KR102413781B1 - Ink composition and method of manufacturing organic light emitting device - Google Patents

Abstract

The present specification is a solvent represented by Formula 1; and an ink composition including a charge transporting material or a light emitting material represented by Formula 2, and a method of manufacturing an organic light emitting device formed using the ink composition.

Description

Ink composition and organic light emitting device manufacturing method

The present specification is a solvent represented by Formula 1; and an ink composition including a charge transporting material or a light emitting material represented by Formula 2, and a method of manufacturing an organic light emitting device formed using the ink composition.

Efforts are being made to manufacture organic light emitting devices through a solution process, and economical and stable inkjet printing (Inkjet Printing) is required as the consumption of materials is minimized, devices are miniaturized, and the resolution of displays is increased, and precise patterns are required. A method of manufacturing an organic light emitting device through a printing) process is attracting attention. In the case of manufacturing an organic light emitting device by the conventional deposition process, it is difficult to form a large-sized panel, whereas when manufacturing the organic light emitting device by the inkjet printing process, there is an advantage that a large-sized panel can be formed. .

The ink composition used in the inkjet printing process should be capable of stable ejection, phase separation between a functional material such as a charge transport material or a light emitting material and a solvent, and form a uniform film during film formation.

Conventionally, a lot of ether solvents or hydrocarbon solvents having relatively low polarity have been used in the ink composition. For example, solvents such as phenoxytoluene and cyclohexylbenzene are used in the ink composition. was used. However, when the solvent is used as the main solvent, there is a limitation in increasing the solid content of the ink due to the low solubility of the functional material, and thus there is a problem that the process takes a long time, and it does not form a stable film such as phase separation occurs during drying. There was a problem that it couldn't. In addition, when the solubility of the solvent in the functional material is low, the amount of the functional material that can be dissolved in the ink is limited. Therefore, in order to obtain a desired thickness, the number of drops that must be dropped on the pixel increases, making it difficult to obtain a flat profile. and it is difficult to obtain the desired thickness.

Further, in the case of the solvent used in the ink composition, even if the solubility for the functional material is high, it must have a high boiling point in order to prevent the problem of drying of the nozzle part. For example, in the case of cyclohexanone, although it corresponds to a solvent having good solubility, when used in an ink composition due to a low boiling point, it is not suitable for the inkjet process because the nozzle part is dried.

Accordingly, there is a demand in the art to develop an ink composition that has excellent solubility in functional materials and includes a solvent having a high boiling point.

Korean Patent Laid-Open Publication No. 10-2016-0117249

An object of the present specification is to provide an ink composition usable in an organic light emitting device and a method for manufacturing an organic light emitting device using the same.

The present specification is a solvent represented by the following formula (1); And it provides an ink composition comprising a charge transport material or a light emitting material represented by the following formula (2).

[Formula 1]

In Formula 1,

X ₁ To X ₅ Are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted cycloalkenyl group; a substituted or unsubstituted alkoxy group; or a substituted or unsubstituted ester group, and at least one of X ₁ to X ₅ is a substituted or unsubstituted alkyl group; Or a substituted or unsubstituted alkoxy group,

R ₁ is a substituted or unsubstituted alkyl group.

[Formula 2]

In Formula 2,

L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted alkylene group; a substituted or unsubstituted cycloalkylene group; a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,

L is a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,

Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

R1 to R4 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

Y1 to Y4 are the same as or different from each other, and each independently hydrogen; Or a photocuring group or thermosetting group, Y1 to Y4 at least 2 is a photocuring group or thermosetting group,

n1 and n4 are each an integer from 0 to 4,

n2 and n3 are each an integer from 0 to 3,

When each of n1 to n4 is 2 or more, the substituents in parentheses are the same as or different from each other.

The present specification includes the steps of preparing a substrate; forming a cathode or an anode on the substrate; forming one or more organic material layers on the cathode or anode; and forming an anode or a cathode on the organic material layer, wherein the forming of the organic material layer comprises forming one or more organic material layers using the ink composition described above. to provide.

Since the ink composition according to an exemplary embodiment of the present specification has high solubility of the solvent for the functional material, the content of the functional material in the ink composition can be increased, and thereby, the number of ink drops can be reduced, thereby reducing the process time It has a shortening effect.

In addition, since the ink composition of the present invention has a high boiling point, no phase separation occurs during precipitation of functional materials or film formation, and stable discharge is possible, thereby forming a uniform film.

1 illustrates an example of an organic light emitting device according to an exemplary embodiment of the present specification.

Hereinafter, the present specification will be described in detail.

In the present specification, when a member is said to be located “on” another member, this includes not only a case in which a member is in contact with another member but also a case in which another member exists between the two members.

In the present specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

In the present specification, the term "combination of these" included in the expression of the Markush format means a mixed or combined state of two or more selected from the group consisting of the components described in the expression of the Markush format, wherein the It means to include one or more selected from the group consisting of components.

As used herein, the term "photocuring group or thermosetting group" may refer to a reactive substituent that cross-links compounds between compounds by exposure to heat and/or light. Crosslinking may be generated by linking radicals generated by decomposition of carbon-carbon multiple bonds and cyclic structures by heat treatment or irradiation with light.

Hereinafter, the substituents of the present specification will be described in detail.

는 다른 치환기 또는 결합부에 결합되는 부위를 의미한다.In this specification,

is another substituent or means a site bonded to the bonding portion.

As used herein, the term "substitution" means that a hydrogen atom bonded to a carbon atom of a compound is replaced with another substituent, and the position to be substituted is not limited as long as the position at which the hydrogen atom is substituted, that is, a position where the substituent is substitutable, is not limited, and two or more When substituted, two or more substituents may be the same as or different from each other. When two or more substituents are adjacent, adjacent groups may combine to form an aromatic or aliphatic ring.

As used herein, the term "substituted or unsubstituted" refers to deuterium; nitrile group; nitro group; hydroxyl group; carbonyl group; ester group; an alkyl group; cycloalkyl group; cycloalkenyl group; alkoxy group; alkenyl group; aryl group; amine group; and substituted or unsubstituted by one or more substituents selected from the group consisting of a heterocyclic group, or substituted or unsubstituted in which two or more substituents among the exemplified substituents are connected. For example, "a substituent in which two or more substituents are connected" may be a biphenyl group. That is, the biphenyl group may be an aryl group, and may be interpreted as a substituent in which two phenyl groups are connected.

