KR20120078291A - Moisture absorbent filler for organic electroluminescence device, method for preparing thereof and organic electroluminescence containing the same - Google Patents

Abstract

PURPOSE: A moisture absorbent filler for an organic light emitting device, a manufacturing method thereof, and the organic light emitting device including the same are provided to prevent a dark spot by using calcium as a moisture absorbent layer. CONSTITUTION: A moisture absorbent filler for an organic light emitting device includes a moisture absorbent layer(40) and a filler layer(30). The moisture absorbent layer is formed on an encapsulation material(50). The filler layer is formed on the moisture absorbent layer. A storage modulus measured by DMA(Dynamic Mechanical Analysis) is 0.1-100MPa in the filler layer. Glass transition temperature is -50 to 80°C to in the filler layer.

Description

Moisture Absorbent Filler for Organic Electroluminescence Device, Method for Preparing Sweet and Organic Electroluminescence Containing the same}

The present invention relates to a moisture absorbing filler for an organic light emitting device, a method for manufacturing the same, and an organic light emitting device including the same. More specifically, the present invention applies a filler layer having a specific moisture absorption layer and specific physical properties, so that the warpage is less affected by moisture absorption, dark spots are not generated, and the defect of the device can be greatly reduced, and the organic light emission can realize light and short reduction. Hygroscopic filler for the device, and an organic light emitting device comprising the same.

The organic light emitting device (hereinafter, referred to as OLED) has a structure in which an organic EL layer, which is a thin film containing a fluorescent organic compound, is sandwiched between an anode and a cathode constituting a pair of electrodes, and excitons are formed by injecting holes and electrons into the thin film. It is a self-luminous device which produces an exiton and uses the emission of light (fluorescence and phosphorescence) when this exciton is inactivated.

When the organic light emitting diode is driven for a certain period of time, the organic film and the metal film, which are components of the organic light emitting diode, are gradually oxidized due to the penetration of moisture or generation of oxygen, carbon monoxide, moisture, and the like. There is a problem that the light emission characteristics are significantly degraded. In other words, the light emitting material reacts with moisture to be converted into non-advertised molecules to form dark spots, thereby lowering the luminous efficiency, and also lowering the charge transport ability, thereby increasing the impedance of the device. Due to the phenomenon that peeling from the organic taste occurs, the electron injection efficiency is drastically reduced and the life is gradually reduced.

As such, since the organic light emitting device is vulnerable to moisture and oxygen, a method of mounting a getter including a drying means capable of absorbing moisture during an encapsulation process to block moisture and oxygen is used in the device.

As the drying means, a hygroscopic powder such as calcium oxide (CaO) is placed in a water-permeable bag and sealed, or the pellet is compressed or the powder is mixed with a polymer binder to form a film. How to do it.

The method of using the filler in a moisture-permeable bag has a disadvantage that the thickness thereof is thicker than that of the film form, and the bag swelling phenomenon at high temperature and the filler powder fall off and fall onto the device. It is difficult and has a disadvantage of poor durability.

Recently, a getter is manufactured in a film form by mixing an inorganic filler and a polymer binder. However, in the case of the hygroscopic material prepared by mixing a metal oxide powder such as CaO with a polymer binder, the surface roughness may grow due to the volume expansion of CaO during moisture absorption or may be bent due to volume expansion. This may cause problems such as dark spots and scratches by damaging the electrodes in the device in direct contact with the device.

The present inventors apply a specific moisture absorption layer and a filler layer having specific physical properties in order to improve such a problem, the warpage is less affected by moisture absorption, dark spots are not generated, and defects of the device can be greatly reduced, and light and small size can be realized. The development of a hygroscopic filler for an organic light emitting device.

An object of the present invention is to provide a moisture absorbing filler for an organic light emitting device excellent in the moisture absorption efficiency without the occurrence of dark spots and a method of manufacturing the same.

Another object of the present invention is to provide a moisture absorbing filler for an organic light emitting device and a method of manufacturing the same, which can prevent a moisture absorbing layer containing a moisture absorbent from directly contacting the device and simultaneously satisfy the role of a filler between the device and the encapsulation substrate. will be.

Still another object of the present invention is to provide a moisture absorbing filler for an organic light emitting device and a method of manufacturing the same, in which surface roughness growth and volume expansion do not occur due to volume expansion of the moisture absorbent.

