Patent Application
20240376327
The present disclosure relates to an ink composition, an organic material layer including the same and an organic light emitting device including the same.
An organic light emission phenomenon is one of the examples of converting an electric current into visible rays through an internal process of a specific organic molecule. The principle of the organic light emission phenomenon is as follows. When an organic material layer is disposed between an anode and a cathode and an electric current is applied between the two electrodes, electrons and holes are injected into the organic material layer from the cathode and the anode, respectively. The electrons and the holes which are injected into the organic material layer are recombined to form an exciton, and the exciton falls down again to the ground state to emit light. An organic light emitting device using the principle may be generally composed of a cathode, an anode, and an organic material layer disposed therebetween, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron injection layer, an electron transport layer, an electron blocking layer, a hole blocking layer, and the like.
In order to manufacture an organic light emitting device in the related art, a deposition process has been usually used. However, there are problems in that the loss of materials occurs frequently when an organic light emitting device is manufactured by a deposition process and in that it is difficult to manufacture a device having a large area, and to solve these problems, a device using a solution process has been developed.
Therefore, there is a need for the development of a material for a solution process.
The present disclosure relates to an ink composition, an organic material layer including the same and an organic light emitting device including the same.
An exemplary embodiment of the present invention provides an ink composition including a compound represented by the following Chemical Formula 1 and a solvent represented by the following Chemical Formula A.
In Chemical Formulae 1 and A,
Another exemplary embodiment of the present invention provides a pixel including an ink composition or a cured product thereof.
Still another exemplary embodiment of the present invention provides an organic material layer including the pixel.
Yet another exemplary embodiment of the present invention provides an organic light emitting device including: a first electrode; a second electrode; and an organic material layer having one or more layers provided between the first electrode and the second electrode, in which one or more layers of the organic material layer include the above-described ink composition or a cured product thereof.
The ink composition according to an exemplary embodiment of the present invention can be used as a material for an organic material layer of an organic light emitting device, and can obtain a device having low driving voltage, excellent light emitting efficiency and long service life characteristics or can be subjected to a solution process, thereby enabling a large area of the device.
An organic material layer including the ink composition according to an exemplary embodiment of the present invention has excellent flatness characteristics.
Hereinafter, the present disclosure will be described in detail.
An exemplary embodiment of the present invention provides an ink composition including a compound represented by the following Chemical Formula 1 and a solvent represented by the following Chemical Formula A.
In Chemical Formulae 1 and A,
Since the compound represented by Chemical Formula 1 according to an exemplary embodiment of the present invention includes two different types of substituents, specifically a haloaryl group and a curable group and includes an amine group including a tricyclic or higher ring to suppress the formation of radicals at the corresponding position, thereby enhancing the stability of the compound and having high highest occupied molecular orbital (HOMO) energy level values and excellent hole mobility. For this reason, when the compound represented by Chemical Formula 1 is included in a hole injection layer in an organic light emitting device, the compound facilitates the injection of holes from the hole injection layer to a hole transport layer, so that an advantage in that it is possible to obtain an organic light emitting device having long service life characteristics significantly affects the improvement of the service life of the device.
As the solvent represented by Chemical Formula A according to an exemplary embodiment of the present invention includes biphenyl as a core structure, the solvent has excellent solubility in an aromatic solute included in the ink composition. In addition, there is an advantage in that the uniformity of an organic material layer can be improved by reducing the thickness deviation according to the position of each pixel due to the good leveling effect. Specifically, the ink composition may reduce the deviation in thickness between pixels coated, dried and heat-treated. Accordingly, it is possible to expect excellent light emitting and/or coloring effects by reducing factors that affect the interference condition of light emitted from the light emitting device according to the thickness.
When one member (layer) is disposed “on” another member (layer) in the present disclosure, this includes not only a case where the one member (layer) is brought into contact with another member, but also a case where still another member (layer) is present between the two members (layers).
When one part “includes” one constituent element in the present disclosure, unless otherwise specifically described, this does not mean that another constituent element is excluded, but means that another constituent element may be further included.
In the present disclosure, the “layer” has a meaning compatible with a “film” usually used in the art, and means a coating covering a target region. The size of the “layer” is not limited, and the sizes of the respective “layers” may be the same as or different from one another. According to an exemplary embodiment, the size of the “layer” may be the same as that of the entire device, may correspond to the size of a specific functional region, and may also be as small as a single sub-pixel.
Unless otherwise defined in the present disclosure, all technical and scientific terms used in the present disclosure have the same meaning as commonly understood by one with ordinary skill in the art to which the present disclosure pertains. Although methods and materials similar to or equivalent to those described in the present disclosure may be used in the practice or in the test of exemplary embodiments of the present invention, suitable methods and materials will be described below. All publications, patent applications, patents, and other references mentioned in the present disclosure are hereby incorporated by reference in their entireties, and in the case of conflict, the present disclosure, including definitions, will control unless a particular passage is mentioned. In addition, the materials, methods, and examples are illustrative only and are not intended to be limiting.
In the present disclosure, the term “combination thereof” included in the Markush type expression means a mixture or combination of one or more selected from the group consisting of constituent elements described in the Markush type expression, and means including one or more selected from the group consisting of the above-described constituent elements.
Examples of the substituents in the present disclosure will be described below, but are not limited thereto.
In the present disclosure,
each mean a moiety to be linked.
In the present disclosure, the term “substitution” means that a hydrogen atom bonded to a carbon atom of a compound is changed into another substituent, and a position to be substituted is not limited as long as the position is a position at which the hydrogen atom is substituted, that is, a position at which the substituent may be substituted, and when two or more substituents are substituted, the two or more substituents may be the same as or different from each other.
In the present disclosure, the term “substituted or unsubstituted” means being substituted with one or more substituents selected from the group consisting of hydrogen; deuterium; a halogen group; an amine group; an alkyl group; an aryl group; and a heteroaryl group, being substituted with a substituent to which two or more substituents among the exemplified substituents are linked, or having no substituent.
In the present disclosure, the fact that two or more substituents are linked indicates that hydrogen of any one substituent is linked to another substituent. For example, an isopropyl group and a phenyl group may be linked to each other to become a substituent of
In the present disclosure, the fact that three substituents are linked to one another may include not only a case where (Substituent 1)-(Substituent 2)-(Substituent 3) are consecutively linked to one another, but also a case where (Substituent 2) and (Substituent 3) are linked to (Substituent 1). For example, two phenyl groups and an isopropyl group may be linked to each other to become a substituent of
The same also applies to the case where four or more substituents are linked to one another.
In the present disclosure, a halogen group is a fluoro group (—F), a chloro group (—Cl), a bromo group (—Br), or an iodo group (—I).
In the present disclosure, an alkyl group may be straight-chained or branched, and the number of carbon atoms thereof is not particularly limited, but is preferably 1 to 30; 1 to 20; 1 to 10; or 1 to 5. Specific examples thereof include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, t-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, t-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, t-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethylpropyl, 1,1-dimethylpropyl, isohexyl, 4-methylhexyl, 5-methylhexyl, and the like, but are not limited thereto. The alkyl group may include a haloalkyl group which is an alkyl group substituted with a halogen group. Specific examples thereof include a methyl group substituted with three fluoro groups, that is, a trifluoromethyl group, and the like, but are not limited thereto.
In the present specification, a cycloalkyl group is not particularly limited, but has preferably 3 to 30 carbon atoms, and specific examples thereof include cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, and the like, but are not limited thereto.
In the present disclosure, an aryl group means a monovalent aromatic hydrocarbon or a monovalent group of an aromatic hydrocarbon derivative. In the present disclosure, an aromatic hydrocarbon means a compound in which pi electrons are completely conjugated and which contains a planar ring, and a group derived from an aromatic hydrocarbon means a structure in which an aromatic hydrocarbon or a cyclic aliphatic hydrocarbon is fused with an aromatic hydrocarbon. Further, in the present disclosure, an aryl group intends to include a monovalent group in which two or more aromatic hydrocarbons or derivatives of an aromatic hydrocarbon are linked to each other. The aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms; 6 to 50 carbon atoms; 6 to 30 carbon atoms; 6 to 25 carbon atoms; 6 to 20 carbon atoms; 6 to 18 carbon atoms; 6 to 15 carbon atoms; 6 to 13 carbon atoms; or 6 to 12 carbon atoms, and may be a monocyclic aryl group or a polycyclic aryl group.
The monocyclic aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms; 6 to 54 carbon atoms; 6 to 48 carbon atoms; 6 to 42 carbon atoms; 6 to 36 carbon atoms; 6 to 30 carbon atoms; 6 to 24 carbon atoms; 6 to 18 carbon atoms; or 6 to 12 carbon atoms, and may be specifically a phenyl group, a biphenyl group, a terphenyl group, and the like, but is not limited thereto.
The polycyclic aryl group is not particularly limited, but preferably has 6 to 60 carbon atoms; 6 to 45 carbon atoms; 6 to 30 carbon atoms; 6 to 22 carbon atoms; 6 to 20 carbon atoms; 6 to 18 carbon atoms; 6 to 16 carbon atoms; 6 to 15 carbon atoms; 6 to 14 carbon atoms; 6 to 13 carbon atoms; 6 to 12 carbon atoms; or 6 to 10 carbon atoms, and may be a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, a triphenylenyl group, a chrysenyl group, a fluorenyl group, and the like, but is not limited thereto.
In the present disclosure, the aryl group may include a haloaryl group substituted with a halogen group. The haloaryl group means an aryl group substituted with one or more halogen groups, and the haloaryl group may be an aryl group substituted with one or more substituents selected from the group consisting of a fluoro group, a chloro group, a bromo group and an iodo group. In addition, the haloaryl group may have the same two halogen groups or more substituted, and may be, for example, not only an aryl group substituted with one fluoro group, but also an aryl group substituted with two or more fluoro groups.