In the present specification, the alkyl group may be linear or branched, and according to an exemplary embodiment, the alkyl group has 1 to 20 carbon atoms. According to another exemplary embodiment, the number of carbon atoms in the alkyl group is 1 to 10. According to another exemplary embodiment, the alkyl group has 1 to 6 carbon atoms. Specific examples of the alkyl group include, but are not limited to, a methyl group, an isopropyl group, a pentyl group, or a t-butyl group.

In the present specification, the alkenyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 2 to 40. According to an exemplary embodiment, the carbon number of the alkenyl group is 2 to 20. According to another exemplary embodiment, the carbon number of the alkenyl group is 2 to 10. According to another exemplary embodiment, the alkenyl group has 2 to 6 carbon atoms. Specific examples include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1- Butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2-( Naphthyl-1-yl)vinyl-1-yl, 2,2-bis(diphenyl-1-yl)vinyl-1-yl, stilbenyl group, styrenyl group, and the like, but are not limited thereto.

In the present specification, the alkoxy group may be a straight chain, branched chain or cyclic chain. The number of carbon atoms of the alkoxy group is not particularly limited, but may be 1 to 20 carbon atoms. According to another exemplary embodiment, the carbon number of the alkoxy group may be 1 to 10. Specifically, it may be a methoxy group or an ethoxy group, but is not limited thereto.

The substituents containing an alkyl group, an alkoxy group, and other alkyl group moieties described herein include both straight-chain or pulverized forms.

In the present specification, the number of carbon atoms of the carbonyl group is not particularly limited, but it is preferably from 1 to 20 carbon atoms. Specifically, it may be a methyl ketone group, but is not limited thereto.

In the present specification, in the ester group, oxygen of the ester group may be substituted with a linear, branched or cyclic alkyl group having 1 to 25 carbon atoms or an aryl group having 6 to 25 carbon atoms. Specifically, it may be a compound of the following structural formula, but is not limited thereto.

In the present specification, the cycloalkyl group is not particularly limited, but according to an exemplary embodiment, the cycloalkyl group has 3 to 40 carbon atoms. According to another exemplary embodiment, the carbon number of the cycloalkyl group is 3 to 30. According to another exemplary embodiment, the carbon number of the cycloalkyl group is 3 to 20. According to another exemplary embodiment, the cycloalkyl group has 3 to 6 carbon atoms. and a cyclohexyl group, but is not limited thereto.

In the present specification, the cycloalkenyl group is not particularly limited, but has 3 to 40 carbon atoms. According to another exemplary embodiment, the carbon number of the cycloalkenyl group is 3 to 20. Specifically, there is a cyclohexenyl group, but is not limited thereto.

In the present specification, the aryl group is not particularly limited, but may have 6 to 40, 6 to 30, or 6 to 20 carbon atoms. In one embodiment, the carbon number of the aryl group may be 6 to 12. It may be a monocyclic aryl group or a polycyclic aryl group. The aryl group may be a phenyl group, but is not limited thereto.

In the present specification, the heterocyclic group is a heterocyclic group including at least one of N, O, P, S, Si and Se as heteroatoms, and the number of carbon atoms is not particularly limited, but it is preferably from 2 to 60 carbon atoms. According to an exemplary embodiment, the heterocyclic group has 2 to 30 carbon atoms. According to an exemplary embodiment, the heterocyclic group has 2 to 20 carbon atoms. According to another exemplary embodiment, the number of carbon atoms of the heterocyclic group may be 6 to 30, or 6 to 20.

In the present specification, the description of the above-described heterocyclic group may be applied, except that the heteroaryl group is aromatic.

In the present specification, the arylene group may be selected from the examples of the above-described aryl group, except that it is a divalent group.

In the present specification, the alkylene group may be selected from the examples of the above-described alkyl group, except that the alkylene group is a divalent group.

In the present specification, the cycloalkylene group may be selected from among the examples of the cycloalkyl group, except that it is a divalent group.

In the present specification, the heteroarylene group may be selected from the examples of the heteroaryl group described above, except that it is a divalent group.

As used herein, the "adjacent" group means a substituent substituted on an atom directly connected to the atom in which the substituent is substituted, a substituent sterically closest to the substituent, or another substituent substituted on the atom in which the substituent is substituted. can For example, two substituents substituted at an ortho position in a benzene ring and two substituents substituted at the same carbon in an aliphatic ring may be interpreted as "adjacent" groups.

In the present specification, the ring formed by bonding adjacent groups to each other may be monocyclic or polycyclic, and may be a condensed ring of aliphatic, aromatic or aliphatic and aromatic, and may form a hydrocarbon ring or a heterocyclic ring.

The hydrocarbon ring may be selected from the examples of the cycloalkyl group or the aryl group, except for the non-monovalent group. The heterocycle may be aliphatic, aromatic, or a condensed ring of aliphatic and aromatic, and may be selected from examples of the heterocyclic group, except for non-monovalent groups.

In an exemplary embodiment of the present specification, a solvent represented by the following formula (1); And it provides an ink composition comprising a charge transport material or a light emitting material represented by the following formula (2).

[Formula 1]

In Formula 1,

X ₁ To X ₅ Are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted cycloalkenyl group; a substituted or unsubstituted alkoxy group; or a substituted or unsubstituted ester group, and at least one of X ₁ to X ₅ is a substituted or unsubstituted alkyl group; Or a substituted or unsubstituted alkoxy group,

R ₁ is a substituted or unsubstituted alkyl group.

[Formula 2]

In Formula 2,

L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted alkylene group; a substituted or unsubstituted cycloalkylene group; a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,

L is a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,

Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

R1 to R4 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

Y1 to Y4 are the same as or different from each other, and each independently hydrogen; Or a photocuring group or thermosetting group, Y1 to Y4 at least 2 is a photocuring group or thermosetting group,

n1 and n4 are each an integer from 0 to 4,

n2 and n3 are each an integer from 0 to 3,

When each of n1 to n4 is 2 or more, the substituents in parentheses are the same as or different from each other.