Still another object of the present invention is to provide a moisture absorbing filler for an organic light emitting device and a method of manufacturing the same, which can minimize the thickness of the moisture absorbing filler.

Still another object of the present invention is to provide an organic light emitting device having improved light emission characteristics and lifespan by effectively preventing deterioration of constituent thin films of the device by applying the hygroscopic filler for the organic light emitting diode.

Technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

One aspect of the present invention relates to a hygroscopic filler for an organic light emitting device. The moisture absorption filler for the organic light emitting device is a moisture absorption layer formed on the encapsulation substrate; And a filler layer formed on the moisture absorbing layer. The hygroscopic layer is calcium, and the filler layer is characterized in that the storage modulus measured by DMA (Dynamic Mechanical Analysis) method is 0.1 ~ 100MPa.

In embodiments, the filler layer is characterized in that the water absorption of 0 to 10 wt% by the following formula:

 Preferably the water absorption may be 0 ~ 5wt%.

In one embodiment, the filler layer may be formed continuously.

In another embodiment, the filler layer may be formed discontinuously. In embodiments, the filler layer may be patterned.

The filler layer may have an adhesive force of 100 gf / cm or more and an adhesive force of 10 gf / mm or more.

In embodiments, the filler layer may be porous.

In an embodiment, the filler layer may be a cured product of a polymer resin having a glass transition temperature of -50 to 80 ° C.

In an embodiment, the polymer resin may be a vinyl acetate resin (PVAc) resin, polyvinyl pyrrolidone (PVP) resin, polyester resin, polyolefin resin, (meth) acrylate resin, polycarbonate resin, acrylic Ronitrile resin, cellulose acetate, epoxy resin, phenoxy resin, siloxane resin, sulfone resin, polyamide resin, polyurethane resin, polyvinyl resin, urethane acrylate resin, florin resin, rubber furnace It may comprise one or more from the group consisting of.

The polymer resin may contain a hydrophilic group.

In one embodiment, the thickness ratio of the moisture absorbing layer and the filler layer may be 1: 2 to 50.

The encapsulation substrate is formed to face the organic light emitting device, and may be metal or glass.

Another aspect of the present invention relates to a method of manufacturing a hygroscopic filler for an organic light emitting device. The method comprises depositing a calcium hygroscopic layer on one surface of the encapsulation substrate; And forming a filler layer on the calcium hygroscopic layer.

In an embodiment, the filler layer may be formed by coating or laminating on the calcium hygroscopic layer.

Another aspect of the invention relates to an organic light emitting device comprising the hygroscopic filler for the organic light emitting device.

In an embodiment, the organic light emitting diode includes a substrate; An organic light emitting unit formed on one surface of the substrate and including a first electrode, an organic light emitting layer, and a second electrode; An encapsulation substrate formed to face the organic electroluminescent unit at intervals so as to protect the organic electroluminescent unit; And drying means disposed between the encapsulation substrate and the organic electroluminescent portion, wherein the drying means is the hygroscopic filler.

In one embodiment, the hygroscopic filler is not in contact with the organic light emitting unit.

In another embodiment, the filler layer of the hygroscopic filler may be in contact with the organic light emitting unit.

The present invention is excellent in hygroscopic efficiency without the occurrence of dark spots, it is possible to prevent the absorbent layer containing the absorbent from directly contacting the device and to satisfy the role of filler between the device and the encapsulation substrate at the same time, the volume expansion of the absorbent The present invention provides a moisture absorbing filler for an organic light emitting device capable of minimizing the thickness of the moisture absorbing filler without surface roughness growth and volume expansion. In addition, by applying the moisture-absorbing filler for the organic light emitting device has an effect of providing an organic light emitting device with improved light emission characteristics and lifespan by effectively preventing degradation of the constituent thin film of the device.

1 (a) to (b) is a cross-sectional view of the hygroscopic filler for the organic light emitting device of the present invention formed on the encapsulation substrate.
2 (a) to 2 (b) are schematic cross-sectional views of an organic EL device to which the moisture absorbing filler for an organic light emitting device of the present invention is applied.

For organic light emitting device Hygroscopic filler

1 (a) to (b) is a cross-sectional view of the hygroscopic filler for the organic light emitting device of the present invention formed on the encapsulation substrate. As shown, in the moisture absorbing filler for the organic light emitting device of the present invention, the moisture absorption layer 40 is formed on the encapsulation substrate 50, and the filler layer 30 is formed on the moisture absorption layer 40. have.

