emitting element.

The sealing composition according to this embodiment may have a refractive index after curing of 1.7 or less, preferably 1.3 or more and 1.7 or less, and 1.4 or more and 1.6 or less. Within this range, there may be an effect of improving the performance of the OLED. The sealing composition according to this embodiment has a water permeability (WVTR) of not less than 0.001 g / m ² day and not more than 10 g / m ² day, preferably not less than 0.001 g / m ² day and not more than 5 g / m ² ㆍ day. Within the above range, the performance improvement effect of the OLED can be obtained.

The sealing composition according to this embodiment may have a thickness of from 3 탆 to 30 탆, preferably from 5 탆 to 20 탆, and from 5 탆 to 15 탆 after curing. In the above range, it can be used for sealing an organic light emitting diode, and it can be applied to various cases by controlling the thickness of the sealing layer according to a gap.

The sealing composition according to this embodiment is a photocurable sealing layer, which is filled between a substrate including an organic light emitting element and a substrate and then cured, thereby being used for sealing an organic light emitting device.

The organic light emitting diode display of the present invention may include an encapsulation layer formed of the composition for encapsulating an organic light emitting diode of this embodiment.

1 is a cross-sectional view schematically showing an organic light emitting device according to an embodiment of the present invention. As shown in FIG. 1, the organic light emitting device 100 includes a first substrate 110; A second substrate 120 disposed to face the first substrate 110; An organic light emitting diode (D) formed on the first substrate (110); And an encapsulation layer 170 formed between the first substrate 110 and the second substrate 120 to cover the organic light emitting device D and the encapsulation layer 170 may be formed on the organic light emitting device D according to the embodiment of the present invention. And may be formed of a sealing composition.

The first substrate 110 may be a transparent substrate. In an embodiment, the first substrate may be a flexible substrate or a non-flexible substrate. For example, the first substrate may be a glass substrate or a plastic substrate. The material of the plastic substrate may be an insulating organic material, for example, a silicone resin, a polyamide resin, an epoxy resin, a polyethersulfone resin, a polyacrylate resin, a polyetherimide resin, a polyethylene naphthalate resin, a polyethylene terephthalate resin , Polyphenyl sulfide resin, polyarylate resin, polyimide resin, polycarbonate resin, cellulose resin, and the like.

The organic light emitting device D may be formed on the first substrate 110. The organic light emitting device D may include an organic light emitting device including an organic light emitting layer and a plurality of thin film transistors connected to the respective organic light emitting layers. And can be classified into a passive driving type and an active driving type depending on whether the driving of each organic light emitting element is controlled by a thin film transistor. The organic light emitting device of the present invention can be applied to both passive driving type and active driving type.

The second substrate 120 faces the first substrate 110 and may cover the organic light emitting device D in a contact or non-contact manner. The second substrate 120 may be formed of the same material as or different from the first substrate 110. In an embodiment, the second substrate 120 may be a glass substrate.

The organic light emitting device can be manufactured by a conventional method. For example, the sealing composition is coated on a release film and dried to produce an adhesive film. An adhesive film is laminated on the substrate in a single layer or a plurality of layers, and another substrate on which the organic light emitting element is formed is joined so that the adhesive film and the organic light emitting element are in contact with each other. Then, the organic light emitting device can be manufactured by thermosetting or photo-curing.

The organic light emitting device further includes a common element included in a conventional organic light emitting device, for example, a buffer layer for improving the smoothness of the first substrate and blocking the penetration of impurities, an organic film of an organic light emitting element, can do.

The organic light emitting device may further include a sealing film 150.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It should be understood, however, that the same is by way of illustration and example only and is not to be construed as in any way limiting its scope.

Specific specifications of the components used in the following examples and comparative examples are as follows.

(A) Binder:

(A1) Binder mixture: A mixture of fluorene type diacrylate resin (BPF-022 (enrichment property, refractive index: 1.60) and ethylene oxide group-containing biphenyl type monoacrylate (MIRAMER M1142 80 weight%: 20 weight% mixture.