In the present disclosure, a heteroaryl group means a monovalent aromatic hetero ring. Here, the aromatic hetero ring is a monovalent group of an aromatic ring or a derivative of the aromatic ring, and means a group including one or more selected from the group consisting of N, O, P, S, Si and Se as a heteroatom. The derivative of the aromatic ring all includes a structure in which an aromatic ring or an aliphatic ring is fused with an aromatic ring. Further, in the present specification, the heteroaryl group intends to include a monovalent group in which two or more aromatic rings including a heteroatom or two or more derivatives of an aromatic ring including a heteroatom are linked to each other. The number of carbon atoms of the heteroaryl group is preferably 2 to 60; 2 to 50; 2 to 30; 2 to 20; 2 to 18; or 2 to 13. Examples of the heteroaryl group include a thiophene group, a furanyl group, a pyrrole group, an imidazole group, a thiazole group, an oxazole group, a pyridine group, a pyrimidine group, a triazine group, a triazole group, an acridine group, a pyridazine group, a pyrazine group, a quinoline group, a quinazoline group, a quinoxaline group, an isoquinoline group, an indole group, a carbazole group, a benzoxazole group, a benzimidazole group, a benzothiazole group, a benzocarbazole group, a benzothiophene group, a dibenzothiophene group, a benzofuran group, a phenanthrolinyl group, a dibenzofuran group, and the like, but are not limited thereto.
In the present disclosure, the heteroaryl group may be monocyclic or polycyclic, and may be an aromatic ring, an aliphatic ring, or a fused ring of the aromatic ring and the aliphatic ring.
In the present disclosure, the heterocyclic group is a monovalent group of an aliphatic ring, a derivative of the aliphatic ring, an aromatic ring or a derivative of the aromatic ring, and means a group including one or more selected from the group consisting of N, O, P, S, Si and Se as a heteroatom.
In the present disclosure, the aliphatic ring is not an aromatic but a hydrocarbon ring, and examples thereof include examples of the above-described cycloalkyl group, an adamantyl group, and the like.
In the present disclosure, the above-described content on the aryl group may be applied to an aromatic ring.
In the present disclosure, a hydrocarbon ring may be an aromatic ring, an aliphatic ring, or a fused ring of the aromatic ring and the aliphatic ring. Examples of the fused ring of the aromatic ring and the aliphatic ring include a 1,2,3,4-tetrahydronaphthalene group, a 2,3-dihydro-1H-indene group, and the like, but are not limited thereto.
In the present disclosure, the description on the heterocyclic group may be applied to a divalent hetero ring except that the hetero ring is a divalent group.
In the present disclosure, the “adjacent” group may mean a substituent substituted with an atom directly linked to an atom in which the corresponding substituent is substituted, a substituent disposed to be sterically closest to the corresponding substituent, or another substituent substituted with an atom in which the corresponding substituent is substituted. For example, two substituents substituted at the ortho position in a benzene ring and two substituents substituted with the same carbon in an aliphatic ring may be interpreted as “groups which are adjacent” to each other.
In the present disclosure, a curable group may be subjected to polymerization or cross-linking reaction, and through this, a reaction to increase the molecular weight may be performed, and examples of the curable group include a thermosetting group that is cured by heat, a photocurable group that is cured by light, or the like. The curable group is any one selected from the group consisting of the following structures, but is not limited to the following structures.
In the structures,
is a moiety bonded to Chemical Formula 1.
According to an exemplary embodiment of the present invention, Lc1 is a direct bond; a methylene group; or an ethylene group.
According to another exemplary embodiment of the present invention, Lc1 is a direct bond.
According to an exemplary embodiment of the present invention, Rc1 is a methyl group; or an ethyl group.
According to another exemplary embodiment of the present invention, Rc1 is a methyl group.
Hereinafter, the compound represented by Chemical Formula 1 will be specifically described.
According to an exemplary embodiment of the present invention, Chemical Formula 1 is represented by the following Chemical Formula 11.
In Chemical Formula 11,
the definitions of L1 to L3, L11, L12, X1, X2, R1 to R4, Y, Cy1, Cy2, a, b, c, n1 to n4, m1 and m2 are the same as those in Chemical Formula 1.
According to an exemplary embodiment of the present invention, L1 to L3 are the same as or different from each other, and are each independently a direct bond; or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms.
According to another exemplary embodiment, L1 to L3 are the same as or different from each other, and are each independently a direct bond; a substituted or unsubstituted phenylene group; or a substituted or unsubstituted naphthylene group.
According to still another exemplary embodiment, L1 and L2 are each a direct bond.
According to yet another exemplary embodiment, L3 is a direct bond; a substituted or unsubstituted phenylene group; or a substituted or unsubstituted naphthylene group.
According to an exemplary embodiment of the present invention, Chemical Formula 1 is represented by any one of the following Chemical Formulae 12 to 14.
In Chemical Formulae 12 to 14,
According to an exemplary embodiment of the present invention, Y is O, S, CRaRb or SiRcRd.
According to an exemplary embodiment of the present invention, Ra, Rb, Rc and Rd are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group; a substituted or unsubstituted aryl group; or a substituted or unsubstituted heteroaryl group, or are bonded to an adjacent group to form a substituted or unsubstituted ring.
According to another exemplary embodiment, Ra, Rb, Rc and Rd are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms; a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, or are bonded to an adjacent group to form a substituted or unsubstituted ring having 3 to 30 carbon atoms.
According to still another exemplary embodiment, Ra, Rb, Rc and Rd are the same as or different from each other, and are each independently a substituted or unsubstituted methyl group; or a substituted or unsubstituted phenyl group.
According to an exemplary embodiment of the present invention, Cy1 and Cy2 are the same as or different from each other, and are each independently a substituted or unsubstituted benzene ring; or a substituted or unsubstituted naphthalene ring.
In an exemplary embodiment of the present invention, Cy1 and Cy2 are the same as or different from each other, and are each independently any one of the following structures.
In the structures,
According to an exemplary embodiment of the present invention, R11 to R13 are the same as or different from each other, and are each independently hydrogen; deuterium; a halogen group; a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms; a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms; a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.
In another exemplary embodiment, R11 to R13 are each hydrogen.
According to an exemplary embodiment of the present invention, m11 to m13 are each 0 or 1.
According to an exemplary embodiment of the present invention, R1 and R2 are the same as or different from each other, and are each independently hydrogen; deuterium; a halogen group; a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms; a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms; a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.
In still another exemplary embodiment, R1 and R2 are each hydrogen.
According to an exemplary embodiment of the present invention, R3 and R4 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms; a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms; a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.
In yet another exemplary embodiment, R3 and R4 are the same as or different from each other, and are each independently hydrogen; an alkyl group having 1 to 20 carbon atoms; or an aryl group having 6 to 30 carbon atoms.
According to another exemplary embodiment, R3 and R4 are the same as or different from each other, and are each independently hydrogen; a substituted or unsubstituted methyl group; or a substituted or unsubstituted phenyl group.
According to still another exemplary embodiment, R3 and R4 are the same as or different from each other, and are each independently hydrogen; a methyl group; or a phenyl group.
According to an exemplary embodiment of the present invention, n1 and n2 are each independently 0 or 1.
In an exemplary embodiment of the present invention, R21 and R22 are the same as or different from each other, and are each independently hydrogen; deuterium; a halogen group; a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms; a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms; a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.
According to another exemplary embodiment, R21 and R22 are each hydrogen.
According to an exemplary embodiment of the present invention, Chemical Formula 1 may be represented by any one of the following compounds.
For the compound of Chemical Formula 1 according to an exemplary embodiment of the present invention, a core structure may be prepared according to the following Reaction Scheme 1. In addition, each substituent may be bonded by a method known in the art, and the type and position of the substituent or the number of substituents may be changed according to the technology known in the art.
It is preferred that the reaction is carried out as an amine substitution reaction in the presence of a palladium catalyst and a base, and a reactor for the amine substitution reaction can be changed as known in the art.
Hereinafter, a solvent represented by Chemical Formula A will be specifically described.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a hydroxyl group; an ether group; a carbonyl group; an ester group; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted cycloalkenyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryl group; or a substituted or unsubstituted amine group.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a hydroxyl group; a substituted or unsubstituted alkyl group; a substituted or unsubstituted cycloalkyl group; a substituted or unsubstituted cycloalkenyl group; a substituted or unsubstituted alkoxy group; a substituted or unsubstituted aryl group; or a substituted or unsubstituted amine group.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group; or a substituted or unsubstituted alkoxy group.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms; or a substituted or unsubstituted alkoxy group having 1 to 10 carbon atoms.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms; or a substituted or unsubstituted alkoxy group having 1 to 8 carbon atoms.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms; or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; an alkyl group; or an alkoxy group.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a substituted or unsubstituted methyl group; a substituted or unsubstituted ethyl group; a substituted or unsubstituted propyl group; a substituted or unsubstituted butyl group; a substituted or unsubstituted pentyl group; a substituted or unsubstituted hexyl group; a substituted or unsubstituted isopropyl group; a substituted or unsubstituted isobutyl group; a substituted or unsubstituted tert-butyl group; a substituted or unsubstituted methoxy group; a substituted or unsubstituted ethoxy group; a substituted or unsubstituted propoxy group or a substituted or unsubstituted butoxy group.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; a methyl group; an ethyl group; a propyl group; a butyl group; a pentyl group; a hexyl group; an isopropyl group; an isobutyl group; a tert-butyl group; a methoxy group; an ethoxy group; a propoxy group; or a butoxy group.