Since the solvent represented by Formula 1 includes an ester group, it has high polarity and has high solubility in the functional layer material. Due to this, it is possible to increase the concentration of the ink composition including the solvent and the functional layer material, and to reduce the number of drops that need to be filled in the pixel to form the functional layer film of the required thickness to be manufactured with the ink composition. This has the advantage of preventing overflow and reducing ink drying time and ink usage.

In addition, since the solvent represented by Formula 1 of the present invention has high solubility and good storage stability of the ink, the material does not precipitate during storage of the ink composition. Since aggregation of the functional layer material does not occur in the ink composition of the present invention, a film having a smooth and flat surface can be formed when the ink is dried.

In an exemplary embodiment of the present specification, X ₁ to X ₅ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted C 1 to C 20 alkyl group; a substituted or unsubstituted C 3 to C 40 cycloalkyl group; a substituted or unsubstituted C 3 to C 40 cycloalkenyl group; a substituted or unsubstituted C 1 to C 20 alkoxy group; or a substituted or unsubstituted ester group, and at least one of X ₁ to X ₅ is a substituted or unsubstituted C 1 to C 20 alkyl group; or a substituted or unsubstituted C 1 to C 20 alkoxy group.

In an exemplary embodiment of the present specification, X ₁ to X ₅ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted C 1 to C 10 alkyl group; a substituted or unsubstituted C 3 to C 20 cycloalkyl group; a substituted or unsubstituted C 3 to C 20 cycloalkenyl group; or a substituted or unsubstituted C 1 to C 10 alkoxy group, and at least one of X ₁ to X ₅ is a substituted or unsubstituted C 1 to C 10 alkyl group; or a substituted or unsubstituted C 1 to C 10 alkoxy group.

In an exemplary embodiment of the present specification, X ₁ to X ₅ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted methyl group; a substituted or unsubstituted methoxy group; or a substituted or unsubstituted ethoxy group, and at least one of X ₁ to X ₅ is a substituted or unsubstituted methyl group; a substituted or unsubstituted methoxy group; Or a substituted or unsubstituted ethoxy group.

In an exemplary embodiment of the present specification, X ₁ to X ₅ are the same as or different from each other, and each independently hydrogen; methyl group; methoxy group; or an ethoxy group, and at least one of X ₁ to X ₅ is a methyl group; methoxy group; or an ethoxy group.

In an exemplary embodiment of the present specification, R ₁ is a substituted or unsubstituted C 1 to C 20 alkyl group.

In an exemplary embodiment of the present specification, R ₁ is a substituted or unsubstituted C 1 to C 10 alkyl group.

In an exemplary embodiment of the present specification, R ₁ is a substituted or unsubstituted methyl group; a substituted or unsubstituted ethyl group; Or a substituted or unsubstituted propyl group.

In an exemplary embodiment of the present specification, R ₁ is a methyl group; ethyl group; or a profile group.

In an exemplary embodiment of the present specification, Chemical Formula 1 may have any one of the following structures.

In an exemplary embodiment of the present specification, L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted C 1 to C 20 alkylene group; a substituted or unsubstituted C 3 to C 40 cycloalkylene group; a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; or a substituted or unsubstituted C 2 to C 30 heteroarylene group.

In an exemplary embodiment of the present specification, L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted C 1 to C 10 alkylene group; a substituted or unsubstituted C 3 to C 20 cycloalkylene group; a substituted or unsubstituted arylene group having 6 to 20 carbon atoms; or a substituted or unsubstituted C 2 to C 20 heteroarylene group.

In an exemplary embodiment of the present specification, L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted C 1 to C 20 alkylene group; or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms.

In an exemplary embodiment of the present specification, L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted hexylene group; a substituted or unsubstituted heptylene group; or a substituted or unsubstituted phenylene group.

In an exemplary embodiment of the present specification, L1 to L4 are the same as or different from each other, and each independently a hexylene group; heptylene group; or a phenylene group substituted with a methyl group.

In an exemplary embodiment of the present specification, L1 is a phenyl group.

In an exemplary embodiment of the present specification, L2 is a hexylene group.

In an exemplary embodiment of the present specification, L2 is a heptylene group.

In an exemplary embodiment of the present specification, L2 is a phenylene group.

In an exemplary embodiment of the present specification, L2 is a phenylene group substituted with a methyl group.

In an exemplary embodiment of the present specification, L3 is a hexylene group.

In an exemplary embodiment of the present specification, L3 is a heptylene group.

In an exemplary embodiment of the present specification, L3 is a phenylene group.

In an exemplary embodiment of the present specification, L4 is a phenylene group.

In an exemplary embodiment of the present specification, L is a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; or a substituted or unsubstituted C 2 to C 30 heteroarylene group.

In an exemplary embodiment of the present specification, L is a substituted or unsubstituted arylene group having 6 to 20 carbon atoms; or a substituted or unsubstituted C 2 to C 20 heteroarylene group.

In the exemplary embodiment of the present specification, L is a substituted or unsubstituted arylene group having 6 to 12 carbon atoms.

In an exemplary embodiment of the present specification, L is a substituted or unsubstituted biphenylene group.

In an exemplary embodiment of the present specification, L is a biphenylene group.

In an exemplary embodiment of the present specification, Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted C6-C30 aryl group; or a substituted or unsubstituted heteroaryl group having 6 to 30 carbon atoms.

In an exemplary embodiment of the present specification, Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted C6-C20 aryl group; Or a substituted or unsubstituted heteroaryl group having 6 to 20 carbon atoms.

In an exemplary embodiment of the present specification, Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted phenylene group; a substituted or unsubstituted biphenylene group; or a substituted or unsubstituted naphthyl group.

In an exemplary embodiment of the present specification, Ar1 and Ar2 are the same as or different from each other, and each independently a phenylene group; biphenylene group; or a naphthyl group.

In an exemplary embodiment of the present specification, R1 to R4 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted C 1 to C 20 alkyl group; a substituted or unsubstituted 1 to 20 alkoxy group; a substituted or unsubstituted 6 to 30 aryl group; or a substituted or unsubstituted 6 to 30 heteroaryl group.

In an exemplary embodiment of the present specification, R1 to R4 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted C 1 to C 10 alkyl group; a substituted or unsubstituted 1 to 10 alkoxy group; a substituted or unsubstituted 6 to 20 aryl group; or a substituted or unsubstituted 6 to 20 heteroaryl group.

