KR20120074063A - Oled's moisture absorbent and oled using the same - Google Patents

Abstract

PURPOSE: A moisture absorbent for an organic electro luminescence light emitting device and the organic electro luminescence light emitting device using the same are provided to improve the durability and the life of the organic electro luminescence light emitting device by effectively blocking moisture and oxygen to an organic electro luminescence light emitting part. CONSTITUTION: A moisture absorbent for an organic electro luminescence light emitting device includes one or more compounds represented by chemical formulas 1 to 7. In chemical formulas 1 to 7, R or R1 is a C1 to C20 alkyl group, a C1 to C20 alkyl group, a C1 to C20 cycloalkyl group, a C1 to C20 alkyl group containing hetero elements(-NH-, -NHR'-, -S-, -O-), a C1 to C20 acyl group, an alcohol group, or an ether group; m and n are natural numbers; R' is a C1 to C10 linear, branched, or cyclic alkyl group; the moisture absorbent further includes nano-gold compounds. The nano-gold compounds are one or more selected from a group including calcium oxide(CaO), magnesium sulfate(MgSO_4), barium oxide(BaO), strontium oxide(SrO).

Description

Moisture absorber for organic EL device and organic EL device using same {OLED's moisture absorbent and OLED using the same}

The present invention relates to a moisture absorbent for an organic light emitting device and an organic light emitting device using the same, and more particularly, an absorbent absorbing moisture in a sealed space for protecting an internal device of the organic light emitting device and an organic light emitting light using the same. Relates to a device.

In the organic light emitting device, the organic light emitting unit is generally injected by injecting electrons and holes into the light emitting layer from the electron injection electrode and the hole injection electrode, respectively. It is a device that emits light when an exciton in which electrons and holes are combined falls from an excited state to a ground state.

Due to this principle, unlike the conventional thin film liquid crystal display device, since a separate light source is not required, there is an advantage in that the volume and weight of the device can be reduced.

In addition, the organic EL device exhibits high quality panel characteristics (low power, high brightness, high reaction rate, low weight). OELD is considered to be a powerful next-generation display that can be applied to portable communication products such as mobile communication terminal, CNS (Car Navigation System), personal digital assistances (PDA), Palm PC, etc.

In general, the organic light emitting device is composed of a transparent support substrate and a sealing substrate spaced apart from each other, the support substrate and the sealing substrate is encapsulated with each other by a sealing material (encapsulation). An array portion including a plurality of thin film transistors, gates, data lines, and storage capacitors is formed on an upper portion of the support substrate. have. In this case, the organic layer expresses the colors of red (R), green (G), and blue (B), and in general, red (R), green (G), and blue (B) colors for each pixel. A separate organic material emitting light is used as a pattern.

A filler in the form of a film is formed below the encapsulation substrate, and the filler in the form of a film is formed in the encapsulation substrate. That is, the filler serves to remove moisture that can penetrate into the seal formed by the support substrate and the sealing substrate.

In the bonding of the supporting substrate and the sealing substrate, a sealing material is placed on the edge of the sealing substrate. The sealing material is cured and acts as an adhesive to bond the supporting substrate and the sealing substrate to complete the organic light emitting device.

Since the organic light emitting device (OLED) is a self-luminous type, the viewing angle is wider than the LCD, the contrast is good, and since the backlight is not required, the organic light emitting device (OLED) can be reduced in weight and advantageous in terms of power consumption. In addition, it is easy to display video because it has a sensitive screen and quick response time compared to other displays, and unlike LCD, it is attracting attention as a next-generation display because it is composed of solid thin film, which is strong in vibration and has a relatively wide use temperature range.

The display substrate utilized in the organic EL device is important for gas permeability such as oxygen or moisture through the substrate represented by gas barrier properties. This is because the durability of the material constituting the display element is affected by the transmitted oxygen or moisture, and since the material of the light emitting layer reacts very sensitively to oxygen or moisture and deteriorates, organic electroluminescence is emitted by these intrusions. There is a problem in that the performance of the device is degraded and the lifespan is shortened so that the luminous efficiency sharply decreases.

Therefore, in the organic light emitting device, an encapsulation technique is generally used to block external moisture and oxygen from entering the organic light emitting device.