According to an exemplary embodiment of the present invention, Y1 to Y10 are the same as or different from each other, and are each independently hydrogen; deuterium; an ethyl group; a propyl group; a butyl group; a pentyl group; an isopropyl group; or a methoxy group.
In an exemplary embodiment of the present invention, the solvent represented by Chemical Formula A is any one of the following structures.
In the structures, Y1 to Y10 are the same as or different from each other, and are each independently a substituted or unsubstituted alkyl group; or a substituted or unsubstituted alkoxy group.
According to a preferred exemplary embodiment of the present invention, the solvent represented by Chemical Formula A is any one or a mixed solution of two or more selected from the group consisting of the following compounds.
According to a preferred exemplary embodiment of the present invention, the solvent represented by Chemical Formula A is any one selected from the group consisting of the above compounds.
According to an exemplary embodiment of the present invention, the solvent represented by Chemical Formula A is any one or a mixed solution of two or more selected from the group consisting of 3-isopropylbiphenyl, 3-methoxybiphenyl, 3-ethylbiphenyl, 4-butylbiphenyl and 4-pentylbiphenyl.
According to an exemplary embodiment of the present invention, the solvent represented by Chemical Formula A has a surface tension of 33 mN/m to 37 mN/m; or 33.5 mN/m to 36.5 mN/m.
As the surface tension of the solvent represented by Chemical Formula A according to an exemplary embodiment of the present invention is limited, the range of surface tension between materials other than the solvent represented by Chemical Formula A may be easily adjusted. Specifically, materials (for example, an additional solvent, other organic solvents, and the like) included in the ink composition used in the solution process generally need to be composed of materials, such that the ink composition has a surface tension in a range of 25 mN/m to 45 mN/m, and further, it is preferred that the difference in surface tension between materials is small. A surface tension in a range of 33 mN/m to 37 mN/m is close to the median value of the preferred surface tension range, and accordingly, when the solvent represented by Chemical Formula A has a surface tension in a range of 33 mN/m to 37 mN/m, the difference in surface tension between materials other than the solvent represented by Chemical Formula A may be adjusted so as to be small. When the difference in surface tension between the materials other than the solvent represented by Chemical Formula A is small, the organic light emitting device manufactured by the solution process has an advantage in that the flatness of the organic material layer and the thickness uniformity of the pixel are excellent.
According to an exemplary embodiment of the present invention, the solvent represented by Chemical Formula A has a boiling point of 220° C. to 350° C.; 250° C. to 330° C.; or 265° C. to 315° C.
As the solvent represented by Chemical Formula A having a boiling point within the above range is included, it is possible to expect that when an organic material layer of an organic light emitting device is manufactured through a solution process, the flatness of the organic material layer and/or the thickness uniformity of the pixel are excellent. Specifically, since the solvent represented by Chemical Formula A has the lowest vapor pressure among the constituent solvents, and thus, is not removed in the initial drying step, there is an advantage in that it is possible to adjust the difference in surface tension between materials remaining even after the initial drying step. Consequently, the flatness of the organic material layer and/or the thickness uniformity of the pixel of the organic light emitting device are excellent.
The ink composition according to an exemplary embodiment of the present invention further includes an ionic compound including an anionic group represented by the following Chemical Formula 2.
Hereinafter, an ionic compound including an anionic group represented by the following Chemical Formula 2 will be specifically described.
In Chemical Formula 2,
According to an exemplary embodiment of the present invention, the above-described ink composition further includes an ionic compound including the anionic group represented by Chemical Formula 2. Hereinafter, the compound of Chemical Formula 2 may be expressed as an anionic group compound.
Unlike an ionic compound (hereinafter, referred to as an anionic group compound) including the anionic group represented by Chemical Formula 2 into which a curable group is introduced according to an exemplary embodiment of the present invention, the ionic compound is not cured when the curable group is not introduced, so the properties of the device are reduced due to migration of the ionic compound between electrodes or layers. In addition, when the number of curable groups increases, the curing rate of the ionic compound or the composition including the same increases, and the film retention rate is improved.
In an exemplary embodiment of the present invention, the number of curable groups of the anionic group compound represented by Chemical Formula 2 is 1.
In an exemplary embodiment of the present invention, the number of curable groups of the anionic group compound represented by Chemical Formula 2 is 2.
In an exemplary embodiment of the present invention, the number of curable groups of the anionic group compound represented by Chemical Formula 2 is 4.
In an exemplary embodiment of the present invention, the number of F's; cyano groups; or substituted or unsubstituted fluoroalkyl groups of the anionic group compound represented by Chemical Formula 2 is 16 to 19.
In an exemplary embodiment of the present invention, based on 100 parts by weight of the anionic group compound, the part by weight of F in the anionic group compound is 15 parts by weight to 50 parts by weight.
In an exemplary embodiment of the present invention, based on 100 parts by weight of the anionic group compound, the part by weight of F in the anionic group compound is 10 parts by weight to 45 parts by weight.
In an exemplary embodiment of the present invention, based on 100 parts by weight of the anionic group compound, the number of F's in the anionic group compound is 8 to 20.
As described above, when the ratio of F, the cyano group, or the fluoroalkyl group in the molecule is increased, the film retention rate during heat treatment is improved.
According to an exemplary embodiment of the present invention, the ionic compound may be used in the hole injection layer of the organic light emitting device, and may be used as a dopant when used in the hole injection layer. In this case, when the content of F of the ionic compound is increased, the force of attracting electrons from another compound (host compound) is increased, and holes are more proficiently produced in the host, so that the performance in the hole injection layer is improved.
According to an exemplary embodiment of the present invention, the content of F may be analyzed using COSA AQF-100 combustion furnace coupled to a Dionex ICS 2000 ion-chromatograph, or may be confirmed through 19F NMR which is a method generally used in the F analysis.
In an exemplary embodiment of the present invention, at least one benzene ring of a benzene ring including R201 to R205, a benzene ring including R206 to R210, a benzene ring including R211 to R215, and a benzene ring including R216 to R220 in Chemical Formula 2 is selected from the following structural formulae.
According to an exemplary embodiment of the present invention, Chemical Formula 2 is any one selected from the group consisting of the following compounds.
In the compounds,
Hereinafter, an ionic compound including a cationic group will be specifically described.
According to an exemplary embodiment of the present invention, the above-described ink composition further includes a cationic group. Specifically, the above-described ink composition further includes an ionic compound including the anionic group represented by the above-described Chemical Formula 2 and the cationic group. As another example, the above-described ink composition includes an ionic compound, and the ionic compound includes the anionic group represented by the above-described Chemical Formula 2 and the cationic group.
According to an exemplary embodiment of the present invention, the cationic group is a monovalent cationic group; an onium compound; or any one selected from the following structural formulae.
In the structural formulae,
According to an exemplary embodiment of the present invention, the monovalent cationic group may be an alkali metal cation, and examples of the alkali metal cation include Na+, Li+, K+, and the like, but are not limited thereto.
According to an exemplary embodiment of the present invention, the cationic group is an onium compound; or any one selected from the above-described structural formulae.
According to an exemplary embodiment of the present invention, the cationic group is represented by any one of the following Chemical Formulae 310 to 315.
In Chemical Formulae 310 to 315,
According to an exemplary embodiment of the present invention, the cationic group is any one selected from the following structural formulae.
According to an exemplary embodiment of the present invention, the ionic compound is any one selected from the group consisting of the following chemical formulae.
Hereinafter, an ink composition will be specifically described.
An exemplary embodiment of the present invention provides an ink composition including the above-described compound represented by Chemical Formula 1 and the above-described solvent represented by Chemical Formula A.
According to an exemplary embodiment of the present invention, the ink composition further includes an ionic compound including the anionic group represented by the above-described Chemical Formula 2.
According to an exemplary embodiment of the present invention, the ionic compound further includes the above-described cationic group compound. That is, the ink composition further includes an ionic compound including the anionic group represented by the above-described Chemical Formula 2 and the above-described cationic group.
According to a preferred exemplary embodiment of the present invention, the ink composition further includes one or more additional solvents of tetralin, 4-methoxytoluene, tetrahydrofuran, dioxane, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, a solvent represented by the following Chemical Formula C-1 or a solvent represented by the following Chemical Formula C-2.
In Chemical Formulae C-1 and C-2,
According to an exemplary embodiment of the present specification, the additional solvent is one or more selected from the group consisting of tetralin, 4-methoxytoluene, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, the solvent represented by Chemical Formula C-1 and the solvent represented by Chemical Formula C-2.
According to an exemplary embodiment of the present invention, the additional solvent has a viscosity of 1 cP to 15 cP.
As an additional solvent having a viscosity within the above range is included, there is an advantage in that an ink composition having a viscosity suitable for an inkjet printing process can be prepared.
According to an exemplary embodiment of the present invention, the additional solvent has a boiling point lower than that of the solvent represented by Chemical Formula A.
According to an exemplary embodiment of the present invention, the additional solvent has a boiling point of 70° C. to 280° C.; 100° C. to 280° C.; 180° C. to 280° C.; 180° C. to 265° C.; or 190° C. to 250° C.
As the additional solvent having a boiling point within the above range is included, there is an advantage in that an ink composition having a drying rate suitable for an inkjet printing process can be prepared.
According to an exemplary embodiment of the present invention, the solvent represented by Chemical Formula C-1 is any one selected from the group consisting of the following structures.
According to an exemplary embodiment of the present invention, the solvent represented by Chemical Formula C-2 is benzyl butyrate.
According to an exemplary embodiment of the present invention, one or two of the solvents of the above-described examples are used as the additional solvent.