In an exemplary embodiment of the present specification, R1 to R4 are the same as or different from each other, and are each independently hydrogen.

In an exemplary embodiment of the present specification, Y1 to Y4 are the same as or different from each other, and each independently hydrogen; or one of the following structures, and at least two of Y1 to Y4 are any one of the following structures.

In the above structure, A ₁ to A ₃ are the same as or different from each other, and each independently represents a substituted or unsubstituted C 1 to C 6 alkyl group.

As in the exemplary embodiment of the present specification, in the case of a carbazole derivative including a photocuring group or thermosetting group, an organic light emitting device can be manufactured by a solution coating method, which is economical in time and cost.

In an exemplary embodiment of the present specification, Chemical Formula 2 is represented by any one of the following Chemical Formulas 2-1 to 2-6.

Formula 2-1 Formula 2-2

Formula 2-3 Formula 2-4

Formula 2-5 Formula 2-6

In an exemplary embodiment of the present specification, the ink composition of the present invention includes a solvent represented by Formula 1; And by including the charge transporting material or the light emitting material represented by Formula 2, ink stability can be ensured, and a high boiling point does not cause problems that may occur as the solvent dries, when manufacturing an organic light emitting device A flat film can be formed.

In an exemplary embodiment of the present specification, since the solvent represented by Formula 1 has polarity, solubility in the functional layer material is superior to that of the non-polar solvent. When the film is formed by using the ink composition including the charge transport material or the light emitting material represented by Chemical Formula 2 in the solvent represented by Chemical Formula 1, the drying process time can be shortened, phase separation does not occur, and a uniform film is formed. can be formed

In an exemplary embodiment of the present specification, the boiling point of the solvent represented by Formula 1 may be 180°C or higher, and preferably 200°C or higher and 400°C or lower. When the boiling point of the solvent satisfies the above range, it is possible to prevent the ink from drying in the inkjet nozzle unit, and it is possible to secure ejection stability. It is also advantageous for forming a flat film.

In an exemplary embodiment of the present specification, the charge transporting material or the light emitting material of the ink composition is included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the solvent. When included in the content range, it is easy to obtain a film of a desired thickness by controlling the number of drops. In particular, it is possible to obtain a film having a high thickness, and there is an advantage that a flat film can be formed after drying.

In another exemplary embodiment of the present specification, the charge transporting material or the light emitting material of the ink composition may include 98 parts by weight of the solvent and 2 parts by weight of the charge transporting material or the light emitting material with respect to 100 parts by weight of the ink composition.

In an exemplary embodiment of the present specification, the viscosity of the ink composition is 2 cP or more and 20 cP or less. More preferably, they are 3 cP or more and 15 cP or less. When it has a viscosity in the above range, it can have ejection stability, so it is easy to manufacture the device, and the storage stability of the ink is high, so that the functional layer material does not precipitate during storage.

In an exemplary embodiment of the present specification, the solubility of the charge transport material or the light emitting material with respect to the total weight of the solvent is 1 wt% to 15 wt% at 25 °C and 1 atm. Preferably, the solubility may be 2 wt% to 15 wt% at 25°C and 1 atm based on the total weight of the solvent.

In one embodiment of the present specification, the ink composition may further include one or two compounds selected from the group consisting of a compound and a polymer compound having a crosslinkable functional group introduced into the molecule.

In an exemplary embodiment of the present specification, the ink composition may further include a compound in which a crosslinkable functional group is introduced into a molecule. When the coating composition further includes a compound into which a crosslinkable functional group is introduced into a molecule, the degree of curing of the coating composition may be further increased.

According to an exemplary embodiment of the present specification, the molecular weight of the compound in which a crosslinkable functional group is introduced into the molecule is 100 g/mol to 3,000 g/mol. In another exemplary embodiment of the present specification, the molecular weight of the compound in which a crosslinkable functional group is introduced into the molecule is more preferably 500 g/mol to 2,000 g/mol.

In one embodiment of the present specification, the ink composition may further include a polymer compound. When the ink composition further includes a polymer compound, the ink properties of the ink composition may be improved. That is, the ink composition further comprising the polymer compound can provide a suitable viscosity for coating or inkjet, and can form a flat film.

In an exemplary embodiment of the present specification, the molecular weight of the polymer compound is 10,000 g/mol to 200,000 g/mol.

In one embodiment of the present specification, the polymer compound may further include a photocuring group or a thermosetting group.

In an exemplary embodiment of the present specification, the ink composition may be liquid. The "liquid phase" means a liquid state at room temperature and pressure.

According to an exemplary embodiment of the present specification, when preparing the ink composition, a solvent other than the solvent including the solvent represented by Formula 1, the solvent represented by Formula 2, and the solvent represented by Formula 3 is used as a cosolvent. may include more. For example, ether solvents, such as phenoxytoluene and 3,4- dimethylanisole; ester solvents such as methyl benzoate and dimethyl phthalate; aromatic hydrocarbon solvents such as cyclohexylbenzene, methylnaphthalene, ethylnaphthalene, trimethylbenzene, and mesitylene; aliphatic hydrocarbon solvents such as cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, and n-decane; glycol ether solvents such as diethylene glycol butyl methyl ether and triethylene glycol monobenzyl ether; Although solvents, such as a fluorine-type solvent, are illustrated, these are not limited.

The subsolvent may be included in an amount of 0.1 wt% to 40 wt%, preferably 1 wt% to 30 wt%, based on the total solvent.

In an exemplary embodiment of the present specification, the ink composition may further include one or two or more additives selected from the group consisting of a thermal polymerization initiator and a photopolymerization initiator.

