TW201602308A - Material for phosphorescent light-emitting element - Google Patents

Abstract

A composition formed of a mixture of compounds having similar thermal evaporation properties that are pre-mixed into to an evaporation source that can be used to coevaporate the mixture of compounds into the emissive layer of a phosphorescent OLED via vacuum thermal evaporation process is disclosed.

Description

Material for phosphorescent light-emitting elements

The present invention relates to an organometallic phosphorescent dopant/organic host compound material combination that can be advantageously used in an organic light-emitting device; and a method of fabricating an organic light-emitting device comprising the organometallic phosphorescent dopant/host compound material combination. More particularly, the present invention relates to an evaporated premix comprising an organometallic phosphorescent dopant and an organic host compound to provide a highly uniform host: dopant ratio to the organic film. The consistency of the vaporized premixed films allows for precise optimization of material parameters and reliable performance results in the devices in which they are used.

Optical electronic devices utilizing organic materials are becoming increasingly popular for several reasons. Many of the materials used to make such devices are relatively inexpensive, and thus organic optical electronic devices have the potential to achieve cost advantages over inorganic devices. Additionally, the inherent properties of organic materials, such as their flexibility, can make them well suited for specific applications, such as fabrication on flexible substrates. Examples of organic optical electronic devices include organic light-emitting devices (OLEDs), organic photoelectric crystals, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can have performance advantages over conventional materials. For example, the wavelength at which the organic emissive layer emits light can generally be readily adjusted with a suitable dopant.

OLEDs utilize an organic film that emits light when a voltage is applied to the device. OLEDs are becoming more and more compelling for applications such as flat panel displays, lighting and backlighting technology. Several OLED materials and configurations are described in U.S. Patent Nos. 5,844,363, 6, 303, 238, and 5, 707, 745, the disclosures of each of

One application for phosphorescent emissive molecules is a full color display. Industry standards for such displays require pixels that are suitable for emitting a particular color (referred to as a "saturated" color). Specifically, these standards require saturated red, green, and blue pixels. Color can be measured using the CIE coordinates well known in the art.

An example of a green emitting molecule is tris(2-phenylpyridine)indole, denoted Ir(ppy) ₃ , which has the following structure:

In this figure and in the figures that follow, the coordination bonds from nitrogen to metal (here, Ir) are depicted as straight lines.

As used herein, the term "organic" includes polymeric materials as well as small molecule organic materials that can be used to fabricate organic optical electronic devices. "Small molecule" means any organic material that is not a polymer, and "small molecules" may actually be quite large. In some cases, small molecules can include repeating units. For example, the use of a long chain alkyl group as a substituent does not remove the molecule from the "small molecule" category. Small molecules can also be incorporated into the polymer, for example as pendant groups on the polymer backbone or as part of the backbone. Small molecules can also serve as a core part of a dendrimer composed of a series of chemical shells built on the core. The core portion of the dendrimer can be a fluorescent or phosphorescent small molecule emitter. Dendrimers can be "small molecules" and all dendrimers currently used in the field of OLEDs are small molecules.

As used herein, "top" means the farthest from the substrate, and "bottom" means the closest to the substrate. In the case where the first layer is described as being "positioned" on the second layer "on", the first layer is placed farther from the substrate. Unless the first layer is "contacted" with the second layer, otherwise There may be other layers between the first and second layers. For example, even if various organic layers are present between the cathode and the anode, the cathode can be described as being "placed" on the anode.

As used herein, "solution treatable" means capable of being dissolved, dispersed or transported in a liquid medium in the form of a solution or suspension and/or deposited from a liquid medium.

When the salty ligand directly contributes to the photosensitive nature of the emissive material, the ligand may be referred to as "photosensitive". When the salt-donating ligand does not contribute to the photosensitive nature of the emissive material, the ligand may be referred to as "assisted", but an auxiliary ligand may alter the properties of the photosensitive ligand.

As used herein, and as will be understood by those skilled in the art, the first "highest occupied molecular orbital" (HOMO) or "minimum unoccupied molecular orbital" (LUMO) energy can be obtained if the first energy level is closer to the vacuum level. Level "greater than" or "above" the second HOMO or LUMO energy level. Since the ionization potential (IP) is measured as a negative energy relative to the vacuum level, the higher HOMO level corresponds to an IP with a smaller absolute value (a less negative IP). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) with a smaller absolute value (an EA with less negative). On the conventional energy level diagram, the vacuum level is at the top and the LUMO level of the material is higher than the HOMO level of the same material. The "higher" HOMO or LUMO level appears to be closer to the top of the figure than the "lower" HOMO or LUMO level.

As used herein, and as will be understood by those skilled in the art, if the first work function has a higher absolute value, the first work function is "greater than" or "higher" than the second work function. Since the work function is usually measured as a negative relative to the vacuum level, this means that the "higher" work function is more negative. On the conventional energy level diagram, the vacuum level is at the top, and the "higher" work function is described as being farther away from the vacuum level in the downward direction. Therefore, the definition of HOMO and LUMO energy levels follows a different convention from the work function.

Further details regarding the OLED and the definitions described above can be found in U.S. Patent No. 7,279,704, the disclosure of which is incorporated herein by reference.

A material combination is provided; and an organic light emitting device wherein an emissive layer comprises the material combination. This material combination contains premixed materials suitable for co-evaporation. The premixed material comprises a physical mixture of a first compound and a second compound, wherein the first compound is an organometallic phosphorescent dopant compound having the formula: L ₂ MX, LL'MX, LL'L"M or LMXX' Wherein L, L', L", X and X' are unequal bidentate ligands, and M is a metal having an atomic weight greater than 40, wherein L, L' and L" are carbon blended via sp ² a single anion non-equivalent bidentate ligand to M, wherein the organometallic phosphorescent dopant compound is selected from the group consisting of an organometallic platinum compound, an organometallic ruthenium compound, and an organometallic ruthenium compound, and wherein the organometallic platinum compound The ruthenium compound and the ruthenium compound optionally include an aromatic ligand, and the second compound comprises an organoheteroaromatic host compound having the formula (1):

Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (1a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (1b):

Ring B is a heterocyclic ring represented by the formula (1c):

Rings A and B are each condensed with an adjacent ring; each R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic group of 3 to 17 carbon atoms. Heterocyclic group.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring; m represents 0 or an integer of 1 to 2.

n represents 0 or an integer of 1. X ¹ is O or S or N-Ar ¹ or N, wherein Ar ¹ is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings Heterocyclic group.