According to an exemplary embodiment of the present invention, the ink composition includes a first additional solvent selected from the group consisting of tetralin, 4-methoxytoluene, tetrahydrofuran, dioxane, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, the solvent represented by Chemical Formula C-1 and the solvent represented by Chemical Formula C-2.
According to an exemplary embodiment of the present invention, the ink composition includes a first additional solvent and a second additional solvent selected from the group consisting of tetralin, 4-methoxytoluene, tetrahydrofuran, dioxane, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, the solvent represented by Chemical Formula C-1 and the solvent represented by Chemical Formula C-2, and the first additional solvent and the second additional solvent are different from each other.
According to an exemplary embodiment of the present invention, the ink composition includes a first additional solvent selected from the group consisting of the solvent represented by Chemical Formula C-1 and the solvent represented by Chemical Formula C-2.
According to an exemplary embodiment of the present invention, the ink composition includes a second additional solvent selected from the group consisting of tetralin, 4-methoxytoluene, tetrahydrofuran, dioxane, dipropylene glycol monomethyl ether and tripropylene glycol monomethyl ether.
An exemplary embodiment of the present invention provides an ink composition including: the compound represented by the above-described Chemical Formula 1; the solvent represented by the above-described Chemical Formula A; the ionic compound including the anionic group represented by the above-described Chemical Formula 2; and the above-described additional solvent.
An exemplary embodiment of the present invention provides an ink composition including: the compound represented by the above-described Chemical Formula 1; the solvent represented by the above-described Chemical Formula A; the above-described ionic compound; and the above-described additional solvent, and the ionic compound includes the anionic group represented by the described-above Chemical Formula 2 and the above-described cationic group.
According to an exemplary embodiment of the present invention, based on 100 wt % of the ink composition, the compound represented by Chemical Formula 1 is included in an amount of 0.1 wt % to 15 wt %; 0.1 wt % to 10 wt %; or 0.1 wt % to 5 wt %.
According to an exemplary embodiment of the present invention, based on 100 wt % of the ink composition, the solvent represented by Chemical Formula A is included in an amount of 1 wt % to 70 wt %; 1 wt % to 50 wt %; or 1 wt % to 30 wt %.
According to an exemplary embodiment of the present invention, based on 100 wt % of the ink composition, the ionic compound including the anionic group represented by Chemical Formula 2 is included in an amount of 0.1 wt % to 15 wt %; 0.1 wt % to 10 wt %; or 0.1 wt % to 5 wt %.
According to an exemplary embodiment of the present invention, based on 100 wt % of the ink composition, the additional solvent is included in an amount of 10 wt % to 90 wt %; 10 wt % to 85 wt %; 10 wt % to 80 wt %; or 10 wt % to 70 wt %. However, the amount is not limited to the above examples, and an amount typically used by those skilled in the art to which the present disclosure pertains may be used as the content of the additional solvent.
According to an exemplary embodiment of the present invention, based on 100 wt % of the ink composition, the compound represented by Chemical Formula 1 is included in an amount of 0.1 wt % to 15 wt %; the solvent represented by Chemical Formula A is included in an amount of 1 wt % to 70 wt %; the ionic compound including the anionic group represented by Chemical Formula 2 is included in an amount of 0.1 wt % to 15 wt; and the additional solvent is included in an amount of 10 wt % to 85 wt %.
According to an exemplary embodiment of the present invention, the ink composition has a viscosity of 2 cP to 15 cP at room temperature. When the above viscosity is satisfied, a device is easily manufactured. Specifically, a uniform film may be formed when an organic material layer in an organic light emitting device is formed.
The above viscosity is a value measured at room temperature using a viscometer manufactured by Brookfield Engineering Labs Inc. after dissolving an object to be measured at any one concentration of 1 wt % to 3 wt % in a solvent. In this case, the object to be measured is a compound represented by Chemical Formula 1; or a mixture of the compound represented by Chemical Formula 1 and the above-described ionic compound. Further, the solvent is a solvent represented by Chemical Formula A; or a mixed solvent of a solvent represented by Chemical Formula A and an additional solvent.
According to an exemplary embodiment of the present invention, the ink composition is a liquid phase. The “liquid phase” means that the composition is in a liquid state at room temperature under atmospheric pressure.
In an exemplary embodiment of the present specification, the ink composition can be cured by a heat treatment or a light treatment. When the ink composition is cured, this may be expressed as a cured product of the ink composition.
According to an exemplary embodiment of the present invention, the ink composition further includes: a single molecule including a photocurable group and/or a thermosetting group; or a single molecule including an end group capable of forming a polymer by heat. As described above, the single molecule including a photocurable group and/or a thermosetting group; or the single molecule including an end group capable of forming a polymer by heat may be a compound having a molecular weight of 3,000 g/mol or less, but the molecular weight is not limited to the exemplified molecular weight.
The single molecule including a photocurable group and/or a thermosetting group; or the single molecule including an end group capable of forming a polymer by heat may mean aryl such as phenyl, biphenyl, fluorene, and naphthalene; arylamine; or a single molecule in which a fluorene is substituted with photocurable group and/or a thermosetting group or an end group capable of forming a polymer by heat.
According to an exemplary embodiment of the present invention, the ink composition may further include another additional solvent (hereinafter, expressed as a third solvent) other than the above-described additional solvent. The third solvent may be one or more selected from the group consisting of a chlorine-based solvent such as chloroform, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, and o-dichlorobenzene; an ether-based solvent such as tetrahydrofuran, dioxane, and dipropylene glycol monomethyl ether; an aromatic hydrocarbon-based solvent such as toluene, xylene, trimethylbenzene, and mesitylene; an aliphatic hydrocarbon-based solvent such as cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, and n-decane; a ketone-based solvent such as acetone, methyl ethyl ketone, cyclohexanone, isophorone, tetralone, decalone, and acetylacetone; an ester-based solvent such as ethyl acetate, butyl acetate, ethyl cellosolve acetate, and benzyl butyrate; a polyhydric alcohol such as ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, dimethoxy ethane, propylene glycol, diethoxymethane, triethylene glycol monoethyl ether, glycerin, and 1,2-hexanediol, and derivatives thereof; an alcohol-based solvent such as methanol, ethanol, propanol, isopropanol, and cyclohexanol; a sulfoxide-based solvent such as dimethyl sulfoxide; an amide-based solvent such as N-methyl-2-pyrrolidone and N,N-dimethylformamide; and tetralin. However, the third solvent is not limited to the above example, and is sufficient as long as the third solvent can dissolve or disperse the compound represented by the above-described Chemical Formula 1.
According to an exemplary embodiment of the present invention, the ink composition is a composition for forming one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, and an electron blocking layer.
Hereinafter, a pixel including the above-described ink composition or a curred product thereof will be specifically described.
An exemplary embodiment of the present invention provides a pixel including an ink composition or a cured product thereof. The pixel may be included in an organic material layer, an organic light emitting diode, or an organic light emitting display device. Details of the organic material layer will be described below. Specifically, the organic light emitting display device includes a plurality of pixels composed of red (R), green (G), and blue (B) sub-pixels, and an organic light emitting diode (OLED) and a pixel circuit are located for each sub-pixel. An organic light emitting diode includes two electrodes (anode and cathode) and an organic light emitting layer located therebetween, and a pixel circuit includes at least two thin film transistors and at least one capacitor. The organic material layer, the organic light emitting diode, or the organic light emitting display device may include a bank. Preferably, the organic material layer, the organic light emitting diode, or the organic light emitting display device may include a line-shaped bank. The line-shaped bank may define a line-shaped pixel region and/or a sub-pixel region. In a normal case, the light emitting layer among the organic material layers is composed of a red light emitting layer, a green light emitting layer and a blue light emitting layer located in a red sub-pixel, a green sub-pixel and a blue sub-pixel, respectively. In this case, the above-described pixel may correspond to the pixel or sub-pixel. As a preferred exemplary embodiment, the pixel corresponds to the sub-pixel.
According to an exemplary embodiment of the present invention, one or more of the pixels may be included in the above-described organic material layer, organic light emitting diode or organic light emitting display device.
According to an exemplary embodiment of the present invention, the thickness uniformity V of the one or more pixels is 0.4 or less, and the thickness uniformity V satisfies the following Equation 1.
According to an exemplary embodiment of the present invention, the thickness uniformity V satisfies the following Equation 1.
In Equation 1,
In the present disclosure, when the thickness uniformity V is 0.4 or lower and the thickness uniformity V satisfies Equation 1, it means that the thickness uniformity V calculated using Equation 1 is 0.4 or lower.
According to an exemplary embodiment of the present invention, the thickness uniformity is 0.01 to 0.4, or 0.02 to 0.4.
In the present disclosure, a low thickness uniformity value means that the thicknesses of the pixels are uniformly formed. That is, it means that the lower the thickness uniformity value, the more uniformly the pixels are formed.
According to an exemplary embodiment of the present invention, the thickness of the pixel may mean the thickness of the central portion of the pixel, and may be measured by an optical thickness measuring device. As the optical thickness measuring device, an optical profiler manufactured by Bruker or the like may be used, but the optical thickness measuring device is not limited thereto.
An exemplary embodiment of the present invention provides an organic material layer including the above-described pixel. That is, an exemplary embodiment of the present invention provides an organic material layer including the above-described ink composition or a cured product thereof.
Hereinafter, an organic material layer including the above-described pixel will be specifically described.
According to an exemplary embodiment of the present invention, the organic material layer includes a plurality of the pixels. For example, the organic material layer includes an x-axis on which na pixels are aligned and a y-axis that is perpendicular to the x-axis and on which nb pixels are aligned, and na and nb are each an integer from 2 to 104.
According to an exemplary embodiment of the present invention, na and nb are each 2 or higher; 5 or higher; 10 or higher; 20 or higher; or 40 or higher, 104 or lower; 103 or lower; or 102 or lower.