Examples of the thermal polymerization initiator include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, acetylacetone peroxide, methylcyclohexanone peroxide, cyclohexanone peroxide, isobutyryl peroxide, and 2,4-dichlorobenzoyl peroxide. Oxide, bis-3,5,5-trimethyl hexanoyl peroxide, lauryl peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide, dicumylperoxide, 2,5-dimethyl-2,5-(t- Butyl oxy)-hexane, 1,3-bis(t-butyl peroxy-isopropyl) benzene, t-butyl cumyl peroxide, di-tbutyl peroxide, 2,5-dimethyl-2,5- (di-t-butyl peroxy) hexane-3, tris-(t-butyl peroxy) triazine, 1,1-dit-butyl peroxy-3,3,5-trimethyl cyclohexane, 1,1-di t-Butyl peroxycyclohexane, 2,2-di(t-butyl peroxy)butane, 4,4-di-t-butylpaoxyvaleric acid n-butyl ester, 2,2-bis(4 ,4-t-Butyl peroxycyclohexyl)propane, t-butylperoxyisobutylate, dit-butyl peroxyhexahydro terephthalate, t-butyl peroxy-3,5,5-trimethylhexaate, t -Peroxides such as butylperoxybenzoate and dit-butyl peroxytrimethyl adipate, or azo-types such as azobis isobutylnitrile, azobisdimethylvaleronitrile, and azobiscyclohexyl nitrile, but are not limited thereto .

Examples of the photopolymerization initiator include diethoxy acetophenone, 2,2-dimethoxy-1,2-diphenyl ethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 4-(2-hydroxyethoxy) ) Phenyl- (2-hydroxy-2-propyl) ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1,2-hydroxy-2-methyl-1- Phenyl propan-1-one, 2-methyl-2-morpholino (4-methyl thio phenyl) propan-1-one, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) Acetophenone-based or ketal-based photopolymerization initiators such as oxime; Ether type photoinitiator, benzophenone type photoinitiator, such as benzophenone, 4-hydroxybenzophenone, 2-benzoyl naphthalene, 4-benzoyl biphenyl, 4-benzoyl phenyl ether, acrylated benzophenone, 1, 4- benzoylbenzene, etc. ,2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethyl thioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, thioxanthone-based photopolymerization Examples of the initiator and other photopolymerization initiators include ethyl anthraquinone, 2,4,6-trimethylbenzoyl diphenyl phosphine oxide, 2,4,6-trimethylbenzoyl phenyl ethoxy phosphine oxide, bis(2,4,6-trimethylbenzoyl) ) phenyl phosphine oxide, bis (2,4-dimethoxy benzoyl) -2,4,4-trimethyl pentyl phosphine oxide, methyl phenyl glyceryl ester, 9, 10-phenanthrene, acridine-based compound; A triazine-type compound and an imidazole-type compound are mentioned. Moreover, what has a photoinitiator effect can also be used individually or in combination with the said photoinitiator. For example, triethanolamine, methyl diethanol amine, 4-dimethylamino ethyl benzoate, 4-dimethylamino benzoate isoamyl, benzoate (2-dimethylamino) ethyl, 4,4'-dimethylaminobenzophenone, etc., but, It does not limit this.

In one embodiment of the present specification, the ink composition may further include other additives such as surfactants. The surfactant is preferably a nonionic surfactant, and may be a silicone-based or fluorine-based surfactant, but is not limited thereto.

In one embodiment of the present specification, the ink composition does not further include a p-doping material.

In another embodiment, the ink composition further comprises a p-doping material.

In the present specification, the p-doping material may promote thermal curing or photocuring.

In the present specification, the p-doped material refers to a material that allows the host material to have p-semiconductor properties. The p-semiconductor property refers to the property of receiving or transporting holes at the highest occupied molecular orbital (HOMO) energy level, that is, the property of a material having high hole conductivity.

The present specification also provides an organic light emitting device formed using the ink composition.

In one embodiment of the present specification, the cathode; an anode provided to face the cathode; and at least one organic material layer provided between the cathode and the anode, wherein at least one of the organic material layers is formed using the ink composition.

In an exemplary embodiment of the present specification, the organic material layer formed using the ink composition is a hole transport layer, a hole injection layer, or a layer that simultaneously transports holes and injects holes.

In another embodiment, the organic material layer formed using the ink composition is a light emitting layer.

In an exemplary embodiment of the present specification, the organic light emitting device includes a hole injection layer and a hole transport layer. It further includes one or more layers selected from the group consisting of an electron transport layer, an electron injection layer, an electron blocking layer, and a hole blocking layer.

In another exemplary embodiment, the organic light emitting device may be a normal type organic light emitting device in which an anode, one or more organic material layers, and a cathode are sequentially stacked on a substrate.

In another exemplary embodiment, the organic light emitting device may be an inverted type organic light emitting device in which a cathode, one or more organic material layers, and an anode are sequentially stacked on a substrate.

The organic material layer of the organic light emitting device of the present specification may have a single-layer structure, but may have a multi-layer structure in which two or more organic material layers are stacked. For example, the organic light emitting device of the present invention may have a structure including a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, etc. as an organic material layer. However, the structure of the organic light emitting device is not limited thereto and may include a smaller number of organic layers.

For example, the structure of the organic light emitting device according to an exemplary embodiment of the present specification is illustrated in FIG. 1 .

In FIG. 1 , an organic light emitting device in which an anode 201 , a hole injection layer 301 , a hole transport layer 401 , a light emitting layer 501 , an electron transport layer 601 , and a cathode 701 are sequentially stacked on a substrate 101 . structure is illustrated.

1, the hole injection layer 301, the hole transport layer 401, or the light emitting layer 501 is formed using the ink composition.

1 illustrates an organic light emitting device, but is not limited thereto.

When the organic light emitting device includes a plurality of organic material layers, the organic material layers may be formed of the same material or different materials.

The organic light emitting device of the present specification may be manufactured using materials and methods known in the art, except that at least one layer of the organic material layer is formed using the ink composition.

For example, the organic light emitting device of the present specification may be manufactured by sequentially stacking an anode, an organic material layer, and a cathode on a substrate. At this time, by using a PVD (physical vapor deposition) method such as sputtering or e-beam evaporation, a metal or conductive metal oxide or an alloy thereof is deposited on a substrate to form an anode. and forming an organic material layer including a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer thereon, and then depositing a material that can be used as a cathode thereon. In addition to this method, an organic light emitting device may be manufactured by sequentially depositing a cathode material, an organic material layer, and an anode material on a substrate.

The present specification also provides a method of manufacturing an organic light emitting device formed using the ink composition.

Specifically, in one embodiment of the present specification, preparing a substrate; forming a cathode or an anode on the substrate; forming one or more organic material layers on the cathode or anode; and forming an anode or a cathode on the organic material layer, wherein at least one of the organic material layers is formed using the ink composition.

In an exemplary embodiment of the present specification, the organic material layer formed using the ink composition is formed using an inkjet printing method.