Conventionally, organic-inorganic composite materials including metal oxides such as CaO have been mainly used as the moisture absorption layer. However, hygroscopic fillers containing metal oxides such as CaO tend to expand in volume when moisture is absorbed, resulting in surface roughness growth, warpage, and damage to electrodes in the device, which can cause problems such as dark spots and scratches. .

In the present invention, calcium (Ca) is used as the moisture absorption layer 40 without using a metal oxide such as CaO.

The moisture absorption layer 40 may be formed by a method such as CVD, sputtering, evaporation. It is preferable to form by double deposition. The deposition may be applied to both physical or chemical deposition.

In the embodiment, the thickness of the moisture absorbing layer 40 is preferably 5 μm or less, preferably 2 μm or less, in consideration of the deposition rate and the surface roughness. In embodiments it may be formed from 0.1 to 2 ㎛, preferably 0.5 to 1.5 ㎛. The hygroscopicity is excellent in the above range and the warpage effect is small.

The filler layer is formed between the moisture absorbing layer and the device to prevent contact between the moisture absorbing layer and the device, absorbs some moisture from the device and transfers the remaining water to the moisture absorbing layer, and at the same time fulfills the role of the filler between the device and the cover. Use materials that are present. Preferably, the remaining monomers and other foreign materials are selected and used.

In one embodiment, the filler layer has a storage modulus of 0.1 to 100 MPa, preferably 1 to 100 MPa, as measured by DMA (Dynamic Mechanical Analysis). It is possible to secure the dimensional stability in the above range, sufficient wetting property when applying the filler layer, and it is possible to secure excellent film properties because no scratch occurs. More preferably, it is 3-85 MPa.

In addition, the filler layer has a water absorption of 0 to 10wt%, and preferably 0.1 to 5wt%, measured by a weight comparison method before and after moisture absorption. It has excellent moisture absorption efficiency in the above range. The weight comparison method before and after the absorption can be obtained by the following equation.

In the present invention, the filler layer 30 has both moisture absorption and filler functions, and moisture from the device is primarily absorbed by the filler layer 30, and the non-absorbed moisture is secondarily absorbed into the moisture absorbing layer 40. do.

In one embodiment, the filler layer may be formed continuously, and in other embodiments, the filler layer may be formed discontinuously. FIG. 1A illustrates that the filler layer 30 is continuously formed on the moisture absorbing layer 40, and FIG. 1B illustrates that the filler layer 30 is discontinuously formed on the moisture absorbing layer 40. It is shown. In one embodiment, when the filler layer 30 is discontinuously formed on the moisture absorbing layer 40, the filler layer may be patterned. The form of the said pattern is not specifically limited. In embodiments, the pattern may be a dot pattern, a ring pattern, a stripe pattern, a grid pattern, a wavy pattern, a zigzag pattern, a honeycomb pattern, or the like, but is not limited thereto. In addition, the patterns may have a combined pattern. When the filler layer 30 is discontinuously formed on the moisture absorbing layer 40, the area of the filler layer 30 is at least 30% or more, preferably 50 to 100% of the area of the moisture absorbing layer 40. .

The filler layer 30 may have an adhesive force of 100 gf / cm or more, preferably 200 to 1000 gf / cm. In the above range, the filler layer 30 is easily laminated with the Ca moisture absorbing layer 40. The adhesive strength is measured by peel strength (90 degree peel, width 1cm) by Instron (Universal test machine). In addition, the filler layer 30 may have an adhesive force of 10 gf / mm or more, preferably 50 to 1000 gf / mm. It is easy to fix the encapsulation substrate and the device when contacting the device after lamination in the above range. The adhesive force is measured by a tackness tester (diameter: 5 mm) method.

In one embodiment, the filler layer may be porous. Preferably it has a porosity of 0.1 to 5%. It has a fast moisture absorption rate in the above range. By applying the porous filler layer in this way, moisture from the device is transferred to the moisture absorption layer 40 through the pores.

The filler layer may be made of a polymer resin having a glass transition temperature of -50 to 80 ℃. It can have excellent adhesion and adhesion in the above range.