In general, it is placed inside the hermetic case and sealed with an adhesive polymer to protect the moisture sensitive organic electroluminescent device. At this time, since the adhesive polymer does not completely block the water permeation, a separate filler for absorbing moisture is disposed in the airtight case to remove the water continuously penetrating.

Commonly used filler is an organometallic compound synthesized by the reaction of a metal alkoxide and an organic group containing an alkyl group is used as a filler of an organic light emitting device. At this time, the filler can be protected from moisture while covering the entire device in the form of a film has the advantage of having transparency. These fillers, while meeting the performance of the filler used as an organic light emitting device, in the manufacture of a film made of an organic metal compound using a solvent and dried to remove, the remaining solvent remains unremovable There is a problem that the device is damaged by the organic material.

On the other hand, the conventional sealing method is formed by attaching a filler in the form of a film to the sealing substrate and the substrate and the sealing substrate on which the organic light emitting element is formed, the Republic of Korea Patent Publication No. 2002-0065124 and the sealing substrate; A moisture absorbent formed into a thin film on an inner surface of the sealing substrate; A sealing material formed at an edge of the sealing substrate; To provide an organic electroluminescent device comprising a light emitting substrate which is bonded to the sealing material of the sealing substrate and the sealing substrate is configured to seal the light emitting layer formed on the lower surface to prevent the penetration of moisture, to manufacture such an organic electroluminescent device As an encapsulation method, an organic electroluminescent device characterized by forming a moisture absorbent thin film on a sealing substrate is disclosed, and glass or plastic material is used as the sealing substrate. However, the patent has a limit in preventing the penetration of moisture and there is a risk of breakage during the manufacturing process or use is not suitable for practical production in the high durability and reliability is not high.

In addition, in manufacturing the organic light emitting device, the internal space is formed in a vacuum or filled with an inert gas to prevent the penetration of oxygen and moisture, the manufacturing process is complicated.

Therefore, in the inclusion of a moisture absorbent in the organic light emitting device, it has been desired to develop an organic light emitting device that can effectively block moisture and oxygen while preventing damage to the organic light emitting device and can be manufactured by a simple manufacturing process.

The present invention to solve the above problems is to provide an organic electroluminescent device that can effectively block moisture and oxygen to improve the durability and life.

Another object of the present invention is to provide a moisture absorbent that can minimize damage to the organic light emitting device by not using a solvent in the manufacture of the moisture absorbent.

Another object of the present invention is to provide an organic electroluminescent device which can be processed at room temperature and has a simple process.

In order to achieve the above object, the present invention provides a moisture absorbent for an organic light emitting device comprising at least one formula of the following [Formula 1] to [Formula 7].

[Formula 1]

[Formula 2]

(3)

[Formula 4]

[Chemical Formula 5]

[Formula 6]

[Formula 7]

(In the above Chemical Formulas 1 to 7, the organic group, R or R1 is C _{1 ~} C ₂₀ Alkyl group, C _{1 ~} C ₂₀ cycloalkyl group, heteroatom (-NH-,-NHR '-(R 'Is a C ₁ -C ₂₀ alkyl group, including C ₁ -C ₁₀ linear, branched, cyclic alkyl group -S-, -O-), C ₁ -C ₂₀ acyl group, alcohol, or ether ) And m and n are natural numbers.)

In addition, the present invention is a group of the organic group (R) or R1, hydrogen of the glycol series end, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol C ₁ Provided is a moisture absorbent for organic electroluminescent devices, which is an alkyl glycol ether substituted with C ₅ alkyl.

In addition, the present invention is selected from the group consisting of carboxylic acid (-COOH), primary or secondary amine (-NH ₂ , -NRH), thiol (SH) and nitro group (NO ₂ ) at one end of the alkyl glycol ether. It provides a moisture absorbent for an organic light emitting device, characterized in that one functional group.

The present invention also provides a saturated or unsaturated aliphatic hydroxyl group (OH), a carboxylic acid (-COOH), a primary or secondary amine (-NH ₂ , -NRH) having a C _{1 ~} C ₂₀ in the organic group, R or R 1 and It provides a moisture absorbent for an organic light emitting device, characterized in that it further comprises at least one functional group selected from the group consisting of thiol (SH).