X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic heterocyclic ring of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings base.

100‧‧‧Organic lighting device

110‧‧‧Substrate

115‧‧‧Anode

120‧‧‧ hole injection layer

125‧‧‧ hole transport layer

130‧‧‧Electronic barrier

135‧‧‧ emission layer

140‧‧‧ hole barrier

145‧‧‧Electronic transport layer

150‧‧‧electron injection layer

155‧‧‧Protective layer

160‧‧‧ cathode

162‧‧‧First conductive layer

164‧‧‧Second conductive layer

200‧‧‧OLED

210‧‧‧Substrate

215‧‧‧ cathode

220‧‧‧Emission layer

225‧‧‧ hole transport layer

230‧‧‧Anode

Figure 1 shows an organic light emitting device.

Figure 2 illustrates an inverted organic light-emitting device without a separate electron transport layer.

Generally, an OLED comprises at least one organic layer disposed between an anode and a cathode and electrically connected to an anode and a cathode. When a current is applied, the anode is injected into the hole and the cathode injects electrons into the organic layer. The injected holes and electrons each migrate toward the oppositely charged electrode. When the electrons and holes are confined to the same molecule, an "exciton" is formed, which is a localized electron-hole pair having an excited energy state. When an exciton relaxes via a light emission mechanism, light is emitted. In some cases, excitons can be limited to excimer or excited complexes. Non-radiative mechanisms, such as thermal relaxation, may also occur, but are generally considered undesirable.

The original OLED uses an emissive molecule that emits light from a single state ("fluorescent"), as disclosed in, for example, U.S. Patent No. 4,769,292, the disclosure of which is incorporated herein in its entirety. firefly Light emission typically occurs over a time range of less than 10 nanoseconds.

Recently, OLEDs having emissive materials derived from triplet emission ("phosphorescence") have been demonstrated. Baldo et al., "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices", Nature, Vol. 395, pp. 151-154, 1998; ("Baldo-I") and Baldo et al. "Very high-efficiency green organic light- "Embodiment devices based on electrophosphorescence", Appl. Phys. Lett., Vol. 75, No. 3, pp. 4-6 (1999) ("Baldo-II"), which is incorporated by reference in its entirety. Phosphorescence is described in more detail in U.S. Patent No. 7,279,704, the disclosure of which is incorporated herein by reference.

FIG. 1 illustrates an organic light emitting device 100. The figures are not necessarily drawn to scale. The device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, an emission layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, and a protective layer 155. And a cathode 160. The cathode 160 is a composite cathode having a first conductive layer 162 and a second conductive layer 164. Device 100 can be fabricated by sequentially depositing the layers described. The nature and function of these various layers, as well as exemplary materials, are described in more detail in lines 6-10 of US 7,279,704, incorporated by reference.

There are more instances of each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Patent No. 5,844,363, which is incorporated herein by reference. An example of a p-doped hole transport layer is m-MTDATA doped with F ₄ -TCNQ at a molar ratio of 50:1, as disclosed in US Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. Revealed in the number. Examples of emissive materials and host materials are disclosed in U.S. Patent No. 6,303,238, the disclosure of which is incorporated herein by reference. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated herein by reference. An example of a cathode comprising a thin layer of a metal such as Mg:Ag and an overlying transparent, electrically conductive, sputter-deposited ITO layer is disclosed in U.S. Patent Nos. 5,703,436 and 5,707,745 each incorporated by reference. Composite cathode. The principles and use of the barrier layer are described in more detail in U.S. Patent No. 6,097,147, the disclosure of which is incorporated herein by reference. An example of an injection layer is provided in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference. A description of the protective layer can be found in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety.

Figure 2 shows the inverted OLED 200. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole transport layer 225, and an anode 230. Device 200 can be fabricated by sequentially depositing the layers described. Because the most common OLED configuration has a cathode disposed on the anode and the device 200 has a cathode 215 disposed under the anode 230, the device 200 can be referred to as an "inverted" OLED. In a corresponding layer of device 200, materials similar to those described with respect to device 100 can be used. FIG. 2 provides an example of how some layers may be omitted from the structure of device 100.

The simple layered structure illustrated in Figures 1 and 2 is provided as a non-limiting example, and it should be understood that embodiments of the invention may be utilized in connection with a wide variety of other structures. The specific materials and structures described are exemplary in nature and other materials and structures may be used. The functional OLED may be implemented by combining the various layers described in different ways based on design, performance and cost factors, or several layers may be omitted altogether. Other layers not specifically described may also be included. Materials other than the materials specifically described may be used. While many of the examples provided herein describe various layers as comprising a single material, it should be understood that a combination of materials (such as a mixture of host and dopant) or, more generally, a mixture may be used. Also, the layers can have various sub-layers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 225 transmits holes and injects holes into emissive layer 220, and may be described as a hole transport layer or a hole injection layer. In one embodiment, the OLED can be described as having an "organic layer" disposed between the cathode and the anode. This organic layer may comprise a single layer or may be further packaged A plurality of layers comprising different organic materials as described, for example, with respect to Figures 1 and 2.

It is also possible to use a structure and a material that is not specifically described, such as an OLED (PLED) comprising a polymeric material, such as disclosed in U.S. Patent No. 5,247,190, issued to s. As another example, an OLED having a single organic layer can be used. The OLEDs can be stacked, for example, as described in U.S. Patent No. 5,707,745, issued to A.S. The OLED structure can be separated from the simple layered structure illustrated in Figures 1 and 2. For example, the substrate may include an angled reflective surface to improve the out-coupling, such as the mesa structure as described in U.S. Patent No. 6,091,195, issued to the name of the entire disclosures of U.S. Pat. The pit structure described in U.S. Patent No. 5,834,893, the disclosure of which is incorporated herein in its entirety.