In an embodiment, the polymer resin may be a vinyl acetate resin (PVAc) resin, polyvinyl pyrrolidone (PVP) resin, polyester resin, polyolefin resin, (meth) acrylate resin, polycarbonate resin, acrylic Ronitrile resin, cellulose acetate, epoxy resin, phenoxy resin, siloxane resin, sulfone resin, polyamide resin, polyurethane resin, polyvinyl resin, urethane acrylate resin, florin resin, rubber It may comprise one or more from the group consisting of. Preferably, they are (meth) acrylate resin, epoxy resin, polyurethane resin, siloxane resin, and rubber. These can be applied individually or in mixture of 2 or more types.

The polymer resin may contain a hydrophilic group.

In one embodiment, the rubber and the epoxy resin may be mixed and used, and the mixing ratio may be 50:50 to 90:10. In the above range, it is possible to include a packed layer having a high storage modulus and to be able to absorb shock. As the rubber component, a rubber containing a hydrophilic group can be preferably used.

The polymer resin used in the filler layer may have a weight average molecular weight of 100,000 to 1,000,000 g / mol. The coating film properties of the filler layer in the above range is improved, there is an advantage in that it is easy to transfer moisture from the moisture absorbing layer.

The filler layer may be formed by a method such as coating, coating, lamination, and the like. In one embodiment, the polymer resin may be dissolved in a solvent and then coated on a release film by a casting method, and then the filler layer formed by heat treatment may be laminated on the moisture absorbing layer. In another embodiment, the polymer resin may be dissolved in a solvent and then directly applied or coated on a moisture absorbing layer.

The filler layer has a thickness of 100 µm or less, preferably 50 µm or less, and more preferably 5 to 30 µm. It is possible to realize excellent hygroscopicity and light weight reduction in the above range.

In one embodiment the thickness ratio of the moisture absorbing layer and the filler layer may be 1: 1.1 to 50. When the moisture absorption of the moisture absorption layer in the above range can prevent device defects due to the growth of the surface roughness, there is an advantage that the filler layer is easy to transfer moisture and oxygen.

For organic light emitting device Hygroscopic filler  Manufacturing method

Another aspect of the present invention relates to a method of manufacturing a hygroscopic filler for an organic light emitting device. The method comprises depositing a calcium hygroscopic layer on one surface of the encapsulation substrate; And forming a filler layer on the calcium hygroscopic layer.

The encapsulation substrate is formed to face the organic light emitting device, and may be metal or glass. In an embodiment, inorganic / metal materials such as metal foil may be used in addition to glass cavity and flat glass.

The calcium absorption layer may be formed by a method such as CVD, sputtering, evaporation. It is preferable to form by double deposition. The deposition may be applied to both physical or chemical deposition. In one embodiment, the deposition conditions may be performed at 5 ~ 30torr 1 ~ 10 ~ / sec.

The filler layer may be formed by directly applying or laminating on the calcium hygroscopic layer. In a specific embodiment, after dissolving the polymer resin constituting the filler layer in a solvent and then applied to the release film by a casting method, the filler layer formed by heat treatment may be laminated on the moisture absorption layer. In another embodiment, the polymer resin may be dissolved in a solvent and then directly applied or coated on a moisture absorbing layer.

The solvent may be preferably an organic solvent capable of dissolving the polymer resin. In embodiments, ketones, acetates, and the like may be used, but are not necessarily limited thereto.

The mixing ratio of the polymer resin and the solvent is adjusted to 30 to 80% by weight solid content. It is easy to apply in the above range, there is an advantage that can lower the uniform film thickness control and surface roughness.

In addition, the curing agent may be further included in the mixture of the polymer resin and the solvent, and may be further included in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the polymer resin.

The applied filler layer may be dried through a drying or heat treatment process and then cured. The drying may be carried out at 50 ~ 150 ℃, preferably 80 ~ 130 ℃ temperature conditions.

Organic light emitting device

Another aspect of the invention relates to an organic light emitting device comprising the hygroscopic filler for the organic light emitting device. 2 (a) to 2 (b) are schematic cross-sectional views of an organic light emitting device according to an embodiment of the present invention. FIG. 2A illustrates a case where the encapsulation substrate is a flat glass 51 and FIG. 2B illustrates a case where the encapsulation substrate is a cavity glass 52. In the present invention, there is no particular limitation on the material or form of the encapsulation substrate. Flat glass may be preferably applied to minimize defects due to thermal expansion coefficient aberration and to reduce thickness.

