KR101922300B1 - 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

Wherein the polysilsesquioxane particles are contained in an amount of 1 part by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the binder, and wherein the binder contains polysilsesquioxane particles and an initiator, , An organic light emitting device encapsulation layer formed therefrom, and an organic light emitting diode display device including the same.

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 light emitting diode according to the present invention comprises a binder, polysilsesquioxane particles and an initiator, wherein the binder contains a fluorene-based photo-curable monomer, and the polysilsesquioxane particles comprise 100 parts by weight of the binder 1 part by weight or more and 30 parts by weight 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) acrylic 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, C30 aryl group, C7-C30 arylalkyl group, cyano group, C2-C10 carbonyl group or C2-C30 heteroaryl group.

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 luminescent element according to this embodiment includes a binder, polysilsesquioxane particles and an initiator, and the binder may include a fluorene-based photo-curable monomer.

The composition for encapsulating an organic light emitting diode according to the present embodiment improves WAD by diffusing light emitted from an organic light emitting device including the best light emitting layer having a refractive index of about 1.8 or more through the polysilsesquioxane particles and includes a fluorene photo- High-refractive-index monomers can be used to increase the light extraction efficiency. 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 this embodiment uses polysilsesquioxane particles having a refractive index lower than that of zirconia and titania, but the polysilsesquioxane particles are used together with a fluorene-based photo-curing monomer having a high refractive index, When the haze and total light transmittance are increased simultaneously, it is possible to improve the WAD of the organic light emitting device by suppressing the total reflection of light in the particle by inducing irregular reflection instead of total reflection at the interface between the organic light emitting device and the sealing layer. Can be significantly increased. Further, the present invention is based on the fact that the polysilsesquioxane particle and the fluorene-based photo-curable monomer are contained together to suppress the moisture and oxygen penetration in the encapsulation of the organic light emitting device, thereby improving the reliability of the organic light emitting device.

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 fluorene-based photo-curing monomer can be easily controlled. The fluorene-based photocurable monomer has a higher refractive index than that of the polysilsesquioxane particles, so that the diffusion efficiency of light emitted from the polysilsesquioxane particles can be enhanced. The refractive index difference between the fluorene-based photocurable monomer and the polysilsesquioxane particle may be 0.5 or less, preferably from 0 to 0.5 or less, or from 0.05 to 0.5, and may be 0.05 or more to 0.3 or less. Within this range, it is possible to easily control the refractive index between the monomer and the particles, to improve the WAD, to increase the light extraction efficiency, and to increase both the haze of the sealing layer and the total light transmittance. The fluorene-based photocurable monomer 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. In the above range, WAD is improved, and both the haze of the sealing layer and the total light transmittance can be increased.

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 And most preferably 10 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 polysilsesquioxane particles may be contained in an amount of 10 parts by weight or more and 50 parts by weight or less, preferably 15 parts by weight or more and 45 parts by weight or less, based on 100 parts by weight of the fluorene-based photocurable monomer. 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.

Hereinafter, the binder, the polysilsesquioxane particle and the initiator of this embodiment will be described in more detail.

The binder may be cured by an initiator to form the organic light emitting element encapsulation layer. The binder may further include a fluorene-based photocurable monomer alone or a high refractive index non-fluorene-based photocurable monomer described below. The non-fluorene-based photo-curing monomer having a high refractive index does not contain a fluorene skeleton but dissolves the fluorene-based photo-curable monomer and has an appropriate viscosity, so that the applicability of the composition for encapsulating an organic light emitting element can be enhanced.

The fluorene-based photocurable monomer may include (difunctional) or more (preferably) bifunctional to hexafunctional (meth) acrylates. Since the fluorene-based photocurable monomer exhibits a high refractive index due to the fluorene skeleton, it may contain only the fluorene skeleton. For example, the fluorene-based photo-curable monomer may comprise a monomer of the following formula:

≪ 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 photocurable monomer may be represented by the following general 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 photocurable monomer may be synthesized by a conventional method known to those skilled in the art, or may be a commercially available product.