In addition, the present invention is the moisture absorbent further comprises a nano metal compound, the nano metal compound is calcium oxide (CaO), magnesium sulfate (MgSO ₄ ), barium oxide (BaO) and strontium oxide (SrO) in the group consisting of 1 It provides a moisture absorbent for an organic light emitting device characterized in that it is further included.

In another aspect, the present invention provides a moisture absorbent for an organic light emitting device, characterized in that the mixing ratio of the nano-metal compound in the moisture absorbent is 10 to 40% by weight based on the moisture absorbent.

The present invention also provides a support substrate; An organic light emitting unit formed on one surface of the support substrate and including an organic light emitting layer between a pair of electrodes; An encapsulation substrate positioned above the organic light emitting part; And a sealing material for coupling the supporting substrate and the sealing substrate, wherein the sealing material and the organic light emitting part provide an organic light emitting device including a hygroscopic agent including one or more of the following formulas [Formula 1] to [Formula 7]. do.

[Formula 1]

[Formula 2]

(3)

[Formula 4]

[Chemical Formula 5]

[Formula 6]

[Formula 7]

(In the above Chemical Formulas 1 to 7, the organic group, R or R1 is C _{1 ~} C ₂₀ Alkyl group, C _{1 ~} C ₂₀ cycloalkyl group, heteroatom (-NH-,-NHR '-(R 'Is a C ₁ -C ₂₀ alkyl group, including C ₁ -C ₁₀ linear, branched, cyclic alkyl group -S-, -O-), C ₁ -C ₂₀ acyl group, alcohol, or ether ) And m and n are natural numbers.)

In addition, the present invention is a group of the organic group (R) or R1, hydrogen of the glycol series end, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol C ₁ Provided is an organic electroluminescent device, which is an alkyl glycol ether substituted with alkyl of C ₅ .

In addition, the present invention is selected from the group consisting of carboxylic acid (-COOH), primary or secondary amine (-NH ₂ , -NRH), thiol (SH) and nitro group (NO ₂ ) at one end of the alkyl glycol ether. It provides an organic light emitting device, characterized in that one functional group.

The present invention also provides a saturated or unsaturated aliphatic hydroxyl group (OH), a carboxylic acid (-COOH), a primary or secondary amine (-NH ₂ , -NRH) having a C _{1 ~} C ₂₀ in the organic group, R or R 1 and Provided is an organic electroluminescent device, characterized in that it further comprises at least one functional group selected from the group consisting of thiols (SH).

In addition, the present invention is the moisture absorbent further comprises a nano metal compound, the nano metal compound is calcium oxide (CaO), magnesium sulfate (MgSO ₄ ), barium oxide (BaO) and strontium oxide (SrO) in the group consisting of 1 It provides an organic electroluminescent device characterized in that it is further included.

In another aspect, the present invention provides an organic electroluminescent device characterized in that the mixing ratio of the nano-metal compound in the absorbent is mixed 10 to 40% by weight based on the absorbent.

In another aspect, the present invention provides an organic electroluminescent device, characterized in that the support substrate and the sealing substrate is the same material.

The present invention further includes a planarization layer that functions as a buffer layer between an upper surface of the support substrate and a lower surface of the organic light emitting unit, wherein the surface flatness Ra of the planarization layer is 0.5 to 5 nm. Provided is a light emitting device.

In another aspect, the present invention provides an organic electroluminescent device, characterized in that the organic electroluminescent unit is stacked between the electrode layer and the electrode layer, a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, an electron injection layer in order.

The organic light emitting diode absorbent according to the present invention has an effect of effectively blocking moisture and oxygen to the organic light emitting unit to improve durability and lifespan.

In addition, the moisture absorbent according to the present invention solves the problem that the device is damaged when there is a residual solvent due to the use of a solvent used in the organic electroluminescent device by preparing an organometallic compound without using a solvent.

In addition, by using the hygroscopic according to the present invention when manufacturing an organic light emitting device is a room temperature process, there is an advantage that the process is simplified.

1 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present invention.
2 is a plan view of an organic light emitting display device according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that, in the drawings, the same components or parts have the same reference numerals as much as possible. In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order not to obscure the subject matter of the present invention.

