KR102029683B1 - A coating solution for forming a thin film of an organic light emitting device for solution process, its manufacturing method and an organic light emitting device manufactured thereby - Google Patents

Abstract

One embodiment of the present invention is applied to one surface of the electrode using a compound for forming a thin film having at least two functional groups containing a pyrimidine ring at the end and then heat treated to form a thin film, after the thin film is formed Even if the organic solvent is applied again, the thin film is not dissolved by hydrogen bonding between the functional groups including the pyrimidine ring, thereby providing a coating liquid for forming an organic device thin film, wherein the multilayer thin film can be formed. do.

Description

A coating solution for forming an organic device thin film for a solution process, a method of manufacturing the same, and an organic device manufactured by the same, and a method of manufacturing the organic device, and a method for manufacturing the same. THEREBY}

The present invention relates to a coating liquid for forming an organic device thin film for a solution process, a manufacturing method thereof and an organic device produced thereby. More particularly, the present invention relates to an organic device thin film forming coating liquid comprising a compound for forming a thin film having at least two functional groups including a pyrimidine ring at its end, a method for preparing the same, and an organic device manufactured thereby.

In general, an organic device, particularly an organic light emitting device, is inserted into an organic thin film between a pair of electrodes, using the low molecular weight organic thin film or polymer organic thin film to distinguish the organic thin film as a component.

Japanese Patent Laid-Open No. 2006-156847 (hereinafter referred to as Prior Art 1) discloses an organic compound and a technique for manufacturing an organic light emitting device including an organic film having a single layer structure by depositing the same on a substrate by vacuum deposition.

Vacuum evaporation is a principle of forming a thin film by heating a sample in a high temperature vacuum atmosphere by heating and subliming the sample to a solid on a relatively low temperature substrate.

However, there is a problem that expensive vacuum deposition equipment is required and it may be difficult to manufacture devices in large areas.

In addition, in the case of constituting the polymer organic thin film, an organic device including only the polymer organic thin film having a single layer structure may be manufactured. However, in the case of the single layer structure, the driving voltage, luminance, and luminous efficiency of the organic device may be higher than those of using the multilayer organic thin film. There was a problem of falling.

In addition, the monomolecular compound for organic devices applied to the conventional deposition method has a low solubility in a solvent, so that a polymer material that can form a thin film with high solubility and itself can be formed by applying a solution additionally added to the solvent to cure. It is common to use a method, in which the solution may dissolve another layer in the organic device. To solve this problem, it is necessary to perform a separate insolubilization process, which is inefficient in terms of cost and time. There was a problem.

Japanese Patent Laid-Open No. 2006-156847

The technical problem to be achieved by the present invention is to form a thin film by using a compound for forming a thin film having at least two functional groups containing a pyrimidine ring at the end of the thin film is not dissolved in an organic solvent again It is an object of the present invention to provide a coating liquid for forming an organic device thin film capable of forming a multilayer thin film having excellent characteristics, a method of manufacturing the same, and a technology related to an organic device manufactured thereby.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. There will be.

In order to achieve the above technical problem, one embodiment of the present invention includes a compound for forming a thin film having at least two or more functional groups including a pyrimidine ring at the end and an organic solvent for dissolving the compound for forming a thin film, It provides a coating liquid for forming an organic device thin film, characterized in that to form a three-dimensional network structure by hydrogen bonding between the functional group containing the pyrimidine ring.

In an embodiment of the present invention, after forming a thin film with the coating liquid for forming an organic device thin film, even if an organic solvent is applied on the thin film, the thin film is not dissolved by the hydrogen bond, thereby forming a multilayer thin film. It may be a coating liquid for forming an organic device thin film.

In an embodiment of the present invention, the functional group including the pyrimidine ring may be a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of a pyrimidine-based functional group and a purine-based functional group.

In an embodiment of the present invention, the pyrimidine-based functional group may be a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of the compounds represented by the following formula (1a) and (1b).

(In Chemical Formulas 1a to 1b,

R ₁ to R ₆ may be the same as or different from each other, and each independently H, D, F, Cl, Br, I, an amino group, linear alkyl having 1 to 12 carbon atoms, carboxylic acid having 1 to 10 carbon atoms, and 1 carbon atom To alcohols of 10 to 10 and alkyl halides of 1 to 10 carbon atoms.

In an embodiment of the present invention, the purine-based functional group may be a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of the compounds represented by the formula (2a) and formula (2e).

(In Chemical Formulas 2a to 2e,

R ₇ to R ₁₇ may be the same as or different from each other, and each independently H, D, F, Cl, Br, I, an amino group, straight chain alkyl having 1 to 12 carbon atoms, carboxylic acid having 1 to 10 carbon atoms, and 1 carbon atom To alcohols of 10 to 10 and alkyl halides of 1 to 10 carbon atoms.

In an embodiment of the present invention, the compound for forming a thin film is a silicone-based compound having at least two or more functional groups containing a pyrimidine ring at the terminal and a force having at least two or more functional groups containing a pyrimidine ring at the terminal It may be a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of the pin oxide compound.

In an embodiment of the present invention, the thin film forming compound may be a coating liquid for forming an organic device thin film, characterized in that it has any one or more of the characteristics selected from the hole transporting properties, electron transporting properties, hole blocking properties and luminescence properties. .

In an embodiment of the present invention, when the compound for forming a thin film has luminescent properties, the compound for forming a thin film includes at least one compound selected from among a hole transport type compound, an electron transport type compound, and a bipolar transport type compound. It may be a coating liquid for forming an organic device thin film.