In one embodiment of the present specification, the time for heat-treating the organic material layer formed using the ink composition is preferably within 1 hour, more preferably within 30 minutes.

In an exemplary embodiment of the present specification, the atmosphere for heat-treating the organic material layer formed using the ink composition is preferably an inert gas such as argon or nitrogen.

When the step of forming the organic material layer formed using the ink composition includes the heat treatment or light treatment step, a plurality of photocurers or thermosetting groups included in the ink composition form cross-linking to provide an organic material layer including a thinned structure. can In this case, it is possible to prevent dissolution, morphological influence, or decomposition by the solvent deposited on the surface of the organic material layer formed using the ink composition.

Therefore, when the organic material layer formed by using the ink composition is formed including a heat treatment or light treatment step, resistance to solvents increases, so that a multilayer can be formed by repeatedly performing solution deposition and crosslinking methods, and stability of the device is increased Lifespan characteristics can be increased.

In one embodiment of the present specification, the ink composition may be mixed and dispersed in a polymer binder.

In one embodiment of the present specification, as the polymer binder, one that does not extremely inhibit charge transport and does not have strong absorption for visible light is preferably used. Examples of the polymer binder include poly(N-vinylcarbazole), polyaniline and its derivatives, polythiophene and its derivatives, poly(p-phenylenevinylene) and its derivatives, poly(2,5-thienylenevinylene) and Derivatives thereof, polycarbonate, polyacrylate, polymethyl acrylate, polymethyl methacrylate, polystyrene, polyvinyl chloride, polysiloxane and the like are exemplified.

As the anode material, a material having a large work function is generally preferred so that holes can be smoothly injected into the organic material layer. Specific examples of the anode material that can be used in the present invention include metals such as vanadium, chromium, copper, zinc, gold, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); ZnO:Al or SnO ₂ : a combination of a metal such as Sb and an oxide; conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene](PEDOT), polypyrrole, and polyaniline, but are not limited thereto.

The cathode material is preferably a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the cathode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead, or alloys thereof; and a multi-layered material such as LiF/Al or LiO ₂ /Al, but is not limited thereto.

The hole injection layer is a layer for injecting holes from the electrode, and as a hole injection material, it has the ability to transport holes, so it has a hole injection effect at the anode, an excellent hole injection effect on the light emitting layer or the light emitting material, and is produced in the light emitting layer A compound which prevents the movement of excitons to the electron injection layer or the electron injection material and is excellent in the ability to form a thin film is preferable. It is preferable that the highest occupied molecular orbital (HOMO) of the hole injection material is between the work function of the anode material and the HOMO of the surrounding organic material layer. Specific examples of the hole injection material include metal porphyrin, oligothiophene, arylamine-based organic material, hexanitrile hexaazatriphenylene-based organic material, quinacridone-based organic material, and perylene-based organic material. of organic substances, anthraquinones, and conductive polymers of polyaniline and polythiophene series, but are not limited thereto.

The hole transport layer is a layer that receives holes from the hole injection layer and transports the holes to the light emitting layer. material is suitable. Specific examples include, but are not limited to, an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together.

The light emitting material is a material capable of emitting light in the visible ray region by receiving and combining holes and electrons from the hole transport layer and the electron transport layer, respectively, and a material having good quantum efficiency for fluorescence or phosphorescence is preferable. Specific examples include 8-hydroxy-quinoline aluminum complex (Alq ₃ ); carbazole-based compounds; dimerized styryl compounds; BAlq; 10-hydroxybenzo quinoline-metal compounds; compounds of the benzoxazole, benzthiazole and benzimidazole series; Poly(p-phenylenevinylene) (PPV)-based polymers; spiro compounds; polyfluorene, rubrene, and the like, but is not limited thereto.

The emission layer may include a host material and a dopant material. The host material includes a condensed aromatic ring derivative or a heterocyclic compound containing compound. Specifically, condensed aromatic ring derivatives include anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentacene derivatives, phenanthrene compounds, fluoranthene compounds, and the like, and heterocyclic-containing compounds include carbazole derivatives, dibenzofuran derivatives, ladder types. Furan compounds, pyrimidine derivatives, and the like, but are not limited thereto.

Examples of the dopant material include an aromatic amine derivative, a strylamine compound, a boron complex, a fluoranthene compound, and a metal complex. Specifically, the aromatic amine derivative is a condensed aromatic ring derivative having a substituted or unsubstituted arylamino group, and includes pyrene, anthracene, chrysene, periflanthene, and the like, having an arylamino group. As the styrylamine compound, a substituted or unsubstituted It is a compound in which at least one arylvinyl group is substituted in the arylamine, and one or two or more substituents selected from the group consisting of an aryl group, a silyl group, an alkyl group, a cycloalkyl group and an arylamino group are substituted or unsubstituted. Specifically, there are styrylamine, styryldiamine, styryltriamine, styryltetraamine, and the like, but is not limited thereto. In addition, examples of the metal complex include, but are not limited to, an iridium complex and a platinum complex.

The electron transport layer is a layer that receives electrons from the electron injection layer and transports them to the light emitting layer. do. Specific examples include Al complex of 8-hydroxyquinoline; complexes containing Alq ₃ ; organic radical compounds; hydroxyflavone-metal complexes, and the like, but are not limited thereto. The electron transport layer may be used with any desired cathode material as used in accordance with the prior art. In particular, examples of suitable cathode materials are conventional materials having a low work function and followed by a layer of aluminum or silver. Specifically cesium, barium, calcium, ytterbium and samarium, followed in each case by an aluminum layer or a silver layer.

The electron injection layer is a layer that injects electrons from the electrode, has the ability to transport electrons, has an electron injection effect from the cathode, an excellent electron injection effect with respect to the light emitting layer or the light emitting material, and hole injection of excitons generated in the light emitting layer A compound which prevents movement to a layer and is excellent in the ability to form a thin film is preferable. Specifically, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, preorenylidene methane, anthrone, etc., derivatives thereof, metals complex compounds and nitrogen-containing 5-membered ring derivatives, but are not limited thereto.