According to an exemplary embodiment of the present invention, the organic material layer includes 2 or more; 4 or more; 10 or more; 20 or more; 40 or more; 80 or more; or 100 or more and 108 or less; 106 or less; 104 or less; or 103 or less pixels.
According to an exemplary embodiment of the present invention, pixels included in the organic material layer are aligned in the form of a line. For example, as shown in
According to an exemplary embodiment of the present invention, the organic material layer includes a plurality of lines in which the plurality of pixels are aligned in a row. For example, as shown in
According to an exemplary embodiment of the present invention, the organic material layer includes na×nb pixels.
According to an exemplary embodiment of the present invention, a plurality of pixels included in the organic material layer have a uniform thickness.
According to an exemplary embodiment of the present invention, the organic material layer includes n′ pixels, the thickness uniformity V of the n′ pixels is 0.4 or lower, and the thickness uniformity V satisfies the above-described Equation 1.
According to an exemplary embodiment of the present invention, n′ is 2 to 104.
According to an exemplary embodiment of the present invention, the organic material layer is included in an organic light emitting device.
According to an exemplary embodiment of the present invention, the organic material layer is formed by a solution process.
According to an exemplary embodiment of the present invention, the organic material layer is one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron injection layer, an electron transport layer, and an electron injection and transport layer.
According to an exemplary embodiment of the present invention, the organic material layer is one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, an electron blocking layer, and a light emitting layer.
According to an exemplary embodiment of the present invention, the organic material layer is one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, and an electron blocking layer.
According to an exemplary embodiment of the present invention, the ink composition is a composition for forming one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, and an electron blocking layer.
According to a preferred exemplary embodiment of the present invention, the organic material layer is a hole injection layer, a hole transport layer or an electron blocking layer.
Hereinafter, an organic light emitting device will be specifically described.
An exemplary embodiment of the present invention provides an organic light emitting device including: a first electrode; a second electrode; and an organic material layer having one or more layers provided between the first electrode and the second electrode, in which one or more layers of the organic material layer include the above-described ink composition or a cured product thereof.
According to an exemplary embodiment of the present invention, the organic material layer includes one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron injection layer, an electron transport layer, and an electron injection and transport layer, and the one or more layers selected from the group consisting of the hole injection layer, the hole transport layer, the hole injection and transport layer, the electron blocking layer, the light emitting layer, the hole blocking layer, the electron injection layer, the electron transport layer, and the electron injection and transport layer include the ink composition or a cured product thereof.
According to an exemplary embodiment of the present invention, the organic material layer includes one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole injection and transport layer, and an electron blocking layer, and the one or more layers selected from the group consisting of the hole injection layer, the hole transport layer, the hole injection and transport layer, and the electron blocking layer include the ink composition or a cured product thereof.
According to a preferred exemplary embodiment of the present invention, the organic material layer includes a hole injection layer, a hole transport layer, or an electron blocking layer, and the hole injection layer, the hole transport layer, or the electron blocking layer includes the ink composition or a cured product thereof.
According to an exemplary embodiment of the present invention, the organic material layer included in the organic light emitting device includes n′ of the above-described pixels, the thickness uniformity V of the n′ pixels is 0.4 or lower, and the thickness uniformity V satisfies the above-described Equation 1.
Hereinafter, a method for manufacturing an organic light emitting device will be specifically described.
An exemplary embodiment of the present invention provides a method for manufacturing an organic light emitting device, the method including: preparing a first electrode;
According to an exemplary embodiment of the present invention, the forming of the organic material layer using the ink composition may form the organic material layer on a substrate including a line-shaped bank or an organic material layer.
As an example, the above-described ink composition is applied (
According to another exemplary embodiment of the present invention, the forming of the organic material layer using the ink composition uses a spin coating method.
According to still another exemplary embodiment of the present invention, the forming of the organic material layer using the ink composition uses a printing method.
According to an exemplary embodiment of the present invention, examples of the printing method include inkjet printing, nozzle printing, offset printing, transfer printing, screen printing, or the like, but are not limited to the printing methods listed above.
According to an exemplary embodiment of the present invention, the forming of the organic material layer using the ink composition uses an inkjet printing method.
A solution process is suitable for the ink composition according to an exemplary embodiment of the present invention due to the composition and structural characteristics of materials included, so that the organic material layer may be formed by a printing method, and as a result, there is an economic effect in terms of time and costs when a device is manufactured.
According to an exemplary embodiment of the present invention, the forming of the organic material layer on the first electrode may further include drying after one or more steps of pressure reduction. As an example, the forming of the organic material layer on the first electrode further includes drying after two steps of pressure reduction. In this case, the drying after the first pressure reduction is performed under normal pressure to 2×10−2 torr, and the pressure reduction time under normal pressure to 2×10−2 torr may be 30 seconds to 600 seconds. Further, the drying after the second pressure reduction is performed under 2×10−2 to 2×10−6 torr, and the pressure reduction time under 2×10−2 torr to 2×10−6 torr may also be 30 seconds to 600 seconds.
According to an exemplary embodiment of the present invention, the forming of the organic material layer using the ink composition includes: coating the ink composition; and heat-treating or light-treating the coated ink composition.
According to an exemplary embodiment of the present invention, the forming of the organic material layer using the ink composition includes: coating the first electrode or the organic material layer having one or more layers with the ink composition; and heat-treating or light-treating the coated ink composition.
According to an exemplary embodiment of the present invention, the heat-treating of the ink composition may be performed through a heat treatment, and the heat treatment temperature in the heat-treating of the ink composition may be 85° C. to 250° C., may be 100° C. to 250° C. according to an exemplary embodiment, and may be 150° C. to 250° C. in another exemplary embodiment.
According to an exemplary embodiment of the present invention, the heat treatment time in the heat-treating of the ink composition may be in a range of 10 minutes to 2 hours, may be in a range of 10 minutes to 1 hour according to an exemplary embodiment, and may be in a range of 20 minutes to 1 hour in another exemplary embodiment.
When the forming of the organic material layer using the ink composition includes the heat-treating or light-treating of the ink composition, a plurality of the compounds included in the ink composition may form a cross-linkage, thereby providing an organic material layer including a thin-filmed structure. In this case, it is possible to prevent the organic material layer from being dissolved, morphologically affected or decomposed by a solvent when another layer is stacked on the surface of the organic material layer formed using the ink composition.
Therefore, when the organic material layer formed using the ink composition is formed by a method including the subjecting of the organic material layer to the heat treatment or the light treatment, resistance to a solvent is increased, so that a plurality of layers may be formed by repeatedly carrying out solution deposition and cross-linking methods, and stability is increased, so that service life characteristics of the device may be increased.
Hereinafter, the types of organic material layers included in the above-described organic light emitting device will be specifically described.
According to an exemplary embodiment of the present invention, the organic light emitting device includes an organic material layer having one layer, and the organic material layer includes the above-described ink composition or a cured product thereof.
According to another exemplary embodiment of the present invention, the organic light emitting device includes an organic material layer having two or more layers, and the organic material layer having two or more layers includes the above-described ink composition or a cured product thereof. For example, among organic material layers having two or more layers, the organic material layer having any one layer includes the ink composition or a cured product thereof, and further includes the organic material layer having the other layer or more. The organic material layer having the other layer or more according to an exemplary embodiment does not include the ink composition or a cured product thereof. The organic material layer having the other layer or more according to another exemplary embodiment further includes the ink composition or a cured product thereof. However, the organic material layer having the other layer or more is not limited to the examples.
The organic material layer having two or more layers includes two or more layers selected from the group consisting of, for example, a hole injection layer, a hole transport layer, a hole injection and transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, an electron injection and transport layer, and the like. In this case, the hole injection and transport layer means a layer which simultaneously injects and transports holes, and the electron injection and transport layer means a layer which simultaneously injects and transports electrons. However, the organic material layers forming the group are merely an example, and are not limited to the above example. Further, the organic material layer having two or more layers may include two or more layers that play the same role, if necessary. The organic light emitting device according to an exemplary embodiment includes a first hole injection layer and a second hole injection layer. However, the organic material layer having two or more layers is not limited to the examples.
According to an exemplary embodiment of the present invention, the organic material layer includes a light emitting layer. As an example, the light emitting layer includes the ink composition or a cured product thereof. As a specific example, the light emitting layer includes the ink composition or a cured product thereof as a host of the light emitting layer. As another specific example, the light emitting layer includes the ink composition or a cured product thereof as a dopant of the light emitting layer.
According to an exemplary embodiment of the present invention, the organic material layer includes a hole injection and transport layer, a hole injection layer, a hole transport layer and an electron blocking layer. As an example, the hole injection and transport layer, the hole injection layer, the hole transport layer or the electron blocking layer includes an ink composition or a cured product thereof.
According to a preferred exemplary embodiment of the present invention, the organic material layer includes a hole transport layer or an electron blocking layer. As an example, the hole transport layer or the electron blocking layer includes the ink composition or a cured product thereof.
According to a preferred exemplary embodiment of the present invention, the organic material layer includes a hole injection layer and a hole transport layer.
According to an exemplary embodiment of the present invention, the organic material layer further includes one or more layers selected from the group consisting of a hole blocking layer, an electron transport layer, an electron injection layer, and an electron injection and transport layer. As an example, one or more layers selected from the group consisting of the hole blocking layer, the electron transport layer, the electron injection layer, and the electron injection and transport layer include the ink composition or a cured product thereof. As another example, one or more layers selected from the group consisting of the hole blocking layer, the electron transport layer, the electron injection layer, and the electron injection and transport layer do not include an ink composition or a cured product thereof.