In an embodiment of the present invention, the organic solvent is methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol (tert- butyl alcohol), dimethylformamide, dimethylacetamide, ketone, acetone, diacetone alcohol, keto-alcohol, dioxane, ether, polyethylene glycol, polypropylene glycol, polyalkylene glycol, ethylene glycol, propylene glycol, butylene glycol , Triethylene glycol, hexylene glycol, diethylene glycol, glycerol, ethylene glycol monomethyl ether, diethylene glycol methyl ether, triethylene glycol monomethyl ether, 2-pyrrolidone, toluene, xylene, chlorobenzene, dichlorobenzene, Chloroform, dichloromethane, dichloroethane, gamma butyllactone, butyl cellosolve, cyclohexane, N-methyl-2-pyrrolidone, cyclohexanone, tetrahydro Furan, carbon tetrachloride, tetrachloroethane, octylbenzene, dodecylbenzene, quinoline, trichlorobenzene, nitrobenzaldehyde, nitrobenzene, carbon disulfide, 2-heptanone, benzene, terpineol, butylcarbitol acetate and ion exchange It may be a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more selected from water (pure).

In order to achieve the above technical problem, another embodiment of the present invention is prepared by adding a precursor, a reactant, an inorganic base and a catalyst to a solvent and reacting to prepare an intermediate and the intermediate, crosslinkable compound, inorganic base in the solvent And adding a catalyst and reacting to prepare a compound for forming a thin film, wherein the crosslinkable compound includes a compound including a substituted or unsubstituted pyrimidine ring, and the compound for forming a thin film is pyrimidine at its end. It provides a method for producing a coating liquid for forming an organic device thin film, characterized in that it comprises at least two functional groups including a ring.

In an embodiment of the present invention, the solvent may be a method for preparing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more selected from distilled water, dimethylformamide and dimethyl sulfoxide.

In an embodiment of the present invention, the precursor may be a method for preparing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more selected from silicon derivatives and phosphine oxide derivatives.

In an embodiment of the present invention, the reactant may be a method for preparing a coating solution for forming an organic device thin film, characterized in that the precursor and Suzuki coupling reaction is performed.

In an embodiment of the present invention, the catalyst may be a method for preparing a coating liquid for forming an organic device thin film, characterized in that it comprises a transition metal-based catalyst.

In an embodiment of the present invention, the inorganic base is a coating liquid preparation for forming an organic device thin film, characterized in that it comprises any one or more selected from potassium-based inorganic bases, cesium-based inorganic bases and sodium-based inorganic bases It may be a method.

In an embodiment of the present invention, the functional group containing the pyrimidine ring may be a method for preparing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of pyrimidine-based functional groups and purine-based functional groups.

In an embodiment of the present invention, the compound for forming a thin film is provided with at least two or more functional groups including a pyrimidine ring at the end of the force having at least two or more functional groups containing a pyrimidine ring at the terminal It may be a method for preparing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of the pin oxide compound.

In order to achieve the above technical problem, an embodiment of the present invention comprises the steps of preparing a compound for forming a thin film and an organic solvent having at least two functional groups including a pyrimidine ring at the terminal, the compound for forming a thin film Providing a coating liquid for forming a thin film by mixing with an organic solvent and forming a thin film for an organic device by applying the thin film forming coating liquid on a substrate and heat treatment to provide a method for forming an organic device thin film do.

In an embodiment of the present invention, the organic device thin film may be a method for forming an organic device thin film, characterized in that any one of a hole transport layer, an electron transport layer, a hole blocking layer and a light emitting layer.

In an embodiment of the present invention, the functional group including the pyrimidine ring may be a method for forming an organic device thin film comprising any one or more of a pyrimidine-based functional group and a purine-based functional group.

In an embodiment of the present invention, the compound for forming a thin film is a silicone-based compound having at least two or more functional groups containing a pyrimidine ring at the terminal and a force having at least two or more functional groups containing a pyrimidine ring at the terminal It may be a method of forming an organic device thin film comprising any one or more of a pin oxide compound.

In an embodiment of the present invention, the organic thin film forming method may be a hydrogen bond between the functional group containing the pyrimidine ring due to the heat treatment of the step of forming the organic device thin film.

In an embodiment of the present invention, after forming a thin film with the coating solution for forming a thin film, even if an organic solvent is applied on the thin film, the thin film is not dissolved by the hydrogen bond, thereby forming a multi-layer thin film. It may be a thin film forming method for an organic device.

In order to achieve the above technical problem, another embodiment of the present invention provides a thin film for an organic device formed by a method for forming a thin film for an organic device.

In order to achieve the above technical problem, another embodiment of the present invention is provided between the first electrode, the second electrode positioned to face the first electrode and the first electrode and the second electrode, the pyrimidine ring at the end An organic device thin film comprising a compound for forming a thin film having at least two or more functional groups comprising a, wherein the organic device thin film is on the thin film by hydrogen bonding between the functional groups containing the pyrimidine ring Provided is an organic device, wherein the thin film is not dissolved even when an organic solvent is applied.

In an embodiment of the present invention, the functional group including the pyrimidine ring may be an organic device comprising any one or more of pyrimidine-based functional groups and purine-based functional groups.

In an embodiment of the present invention, the compound for forming a thin film is a silicone-based compound having at least two or more functional groups containing a pyrimidine ring at the terminal and a force having at least two or more functional groups containing a pyrimidine ring at the terminal It may be an organic device comprising any one or more of a pin oxide compound.

In an embodiment of the present invention, the organic device thin film may be an organic device, characterized in that any one of a hole transport layer, an electron transport layer, a hole blocking layer and a light emitting layer.

As an effect of the present invention, in the manufacture of an organic thin film for an organic device, when two or more compound for forming a thin film having at least two functional groups including a pyrimidine ring at the terminal is provided, the pyrimidine ring It is possible to form a stable organic thin film by hydrogen bonding between the functional groups included.

In addition, in the case of the prior art, the deposition process used to solve the problem of poor solubility can be used only for a single molecule and is used only in a high temperature process, while adjacent layers are formed by a solution even when an organic thin film having a multilayer structure is manufactured through a solution process. It is possible to manufacture a stable multi-layer device without dissolving phenomenon.

Therefore, large area and low cost of the organic device can be achieved by using a solution process.