The organic light emitting device is a substrate (10); An organic light emitting unit 20 formed on one surface of the substrate and including a first electrode, an organic light emitting layer, and a second electrode; An encapsulation substrate (51, 52) formed to face the organic light emitting portion at intervals so as to protect the organic light emitting portion; And drying means disposed between the encapsulation substrate and the organic light emitting unit, and the drying means may use the hygroscopic filler 100 for the organic light emitting device of the present invention.

In one embodiment, the hygroscopic filler 100 is not in contact with the organic light emitting unit 20. That is, the filler layer 30 may be formed to be spaced apart from the organic light emitting unit 20.

In another embodiment, the filler layer 30 of the hygroscopic filler may be in contact with the organic light emitting unit 20. However, even in this case, the moisture absorbing layer 30 does not contact the organic light emitting unit 20.

The encapsulation substrate may be sealed with the substrate 10 by a sealing material 52. The sealing material 52 is well known by those of ordinary skill in the art.

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

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

Example  One

Ca was deposited at 4 μs / sec. At 0-7 torr using Flat Evaporation. The final deposition thickness was 1 μm and the deposition area was 15 cm × 15 cm to form a Ca deposition layer. To form the filler layer, Acryl Binder (BA / AN / GMA copolymer) was dissolved in ketone, adjusted to solid content of 30wt%, and applied to the release film by casting. After drying at 130 ℃ / 24hr. To remove residual moisture and organic foreign matter to form a filler layer of 20μm thickness. The filler layer was laminated with the filler layer on the Ca deposition layer through a lamination process, and the final structure was a structure in which Flat Glass / Ca / fill layer / release film was sequentially stacked.

An encapsulation substrate having a hygroscopic filler fixed therein is disposed on a glass substrate on which an organic light emitting part including a first electrode, an organic light emitting layer, and a second electrode is accommodated to seal an organic light emitting device. Prepared.

Example  2-3 and Comparative example  1-3

It carried out similarly to Example 1 except having changed the material of the Ca deposition layer and the layered material layer by the method of Table 1 below. Example 3 is a filler layer except that a mixture of 3 parts by weight of an Amine curing agent is applied to 100 parts by weight of a polymer resin having a content ratio of Rubber (Emerald performance Materials, CTBN) / Epoxy (Kukdo Chemical, YD128) of 7: 3. Is performed in the same manner as in Example 1.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Ca
Deposition Layer Thickness (μm) One 3 5 0 5 - CaO Mixing ratio (wt%) - - - - - 30wt% Packed bed Kinds Acryl Acryl Rubber + Epoxy Acryl - Acryl Thickness (μm) 20 20 20 20 - 20 Storage modulus 50 MPa 5 MPa 80 MPa 50 MPa - 10 MPa Tg -10 ° C -32 ℃ -20 ° C -10 ° C - -10 ° C Adhesive force (gf / cm) 550 210 980 550 0 85 Adhesive force (gf / mm) 80 118 52 80 0 48

* Storage modulus: measured by DMA (Dynamic Mechanical Analysis) method

* Adhesion: Peel strength (90 degree peel, width 1cm) measured by Instron Co., Ltd. (Universer test machine)

* Adhesion: Measured by tackness tester (diameter: 5mm)

The moisture absorption rate and OLED defect level of the organic light emitting diodes were measured by the following method, and the results are shown in Table 2.

(1) Moisture absorption efficiency: The weight difference between the weight after absorption and the weight before absorption after storage at 85 ° C and 85% moisture absorption conditions were divided by the weight before absorption.

(2) OLED defect degree: After constructing OLED device and storing 85 ℃ / 85%, 300hr, dark spot and OLED device defect were observed.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Moisture absorption rate (wt%) 5wt% 13wt% 12wt% 0wt% 10 wt% 12wt% OLED bad
Whether ok ok ok N / G N / G N / G

As shown in Table 2, in the case of Example 1-3 to which the Ca moisture absorption layer and the specific filler layer is applied, the moisture absorption rate is superior to that of Comparative Example 1 to which only the filler layer is applied, there is no warpage, and OLED defects do not occur. You can see that it does not. In Comparative Example 2, in which only the Ca moisture absorption layer was applied, the moisture absorption rate was excellent, but warpage and OLED defects occurred. In addition, in the case of Comparative Example 3 in which the CaO layer was applied as the moisture absorption layer instead of the Ca moisture absorption layer, a dark spot and a scratch problem occurred.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings and tables, the present invention is not limited to the above embodiments, but may be manufactured in various forms, and common knowledge in the art to which the present invention pertains. Those skilled in the art can understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. It is therefore to be understood that the embodiments described above are in all respects illustrative and not restrictive.