The terms " about ", " substantially ", etc. used to the extent that they are used herein are intended to be taken to mean an approximation to or in the numerical value of the manufacturing and material tolerances inherent in the meanings mentioned, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

The present invention provides a moisture absorbent for an organic light emitting device comprising at least one formula of the following [Formula 1] to [Formula 7].

(In the above Chemical Formulas 1 to 7, the organic group, R or R1 is C _{1 ~} C ₂₀ Alkyl group, C _{1 ~} C ₂₀ cycloalkyl group, heteroatom (-NH-,-NHR '-(R 'Is a C ₁ -C ₂₀ alkyl group, including C ₁ -C ₁₀ linear, branched, cyclic alkyl group -S-, -O-), C ₁ -C ₂₀ acyl group, alcohol, or ether ) And m and n are natural numbers.)

The above formulas are formulas consisting of silicone-based or epoxy-based. The silicone series and the epoxy series of the above formulas may each function as functional groups, and each of the silicone series and the epoxy series listed in Formulas 1 to 7 may be mixed and used in two or more compositions.

The moisture absorbent of the present invention is made of a monomer or oligomer containing a silicone-based or modified epoxy series, and the physical properties of the compound vary depending on the type and the addition ratio of the reactants, in particular, an organic group, R or R1. The type and composition ratio of the initial reactant are important because the change in viscosity and hygroscopicity is large depending on the type and amount of.

The moisture absorbent according to the present invention can effectively block moisture and oxygen in the organic light emitting device, thereby improving durability and lifespan of the organic light emitting device.

In the chemical formula used in the present invention, the organic group, R, or R1 may be selected from hydrogen of glycol-based ends such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, and tripropylene glycol. C _1? is preferably an alkyl glycol ether is substituted by a C ₅ alkyl.

In addition, the alkylglycol ether has one end selected from the group consisting of carboxylic acid (-COOH), primary or secondary amine (-NH ₂ , -NRH), thiol (SH) and nitro group (NO ₂ ). Use what is a functional group.

In addition, saturated or unsaturated aliphatic hydroxyl groups (OH), carboxylic acids (-COOH), primary or secondary amines (-NH2, -NRH) and thiol (SH) having C ₁ -C ₂₀ in the organic group, R or R1 More than one functional group selected from the group consisting of

On the other hand, the moisture absorbent of the present invention may further include a nano metal compound to increase the moisture absorption rate, the nano metal compound is calcium oxide (CaO), magnesium sulfate (MgSO ₄ ), barium oxide (BaO) and strontium oxide ( SrO) and the like may further include one or more. At this time, the mixing ratio of the nanometal compound added to the moisture absorbent is preferably mixed at about 10 to 40% by weight, and more preferably at 30% by weight, based on the moisture absorbent.

In addition, the nanometals are agglomerated due to unstable surface energy inherent to nanoparticles. Thus, the dispersion and maintenance of nanoparticles before use is an important factor.

The size of the nano metal compound is preferably nano size, because the addition of a metal compound larger than the micro size may cause breakage of the OLED organic material layer and inhibit the hygroscopic effect. In addition, the final sealing process may cause surface friction and resistance with the substrate, thereby degrading the device characteristics. The nano metal compound may be purchased directly from a manufacturer such as Aldrich Stream, but may also be manufactured and used directly using a bead mill. After grinding to hundreds of nanometers to several tens of micrometers through a dry method, a wet bead mill may be used to produce a size of about 20 nm to several hundred nanometers.

The moisture absorbent according to the present invention can effectively block moisture and oxygen from the organic electroluminescent unit.

In addition, the moisture absorbent according to the present invention may be manufactured without using a solvent, thereby solving the problem of damage to the device when there is a residual solvent due to the use of a bar used in the organic EL device.

In addition, the problem of reduction of the moisture absorption rate, which is the main physical property of the liquid type moisture absorbent prepared by the mixing and adjusting of the content may be caused. In order to solve this problem and to prepare the hygroscopic agent having high hygroscopicity, an hygroscopic binder may be additionally added to increase the hygroscopicity.

Next, an organic electroluminescent device utilizing the above absorbent will be described.

1 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present invention.

In an exemplary embodiment, an organic light emitting display device includes a support substrate 110, an organic light emitting unit 140 formed on one surface of the support substrate, that is, a support substrate, and the organic light emitting unit to block the organic light emitting unit from outside air. It is provided with the sealing substrate 120 located opposite to the 110.