An exemplary embodiment of the present invention provides an organic light emitting device including: a first electrode; a second electrode; and an organic material layer having one or more layers provided between the first electrode and the second electrode, in which the organic material layer includes a light emitting layer and a hole injection layer, and the hole injection layer includes the ink composition or a cured product thereof.
Hereinafter, the stacking structure of the organic material layer and the organic light emitting device including the organic material layer will be specifically described.
The organic material layer of the organic light emitting device according to an exemplary embodiment of the present invention has a single-layered structure. For example, the organic material layer having the single-layered structure is provided between the first electrode and the second electrode of the organic light emitting device, and includes the ink composition or a cured product thereof. According to a specific exemplary embodiment, the organic material layer having the single-layered structure is a light emitting layer, and in this case, the light emitting layer includes the ink composition or a cured product thereof.
The organic material layer of the organic light emitting device according to another exemplary embodiment of the present invention has a multi-layered structure in which an organic material layer having two or more layers is stacked. For example, the organic material layer having the multi-layered structure is provided between the first electrode and the second electrode of the organic light emitting device.
According to an exemplary embodiment of the present invention, the organic material layer having the multi-layered structure includes a light emitting layer and an organic material layer other than the light emitting layer. As an example, the light emitting layer is provided between the first electrode and the second electrode, and the organic material layer other than the light emitting layer is provided between the first electrode and the light emitting layer. As another example, the light emitting layer is provided between the first electrode and the second electrode, and the organic material layer other than the light emitting layer is provided between the light emitting layer and the second electrode. As still another example, the light emitting layer is provided between the first electrode and the second electrode, any one organic material layer other than the light emitting layer is provided between the first electrode and the light emitting layer, and the other organic material layer other than the light emitting layer is provided between the light emitting layer and the second electrode. However, the above structure is merely an example, and the structure is not limited to the above structure. Further, the organic material layer other than the light emitting layer may be one or more layers selected from the group consisting of, for example, a hole injection and transport layer, a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, an electron injection layer, an electron injection and transport layer, and the like, but is not limited thereto.
In general, a hole injection layer, a hole transport layer or an electron blocking layer in an organic light emitting device is provided between an anode and a light emitting layer. As a specific example, the hole injection layer is provided on the anode, the hole transport layer is provided on the hole injection layer, and the electron blocking layer is provided on the hole injection layer, but the present disclosure is not limited to the above examples.
Further, in general, an electron injection layer, an electron transport layer or a hole blocking layer in an organic light emitting device is provided between a cathode and a light emitting layer. As a specific example, the hole blocking layer is provided on the light emitting layer, the electron transport layer is provided on the hole blocking layer, and the electron injection layer is provided on the electron transport layer, but the present disclosure is not limited to the above examples.
The organic material layer having a multi-layered structure included in the organic light emitting device according to an exemplary embodiment of the present invention includes: one or more layers selected from the group consisting of a hole injection and transport layer, a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, an electron injection layer, and an electron injection and transport layer; and a light emitting layer, the light emitting layer is provided between a first electrode and a second electrode, the one or more layers are provided between the first electrode and the light emitting layer or between the second electrode and the light emitting layer, and the one or more layers include an ink composition or a cured product thereof.
The structure of the organic light emitting device according to an exemplary embodiment of the present invention is illustrated in
As described above, an organic light emitting device having an organic material layer having a single-layered or multi-layered structure may have, for example, the following stacking structure, but the stacking structure is not limited thereto.
In the structures, the ‘Electron transport layer/Electron injection layer’ may be replaced with an ‘electron injection and transport layer’ or a ‘layer that simultaneously injects and transports electrons’.
Further, in the structures, the ‘Hole injection layer/Hole transport layer’ may be replaced with the ‘hole injection and transport layer’ or the “layer which simultaneously injects and transports holes”.
According to an exemplary embodiment of the present invention, the first electrode is an anode, and the second electrode is a cathode.
According to another exemplary embodiment of the present invention, the first electrode is a cathode, and the second electrode is an anode.
According to an exemplary embodiment of the present invention, the organic light emitting device may be a normal type organic light emitting device in which an anode, an organic material layer having one or more layers, and a cathode are sequentially stacked on a substrate.
According to another exemplary embodiment of the present invention, the organic light emitting device may be an inverted type organic light emitting device in which a cathode, an organic material layer having one or more layers, and an anode are sequentially stacked on a substrate.
Hereinafter, the specific content of the above-described organic material layer, a material thereof, and a manufacturing method thereof will be described. However, the organic light emitting device of the present disclosure may be manufactured by materials and methods known in the art, except that the organic material layer includes the above-described compound.
In an organic light emitting device according to an exemplary embodiment of the present invention, one or more layers of the organic material layer are formed using the ink composition or a cured product thereof. Except for this, the organic light emitting device may be manufactured by materials and methods known in the art.
For example, the organic light emitting device of the present disclosure may be manufactured by sequentially stacking an anode, an organic material layer, and a cathode on a substrate. In this case, the organic light emitting device may be manufactured by depositing a metal or a metal oxide having conductivity, or an alloy thereof on a substrate to form an anode, forming an organic material layer including one or more layers of a hole injection layer, a hole transport layer, a light emitting layer, an electron injection layer, an electron transport layer, a hole transport and injection layer, and an electron injection and transport layer thereon through a solution process, a deposition process, the like, and then depositing a material, which may be used as a cathode, thereon, by using a physical vapor deposition (PVD) method such as sputtering or e-beam evaporation. In addition to the method described above, an organic light emitting device may be made by sequentially depositing a cathode material, an organic material layer, and an anode material on a substrate.
As the anode material, materials having a high work function are usually preferred so as to facilitate the injection of holes into an organic material layer. Examples thereof include: a metal, such as vanadium, chromium, copper, zinc, and gold, or an alloy thereof; a metal oxide, such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); a combination of a metal and an oxide, such as ZnO:Al or SnO2:Sb; a conductive polymer, such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole, and polyaniline; and the like, but are not limited thereto.
As the cathode material, materials having a low work function are usually preferred so as to facilitate the injection of electrons into an organic material layer. Examples thereof include: a metal, such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or an alloy thereof; a multi-layer structured material, such as LiF/Al or LiO2/Al; and the like, but are not limited thereto.
The light emitting layer may include a host material and/or a dopant material.
Examples of the host material include a fused aromatic ring derivative, a hetero ring-containing compound, or the like. Specific examples of the fused aromatic ring derivative include anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentacene derivatives, phenanthrene compounds, fluoranthene compounds, and the like, and specific examples of the hetero ring-containing compound include dibenzofuran derivatives, ladder-type furan compounds, pyrimidine derivatives, and the like, but the examples are not limited thereto.
Examples of the dopant material include an aromatic amine derivative, a styrylamine compound, a boron complex, a fluoranthene compound, a metal complex, and the like. Specifically, the aromatic amine derivative is a fused aromatic ring derivative having a substituted or unsubstituted arylamine group, and examples thereof include pyrene, anthracene, chrysene, periflanthene, and the like having an arylamine group. Further, the styrylamine compound is a compound in which a substituted or unsubstituted arylamine is substituted with at least one arylvinyl group, 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 arylamine group are substituted or unsubstituted. Specific examples thereof include styrylamine, styryldiamine, styryltriamine, styryltetramine, and the like, but are not limited thereto. Further, examples of the metal complex include an iridium complex, a platinum complex, and the like, but are not limited thereto.
The hole injection layer is a layer which accepts holes from an electrode. It is preferred that hole injection material has an ability to transport holes, and has an effect of accepting holes from an anode and an excellent hole injection effect for a light emitting layer or a light emitting material. Further, the hole injection material is preferably a material which is excellent in ability to prevent excitons produced from a light emitting layer from moving to an electron injection layer or an electron injection material. In addition, the hole injection material is preferably a material which is excellent in ability to form a thin film. In addition, the HOMO of the hole injection material is preferably a value between the work function of the anode material and the HOMO of the neighboring organic material layer. Specific examples of the hole injection material include: metal porphyrin, oligothiophene, and arylamine-based organic materials; hexanitrile hexaazatriphenylene-based organic materials; quinacridone-based organic materials; perylene-based organic materials; polythiophene-based conductive polymers such as anthraquinone and polyaniline; and the like, but are not limited thereto.
The hole transport layer is a layer which accepts holes from a hole injection layer and transports the holes to a light emitting layer, and may have a single-layered structure or a multi-layered structure having two or more layers. A hole transport material is preferably a material having high hole mobility which may accept holes from an anode or a hole injection layer and transfer the holes to a light emitting layer. In the present disclosure, the compound represented by the above-described Chemical Formula 1 may be included as a hole transport material. Furthermore, it is possible to further include other hole transport materials in addition to the compound represented by Chemical Formula 1, if necessary. Specific examples thereof include arylamine-based organic materials, carbazole-based compounds, conductive polymers, block copolymers having both conjugated portions and non-conjugated portions, and the like, but are not limited thereto. According to an exemplary embodiment of the present invention, the hole transport material is the ink composition or a cured product thereof.
The electron transport layer is a layer which accepts electrons from an electron injection layer and transports the electrons to a light emitting layer. An electron transport material is preferably a material having high electron mobility which may proficiently accept electrons from a cathode and transfer the electrons to a light emitting layer. Specific examples thereof include: Al complexes of 8-hydroxyquinoline; complexes including Alq3; 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 according to the related art. In particular, an appropriate cathode material is a typical material which has a low work function, followed by an aluminum layer or a silver layer. Specific examples thereof include cesium, barium, calcium, ytterbium, and samarium, in each case followed by an aluminum layer or a silver layer.