10: substrate 20: organic light emitting unit
30: filler layer 40: moisture absorption layer
50: encapsulation base 100: moisture absorption filler

Claims (21)

A moisture absorption layer formed on the encapsulation substrate; And
A filler layer formed on the moisture absorption layer;
Hygroscopic filler for organic light-emitting device comprising a.

The hygroscopic filler for an organic light emitting device according to claim 1, wherein the filler layer has a storage modulus of 0.1 to 100 MPa measured by DMA (Dynamic Mechanical Analysis).
The hygroscopic filler for an organic light emitting device according to claim 1, wherein the filler layer has a glass transition temperature of -50 to 80 ° C.
The method of claim 1, wherein the filler layer is a moisture absorption filler for an organic light emitting device, characterized in that the water absorption by the following formula: 0 ~ 10 wt%:

The hygroscopic filler for an organic light emitting device according to claim 4, wherein the filler layer has a water absorption of 0.1 to 5 wt%.
The hygroscopic filler for an organic light emitting device according to claim 1, wherein the filler layer is formed continuously.
The hygroscopic filler for an organic light emitting device according to claim 1, wherein the filler layer is formed discontinuously.
The hygroscopic filler for an organic light emitting device according to claim 7, wherein the filler layer is patterned.
The hygroscopic filler for an organic light emitting device according to claim 1, wherein the filler layer has an adhesive force of 100 gf / cm or more and an adhesive force of 10 gf / mm or more.
The hygroscopic filler for an organic light emitting device according to claim 1, wherein the filler layer is porous.
The method of claim 1, wherein the filler layer is a vinyl acetate resin (PVAc) resin, polyvinyl pyrrolidone (PVP) resin, polyester resin, polyolefin resin, (meth) acrylate resin, polycarbonate resin , Acrylonitrile resin, cellulose acetate, epoxy resin, phenoxy resin, siloxane resin, sulfone resin, polyamide resin, polyurethane resin, polyvinyl resin, urethane acrylate resin, florin resin, A hygroscopic filler for an organic light emitting device, characterized in that made of a polymer resin containing at least one from the group consisting of rubber.
12. The hygroscopic filler for organic light emitting device according to claim 11, wherein the polymer resin contains a hydrophilic group.
The moisture absorption filler of claim 1, wherein a thickness ratio of the moisture absorption layer and the filler layer is 1: 2 to 50. 3.
The hygroscopic filler for an organic light emitting device according to claim 1, wherein the encapsulation substrate is formed to face the organic light emitting device, and is metal or glass.
Depositing a calcium hygroscopic layer on one surface of the encapsulation substrate; And
Forming a filler layer on the calcium hygroscopic layer;
Method for producing a hygroscopic filler for an organic light emitting device comprising a step.
The method of claim 15, wherein the filler layer has a storage modulus of 0.1 to 100 MPa and a water absorption of 0 to 10 wt% according to the following formula measured by Dynamic Mechanical Analysis (DMA):

The method of claim 16, wherein the filler layer is formed by applying or laminating on the calcium hygroscopic layer.
An organic light emitting device comprising a moisture absorbing filler for an organic light emitting device according to any one of claims 1 to 14.
Board;
An organic light emitting unit formed on one surface of the substrate and including a first electrode, an organic light emitting layer, and a second electrode;
An encapsulation substrate formed to face the organic electroluminescent unit at intervals so as to protect the organic electroluminescent unit; And
It includes a drying means disposed between the encapsulation substrate and the organic electroluminescent unit,
The drying means is an organic light-emitting device, characterized in that the hygroscopic filler according to any one of claims 1 to 14.
The organic light emitting diode of claim 19, wherein the hygroscopic filler is not in contact with the organic light emitting unit.
20. The organic light emitting device of claim 19, wherein the filler layer of the hygroscopic filler is in contact with the organic light emitting unit.

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