In addition, the materials of the support substrate 110 and the sealing substrate 120 are not particularly limited, and glass or optical films may be used, or materials laminated with glass and optical films may be used.

The non-limiting optical film includes polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene sulfone (PES), transparent polyimide (PI), polyarylate (PAR), poly Any one selected from the group consisting of cyclic olefins (PCO), crosslinked epoxy, and crosslinked urethane films may be used.

The support substrate 110 and the sealing substrate 120 are preferably formed of the same material. The advantage of using the same material is that, firstly, since the support substrate 110 and the sealing substrate 120 are formed of the same material, the support substrate 110 and the sealing substrate are The thermal expansion coefficient of 120 is the same, which can improve the mechanical strength of the panel against temperature changes. Second, by forming the substrate using the same kind of glass or optical film, the panel can be thinner and lighter than in the case of employing a metal substrate. Third, since the substrate using glass or the optical film has a higher surface smoothness than the substrate made of metal or the like, it is difficult to generate a gap at the interface with the sealing material, thereby increasing the adhesive strength.

In addition, the support substrate 110 and the sealing substrate 120 may be bonded through the sealing material 160. The encapsulant 160 bonds the support substrate 110 and the encapsulation substrate 120 through a thermosetting adhesive or a UV curable adhesive, and may be positioned along an edge of the encapsulation substrate 120. The encapsulant 160 forms an encapsulant 160 in a width of 0.1 to 2 mm at an edge portion of the encapsulation substrate 120 in order to bond the support substrate 110 including the organic light emitting unit 140 and the encapsulation substrate 120. The sealant 160 may be formed by printing using a screen mask or by applying a sealant dispense or a syringe directly to a corresponding position. In one embodiment of the present invention was provided using a Nagase (XNR 5570) product as a UV (Ultra violate) curing adhesive provided in a rectangular frame shape installed on the outside of the light emitting area.

On the other hand, between the sealing material and the organic electroluminescent unit is characterized in that it is filled with the above-mentioned liquid-absorbent for the organic electroluminescent device.

By using the liquid absorbent 130 described above, the room temperature process is possible, and the process is simplified.

In addition, the liquid absorbent 130 may effectively block moisture and oxygen from the organic electroluminescent unit. The moisture absorbent does not necessarily need to be a transparent material because it is positioned between the organic light emitting unit 140 and the sealant 160 as shown in FIG. 1.

The moisture absorbent 130 may effectively block moisture and oxygen to improve durability and lifespan.

In addition, the conventional film-type moisture absorbent to form a film form using a solvent and to increase the temperature to dry the solvent, there is a problem that the remaining residual solvent damages the organic EL device due to the remaining residual solvent is not dried there was. However, the moisture absorbent 130 according to the present invention does not use a solvent to solve the problem due to the residual solvent.

Meanwhile, according to an embodiment of the present invention, a planarization layer functioning as a buffer layer may be formed on the upper surface of the support substrate 110. The flat layer may be obtained by partially hydrolyzing the composition for forming an organic or organic-inorganic hybrid layer to form a sol solution, and then coating and curing it on the support substrate 110 which is a transparent substrate. The coating method may be a method such as spin coating, roll coating, bar coating, dip coating, gravure coating, spray coating. The sol state curing method may be used, such as thermal curing, UV curing, infrared curing, high frequency heat treatment. The thickness after the flattening layer is cured is 0.1 µm to 50 µm, preferably 0.1 µm to 20 µm, and more preferably 0.1 µm to 10 µm. If the thickness is thinner than 0.1 μm, it is susceptible to failure due to pinhole defects, and suffers from a limitation in that leakage current occurs later. In addition, if the thickness exceeds 50 μm, cracks and surfaces may occur. There is a problem of uneven formation.

In the present invention, the planarization layer serving as the buffer layer is important to have a surface flatness of roughness Ra. If the planarization layer is not flat, defects occur when the connection electrode and the organic light emitting layer on the planarization layer are deposited, and thus leak. Current is generated and the lifetime of the organic light emitting part is limited. Accordingly, in the present invention, the surface flatness of the flat layer is preferably 0.5 nm to 5 nm, and more preferably 0.5 to 1 nm, based on the stylus method. In addition, the organic material having a roughness of about 5 nm to 50 nm or a root-mean-square roughness (RMS value) in the maximum peak-to-valley roughness in the present invention. It is desirable to provide an electroluminescent device. In this case, the luminance is increased at the same voltage, thereby improving the quality of the organic light emitting device.