Any of the various embodiments may be deposited by any suitable method, unless otherwise specified. For the organic layer, preferred methods include thermal evaporation, ink jet (such as described in U.S. Patent Nos. 6,013,982 and 6,087,196, incorporated by reference in their entirety), and organic vapor deposition (OVPD). </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Said). Other suitable deposition methods include spin coating and other solution based methods. The solution based process is preferably carried out under nitrogen or an inert atmosphere. For other layers, preferred methods include thermal evaporation. The preferred method of patterning includes deposition by a mask, cold soldering (such as described in U.S. Patent Nos. 6,294,398 and 6,468,819, incorporated by reference in its entirety) and in a deposition method such as inkjet and OVJD. Some methods are associated with patterning. Other methods are also available. The material to be deposited can be modified to be compatible with the particular deposition method. For example, a substituent such as an alkyl group and an aryl group having a branched or unbranched group and preferably containing at least 3 carbons may be used in a small molecule to enhance its ability to undergo solution treatment. Substituents having 20 or more carbons can be used, and 3-20 carbons are Good range. A material having an asymmetric structure may have better solution treatability than a material having a symmetrical structure because the asymmetric material may have a lower recrystallization tendency. Dendrimer substituents can be used to enhance the ability of small molecules to undergo solution processing.

Devices made in accordance with embodiments of the present invention can be incorporated into a wide variety of consumer products, including flat panel displays, computer monitors, televisions, billboards, lamps for internal or external lighting, and/or signaling , heads-up display, fully transparent display, flexible display, laser printer, telephone, mobile phone, personal digital assistant (PDA), laptop, 3-D display, digital camera, camcorder, viewfinder , microdisplays, vehicles, large-area walls, theater or stadium screens, or signs. Various control mechanisms can be used to control the devices made in accordance with the present invention, including passive matrices and active matrices. Many of these devices are intended for use in a temperature range that is comfortable for humans, such as 18 degrees Celsius to 30 degrees Celsius, and more preferably at room temperature (20-25 degrees Celsius).

The materials and structures described herein can be applied to devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors can use such materials and structures. More generally, organic materials such as organic transistors can use such materials and structures.

The terms halo, halo, alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclyl, aryl, aromatic and heteroaryl are known in the art and are defined by way of citation Incorporating the columns 7-32 of US 7,279,704 herein.

Here, combinations of organometallic phosphorescent dopants and heteroaromatic host compounds can be advantageously utilized in organic light-emitting devices to provide improved performance and improved device fabrication. In particular, the device can be fabricated by co-evaporation or pre-mixing-evaporation with high consistency. High performance liquid chromatography (HPLC) results for exemplary materials show a consistent ratio of host compound to organometallic phosphorescent dopant for the deposited film. The evaporated mixed material film disclosed herein can be used in an emissive layer of a phosphorescent OLED.

Premixed and vaporized host materials and emissive dopant materials have been previously reported in the literature. See EP1156536. It is also known to select two or more materials having similar thermal properties for premix evaporation. See, for example, US 5,981,092 and PCT/US2004/002710. It is desirable to have a convenient and consistent way to simultaneously evaporate dopants and host materials. In a phosphorescent OLED, an emissive layer comprising a host compound and an organometallic dopant compound, typically a host: a dopant layer is used as the emissive material. The main body significantly affects the device voltage, efficiency and lifetime. Device performance can be further enhanced by the presence of other materials (such as auxiliary dopants) that are carefully selected in the emissive layer. See, for example, US20040258956 and US20070247061.

When two or more materials are deposited, the simultaneous evaporation of individual materials from their own source is the most common method, which is hereinafter referred to as co-evaporation. Co-evaporation control can be difficult and the deposition equipment needs to have more individual control and a source of monitoring. Therefore, it is desirable to evaporate a mixture of materials from a single source by a process known as premixing-evaporation. It is desirable that the premixed mixture evaporate uniformly and uniformly and form a deposited film composed of two or more materials in a ratio similar to the mixing ratio in the source. Under high vacuum, the mean free path of the molecule is much larger than the size of the device when the fluid is in a free molecular flow regime. The evaporation rate is no longer dependent on pressure. That is, because the continuous assumption of fluid dynamics is no longer applicable, mass transfer is determined by molecular dynamics rather than fluid dynamics. For materials that do not melt during evaporation, a direct transition from the solid phase to the gas phase occurs. When two or more materials are mixed and evaporated from the same source under high vacuum, various factors may promote evaporation, such as evaporation temperatures of individual materials, miscibility of different materials, and different phase transitions. Without being bound by theory, it is believed that similar evaporation temperatures of the first material and the second material promote evaporation uniformity.

For the purposes herein, evaporation temperature is defined as the temperature at which a material can be deposited on a substrate at a predetermined rate under high vacuum. For example, as used herein, the evaporation temperature is a source of organic material such as thermal evaporation at a rate suitable for device fabrication (in the case of the present invention, about 2-3 A/s at about 10"-10" torr). The temperature measured during the period. Since the evaporation temperature depends on the molecular weight of the material and the intermolecular interaction, derivatives having the same molecular modification will have the same molecular weight difference and may have similar intermolecular interactions. For example, When the first compound and the second compound are premixed and evaporated in good agreement, if the first compound is substituted with a phenyl group and the second compound is also substituted with a phenyl group, the molecular weight added to the first compound and the second compound is 77 atomic mass units (amu). In addition, if the phenyl group induces a similar molecular interaction with the first compound and the second compound, the evaporation temperature of the first compound having a phenyl group and the second compound having a phenyl group may be similar and a mixture thereof may also be applied. Premixed evaporation. Further, even if the conditions in the evaporation chamber are different, the first compound and the second compound can be similarly expressed. It is also desirable that premixed evaporation produces a similar device performance and lifetime compared to co-evaporation. Thus, premixing the dopant and host compound in an evaporation source provides uniform and consistent evaporation of two or more materials, thereby forming a sink consisting of two or more materials at a similar ratio to the premix ratio. Laminated.

Provided herein are novel combinations of materials in which an organic host compound is physically mixed with an organometallic phosphorescent dopant compound, which is suitable for premix evaporation or co-evaporation. For the premixed evaporation aspect of the present invention, the organic host compound is physically mixed with the organometallic phosphorescent dopant. The particular combination of materials disclosed herein exhibits unexpected results by providing a highly consistent ratio of host compound to organometallic phosphorescent dopant in the film deposited from the premix. Without being bound by theory, the salt metal organic phosphorescent dopants and heteroaromatic host compounds have strong intermolecular interactions. Therefore, consistent deposition characteristics are obtained by adjusting the deposition temperatures of the respective compounds. Accordingly, it is believed that the combination of the first compound selected from the organometallic phosphorescent dopant compounds disclosed herein and the second compound selected from the organic host compounds disclosed herein synergistically improves the properties of the resulting combination.