The effects of the present invention are not limited to the above-described effects, but should be understood to include all the effects deduced from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a graph showing the voltage (V) -current (I) of Preparation Example 1 according to an embodiment of the present invention.
Figure 2 is a graph showing the current efficiency according to the change in the current density of Preparation Example 1 according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to be "connected (connected, contacted, coupled)" with another part, it is not only "directly connected" but also "indirectly connected" with another member in between. Includes the case where In addition, when a part is said to "include" a certain component, this means that it may further include other components, without excluding the other components unless otherwise stated.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms “comprise” or “have” are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Hereinafter, a coating liquid for forming an organic device thin film will be described.

The coating liquid for forming an organic device thin film includes a compound for forming a thin film having at least two or more functional groups including a pyrimidine ring at an end thereof, and an organic solvent for dissolving the compound for forming a thin film, and including the pyrimidine ring. It may be a coating liquid for forming an organic device thin film, characterized in that to form a three-dimensional network structure by hydrogen bonding between functional groups.

The position at which the functional group including the pyrimidine ring is substituted may be anywhere as long as the terminal of the compound, and the terminal is a position where the functional group including the pyrimidine ring is positioned at an adjacent position such that no hydrogen bond is formed chemically. It means all positions which can be substituted for the compound except the case.

The functional group including the pyrimidine ring may include any one or more of pyrimidine-based functional groups and purine-based functional groups.

In an embodiment of the present invention, the pyrimidine-based functional group may be represented by the following formula.

(In Chemical Formulas 1a to 1b,

R ₁ to R ₆ may be the same as or different from each other, and each independently H, D, F, Cl, Br, I, an amino group, linear alkyl having 1 to 12 carbon atoms, carboxylic acid having 1 to 10 carbon atoms, and 1 carbon atom To alcohols of 10 to 10 and alkyl halides of 1 to 10 carbon atoms.

Specifically, the pyrimidine-based functional group formed from the compound represented by Chemical Formula 1a may be selected from a plurality of substance groups represented by the following chemical formulas, but is not limited thereto.

(The symbol (*) used in the above formula represents a bonding position with the compound for forming a thin film according to the present invention).

In addition, the pyrimidine-based functional group formed from the compound represented by Formula 1b may be selected from a plurality of substance groups represented by the following formula, but is not limited thereto.

 (The symbol (*) used in the above formula represents a bonding position with the compound for forming a thin film according to the present invention).

For example, the pyrimidine-based functional group may be represented by the following formula.

In an embodiment of the present invention, the purine-based functional group may be represented by the following formula.

(In Chemical Formulas 2a to 2e,

R ₇ to R ₁₇ may be the same as or different from each other, and each independently H, D, F, Cl, Br, I, an amino group, straight chain alkyl having 1 to 12 carbon atoms, carboxylic acid having 1 to 10 carbon atoms, and 1 carbon atom To alcohols of 10 to 10 and alkyl halides of 1 to 10 carbon atoms.

Specifically, the purine-based functional group formed from the compounds represented by Formulas 2a to 2e may be selected from a plurality of substance groups represented by the following Formulas, but is not limited thereto.

(The symbol (*) used in the above formula represents a bonding position with the compound for forming a thin film according to the present invention).

For example, the purine-based functional group may be represented as in the following formula.

In order to form each organic thin film constituting the existing organic device, a vapor deposition process was generally used, but in the case of the vapor deposition process, it is difficult to apply to organic devices having various shapes and sizes due to the difficulty in large area. To solve this problem, a solution process of dissolving a compound that forms a thin film in a solution and then forming a thin film was introduced. However, in the case of a solution process, in order to form an organic thin film in a multi-layered structure, after the organic thin film is formed, a solution process for continuously forming a thin film must be performed. There was a problem of not forming.

The present invention is a coating liquid for forming an organic device thin film that can be used in a solution process that solves the above problems, and after forming a thin film with the coating liquid for forming an organic device thin film, for forming a thin film containing an organic solvent on the thin film Even when the coating liquid is applied to the surface of the thin film, it can be maintained without being dissolved again.

This is a functional group containing two or more pyrimidine rings located at the terminal of the compound for forming a thin film is a hydrogen bond between the functional groups containing the pyrimidine ring by a heat treatment reaction, thereby dissolving between the compounds forming a thin film This is because the phenomenon does not occur.

In an embodiment of the present invention, the compound for forming a thin film may have a hole transport property. Holes are imaginary particles that carry positive (+) charges and behave like electrons, meaning they carry current. A hole injection layer (HIL) is a layer that allows holes to easily enter a light emitting layer as a layer closest to an anode in a positive charge OLED stacked light emitting structure. Hole Transfer Layer (HTL) is a layer that moves when a hole coming from the hole injection layer is subjected to a DC voltage at both ends.

The thin film compound having the hole transporting property includes a silicon compound having at least two or more functional groups including a pyrimidine ring at the terminal and a phosphine oxide compound having at least two or more functional groups including a pyrimidine ring at the terminal. It may be any one or more of. However, the materials are just examples and the material of the hole transport layer is not limited thereto.

For example, the silicon compound may be represented by the following formula.

At least two functional groups including a pyrimidine ring may be substituted at any terminal of the rings constituting the silicon compound.

As an example for this, the silicone-based compound in which the functional group containing the pyrimidine ring is substituted at the terminal formed by the substitution of the functional group containing the pyrimidine ring at the terminal of the silicone-based compound represented by (3-8) Can be displayed as:

In another example, the phosphine oxide-based compound may be represented by the following formula.

A functional group including a pyrimidine ring may be substituted at a terminal portion of any of the benzenes constituting the phosphine oxide compound.

As an example of this, a phosphine oxide system in which a functional group including a pyrimidine ring is substituted at a terminal formed by substituting a functional group including a pyrimidine ring at a terminal of the phosphine oxide compound represented by (4-7). The compound may be represented by the following formula.