Meanwhile, referring to the organic light emitting unit 140, the organic light emitting unit 140 is formed of an electrode layer and an organic layer, and a cathode electrode 221 for supplying the electrons and an electrode layer supply holes. The organic light emitting layer 223 is disposed so that the anode electrode 225 is opposed to each other, and is disposed between the cathode electrode 221 and the anode electrode 225 to emit light. A cathode electrode 221 is formed on the support substrate 110, an organic emission layer 223 is formed on the cathode electrode 221, and an anode electrode 225 is formed on the organic emission layer 223.

The cathode electrode 221 is formed by depositing Li, Ca, LiF / Ca, LiF / Al, Al, Mg, and compounds thereof toward the organic light emitting layer 223, and thereon, such as ITO, IZO, ZnO, or In ₂ O ₃ . The cathode electrode 221 may be formed by forming an auxiliary electrode or a bus electrode line with a conductive material.

An organic emission layer 223 may be formed on the cathode electrode 221, and an anode electrode 225 may be formed on the organic emission layer 223. The anode electrode 225 may be formed as a transparent electrode, for example, may be formed of ITO, IZO, ZnO or In ₂ O ₃ .

The cathode electrode 221 and the anode electrode 225 may be formed in a predetermined pattern. In the case of the active emission type, the cathode electrode 221 may be deposited on the entire surface. However, the present invention is not limited thereto and may be patterned.

The organic light emitting layer 223 disposed between the cathode electrode 221 and the anode electrode 225 may be a low molecular or high molecular organic layer. When the low molecular organic layer is used, a hole injection layer (HIL) and a hole transport layer (HTL) are used. , An organic emission layer (EML), an electron injection layer (EIL), an electron injection layer (ETL), and the like may be formed by stacking a single or a composite structure, and these low molecular weight organic layers may be vacuum It can be formed by the method of deposition.

In the case of the polymer organic layer, the structure may include a hole transporting layer (HTL) and a light emitting layer (EML). In this case, PEDOT is used as the hole transporting layer, and PPV (Poly-Phenylenevinylene) and polyfluorene are used as the light emitting layer. Polymer organic materials such as (Polyfluorene) are used and can be formed by screen printing or inkjet printing.

In the organic light emitting unit 140, as anode and cathode voltages are applied to the cathode electrode 221 and the anode electrode 225, holes injected from the anode electrode 225 are moved to the light emitting layer, and electrons are injected from the cathode electrode 221 to the light emitting layer. In this light emitting layer, electrons and holes recombine to generate excitons, and as the excitons change from an excited state to a ground state, fluorescent molecules in the light emitting layer emit light to form an image. The light emitting layer has a light emitting layer formed of a three-layer structure by sequentially stacking light emitting layers implementing red (R), green (G), and blue (B), or a light emitting layer having a complementary color relationship. It may be formed in a single layer structure consisting of a light emitting layer to implement.

2 is a plan view of an organic light emitting display device according to an embodiment of the present invention, and it can be seen that the sealing material is formed at the edge of the sealing substrate 120 in a rectangular frame shape.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be clear to those who have knowledge of.

Claims (15)

Hygroscopic agent for an organic light emitting device comprising the formula of at least one of the following [Formula 1] to [Formula 7].
[Formula 1]

(2)

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Formula 6]

[Formula 7]