The organometallic phosphorescent dopant component of the material combination can act as an emissive dopant or it can act as an auxiliary dopant. Another organometallic phosphorescent compound present in the dopant emissive layer can act as an emissive dopant if the organometallic phosphorescent dopant component of the premix acts as a co-dopant. Conversely, where the organometallic phosphorescent dopant component of the premix acts as an emissive dopant, the emissive layer may optionally contain another organometallic phosphorescent compound that acts as an auxiliary dopant. In any case, regardless of the organometallic phosphorescence doping in the mixed material The agent component acts as an emissive dopant or an auxiliary dopant, and the relative triplet energy of the material in the emissive layer can be depicted as follows:

Emitter dopant <auxiliary dopant <body material

An organic light emitting device and a material for its emissive layer are provided. The organic light emitting device includes a first electrode, a second electrode, and a first organic layer disposed between the first electrode and the second electrode, wherein the first organic layer comprises an organic composition. The organic composition comprises a first compound and a second compound, the first compound being an organometallic compound represented by the formula L ₂ MX, LL'MX, LL'L"M or LMXX', wherein L, L', L", X And X' is an unequal bidentate ligand, and M is a metal forming an octahedral complex, wherein L, L' and L" are single anions coordinated to carbon by sp ² and coordinated to a hetero atom by M Not equivalent to a bidentate ligand, and the second compound has a heteroaromatic structure.

In one aspect, the first compound may be a compound selected from the group consisting of a phosphorescent organometallic platinum compound, an organometallic ruthenium compound, and an organometallic ruthenium compound. The organometallic platinum compound, the cerium compound, and the cerium compound may each include an aromatic ligand.

In another aspect, the first compound comprises a phosphorescent organometallic compound having a substituted chemical structure represented by the following chemical structure:

Wherein M is Ir, Pt or Os; each R 'is independently selected from the group consisting of: H, alkyl, alkenyl, alkynyl, _{alkylaryl, CN, CF 3, C n} F 2n + 1, trifluoromethoxy Vinyl, CO ₂ R", C(O)R", NR" ₂ , NO ₂ , OR", halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or heterocyclic, And wherein each R" is independently H, alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or aralkyl; Ar', Ar", Ar''' and Ar'''' Each independently represents a substituted or unsubstituted aryl or heteroaryl non-fused substituent on a phenylpyridine ligand; a is 0 or 1; b is 0 or 1; c is 0 or 1; Is 0 or 1; m is 1 or 2; n is 1 or 2; m+n is the maximum number of ligands which can be coordinated to M; and wherein at least one of a, b, c and d is 1 And when at least one of a and b is 1 and at least one of b and c is 1, at least one of 'Ar' and Ar" is different from Ar'' and Ar''' At least one.

The second compound comprises an organoheteroaromatic host compound of formula (1):

Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (1a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (1b):

Ring B is a heterocyclic ring represented by the formula (1c):

Rings A and B are each condensed with an adjacent ring; in the formulae (1a) and (1b), X ¹ is O or S or N-Ar ¹ or N, wherein Ar ¹ is an aromatic hydrocarbon group of 6 to 50 carbon atoms Or an aromatic heterocyclic group of 3 to 50 carbon atoms having a group of more than 5 condensed rings.

R is independently selected from the group consisting of hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic heterocyclic group of 3 to 17 carbon atoms.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring, and X ¹ is O or S or N-Ar ¹ or N, wherein Ar ¹ is an aromatic group of 6 to 50 carbon atoms A hydrocarbon group or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

m represents 0 or an integer n of 1 to 2 represents 0 or an integer 1.

In the formula (1c), X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or 3 to 50 excluding a group having more than 5 condensed rings An aromatic heterocyclic group of a carbon atom.

In the above-mentioned, examples of Y or Ar ¹ or Ar ² may include a t-valent or monovalent group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And two or more such groups may be arbitrarily linked. Further, Y is a t-valent group, and Ar ¹ and Ar ² are monovalent groups.

The second compound preferably contains a heteroaromatic host compound represented by the following chemical formula (2):

Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (2a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (2b):

Ring B is a heterocyclic ring represented by the formula (2c):

Rings A and B are condensed with adjacent rings, respectively; In the formulae (2a) and (2b), R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic hetero atom of 3 to 17 carbon atoms. Ring base.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring; m represents 0 or an integer n of 1 to 2 represents 0 or an integer of 1.

In the formula (2c), X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or 3 to 50 excluding a group having more than 5 condensed rings An aromatic heterocyclic group of a carbon atom.

In the examples of formula (2) mentioned above, Y or Ar ² may comprise a t-valent or monovalent group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And two or more such groups may be arbitrarily linked. Further, Y is a t-valent group, and Ar ² is a monovalent group.

The second compound more preferably contains a heteroaromatic host compound represented by the following chemical formula (3):

In the formula (3), Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (3a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (3b):

Ring B is a heterocyclic ring represented by the formula (3c):

Wherein rings A and B are condensed with adjacent rings at any position, respectively.

In the formulae (3a) and (3b), each R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic group of 3 to 17 carbon atoms. Heterocyclic group.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring.

In the formula (3c), Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group condensing more than 5 rings.

In the examples of formula (3) mentioned above, Y or Ar ² may comprise a t-valent or monovalent group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And two or more such groups may be arbitrarily linked. Further, Y is a t-valent group, and Ar ² is a monovalent group.

In a particular aspect, the set of non-hydrogen substituents selected for each independent R' is the same as the set of non-hydrogen substituents selected for R. As discussed above, the first compound and the derivative of the second compound having the same molecular modification will have the same molecular weight difference and may have similar intermolecular interactions. Therefore, the first compound having the same substituent and the second compound The material is suitable for premixing.

In one aspect, the first compound can be selected from, but not limited to, a group consisting of:

Methods for preparing such compounds are disclosed in U.S. Patent Application Publication No. In 2011/227049, it is incorporated herein by reference in its entirety.

The second compound represented by the general formulae (1) and (2) and (3) may be selected from, but not limited to, a group consisting of:

Some examples of methods of preparing such compounds are disclosed in U.S. Patent Application Publication Nos. 2009/0302742, 2010/0187977, and No. 2012/0001165, the disclosures of each of

As discussed above, the first compound and the derivative of the second compound having the same molecular modification will have the same molecular weight difference and may have similar intermolecular interactions. Therefore, the first compound and the second compound having the same substituent can be applied to premixing.

In another aspect, the apparatus further comprises a second organic layer different from the first organic layer, and the second organic layer is a non-emissive layer. Preferably, the second organic layer is a barrier layer.