(a1) CN996 (SATOMER, refractive index: 1.49) aliphatic urethane acrylate

(B) Light diffusion particles

(B1) SL-050M (Lotte Hi-tech): Polymethylsilsesquioxane particles, average particle diameter (D50): 0.5 占 퐉, refractive index: 1.42

(B2) SL-100M (Lotte high-tech material): polymethylsilsesquioxane particles, average particle diameter (D50): 1.0 占 퐉, refractive index: 1.42

(B3) SL-200M (Lotte high-tech material): polymethylsilsesquioxane particles, average particle diameter (D50): 2.0 占 퐉, refractive index: 1.42

(B4) SL-300M (Lotte high-tech material): polymethylsilsesquioxane particles, average particle diameter (D50): 3.0 占 퐉, refractive index: 1.42

(b1) SL-030M (Lotte high-tech material): polymethylsilsesquioxane particles, average particle diameter (D50): 0.3 占 퐉, refractive index: 1.42

(b2) SL-500M (Lotte high-tech material): polymethylsilsesquioxane particles, average particle diameter (D50): 5.0 占 퐉, refractive index: 1.42

(b3) TiONA ACTIV G5 (CRISTAL): Titania (TiO ₂ ) particles, particle diameter: 5 nm to 10 nm, refractive index: 2.6

(b4) EPRUI-R30 (EPRUI ): zirconia (ZrO ₂₎ particles, particle size: 20nm to 30nm, the refractive index: 2.1

(C) Initiator: BAPO

Example  One

10 parts by weight of the light diffusing particles B1 and 3 parts by weight of the initiator (C) were mixed with 100 parts by weight of the binder A1 and stirred to prepare an organic light emitting element encapsulating composition (viscosity at 25 캜: 6000 cps) .

Example  2 to Example  5

A composition for encapsulating an organic luminescent element was prepared in the same manner as in Example 1, except that the kind and content of the binder, the light diffusion particles, and the initiator were changed as shown in Table 1 (unit: parts by weight).

Comparative Example  1 to Comparative Example  3

A composition for encapsulating an organic luminescent element was prepared in the same manner as in Example 1, except that the kind and content of the binder resin, the light diffusion particles, and the initiator were changed as shown in Table 1 (unit: parts by weight).

Reference Example  1 and Reference Example  2

A composition for encapsulating an organic luminescent element was prepared in the same manner as in Example 1, except that the types of light-diffusing particles were changed to the following Table 1 (unit: parts by weight).

The properties of the composition for encapsulating an organic light emitting device prepared in Examples and Comparative Examples were evaluated in the following Table 1 and the results are shown in Table 1 below.

(1) and (2): haze and total light transmittance: A specimen having a thickness of 10 탆 obtained by coating the compositions of Examples and Comparative Examples according to ASTM D1003 by a screen printing method and UV curing was coated with NDH5000W Nippon Denshoku).

(3) Color change rate: A 10 탆 -thick piece obtained by coating the compositions of Examples and Comparative Examples by screen printing and UV curing was attached to an OLED panel. The OLED panel was measured at 0 ° from the front and 90 ° from the front with the measuring device EZcontrast (Eldim) at 1 ° intervals from 0 ° to 60 ° with respect to the front of the panel. The spectrum u'v '). The difference between the value at 0 ° and the value at intervals of 1 ° from 0 ° to 60 ° was calculated as the color change rate. A value of the intermediate color change rate ranging from 0 ° to 60 ° was taken as the max value of? U'v '. The lower the color change ratio, the higher the light extraction efficiency.

(4) WVTR (moisture permeability): Use a moisture permeability meter (PERMATRAN-W 3/33, MOCON). The photocurable composition was applied by screen printing on an Al sample holder and irradiated at 100 mW / cm < ² > for 10 seconds to UV cure to form a 5 [mu] m thick cured specimen. The film is allowed to stand for 24 hours at 37.8 ° C and 100% relative humidity using a moisture permeability meter (PERMATRAN-W 3/33, MOCON Co.) for a thickness of 5 μm, and then the moisture permeability is measured.