In an embodiment of the present invention, the compound for forming a thin film may have electron transport characteristics. Thin film layers having electron transport characteristics in organic devices include an electron injection layer (EIL) and an electron transport layer (ETL). The electron injection layer is a layer that allows electrons to easily enter a light emitting layer as a layer closest to a cathode in a positive charge OLED stacked light emitting structure. The electron transport layer is a layer that moves when electrons coming from the electron injection layer are subjected to a DC voltage at both ends.

The thin film compound having the electron transporting property is a silicon-based compound having at least two or more functional groups containing a pyrimidine ring at the terminal and a phosphine oxide compound having at least two or more functional groups containing a pyrimidine ring at the terminal. It may be any one or more of. However, the materials are just examples and the material of the electron transport layer is not limited thereto.

For example, the silicon compound may be represented by the following formula.

At least two functional groups including a pyrimidine ring may be substituted at any terminal of the rings constituting the silicon compound.

As an example for this, the silicone-based compound in which the functional group containing the pyrimidine ring is substituted at the terminal formed by the substitution of the functional group containing the pyrimidine ring at the terminal of the silicone-based compound represented by (3-8) Can be displayed as:

In another example, the phosphine oxide-based compound may be represented by the following formula.

A functional group including a pyrimidine ring may be substituted at a terminal portion of any of the benzenes constituting the phosphine oxide compound.

As an example of this, a phosphine oxide system in which a functional group including a pyrimidine ring is substituted at a terminal formed by substituting a functional group including a pyrimidine ring at a terminal of the phosphine oxide compound represented by (4-7). The compound may be represented by the following formula.

In an embodiment of the present invention, the thin film forming compound may have a hole blocking property. The thin film layer having the hole blocking property in the organic device includes a hole blocking layer (HBL). The hole blocking layer may be positioned between the light emitting layer and the cathode.

The thin film compound having the hole blocking property may be a silicon compound having at least two or more functional groups including a pyrimidine ring at a terminal thereof, and a phosphine oxide compound having at least two or more functional groups including a pyrimidine ring at a terminal thereof. It may be any one or more of. However, the materials are just examples and the material of the hole blocking layer is not limited thereto.

For example, the silicon compound may be represented by the following formula.

At least two functional groups including a pyrimidine ring may be substituted at any terminal of the rings constituting the silicon compound.

As an example for this, the silicone-based compound in which the functional group containing the pyrimidine ring is substituted at the terminal formed by the substitution of the functional group containing the pyrimidine ring at the terminal of the silicone-based compound represented by (3-8) Can be displayed as:

In another example, the phosphine oxide-based compound may be represented by the following formula.

A functional group including a pyrimidine ring may be substituted at a terminal portion of any of the benzenes constituting the phosphine oxide compound.

As an example of this, a phosphine oxide system in which a functional group including a pyrimidine ring is substituted at a terminal formed by substituting a functional group including a pyrimidine ring at a terminal of the phosphine oxide compound represented by (4-7). The compound may be represented by the following formula.

In an embodiment of the present invention, the compound for forming a thin film may have light emission characteristics. In the organic device, a thin film layer having light emission characteristics includes an emission layer (EML). The emission layer is a layer in which holes and electrons are combined to convert quantum and thermal energy to emit light, and may emit light of various wavelengths according to the type of material.

The light emitting layer is a layer in which both electrons and holes exist, and is generally composed of a compound having an electron donating functional group and an electron withdrawing functional group in one molecule. However, if only the optical band gap energy is sufficient, the light emitting layer can emit light. It can be divided into transport type, electron transport type and bipolar transport type. Therefore, the compound for an organic thin film forming the light emitting layer may be one compound selected from a hole transport type compound, an electron transport type compound, and a bipolar transport type compound.

The compound for a thin film having the luminescence property is a silicone-based compound having at least two or more functional groups including a pyrimidine ring at the terminal and a phosphine oxide compound having at least two or more functional groups including a pyrimidine ring at the terminal. It may be any one or more. However, the materials are just examples and the material of the emission layer is not limited thereto.

For example, the silicon compound may be represented by the following formula.

At least two functional groups including a pyrimidine ring may be substituted at any terminal of the rings constituting the silicon compound.

As an example for this, the silicone-based compound in which the functional group containing the pyrimidine ring is substituted at the terminal formed by the substitution of the functional group containing the pyrimidine ring at the terminal of the silicone-based compound represented by (3-8) Can be displayed as:

In another example, the phosphine oxide-based compound may be represented by the following formula.

A functional group including a pyrimidine ring may be substituted at a terminal portion of any of the benzenes constituting the phosphine oxide compound.

As an example of this, a phosphine oxide system in which a functional group including a pyrimidine ring is substituted at a terminal formed by substituting a functional group including a pyrimidine ring at a terminal of the phosphine oxide compound represented by (4-7). The compound may be represented by the following formula

In an embodiment of the present invention, the organic solvent is methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol (tert- butyl alcohol), dimethylformamide, dimethylacetamide, ketone, acetone, diacetone alcohol, keto-alcohol, dioxane, ether, polyethylene glycol, polypropylene glycol, polyalkylene glycol, ethylene glycol, propylene glycol, butylene glycol , Triethylene glycol, hexylene glycol, diethylene glycol, glycerol, ethylene glycol monomethyl ether, diethylene glycol methyl ether, triethylene glycol monomethyl ether, 2-pyrrolidone, toluene, xylene, chlorobenzene, dichlorobenzene, Chloroform, dichloromethane, dichloroethane, gamma butyllactone, butyl cellosolve, cyclohexane, N-methyl-2-pyrrolidone, cyclohexanone, tetrahydro Furan, carbon tetrachloride, tetrachloroethane, octylbenzene, dodecylbenzene, quinoline, trichlorobenzene, nitrobenzaldehyde, nitrobenzene, carbon disulfide, 2-heptanone, benzene, terpineol, butylcarbitol acetate and ion exchange It may include one or more solvents selected from water (pure).