The non-fluorene photo-curing monomer having a high refractive index can be included in the composition for encapsulating an organic light-emitting device when the fluorene-based photo-curing monomer is solid or has a too high viscosity. The non-fluorene-based photo-curing monomer having a high refractive index has a viscosity of 10 cps or more and 1000 cps or less at 25 캜, thereby lowering the viscosity of the composition and improving the applicability. The high refractive index non-fluorene photo-curable monomer is not particularly limited, but it has a high refractive index to prevent refractive index cancellation of the encapsulating layer formed of the fluorene-based photo-curable monomer, and when used with the polysilsesquioxane particle, The efficiency reduction can be prevented. The high refractive index non-fluorene photo-curing monomer may have a lower refractive index than the fluorene-based photo-curable monomer, so that the effect of light extraction and WAD improvement may be reduced when the refractive index is excessively contained. The refractive index of the non-fluorene-based photocurable monomer having a high refractive index 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. Non-fluorene photo-curable monomers having a high refractive index may include mono- or bifunctional monomers.

The non-fluorene photo-curable monomer having a high refractive index 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 methacrylate monomer, an alkyl methacrylate monomer, and an alkyl diacrylate monomer.

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.

The bisphenol-based photo-curing monomer may be a bifunctional photo-curable monomer having an alkylene oxide group as a bifunctional or higher-functional monomer and may include the following formula 2:

(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 To C5 alkyl group).

The binder may comprise a fluorene-based photocurable monomer alone or a mixture of a fluorene-based photocurable monomer and a high-refractive-index non-fluorene photocurable monomer. The fluorene-based photocurable monomer may be 30% by weight or more based on 100% by weight of the total amount of the mixture. In addition, it may be contained in an amount of 30 wt% or more and 90 wt% or less, 30 wt% or more and 80 wt% or less, preferably 30 wt% or more and 70 wt% or less and 30 wt% or more and 60 wt% or less. Within the above range, the fluorine-containing photo-curing monomer alone can provide a coatability that is difficult to realize without deteriorating the effect of light extraction and WAD improvement.

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 polysilsesquioxane particle has a low refractive index compared to the binder, it may include a polyalkylsilsesquioxane particle in which an alkyl group having 1 to 5 carbon atoms such as a methyl group is connected to silicon. For example, the polysilsesquioxane particles may comprise polymethylsilsesquioxane (PMSQ) particles. The polymethylsilsesquioxane particles have a lower refractive index than the fluorene-based photo-curing monomer and can increase the light diffusion efficiency.

The polysilsesquioxane particles are optically transparent particles having an average particle diameter (D50) of 0.1 占 퐉 or more and 10 占 퐉 or less. In the above range, it may be included in the organic light emitting element encapsulation layer. Preferably, the polysilsesquioxane particles may have an average particle diameter of 0.5 占 퐉 or more and 5 占 퐉 or less, 0.5 占 퐉 or more and 3 占 퐉 or less, and 0.5 占 퐉 or more and 2 占 퐉 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. Particularly, since the polysilsesquioxane particles have an average particle size of 0.5 mu m or more, the average particle diameter of zirconia and titania is relatively large, thereby suppressing the total internal reflection of light emitted from the organic light emitting element and increasing the light extraction efficiency. The polysilsesquioxane particles may be prepared by conventional methods or may include commodities sold commercially.

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 according to the present embodiment is a composition for sealing a solvent-free, solvent-free composition, which can completely block the generation of outgassing compared with a conventional composition containing a solvent, and deteriorates the performance of the device due to penetration of the organic solvent Can be suppressed.

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 3 탆 to 30 탆, preferably 5 탆 -20 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 in any way as limiting the invention.

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

(A) Binder

(A1) Binder: 60 wt% of a fluorene-based diacrylate monomer (refractive index: 1.606, BPF-022 (enrichment property)) and biphenyl monoacrylate (refractive index: 1.576, M1142 By weight.

(A2) M1142 (Amino Specialty): biphenyl-based ethylene oxide group-containing monoacrylate (refractive index: 1.576)

(A3) BP-032 (concentrating agent): diacrylate containing bisphenol-based ethylene oxide group (refractive index: 1.5468)

(A4) EPM-342 (enrichment solvent): ethoxylated propylated dimethacrylate (non-fluorene-based, refractive index: 1.4572)

(B) Light diffusion particles

(B1) SL100 (Lotte high-tech material): polymethylsilsesquioxane particles, particle diameter: 1 占 퐉, refractive index: 1.4

(B2) TiONA ACTIV G5 (CRISTAL): Titania (TiO ₂ ) particles, particle diameter: 5 nm to 10 nm, refractive index: 2.6

(B3) EPRUI-R30 (EPRUI ): zirconia (ZrO ₂₎ particles, particle size: 20nm to 30nm, the refractive index: 2.1

(C) Initiator: BAPO

Example  One

20 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 a composition for sealing an organic luminescent element (viscosity at 25 캜: 19000 cps) .