(In the above Chemical Formulas 1 to 7, the organic group, R or R1 is C _{1 ~} C ₂₀ Alkyl group, C _{1 ~} C ₂₀ cycloalkyl group, heteroatom (-NH-,-NHR '-(R 'Is a C ₁ -C ₂₀ alkyl group, including C ₁ -C ₁₀ linear, branched, cyclic alkyl group -S-, -O-), C ₁ -C ₂₀ acyl group, alcohol, or ether ) And m and n are natural numbers.) The method of claim 1,
The organic group (organic group), R or to the type of R1 is ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, triethylene hydrogen of the glycol-based ends, such as propylene glycol C _1? C ₅ A moisture absorbent for organic electroluminescent elements, which is alkyl glycol ether substituted with alkyl. The method of claim 2,
One functional group selected from the group consisting of carboxylic acid (-COOH), primary or secondary amine (-NH ₂ , -NRH), thiol (SH) and nitro group (NO ₂ ) at one end of the alkyl glycol ether. An absorbent for an organic light emitting device, characterized in that. The method of claim 3,
Saturated or unsaturated aliphatic hydroxyl group (OH), carboxylic acid (-COOH), primary or secondary amine (-NH ₂ , -NRH) and thiol (SH) having C ₁ -C ₂₀ in the organic group, R or R1 An absorbent for an organic light emitting device, characterized in that it further comprises at least one functional group selected from the group consisting of. 5. The method according to any one of claims 1 to 4,
The moisture absorbent further comprises a nano metal compound, wherein the nano metal compound is at least one further included in the group consisting of calcium oxide (CaO), magnesium sulfate (MgSO ₄ ), barium oxide (BaO) and strontium oxide (SrO). A moisture absorbent for an organic light emitting device, characterized in that. The method of claim 5,
The mixing ratio of the nano-metal compound in the moisture absorbent is 10 to 40% by weight based on the moisture absorbent is characterized in that the organic electroluminescent device moisture absorbent. Support substrates; An organic light emitting unit formed on one surface of the support substrate and including an organic light emitting layer between a pair of electrodes; An encapsulation substrate positioned above the organic light emitting part; And including a sealing material for coupling the support substrate and the sealing substrate,
An organic electroluminescent device comprising a hygroscopic agent comprising at least one chemical formula of the following [Formula 1] to [Formula 7] between the sealing material and the organic electroluminescent unit.
[Formula 1]

(2)

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Formula 6]

[Formula 7]

(In the above Chemical Formulas 1 to 7, the organic group, R or R1 is C _{1 ~} C ₂₀ Alkyl group, C _{1 ~} C ₂₀ cycloalkyl group, heteroatom (-NH-,-NHR '-(R 'Is a C ₁ -C ₂₀ alkyl group, including C ₁ -C ₁₀ linear, branched, cyclic alkyl group -S-, -O-), C ₁ -C ₂₀ acyl group, alcohol, or ether ) And m and n are natural numbers.) The method of claim 7, wherein
The organic group (organic group), R or to the type of R1 is ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, triethylene hydrogen of the glycol-based ends, such as propylene glycol C _1? C ₅ An organic electroluminescent device, characterized in that the alkyl glycol ether substituted with alkyl. The method of claim 8,
One functional group selected from the group consisting of carboxylic acid (-COOH), primary or secondary amine (-NH ₂ , -NRH), thiol (SH) and nitro group (NO ₂ ) at one end of the alkyl glycol ether. An organic light emitting device, characterized in that. The method of claim 7, wherein
Saturated or unsaturated aliphatic hydroxyl group (OH), carboxylic acid (-COOH), primary or secondary amine (-NH2, -NRH) and thiol (SH) having C ₁ -C ₂₀ in the organic group, R or R1 Organic electroluminescent device characterized in that it further comprises at least one functional group selected from the group consisting of. The method according to any one of claims 7 to 10,
The moisture absorbent further comprises a nano metal compound, wherein the nano metal compound is at least one further included in the group consisting of calcium oxide (CaO), magnesium sulfate (MgSO ₄ ), barium oxide (BaO) and strontium oxide (SrO). An organic light emitting device, characterized in that. The method of claim 11,
Organic nano light emitting device, characterized in that the mixing ratio of the nano-metal compound is included in the absorbent is 10 to 40% by weight based on the absorbent. The method of claim 7, wherein
And the supporting substrate and the sealing substrate are made of the same material. The method of claim 7, wherein
And a planarization layer functioning as a buffer layer between an upper surface of the support substrate and a lower surface of the organic light emitting unit, wherein the surface flatness (Ra) of the planarization layer is 0.5 to 5 nm. The method of claim 7, wherein
The organic electroluminescent device of claim 1, wherein a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, and an electron injection layer are sequentially stacked between the electrode layer and the electrode layer.

Images