The electron injection layer is a layer which accepts electrons from an electrode. It is preferred that an electron injection material is excellent in ability to transport electrons and has an effect of accepting electrons from the cathode and an excellent electron injection effect for a light emitting layer or a light emitting material. Further, the electron injection material is preferably a material which prevents excitons produced from a light emitting layer from moving to a hole injection layer and is excellent in ability to form a thin film. Specific examples thereof include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidene methane, anthrone, and the like, and derivatives thereof, metal complex compounds, nitrogen-containing 5-membered ring derivatives, and the like, but are not limited thereto. Examples of the metal complex compounds 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-cresolato) gallium, bis(2-methyl-8-quinolinato)(1-naphtholato) aluminum, bis(2-methyl-8-quinolinato)(2-naphtholato) gallium, and the like, but are not limited thereto.
The electron blocking layer is a layer which may improve the service life and efficiency of a device by preventing electrons injected from an electron injection layer from passing through a light emitting layer and entering a hole injection layer. The electron-blocking layer may be formed between the light emitting layer and the hole injection layer, or between the light emitting layer and the layer which simultaneously injects and transports holes using the compound of the above-described Chemical Formula 2.
The hole blocking layer is a layer which blocks holes from reaching a cathode, and may be generally formed under the same conditions as those of the electron injection layer. Specific examples of the hole blocking layer material include oxadiazole derivatives or triazole derivatives, phenanthroline derivatives, aluminum complexes, and the like, but are not limited thereto.
The hole injection and transport layer may include materials for the above-described hole injection layer and hole transport layer.
The electron injection and transport layer may include materials for the above-described electron injection layer and electron transport layer.
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 according to the present disclosure may be a top emission type, a bottom emission type, or a dual emission type according to the material to be used.
An exemplary embodiment of the present invention provides an electronic device including an organic light emitting device including the above-described ink composition or a cured product thereof, or including an organic material layer formed using the ink composition.
The electronic device may include all of the interlayer insulation film of a semiconductor device, a color filter, a black matrix, an overcoat, a column spacer, a passivation film, a buffer coating film, a multilayer printed board insulation film, a cover coat of a flexible copper-clad board, a solder resist film, an insulation film of OLED, a protection film of a thin-film transistor of a liquid crystal display device, an electrode protection film and a semiconductor protection film of an organic EL device, an OLED insulation film, an LCD insulation film, a semiconductor insulation film, a solar light module, a touch panel, a display device such as a display panel, and the like, but is not limited thereto.
Hereinafter, the present invention will be described in detail with reference to Examples for specifically describing the present invention. However, the Examples according to the present invention may be modified into various different forms, and it should not be interpreted that the scope of the present invention is limited to the Examples to be described below. The Examples of the present invention are provided for more completely explaining the present invention to the person with ordinary skill in the art.
1-Bromo-4-fluorobenzene (27.9 mL, 255 mmol) was put into tetrahydrofuran (THF) (500 mL). After substitution with nitrogen, the mixture was cooled to −78° C. n-BuLi (2.5 M Hex) (96 mL, 240 mmol) was put into a dropping funnel and then slowly introduced into the reaction mixture. The resulting mixture was stirred at −78° C. for 30 minutes. 2-Bromofluorenone (38.9 g, 150 mmol) was added thereto. The mixture was stirred overnight while being slowly warmed to room temperature. After the reaction was terminated by adding distilled water thereto, extraction was performed with ethyl acetate and water. After an organic layer was collected, the organic layer was dried using MgSO4 and filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent, and Intermediate 1-1 was secured and used in the next reaction.
Intermediate 1-1 (53 g, 150 mmol) and phenol (70.6 g, 750 mmol) were put into a round bottom flask (RBF). After CH3SO3H (214 mL) was added thereto, the resulting mixture was stirred at 60° C. for 4 hours. After ice water was added thereto, extraction was performed with ethyl acetate and water. After an organic layer was collected, the organic layer was dried using MgSO4 and filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under dichloromethane (DCM)/heptane conditions to secure 40.6 g of Intermediate 1-2.
Intermediate 1-2 (45 g, 104 mmol), phenyl triflimide (PhNTf2) (81.8 g, 229 mmol) and 4-dimethylaminopyridine (DMAP) (2.54 g, 21 mmol) were put into a round bottom flask. Dichloromethane (416 mL) and triethylamine (TEA) (37.7 mL, 270 mmol) were added thereto, and the resulting mixture was stirred at room temperature (RT) for 1 hour. Extraction was performed with dichloromethane and a 3% aqueous HCl solution, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. Crystallization was performed under dichloromethane/heptane conditions to prepare Intermediate 1-3 (52.5 g).
Intermediate 1-3 (52.2 g, 92.7 mmol), potassium vinyltrifluoroborate (27.3 g, 204 mmol), Pd(dppf)Cl2 (3.4 g, 4.6 mmol) and K2CO3 (51.2 g, 971 mmol) were put into a round bottom flask. After substitution with nitrogen, THF (371 mL) and H2O (93 mL) were added thereto, and the resulting mixture was stirred at 90° C. for 4 hours. Extraction was performed with ethyl acetate and water, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under DCM/EtOH conditions to prepare Intermediate 1-4 (34 g).
4-Aminodibenzofuran (513 mg, 2.8 mmol), Intermediate 1-4 (2.53 g, 5.74 mmol), Pd(PtBu3)2 (72 mg, 0.14 mmol) and NaOtBu (1.08 g, 11.2 mmol) were put into RBF. After substitution with nitrogen, toluene (14 mL) was added thereto, and the resulting mixture was stirred at 90° C. for 1 hour. Extraction was performed with ethyl acetate and water, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under DCM/EtOH conditions to obtain 2.0 g of Compound 1. The synthesis of the compound was confirmed through LC-MS and NMR. MS: [M+H]+=904
NMR measurement value of Compound 1: 1H NMR (500 MHz, DMSO-d6) δ 8.07 (dd, 1H), 7.92 (d, 1H), 7.63 (dd, 4H), 7.39-7.24 (m, 10H), 7.21 (dd, 1H), 7.10 (m, 2H), 6.97-6.83 (m, 18H), 6.72 (dd, 2H), 5.75 (d, 2H), 5.21 (d, 2H)
Intermediate 1-2 (40 g, 92.7 mmol), 4-nitrobenzaldehyde (21.2 g, 139 mmol), Cu(OAc)2 (842 mg, 4.64 mmol) and Cs2CO3 (45.3 g, 139 mmol) were put into RBF. DMF (310 mL) was added thereto, and the resulting mixture was stirred at 100° C. for 4 hours. Extraction was performed with ethyl acetate and water, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under DCM/heptane conditions to secure 38.7 g of Intermediate 2-3.
After CH3PPh3Br (51.6 g, 144.6 mmol), KOtBu (16.2 g, 144.6 mmol) and THF (217 mL) were put into RBF, the resulting mixture was cooled to 0° C. A solution of Intermediate 2-3 (38.7 g, 72.3 mmol) dissolved in THF (144 mL) was added to the reaction mixture. The resulting mixture was stirred for 1 hour while being warmed to room temperature. Extraction was performed with ethyl acetate and water, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under DCM/EtOH conditions to secure 33.7 g of Intermediate 2-4.
3-Aminodibenzofuran (513 mg, 2.8 mmol), Intermediate 2-4 (3.1 g, 5.74 mmol), Pd(PtBu3)2 (72 mg, 0.14 mmol) and NaOtBu (1.08 g, 11.2 mmol) were put into RBF. After substitution with nitrogen, toluene (14 mL) was added thereto, and the resulting mixture was stirred at 90° C. for 1 hour. Extraction was performed with ethyl acetate and water, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under DCM/EtOH conditions to secure 2.9 g of Compound 2. The synthesis of the compound was confirmed through LC-MS and NMR. MS: [M+H]+=1088
NMR measurement value of Compound 2: 1H NMR (500 MHz, DMSO-d6) δ 8.11 (s, 1H), 8.07 (dd, 1H), 7.85 (d, 1H), 7.82 (dd, 4H), 7.46 (dd, 4H), 7.39-7.20 (m, 10H), 7.08 (m, 2H), 6.97-6.83 (m, 18H), 6.72 (dd, 2H), 6.65 (d, 4H), 5.75 (d, 2H), 5.21 (d, 2H)
Compound 3 was prepared in the same manner as in Synthesis Example A-1, except that 2-aminodibenzofuran was used instead of 4-aminodibenzofuran in (5) of Synthesis Example A-1. The synthesis of the compound was confirmed through LC-MS and NMR. MS: [M+H]+=904
NMR measurement value of Compound 3: 1H NMR (500 MHz, DMSO-d6) δ 8.08 (dd, 1H), 7.92 (d, 1H), 7.63 (dd, 4H), 7.39-7.24 (m, 10H), 7.21 (dd, 1H), 7.10 (m, 2H), 6.97-6.83 (m, 18H), 6.72 (dd, 2H), 5.75 (d, 2H), 5.21 (d, 2H)
2-Amino-9,9-dimethylfluorene (586 mg, 2.8 mmol), Intermediate 2-4 (3.1 g, 5.74 mmol), Pd(PtBu3)2 (72 mg, 0.14 mmol) and NaOtBu (1.08 g, 11.2 mmol) were put into RBF. After substitution with nitrogen, toluene (14 mL) was added thereto, and the resulting mixture was stirred at 90° C. for 1 hour. Extraction was performed with ethyl acetate and water, an organic layer was collected, and then the organic layer was dried using MgSO4 and then filtered. The filtrate was dried using a vacuum rotary concentrator to remove the organic solvent. After column purification, crystallization was performed under DCM/EtOH conditions to secure 2.6 g of Compound 4. The synthesis of the compound was confirmed through LC-MS and NMR. MS: [M+H]+=1114
NMR measurement value of Compound 4: 1H NMR (500 MHz, DMSO-d6) δ 7.95 (dd, 1H), 7.90 (dd, 1H), 7.84 (dd, 4H), 7.46 (dd, 4H), 7.39-7.20 (m, 11H), 7.08 (m, 2H), 6.97-6.83 (m, 18H), 6.72 (dd, 2H), 6.65 (d, 4H), 5.75 (d, 2H), 5.21 (d, 2H), 1.68 (s, 6H)
Compound 5 was prepared in the same manner as in Synthesis Example A-2, except that 4-aminodibenzofuran was used instead of 3-aminodibenzofuran in (3) of Synthesis Example A-2. The synthesis of the compound was confirmed through LC-MS and NMR. MS: [M+H]+=1088
NMR measurement value of Compound 5: 1H NMR (500 MHz, DMSO-d6) δ 8.07 (dd, 1H), 7.92 (d, 1H), 7.82 (dd, 4H), 7.46 (dd, 4H), 7.39-7.24 (m, 10H), 7.21 (dd, 1H), 7.10 (m, 2H), 6.97-6.83 (m, 18H), 6.72 (dd, 2H), 6.65 (d, 4H), 5.75 (d, 2H), 5.21 (d, 2H)
1-Bromo-2,3,5,6-tetrafluoro-4-vinylbenzene (2 g, 7.84 mmol) was put into THF (20 mL) in a 50-mL round bottom flask, and the resulting solution was stirred at −78° C. for 30 minutes. n-BuLi in hexane (3.45 mL, 8.63 mmol, 2.5 M) was slowly added to the solution, and the resulting mixture was stirred at −78° C. for 30 minutes. BCl3 (2.6 mL, 2.61 mmol, 1 M in heptane solution) was added to the reaction solution at −78° C. over 15 minutes. The resulting solution was slowly warmed to room temperature, the reaction solution was stirred overnight, and then water (30 mL) was added thereto. After the synthetic material was extracted with ethyl acetate (three times with 10 mL), the solvent was thoroughly removed. Water was completely removed by means of a Dean-stark using benzene, and the solid was filtered to prepare Intermediate D-1-1 (800 mg, yield 43%).