However, it is not limited to the solvents listed above, and in the case of the solvent used in the solution process, any kind may be used. The solvents are different from the vapor deposition process, and according to the conventional solution process, the organic thin film formed by the organic solvent may be dissolved, but according to the present invention, the thin film may be formed by hydrogen bonding between functional groups containing pyrimidine rings. Since it is not easily dissolved and maintains a constant form, it may be possible to laminate two or more organic thin films in a solution process.

Hereinafter, a method of preparing a coating liquid for forming an organic device thin film will be described.

The method of preparing a coating solution for forming an organic device thin film includes preparing an intermediate by adding a precursor, a reactant, an inorganic base, and a catalyst to a solvent, and reacting the intermediate, a crosslinkable compound, an inorganic base, and a catalyst with a solvent. To prepare a compound for forming a thin film, wherein the crosslinkable compound includes a compound including a substituted or unsubstituted pyrimidine ring, and the compound for forming a thin film includes a functional group including a pyrimidine ring at a terminal thereof. At least two or more may be provided.

First, a precursor, a reactant, an inorganic base and a catalyst are added to a solvent and reacted to prepare an intermediate.

The solvent may include any one or more selected from distilled water, dimethylformamide and dimethyl sulfoxide, but is selected from the group consisting of a non-polar solvent and a polar solvent which provide an atmosphere in which the precursors and reactants described below may be reacted. It may include more than one species.

For example, the solvent may be distilled water.

The precursor may be used without limitation as long as it is a precursor capable of forming a compound for forming a thin film, which is the final product of the preparation method, and specifically, may include any one or more selected from silicon derivatives and phosphine oxide derivatives.

For example, the precursor may be Bis (4-bromophenyl) -diphenylsiliane.

The reactant may include a material in which the reactant is subjected to a Suzuki coupling reaction with the precursor.

For example, the reactant may be 2-bromo-5-pyridineboronic acid.

The inorganic base may be a material for making a base condition so that the Suzuki coupling reaction is carried out under base conditions, and selected from the group consisting of potassium-based inorganic bases, cesium-based bases and sodium-based bases It may include one or more, but are not limited to.

For example, the inorganic base may be tri-tert-butylphosphonium tetrafluoroborate.

The catalyst may be a material capable of promoting a Suzuki coupling reaction between the reactant and the precursor. Specifically, the catalyst may include a transition metal catalyst, and in particular, a palladium catalyst among the transition metal catalysts may be used. . Since the palladium catalyst has very good chemoselectivity and regioselectivity, the palladium catalyst can be used as a catalyst for Suzuki coupling reaction.

For example, the palladium catalyst is Palladium (II) acetate (Pd (OAc) ₂ ), Tris (dibenzylideneacetone) dipalladium (0) (Pd- ₂ (dba) ₃ ), Palladium-tetrakis (triphenylphosphine) (Pd (PPh ₃ ) ₄ ) and [1,1′-Bis (diphenylphosphino) ferrocene] dichloropalladium (II) (PdCl ₂ (dppf)).

In an embodiment of the present invention, the preparing of the intermediate may be performed as in Scheme 1 below.

Scheme 1

Next, the intermediate, the crosslinkable compound, the inorganic base and the catalyst are added to the solvent and reacted to prepare a compound for forming a thin film.

The solvent may include any one or more selected from distilled water, dimethylformamide, and dimethylsulfoxide, but is selected from the group consisting of a nonpolar solvent and a polar solvent that provide an atmosphere in which a reaction between the intermediate and the crosslinkable compound may occur. It may include one or more kinds.

For example, the solvent may be dimethyl sulfoxide.

In the step, the intermediate prepared in the step of preparing the above-described intermediate is used as one reactant, and a crosslinkable compound is added to the intermediate to react between the intermediate and the crosslinkable compound to form a functional group including a pyrimidine ring. The compound for thin film formation provided with at least 2 or more can be manufactured. Therefore, the crosslinkable compound that reacts with the intermediate may include a material that reacts with the intermediate, and at the same time, it must include a material that can serve as a functional group. Specifically, the crosslinkable compound may include a compound including a substituted or unsubstituted pyrimidine ring.

Accordingly, the compound for forming a thin film may include a silicon compound having at least two functional groups including a pyrimidine ring at the terminal and a phosphine oxide compound having at least two functional groups including a pyrimidine ring at the terminal. It may include any one or more.

The inorganic base may be a material for making a base condition so that the reaction is carried out in the base conditions when the reaction is made, one type selected from the group consisting of potassium-based inorganic bases, cesium-based bases and sodium-based bases It may include but is not limited to the above.

For example, the inorganic base may be potassium phosphate.

The catalyst may be a material capable of promoting a reaction between the reactant and the precursor. Specifically, the catalyst may include a transition metal catalyst, and in particular, a palladium catalyst among the transition metal catalysts may be used. Since the palladium catalyst is very excellent in chemoselectivity and regioselectivity, the palladium catalyst can be used as a catalyst for the reaction.

For example, the palladium catalyst is Palladium (II) acetate (Pd (OAc) ₂ ), Tris (dibenzylideneacetone) dipalladium (0) (Pd- ₂ (dba) ₃ ), Palladium-tetrakis (triphenylphosphine) (Pd (PPh ₃ ) ₄ ) and [1,1′-Bis (diphenylphosphino) ferrocene] dichloropalladium (II) (PdCl ₂ (dppf)).

In an embodiment of the present invention, the preparing of the compound for forming a thin film may be performed as in Scheme 2 below.

Scheme 2

The preparation of the above-described intermediate may be omitted if the precursor can be directly reacted with the crosslinkable compound, and may proceed as shown in Scheme 3 below.

Scheme 3

Hereinafter, a method of forming an organic device thin film will be described.