As shown in Table 1, the composition for encapsulating an organic luminescent element according to the present invention has high haze and total light transmittance, so that light extraction efficiency is high and the reliability of the organic light emitting device can be improved when encapsulating the organic luminescent element.

On the other hand, as shown in Table 1, Comparative Examples 1 to 3, in which the composition for encapsulating an organic light emitting diode according to this example was omitted, had a low haze and a relatively high color change ratio. This indicates that the WAD improvement effect is not superior to the embodiment.

Also, as shown in Table 1, in Comparative Example 1 and Reference Example 2 containing titania and zirconia in place of the polymethylsilsesquioxane particle, haze and total light transmittance were all low and the color change ratio was relatively high. This means that the WAD improvement effect is not superior to the embodiment.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (14)

A binder, a polysilsesquioxane particle and an initiator,
Wherein the polysilsesquioxane particles have an average particle diameter (D50) of 0.5 mu m or more and 3.0 mu m or less,
Wherein the difference between the refractive index of the binder and the refractive index of the polysilsesquioxane particle is 0.08 or more and 0.20 or less.
The composition for encapsulating an organic luminescent element according to claim 1, wherein the polysilsesquioxane particles comprise polymethylsilsesquioxane particles.
The composition for encapsulating an organic luminescent element according to claim 1, wherein the polysilsesquioxane particle has a refractive index of 1.0 or more and less than 1.5.
The composition for encapsulating an organic light emitting device according to claim 1, wherein the polysilsesquioxane particle is contained in an amount of 1 part by weight to 30 parts by weight with respect to 100 parts by weight of the binder.
The optical information recording medium according to claim 1, wherein the binder is selected from the group consisting of a fluorene-based photopolymerizable resin, a biphenyl-based photopolymerizable resin, a bisphenol-based photopolymerizable resin, a thiophenyl-based photopolymerizable resin, a thiobenzyl- A thiophene-based photo-curing resin, and a thiophene-based photo-curable resin.
6. The composition for encapsulating an organic luminescent element according to claim 5, wherein the binder comprises a fluorene-based photo-curing resin.
[7] The method of claim 5, wherein the binder is selected from the group consisting of a biphenyl-based photocurable monomer, a bisphenol-based photocurable monomer, a thiophenyl-based photocurable monomer, a thiobenzene-based photocurable monomer, a phenylsulfide-based photocurable monomer, a thionaphthalene- An alkyl diacrylate monomer, and a high refractive index photo-curable monomer comprising at least one of an alkyl diacrylate monomer and an alkyl diacrylate monomer.
8. The composition according to claim 7, wherein the high refractive index photo-curing monomer contains an alkylene oxide group.
8. The composition for encapsulating an organic luminescent element according to claim 7, wherein the binder comprises 30 wt% or more and less than 100 wt% of the high refractive index photo-curing resin in the mixture of the high refractive index photo-curing resin and the high refractive index photo- .
The composition for encapsulating an organic luminescent element according to claim 1, wherein the initiator comprises a phosphine oxide-based photoinitiator.
The composition for encapsulating an organic luminescent element according to claim 1, wherein the composition for encapsulating an organic luminescent element is a solventless type.
The composition for encapsulating an organic light emitting diode according to claim 1, wherein the composition for encapsulating an organic luminescent element has a haze of 80% or more and a total light transmittance of 80% or more at a wavelength of 400 nm to 700 nm after curing.
An organic light emitting device encapsulation layer formed from the composition for encapsulating an organic luminescence element according to any one of claims 1 to 12.
An organic light emitting diode display device comprising an organic light emitting device encapsulation layer formed of the composition for encapsulating an organic light emitting diode according to any one of claims 1 to 12.

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