In one aspect, the first electrode is an anode and the second organic layer is deposited on the anode.

In one aspect, the evaporation temperature of the first compound is within 30 ° C of the evaporation temperature of the second compound.

In one aspect, the organic composition comprises from about 5% to about 95% of the first compound and from about 5% to about 95% of the second compound.

In one aspect, the device is an organic light emitting device. In another aspect, the device is a consumer product.

In addition, a method of fabricating an organic light-emitting device is provided. The device includes a first electrode, a second electrode, and a first organic layer disposed between the first electrode and the second electrode. The first organic layer comprises an organic composition comprising a first compound and a second compound. In one aspect, the first compound and the second compound are physically mixed prior to device fabrication and evaporation from a single source. The method includes providing a substrate having a first electrode disposed thereon, the organic composition Depositing on the first electrode; and depositing the second electrode on the first organic layer.

The organic composition comprises a first compound and a second compound, the first compound being an organometallic compound represented by the formula L ₂ MX, LL'MX, LL'L"M or LMXX', wherein L, L', L", X And X' is an unequal bidentate ligand, and M is a metal forming an octahedral complex, wherein L, L' and L" are single anions coordinated to carbon by sp ² and coordinated to a hetero atom by M Not equivalent to a bidentate ligand, and the second compound is a compound having a heteroaromatic structure.

In one aspect, the first compound may be a compound selected from the group consisting of a phosphorescent organometallic platinum compound, an organometallic ruthenium compound, and an organometallic ruthenium compound. The organometallic platinum compound, the cerium compound, and the cerium compound may each include an aromatic ligand.

In another aspect, the first compound comprises a phosphorescent organometallic compound having a substituted chemical structure represented by the following chemical structure:

Wherein M is Ir, Pt or Os; each R 'is independently selected from the group consisting of: H, alkyl, alkenyl, alkynyl, _{alkylaryl, CN, CF 3, C n} F 2n + 1, trifluoromethoxy Vinyl, CO ₂ R", C(O)R", NR" ₂ , NO ₂ , OR", halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or heterocyclic, And wherein each R" is independently H, alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or aralkyl; Ar', Ar", Ar''' and Ar'''' Each independently represents a substituted or unsubstituted aryl or heteroaryl non-fused substituent on a phenylpyridine ligand; a is 0 or 1; b is 0 or 1; c is 0 or 1; Is 0 or 1; m is 1 or 2; n is 1 or 2; m+n is the maximum number of ligands which can be coordinated to M; and wherein at least one of a, b, c and d is 1 And when at least one of a and b is 1 and at least one of b and c is 1, at least one of Ar' and Ar" is different from Ar'' and Ar''' At least one.

The second compound comprises an organoheteroaromatic host compound of formula (1):

Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (1a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (1b):

Ring B is a heterocyclic ring represented by the formula (1c):

Rings A and B are each condensed with an adjacent ring; in the formulae (1a) and (1b), X ¹ is O or S or N-Ar ¹ or N, wherein Ar ¹ is an aromatic hydrocarbon group of 6 to 50 carbon atoms Or an aromatic heterocyclic group of 3 to 50 carbon atoms having a group of more than 5 condensed rings.

R is independently selected from the group consisting of hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic heterocyclic group of 3 to 17 carbon atoms.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring, and X ¹ is O or S or N-Ar ¹ or N, wherein Ar ¹ is an aromatic group of 6 to 50 carbon atoms A hydrocarbon group or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

m represents 0 or an integer n of 1 to 2 represents 0 or an integer 1.

In the formula (1c), X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or 3 to 50 excluding a group having more than 5 condensed rings An aromatic heterocyclic group of a carbon atom.

In the above-mentioned, examples of Y or Ar ¹ or Ar ² may include a t-valent or monovalent group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And two or more such groups may be arbitrarily linked. Further, Y is a t-valent group, and Ar ¹ and Ar ² are monovalent groups.

The second compound preferably contains a heteroaromatic host compound represented by the following chemical formula (2):

Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (2a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (2b):

Ring B is a heterocyclic ring represented by the formula (2c):

Rings A and B are each condensed with an adjacent ring; each R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic group of 3 to 17 carbon atoms. Heterocyclic group.

In the formulae (2a) and (2b), R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic hetero atom of 3 to 17 carbon atoms. Ring base.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring; m represents 0 or an integer n of 1 to 2 represents 0 or an integer of 1.

In the formula (2c), X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or 3 to 50 excluding a group having more than 5 condensed rings An aromatic heterocyclic group of a carbon atom.

In the examples of formula (2) mentioned above, Y or Ar ² may comprise a t-valent or monovalent group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And two or more such groups may be arbitrarily linked. Further, Y is a t-valent group, and Ar ² is a monovalent group.

The second compound more preferably contains a heteroaromatic host compound represented by the following chemical formula (3):

In the formula (3), Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings.

t represents an integer from 1 to 3, so that when t is greater than 2, each Z may be the same or different Z is represented by the formula (3a):

Wherein ring A is an aromatic hydrocarbon ring represented by formula (3b):

Ring B is a heterocyclic ring represented by the formula (3c):

Wherein rings A and B are condensed with adjacent rings at any position, respectively.

In the formulae (3a) and (3b), each R is independently selected from hydrogen, an aliphatic hydrocarbon having 1 to 10 carbon atoms An aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic heterocyclic group of 3 to 17 carbon atoms.

In the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring.

In the formula (3c), Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group condensing more than 5 rings.

In the examples of formula (3) mentioned above, Y or Ar ² may comprise a t-valent or monovalent group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And two or more such groups may be arbitrarily linked. Further, Y is a t-valent group, and Ar ² is a monovalent group.

In a particular aspect, the set of non-hydrogen substituents selected for each independent R' is the same as the set of non-hydrogen substituents selected for R, and the method further comprises mixing prior to depositing the organic composition on the first electrode. The first compound and the second compound.

In one aspect, the first compound can be selected from, but not limited to, a group consisting of:

And the second compound represented by the general formulae (1) and (2) and (3) may be selected from, but not limited to, a group consisting of:

In one aspect, the first compound and the second compound are premixed together and evaporated from a single source.

In one aspect, the organic composition comprises from about 5% to about 95% of the first compound and from about 5% to about 95% of the second compound.

In one aspect, the evaporation temperature of the first compound is within 30 ° C of the evaporation temperature of the second compound. In another aspect, the evaporation temperature of the first compound is within 10 ° C of the evaporation temperature of the second compound.