The organic device thin film forming method comprises the steps of preparing a compound for forming a thin film and an organic solvent having at least two functional groups containing a pyrimidine ring at the end, by mixing the compound for forming a thin film with the organic solvent for forming a thin film It may include the step of preparing a coating solution and the coating solution for forming a thin film on a substrate and then heat-treating to form a thin film for an organic device.

The thin film forming compound having at least two functional groups including the pyrimidine ring is selected from among the hole transporting properties, the electron transporting properties, the hole blocking properties, and the luminescent properties as shown in the coating liquid for forming the organic device thin film. It may vary depending on which one of the characteristics, and the compound for each characteristic is the same as described above in the coating liquid for forming the organic device thin film, it will be omitted below.

In an embodiment of the present invention, the compound for forming a thin film is a material included in the coating liquid for forming an organic device thin film that can be used in a solution process, and after forming a thin film with the coating liquid for forming an organic device thin film, the thin film is formed on the thin film. Even when the coating liquid for forming a thin film including an organic solvent is applied to the surface of the thin film, it may be maintained without being dissolved again.

This is because a functional group including a pyrimidine ring located at the terminal of the compound for forming a thin film is hydrogen-bonded between the functional groups by a heat treatment reaction, and therefore, a phenomenon in which a compound is not dissolved between the compounds forming a thin film does not occur.

In an embodiment of the present invention, the organic solvent is methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol (tert- butyl alcohol), dimethylformamide, dimethylacetamide, ketone, acetone, diacetone alcohol, keto-alcohol, dioxane, ether, polyethylene glycol, polypropylene glycol, polyalkylene glycol, ethylene glycol, propylene glycol, butylene glycol , Triethylene glycol, hexylene glycol, diethylene glycol, glycerol, ethylene glycol monomethyl ether, diethylene glycol methyl ether, triethylene glycol monomethyl ether, 2-pyrrolidone, toluene, xylene, chlorobenzene, dichlorobenzene, Chloroform, dichloromethane, dichloroethane, gamma butyllactone, butyl cellosolve, cyclohexane, N-methyl-2-pyrrolidone, cyclohexanone, tetrahydro Furan, carbon tetrachloride, tetrachloroethane, octylbenzene, dodecylbenzene, quinoline, trichlorobenzene, nitrobenzaldehyde, nitrobenzene, carbon disulfide, 2-heptanone, benzene, terpineol, butylcarbitol acetate and ion exchange It may include one or more solvents selected from water (pure).

However, it is not limited to the solvents listed above, and in the case of the solvent used in the solution process, any kind may be used. The solvents are different from the vapor deposition process, and according to the conventional solution process, the organic thin film formed by the organic solvent may be dissolved, but according to the present invention, the thin film is formed by hydrogen bonding by a functional group containing a pyrimidine ring. Since it is not easily dissolved and maintains a constant form, it may be possible to laminate two or more organic thin films in a solution process.

In an embodiment of the present invention, it may further comprise the step of purifying the coating solution for forming a thin film.

In order to purify the coating liquid for thin film formation, it may be purified using column chromatography.

Column chromatography is a purification method in which an adsorbent or other suitable solid material is filled into a tube as a filler, the substance is injected thereon, and then separated through a tube. The tube used for this is called a chromatographic column or simply a column. As the filler, alumina, starch, cellulose and the like can be generally used.

In the present invention, a thin film forming coating solution containing a compound for forming a thin film having at least two functional groups including a pyrimidine ring may be injected into a column, and then purified by passing through the column.

In an embodiment of the present invention, since the compound for forming a thin film may have any one or more characteristics selected from among hole transporting properties, electron transporting properties, hole blocking properties, and luminescence properties, the compound for forming a thin film may be formed of an organic device. The organic device thin film layer selected from a hole transport layer, an electron transport layer, a hole blocking layer, and a light emitting layer may be formed.

In an embodiment of the present invention, due to the heat treatment of the step of forming the organic device thin film may be hydrogen bonding between the functional group containing the pyrimidine ring, the temperature in the heat treatment process is 50 ℃ to 400 ℃ Can be.

When the reaction is carried out in the above temperature range, hydrogen bonding between the compound for forming a thin film having at least two functional groups including the pyrimidine ring may occur well, thereby easily forming a thin film.

Hereinafter, the organic device thin film formed by the method for forming the organic device thin film will be described.

When the thin film for the organic device is formed by the above-described method for forming the thin film for the organic device, the thin film for the organic device is external due to hydrogen bonding between the thin film forming compound having at least two functional groups including the pyrimidine ring. It can be difficult to deform by stimulation. Therefore, even if another type of organic device thin film is further formed on the surface of the organic device thin film, the organic device thin film formed first may form two or more layers of organic device thin films without being dissolved by the organic solvent. .

Hereinafter, the organic device will be described.

The organic device includes a first electrode, a second electrode positioned to face the first electrode, and a thin film provided between at least two functional groups including a pyrimidine ring at a terminal thereof. A thin film for an organic device comprising a compound for forming, wherein the thin film for an organic device does not dissolve the thin film even when the organic solvent is applied to the thin film by hydrogen bonding between the functional groups containing the pyrimidine ring It may be characterized by.

The compound for forming a thin film having at least two functional groups including a pyrimidine ring at the terminal is selected from among the hole transporting properties, the electron transporting properties, the hole blocking properties, and the luminescence properties as shown in the coating liquid for forming the organic device thin film. It may vary depending on which one of the properties is selected, and the compound suitable for each property is the same as described above in the coating liquid for forming the organic device thin film, and thus the following description will be omitted.

In an embodiment of the present invention, the organic device thin film may be any one of a hole transport layer, an electron transport layer, a hole blocking layer and a light emitting layer. However, the present invention is not limited thereto, and all organic thin films used in the organic device may be included in the organic device thin film.

Hereinafter, the preparation examples and experimental examples of the present invention. However, these preparation examples and experimental examples are intended to explain the configuration and effects of the present invention in more detail, and the scope of the present invention is not limited thereto.