Examples of the metal complex compound include 8-hydroxyquinolinato lithium, bis(8-hydroxyquinolinato)zinc, bis(8-hydroxyquinolinato)copper, bis(8-hydroxyquinolinato)manganese, Tris(8-hydroxyquinolinato)aluminum, tris(2-methyl-8-hydroxyquinolinato)aluminum, tris(8-hydroxyquinolinato)gallium, bis(10-hydroxybenzo[h] Quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bis (2-methyl-8-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) ( o-crezolato)gallium, bis(2-methyl-8-quinolinato)(1-naphtolato)aluminum, bis(2-methyl-8-quinolinato)(2-naphtolato)gallium, etc. However, the present invention is not limited thereto.

The hole blocking layer is a layer that blocks holes from reaching the cathode, and may be generally formed under the same conditions as the hole injection layer. Specifically, there are oxadiazole derivatives, triazole derivatives, phenanthroline derivatives, BCP, aluminum complex, and the like, but is not limited thereto.

The organic light emitting device according to the present specification may be a top emission type, a back emission type, or a double side emission type depending on the material used.

Hereinafter, examples will be given to describe the present specification in detail. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not to be construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more completely explain the present specification to those of ordinary skill in the art.

Example One.

Based on 100 parts by weight of the ink composition, 2 parts by weight of Formula 2-1 was dissolved in 98 parts by weight of a solvent (ethyl-4-methoxybenzoate) to prepare an ink composition.

Example 2 to 5 and comparative example 1 to 7.

Ink compositions of Examples 2 to 5 and Comparative Examples 1 to 7 were prepared in the same manner as in Example 1, except that the solvents shown in Table 1 were used.

Example 6.

Based on 100 parts by weight of the ink composition, 2 parts by weight of Formula 2-2 was dissolved in 98 parts by weight of a solvent (ethyl-4-methoxybenzoate) to prepare an ink composition.

Example 7 to 10 and comparative example 8 to 12.

Ink compositions of Examples 7 to 10 and Comparative Examples 8 to 12 were prepared in the same manner as in Example 6, except that the solvents shown in Table 2 were used.

Example 11.

Based on 100 parts by weight of the ink composition, 2 parts by weight of Formula 2-3 was dissolved in 98 parts by weight of a solvent (ethyl-4-methoxybenzoate) to prepare an ink composition.

Example 12 to 15 and comparative example 13 to 17.

Ink compositions of Examples 12 to 15 and Comparative Examples 13 to 17 were prepared in the same manner as in Example 11, except that the solvents shown in Table 3 were used.

Example 16.

Based on 100 parts by weight of the ink composition, 2 parts by weight of Formula 2-4 were dissolved in 98 parts by weight of a solvent (ethyl-4-methoxybenzoate) to prepare an ink composition.

Example 17 to 18 and comparative example 18 to 22.

Ink compositions of Examples 17 to 18 and Comparative Examples 18 to 22 were prepared in the same manner as in Example 15, except that the solvents shown in Table 4 were used.

Example 19.

Based on 100 parts by weight of the ink composition, 2 parts by weight of Formula 2-5 were dissolved in 98 parts by weight of a solvent (ethyl-4-methoxybenzoate) to prepare an ink composition.

Example 20 to 22 and comparative example 23 to 26.

Ink compositions of Examples 20 to 22 and Comparative Examples 23 to 26 were prepared in the same manner as in Example 19, except that the solvents shown in Table 5 were used.

Example 23.

Based on 100 parts by weight of the ink composition, 2 parts by weight of Formula 2-6 were dissolved in 98 parts by weight of a solvent (ethyl-4-methoxybenzoate) to prepare an ink composition.

Example 24 to 25 and comparative example 27 to 29.

Ink compositions of Examples 24 to 25 and Comparative Examples 27 to 29 were prepared in the same manner as in Example 23, except that the solvents shown in Table 6 were used.

The solubility, discharge stability, and uniformity of the formed film were measured at 25° C. and 1 atm of the ink compositions prepared in Examples 1 to 25 and Comparative Examples 1 to 29, and are described in Tables 1 to 6 below, and the solubility is poor, so discharge If stability and film uniformity could not be evaluated, “-” was indicated.

1) Solubility evaluation: less than 0.5 wt%: poor

0.5 or more and less than 2.0 wt%: good

2.0 wt% or more: good

2) Ejection stability evaluation: Fujifilm, Dimatix DMP-2800 equipment, 10 pl cartridge (DMC-11610) was used and evaluated according to the following criteria.

All nozzles are discharged without clogging for more than 5 minutes, and droplets are discharged in a straight line without shaking: O.K

Discharge with droplet shaking: N.G

3) Evaluation of film uniformity: After jetting ink on the ITO substrate, vacuum drying was performed to determine whether the film was well formed by using an optical microscope in dark field mode, and evaluation was performed according to the following criteria.

No particle-like foreign matter is observed in the pixel, and film formation is good without phase separation: O.K

A film is not well formed, such as a particle-like foreign body or a shiny dot observed within the pixel: N.G

matter menstruum Solubility ^{One )} Discharge stability ^{2 )} membrane uniformity ^{3 )} Formula 2-1 Example 1 Ethyl 4-methoxybenzoate good O.K. O.K. Example 2 Ethyl 4-ethoxybenzoate good O.K. O.K. Example 3 Ethyl 4-methoxybenzoate + Isoamylbenzoate good O.K. O.K. Example 4 Ethyl 4-methoxybenzoate + ethyl decanoate good O.K. O.K. Example 5 Ethyl 4-methylbenzoate good O.K. O.K. Comparative Example 1 3-Phenoxytoluene good O.K. N.G. Comparative Example 2 Dibenzyl ether good O.K. N.G. Comparative Example 3 Hexyl benzoate good O.K. N.G. Comparative Example 4 Ethyl decanoate Good O.K. N.G. Comparative Example 5 Cyclohexanone good N.G. - Comparative Example 6 Methyl benzoate good N.G. O.K. Comparative Example 7 Ethyl benzoate good N.G. O.K.