In one aspect, the first electrode is an anode and the first organic layer is deposited on the anode.

In one aspect, the method further comprises depositing a second organic layer different from the first organic layer, and the second organic layer is a non-emissive layer. In another aspect, the second organic layer is a barrier layer.

Materials described herein as being usable for a particular layer in an organic light-emitting device can be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in conjunction with a variety of host, transport layer, barrier layer, implant layer, electrodes, and other layers that may be present. The materials described or referenced below are non-limiting examples of materials that can be used in combination with the compounds disclosed herein, and those skilled in the art can readily consult the literature to identify other materials that can be used in combination.

In addition to and/or in combination with the materials disclosed herein, many hole injection materials, hole transport materials, host materials, dopant materials, exciton/hole barriers can be used in OLEDs. Materials, electron transport and electron injection materials.

Hole injection material / hole transmission material:

The hole injection/transport material used in the present invention is not particularly limited, and any compound can be used as long as the compound is typically used as a hole injection/transport material. Examples of the material include, but are not limited to, phthalocyanine or porphyrin derivatives; aromatic amine derivatives; indolocarbazole derivatives; fluorocarbon-containing polymers; polymers having conductive dopants; Conductive polymers such as PEDOT/PSS; self-assembling monomers derived from compounds such as phosphonic acid and decane derivatives; metal oxide derivatives such as MoO _x ; p-type semiconductor organic compounds such as 1, 4, 5, 8 , 9,12-hexazaheterotriphenyl hexacarbonitrile; a metal complex, and a crosslinkable compound.

Examples of the aromatic amine derivative used in the HIL or HTL include, but are not limited to, the following general structure:

Each of Ar ¹ to Ar ⁹ is selected from the group consisting of aromatic hydrocarbon ring compounds such as benzene, biphenyl, terphenyl, terphenyl, naphthalene, anthracene, anthracene, phenanthrene, anthracene, anthracene , , hydrazine, hydrazine; a group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzo Selenium, carbazole, indolocarbazole, pyridylpurine, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, triazole, dioxazole, thiadiazole , pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxazine, oxadiazine, hydrazine, benzimidazole, carbazole, anthraquinone, benzoxazole, benzoisoxine Oxazole, benzothiazole, quinoline, isoquinoline, Porphyrin, quinazoline, quinololine, naphthyridine, pyridazine, acridine, dibenzopyran, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furobipyridine, Benzothienopyridine, thienobipyridine, benzoselenopyridine and selenophenodipyridine; and a group consisting of 2 to 10 cyclic structural units selected from aromatic hydrocarbon ring groups And the same type or different types of groups of the aromatic heterocyclic group, and directly or via at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a ruthenium atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group They are linked to each other. Each Ar is further substituted with a substituent selected from the group consisting of hydrogen, alkyl, alkoxy, amine, alkenyl, alkynyl, aralkyl, heteroalkyl, aryl and heteroaryl.

In one aspect, Ar ¹ to Ar ^{9 are} independently selected from the group consisting of:

Wherein k is an integer from 1 to 20; X ¹ to X ⁸ are CH or N; and Ar ¹ has the same group as defined above.

Examples of metal complexes used in HIL or HTL include, but are not limited to, the following formula:

Wherein M' is a metal having an atomic weight greater than 40; (Y ¹ -Y ² ) is a bidentate ligand, Y ¹ and Y ^{2 are} independently selected from C, N, O, P and S; L is an auxiliary ligand The bit body; m is an integer value from 1 to the maximum number of ligands that can be attached to the metal; and m+n is the maximum number of ligands that can be attached to the metal.

In one aspect, (Y ¹ -Y ² ) is a 2-phenylpyridine derivative.

In another aspect, (Y ¹ -Y ² ) is a carbene ligand.

In another aspect, M is selected from the group consisting of Ir, Pt, Os, and Zn.

In another aspect, the metal complex has a solution state minimum oxidation potential of less than about 0.6 V relative to the Fc ⁺ /Fc pair.

Main material:

The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as a light-emitting material, and a host material as disclosed herein. Other host materials are possible, and examples are not particularly limited. Any metal complex or organic compound can be used as long as the bulk triplet energy is greater than the triplet energy of the dopant.

The example of the metal complex used as the host preferably has the following formula:

Wherein M' is a metal; (Y ³ -Y ⁴ ) is a bidentate ligand, Y ³ and Y ^{4 are} independently selected from C, N, O, P and S; L is an auxiliary ligand; m is 1 An integer value up to the maximum number of ligands that can be attached to the metal; and m+n is the maximum number of ligands that can be attached to the metal.

In one aspect, the metal complex is:

(O-N) is a bidentate ligand having a metal coordinated to the O and N atoms.

In another aspect, M is selected from the group consisting of Ir and Pt.

In another aspect, (Y ³ -Y ⁴ ) is a carbene ligand.

Examples of the organic compound used as the host are selected from the group consisting of aromatic hydrocarbon ring compounds such as benzene, biphenyl, terphenyl, terphenyl, naphthalene, anthracene, anthracene, phenanthrene, anthracene, anthracene, , hydrazine, hydrazine; a group consisting of aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzo Selenium, carbazole, indolocarbazole, pyridylpurine, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, triazole, dioxazole, thiadiazole , pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxazine, oxadiazine, hydrazine, benzimidazole, carbazole, anthraquinone, benzoxazole, benzoisoxine Oxazole, benzothiazole, quinoline, isoquinoline, Porphyrin, quinazoline, quinololine, naphthyridine, pyridazine, acridine, dibenzopyran, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furobipyridine, Benzothienopyridine, thienobipyridine, benzoselenopyridine and selenophenodipyridine; and a group consisting of 2 to 10 cyclic structural units selected from aromatic hydrocarbon ring groups And the same type or different types of groups of the aromatic heterocyclic group, and directly or via at least one of an oxygen atom, a nitrogen atom, a sulfur atom, a ruthenium atom, a phosphorus atom, a boron atom, a chain structural unit, and an aliphatic cyclic group They are linked to each other. Wherein each group is further substituted with a substituent selected from the group consisting of hydrogen, alkyl, alkoxy, amine, alkenyl, alkynyl, aralkyl, heteroalkyl, aryl and heteroaryl .