[Production Example 1]

1. Preparation of compound for thin film formation

(1) intermediate production

In a 100 mL round bottom flask, Bis (4-bromophenyl) -diphenylsiliane (1.5 g, 3.03 mmol) and 2-bromo-5-pyridineboronic acid (2.67 g, 12.12 mmol), Tris (dibenzylideneacetone) dipalladium (0) (0.075 g, 0.081 mmol) and Tri-tert-butylphosphonium tetrafluoroborate (0.048 g, 0.162 mmol) were added to prepare a first solution. Next, Tripotassium phosphate (1.98 g, 9.27 mmol) and 7.5 ml of distilled water are completely dissolved in a vial to prepare a second solution. The second solution was added to the first solution and stirred for 24 hours. After stirring, the intermediate was prepared by purification by column chromatography (MC: MeOH = 3: 1).

(2) Preparation of Compound for Thin Film Formation

Under nitrogen atmosphere, purified intermediate (0.5 g, 1 mmol), Orotic acid (0.4 g, 2.5 mmol), Potassium phosphate (0.82 g, 3.57 mmol), 18-crown-6 (0.35 g) in a 250 ml one-neck flask , 0.057 mol) and 100 ml of DMF were added and stirred, and the reaction was performed at 180 ° C. for 24 hours. After completion of the reaction, the organic layer was separated by extraction with MC / distilled water. After removing all of the solvent of the organic layer under reduced pressure, the compound was purified by column chromatography (MC: Hx = 1: 1) to prepare a compound for forming a thin film of the following formula.

2. Organic Device Manufacturing

Ultrasonic washing of the ITO substrate with distilled water and acetone, followed by spin coating PEODT: PSS ((Poly (3,4-ethylenedioxythiophene): poly (4-styrenesulfonate))) on the ITO substrate followed by vacuum at 120 ° C. After drying in an oven for 30 minutes to form a hole injection layer having a thickness of 30 nm, SMH-M2 of Formula 3 was dissolved in chlorobenzene and spin-coated on the hole injection layer, followed by vacuum coating at 120 ° C. in a vacuum oven. After drying for 30 minutes, a hole transport layer having a thickness of 20 nm was formed, and 8 wt% of SMH-M3 and Ir (mppy) ₃ of Formula 4 were dissolved in chlorobenzene and spin-coated on the hole transport layer. The light emitting layer was dried for 30 minutes in a vacuum oven of to form a light emitting layer having a thickness of 40 nm. The thin film-forming compound was dissolved in cholorobenzene and spin-coated on the light emitting layer, followed by drying in a vacuum oven at a temperature of 120 ° C. for 30 minutes. 30 nm thick An electron transport layer is formed, and an electrode is formed by vacuum deposition of LiF and Al on the electron transport layer, thereby manufacturing an organic device.

[Production Example 2]

1. Preparation of compound for thin film formation

In a 100 mL round bottom flask, add Orotic acid (0.67 g, 4.37 mmol) and 25 ml of DMSO and stir, add NaH (0.17 g, 7 mmol) slowly, remove the gas, and stir for 30 minutes. Manufacture. In another round bottom flask, 2,5-Bis (4-bromophenyl) -1,1-dimethyl-3,4-diphenylsilacyclopenta-2,4-diene (1 g, 1.75 mmol) and 25 ml of DMSO were added and stirred. Drop the first solution in a drop (drop) method and proceed the reaction at room temperature for 48 hours. After completion of the reaction, the organic layer was separated by extraction with MC / distilled water. After removing all the solvents of the organic layer under reduced pressure, the mixture was purified by column chromatography (MC: Hx = 1: 1) to prepare a compound for forming a thin film of the following Chemical Formula.

2. Organic Device Manufacturing

In the same manner as in Preparation Example 1, an organic device was manufactured.

Experimental Example 1

Energy level analysis of organic devices (voltage-current analysis)

1 is a graph showing the voltage (V) -current (I) of Preparation Example 1. FIG.

Referring to Figure 1, it can be seen that when the voltage is increased by a certain level, the current is increased rapidly, which shows that the organic device composed of the organic thin film manufactured by the solution process operates in a certain yield or more.

Experimental Example 2

2 is a graph showing the current efficiency according to the change in the current density of Preparation Example 1.

Referring to FIG. 2, when the current density is 0 mA / cm ² to 10 mA / cm ² , it can be seen that the current efficiency exhibits a maximum value of about 40 cd / A. This can be confirmed that the current efficiency is further improved compared to the conventional organic elements that do not use a compound for forming a thin film having at least two functional groups including a pyrimidine ring.

In addition, it can be seen that current efficiency decreases as the current density increases, which is a matter of adding a certain level of current density, and when the current density increases above a certain level, the current efficiency decreases. It can be seen that is the result of normal operation using a constant level of current.

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is represented by the following claims, and it should be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalents are included in the scope of the present invention.

Claims (28)

A compound for forming a thin film having at least two functional groups containing a pyrimidine ring at the terminal of the compound represented by Formula A or Formula B; And
It includes an organic solvent for dissolving the compound for forming a thin film,
Coating liquid for forming an organic device thin film, characterized in that to form a three-dimensional network structure by hydrogen bonding between the functional group containing the pyrimidine ring:
[Formula A]

[Formula B]

The method of claim 1,
After forming a thin film with the coating liquid for forming an organic device thin film, even if an organic solvent is applied on the thin film, the thin film is not dissolved by the hydrogen bond, thereby forming an organic device thin film. Coating solution.
The method of claim 1,
The functional group containing the pyrimidine ring coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of pyrimidine-based functional groups and purine-based functional groups.
The method of claim 3, wherein
The pyrimidine-based functional group is a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of the compounds represented by the formula (1a) and formula (1b):