matter menstruum Solubility ^{One )} Discharge stability ^{2 )} membrane uniformity ^{3 )} Formula 2-2 Example 6 Ethyl 4-methoxybenzoate good O.K. O.K. Example 7 Ethyl 4-ethoxybenzoate good O.K. O.K. Example 8 Ethyl 4-methoxybenzoate + Isoamylbenzoate good O.K. O.K. Example 9 Ethyl 4-methoxybenzoate + ethyl decanoate good O.K. O.K. Example 10 Ethyl 4-methylbenzoate good O.K. O.K. Comparative Example 8 3-Phenoxytoluene good O.K. N.G. Comparative Example 9 Dibenzyl ether good O.K. N.G. Comparative Example 10 Hexyl benzoate good O.K. N.G. Comparative Example 11 Ethyl decanoate Good O.K. N.G. Comparative Example 12 Cyclohexanone good N.G. -

matter menstruum Solubility ^{One )} Discharge stability ^{2 )} membrane uniformity ^{3 )} Formula 2-3 Example 11 Ethyl 4-methoxybenzoate good O.K. O.K. Example 12 Ethyl 4-ethoxybenzoate good O.K. O.K. Example 13 Ethyl 4-methoxybenzoate + Isoamylbenzoate good O.K. O.K. Example 14 Ethyl 4-methoxybenzoate + ethyl decanoate good O.K. O.K. Example 15 Ethyl 4-methylbenzoate good O.K. O.K. Comparative Example 13 3-Phenoxytoluene bad - - Comparative Example 14 Dibenzyl ether Good O.K. N.G. Comparative Example 15 Hexyl benzoate good O.K. N.G. Comparative Example 16 Ethyl decanoate Good O.K. N.G. Comparative Example 17 Cyclohexanone good N.G. -

matter menstruum Solubility ^{One )} Discharge stability ^{2 )} membrane uniformity ^{3 )} Formula 2-4 Example 16 Ethyl 4-methoxybenzoate good O.K. O.K. Example 17 Ethyl 4-ethoxybenzoate good O.K. O.K. Example 18 Ethyl 4-methoxybenzoate + Isoamylbenzoate good O.K. O.K. Comparative Example 18 3-Phenoxytoluene Good O.K. N.G. Comparative Example 19 Dibenzyl ether Good O.K. N.G. Comparative Example 20 Hexyl benzoate good O.K. N.G. Comparative Example 21 Butyl decanoate Good O.K. N.G. Comparative Example 22 Cyclohexanone good N.G. -

matter menstruum Solubility ^{One )} Discharge stability ^{2 )} membrane uniformity ^{3 )} Formula 2-5 Example 19 Ethyl 4-methoxybenzoate good O.K. O.K. Example 20 Ethyl 4-ethoxybenzoate good O.K. O.K. Example 21 Ethyl 4-methoxybenzoate + Isoamylbenzoate good O.K. O.K. Example 22 Ethyl 4-methylbenzoate good O.K. O.K. Comparative Example 23 3-Phenoxytoluene Good O.K. N.G. Comparative Example 24 Hexyl benzoate good O.K. N.G. Comparative Example 25 Ethyl decanoate Good O.K. N.G. Comparative Example 26 Cyclohexanone good N.G. -

matter menstruum Solubility ^{One )} Discharge stability ^{2 )} membrane uniformity ^{3 )} Formula 2-6 Example 23 Ethyl 4-methoxybenzoate good O.K. O.K. Example 24 Ethyl 4-ethoxybenzoate good O.K. O.K. Example 25 Ethyl 4-methoxybenzoate + Isoamylbenzoate good O.K. O.K. Comparative Example 27 3-Phenoxytoluene Good O.K. N.G. Comparative Example 28 Hexyl benzoate good O.K. N.G. Comparative Example 29 Ethyl decanoate Good O.K. N.G.

From Tables 1 to 6, it can be seen that, compared to the ink compositions prepared in Comparative Examples 1 to 29, the ink compositions prepared in Examples 1 to 25 are generally very excellent in solubility, discharge stability, and film uniformity.

101: substrate
201: anode
301: hole injection layer
401: hole transport layer
501: light emitting layer
601: electron transport layer
701: cathode

Claims (8)

a solvent represented by the following formula (1); And an ink composition comprising a charge transport material or a light emitting material represented by the following formula (2):
[Formula 1]

In Formula 1,
X ₁ To X ₅ Are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted cycloalkenyl group; a substituted or unsubstituted alkoxy group; or a substituted or unsubstituted ester group, and at least one of X ₁ to X ₅ is a substituted or unsubstituted alkyl group; Or a substituted or unsubstituted alkoxy group,
R ₁ is a substituted or unsubstituted alkyl group.
[Formula 2]

In Formula 2,
L1 to L4 are the same as or different from each other, and each independently a substituted or unsubstituted alkylene group; a substituted or unsubstituted cycloalkylene group; a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,
L is a substituted or unsubstituted arylene group; Or a substituted or unsubstituted heteroarylene group,
Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,
R1 to R4 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; a substituted or unsubstituted alkyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,
Y1 to Y4 are the same as or different from each other, and each independently hydrogen; or a photocurer or thermoset, and one of Y1 and Y2 and one of Y3 and Y4 is a photocurer or thermoset,
n1 and n4 are each an integer from 0 to 4,
n2 and n3 are each an integer from 0 to 3,
When each of n1 to n4 is 2 or more, the substituents in parentheses are the same as or different from each other. The method according to claim 1,
The solubility of the charge transporting material or the light emitting material with respect to the total weight of the solvent is 1 wt% to 15 wt% at 25°C and 1 atm. The method according to claim 1,
The ink composition that the boiling point of the solvent is 180 ℃ or more. The method according to claim 1,
The charge transport material or the light emitting material is an ink composition comprising 0.1 parts by weight to 10 parts by weight based on 100 parts by weight of the solvent. The method according to claim 1,
The ink composition has a viscosity of 2 cP or more and 20 cP or less. The method according to claim 1,
In the definition of Y1 to Y4, the photocurable group or the thermosetting group is any one of the following structures:

In the structure,
A ₁ to A ₃ are the same as or different from each other, and each independently represents a substituted or unsubstituted C 1 to C 6 alkyl group. preparing a substrate;
forming a cathode or an anode on the substrate;
forming one or more organic material layers on the cathode or anode; and
Comprising the step of forming an anode or cathode on the organic material layer,
The step of forming the organic material layer is a method of manufacturing an organic light emitting device comprising the step of forming at least one organic material layer using the ink composition of any one of claims 1 to 6. 8. The method of claim 7,
The organic material layer formed by using the ink composition is a method of manufacturing an organic light emitting device is formed by inkjet printing (Inkjet printing) method.

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