Intermediate D-1-1 (400 mg, 0.56 mmol), diphenyliodonium chloride (176 mg, 0.56 mmol), water (10 mL), and acetone (10 mL) were put into a 25-mL round bottom flask and stirred vigorously for 30 minutes. Extraction was performed using dichloromethane (three times with 10 mL) to remove the solvent, and the residue was dried to prepare Compound D-1 (Dopant 1) (552 mg, yield 100%).
MS: [M−H]−=711 (negative mode)
MS: [M+H]+=281 (positive mode)
Mg (193 mg, 7.92 mmol), I2 (4 mg), and THF (10 mL) were put into a 100-mL round bottom flask under a nitrogen atmosphere, and stirred for 30 minutes. 4-bromostyrene (1.04 mL, 7.92 mmol) was put thereinto, a water bath at 30° C. was placed under the round bottom flask, and the resulting mixture was stirred overnight. It was confirmed that the reaction solution had become black and Mg had been dissolved therein. The reaction solution was diluted by adding ether (5 mL) thereto. Tris(pentafluorophenyl)borane (1 g, 3.96 mmol) was dissolved in ether (5 mL), and the resulting solution was slowly added to the reaction solution for 30 minutes. The solution was stirred overnight. Na2CO3 (0.1 M, 80 mL, 8.0 mmol) was slowly added to the reaction solution. The organic solvent was extracted using ethyl acetate (three times with 20 mL), and the remaining water was removed over MgSO4. Additionally, distillation was conducted with benzene by using a Dean-stark in order to remove the remaining water and impurities. When about 10 mL of the solvent remained, the solution was cooled and filtered to prepare Intermediate D-2-1 (1.6 g, yield 64%).
Intermediate D-2-1 (100 mg, 0.16 mmol), distilled water (10 mL) and Ph2ICl (60 mg, 0.19 mmol) were put into a 25-mL round bottom flask and stirred for 1 hour. A precipitate was produced by adding acetone (15 mL) to the reaction solution, and the precipitate was filtered and dried to prepare Compound D-2 (Dopant 2) (140 mg, yield 100%).
MS: [M−H]−=615 (negative mode)
MS: [M+H]+=281 (positive mode)
Hole injection layer host 1 and hole injection layer dopant 1 were mixed at a weight ratio of 8:2. Thereafter, a mixture of the hole injection layer host 1 and the hole injection layer dopant 1 was added at a concentration of 2.0 wt % to a solvent in which 3-isopropylbiphenyl that is a solvent represented by Chemical Formula A, benzyl butyrate that is a first additional solvent, and dipropylene glycol monomethyl ether that is a second additional solvent were included and mixed in an amount of 10 wt %, 15 wt % and 75 wt %, respectively. The mixed and prepared solution was stirred for 24 hours and completely dissolved to prepare Ink Composition 1.
Ink Compositions 2 to 63 were prepared in the same manner as in Ink Composition Preparation Example 1, except that materials shown in the following Table 1 were used as the hole injection layer host 1, the hole injection layer dopant 1, the solvent represented by Chemical Formula A, the first additional solvent and the second additional solvent.
Hole injection layer host 1 and hole injection layer dopant 1 were mixed at a weight ratio of 8:2. Thereafter, a mixture of the hole injection layer host 1 and the hole injection layer dopant 1 was added at a concentration of 2.0 wt % to a solvent in which 3-isopropylbiphenyl that is a solvent represented by Chemical Formula A and benzyl butyrate that is a first additional solvent were included and mixed in an amount of 20 wt % and 80 wt %, respectively. The mixed and prepared solution was stirred for 24 hours and completely dissolved to prepare Ink Composition 64.
Ink Compositions 65 to 75 were prepared in the same manner as in Ink Composition Preparation Example 64, except that materials shown in the following Table 1 were used as the hole injection layer host 1, the hole injection layer dopant 1, the solvent, and the first additional solvent.
As the solvents used in Ink Compositions 29 to 56, tastromine (CAS #91-46-3), DELTA-TRIDECANOLACTONE (CAS #7370-92-5), 1-Nonylimidazole (CAS #53657-08-2) and N-Isopentyl-N-phenylpropionamide (CAS #63916-02-9) were each used.
After Ink Composition 1 was printed on an ITO substrate having banks formed thereon by an inkjet method, the printed substrate was put into a vacuum chamber, and the pressure was reduced from normal pressure to 2×10−2 torr for 60 seconds and from 2×10−2 torr to 2×10−6 torr for 180 seconds, and drying was performed at room temperature. After drying, the thin film was cured by performing a heat treatment under the conditions of N2 atmosphere and hot plate 230° C. for 1 hour. The thicknesses of pixels included in the cured thin film was measured using an optical profiler (model name: ContourGT-I) manufactured by Bruker, which is an optical thickness measuring device, and based on the measured thicknesses of the pixels, the thickness uniformity V between pixels was derived through the following Equation 1′. The derived values are shown in the following Table 2.
In Equation 1′,
The ITO substrate on which the bank is formed in Example 1 corresponds to
Except that the ink compositions shown in the following Table 2 were used instead of Ink Composition 1, preparation was performed in the same manner as in Example 1, and the thickness uniformity V was derived and shown in the following Table 2.
As shown in the contents of Table 2, it can be confirmed that Examples using the ink composition according to an exemplary embodiment of the present invention have a small value of thickness uniformity V of 0.4 or lower, Examples using particularly the solvent (specifically, butyl benzoate) of Chemical Formula C-1 as a first additional solvent while using two additional solvents have a very small value of thickness uniformity V of 0.2 or less, and Comparative Examples using ink compositions not corresponding to the present disclosure have a large value of thickness uniformity V of more than 0.4.
In this regard,
A glass substrate which was thin-film coated to have a thickness of 700 Å of ITO (indiumtinoxide) and patterned with hydrophobic banks was washed with distilled water for 30 minutes and then dried on a hot plate at 230° C. for 10 minutes. Ink Composition 1 in Table 1 was inkjet printed on a washed substrate patterned with banks, and heat-treated at 230° C. for 30 minutes, thereby forming a hole injection layer having a thickness of 30 nm. A hole transport layer having a thickness of 40 nm was formed on the hole injection layer by inkjet printing an ink prepared by dissolving the following α-NPD compound in cyclohexyl benzene at a concentration of 2 wt %. Thereafter, the glass substrate was transferred to a vacuum deposition machine, and then the following ADN compound and the following DPAVBi compound were vacuum-deposited on the hole transport layer at a weight ratio of 20:1 (ADN:DPAVBi) to have a thickness of 20 nm, thereby forming a light emitting layer. The following BCP compound was vacuum-deposited to have a thickness of 35 nm on the light emitting layer, thereby forming an electron injection and transport layer. A cathode was formed by depositing LiF and aluminum to have a thickness of 1 nm and 100 nm, respectively, on the electron injection and transport layer, thereby manufacturing an organic light emitting device.
Organic light emitting devices were manufactured using the ink composition in the following Table 3 instead of Ink Composition 1 in Example B-1.
It was confirmed that the organic light emitting devices manufactured in Examples B-1 to B-43 were driven. Through this, it was confirmed that the ink compositions according to the exemplary embodiments of the present invention can be applied to an organic light emitting device.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0122564 | Sep 2021 | KR | national |
This application is a national stage entry under 35 U.S.C. § 371 of International Application No. PCT/KR2022/013715 filed on Sep. 14, 2022, which claims priority from Korean Patent Application No. 10-2021-0122564 filed on Sep. 14, 2021, all the disclosures of which are incorporated by reference herein.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2022/013715 | 9/14/2022 | WO |