In one aspect, the host compound contains at least one of the following groups in the molecule:

R ¹ to R ^{7 are} independently selected from the group consisting of hydrogen, alkyl, alkoxy, amine, alkenyl, alkynyl, aralkyl, heteroalkyl, aryl and heteroaryl, when In the case of an aryl or heteroaryl group, it has a definition similar to that of the above Ar.

k is an integer from 0 to 20.

X ¹ to X ^{8 are} selected from CH or N.

Hole blocking material:

A hole blocking layer (HBL) can be used to reduce the number of holes and/or excitons exiting the emissive layer. The presence of such barrier layers in the device can result in substantially higher efficiencies than similar devices lacking a barrier layer. Additionally, a barrier layer can be used to limit emission to a desired region of the OLED.

In one aspect, the compound used in the HBL contains the same molecule used as the host.

In another aspect, the compound used in the HBL contains at least one of the following groups in the molecule:

k is an integer up to 20; L is an auxiliary ligand, and m is an integer from 1 to 3.

Electronic transmission materials:

An electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer can be intrinsic (undoped) or doped. Doping can be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complex or organic compound may be used as long as it is typically used to transport electrons.

In one aspect, the compound used in the ETL contains at least one of the following groups in the molecule:

R ¹ is selected from the group consisting of hydrogen, alkyl, alkoxy, amine, alkenyl, alkynyl, aralkyl, heteroalkyl, aryl and heteroaryl, when it is aryl or hetero In the case of an aryl group, it has a definition similar to that of the above Ar.

Ar ¹ to Ar ³ have similar definitions to those described above.

k is an integer from 0 to 20.

X ¹ to X ⁸ are selected from CH or N.

In another aspect, the metal complex used in the ETL contains, but is not limited to, the following formula:

(ON) or (NN) is a bidentate ligand having a metal coordinated to the atom O, N or N, N; L is an auxiliary ligand; m is the largest coordination from 1 to a metal bondable The integer value of the number of bodies.

In addition to the materials disclosed herein and/or in combination with the materials disclosed herein, many hole injection materials, hole transport materials, host materials, dopant materials, exciton/hole barrier materials can also be used in the OLED. , electron transport materials and electron injecting materials. Non-limiting examples of materials that can be used in OLEDs in combination with the materials disclosed herein are listed in Table 1 below. Table 1 lists non-limiting categories of materials, non-limiting examples of compounds of each class, and references that disclose such materials.

experiment Evaporation example

Here, the miscellaneous organometallic phosphorescent material (i.e., the first compound) and H1 or H2 (i.e., the second compound) exhibit high consistency premix evaporation. Evaporation results were analyzed by high performance liquid chromatography (HPLC) of premixed evaporation membranes and OLED efficacy and lifetime of devices with premixed evaporation materials in the EML.

Example 1.

H1 and D1 having the chemical structures shown above exhibit stable premixability, which means that they can be premixed and co-deposited from one source without changing the composition. Uniform co-evaporation of the two materials is critical to the consistency of the performance of the device from which the mixture is made.

The premixability of these two compounds was tested by HPLC analysis of the evaporated film. For this purpose, 0.39 g of H1 and 0.11 g of D1 were mixed and ground. 0.5 g of the mixture was charged into the evaporation source of the vacuum VTE chamber. The chamber is aspirated to a pressure of 10 ^-7 Torr. The premixed components were deposited onto the glass substrate at a rate of 2 Å/s. The substrate was continuously replaced after depositing a 400 Å film without stopping the deposition and cooling sources.

The membrane was analyzed by HPLC and the results are shown in Table 2. The composition of components H1 and D1 did not change significantly from plate 1 to plate 10. Some concentration fluctuations do not exhibit any trend and can be explained by the accuracy of HPLC analysis. Typically, concentration changes before and after deposition within 5% throughout the process are considered good and are suitable for commercial OLED applications.

This is evidence that H1 and D1 form a stable co-evaporation mixture.

HPLC conditions C18, 80-100 40 minutes, detection wavelength 254nm

Example 2.

H2 and D1 (chemical structures shown above) show another example of stable premixability between these two material families, which means that they can be premixed and co-deposited from one source without changing composition.

The premixability of these two compounds was tested by HPLC analysis of the evaporated film. For this purpose, 0.84 g of H2 and 0.16 g of D1 were mixed and ground. One gram of the mixture was charged to the evaporation source of the vacuum VTE chamber. The chamber is aspirated to a pressure of 10 ^-7 Torr. The premixed components were deposited onto the glass substrate at a rate of 2 Å/s. The substrate was continuously replaced after depositing a 400 Å film without stopping the deposition and cooling sources.

The membrane was analyzed by HPLC and the results are shown in Table 3. The composition of components H2 and D1 did not change significantly from plate 1 to plate 4. Some concentration fluctuations do not exhibit any trend and can be explained by the accuracy of HPLC analysis. Typically, concentration changes before and after deposition within 5% throughout the process are considered good and are suitable for commercial OLED applications.

Table 3. HPLC composition (%) of the film deposited from the premixed dopant/host material combination H2:D1 sequentially:

HPLC conditions C18, 80-100 40 minutes, detection wavelength 254nm

It is understood that the various embodiments described herein are by way of example only and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein may be substituted with other materials and structures without departing from the spirit of the invention. The invention as claimed may thus include variations of the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It should be understood that the various theories as to why the invention works are not intended to be limiting.

100‧‧‧Organic lighting device

110‧‧‧Substrate

115‧‧‧Anode

120‧‧‧ hole injection layer

125‧‧‧ hole transport layer

130‧‧‧Electronic barrier

135‧‧‧ emission layer

140‧‧‧ hole barrier

145‧‧‧Electronic transport layer

150‧‧‧electron injection layer

155‧‧‧Protective layer

160‧‧‧ cathode

162‧‧‧First conductive layer

164‧‧‧Second conductive layer

Claims (16)