(In Chemical Formulas 1a to 1b,
R ₁ to R ₆ may be the same as or different from each other, and each independently H, D, F, Cl, Br, I, an amino group, linear alkyl having 1 to 12 carbon atoms, carboxylic acid having 1 to 10 carbon atoms, and 1 carbon atom To alcohols of 10 to 10 and alkyl halides of 1 to 10 carbon atoms.
The method of claim 3, wherein
The purine-based functional group coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of the compounds represented by the formula (2a) and formula (2e):

(In Chemical Formulas 2a to 2e,
R ₇ to R ₁₇ may be the same as or different from each other, and each independently H, D, F, Cl, Br, I, an amino group, straight chain alkyl having 1 to 12 carbon atoms, carboxylic acid having 1 to 10 carbon atoms, and 1 carbon atom To alcohols of 10 to 10 and alkyl halides of 1 to 10 carbon atoms.
delete The method of claim 1,
The compound for forming a thin film is a coating liquid for forming an organic device thin film, characterized in that it has any one or more properties selected from among the hole transporting properties, electron transporting properties, hole blocking properties and luminescence properties.
The method of claim 7, wherein
When the thin film forming compound has luminescent properties, the thin film forming compound includes at least one compound selected from among a hole transport type compound, an electron transport type compound, and a bipolar transport type compound. Coating solution.
The method of claim 1,
The organic solvent is methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, dimethylformamide, Dimethylacetamide, ketone, acetone, diacetone alcohol, keto-alcohol, dioxane, ether, polyethylene glycol, polypropylene glycol, polyalkylene glycol, ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, hexylene glycol , Diethylene glycol, glycerol, ethylene glycol monomethyl ether, diethylene glycol methyl ether, triethylene glycol monomethyl ether, 2-pyrrolidone, toluene, xylene, chlorobenzene, dichlorobenzene, chloroform, dichloromethane, dichloroethane, Gamma butyl lactone, butyl cellosolve, cyclohexane, N-methyl-2-pyrrolidone, cyclohexanone, tetrahydrofuran, carbon tetrachloride, tetra In roloethane, octylbenzene, dodecylbenzene, quinoline, trichlorobenzene, nitrobenzaldehyde, nitrobenzene, carbon disulfide, 2-heptanone, benzene, terpineol, butylcarbitol acetate and ion exchange water (pure water) Coating liquid for forming an organic device thin film, characterized in that it comprises any one or more selected.
Preparing an intermediate by adding and reacting a precursor, a reactant, an inorganic base, and a catalyst to a solvent; And
Injecting the intermediate, the crosslinkable compound, the inorganic base and the catalyst in a solvent and reacting to prepare a compound for forming a thin film,
The crosslinkable compound includes a compound including a substituted or unsubstituted pyrimidine ring,
The compound for forming a thin film is a method for preparing a coating solution for forming an organic device thin film, characterized in that it comprises at least two functional groups containing a pyrimidine ring at the end of the compound represented by the formula (A) or formula (B):
[Formula A]

[Formula B]

The method of claim 10,
The solvent is a method for producing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more selected from distilled water, dimethylformamide and dimethyl sulfoxide.
The method of claim 10
The precursor is a method for producing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more selected from silicon derivatives and phosphine oxide derivatives.
The method of claim 10
The reactant is a method for producing a coating liquid for forming an organic device thin film, characterized in that the precursor and Suzuki coupling reaction.
The method of claim 10
The catalyst is a coating liquid manufacturing method for forming an organic device thin film, characterized in that it comprises a transition metal-based catalyst.
The method of claim 10
The inorganic base is a coating liquid manufacturing method for forming an organic device thin film, characterized in that it comprises any one or more selected from potassium-based inorganic bases, cesium-based inorganic bases and sodium-based inorganic bases.
The method of claim 10,
The functional group containing the pyrimidine ring is a method for producing a coating liquid for forming an organic device thin film, characterized in that it comprises any one or more of pyrimidine-based functional groups and purine-based functional groups.
delete Preparing a compound for forming a thin film and an organic solvent having at least two functional groups including a pyrimidine ring at a terminal of the compound represented by Formula A or Formula B;
Preparing a coating solution for forming a thin film by mixing the compound for forming a thin film with the organic solvent; And
A method of forming an organic device thin film, comprising: forming a thin film for an organic device by coating the thin film forming coating solution on a substrate and then performing heat treatment.
[Formula A]

[Formula B]

The method of claim 18
The organic device thin film forming method of any one of a hole transport layer, an electron transport layer, a hole blocking layer and the light emitting layer.
The method of claim 18,
The functional group including the pyrimidine ring comprises a pyrimidine-based functional group and a purine-based functional group of any one of the organic device thin film forming method.
delete The method of claim 18,
The method of forming a thin film for an organic device, characterized in that the hydrogen bonding between the functional group containing the pyrimidine ring is made by the heat treatment in the step of forming the thin film for the organic device.
The method of claim 22,
After forming a thin film with the coating liquid for forming a thin film, even if an organic solvent is coated on the thin film, the thin film is not dissolved by the hydrogen bond, thereby forming a multi-layer thin film for organic devices. .
An organic device thin film formed by the method for forming an organic device thin film of claim 18.
A first electrode;
A second electrode positioned to face the first electrode; And
For the organic device comprising a compound for forming a thin film provided between the first electrode and the second electrode, and having at least two functional groups containing a pyrimidine ring at the terminal of the compound represented by the formula (A) or (B) Contains a thin film,
The organic device thin film is an organic device characterized in that the thin film is not dissolved even if the organic solvent is applied on the thin film by hydrogen bonding between the functional group containing the pyrimidine ring:
[Formula A]

[Formula B]

The method of claim 25,
The functional group including the pyrimidine ring comprises an at least one of a pyrimidine-based functional group and a purine-based functional group.
delete The method of claim 25,
The organic device thin film is an organic device, characterized in that any one of a hole transport layer, an electron transport layer, a hole blocking layer and a light emitting layer.

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