Example  2 to Example  7

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  7

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, light-diffusing particles, and initiator were changed as shown in Table 2 (unit: parts by weight).

The properties of the compositions for encapsulating organic light emitting devices prepared in Examples and Comparative Examples were evaluated in the following Tables 1 and 2, and the results are shown in Tables 1 and 2 below.

(1) and (2) Haze and total light transmittance: A specimen having a thickness of 10 占 퐉 obtained by coating the compositions of Examples and Comparative Examples according to ASTM D1003 by a screen printing method and UV curing was evaluated in accordance with ASTM D1003 using NDH5000W 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 a * b *). 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 having a high intermediate color change rate from 0 DEG to 60 DEG was taken as a max value of DELTA a * b *. 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 moisture permeability is measured for 24 hours at 37.8 ° C and 100% relative humidity using a moisture permeability meter (PERMATRAN-W 3/33, MOCON) for a film thickness of 5 μm.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 bookbinder (A1) 100 100 80 80 80 50 50 (A2) - - 20 20 - - 50 (A3) - - - - 20 50 - (A4) - - - - - - - Light diffusion particle (B1) 20 10 20 10 10 10 10 (B2) - - - - - - - (B3) - - - - - - - Initiator (C) 3 3 3 3 3 3 3 Haze (%) 97 92.6 93.8 84.9 84.1 80.1 82.7 Total light transmittance (%) 88.5 91.6 83.2 91.4 94.1 95.3 93.2 Color change rate
(max DELTA a * b * @ 0 DEG to 60 DEG) 0.007 0.008 0.006 0.008 0.008 0.007 0.009 WVTR
(g / m ² ㆍ day) 3.1 3.0 2.9 3.2 2.7 2.8 3.2

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 bookbinder (A1) - - - - - - - (A2) 100 100 - - - 100 100 (A3) - - - - - - - (A4) - - 100 100 100 - - Light diffusion particle (B1) - - 10 9 9 5 5 (B2) 5 - - One - 5 - (B3) - 5 - - One - 5 Initiator (C) 3 3 3 3 3 3 3 Haze (%) 69.4 56.2 59.2 87.5 84.3 73.4 72.1 Total light transmittance (%) 51.9 64.2 90.7 73.2 77.6 67.1 69.2 Color change rate
(max DELTA a * b * @ 0 DEG to 60 DEG) 0.029 0.031 0.026 0.019 0.021 0.025 0.026 WVTR
(g / m ² ㆍ day) 2.8 3.5 3.2 2.9 3.3 2.8 2.9

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 2, Comparative Examples 1 to 7 in which the composition for encapsulating an organic light emitting diode according to the present invention deviates from the composition for encapsulating an organic light emitting device have both lower haze and total light transmittance and higher color change rates.

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 binder comprises a fluorene-based photocurable monomer,
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,
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.
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 particles have an average particle diameter (D50) of 0.1 占 퐉 or more and 10 占 퐉 or less.
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 fluorine-based photocurable monomer according to claim 1, wherein the fluorene-based photocurable monomer has a refractive index higher than that of the polysilsesquioxane particle, and the refractive index difference between the fluorene-based photocurable monomer and the polysilsesquioxane particle is 0 to 0.5, (EN) Composition for encapsulating an organic luminescent element.
The composition for encapsulating an organic luminescent element according to claim 1, wherein the binder further comprises a non-fluorene photo-curable monomer.
The non-fluorene photocurable monomer according to claim 6, wherein the non-fluorene photocurable monomer 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 thionaphthalene-based photo-curable monomer, and an alkyldiacrylate monomer.
The composition according to claim 6, wherein the non-fluorene photo-curable monomer contains an alkylene oxide group.
7. The organic electroluminescent device according to claim 6, wherein the binder comprises at least 30% by weight of the fluorene-based photocurable monomer in the mixture of the fluorene-based photocurable monomer and the non-fluorene-based photocurable monomer Composition.
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.
delete 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 11.
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 11.

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