An organic light-emitting device comprising an anode layer, a cathode layer, and an emission layer between the anode layer and the cathode layer; wherein the emission layer comprises a material combination, wherein the material combination comprises an evaporated premix material, the premix The material comprises a physical mixture of: a first compound, wherein the first compound is an organometallic phosphorescent dopant compound having the formula L ₂ MX, LL'MX, LL'L"M or LMXX', wherein L, L ', L", X and X' are unequal bidentate ligands, and M is a metal having an atomic weight greater than 40, wherein L, L' and L" are coordinated to carbon by sp ² mixed carbon to M An anion non-equivalent bidentate ligand, wherein the organometallic phosphorescent dopant compound is selected from the group consisting of an organometallic platinum compound, an organometallic ruthenium compound, and an organometallic ruthenium compound, and wherein the organometallic platinum compound, ruthenium compound, and The ruthenium compound optionally includes an aromatic ligand, and the second compound, wherein the second compound is an organoheteroaromatic host compound having the formula (1): Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings, and t represents an integer of 1 to 3 So that when t is greater than 2, each Z may be the same or different Z is represented by the formula (1a): Wherein ring A is an aromatic hydrocarbon ring represented by formula (1b): Ring B is a heterocyclic ring represented by the formula (1c): Rings A and B are each condensed with an adjacent ring; each R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic group of 3 to 17 carbon atoms. a heterocyclic group, in the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring; m represents 0 or an integer of 1 to 2, n represents 0 or an integer 1, and X ¹ is O or S or N-Ar ¹ or N, wherein Ar ¹ is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings, X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings. The device of claim 1, further comprising a third compound, wherein the third compound is an organometallic phosphorescent dopant different from the first compound, and wherein the first compound, the second compound, and the third compound The relationship between the triplet energy levels is: The third compound <the first compound <the second compound. The device of claim 1, further comprising a third compound, wherein the third compound is an organometallic phosphorescent dopant different from the first compound, and wherein the first compound, the second compound, and the third compound The relationship between the triplet energy levels is: the first compound <the third compound < the second compound. The device of any one of claims 1 to 3, wherein the first compound is: Wherein M is Ir, Pt or Os each R 'is independently selected from the group consisting of: H, alkyl, alkenyl, alkynyl, _{alkylaryl, CN, CF 3, C n} F 2n + 1, trifluoroethylene a group, CO ₂ R", C(O)R", NR" ₂ , NO ₂ , OR", halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl or heterocyclic, and Wherein each R" is independently H, alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or aralkyl; each of Ar', Ar", Ar''' and Ar'''' Independently represents a substituted or unsubstituted aryl or heteroaryl non-fused substituent on a phenylpyridine ligand; a is 0 or 1; b is 0 or 1; c is 0 or 1; 0 or 1; m' is 1 or 2; n' is 1 or 2; m'+n' is the maximum number of ligands which can be coordinated to M; and wherein at least one of a, b, c and d Is 1 and when at least one of a and b is 1 and at least one of b and c is 1, at least one of Ar' and Ar" is different from Ar''' and Ar''' At least one of the 'and the second compound is an organoheteroaromatic host compound having the formula (2): Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings, and t represents an integer of 1 to 3 So that when t is greater than 2, each Z may be the same or different Z is represented by the formula (2a): Wherein ring A is an aromatic hydrocarbon ring represented by formula (2b): Ring B is a heterocyclic ring represented by the formula (2c): Rings A and B are each condensed with an adjacent ring; each R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic group of 3 to 17 carbon atoms. a heterocyclic group, in the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring; m represents 0 or an integer of 1 to 2, n represents 0 or an integer 1, and X ² is O or S or N-Ar ² , wherein Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or an aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings. The apparatus of any one of claims 1 to 3, wherein the second compound is an organoheteroaromatic host compound having the formula (3): Wherein Y is a t-valent aromatic hydrocarbon group of 6 to 50 carbon atoms or a t-valent aromatic heterocyclic group of 3 to 50 carbon atoms excluding a group having more than 5 condensed rings, and t represents an integer of 1 to 3 So that when t is greater than 2, each Z may be the same or different Z is represented by the formula (3a): Wherein ring A is an aromatic hydrocarbon ring represented by formula (3b): Ring B is a heterocyclic ring represented by the formula (3c): Rings A and B are each condensed with an adjacent ring; each R is independently selected from hydrogen, an aliphatic hydrocarbon group of 1 to 10 carbon atoms, an aromatic hydrocarbon group of 6 to 18 carbon atoms or an aromatic group of 3 to 17 carbon atoms. a heterocyclic group, in the case where R is an aromatic hydrocarbon group or an aromatic heterocyclic group, R may be condensed with a benzene ring, Ar ² is an aromatic hydrocarbon group of 6 to 50 carbon atoms or excluded from having more than 5 condensed rings An aromatic heterocyclic group of 3 to 50 carbon atoms of the group. The organic light-emitting device of any one of claims 1 to 3, wherein each of Ar and Y comprises a group selected from the group consisting of benzene, naphthalene, anthracene, pyridine, pyrazine, pyrimidine, pyridazine, Triazine, isoindole, carbazole, anthracene, isoquinoline, imidazole, Pyridine, pyridazine, quinazoline, quinoxaline, Porphyrin, quinoline, acridine, phenanthridine, acridine, acridine, phenanthroline, phenazine, porphyrin, hydrazine, benzoxazole, benzothiazole, carbazole, dibenzofuran, dibenzothiophene And an aromatic compound in which a plurality of such groups are bonded together. The organic light-emitting device of claim 1, wherein the evaporation temperature of the first compound is within 30 ° C of the evaporation temperature of the second compound. The organic light-emitting device of claim 2 or 3, wherein an evaporation temperature of at least one of the first compound, the second compound, and the third compound is in the first compound, the second compound, and the third compound The evaporation temperature of at least one of the others is within 30 °C. The organic light-emitting device of claim 2 or 3, wherein an evaporation temperature of at least one of the first compound, the second compound, and the third compound is in the first compound, the second compound, and the third compound The evaporation temperature of at least one of the others is within 10 °C. The organic light-emitting device of claim 2 or 3, wherein each of the first compound, the second compound, and the third compound has an evaporation temperature of 30 ° C of each other. The organic light-emitting device of claim 2 or 3, wherein the evaporation temperature of the first compound is within 30 ° C of the evaporation temperature of the third compound. The organic light-emitting device of claim 2 or 3, wherein the evaporation temperature of the second compound is within 30 ° C of the evaporation temperature of the third compound. The organic light-emitting device of claim 2 or 3, wherein the evaporation temperature of the first compound is within 30 ° C of the evaporation temperature of the second compound. The organic light-emitting device of claim 2 or 3, wherein the pre-mixed material further comprises the third compound. A composition comprising an evaporated premixed material comprising a physical mixture of a first compound and a second compound, wherein the first compound comprises the first compound of claim 1 and the second compound comprises A second compound as claimed in claim 1. A composition comprising a premixed material comprising a physical mixture of a first compound and a second compound, wherein the first compound comprises the first compound of claim 1 and the second compound comprises The second compound.